α-Actinin-4 promotes metastasis in gastric cancer

MAZ promotes thyroid cancer progression by driving transcriptional reprogram and enhancing ERK1/2 activation

Papillary thyroid carcinoma (PTC) is the most common type of thyroid malignancies worldwide. Oncogenic transcription factors (TFs) drive transcriptional reprogramming and tumorigenesis. The myc-associated zinc finger protein (MAZ) is one of the Myc family TFs. The role of MAZ in PTC pathogenesis is still largely unknown. Here, we report that MAZ profoundly promotes proliferation of PTC cells ex vivo and in vivo through activating MAPK signaling. We firstly profiled gene expression of PTC cells after silencing of MAZ. BRAF, KRAS and LOC547 were identified as important target genes of TF MAZ. In particular, TF MAZ bound to the promoters of BRAF or KRAS and significantly increased their transcription and expression levels. Meanwhile, MAZ could noticeably elevate LOC547 transcription and expression as a TF. High levels of LOC547 relocated ACTN4 protein from the nucleus to the cytosol, improved protein-protein interactions between ACTN4 and EGFR in the cytosol, enhanced ERK1/2 phosphorylation, activated the MAPK signaling and, thus, promoted PTC progression. Our data identify a previously underappreciated MAZ-controlled transcriptional reprogram and ERK1/2 activation via BRAF, KRAS and LOC547. Our data illustrate that activation of the MAZ-controlled axis promotes thyroid tumorigenesis. These insights would advance our knowledge of the role of TFs in cancer development and highlight the potential of TFs as future targets for treatments against cancers.

Live-cell imaging and CLEM reveal the existence of ACTN4-dependent ruffle-edge lamellipodia acting as a novel mode of cell migration

α-Actinin-4 (ACTN4) expression levels are correlated with the invasive and metastatic potential of cancer cells; however, the underlying mechanism remains unclear. Here, we identified ACTN4-localized ruffle-edge lamellipodia using live-cell imaging and correlative light and electron microscopy (CLEM). BSC-1 cells expressing EGFP-ACTN4 showed that ACTN4 was most abundant in the leading edges of lamellipodia, although it was also present in stress fibers and focal adhesions. ACTN4 localization in lamellipodia was markedly diminished by phosphoinositide 3-kinase inhibition, whereas its localization in stress fibers and focal adhesions remained. Furthermore, overexpression of ACTN4, but not ACTN1, promoted lamellipodial formation. Live-cell analysis demonstrated that ACTN4-enriched lamellipodia are highly dynamic and associated with cell migration. CLEM revealed that ACTN4-enriched lamellipodia exhibit a characteristic morphology of multilayered ruffle-edges that differs from canonical flat lamellipodia. Similar ruffle-edge lamellipodia were observed in A549 and MDA-MB-231 invasive cancer cells. ACTN4 knockdown suppressed the formation of ruffle-edge lamellipodia and cell migration during wound healing in A549 monolayer cultures. Additionally, membrane-type 1 matrix metalloproteinase was observed in the membrane ruffles, suggesting that ruffle-edge lamellipodia have the ability to degrade the extracellular matrix and may contribute to active cell migration/invasion in certain cancer cell types.

Terpene extract from the stem of Celastrus orbiculatus inhibits actin cytoskeleton remodelling in gastric cancer cells by regulating the protein interaction between PTBP1 and ACTN4

Adjuvant chemoradiotherapy, molecular targeted therapy, and immunotherapy are frequently employed to extend the survival of patients with advanced gastric cancer (GC). However, most of these treatments have toxic side effects, drug resistance, and limited improvements in survival and quality of life. Therefore, it is crucial to discover and develop new medications targeting GC that are highly effective and have minimal toxicity. In previous studies, the total terpene extract from the stem of Celastrus orbiculatus demonstrated anti-GC activity; however, the specific mechanism was unclear. Our research utilising co-immunoprecipitation-mass spectrometry (Co-IP-MS), polypyrimidine tract binding protein 1 (ptbp1) clustered regularly interspaced short palindromic repeat-associated protein 9 (Cas9)-knockout (KO) mouse model, tissue microarray, and functional experiments suggests that alpha actinin-4 (ACTN4) could be a significant biomarker of GC. PTBP1 influences actin cytoskeleton restructuring in GC cells by interacting with ACTN4. Celastrus orbiculatus stem extract (COE) may directly target ACTN4 and affect the interaction between PTBP1 and ACTN4, thereby exerting anti-GC effects.

Stool Protein Mass Spectrometry Identifies Biomarkers for Early Detection of Diffuse-type Gastric Cancer

There is a high unmet need for early detection approaches for diffuse gastric cancer (DGC). We examined whether the stool proteome of mouse models of gastric cancer (GC) and individuals with hereditary diffuse gastric cancer (HDGC) have utility as biomarkers for early detection. Proteomic mass spectrometry of the stool of a genetically engineered mouse model driven by oncogenic KrasG12D and loss of p53 and Cdh1 in gastric parietal cells [known as Triple Conditional (TCON) mice] identified differentially abundant proteins compared with littermate controls. Immunoblot assays validated a panel of proteins, including actinin alpha 4 (ACTN4), N-acylsphingosine amidohydrolase 2 (ASAH2), dipeptidyl peptidase 4 (DPP4), and valosin-containing protein (VCP), as enriched in TCON stool compared with littermate control stool. Immunofluorescence analysis of these proteins in TCON stomach sections revealed increased protein expression compared with littermate controls. Proteomic mass spectrometry of stool obtained from patients with HDGC with CDH1 mutations identified increased expression of ASAH2, DPP4, VCP, lactotransferrin (LTF), and tropomyosin-2 relative to stool from healthy sex- and age-matched donors. Chemical inhibition of ASAH2 using C6 urea ceramide was toxic to GC cell lines and GC patient-derived organoids. This toxicity was reversed by adding downstream products of the S1P synthesis pathway, which suggested a dependency on ASAH2 activity in GC. An exploratory analysis of the HDGC stool microbiome identified features that correlated with patient tumors. Herein, we provide evidence supporting the potential of analyzing stool biomarkers for the early detection of DGC. Prevention Relevance: This study highlights a novel panel of stool protein biomarkers that correlate with the presence of DGC and has potential use as early detection to improve clinical outcomes.

Mechanotransduction and epigenetic modulations of chromatin: Role of mechanical signals in gene regulation

Mechanical forces may be generated within a cell due to tissue stiffness, cytoskeletal reorganization, and the changes (even subtle) in the cell's physical surroundings. These changes of forces impose a mechanical tension within the intracellular protein network (both cytosolic and nuclear). Mechanical tension could be released by a series of protein-protein interactions often facilitated by membrane lipids, lectins and sugar molecules and thus generate a type of signal to drive cellular processes, including cell differentiation, polarity, growth, adhesion, movement, and survival. Recent experimental data have accentuated the molecular mechanism of this mechanical signal transduction pathway, dubbed mechanotransduction. Mechanosensitive proteins in the cell's plasma membrane discern the physical forces and channel the information to the cell interior. Cells respond to the message by altering their cytoskeletal arrangement and directly transmitting the signal to the nucleus through the connection of the cytoskeleton and nucleoskeleton before the information despatched to the nucleus by biochemical signaling pathways. Nuclear transmission of the force leads to the activation of chromatin modifiers and modulation of the epigenetic landscape, inducing chromatin reorganization and gene expression regulation; by the time chemical messengers (transcription factors) arrive into the nucleus. While significant research has been done on the role of mechanotransduction in tumor development and cancer progression/metastasis, the mechanistic basis of force-activated carcinogenesis is still enigmatic. Here, in this review, we have discussed the various cues and molecular connections to better comprehend the cellular mechanotransduction pathway, and we also explored the detailed role of some of the multiple players (proteins and macromolecular complexes) involved in mechanotransduction. Thus, we have described an avenue: how mechanical stress directs the epigenetic modifiers to modulate the epigenome of the cells and how aberrant stress leads to the cancer phenotype.

Induction of filopodia formation by α-Actinin-2 via RelA with a feedforward activation loop promoting overt bone marrow metastasis of gastric cancer

BACKGROUND

Bone marrow metastasis (BMM) is underestimated in gastric cancer (GC). GC with BMM frequently complicate critical hematological abnormalities like diffused intravascular coagulation and microangiopathic hemolytic anemia, which constitute a highly aggressive GC (HAGC) subtype. HAGC present a very poor prognosis with peculiar clinical and pathological features when compared with not otherwise specified advanced GC (NAGC). But the molecular mechanisms underlying BMM from GC remain rudimentary.

METHODS

The transcriptomic difference between HAGC and NAGC were analyzed. Genes that were specifically upregulated in HAGC were identified, and their effect on cell migration and invasion was studied. The function of ACTN2 gene were confirmed by GC cell lines, bone-metastatic animal model and patients' tissues. Furthermore, the molecular mechanism of ACTN2 derived-BMM was explored by multiple immunofluorescence staining, western blot, chromatin immunoprecipitation, and luciferase reporter assays.

RESULTS

We elucidated the key mechanisms of BMM depending on the transcriptomic difference between HAGC and NAGC. Five genes specifically upregulated in HAGC were assessed their effect on cell migration and invasion. The ACTN2 gene encoding protein α-Actinin-2 was detected enhanced the metastatic capability and induced BMM of GC cells in mouse models. Mechanically, α-Actinin-2 was involved in filopodia formation where it promoted the Actin filament cross-linking by replacing α-Actinin-1 to form α-Actinin-2:α-Actinin-4 complexes in GC cells. Moreover, NF-κB subunit RelA and α-Actinin-2 formed heterotrimers in the nuclei of GC cells. As a direct target of RelA:α-Actinin-2 heterotrimers, the ACTN2 gene was a positive auto-regulatory loop for α-Actinin-2 expression.

CONCLUSIONS

We demonstrated a link between filopodia, BMM and ACTN2 activation, where a feedforward activation loop between ACTN2 and RelA is established via actin in response to distant metastasis. Given the novel filopodia formation function and the new mechanism of BMM in GC, we propose ACTN2 as a druggable molecular vulnerability that may provide potential therapeutic benefit against BMM of GC.

Cancer as a biophysical disease: Targeting the mechanical-adaptability program

With the number of cancer cases projected to significantly increase over time, researchers are currently exploring "nontraditional" research fields in the pursuit of novel therapeutics. One emerging area that is steadily gathering interest revolves around cellular mechanical machinery. When looking broadly at the physical properties of cancer, it has been debated whether a cancer could be defined as either stiffer or softer across cancer types. With numerous articles supporting both sides, the evidence instead suggests that cancer is not particularly regimented. Instead, cancer is highly adaptable, allowing it to endure the constantly changing microenvironments cancer cells encounter, such as tumor compression and the shear forces in the vascular system and body. What allows cancer cells to achieve this adaptability are the particular proteins that make up the mechanical network, leading to a particular mechanical program of the cancer cell. Coincidentally, some of these proteins, such as myosin II, α-actinins, filamins, and actin, have either altered expression in cancer and/or some type of direct involvement in cancer progression. For this reason, targeting the mechanical system as a therapeutic strategy may lead to more efficacious treatments in the future. However, targeting the mechanical program is far from trivial. As involved as the mechanical program is in cancer development and metastasis, it also helps drive many other key cellular processes, such as cell division, cell adhesion, metabolism, and motility. Therefore, anti-cancer treatments targeting the mechanical program must take great care to avoid potential side effects. Here, we introduce the potential of targeting the mechanical program while also providing its challenges and shortcomings as a strategy for cancer treatment.

LncRNA TP73-AS1 Exacerbates the Non-Small-Cell Lung Cancer (NSCLC) Process via Regulating miR-125a-3p-Mediated ACTN4

Background

LncRNA TP73-AS1 has been revealed to exert a noteworthy impact on the occurrence and advancement of different cancers. In this study, we explored the function of TP73-AS1 in tumor growth, cell progression as well as the relevant molecular mechanism in non-small-cell lung cancer (NSCLC).

Methods

QRT-PCR was employed to assess the expression of TP73-AS1, miR‐125a-3p, and actinin alpha 4 (ACTN4) in NSCLC cells. The biological effect of TP73-AS1 on NSCLC cells was assessed by cell transfection, CCK8, and transwell experiments. We further predicted the interaction among RNAs (TP73-AS1, miR-125a-3p, and ACTN4) through bioinformatics online tools and verified via luciferase reporter, RNA immunoprecipitation, and qRT-PCR assays. Xenograft models of SPC-A1 cells were conducted to test how TP73-AS1 regulates tumorigenesis. Western blot, as well as the immunohistochemistry (IHC) assays, was utilized to measure the expression levels. Functions of TP73-AS1 in NSCLC progression through the miR-125a-3p/ACTN4 axis were investigated by rescue experiments.

Results

Knockdown of TP73-AS1 suppressed the growth and simultaneously attenuated the migration and invasion ability of NSCLC SPC-A1 and A549 cells. Bioinformatics and molecular mechanism assays demonstrated that TP73-AS1 could bind to miR-125a-3p/ACTN4 and regulate their expression. Moreover, the rescued‐function experiment demonstrated that suppressing miR-125a-3p or elevating ACTN4 turned around the suppression effect of sh-TP73-AS1 on NSCLC progression. TP73-AS1 inhibition could also inhibit the NSCLC tumor growth and correspondingly regulated the expression of miR-125a-3p and ACTN4 in the tumor xenograft model.

Conclusion

The present study indicated that TP73-AS1 affects NSCLC progression through a new competitive RNA (ceRNA) regulatory network of miR-125a-3p/ACTN4, providing an underlying target for NSCLC treatment in the future.

CircCOL1A2 Sponges MiR-1286 to Promote Cell Invasion and Migration of Gastric Cancer by Elevating Expression of USP10 to Downregulate RFC2 Ubiquitination Level

Gastric cancers (GC) are generally malignant tumors, occurring with high incidence and threatening public health around the world. Circular RNAs (circRNAs) play crucial roles in modulating various cancers, including GC. However, the functions of circRNAs and their regulatory mechanism in colorectal cancer (CRC) remain largely unknown. This study focuses on both the role of circCOL1A2 in CRC progression as well as its downstream molecular mechanism. Quantitative polymerase chain reaction (qPCR) and western blot were adopted for gene expression analysis. Functional experiments were performed to study the biological functions. Fluorescence in situ hybridization (FISH) and subcellular fraction assays were employed to detect the subcellular distribution. Luciferase reporter, RNA-binding protein immunoprecipitation (RIP), co-immunoprecipitation (Co-IP), RNA pull-down, and immunofluorescence (IF) and immunoprecipitation (IP) assays were used to explore the underlying mechanisms. Our results found circCOL1A2 to be not only upregulated in GC cells, but that it also propels the migration and invasion of GC cells. CircCOL1A2 functions as a competing endogenous RNA (ceRNA) by sequestering microRNA-1286 (miR-1286) to modulate ubiquitin-specific peptidase 10 (USP10), which in turn spurs the migration and invasion of GC cells by regulating RFC2. In sum, CircCOL1A2 sponges miR-1286 to promote cell invasion and migration of GC by elevating the expression of USP10 to downregulate the level of RFC2 ubiquitination. Our study offers a potential novel target for the early diagnosis and treatment of GC.

Expressional and prognostic value of HPCAL1 in cholangiocarcinoma via integrated bioinformatics analyses and experiments

BACKGROUND

Hippocalcin-like 1 (HPCAL1) is involved in the development of several cancer types. However, our understanding of the HPCAL1 activity in cholangiocarcinoma (CCA) remains limited.

METHODS

Two microarray datasets were used to screen for differentially expressed genes (DEGs) involved in the development of CCA. The Cancer Genome Atlas (TCGA)/Gene Expression Omnibus (GEO) database was integrated to determine the prognostic significance of DEGs in CCA. The association between clinical characteristics and HPCAL1 expression levels was initially explored to assess the clinical profile of CCA. The prognostic value of HPCAL1 overexpression in the validation cohort was analyzed, followed by Gene Ontology (GO) term analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of HPCAL1.

RESULTS

Three upregulated genes and 10 downregulated genes were detected from two microarray-based screenings. High expression of HPCAL1 as a poor prognostic factor of CCA was validated using TCGA/GEO integrated database and our database. Univariate and multivariate analyses along with Kaplan-Meier survival analysis showed that high HPCAL1 expression was an independent factor affecting the overall survival and relapse-free survival in patients with CCA. The high expression of HPCAL1 was significantly associated with cancer antigen 125 (CA-125) levels, number of tumors, lymph node invasion, and TNM stage. Analysis of the enriched GO terms and KEGG pathways revealed that the high expression of HPCAL1 was involved in the critical biological processes and molecular pathways, including modulation by a host of symbiont processes, the clathrin coat, actinin binding, and Rap1 signaling pathways.

CONCLUSION

HPCAL1 was enriched in CCA in our study and has the potential to be applied in the identification of patients with CCA with an unfavorable prognosis.

H3K27ac-activated EGFR-AS1 promotes cell growth in cervical cancer through ACTN4-mediated WNT pathway

Background

Recently, extensive studies unveiled that lncRNAs exert critical function in the development and progression of cervical cancer (CC). EGFR-AS1 is a novel lncRNA which has not been well-explored in CC.

Aims

Our study aimed to research the function and molecular mechanism of EGFR-AS1 in CC cells. qRT-PCR analysis was performed to detect gene expression. Colony formation, EdU, flow cytometry, TUNEL, western blot and transwell assays were performed to assess the effect of EGFR-AS1 on CC cell growth. The regulatory mechanism of EGFR-AS1 was dug out through mechanism experiments.

Results

EGFR-AS1 was notably overexpressed in CC cell lines. Loss-of-functional experiments revealed that EGFR-AS1 promoted CC cell proliferation, migration and invasion, and suppressed cell apoptosis. Mechanistically, up-regulation of EGFR-AS1 was attributed to the activation of H3K27 acetylation (H3K27ac). Further, EGFR-AS1 was revealed to function as miR-2355-5p sponge. Additionally, miR-2355-5p was down-regulated in CC cells and ACTN4 was identified as a target gene of miR-2355-5p. Ultimately, overexpressed ACTN4 could reserve the suppressive role of EGFR-AS1 silencing in CC cell growth. Last but not least, EGFR-AS1 facilitated CC cell growth via ACTN4-mediated WNT pathway.

Conclusions

H3K27ac-activated EGFR-AS1 sponged miR-2355-5p and promoted CC cell growth through ACTN4-mediated WNT pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13062-021-00315-5.

Development of biomarkers for predicting recurrence by determining the metastatic ability of cancer cells

Adjuvant chemotherapy has been carried out for patients with cancer who underwent curative resection, but it is basically not needed for patients without micro-metastatic lesions who undergo a perfectly curative surgical operation. The patients who need adjuvant chemotherapy are defined as those whose micro-metastases cannot be detected by imaging modalities in the other sites of the resective areas, despite curative resection for the primary sites. If biomarkers to efficiently evaluate the metastatic potential of each patient could be developed, we may be able to provide personalized adjuvant chemotherapy in the clinical setting. Actinin-4 (ACTN4, gene name ACTN4) is an actin-bundling protein that we identified in 1998 as a novel molecule involved in cancer invasion and metastasis. Protein overexpression of actinin-4 in cancer cells leads to the invasive phenotype, and patients with gene amplification of ACTN4 have a worse prognosis than patients with a normal copy number in some cancers, including pancreas, lung, and salivary gland cancers. In this review, the biological roles of actinin-4 for cancer invasion and metastasis are summarized, and the potential usefulness of actinin-4 as a biomarker for evaluation of metastatic ability is examined.

L-Plastin Promotes Gastric Cancer Growth and Metastasis in a Helicobacter pylori cagA-ERK-SP1-Dependent Manner

Actin cytoskeleton dynamic rearrangement is required for tumor cell metastasis and is a key characteristic of Helicobacter pylori (H. pylori)-infected host cells. Actin cytoskeleton modulation is coordinated by multiple actin-binding proteins (ABP). Through Kyoto encyclopedia of gene and genomes database, GEPIA website, and real-time PCR data, we found that H. pylori infection significantly induced L-plastin, a key ABP, in gastric cancer cells. We further explored the regulation and function of L-plastin in H. pylori-associated gastric cancer and found that, mechanistically, H. pylori infection induced gastric cancer cells to express L-plastin via cagA-activated ERK signaling pathway to mediate SP1 binding to L-plastin promoter. Moreover, this increased L-plastin promoted gastric cancer cell proliferation and migration in vitro and facilitated the growth and metastasis of gastric cancer in vivo. Finally, we detected the expression pattern of L-plastin in gastric cancer tissues, and found that L-plastin was increased in gastric cancer tissues and that this increase of L-plastin positively correlated with cagA + H. pylori infection status. Overall, our results elucidate a novel mechanism of L-plastin expression induced by H. pylori, and a new function of L-plastin-facilitated growth and metastasis of gastric cancer, and thereby implicating L-plastin as a potential therapeutic target against gastric cancer. IMPLICATIONS: Our results elucidate a novel mechanism of L-plastin expression induced by H. pylori in gastric cancer, and a new function of L-plastin-facilitated gastric cancer growth and metastasis, implicating L-plastin as a potential therapeutic target against gastric cancer.

Proteomic analysis of TGFβ-induced A549 secretome identifies putative regulators of epithelial-mesenchymal transition

Imparting epithelial to mesenchymal transition (EMT) during cellular transformation, a major driving force behind tumor progression, is one of the notorious oncogenic activities of transforming growth factor β (TGFβ); however, the secretary factors released during TGFβ-induced EMT that may have role in potentiating EMT and tumor progression are poorly known. This study was undertaken to identify such secreted protein factors from TGFβ-induced A549 cells cultured in serum-free chemically defined medium (Freestyle^TM ) using Matrix Assisted Laser Desorption Ionization-Time of flight/Time of flight (MALDI-TOF/TOF) mass spectrometry. We identified some of the potential factors such as ESR, ANXA2, ALDH1A, TGFβ-induced protein ig-h3, and PAI-1 that were not only secreted but some were also elevated in TGFβ-induced A549 cells. Interestingly, these factors are widely reported to play crucial role in EMT induction and progression, which not only validates our findings but also opens avenues for further investigation, if upon secretion they act exogenously through certain receptors to potentiate cellular signaling involved in EMT induction and tumor progression.

Binding of alpha-ACTN4 to EGF receptor enables its rapid phosphorylation

Alpha-ACTN4, a member of alpha-actinin family is critical for cell motility through its regulated binding of actin filaments. We previously found that EGF exposure of cells triggers the tyrosyl-phosphorylation of ACTN4 in fibroblasts that dramatically downregulates its binding to actin filaments. However, the exact kinase remained uncertain. In the present study, we report that the phosphorylation of ACTN4 occurs within seconds upon EGF treatments and is accomplished via direct interaction of ACTN4 with the EGF receptor. The major binding domain of ACTN4 for EGF receptor is mapped to the N-terminal 32 amino acids. A second domain minimizes the interaction, as truncation of the C-terminal tail enhances ACTN4 binding to EGF receptor. A mimetic phosphorylated ACTN4, Y4/31E, presents low binding to EGF receptor. Overexpression of EGF receptor in melanoma cell lines, also accomplishes the phosphorylation of ACTN4 in the presence of EGF. These findings suggest that the binding of ACTN4 to EGFR enables its direct and rapid phosphorylation resulting in dissociation from EGFR and decreased binding to actin filaments.

Asiaticoside inhibits renal fibrosis development by regulating the miR-142-5p/ACTN4 axis

Renal fibrosis results in the progressive renal dysfunction and leads to chronic kidney disease (CKD) and ultimately end-stage renal disease. Asiaticoside was reported to regulate synaptopodin, desmin, nephrin, and podocin levels in adriamycin-induced nephropathy of rats. In this study, we found out that asiaticoside inhibited renal fibrosis in vitro and in vivo. Additionally, miR-142-5p was upregulated in in vitro and in vivo models of CKD. MiR-142-5p promoted the levels of collagen-I, collagen-IV, and fibronectin proteins. Additionally, miR-142-5p overexpression partly rescued the protective effect of asiaticoside on renal fibrosis. Mechanistically, miR-142-5p inhibited ACTN4 levels by binding with its 3´untranslated region, and further reduced its translation. Treatment of asiaticoside decreased miR-142-5p levels and increased ACTN4 levels. Rescue assays revealed that ACTN4 overexpression partially rescued the effect of miR-142-5p on renal fibrosis. Asiaticoside mitigated renal fibrosis by regulating the miR-142-5p/ACTN4 axis. In conclusion, asiaticoside inhibits renal fibrosis by regulating the miR-142-5p/ACTN4 axis. This novel discovery suggested that asiaticoside may serve as a potential medicine for renal fibrosis improvement.

Study on the regulatory mechanism and experimental verification of icariin for the treatment of ovarian cancer based on network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Herba Epimedii (Berberidaceae) has the advantages of "nourishing the kidney and reinforcing the Yang". Many species in this genus have long been used in traditional Chinese medicine (TCM) and have been used as anticancer drugs in traditional Chinese herbal medicine formulations. Icariin, a major flavonoid glycoside extracted from Epimedium brevicornum Maxim, has been widely proven to exert an inhibitory effect on ovarian cancer (OC), and icariin can induce apoptosis and inhibit invasion and migration. However, the underlying mechanism remains unclear, so further research is necessary to verify its traditional use.

AIM OF THE STUDY

This study aimed to explore the regulatory mechanism of icariin in the biological network and signalling pathway of OC through network pharmacology and cytological experiments.

METHODS

Public databases and R × 3.6.2 software were adopted to predict the potential targets, construct the protein-protein interaction (PPI) network, and perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. After the network pharmacological analysis, cytological experiments, real-time quantitative PCR (qPCR) and Western blot (WB) analyses were used to verify the key signalling pathway.

RESULTS

The targets related to treatment were TNF, MMP9, STAT3, PIK3CA, ERBB2, MTOR, IL2, PTGS2, KDR, and F2. GO and KEGG enrichment analyses indicated that various kinases and the PI3K/AKT signalling pathway were the most enriched molecules and pathways. Icariin inhibited OC SKOV3 cell proliferation, migration and invasion in vitro and promoted apoptosis by inhibiting the PI3K/AKT signalling pathway.

CONCLUSION

Icariin promotes apoptosis and suppresses SKOV3 cell activities through the PI3K-Akt signalling pathway. This research not only provides a theoretical and experimental basis for more in-depth studies but also offers an efficient method for the rational utilization of a series of icariin flavonoids as anti-tumour drugs.

The mechanobiome: a goldmine for cancer therapeutics

Cancer progression is dependent on heightened mechanical adaptation, both for the cells' ability to change shape and to interact with varying mechanical environments. This type of adaptation is dependent on mechanoresponsive proteins that sense and respond to mechanical stress, as well as their regulators. Mechanoresponsive proteins are part of the mechanobiome, which is the larger network that constitutes the cell's mechanical systems that are also highly integrated with many other cellular systems, such as gene expression, metabolism, and signaling. Despite the altered expression patterns of key mechanobiome proteins across many different cancer types, pharmaceutical targeting of these proteins has been overlooked. Here, we review the biochemistry of key mechanoresponsive proteins, specifically nonmuscle myosin II, α-actinins, and filamins, as well as the partnering proteins 14-3-3 and CLP36. We also examined a wide range of data sets to assess how gene and protein expression levels of these proteins are altered across many different cancer types. Finally, we determined the potential of targeting these proteins to mitigate invasion or metastasis and suggest that the mechanobiome is a goldmine of opportunity for anticancer drug discovery and development.

Involvement of Actin and Actin-Binding Proteins in Carcinogenesis

The actin cytoskeleton plays a crucial role in many cellular processes while its reorganization is important in maintaining cell homeostasis. However, in the case of cancer cells, actin and ABPs (actin-binding proteins) are involved in all stages of carcinogenesis. Literature has reported that ABPs such as SATB1 (special AT-rich binding protein 1), WASP (Wiskott-Aldrich syndrome protein), nesprin, and villin take part in the initial step of carcinogenesis by regulating oncogene expression. Additionally, changes in actin localization promote cell proliferation by inhibiting apoptosis (SATB1). In turn, migration and invasion of cancer cells are based on the formation of actin-rich protrusions (Arp2/3 complex, filamin A, fascin, α-actinin, and cofilin). Importantly, more and more scientists suggest that microfilaments together with the associated proteins mediate tumor vascularization. Hence, the presented article aims to summarize literature reports in the context of the potential role of actin and ABPs in all steps of carcinogenesis.

The Expressions and Mechanisms of Sarcomeric Proteins in Cancers

The sarcomeric proteins control the movement of cells in diverse species, whereas the deregulation can induce tumours in model organisms and occurs in human carcinomas. Sarcomeric proteins are recognized as oncogene and related to tumor cell metastasis. Recent insights into their expressions and functions have led to new cancer therapeutic opportunities. In this review, we appraise the evidence for the sarcomeric proteins as cancer genes and discuss cancer-relevant biological functions, potential mechanisms by which sarcomeric proteins activity is altered in cancer.

High ACTN1 Is Associated with Poor Prognosis, and ACTN1 Silencing Suppresses Cell Proliferation and Metastasis in Oral Squamous Cell Carcinoma

Purpose

Oral squamous cell carcinoma (OSCC) is a common malignancy of the oral cavity. As the survival rate of OSCC patients is low, it is crucial to explore new markers and therapeutic targets for early diagnosis of the disease. A high level of actinin alpha 1 (ACTN1) in patients could serve as an independent prognostic factor of acute myeloid leukemia. However, the role of ACTN1 in OSCC remains unclear. In the present study, we aimed to investigate the role of ACTN1 in OSCC.

Methods

ACTN1 protein levels in tissues were determined by immunohistochemical (IHC) staining. The correlation of ACTN1 expression with clinicopathological features and prognosis was analyzed. Univariate and multivariate analyses were performed. The effect of ACTN1 knockdown on cell proliferation, migration, invasion, apoptosis, epithelial-mesenchymal transition (EMT), and the cell cycle was evaluated using Western blotting, Cell Counting Kit‑8 (CCK8) assays, flow cytometry analysis, transwell assays, wound-healing assays, and nude mouse models of subcutaneous xenograft and pulmonary metastasis.

Results

Based on the total score of ACTN1 IHC staining analysis, ACTN1 expression was found to be low in 10 normal mucosal tissues, 48 normal mucosal tissues adjacent to OSCC, and 19 OSCC tissues, but high in 29 OSCC tissues. ACTN1 protein levels were significantly associated with the clinical stage and node metastasis, and a high ACTN1 protein level indicated poor prognosis. Moreover, ACTN1 expression was an independent predictor of poor prognosis of OSCC. Using in vitro assays, we found that ACTN1 knockdown could induce cell cycle arrest, promote apoptosis, and inhibit EMT and cell proliferation, migration, and invasion in the OSCC cell lines, SCC-15 and HSC-3. Moreover, ACTN1 knockdown inhibited subcutaneous tumor growth and pulmonary metastasis in vivo.

Conclusion

ACTN1 levels were significantly associated with the clinical stage and node metastasis, and a high ACTN1 protein level indicated poor prognosis. Moreover, ACTN1 knockdown could suppress cell proliferation and metastasis of OSCC. Our results suggested that ACTN1 may serve as a diagnostic and prognostic marker of OSCC.

Role of ACTN4 in Tumorigenesis, Metastasis, and EMT

The actin-binding protein ACTN4 belongs to a family of actin-binding proteins and is a non-muscle alpha-actinin that has long been associated with cancer development. Numerous clinical studies showed that changes in ACTN4 gene expression are correlated with aggressiveness, invasion, and metastasis in certain tumors. Amplification of the 19q chromosomal region where the gene is located has also been reported. Experimental manipulations with ACTN4 expression further confirmed its involvement in cell proliferation, motility, and epithelial-mesenchymal transition (EMT). However, both clinical and experimental data suggest that the effects of ACTN4 up- or down-regulation may vary a lot between different types of tumors. Functional studies demonstrated its engagement in a number of cytoplasmic and nuclear processes, ranging from cytoskeleton reorganization to regulation of different signaling pathways. Such a variety of functions may be the reason behind cell type and cell line specific responses. Herein, we will review research progress and controversies regarding the prognostic and functional significance of ACTN4 for tumorigenesis.

Elevated TRIP13 drives the AKT/mTOR pathway to induce the progression of hepatocellular carcinoma via interacting with ACTN4

BACKGROUND

ATPase associated with a variety of cellular activities (AAA ATPase) family members are closely linked to tumor formation and progression. However, their roles in hepatocellular carcinoma (HCC) largely remain unclear.

METHODS

Bioinformatic analyses of public databases were used to excavate the potential AAA ATPases that may contribute to HCC, and thyroid hormone receptor interactor 13 (TRIP13) was selected to following researches because of its most prominently differential expression. Western blot, qRT-PCR and immunohistochemistry were used to detect the expression of TRIP13 in HCC tissues, and then the relationship between TRIP13 expression and clinicopathological parameters were evaluated. Finally, its functions and potential mechanisms were investigated through a series gain- and loss-of-function strategies both in vitro and in vivo.

RESULTS

TRIP13 was significantly overexpressed in HCC tissues and high level of TRIP13 was closely correlated with a worse clinical outcome. Functionally, elevated TRIP13 facilitated cell proliferation, migration, invasion, and promoted cellular epithelial-mesenchymal transition (EMT) in vitro, while promote tumor growth and lung metastasis in vivo. Mechanistically, TRIP13 interacted with ACTN4 and positively regulated its expression, thus activating the AKT/mTOR pathway to drive tumor progression. Moreover, miR-192-5p served as an upstream regulator of TRIP13 by directly binding to TRIP13 mRNA 3' UTR, which may partially explain the high expression of TRIP13 in HCC.

CONCLUSION

Our findings identified TRIP13 as a promising candidate oncogene in HCC, and TRIP13 induced cell migration, invasion and metastasis of HCC through the AKT/mTOR signaling via interacting with ACTN4.

Targeting Mechanoresponsive Proteins in Pancreatic Cancer: 4-Hydroxyacetophenone Blocks Dissemination and Invasion by Activating MYH14

Metastasis is complex, involving multiple genetic, epigenetic, biochemical, and physical changes in the cancer cell and its microenvironment. Cells with metastatic potential are often characterized by altered cellular contractility and deformability, lending them the flexibility to disseminate and navigate through different microenvironments. We demonstrate that mechanoresponsiveness is a hallmark of pancreatic cancer cells. Key mechanoresponsive proteins, those that accumulate in response to mechanical stress, specifically nonmuscle myosin IIA (MYH9) and IIC (MYH14), α-actinin 4, and filamin B, were highly expressed in pancreatic cancer as compared with healthy ductal epithelia. Their less responsive sister paralogs-myosin IIB (MYH10), α-actinin 1, and filamin A-had lower expression differential or disappeared with cancer progression. We demonstrate that proteins whose cellular contributions are often overlooked because of their low abundance can have profound impact on cell architecture, behavior, and mechanics. Here, the low abundant protein MYH14 promoted metastatic behavior and could be exploited with 4-hydroxyacetophenone (4-HAP), which increased MYH14 assembly, stiffening cells. As a result, 4-HAP decreased dissemination, induced cortical actin belts in spheroids, and slowed retrograde actin flow. 4-HAP also reduced liver metastases in human pancreatic cancer-bearing nude mice. Thus, increasing MYH14 assembly overwhelms the ability of cells to polarize and invade, suggesting targeting the mechanoresponsive proteins of the actin cytoskeleton as a new strategy to improve the survival of patients with pancreatic cancer. SIGNIFICANCE: This study demonstrates that mechanoresponsive proteins become upregulated with pancreatic cancer progression and that this system of proteins can be pharmacologically targeted to inhibit the metastatic potential of pancreatic cancer cells.

Long Noncoding RNA SChLAP1 Forms a Growth-Promoting Complex with HNRNPL in Human Glioblastoma through Stabilization of ACTN4 and Activation of NF-κB Signaling

PURPOSE

Long noncoding RNAs (lncRNA) have essential roles in diverse cellular processes, both in normal and diseased cell types, and thus have emerged as potential therapeutic targets. A specific member of this family, the SWI/SNF complex antagonist associated with prostate cancer 1 (SChLAP1), has been shown to promote aggressive prostate cancer growth by antagonizing the SWI/SNF complex and therefore serves as a biomarker for poor prognosis. Here, we investigated whether SChLAP1 plays a potential role in the development of human glioblastoma (GBM).

EXPERIMENTAL DESIGN

RNA-ISH and IHC were performed on a tissue microarray to assess expression of SChLAP1 and associated proteins in human gliomas. Proteins complexed with SChLAP1 were identified using RNA pull-down and mass spectrometry. Lentiviral constructs were used for functional analysis in vitro and in vivo.

RESULTS

SChLAP1 was increased in primary GBM samples and cell lines, and knockdown of the lncRNA suppressed growth. SChLAP1 was found to bind heterogeneous nuclear ribonucleoprotein L (HNRNPL), which stabilized the lncRNA and led to an enhanced interaction with the protein actinin alpha 4 (ACTN4). ACTN4 was also highly expressed in primary GBM samples and was associated with poorer overall survival in glioma patients. The SChLAP1-HNRNPL complex led to stabilization of ACTN4 through suppression of proteasomal degradation, which resulted in increased nuclear localization of the p65 subunit of NF-κB and activation of NF-κB signaling, a pathway associated with cancer development.

CONCLUSIONS

Our results implicated SChLAP1 as a driver of GBM growth as well as a potential therapeutic target in treatment of the disease.

ACTN4 Promotes the Proliferation, Migration, Metastasis of Osteosarcoma and Enhances its Invasive Ability through the NF-κB Pathway

Alpha-actinin-4 (ACTN4) is associated with different types of tumors, but its role in osteosarcoma (OS) is not known. We aimed to investigate the effect of ACTN4 on the growth, migration, invasion and metastasis of OS. We further explored the possible mechanism of how ACTN4 affects the development of OS. First, the expression of ACTN4 in OS tissues and OS cell lines was analyzed by PCR. Second, the role of ACTN4 in the development of OS was explored by the proliferation, scratch, and invasion assays. We further explored the effect of ACTN4 on OS growth in an orthotopic xenograft model of nude mice. In addition, we used hematoxylin and eosin (HE) staining of lung tissues in nude mice to observe the effect of ACTN4 on lung metastasis of OS. Finally, rescue experiments further investigated the role of NF-κB on ACTN4 in the development of OS. ACTN4 was highly expressed in OS tissues and OS cell lines. In vitro experiments demonstrated that reducing ACTN4 expression inhibited the proliferation, migration, and invasion of OS. In contrast, overexpression of ACTN4 promotes these effects. In vivo experiments further validated that ACTN4 promoted the growth of OS. The HE staining of lungs in nude mice revealed that ACTN4 promoted lung metastasis of OS. In addition, we found that ACTN4 enhanced the ability of OS to invade, through the NF-κB pathway. ACTN4 promotes the proliferation, migration, metastasis of OS and enhances its invasion ability through the NF-κB pathway.

Proteomic Differences in Feline Fibrosarcomas Grown Using Doxorubicin-Sensitive and -Resistant Cell Lines in the Chick Embryo Model

Proteomic analyses are rapid and powerful tools that are used to increase the understanding of cancer pathogenesis, discover cancer biomarkers and predictive markers, and select and monitor novel targets for cancer therapy. Feline injection-site sarcomas (FISS) are aggressive skin tumours with high recurrence rates, despite treatment with surgery, radiotherapy, and chemotherapy. Doxorubicin is a drug of choice for soft tissue sarcomas, including FISS. However, multidrug resistance is one of the major causes of chemotherapy failure. The main aim of the present study was to identify proteins that differentiate doxorubicin-resistant from doxorubicin-sensitive FISS using two-dimensional gel electrophoresis (2DE), followed by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) analysis. Using the three-dimensional (3D) preclinical in ovo model, which resembles features of spontaneous fibrosarcomas, three significantly (p ≤ 0.05) differentially expressed proteins were identified in tumours grown from doxorubicin-resistant fibrosarcoma cell lines (FFS1 and FFS3) in comparison to the doxorubicin-sensitive one (FFS5): Annexin A5 (ANXA5), Annexin A3 (ANXA3), and meiosis-specific nuclear structural protein 1 (MNS1). Moreover, nine other proteins were significantly differentially expressed in tumours grown from the high doxorubicin-resistant cell line (FFS1) in comparison to sensitive one (FFS5). This study may be the first proteomic fingerprinting of FISS reported, identifying potential candidates for specific predictive biomarkers and research targets for doxorubicin-resistant FISS.