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Poku R, Amissah F, Alan JK. PI3K Functions Downstream of Cdc42 to Drive Cancer phenotypes in a Melanoma Cell Line. Small GTPases 2023; 14:1-13. [PMID: 37114375 PMCID: PMC10150613 DOI: 10.1080/21541248.2023.2202612] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
Rho proteins are part of the Ras superfamily, which function to modulate cytoskeletal dynamics including cell adhesion and motility. Recently, an activating mutation in Cdc42, a Rho family GTPase, was found in a patient sample of melanoma. Previously, our work had shown the PI3K was important downstream of mutationally active Cdc42. Our present study sought to determine whether PI3K was a crucial downstream partner for Cdc42 in a melanoma cells line with a BRAF mutation, which is the most common mutation in cutaneous melanoma. In this work we were able to show that Cdc42 contributes to proliferation, anchorage-independent growth, cell motility and invasion. Treatment with a pan-PI3K inhibitor was able to effectively ameliorate all these cancer phenotypes. These data suggest that PI3K may be an important target downstream of Cdc42 in melanoma.
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Affiliation(s)
- Rosemary Poku
- College of Medicine, Central Michigan University, Mt. Pleasant, MI, USA
| | - Felix Amissah
- Department of Pharmaceutical Science, Ferris State University, Big Rapids, MI, USA
| | - Jamie K Alan
- Department of Pharmacology and Toxicology, College of Human Medicine, Michigan State University, East Lansing, MI, USA
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2
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Noviello C, Kobon K, Randrianarison-Huetz V, Maire P, Pietri-Rouxel F, Falcone S, Sotiropoulos A. RhoA Is a Crucial Regulator of Myoblast Fusion. Cells 2023; 12:2673. [PMID: 38067102 PMCID: PMC10705320 DOI: 10.3390/cells12232673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 12/18/2023] Open
Abstract
Satellite cells (SCs) are adult muscle stem cells that are mobilized when muscle homeostasis is perturbed. Here we show that RhoA in SCs is indispensable to have correct muscle regeneration and hypertrophy. In particular, the absence of RhoA in SCs prevents a correct SC fusion both to other RhoA-deleted SCs (regeneration context) and to growing control myofibers (hypertrophy context). We demonstrated that RhoA is dispensable for SCs proliferation and differentiation; however, RhoA-deleted SCs have an inefficient movement even if their cytoskeleton assembly is not altered. Proliferative myoblast and differentiated myotubes without RhoA display a decreased expression of Chordin, suggesting a crosstalk between these genes for myoblast fusion regulation. These findings demonstrate the importance of RhoA in SC fusion regulation and its requirement to achieve an efficient skeletal muscle homeostasis restoration.
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Affiliation(s)
- Chiara Noviello
- Institut Cochin, Université de Paris, INSERM U1016, CNRS, F-75014 Paris, France (P.M.); (A.S.)
- Centre de Recherche en Myologie, Sorbonne Université, INSERM UMRS 974, Institut de Myologie, F-75013 Paris, France;
| | - Kassandra Kobon
- Institut Cochin, Université de Paris, INSERM U1016, CNRS, F-75014 Paris, France (P.M.); (A.S.)
| | | | - Pascal Maire
- Institut Cochin, Université de Paris, INSERM U1016, CNRS, F-75014 Paris, France (P.M.); (A.S.)
| | - France Pietri-Rouxel
- Centre de Recherche en Myologie, Sorbonne Université, INSERM UMRS 974, Institut de Myologie, F-75013 Paris, France;
| | - Sestina Falcone
- Centre de Recherche en Myologie, Sorbonne Université, INSERM UMRS 974, Institut de Myologie, F-75013 Paris, France;
| | - Athanassia Sotiropoulos
- Institut Cochin, Université de Paris, INSERM U1016, CNRS, F-75014 Paris, France (P.M.); (A.S.)
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TNS1: Emerging Insights into Its Domain Function, Biological Roles, and Tumors. BIOLOGY 2022; 11:biology11111571. [PMID: 36358270 PMCID: PMC9687257 DOI: 10.3390/biology11111571] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/24/2022] [Accepted: 10/25/2022] [Indexed: 01/25/2023]
Abstract
Tensins are a family of cellular-adhesion constituents that have been extensively studied. They have instrumental roles in the pathogenesis of numerous diseases. The mammalian tensin family comprises four members: tensin1 (TNS1), tensin2, tensin3, and tensin4. Among them, TNS1 has recently received attention from researchers because of its structural properties. TNS1 engages in various biological processes, such as cell adhesion, polarization, migration, invasion, proliferation, apoptosis, and mechano-transduction, by interacting with various partner proteins. Moreover, the abnormal expression of TNS1 in vivo is associated with the development of various diseases, especially tumors. Interestingly, the role of TNS1 in different tumors is still controversial. Here, we systematically summarize three aspects of TNS1: the gene structure, the biological processes underlying its action, and the dual regulatory role of TNS1 in different tumors through different mechanisms, of which we provide the first overview.
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4
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Fixing the GAP: the role of RhoGAPs in cancer. Eur J Cell Biol 2022; 101:151209. [DOI: 10.1016/j.ejcb.2022.151209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/29/2022] [Accepted: 02/08/2022] [Indexed: 12/12/2022] Open
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Kazmi N, Robinson T, Zheng J, Kar S, Martin RM, Ridley AJ. Rho GTPase gene expression and breast cancer risk: a Mendelian randomization analysis. Sci Rep 2022; 12:1463. [PMID: 35087170 PMCID: PMC8795400 DOI: 10.1038/s41598-022-05549-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 01/12/2022] [Indexed: 01/07/2023] Open
Abstract
The Rho GTPase family consists of 20 genes encoding intracellular signalling proteins that influence cytoskeletal dynamics, cell migration and cell cycle progression. They are implicated in breast cancer progression but their role in breast cancer aetiology is unknown. As aberrant Rho GTPase activity could be associated with breast cancer, we aimed to determine the potential for a causal role of Rho GTPase gene expression in breast cancer risk, using two-sample Mendelian randomization (MR). MR was undertaken in 122,977 breast cancer cases and 105,974 controls, including 69,501 estrogen receptor positive (ER+) cases and 105,974 controls, and 21,468 ER negative (ER-) cases and 105,974 controls. Single nucleotide polymorphisms (SNPs) underlying expression quantitative trait loci (eQTLs) obtained from normal breast tissue, breast cancer tissue and blood were used as genetic instruments for Rho GTPase expression. As a sensitivity analysis, we undertook co-localisation to examine whether findings reflected shared causal variants or genomic confounding. We identified genetic instruments for 14 of the 20 human Rho GTPases. Using eQTLs obtained from normal breast tissue and normal blood, we identified evidence of a causal role of RHOD in overall and ER+ breast cancers (overall breast cancer: odds ratio (OR) per standard deviation (SD) increase in expression level 1.06; (95% confidence interval (CI) 1.03, 1.09; P = 5.65 × 10-5) and OR 1.22 (95% CI 1.11, 1.35; P = 5.22 × 10-5) in normal breast tissue and blood respectively). There was a consistent direction of association for ER- breast cancer, although the effect-estimate was imprecisely estimated. Using eQTLs from breast cancer tissue and normal blood there was some evidence that CDC42 was negatively associated with overall and ER + breast cancer risk. The evidence from colocalization analyses strongly supported our MR results particularly for RHOD. Our study suggests a potential causal role of increased RHOD gene expression, and, although the evidence is weaker, a potential protective role for CDC42 gene expression, in overall and ER+ breast cancers. These finding warrant validation in independent samples and further biological investigation to assess whether they may be suitable targets for drug targeting.
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Affiliation(s)
- Nabila Kazmi
- MRC Integrative Epidemiology Unit (IEU), Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK.
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK.
| | - Tim Robinson
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK.
| | - Jie Zheng
- MRC Integrative Epidemiology Unit (IEU), Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK
| | - Siddhartha Kar
- MRC Integrative Epidemiology Unit (IEU), Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK
| | - Richard M Martin
- MRC Integrative Epidemiology Unit (IEU), Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, BS8 2BN, UK
- National Institute for Health Research (NIHR) Bristol Biomedical Research Centre, University Hospitals NHS Trust and University of Bristol, Bristol, UK
| | - Anne J Ridley
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
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Afshari AR, Mollazadeh H, Henney NC, Jamialahmad T, Sahebkar A. Effects of statins on brain tumors: a review. Semin Cancer Biol 2021; 73:116-133. [DOI: 10.1016/j.semcancer.2020.08.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/04/2020] [Accepted: 08/09/2020] [Indexed: 02/06/2023]
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Comparison of Transcriptomic Profiles of MiaPaCa-2 Pancreatic Cancer Cells Treated with Different Statins. Molecules 2021; 26:molecules26123528. [PMID: 34207840 PMCID: PMC8226792 DOI: 10.3390/molecules26123528] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/21/2021] [Accepted: 05/26/2021] [Indexed: 01/24/2023] Open
Abstract
Statins have been widely used for the treatment of hypercholesterolemia due to their ability to inhibit HMG-CoA reductase, the rate-limiting enzyme of de novo cholesterol synthesis, via the so-called mevalonate pathway. However, their inhibitory action also causes depletion of downstream intermediates of the pathway, resulting in the pleiotropic effects of statins, including the beneficial impact in the treatment of cancer. In our study, we compared the effect of all eight existing statins on the expression of genes, the products of which are implicated in cancer inhibition and suggested the molecular mechanisms of their action in epigenetic and posttranslational regulation, and in cell-cycle arrest, death, migration, or invasion of the cancer cells.
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8
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Chen S, Duan H, Xie Y, Li X, Zhao Y. Expression and prognostic analysis of Rho GTPase-activating protein 11A in lung adenocarcinoma. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:872. [PMID: 34164506 PMCID: PMC8184474 DOI: 10.21037/atm-21-2113] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Background Rho GTPase-activating protein 11A (ARHGAP11A) is a member of the Rho GTPase-activating protein (RhoGAP) subfamily. However, its expression, prognostic significance and clinicopathologic factors correlation in lung adenocarcinoma is still unclear. Methods The original gene expression profile, survival data, and clinical information of patients with lung adenocarcinoma (LUAD) were downloaded from The Cancer Genome Atlas (TCGA) database. The expression difference of ARHGAP11A between LUAD tissues and adjacent normal tissues in the TCGA database was analyzed by using R software, and verified by the Oncomine database and immunohistochemical (IHC) assay of LUAD sections. Logistic regression was applied to analyze the relationship between the expression of ARHGAP11A and clinicopathological factors of LUAD. Kaplan-Meier (KM) survival curves and a Cox proportional-hazards model were selected to evaluate the prognostic significance of ARHGAP11A expression. Gene set enrichment analysis (GSEA) software was applied to screen the tumor signaling pathways associated with the low and high expression group of ARHGAP11A in LUAD. Results The TCGA database showed that the expression of ARHGAP11A was significantly higher in LUAD tissues than in normal tissues (P<0.001). The up-regulation of ARHGAP11A in LUAD was verified by the Oncomine database (P<0.001) and IHC assay (P<0.001). Logistic regression analysis revealed the high expression of ARHGAP11A to be closely related to age, sex, advanced pathological stage, advanced T stage, and lymph node metastasis. The KM plots based on the TCGA and KM plotter databases indicated that patients with LUAD highly expressing ARHGAP11A had a poorer overall survival (OS) than patients with low expression of ARHGAP11A. Multivariate Cox regression analysis showed that the high expression of ARHGAP11A could be an important independent predictor of a poor prognosis of LUAD [hazards ratio (HR) =1.385; P<0.001]. GSEA indicated that 10 signal pathways were significantly enriched in LUAD samples with the ARHGAP11A expression phenotype. Conclusions ARHGAP11A may play a carcinogenic role in the malignant progression of LUAD, and it can be considered as a new independent prognostic factor and potential therapeutic target for LUAD.
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Affiliation(s)
- Shuchen Chen
- Department of Radiation Oncology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.,Department of Thoracic Cancer 1, Cancer Hospital of China Medical University, Liaoning Cancer Hospital and Institute, Shenyang, China
| | - He Duan
- Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
| | - Yusai Xie
- Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Xiaoling Li
- Department of Thoracic Cancer 1, Cancer Hospital of China Medical University, Liaoning Cancer Hospital and Institute, Shenyang, China
| | - Yuxia Zhao
- Department of Radiation Oncology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
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9
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Gjelaj E, Hamel PA. Distinct epithelial-to-mesenchymal transitions induced by PIK3CA H1047R and PIK3CB. J Cell Sci 2021; 134:jcs.248294. [PMID: 33526718 DOI: 10.1242/jcs.248294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 01/13/2021] [Indexed: 02/01/2023] Open
Abstract
The most common PIK3CA mutation, producing the H1047R mutant of p110α, arises in myriad malignancies and is typically observed in low-grade breast tumours. In contrast, amplification is observed for wild-type PIK3CB, encoding p110β, and occurs at low frequency but in aggressive, high-grade metastatic tumours. We hypothesized that mutant p110αH1047R and wild-type p110β give rise to distinct transformed phenotypes. We show that p110αH1047R and wild-type p110β, but not wild-type p110α, transform MCF-10A cells and constitutively stimulate phosphoinositide 3-kinase (PI3K)-AKT pathway signalling. However, their resultant morphological transformed phenotypes are distinct. p110αH1047R induced an epithelial-to-mesenchymal transition (EMT) commensurate with SNAIL (also known as SNAI1) induction and loss of E-cadherin. Upon p110β expression, however, E-cadherin expression was maintained despite cells readily delaminating from epithelial sheets. Distinct from the prominent filopodia in p110αH1047R-expressing cells, p110β induced formation of lamellipodia, and these cells migrated with significantly greater velocity and decreased directionality. p110β-induced phenotypic alterations were accompanied by hyperactivation of RAC1; the dependency of transformation of p110β-binding to Rac1 revealed using a Rac1-binding mutant of p110β. Thus, PIK3CB amplification induces a transformed phenotype that is dependent upon a p110β-Rac1 signalling loop and is distinct from the transformed phenotype induced by p110αH1047R.
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Affiliation(s)
- Ersa Gjelaj
- Department of Laboratory Medicine & Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Paul A Hamel
- Department of Laboratory Medicine & Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
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10
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Abdrabou A, Wang Z. Regulation of the nuclear speckle localization and function of Rac1. FASEB J 2021; 35:e21235. [PMID: 33417283 DOI: 10.1096/fj.202001694r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 11/02/2020] [Accepted: 11/16/2020] [Indexed: 11/11/2022]
Abstract
Despite significant evidence that Rac1 is localized to the nucleus, little is known regarding the function and biological significance of nuclear Rac1. Here, we showed that in response to EGF Rac1 was translocated to nuclear speckles and co-localized with the nuclear speckle marker Serine/arginine-rich splicing factor 2 (SRSF2) in Cos-7 cells. We also showed that the nuclear speckle localization of Rac1 was dependent on its T108 phosphorylation and facilitated by Rac1 polybasic region (PBR) that contains a nuclear localization signal and Rac1 GTPase activity. To gain insight into the function of Rac1 in nuclear speckles, we searched for Rac1 binding proteins in the nucleus. We isolated nuclear fraction of HEK 293 cells and incubated with GST-Rac1 and the phosphomimetic GST-Rac1T108E. We identified 463 proteins that were associated with GST-Rac1T108E, but not with GST-Rac1 by LC-MS/MS. Three notable groups of these proteins are: the heterogeneous nuclear ribonucleoproteins (hnRNPs), small nuclear ribonucleoproteins (snRNPs), and SRSFs, all of which are involved in pre-mRNA splicing and associated with nuclear speckles. We further showed by co-immunoprecipitation that Rac1 interacts with SRSF2, hnRNPA1, and U2A' in response to EGF. The interaction is dependent on T108 phosphorylation and facilitated by Rac1 PBR and GTPase activity. We showed that hnRNPA1 translocated in and out of nucleus in response to EGF in a similar pattern to Rac1. Rac1 only partially colocalized with U2A' that localizes to the actual splicing sites adjacent to nuclear speckle. Finally, we showed that Rac1 regulated EGF-induced pre-mRNA splicing and this is mediated by T108 phosphorylation. We conclude that in response to EGF, T108 phosphorylated Rac1 is targeted to nuclear speckles, interacts with multiple groups of proteins involved in pre-mRNA splicing, and regulates EGF-induced pre-mRNA splicing.
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Affiliation(s)
- Abdalla Abdrabou
- Department of Medical Genetics and Signal, Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Zhixiang Wang
- Department of Medical Genetics and Signal, Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
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Abdelmonsef AH, Mosallam AM. Synthesis, in vitro biological evaluation and in silico docking studies of new quinazolin‐2,4‐dione analogues as possible anticarcinoma agents. J Heterocycl Chem 2020. [DOI: 10.1002/jhet.3889] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
| | - Ahmed M. Mosallam
- Chemistry Department, Faculty of ScienceSouth Valley University Qena Egypt
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12
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Wang L, Shi J, Huang Y, Liu S, Zhang J, Ding H, Yang J, Chen Z. A six-gene prognostic model predicts overall survival in bladder cancer patients. Cancer Cell Int 2019; 19:229. [PMID: 31516386 PMCID: PMC6729005 DOI: 10.1186/s12935-019-0950-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/27/2019] [Indexed: 01/02/2023] Open
Abstract
Background The fatality and recurrence rates of bladder cancer (BC) have progressively increased. DNA methylation is an influential regulator associated with gene transcription in the pathogenesis of BC. We describe a comprehensive epigenetic study performed to analyse DNA methylation-driven genes in BC. Methods Data related to DNA methylation, the gene transcriptome and survival in BC were downloaded from The Cancer Genome Atlas (TCGA). MethylMix was used to detect BC-specific hyper-/hypo-methylated genes. Metascape was used to carry out gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. A least absolute shrinkage and selection operator (LASSO)-penalized Cox regression was conducted to identify the characteristic dimension decrease and distinguish prognosis-related methylation-driven genes. Subsequently, we developed a six-gene risk evaluation model and a novel prognosis-related nomogram to predict overall survival (OS). A survival analysis was carried out to explore the individual prognostic significance of the six genes. Results In total, 167 methylation-driven genes were identified. Based on the LASSO Cox regression, six genes, i.e., ARHGDIB, LINC00526, IDH2, ARL14, GSTM2, and LURAP1, were selected for the development of a risk evaluation model. The Kaplan–Meier curve indicated that patients in the low-risk group had considerably better OS (P = 1.679e−05). The area under the curve (AUC) of this model was 0.698 at 3 years of OS. The verification performed in subgroups demonstrated the validity of the model. Then, we designed an OS-associated nomogram that included the risk score and clinical factors. The concordance index of the nomogram was 0.694. The methylation levels of IDH2 and ARL14 were appreciably related to the survival results. In addition, the methylation and gene expression-matched survival analysis revealed that ARHGDIB and ARL14 could be used as independent prognostic indicators. Among the six genes, 6 methylation sites in ARHGDIB, 3 in GSTM2, 1 in ARL14, 2 in LINC00526 and 2 in LURAP1 were meaningfully associated with BC prognosis. In addition, several abnormal methylated sites were identified as linked to gene expression. Conclusion We discovered differential methylation in BC patients with better and worse survival and provided a risk evaluation model by merging six gene markers with clinical characteristics.
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Affiliation(s)
- Liwei Wang
- 1Urology Institute of People's Liberation Army, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China.,Unit 32357 of People's Liberation Army, Pujiang, 611630 People's Republic of China
| | - Jiazhong Shi
- 3Department of Cell Biology, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
| | - Yaqin Huang
- 3Department of Cell Biology, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
| | - Sha Liu
- 3Department of Cell Biology, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
| | - Jingqi Zhang
- 1Urology Institute of People's Liberation Army, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
| | - Hua Ding
- 1Urology Institute of People's Liberation Army, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
| | - Jin Yang
- 3Department of Cell Biology, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
| | - Zhiwen Chen
- 1Urology Institute of People's Liberation Army, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 People's Republic of China
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Nacher-Soler G, Garrido JM, Rodríguez-Serrano F. Hearing regeneration and regenerative medicine: present and future approaches. Arch Med Sci 2019; 15:957-967. [PMID: 31360190 PMCID: PMC6657260 DOI: 10.5114/aoms.2019.86062] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 05/28/2017] [Indexed: 01/04/2023] Open
Abstract
More than 5% of the world population lives with a hearing impairment. The main factors responsible for hearing degeneration are ototoxic drugs, aging, continued exposure to excessive noise and infections. The pool of adult stem cells in the inner ear drops dramatically after birth, and therefore an endogenous cellular source for regeneration is absent. Hearing loss can emerge after the degeneration of different cochlear components, so there are multiple targets to be reached, such as hair cells (HCs), spiral ganglion neurons (SGNs), supporting cells (SCs) and ribbon synapses. Important discoveries in the hearing regeneration field have been reported regarding stem cell transplantation, migration and survival; genetic systems for cell fate monitoring; and stem cell differentiation to HCs, SGNs and SCs using adult stem cells, embryonic stem cells and induced pluripotent stem cells. Moreover, some molecular mediators that affect the establishment of functional synapses have been identified. In this review, we will focus on reporting the state of the art in the regenerative medicine field for hearing recovery. Stem cell research has enabled remarkable advances in regeneration, particularly in neuronal cells and synapses. Despite the progress achieved, there are certain issues that need a deeper development to improve the results already obtained, or to develop new approaches aiming for the clinical application.
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Affiliation(s)
- German Nacher-Soler
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada, Spain
| | - José Manuel Garrido
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada, Spain
- Department of Cardiovascular Surgery, Virgen de las Nieves University Hospital, Granada, Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA), Granada, Spain
| | - Fernando Rodríguez-Serrano
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada, Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA), Granada, Spain
- Department of Human Anatomy and Embryology, University of Granada, Granada, Spain
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Yeh SJ, Chang CA, Li CW, Wang LHC, Chen BS. Comparing progression molecular mechanisms between lung adenocarcinoma and lung squamous cell carcinoma based on genetic and epigenetic networks: big data mining and genome-wide systems identification. Oncotarget 2019; 10:3760-3806. [PMID: 31217907 PMCID: PMC6557199 DOI: 10.18632/oncotarget.26940] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 04/29/2019] [Indexed: 02/07/2023] Open
Abstract
Non-small-cell lung cancer (NSCLC) is the predominant type of lung cancer in the world. Lung adenocarcinoma (LADC) and lung squamous cell carcinoma (LSCC) are subtypes of NSCLC. We usually regard them as different disease due to their unique molecular characteristics, distinct cells of origin and dissimilar clinical response. However, the differences of genetic and epigenetic progression mechanism between LADC and LSCC are complicated to analyze. Therefore, we applied systems biology approaches and big databases mining to construct genetic and epigenetic networks (GENs) with next-generation sequencing data of LADC and LSCC. In order to obtain the real GENs, system identification and system order detection are conducted on gene regulatory networks (GRNs) and protein-protein interaction networks (PPINs) for each stage of LADC and LSCC. The core GENs were extracted via principal network projection (PNP). Based on the ranking of projection values, we got the core pathways in respect of KEGG pathway. Compared with the core pathways, we found significant differences between microenvironments, dysregulations of miRNAs, epigenetic modifications on certain signaling transduction proteins and target genes in each stage of LADC and LSCC. Finally, we proposed six genetic and epigenetic multiple-molecule drugs to target essential biomarkers in each progression stage of LADC and LSCC, respectively.
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Affiliation(s)
- Shan-Ju Yeh
- Laboratory of Automatic Control, Signaling Processing, and Systems Biology, Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Chien-An Chang
- Laboratory of Automatic Control, Signaling Processing, and Systems Biology, Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Cheng-Wei Li
- Laboratory of Automatic Control, Signaling Processing, and Systems Biology, Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Lily Hui-Ching Wang
- Department of Medical Science, Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Bor-Sen Chen
- Laboratory of Automatic Control, Signaling Processing, and Systems Biology, Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.,Department of Electrical Engineering, Yuan Ze University, Chungli 32003, Taiwan
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15
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Tan M, Asad M, Heong V, Wong MK, Tan TZ, Ye J, Kuay KT, Thiery JP, Scott C, Huang RYJ. The FZD7-TWIST1 axis is responsible for anoikis resistance and tumorigenesis in ovarian carcinoma. Mol Oncol 2019; 13:757-780. [PMID: 30548372 PMCID: PMC6441896 DOI: 10.1002/1878-0261.12425] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/24/2018] [Accepted: 11/20/2018] [Indexed: 12/20/2022] Open
Abstract
Frizzled family receptor 7 (FZD7), a Wnt signaling receptor, is associated with the maintenance of stem cell properties and cancer progression. FZD7 has emerged as a potential therapeutic target because it is capable of transducing both canonical and noncanonical Wnt signals. In this study, we investigated the regulatory pathway downstream of FZD7 and its functional roles. We found that FZD7 expression was crucial to the maintenance of the mesenchymal phenotype, anoikis resistance, and spheroid and tumor formation in ovarian cancer (OC). We identified TWIST1 as the crucial downstream effector of the FZD7 pathway. TWIST1, a basic helix loop helix transcription factor, is known to associate with mesenchymal and cancer stem cell phenotypes. Manipulating TWIST1 expression mimicked the functional consequences observed in the FZD7 model, and overexpression of TWIST1 partially rescued the functional phenotypes abolished by FZD7 knockdown. We further proved that FZD7 regulated TWIST1 expression through epigenetic modifications of H3K4me3 and H3K27ac at the TWIST1 proximal promoter. We also identified that the FZD7‐TWIST1 axis regulates the expression of BCL2, a gene that controls apoptosis. Identification of this FZD7‐TWIST1‐BCL2 pathway reaffirms the mechanism of anoikis resistance in OC. We subsequently showed that the FZD7‐TWIST1 axis can be targeted by using a small molecule inhibitor of porcupine, an enzyme essential for secretion and functional activation of Wnts. In conclusion, our results identified that the FZD7‐TWIST1 axis is important for tumorigenesis and anoikis resistance, and therapeutic inhibition results in cell death in OCs.
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Affiliation(s)
- Ming Tan
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore
| | - Mohammad Asad
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore.,Department of Obstetrics and Gynaecology, National University Hospital of Singapore, Singapore
| | - Valerie Heong
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore.,Department of Haematology-Oncology, National University Cancer Institute Singapore, Singapore.,Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Meng Kang Wong
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore
| | - Tuan Zea Tan
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore
| | - Jieru Ye
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore
| | - Kuee Theng Kuay
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore
| | - Jean Paul Thiery
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore.,Department of Biochemistry, National University of Singapore, Singapore.,Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Clare Scott
- Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Ruby Yun-Ju Huang
- Cancer Science Institute of Singapore, Singapore.,Center for Translational Medicine, National University of Singapore, Singapore.,Department of Obstetrics and Gynaecology, National University Hospital of Singapore, Singapore.,Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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16
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Dai B, Zhang X, Shang R, Wang J, Yang X, Zhang H, Liu Q, Wang D, Wang L, Dou K. Blockade of ARHGAP11A reverses malignant progress via inactivating Rac1B in hepatocellular carcinoma. Cell Commun Signal 2018; 16:99. [PMID: 30545369 PMCID: PMC6293628 DOI: 10.1186/s12964-018-0312-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 12/03/2018] [Indexed: 01/07/2023] Open
Abstract
Background The molecular signaling events involving in high malignancy and poor prognosis of hepatocellular carcinoma (HCC) are extremely complicated. Blockade of currently known targets has not yet led to successful clinical outcome. More understanding about the regulatory mechanisms in HCC is necessary for developing new effective therapeutic strategies for HCC patients. Methods The expression of Rho GTPase-activating protein 11A (ARHGAP11A) was examined in human normal liver and HCC tissues. The correlations between ARHGAP11A expression and clinicopathological stage or prognosis in HCC patients were analyzed. ARHGAP11A was downregulated to determine its role in the proliferation, invasion, migration, epithelial-to-mesenchymal transition (EMT) development, and regulatory signaling of HCC cells in vitro and in vivo. Results ARHGAP11A exhibited high expression in HCC, and was significantly correlated with clinicopathological stage and prognosis in HCC patients. Moreover, ARHGAP11A facilitated Hep3B and MHCC97-H cell proliferation, invasion, migration and EMT development in vitro. ARHGAP11A knockdown significantly inhibited the in vivo growth and metastasis of HCC cells. Furthermore, ARHGAP11A directly interacted with Rac1B independent of Rho GTPase- activating activity. Rac1B blockade effectively interrupted ARHGAP11A-elicited HCC malignant phenotype. Meanwhile, upregulation of Rac1B reversed ARHGAP11A knockdown mediated mesenchymal-to-epithelial transition (MET) development in HCC cells. Conclusion ARHGAP11A facilitates malignant progression in HCC patients via ARHGAP11A-Rac1B interaction. The ARHGAP11A/Rac1B signaling could be a potential therapeutic target in the clinical treatment of HCC. Electronic supplementary material The online version of this article (10.1186/s12964-018-0312-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bin Dai
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Xuan Zhang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Runze Shang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Jianlin Wang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Xisheng Yang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Hong Zhang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Qi Liu
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Desheng Wang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
| | - Lin Wang
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
| | - Kefeng Dou
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
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17
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Abdrabou A, Wang Z. Post-Translational Modification and Subcellular Distribution of Rac1: An Update. Cells 2018; 7:cells7120263. [PMID: 30544910 PMCID: PMC6316090 DOI: 10.3390/cells7120263] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 12/27/2022] Open
Abstract
Rac1 is a small GTPase that belongs to the Rho family. The Rho family of small GTPases is a subfamily of the Ras superfamily. The Rho family of GTPases mediate a plethora of cellular effects, including regulation of cytoarchitecture, cell size, cell adhesion, cell polarity, cell motility, proliferation, apoptosis/survival, and membrane trafficking. The cycling of Rac1 between the GTP (guanosine triphosphate)- and GDP (guanosine diphosphate)-bound states is essential for effective signal flow to elicit downstream biological functions. The cycle between inactive and active forms is controlled by three classes of regulatory proteins: Guanine nucleotide exchange factors (GEFs), GTPase-activating proteins (GAPs), and guanine-nucleotide-dissociation inhibitors (GDIs). Other modifications include RNA splicing and microRNAs; various post-translational modifications have also been shown to regulate the activity and function of Rac1. The reported post-translational modifications include lipidation, ubiquitination, phosphorylation, and adenylylation, which have all been shown to play important roles in the regulation of Rac1 and other Rho GTPases. Moreover, the Rac1 activity and function are regulated by its subcellular distribution and translocation. This review focused on the most recent progress in Rac1 research, especially in the area of post-translational modification and subcellular distribution and translocation.
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Affiliation(s)
- Abdalla Abdrabou
- Department of Medical Genetics, and Signal Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Zhixiang Wang
- Department of Medical Genetics, and Signal Transduction Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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18
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Kaushal N, Tiruchinapally G, Durmaz YY, Bao L, Gilani R, Merajver SD, ElSayed MEH. Synergistic inhibition of aggressive breast cancer cell migration and invasion by cytoplasmic delivery of anti-RhoC silencing RNA and presentation of EPPT1 peptide on "smart" particles. J Control Release 2018; 289:79-93. [PMID: 30149048 DOI: 10.1016/j.jconrel.2018.07.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 07/27/2018] [Indexed: 01/05/2023]
Abstract
Overexpression of RhoC protein in breast cancer patients has been linked to increased cancer cell invasion, migration, and metastases. Suppressing RhoC expression in aggressive breast cancer cells using silencing RNA (siRNA) molecules is a viable strategy to inhibit the metastatic spread of breast cancer. In this report, we describe the synthesis of a series of asymmetric pH-sensitive, membrane-destabilizing polymers engineered to complex anti-RhoC siRNA molecules forming "smart" nanoparticles. Using β-CD as the particle core, polyethylene glycol (PEG) chains were conjugated to the primary face via non-cleavable bonds and amphiphilic polymers incorporating hydrophobic and cationic monomers were grafted to the secondary face via acid-labile linkages. We investigated the effect of PEG molecular weight (2 & 5 kDa) on transfection capacity and serum stability of the formed particles. We evaluated the efficacy of EPPT1 peptides presented on the free tips of the PEG brush to function as a targeting ligand against underglycosylated MUC1 (uMUC1) receptors overexpressed on the surface of metastatic breast cancer cells. Results show that "smart" nanoparticles successfully delivered anti-RhoC siRNA into the cytoplasm of aggressive SUM149 and MDA-MB-231 breast cancer cells, which resulted in a dose-dependent inhibition of cell migration and invasion. Further, EPPT1-targeted nanoparticles demonstrate a synergistic inhibition of cell migration and invasion imparted via RhoC knockdown and EPPT1-mediated signaling via the uMUC1 receptor.
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Affiliation(s)
- Neha Kaushal
- University of Michigan, College of Engineering, Department of Biomedical Engineering, Cellular Engineering & Nano-Therapeutics Laboratory, Ann Arbor, MI 48109, USA
| | - Gopinath Tiruchinapally
- University of Michigan, College of Engineering, Department of Biomedical Engineering, Cellular Engineering & Nano-Therapeutics Laboratory, Ann Arbor, MI 48109, USA
| | - Yasemin Yuksel Durmaz
- Istanbul Medipol University, School of Engineering and Natural Sciences, Department of Biomedical Engineering, 34810 Istanbul, Turkey
| | - LiWei Bao
- University of Michigan, School of Medicine, Department of Internal Medicine, Ann Arbor, MI 48109, USA
| | - Rabia Gilani
- University of Michigan, School of Medicine, Department of Internal Medicine, Ann Arbor, MI 48109, USA
| | - Sofia D Merajver
- University of Michigan, School of Medicine, Department of Internal Medicine, Ann Arbor, MI 48109, USA
| | - Mohamed E H ElSayed
- University of Michigan, College of Engineering, Department of Biomedical Engineering, Cellular Engineering & Nano-Therapeutics Laboratory, Ann Arbor, MI 48109, USA; University of Michigan, Macromolecular Science and Engineering Program, 2300 Hayward Avenue, Ann Arbor, MI 48109, USA.
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19
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Alan JK, Robinson SK, Magsig KL, Demarco RS, Lundquist EA. The Atypical Rho GTPase CHW-1 Works with SAX-3/Robo To Mediate Axon Guidance in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2018; 8:1885-1895. [PMID: 29653940 PMCID: PMC5982818 DOI: 10.1534/g3.118.200148] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/26/2018] [Indexed: 01/12/2023]
Abstract
During development, neuronal cells extend an axon toward their target destination in response to a cue to form a properly functioning nervous system. Rho proteins, Ras-related small GTPases that regulate cytoskeletal organization and dynamics, cell adhesion, and motility, are known to regulate axon guidance. Despite extensive knowledge about canonical Rho proteins (RhoA/Rac1/Cdc42), little is known about the Caenorhabditis elegans (C. elegans) atypical Cdc42-like family members CHW-1 and CRP-1 in regards to axon pathfinding and neuronal migration. chw-1(Chp/Wrch) encodes a protein that resembles human Chp (Wrch-2/RhoV) and Wrch-1 (RhoU), and crp-1 encodes for a protein that resembles TC10 and TCL. Here, we show that chw-1 works redundantly with crp-1 and cdc-42 in axon guidance. Furthermore, proper levels of chw-1 expression and activity are required for proper axon guidance. When examining CHW-1 GTPase mutants, we found that the native CHW-1 protein is likely partially activated, and mutations at a conserved residue (position 12 using Ras numbering, position 18 in CHW-1) alter axon guidance and neural migration. Additionally, we showed that chw-1 genetically interacts with the guidance receptor sax-3 in PDE neurons. Finally, in VD/DD motor neurons, chw-1 works downstream of sax-3 to control axon guidance. In summary, this is the first study implicating the atypical Rho GTPases chw-1 and crp-1 in axon guidance. Furthermore, this is the first evidence of genetic interaction between chw-1 and the guidance receptor sax-3 These data suggest that chw-1 is likely acting downstream and/or in parallel to sax-3 in axon guidance.
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Affiliation(s)
- Jamie K Alan
- Department of Pharmacology and Toxicology; Michigan State University; East Lansing, MI 48824
| | - Sara K Robinson
- College of Medicine; Central Michigan University; Mount Pleasant, MI 48859
| | - Katie L Magsig
- College of Medicine; Central Michigan University; Mount Pleasant, MI 48859
| | - Rafael S Demarco
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS 60045
| | - Erik A Lundquist
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS 60045
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20
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Zhang L, Cao H, He T, Yang J, Tao H, Wang Y, Hu Q. Overexpression of PRDM13 inhibits glioma cells via Rho and GTP enzyme activation protein. Int J Mol Med 2018; 42:966-974. [PMID: 29767251 PMCID: PMC6034930 DOI: 10.3892/ijmm.2018.3679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 05/10/2018] [Indexed: 11/17/2022] Open
Abstract
PR (PRDI-BFI and RIZ) domain containing (PRDM) proteins have been shown to be important in several types of human cancer. PRDM13, a member of the PRDM family, contains transcriptional regulators involved in modulating several cellular processes. However, the function of PRDM13 in glioma remains to be elucidated. The purpose of the present study was to evaluate the expression and effect of PRDM13 on glioma cells. It was found that the expression of PRDM13 was reduced in glioma cells, and the overexpression of PRDM13 significantly decreased the proliferation, migration and invasion of U87 glioma cells. Through validation of RNA-sequencing analysis, genes regulating cell proliferation and migration were classified from Gene Ontology sources. In addition, PRDM13 was shown to be associated with Rho protein and GTP enzyme activation protein. The over expression of PRDM13 upregulated deleted in liver cancer 1 (DLC1) to inhibit the proliferation and invasion of U87 cells. In conclusion, PRDM13 decreased the proliferation and invasion of U87 cells, and may be of potential value for glioma therapy.
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Affiliation(s)
- Linna Zhang
- Department of Physiology, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Huimei Cao
- Department of Physiology, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Tao He
- Department of Spinal Surgery, Dongfeng General Hospital of Chinese Medicine Affiliated to Hubei Medical University, Shiyan, Hubei 442000, P.R. China
| | - Jijuan Yang
- Department of Physiology, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Hong Tao
- Department of Physiology, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Yin Wang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Basic Medical School of Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
| | - Qikuan Hu
- Department of Physiology, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
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21
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Vennin C, Murphy KJ, Morton JP, Cox TR, Pajic M, Timpson P. Reshaping the Tumor Stroma for Treatment of Pancreatic Cancer. Gastroenterology 2018; 154:820-838. [PMID: 29287624 DOI: 10.1053/j.gastro.2017.11.280] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 11/14/2017] [Accepted: 11/16/2017] [Indexed: 12/16/2022]
Abstract
Pancreatic cancer is accompanied by a fibrotic reaction that alters interactions between tumor cells and the stroma to promote tumor progression. Consequently, strategies to target the tumor stroma might be used to treat patients with pancreatic cancer. We review recently developed approaches for reshaping the pancreatic tumor stroma and discuss how these might improve patient outcomes. We also describe relationships between the pancreatic tumor extracellular matrix, the vasculature, the immune system, and metabolism, and discuss the implications for the development of stromal compartment-specific therapies.
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Affiliation(s)
- Claire Vennin
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Kendelle J Murphy
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Jennifer P Morton
- Cancer Research UK, The Beatson Institute for Cancer Research, Glasgow, Scotland, United Kingdom
| | - Thomas R Cox
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Marina Pajic
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.
| | - Paul Timpson
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.
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22
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MicroRNA-19a and microRNA-19b promote the malignancy of clear cell renal cell carcinoma through targeting the tumor suppressor RhoB. PLoS One 2018; 13:e0192790. [PMID: 29474434 PMCID: PMC5825063 DOI: 10.1371/journal.pone.0192790] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/30/2018] [Indexed: 01/02/2023] Open
Abstract
Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma, which shows high aggressiveness and lacks biomarkers. RhoB acts as a tumor suppressor that inhibits the progression of ccRCC. In the present study, we examined the effects of oncogenic microRNAs, miR-19a and miR-19b, on RhoB expression in ccRCC cells. The results showed that both miR-19a and miR-19b could directly target the 3′untranslated region (3’UTR) of RhoB, resulting in the reduced expression of RhoB. With RT-PCR analysis, we detected the increased expression of miR-19a and miR-19b in ccRCC tissues compared to adjacent non-tumor renal tissues. These data also demonstrated an exclusive negative correlation between miR-19a/19b and RhoB expression in ccRCC specimens and cell lines. In addition, the knockdown of RhoB or overexpression of miR-19a and miR-19b in ccRCC cells could promote cell proliferation, migration and invasion. These data demonstrate the direct roles of miR-19a and miR-19b on the repression of RhoB and its consequences on tumorigenesis, cancer cell proliferation and invasiveness. These results suggest the potential clinical impact of miR-19a and miR-19b as molecular targets for ccRCC.
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23
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Woldu SL, Hutchinson RC, Krabbe LM, Sanli O, Margulis V. The Rho GTPase signalling pathway in urothelial carcinoma. Nat Rev Urol 2017; 15:83-91. [PMID: 29133936 DOI: 10.1038/nrurol.2017.184] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Urothelial carcinoma remains a clinical challenge: non-muscle-invasive disease has a high rate of recurrence and risk of progression, and outcomes for patients with advanced disease are poor, owing to a lack of effective systemic therapies. The Rho GTPase family of enzymes was first identified >30 years ago and contains >20 members, which are divided into eight subfamilies: Cdc42, Rac, Rho, RhoUV, RhoBTB, RhoDF, RhoH, and Rnd. Rho GTPases are molecular on-off switches, which are increasingly being understood to have a critical role in a number of cellular processes, including cell migration, cell polarity, cell adhesion, cell cycle progression, and regulation of the cytoskeleton. This switch is an evolutionarily conserved system in which GTPases alternate between GDP-bound (inactive) and GTP-bound (active) forms. The activities of these Rho GTPases are many, context-dependent, and regulated by a number of proteins that are being progressively elucidated. Aberrations of the Rho GTPase signalling pathways have been implicated in various malignancies, including urothelial carcinoma, and understanding of the role of Rho GTPases in these diseases is increasing. This signalling pathway has the potential for therapeutic targeting in urothelial carcinoma. Research in this area is nascent, and much work is necessary before current laboratory-based research can be translated into the clinic.
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Affiliation(s)
- Solomon L Woldu
- University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9110, USA
| | - Ryan C Hutchinson
- University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9110, USA
| | - Laura-Maria Krabbe
- University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9110, USA
| | - Oner Sanli
- University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9110, USA
| | - Vitaly Margulis
- University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9110, USA
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24
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Nomikou E, Stournaras C, Kardassis D. Functional analysis of the promoters of the small GTPases RhoA and RhoB in embryonic stem cells. Biochem Biophys Res Commun 2017; 491:754-759. [PMID: 28739254 DOI: 10.1016/j.bbrc.2017.07.114] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 07/20/2017] [Indexed: 01/01/2023]
Abstract
Small GTPases of the Rho subfamily have been implicated in many physiological and pathological processes in various cell types including embryonic stem cells (ESCs). In the present study we performed a functional analysis of the promoters of the RhoA and the RhoB genes in order to identify regulatory elements that are important for their transcriptional control in ESCs. We show that RhoA mRNA levels were significantly higher compared with the RhoB mRNA levels in ESCs as well in various cancer cell lines and this difference could be accounted for by differences in the activities of the corresponding promoters. Deletion analysis of the RhoA and RhoB promoters in ESCs revealed that the proximal regions contain regulatory elements that are critical for their activity. Both proximal promoters contain CCAAT boxes and mutagenesis of these elements decreased significantly the activity of both promoters suggesting a coordinated regulation of the two genes by CCAAT box binding factors. Finally, we show that both genes are subjects to autoregulation in ESCs and in the case of RhoB, this autoregulation requires the GTPase activity of the Rho proteins. Understanding the mechanisms that control the transcription of Rho GTPases in ESCs may shed new light into the still unknown roles of these proteins in stem cell functions.
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Affiliation(s)
- Eirini Nomikou
- Laboratory of Biochemistry, Division of Basic Medical Sciences, University of Crete Medical School, Heraklion 71003, Greece
| | - Christos Stournaras
- Laboratory of Biochemistry, Division of Basic Medical Sciences, University of Crete Medical School, Heraklion 71003, Greece
| | - Dimitris Kardassis
- Laboratory of Biochemistry, Division of Basic Medical Sciences, University of Crete Medical School, Heraklion 71003, Greece; Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology of Hellas, Heraklion 71003, Greece.
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25
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Liu D, Mei X, Wang L, Yang X. RhoA inhibits apoptosis and increases proliferation of cultured SPCA1 lung cancer cells. Mol Med Rep 2017; 15:3963-3968. [PMID: 28487954 PMCID: PMC5436147 DOI: 10.3892/mmr.2017.6545] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 01/18/2017] [Indexed: 01/08/2023] Open
Abstract
The Rho kinase pathway has previously been reported to possess a close relationship with the growth, migration and invasion of lung cancer cells. However, the molecular mechanisms underlying the effects of this pathway on lung cancer cells are still elusive. The aim of the present study was to investigate the effects and underlying molecular mechanisms of Ras homolog family member A (RhoA) on the proliferation and apoptosis of SPCA1 lung carcinoma cells. Stable SPCA1 lung cancer cell lines, in which RhoA expression was silenced by small interfering RNA, were isolated following Geneticin screening. Inhibition of RhoA expression significantly decreased the proliferation of SPCA1 lung cancer cells, whereas apoptosis was significantly increased (P<0.01) as determined by the MTS tetrazolium assay and flow cytometry analysis, respectively. At the molecular level, knockdown of RhoA resulted in the significant activation of caspase-3 (P<0.01), and a significant reduction in the levels of phosphorylated signal transducer and activator of transcription (phospho-STAT3; P<0.01), as determined by western blotting. The results suggested that RhoA knockdown prevents cell proliferation and induces apoptosis in SPCA1 lung cancer cells. Furthermore, the underlying mechanisms responsible for these effects may include the activation of caspase-3 and the reduction of phospho-STAT3 levels.
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Affiliation(s)
- Dabei Liu
- Department of Thoracic Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110032, P.R. China
| | - Xingke Mei
- Department of Thoracic Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110032, P.R. China
| | - Linlin Wang
- Department of Thoracic Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110032, P.R. China
| | - Xueying Yang
- Department of Thoracic Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110032, P.R. China
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26
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Mevalonate Cascade Inhibition by Simvastatin Induces the Intrinsic Apoptosis Pathway via Depletion of Isoprenoids in Tumor Cells. Sci Rep 2017; 7:44841. [PMID: 28344327 PMCID: PMC5366866 DOI: 10.1038/srep44841] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 02/14/2017] [Indexed: 12/21/2022] Open
Abstract
The mevalonate (MEV) cascade is responsible for cholesterol biosynthesis and the formation of the intermediate metabolites geranylgeranylpyrophosphate (GGPP) and farnesylpyrophosphate (FPP) used in the prenylation of proteins. Here we show that the MEV cascade inhibitor simvastatin induced significant cell death in a wide range of human tumor cell lines, including glioblastoma, astrocytoma, neuroblastoma, lung adenocarcinoma, and breast cancer. Simvastatin induced apoptotic cell death via the intrinsic apoptotic pathway. In all cancer cell types tested, simvastatin-induced cell death was not rescued by cholesterol, but was dependent on GGPP- and FPP-depletion. We confirmed that simvastatin caused the translocation of the small Rho GTPases RhoA, Cdc42, and Rac1/2/3 from cell membranes to the cytosol in U251 (glioblastoma), A549 (lung adenocarcinoma) and MDA-MB-231(breast cancer). Simvastatin-induced Rho-GTP loading significantly increased in U251 cells which were reversed with MEV, FPP, GGPP. In contrast, simvastatin did not change Rho-GTP loading in A549 and MDA-MB-231. Inhibition of geranylgeranyltransferase I by GGTi-298, but not farnesyltransferase by FTi-277, induced significant cell death in U251, A549, and MDA-MB-231. These results indicate that MEV cascade inhibition by simvastatin induced the intrinsic apoptosis pathway via inhibition of Rho family prenylation and depletion of GGPP, in a variety of different human cancer cell lines.
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Macrophages Enhance Migration in Inflammatory Breast Cancer Cells via RhoC GTPase Signaling. Sci Rep 2016; 6:39190. [PMID: 27991524 PMCID: PMC5171813 DOI: 10.1038/srep39190] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 11/21/2016] [Indexed: 01/06/2023] Open
Abstract
Inflammatory breast cancer (IBC) is the most lethal form of breast cancer. All IBC patients have lymph node involvement and one-third of patients already have distant metastasis at diagnosis. This propensity for metastasis is a hallmark of IBC distinguishing it from less lethal non-inflammatory breast cancers (nIBC). Genetic profiling studies have been conducted to differentiate IBC from nIBC, but no IBC cancer-cell-specific gene signature has been identified. We hypothesized that a tumor-extrinsic factor, notably tumor-associated macrophages, promotes and contributes to IBC’s extreme metastatic phenotype. To this end, we studied the effect of macrophage-conditioned media (MCM) on IBC. We show that two IBC cell lines are hyper-responsive to MCM as compared to normal-like breast and aggressive nIBC cell lines. We further interrogated IBC’s hyper-responsiveness to MCM using a microfluidic migration device, which permits individual cell migration path tracing. We found the MCM “primes” the IBC cells’ cellular machinery to become extremely migratory in response to a chemoattractant. We determined that interleukins −6, −8, and −10 within the MCM are sufficient to stimulate this enhanced IBC migration effect, and that the known metastatic oncogene, RhoC GTPase, is necessary for the enhanced migration response.
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Zandvakili I, Lin Y, Morris JC, Zheng Y. Rho GTPases: Anti- or pro-neoplastic targets? Oncogene 2016; 36:3213-3222. [PMID: 27991930 PMCID: PMC5464989 DOI: 10.1038/onc.2016.473] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 11/04/2016] [Accepted: 11/07/2016] [Indexed: 02/06/2023]
Abstract
Rho GTPases are critical signal transducers of multiple pathways. They have been proposed to be useful anti-neoplastic targets for over two decades, especially in Ras-driven cancers. Until recently, however, few in vivo studies had been carried out to test this premise. Several recent mouse model studies have verified that Rac1, RhoA, and some of their effector proteins such as PAK and ROCK, are likely anti-cancer targets for treating K-Ras-driven tumors. Other seemingly contradictory studies have suggested that at least in certain instances inhibition of individual Rho GTPases may paradoxically result in pro-neoplastic effects. Significantly, both RhoA GTPase gain- and loss-of-function mutations have been discovered in primary leukemia/lymphoma and gastric cancer by human cancer genome sequencing efforts, suggesting both pro- and anti-neoplastic roles. In this review we summarize and integrate these unexpected findings and discuss the mechanistic implications in the design and application of Rho GTPase targeting strategies in future cancer therapies.
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Affiliation(s)
- I Zandvakili
- Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Molecular and Developmental Biology Graduate Program, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Medical-Scientist Training Program, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Y Lin
- Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - J C Morris
- Division of Hematology-Oncology, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio USA
| | - Y Zheng
- Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Molecular and Developmental Biology Graduate Program, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Medical-Scientist Training Program, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
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Zhao JW, Fang F, Guo Y, Zhu TL, Yu YY, Kong FF, Han LF, Chen DS, Li F. HPV16 integration probably contributes to cervical oncogenesis through interrupting tumor suppressor genes and inducing chromosome instability. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2016; 35:180. [PMID: 27884161 PMCID: PMC5123399 DOI: 10.1186/s13046-016-0454-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 11/09/2016] [Indexed: 12/11/2022]
Abstract
Background The integration of human papilloma virus (HPV) into host genome is one of the critical steps that lead to the progression of precancerous lesion into cancer. However, the mechanisms and consequences of such integration events are poorly understood. This study aims to explore those questions by studying high risk HPV16 integration in women with cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma (SCC). Methods Specifically, HPV integration status of 13 HPV16-infected patients were investigated by ligation-mediated PCR (DIPS-PCR) followed by DNA sequencing. Results In total, 8 HPV16 integration sites were identified inside or around genes associated with cancer development. In particular, the well-studied tumor suppressor genes SCAI was found to be integrated by HPV16, which would likely disrupt its expression and therefore facilitate the migration of tumor. On top of that, we observed several cases of chromosome translocation events coincide with HPV integration, which suggests the existence of chromosome instability. Additionally, short overlapping sequences were observed between viral derived and host derived fragments in viral-cellular junctions, indicating that integration was mediated by micro homology-mediated DNA repair pathway. Conclusions Overall, our study suggests a model in which HPV16 might contribute to oncogenesis not only by disrupting tumor suppressor genes, but also by inducing chromosome instability. Electronic supplementary material The online version of this article (doi:10.1186/s13046-016-0454-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jun-Wei Zhao
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China
| | - Fang Fang
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China
| | - Yi Guo
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China
| | - Tai-Lin Zhu
- Abbey College Cambridge, Homerton Gardens, Cambridge, CB2 8EB, UK
| | - Yun-Yun Yu
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China
| | - Fan-Fei Kong
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China
| | - Ling-Fei Han
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China
| | - Dong-Sheng Chen
- Department of Genetics, University of Cambridge, Cambridge, CB2 3EH, UK. .,Fitzwilliam College, University of Cambridge, Storey's Way, Cambridge, CB3 0DG, UK.
| | - Fang Li
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 200040, China.
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Ansari SS, Akgün N, Berger MR. Erufosine increases RhoB expression in oral squamous carcinoma cells independent of its tumor suppressive mode of action - a short report. Cell Oncol (Dordr) 2016; 40:89-96. [DOI: 10.1007/s13402-016-0302-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2016] [Indexed: 12/14/2022] Open
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Wu M, Hamaker M, Li L, Small D, Duffield AS. DOCK2 interacts with FLT3 and modulates the survival of FLT3-expressing leukemia cells. Leukemia 2016; 31:688-696. [PMID: 27748370 PMCID: PMC5332301 DOI: 10.1038/leu.2016.284] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 08/12/2016] [Accepted: 09/14/2016] [Indexed: 12/15/2022]
Abstract
The FMS-like tyrosine kinase-3 (FLT3) gene is the most commonly mutated gene in acute myeloid leukemia (AML), and patients carrying internal tandem duplication (ITD) mutations have a poor prognosis. Long-term inhibition of FLT3 activity in these patients has been elusive. To provide a more complete understanding of FLT3 biology, a mass spectroscopy-based screen was performed to search for FLT3-interacting proteins. The screen identified dedicator of cytokinesis 2 (DOCK2), which is a guanine nucleotide exchange factor for Rho GTPases, and its expression is limited to hematolymphoid cells. We show that DOCK2 is expressed in leukemia cell lines and primary AML samples, and DOCK2 co-immunoprecipitates with wild-type FLT3 and FLT3/ITD. Knock-down (KD) of DOCK2 by shRNA selectively reduced cell proliferation and colony formation in leukemia cell lines with increased FLT3 activity, and greatly sensitized these cells to cytarabine treatment, alone and in combination with FLT3 tyrosine kinase inhibitors. DOCK2 KD in a FLT3/ITD-positive leukemia cell line also significantly prolonged survival in a mouse xenograft model. These findings suggest that DOCK2 is a potential therapeutic target for novel AML treatments, as this protein regulates the survival of leukemia cells with elevated FLT3 activity and sensitizes FLT3/ITD leukemic cells to conventional anti-leukemic agents.
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Affiliation(s)
- M Wu
- Department of Pathology, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - M Hamaker
- Department of Pathology, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - L Li
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - D Small
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - A S Duffield
- Department of Pathology, The Johns Hopkins Hospital, Baltimore, MD, USA
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Could drugs inhibiting the mevalonate pathway also target cancer stem cells? Drug Resist Updat 2016; 25:13-25. [PMID: 27155373 DOI: 10.1016/j.drup.2016.02.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 12/12/2015] [Accepted: 01/28/2016] [Indexed: 02/07/2023]
Abstract
Understanding the connection between metabolic pathways and cancer is very important for the development of new therapeutic approaches based on regulatory enzymes in pathways associated with tumorigenesis. The mevalonate cascade and its rate-liming enzyme HMG CoA-reductase has recently drawn the attention of cancer researchers because strong evidences arising mostly from epidemiologic studies, show that it could promote transformation. Hence, these studies pinpoint HMG CoA-reductase as a candidate proto-oncogene. Several recent epidemiological studies, in different populations, have proven that statins are beneficial for the treatment-outcome of various cancers, and may improve common cancer therapy strategies involving alkylating agents, and antimetabolites. Cancer stem cells/cancer initiating cells (CSC) are key to cancer progression and metastasis. Therefore, in the current review we address the different effects of statins on cancer stem cells. The mevalonate cascade is among the most pleiotropic, and highly interconnected signaling pathways. Through G-protein-coupled receptors (GRCP), it integrates extra-, and intracellular signals. The mevalonate pathway is implicated in cell stemness, cell proliferation, and organ size regulation through the Hippo pathway (e.g. Yap/Taz signaling axis). This pathway is a prime preventive target through the administration of statins for the prophylaxis of obesity-related cardiovascular diseases. Its prominent role in regulation of cell growth and stemness also invokes its role in cancer development and progression. The mevalonate pathway affects cancer metastasis in several ways by: (i) affecting epithelial-to-mesenchymal transition (EMT), (ii) affecting remodeling of the cytoskeleton as well as cell motility, (iii) affecting cell polarity (non-canonical Wnt/planar pathway), and (iv) modulation of mesenchymal-to-epithelial transition (MET). Herein we provide an overview of the mevalonate signaling network. We then briefly highlight diverse functions of various elements of this mevalonate pathway. We further discuss in detail the role of elements of the mevalonate cascade in stemness, carcinogenesis, cancer progression, metastasis and maintenance of cancer stem cells.
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Zuo Y, Wu Y, Wehrli B, Chakrabarti S, Chakraborty C. Modulation of ERK5 is a novel mechanism by which Cdc42 regulates migration of breast cancer cells. J Cell Biochem 2016; 116:124-32. [PMID: 25160664 DOI: 10.1002/jcb.24950] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 08/22/2014] [Indexed: 11/09/2022]
Abstract
Members of Rho family GTPases including Cdc42 are known to play pivotal roles in cell migration. Cell migration is also known to be regulated by many protein kinases. Kinetworks KPSS 11.0 phospho-site screening of Cdc42-silenced Hs578T breast cancer cells revealed most dramatic change in ERK5 MAP kinase. In the present study, we set out to determine the relationship between Cdc42 and ERK5 and its significance in breast cancer cell migration and invasion. Specific siRNAs were used for knocking down Cdc42 or ERK5 in breast cancer cells. Increased ERK5 phosphorylation in breast cancer cells was achieved by infection of constitutively active MEK5 adenovirus. The cells were then subjected to cell migration or invasion assay without the presence of serum or any growth factor. We found that Cdc42 negatively regulated phosphorylation of ERK5, which in turn exhibited an inverse relationship with migration and invasiveness of breast cancer cells. To find out some in vivo relevance of the results of our in vitro experiments we also examined the expression of ERK5 in the breast cancer tissues and their adjacent normal control tissues by real-time RT-PCR and immunocytochemistry. ERK5 expression was found to be reduced in breast cancer tissues as compared with their adjacent uninvolved mammary tissues. Therefore, Cdc42 may promote breast cancer cell migration and invasion by inhibiting ERK5 phosphorylation and ERK5 expression may be inversely correlated with the progression of some breast tumors.
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Affiliation(s)
- Yufeng Zuo
- Department of Pathology, University of Western Ontario, London, Ontario, Canada
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Koo PK, Weitzman M, Sabanaygam CR, van Golen KL, Mochrie SGJ. Extracting Diffusive States of Rho GTPase in Live Cells: Towards In Vivo Biochemistry. PLoS Comput Biol 2015; 11:e1004297. [PMID: 26512894 PMCID: PMC4626024 DOI: 10.1371/journal.pcbi.1004297] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 04/26/2015] [Indexed: 11/19/2022] Open
Abstract
Resolving distinct biochemical interaction states when analyzing the trajectories of diffusing proteins in live cells on an individual basis remains challenging because of the limited statistics provided by the relatively short trajectories available experimentally. Here, we introduce a novel, machine-learning based classification methodology, which we call perturbation expectation-maximization (pEM), that simultaneously analyzes a population of protein trajectories to uncover the system of diffusive behaviors which collectively result from distinct biochemical interactions. We validate the performance of pEM in silico and demonstrate that pEM is capable of uncovering the proper number of underlying diffusive states with an accurate characterization of their diffusion properties. We then apply pEM to experimental protein trajectories of Rho GTPases, an integral regulator of cytoskeletal dynamics and cellular homeostasis, in vivo via single particle tracking photo-activated localization microcopy. Remarkably, pEM uncovers 6 distinct diffusive states conserved across various Rho GTPase family members. The variability across family members in the propensities for each diffusive state reveals non-redundant roles in the activation states of RhoA and RhoC. In a resting cell, our results support a model where RhoA is constantly cycling between activation states, with an imbalance of rates favoring an inactive state. RhoC, on the other hand, remains predominantly inactive. Single particle tracking is a powerful tool that captures the diffusive dynamics of proteins as they undergo various interactions in living cells. Uncovering different biochemical interactions by analyzing the diffusive behaviors of individual protein trajectories, however, is challenging due to the limited statistics provided by short trajectories and experimental noise sources which are intimately coupled into each protein’s localization. Here, we introduce a novel, unsupervised, machine-learning based classification methodology, which we call perturbation expectation-maximization (pEM), that simultaneously analyzes a population of protein trajectories to uncover the system of diffusive behaviors which collectively result from distinct biochemical interactions. We validate the performance of pEM in silico and in vivo on the biological system of Rho GTPase, a signal transduction protein responsible for regulating cytoskeletal dynamics. We envision that the presented methodology will be applicable to a wide range of single protein tracking data where different biochemical interactions result in distinct diffusive behaviors. More generally, this study brings us an important step closer to the possibility of monitoring the endogenous biochemistry of diffusing proteins within live cells with single molecule resolution.
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Affiliation(s)
- Peter K. Koo
- Department of Physics, Yale University, New Haven, Connecticut, United States of America
| | - Matthew Weitzman
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States of America
| | - Chandran R. Sabanaygam
- Delaware Biotechnology Institute, Bioimaging Center, Newark, Delaware, United States of America
| | - Kenneth L. van Golen
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States of America
| | - Simon G. J. Mochrie
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States of America
- Department of Applied Physics, Yale University, New Haven, Connecticut, United States of America
- * E-mail:
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Rho GTPases: Novel Players in the Regulation of the DNA Damage Response? Biomolecules 2015; 5:2417-34. [PMID: 26437439 PMCID: PMC4693241 DOI: 10.3390/biom5042417] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/02/2015] [Accepted: 09/09/2015] [Indexed: 12/26/2022] Open
Abstract
The Ras-related C3 botulinum toxin substrate 1 (Rac1) belongs to the family of Ras-homologous small GTPases. It is well characterized as a membrane-bound signal transducing molecule that is involved in the regulation of cell motility and adhesion as well as cell cycle progression, mitosis, cell death and gene expression. Rac1 also adjusts cellular responses to genotoxic stress by regulating the activity of stress kinases, including c-Jun-N-terminal kinase/stress-activated protein kinase (JNK/SAPK) and p38 kinases as well as related transcription factors. Apart from being found on the inner side of the outer cell membrane and in the cytosol, Rac1 has also been detected inside the nucleus. Different lines of evidence indicate that genotoxin-induced DNA damage is able to activate nuclear Rac1. The exact mechanisms involved and the biological consequences, however, are unclear. The data available so far indicate that Rac1 might integrate DNA damage independent and DNA damage dependent cellular stress responses following genotoxin treatment, thereby coordinating mechanisms of the DNA damage response (DDR) that are related to DNA repair, survival and cell death.
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Specific upregulation of RHOA and RAC1 in cancer-associated fibroblasts found at primary tumor and lymph node metastatic sites in breast cancer. Tumour Biol 2015; 36:9589-97. [PMID: 26142737 DOI: 10.1007/s13277-015-3727-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 06/28/2015] [Indexed: 12/21/2022] Open
Abstract
The importance of tumor-stromal cell interactions in breast tumor progression and invasion is well established. Here, an evaluation of differential genomic profiles of carcinoma-associated fibroblasts (CAFs) compared to fibroblasts derived from tissues adjacent to fibroadenomas (NAFs) revealed altered focal adhesion pathways. These data were validated through confocal assays. To verify the possible role of fibroblasts in lymph node invasion, we constructed a tissue microarray consisting of primary breast cancer samples and corresponding lymph node metastasis and compared the expression of adhesion markers RhoA and Rac1 in fibroblasts located at these different locations. Two distinct tissue microarrays were constructed from the stromal component of 43 primary tumors and matched lymph node samples, respectively. Fibroblasts were characterized for their expression of α-smooth muscle actin (α-SMA) and vimentin. Moreover, we verified the level of these proteins in the stromal compartment from normal adjacent tissue and in non-compromised lymph nodes. Our immunohistochemistry revealed that 59 % of fibroblasts associated with primary tumors and 41 % of the respective metastatic lymph nodes (p = 0.271) displayed positive staining for RhoA. In line with this, 57.1 % of fibroblasts associated with primary tumors presented Rac1-positive staining, and the frequency of co-positivity within the lymph nodes was 42.9 % (p = 0.16). Expression of RhoA and Rac1 was absent in fibroblasts of adjacent normal tissue and in compromised lymph nodes. Based on our findings that no significant changes were observed between primary and metastatic lymph nodes, we suggest that fibroblasts are active participants in the invasion of cancer cells to lymph nodes and support the hypothesis that metastatic tumor cells continue to depend on their microenvironment.
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Wang Y, Chen Y, Wu M, Lan T, Wu Y, Li Y, Qian H. Type II cyclic guanosine monophosphate-dependent protein kinase inhibits Rac1 activation in gastric cancer cells. Oncol Lett 2015; 10:502-508. [PMID: 26171059 DOI: 10.3892/ol.2015.3173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 03/27/2015] [Indexed: 12/13/2022] Open
Abstract
Enhanced motility of cancer cells is a critical step in promoting tumor metastasis, which remains the major cause of gastric cancer-associated mortality. The small GTPase Rac1 is a key signaling component in the regulation of cell migration. Previous studies have demonstrated that Rac1 activity may be regulated by protein kinase G (PKG); however, the underlying mechanism is not yet clear. The current study aimed to investigate the effect of type II cyclic guanosine monophosphate (cGMP)-dependent protein kinase (PKG II) on Rac1 activity. The human gastric cancer cell line AGS was infected with adenoviral constructs encoding PKG II to increase the expression of this enzyme, and treated with a cGMP analog (8-pCPT-cGMP) to induce its activation. A Transwell assay was employed to measure cell migration, and the activity of Rac1 was assessed using a pull-down assay. Immunoprecipitation was used to isolate the Rac1 protein. Phosphorylation of phosphatidylinositol 4,5 bisphosphate 3 kinase (PI3K) and its downstream effecter protein kinase B (Akt) are associated with lysophosphatidic acid (LPA)-induced motility/migration of cancer cells. Extracellular signal regulated kinase (ERK) is the major signaling molecule of the Mitogen activated protein kinase (MAPK) mediated signaling pathway. ERK and its upstream activator MAPK kinase (MEK) are also involved in LPA-induced motility/migration of cancer cells. Phosphorylation of PI3K/Akt, MEK/ERK and enriched Rac1 were detected by western blotting. The results revealed that blocking the activation of Rac1 by ectopically expressing an inactive Rac1 mutant (T17N) impeded LPA-induced cell migration. Increased PKG II activity inhibited LPA-induced migration and LPA-induced activation of Rac1; however, it had no effect on the phosphorylation of Rac1. PKG II also inhibited the activation of PI3K/Akt and MEK/ERK mediated signaling, which is important for LPA-induced Rac1 activation. These results suggest that PKG II affects LPA-stimulated migration of AGS cells by blocking Rac1 activation, via inhibition of PI3K/Akt and MEK/ERK mediated signaling.
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Affiliation(s)
- Ying Wang
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Yongchang Chen
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Min Wu
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Ting Lan
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Yan Wu
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Yueying Li
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Hai Qian
- Department of Physiology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
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Chang CH, Huang TF, Lin KT, Hsu CC, Chang WL, Wang SW, Ko FN, Peng HC, Chung CH. 4-Acetylantroquinonol B suppresses tumor growth and metastasis of hepatoma cells via blockade of translation-dependent signaling pathway and VEGF production. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:208-215. [PMID: 25494404 DOI: 10.1021/jf504434v] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Hepatocellular carcinoma (HCC) has become one of most common malignancies and a leading cause of cancer mortality worldwide. Previous study has shown that 4-acetylantroquinonol B (4AAQB) isolated from Antrodia cinnamomea (or niu-chang-chih) was observed to inhibit HepG2 cell proliferation via affecting cell cycle. However, the in vivo effects and antimetastatic activity of 4AAQB have not yet been addressed. This study found that 4AAQB inhibited HepG2 and HuH-7 hepatoma cell growth in both in vitro and in vivo models and exhibited pronounced inhibitory effects on HuH-7 tumor growth in xenograft and orthotopic models. 4AAQB efficiently inhibited the phosphorylation of mTOR and its upstream kinases and the downstream effectors and decreased the production of VEGF and activity of Rho GTPases in HuH-7 cells. Furthermore, 4AAQB inhibited in vitro HuH-7 cell migration and in vivo pulmonary metastasis. The results suggested that 4AAQB is a potential candidate for HCC therapy.
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Yang X, Zheng F, Zhang S, Lu J. Loss of RhoA expression prevents proliferation and metastasis of SPCA1 lung cancer cells in vitro. Biomed Pharmacother 2014; 69:361-6. [PMID: 25661383 DOI: 10.1016/j.biopha.2014.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 12/01/2014] [Indexed: 01/13/2023] Open
Abstract
Lung cancer is the leading cause of cancer-related death worldwide, mainly due to its highly metastatic properties. Previously, we reported an inverse correlation between Rho-kinase inhibitor and the progression of the lung cancer cells. The purpose of this study was to investigate the effects of RhoA on the proliferation, adhesion, invasion, and migration of SPCA1 lung carcinoma cells and to explore the underlying molecular mechanisms. RNA interference was used to downregulate RhoA expression in these cells. Through G418 screening, we generated SPCA1 lung cancer cell lines with stable RhoA silencing. We then observed the cell behaviour, and used matrix metalloproteinase (MMP) activity and western blot assays to evaluate the underlying molecular mechanisms. The proliferation, adhesion, migration, and invasion of SPCA1 lung cancer cells were decreased after knockdown of RhoA. At the molecular level, the total amounts of active MMP2 and MMP9 were decreased by about 17.21% (P<0.05) and 45.32% (P<0.01), respectively. Myosin phosphatase targeting subunit 1 phosphorylation (P-MYPT1) was reduced by 36.16% (P<0.05). Taken together, our findings show that the knockdown of RhoA prevents proliferation and metastasis in SPCA1 lung cancer cells. Changes in MMP2, MMP9, and P-MYPT1 levels and activity might be some of the molecular mechanisms underlying these effects.
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Affiliation(s)
- Xueying Yang
- Department of Thoracic Surgery, Shengjing Hospital, China Medical University, Shenyang, Liaoning, China
| | - Fushuang Zheng
- Department of Thoracic Surgery, Shengjing Hospital, China Medical University, Shenyang, Liaoning, China
| | - Suning Zhang
- Department of Thoracic Surgery, Shengjing Hospital, China Medical University, Shenyang, Liaoning, China
| | - Jibin Lu
- Department of Thoracic Surgery, Shengjing Hospital, China Medical University, Shenyang, Liaoning, China.
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Al-Jarallah A, Chen X, González L, Trigatti BL. High density lipoprotein stimulated migration of macrophages depends on the scavenger receptor class B, type I, PDZK1 and Akt1 and is blocked by sphingosine 1 phosphate receptor antagonists. PLoS One 2014; 9:e106487. [PMID: 25188469 PMCID: PMC4154704 DOI: 10.1371/journal.pone.0106487] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 08/04/2014] [Indexed: 01/12/2023] Open
Abstract
HDL carries biologically active lipids such as sphingosine-1-phosphate (S1P) and stimulates a variety of cell signaling pathways in diverse cell types, which may contribute to its ability to protect against atherosclerosis. HDL and sphingosine-1-phosphate receptor agonists, FTY720 and SEW2871 triggered macrophage migration. HDL-, but not FTY720-stimulated migration was inhibited by an antibody against the HDL receptor, SR-BI, and an inhibitor of SR-BI mediated lipid transfer. HDL and FTY720-stimulated migration was also inhibited in macrophages lacking either SR-BI or PDZK1, an adaptor protein that binds to SR-BI's C-terminal cytoplasmic tail. Migration in response to HDL and S1P receptor agonists was inhibited by treatment of macrophages with sphingosine-1-phosphate receptor type 1 (S1PR1) antagonists and by pertussis toxin. S1PR1 activates signaling pathways including PI3K-Akt, PKC, p38 MAPK, ERK1/2 and Rho kinases. Using selective inhibitors or macrophages from gene targeted mice, we demonstrated the involvement of each of these pathways in HDL-dependent macrophage migration. These data suggest that HDL stimulates the migration of macrophages in a manner that requires the activities of the HDL receptor SR-BI as well as S1PR1 activity.
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Affiliation(s)
- Aishah Al-Jarallah
- Department of Biochemistry and Biomedical Sciences, and the Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Xing Chen
- Department of Biochemistry and Biomedical Sciences, and the Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Leticia González
- Department of Biochemistry and Biomedical Sciences, and the Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Bernardo L. Trigatti
- Department of Biochemistry and Biomedical Sciences, and the Thrombosis and Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
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Asad M, Wong MK, Tan TZ, Choolani M, Low J, Mori S, Virshup D, Thiery JP, Huang RYJ. FZD7 drives in vitro aggressiveness in Stem-A subtype of ovarian cancer via regulation of non-canonical Wnt/PCP pathway. Cell Death Dis 2014; 5:e1346. [PMID: 25032869 PMCID: PMC4123093 DOI: 10.1038/cddis.2014.302] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/27/2014] [Accepted: 06/09/2014] [Indexed: 01/02/2023]
Abstract
Ovarian cancer (OC) can be classified into five biologically distinct molecular subgroups: epithelial-A (Epi-A), Epi-B, mesenchymal (Mes), Stem-A and Stem-B. Among them, Stem-A expresses genes relating to stemness and is correlated with poor clinical prognosis. In this study, we show that frizzled family receptor 7 (FZD7), a receptor for Wnt signalling, is overexpressed in the Stem-A subgroup. To elucidate the functional roles of FZD7, we used an RNA interference gene knockdown approach in three Stem-A cell lines: CH1, PA1 and OV-17R. Si-FZD7 OC cells showed reduced cell proliferation with an increase in the G0/G1 sub-population, with no effect on apoptosis. The cells also displayed a distinctive morphologic change by colony compaction to become more epithelial-like and polarised with smaller internuclear distances and increased z-axis height. Immunofluorescence (IF) staining patterns of pan-cadherin and β-catenin suggested an increase in cadherin-based cell–cell adhesion in si-FZD7 cells. We also observed a significant rearrangement in the actin cytoskeleton and an increase in tensile contractility in si-FZD7 OC cells, as evident by the loss of stress fibres and the redistribution of phospho-myosin light chain (pMLC) from the sites of cell–cell contacts to the periphery of cell colonies. Furthermore, there was reciprocal regulation of RhoA (Ras homolog family member A) and Rac1 (Ras-related C3 botulinum toxin substrate 1 (Rho family, small GTP-binding protein Rac1)) activities upon FZD7 knockdown, with a significant reduction in RhoA activity and a concomitant upregulation in Rac1 activity. These changes in pMLC and RhoA, as well as the increased TopFlash reporter activities in si-FZD7 cells, suggested involvement of the non-canonical Wnt/planar cell polarity (PCP) pathway. Selected PCP pathway genes (cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3), prickle homolog 4 (Drosophila) (PRICKLE4), dishevelled-associated activator of morphogenesis 1 (DAAM1), profilin 2 (PFN2), protocadherin 9 (PCDH9), protocadherin α1 (PCDHA1), protocadherin β17 pseudogene (PCDHB17), protocadherin β3 (PCDHB3), sprouty homolog 1 (SPRY1) and protein tyrosine kinase 7 (PTK7)) were found to be more highly expressed in Stem-A than non Stem-A subgroup of OC. Taken together, our results suggest that FZD7 might drive aggressiveness in Stem-A OC by regulating cell proliferation, cell cycle progression, maintenance of the Mes phenotype and cell migration via casein kinase 1ɛ-mediated non-canonical Wnt/PCP pathway.
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Affiliation(s)
- M Asad
- Cancer Science Institute of Singapore, Centre for Translational Medicine NUS Yong Loo Lin School of Medicine, Singapore, Singapore
| | - M K Wong
- Cancer Science Institute of Singapore, Centre for Translational Medicine NUS Yong Loo Lin School of Medicine, Singapore, Singapore
| | - T Z Tan
- Cancer Science Institute of Singapore, Centre for Translational Medicine NUS Yong Loo Lin School of Medicine, Singapore, Singapore
| | - M Choolani
- Department of Obstetrics and Gynaecology, National University Hospital of Singapore, Singapore, Singapore
| | - J Low
- 1] Department of Obstetrics and Gynaecology, National University Hospital of Singapore, Singapore, Singapore [2] National University Cancer Institute of Singapore, Singapore, Singapore
| | - S Mori
- Division of Cancer Genomics, Cancer Institute of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-Ku, Tokyo, Japan
| | - D Virshup
- Duke NUS Graduate Medical School, Singapore, Singapore
| | - J P Thiery
- 1] Cancer Science Institute of Singapore, Centre for Translational Medicine NUS Yong Loo Lin School of Medicine, Singapore, Singapore [2] National University Cancer Institute of Singapore, Singapore, Singapore [3] Department of Biochemistry, National University of Singapore, Singapore, Singapore [4] Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - R Y-J Huang
- 1] Cancer Science Institute of Singapore, Centre for Translational Medicine NUS Yong Loo Lin School of Medicine, Singapore, Singapore [2] Department of Obstetrics and Gynaecology, National University Hospital of Singapore, Singapore, Singapore [3] National University Cancer Institute of Singapore, Singapore, Singapore
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Liu Y, Song N, Ren K, Meng S, Xie Y, Long Q, Chen X, Zhao X. Expression loss and revivification of RhoB gene in ovary carcinoma carcinogenesis and development. PLoS One 2013; 8:e78417. [PMID: 24223801 PMCID: PMC3815309 DOI: 10.1371/journal.pone.0078417] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 09/20/2013] [Indexed: 12/23/2022] Open
Abstract
RhoB, a member of small GTPases belonging to the Ras protein superfamily, might have a suppressive activity in cancer progression. Here, expression of RhoB gene was evaluated in human benign, borderline and malignant ovary tumors by immunostaining, with normal ovary tissue as control. Malignant tumors were assessed according to Federation Internationale de Gynecologie Obstetrique (FIGO) guidelines and classified in stage I-IV. Revivification of RhoB gene was investigated by analyzing the effect of histone deacetylase (HDAC) inhibitor trichostatin (TSA) and methyltransferase inhibitor 5-azacytidine (5-Aza) on ovarian cancer cells via RT-PCR and western blot. Apoptosis of ovary cancer cells was detected using flowcytometry and fluorescence microscopy. Subsequently, RhoB expression is detected in normal ovary epithelium, borderline tumors, and decreases significantly or lost in the majority of ovarian cancer specimen (P<0.05). RhoB expression decreases significantly from stage II (71.4%) to stage III (43.5%) to stage IV (18.2%, P<0.05). TSA can both significantly revive the RhoB gene and mediate apoptosis of ovarian cancer cells, but 5-Aza couldn't. Interference into Revivification of RhoB gene results in reduction of ovary carcinoma cell apoptosis. It is proposed that loss of RhoB expression occurs frequently in ovary carcinogenesis and progression and its expression could be regulated by histone deacetylation but not by promoter hypermethylation, which may serve as a prospective gene treatment target for the patients with ovarian malignancy not responding to standard therapies.
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Affiliation(s)
- Yingwei Liu
- Department of Gynecology & Obstetrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Na Song
- National Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Kexing Ren
- National Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Shenglan Meng
- National Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Yao Xie
- Department of Gynecology & Obstetrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Qida Long
- Department of Gynecology & Obstetrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Xiancheng Chen
- National Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
- * E-mail: (XZ); chenwcrs @126.com (XC)
| | - Xia Zhao
- Department of Gynecology & Obstetrics, West China Second Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China
- * E-mail: (XZ); chenwcrs @126.com (XC)
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Opposing signaling of ROCK1 and ROCK2 determines the switching of substrate specificity and the mode of migration of glioblastoma cells. Mol Neurobiol 2013; 49:900-15. [PMID: 24170433 PMCID: PMC3950623 DOI: 10.1007/s12035-013-8568-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 10/02/2013] [Indexed: 01/29/2023]
Abstract
Despite current advances in therapy, the prognosis of patients with glioblastoma has not improved sufficiently in recent decades. This is due mainly to the highly invasive capacity of glioma cells. Little is known about the mechanisms underlying this particular characteristic. While the Rho-kinase (ROCK)-dependent signaling pathways involved in glioma migration have yet to be determined, they show promise as one of the candidates in targeted glioblastoma therapy. There are two ROCK isoforms: ROCK1, which is upregulated in glioblastoma tissue compared to normal brain tissue, and ROCK2, which is also expressed in normal brain tissue. Blockage of both of these ROCK isoforms with pharmacologic inhibitors regulates the migration process. We examined the activities of ROCK1 and ROCK2 using knockdown cell lines and the newly developed stripe assay. Selective knockdown of either ROCK1 or ROCK2 exerted antidromic effects on glioma migration: while ROCK1 deletion altered the substrate-dependent migration, deletion of ROCK2 did not. Furthermore, ROCK1 knockdown reduced cell proliferation, whereas ROCK2 knockdown enhanced it. Along the signaling pathways, key regulators of the ROCK pathway are differentially affected by ROCK1 and ROCK2. These data suggest that the balanced activation of ROCKs is responsible for the substrate-specific migration and the proliferation of glioblastoma cells.
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Abstract
The Rho family of GTPases (members of the Ras superfamily) are best known for their roles in regulating cytoskeletal dynamics. It is also well established that misregulation of Rho proteins contributes to tumorigenesis and metastasis. Unlike Ras proteins, which are frequently mutated in cancer (around 30%), Rho proteins themselves are generally not found to be mutated in cancer. Rather, misregulation of Rho activity in cancer was thought to occur by overexpression of these proteins or by misregulation of molecules that control Rho activity, such as activation or overexpression of GEFs and inactivation or loss of GAPs or GDIs. Recent studies, enabled by next-generation tumor exome sequencing, report activating point mutations in Rho GTPases as driver mutations in melanoma, as well as breast, and head and neck cancers. The Rac1(P29L) mutation identified in these tumor studies was previously identified by our lab as an activating Rac mutation in C. elegans neuronal development, highlighting the conserved nature of this mutation. Furthermore, this finding supports the relevance of studying Rho GTPases in model organisms such as C. elegans to study the mechanisms that underlie carcinogenesis. This review will describe the recent findings that report activating Rho mutations in various cancer types, moving Rho GTPases from molecules misregulated in cancer to mutagenic targets that drive tumorigenesis.
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Affiliation(s)
- Jamie K Alan
- Central Michigan University College of Medicine; Mt. Pleasant, MI USA
| | - Erik A Lundquist
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS USA
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45
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Alan JK, Struckhoff EC, Lundquist EA. Multiple cytoskeletal pathways and PI3K signaling mediate CDC-42-induced neuronal protrusion in C. elegans. Small GTPases 2013; 4:208-20. [PMID: 24149939 PMCID: PMC4011816 DOI: 10.4161/sgtp.26602] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 09/23/2013] [Accepted: 09/25/2013] [Indexed: 12/30/2022] Open
Abstract
Rho GTPases are key regulators of cellular protrusion and are involved in many developmental events including axon guidance during nervous system development. Rho GTPase pathways display functional redundancy in developmental events, including axon guidance. Therefore, their roles can often be masked when using simple loss-of-function genetic approaches. As a complement to loss-of-function genetics, we constructed a constitutively activated CDC-42(G12V) expressed in C. elegans neurons. CDC-42(G12V) drove the formation of ectopic lamellipodial and filopodial protrusions in the PDE neurons, which resembled protrusions normally found on migrating growth cones of axons. We then used a candidate gene approach to identify molecules that mediate CDC-42(G12V)-induced ectopic protrusions by determining if loss of function of the genes could suppress CDC-42(G12V). Using this approach, we identified 3 cytoskeletal pathways previously implicated in axon guidance, the Arp2/3 complex, UNC-115/abLIM, and UNC-43/Ena. We also identified the Nck-interacting kinase MIG-15/NIK and p21-activated kinases (PAKs), also implicated in axon guidance. Finally, PI3K signaling was required, specifically the Rictor/mTORC2 branch but not the mTORC1 branch that has been implicated in other aspects of PI3K signaling including stress and aging. Our results indicate that multiple pathways can mediate CDC-42-induced neuronal protrusions that might be relevant to growth cone protrusions during axon pathfinding. Each of these pathways involves Rac GTPases, which might serve to integrate the pathways and coordinate the multiple CDC-42 pathways. These pathways might be relevant to developmental events such as axon pathfinding as well as disease states such as metastatic melanoma.
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Affiliation(s)
| | - Eric C Struckhoff
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS USA
| | - Erik A Lundquist
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS USA
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46
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Phosphorylation of Rac1 T108 by extracellular signal-regulated kinase in response to epidermal growth factor: a novel mechanism to regulate Rac1 function. Mol Cell Biol 2013; 33:4538-51. [PMID: 24043306 DOI: 10.1128/mcb.00822-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Accumulating evidence has implicated Rho GTPases, including Rac1, in many aspects of cancer development. Recent findings suggest that phosphorylation might further contribute to the tight regulation of Rho GTPases. Interestingly, sequence analysis of Rac1 shows that Rac1 T108 within the (106)PNTP(109) motif is likely an extracellular signal-regulated kinase (ERK) phosphorylation site and that Rac1 also has an ERK docking site, (183)KKRKRKCLLL(192) (D site), at the C terminus. Indeed, we show here that both transfected and endogenous Rac1 interacts with ERK and that this interaction is mediated by its D site. Green fluorescent protein (GFP)-Rac1 is threonine (T) phosphorylated in response to epidermal growth factor (EGF), and EGF-induced Rac1 threonine phosphorylation is dependent on the activation of ERK. Moreover, mutant Rac1 with the mutation of T108 to alanine (A) is not threonine phosphorylated in response to EGF. In vitro ERK kinase assay further shows that pure active ERK phosphorylates purified Rac1 but not mutant Rac1 T108A. We also show that Rac1 T108 phosphorylation decreases Rac1 activity, partially due to inhibiting its interaction with phospholipase C-γ1 (PLC-γ1). T108 phosphorylation targets Rac1 to the nucleus, which isolates Rac1 from other guanine nucleotide exchange factors (GEFs) and hinders Rac1's role in cell migration. We conclude that Rac1 T108 is phosphorylated by ERK in response to EGF, which plays an important role in regulating Rac1.
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47
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Xu J, Zhou X, Wang J, Li Z, Kong X, Qian J, Hu Y, Fang JY. RhoGAPs attenuate cell proliferation by direct interaction with p53 tetramerization domain. Cell Rep 2013; 3:1526-38. [PMID: 23684608 DOI: 10.1016/j.celrep.2013.04.017] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 03/13/2013] [Accepted: 04/21/2013] [Indexed: 12/15/2022] Open
Abstract
Many Rho GTPase activation proteins (RhoGAPs) are deleted or downregulated in cancers, but the functional consequences are still unclear. Here, we show that the RhoGAP ArhGAP11A induces cell-cycle arrest and apoptosis by binding to the tumor suppressor p53. The RhoGAP domain of ArhGAP11A binds to the tetramerization domain of p53, but not to its family members p63 or p73. The interaction stabilizes the tetrameric conformation of p53 and enhances its DNA-binding activity, thereby inducing cell-cycle arrest and apoptosis. Upon DNA damage stress, ArhGAP11A accumulates in the nucleus and interacts with p53, whereas knockdown of ArhGAP11A partially blocks p53 transcriptional activity. These findings explain why RhoGAPs are frequently deleted in cancers and suggest that the RhoGAP family sits at the crossroads between the cell-migration and proliferation pathways.
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Affiliation(s)
- Jie Xu
- State Key Laboratory for Oncogenes and Related Genes, Division of Gastroenterology and Hepatology, Renji Hospital, Shanghai Institute for Digestive Diseases, Shanghai Jiao-Tong University School of Medicine, Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, 145 Middle Shandong Road, Shanghai 200001, China.
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Drosophila actin-Capping Protein limits JNK activation by the Src proto-oncogene. Oncogene 2013; 33:2027-39. [PMID: 23644660 DOI: 10.1038/onc.2013.155] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 03/27/2013] [Accepted: 03/28/2013] [Indexed: 12/17/2022]
Abstract
The Src family kinases c-Src, and its downstream effectors, the Rho family of small GTPases RhoA and Jun N-terminal kinase (JNK) have a significant role in tumorigenesis. In this report, using the Drosophila wing disc epithelium as a model system, we demonstrate that the actin-Capping Protein (CP) αβ heterodimer, which regulates actin filament (F-actin) polymerization, limits Src-induced apoptosis or tissue overgrowth by restricting JNK activation. We show that overexpressing Src64B drives JNK-independent loss of epithelial integrity and JNK-dependent apoptosis via Btk29A, p120ctn and Rho1. However, when cells are kept alive with the Caspase inhibitor P35, JNK acts as a potent inducer of proliferation via activation of the Yorkie oncogene. Reducing CP levels direct apoptosis of overgrowing Src64B-overexpressing tissues. Conversely, overexpressing capping protein inhibits Src64B and Rho1, but not Rac1-induced JNK signaling. CP requires the actin-binding domain of the α-subunit to limit Src64B-induced apoptosis, arguing that the control of F-actin mediates this effect. In turn, JNK directs F-actin accumulation. Moreover, overexpressing capping protein also prevents apoptosis induced by ectopic JNK expression. Our data are consistent with a model in which the control of F-actin by CP limits Src-induced apoptosis or tissue overgrowth by acting downstream of Btk29A, p120ctn and Rho1, but upstream of JNK. In turn, JNK may counteract the effect of CP on F-actin, providing a positive feedback, which amplifies JNK activation. We propose that cytoskeletal changes triggered by misregulation of F-actin modulators may have a significant role in Src-mediated malignant phenotypes during the early stages of cellular transformation.
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Goicoechea SM, García-Mata R, Staub J, Valdivia A, Sharek L, McCulloch CG, Hwang RF, Urrutia R, Yeh JJ, Kim HJ, Otey CA. Palladin promotes invasion of pancreatic cancer cells by enhancing invadopodia formation in cancer-associated fibroblasts. Oncogene 2013; 33:1265-73. [PMID: 23524582 DOI: 10.1038/onc.2013.68] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 12/17/2012] [Accepted: 01/25/2013] [Indexed: 12/29/2022]
Abstract
The stromal compartment surrounding epithelial-derived pancreatic tumors is thought to have a key role in the aggressive phenotype of this malignancy. Emerging evidence suggests that cancer-associated fibroblasts (CAFs), the most abundant cells in the stroma of pancreatic tumors, contribute to the tumor's invasion, metastasis and resistance to therapy, but the precise molecular mechanisms that regulate CAFs behavior are poorly understood. In this study, we utilized immortalized human pancreatic CAFs to investigate molecular pathways that control the matrix-remodeling and invasion-promoting activity of CAFs. We showed previously that palladin, an actin-associated protein, is expressed at high levels in CAFs of pancreatic tumors and other solid tumors, and also in an immortalized line of human CAFs. In this study, we found that short-term exposure of CAFs to phorbol esters reduced the number of stress fibers and triggered the appearance of individual invadopodia and invadopodial rosettes in CAFs. Molecular analysis of invadopodia revealed that their composition resembled that of similar structures (that is, invadopodia and podosomes) described in other cell types. Pharmacological inhibition and small interfering RNA knockdown experiments demonstrated that protein kinase C, the small GTPase Cdc42 and palladin were necessary for the efficient assembly of invadopodia by CAFs. In addition, GTPase activity assays showed that palladin contributes to the activation of Cdc42. In mouse xenograft experiments using a mixture of CAFs and tumor cells, palladin expression in CAFs promoted the rapid growth and metastasis of human pancreatic tumor cells. Overall, these results indicate that high levels of palladin expression in CAFs enhance their ability to remodel the extracellular matrix by regulating the activity of Cdc42, which in turn promotes the assembly of matrix-degrading invadopodia in CAFs and tumor cell invasion. Together, these results identify a novel molecular signaling pathway that may provide new molecular targets for the inhibition of pancreatic cancer metastasis.
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Affiliation(s)
- S M Goicoechea
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - R García-Mata
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - J Staub
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - A Valdivia
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - L Sharek
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - C G McCulloch
- CIHR Group in Matrix Dynamics, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
| | - R F Hwang
- Department of Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - R Urrutia
- Department of Biochemistry and Molecular Biology, Epigenetics and Chromatin Dynamics Laboratory, Division of Gastroenterology and Hepatology, Translational Epigenomics Program, Center for Individualized Medicine (CIM), Mayo Clinic, Rochester, MN, USA
| | - J J Yeh
- 1] Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA [2] Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA [3] Department of Surgery, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - H J Kim
- 1] Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA [2] Department of Surgery, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - C A Otey
- 1] Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA [2] Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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50
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Sukocheva O, Wadham C, Xia P. Estrogen defines the dynamics and destination of transactivated EGF receptor in breast cancer cells: role of S1P₃ receptor and Cdc42. Exp Cell Res 2013; 319:455-65. [PMID: 23142484 DOI: 10.1016/j.yexcr.2012.10.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 10/19/2012] [Accepted: 10/20/2012] [Indexed: 02/08/2023]
Abstract
Sphingosine-1-phosphate (S1P) receptors mediate transactivation of epidermal growth factor receptor (EGFR) by estrogen (E2). Here we report that the amount of intracellular EGFR remains elevated after stimulation of MCF-7 cells with E2 and S1P, although membrane-localized EGFR and S1P3 receptors are quickly internalized. Co-localization of internalized EGFR and LAMP-2 was lower in cells treated with E2/S1P, suggesting that endosomal EGFR might be directed for recycling instead of degradation. In addition, we found that E2/S1P activated Cdc42 and that knockdown of Cdc42 restores fast EGFR degradation after E2/S1P stimulation. Inhibition of S1P3 receptors prevented E2-induced activation of Cdc42, supporting the important role of the S1P receptor in E2 signaling. This is a novel mechanism further defining the effect of E2/S1P on the EGFR transactivation in breast cancer cells.
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Affiliation(s)
- O Sukocheva
- Flinders Centre for Cancer Prevention and Control, Division of Surgery, Flinders University, Bedford Park, SA 5042, Australia.
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