Cdc42 expression in cervical cancer and its effects on cervical tumor invasion and migration

Serum cell division cycle 42 in advanced hepatocellular carcinoma patients: Linkage with clinical characteristics and immune checkpoint inhibitor-related treatment outcomes

OBJECTIVE

Cell division cycle 42 (CDC42) facilitates immune escape and drug resistance towards immunotherapy in several malignancies. This prospective study aimed to explore the predictive value of serum CDC42 for immune checkpoint inhibitor (ICI)-treatment response and survival in advanced hepatocellular carcinoma (HCC) patients.

METHODS

Thirty advanced HCC patients scheduled for ICI or ICI-based treatment were enrolled in this prospective study, whose serum CDC42 was determined via enzyme-linked immunosorbent assay before therapy initiation.

RESULTS

The median (interquartile range) of serum CDC42 level was 766.5 (605.0-1329.5) pg/mL. Serum CDC42 was related to increased tumor size but decreased programmed death-ligand 1 combined positive score (PD-L1 CPS). With respect to ICI or ICI-based treatment outcomes, elevated serum CDC42 was associated with decreased disease control rate, but did not link with objective response rate. Patients with high serum CDC42 (vs. low, cut by its median level) had shortened progression-free survival (PFS), while overall survival (OS) only disclosed a reduced trend (lacked statistical significance) in patients with high serum CDC42 (vs. low). In detail, the median (95%CI) PFS and OS were 3.0 (0.0-6.0) months and 11.7 (2.7-20.7) months in patients with high serum CDC42, while they were 11.1 (6.6-15.6) months and 19.3 (14.5-24.1) months in patients with low CDC42. After adjusted by multivariate cox regression analysis, high serum CDC42 (vs. low) was independently associated with shortened PFS, but not OS.

CONCLUSIONS

Elevated serum CDC42 possesses a potential value in predicting worse ICI or ICI-based treatment outcomes in advanced HCC.

"From molecular to clinic": The pivotal role of CDC42 in pathophysiology of human papilloma virus related cancers and a correlated sensitivity of afatinib

Background

Human papilloma virus (HPV)-related cancers are global health challenge. Insufficient comprehension of these cancers has impeded the development of novel therapeutic interventions. Bioinformatics empowered us to investigate these cancers from new entry points.

Methods

DNA methylation data of cervical squamous cell carcinoma (CESC) and anal squamous cell carcinoma (ASCC) were analyzed to identify the significantly altered pathways. Through analyses integrated with RNA sequencing data of genes in these pathways, genes with strongest correlation to the TNM staging of CESC was identified and their correlations with overall survival in patients were assessed. To find a potential promising drug, correlation analysis of gene expression levels and compound sensitivity was performed. In vitro experiments were conducted to validate these findings. We further performed molecular docking experiments to explain our findings.

Results

Significantly altered pathways included immune, HPV infection, oxidative stress, ferroptosis and necroptosis. 10 hub genes in these pathways (PSMD11, RB1, SAE1, TAF15, TFDP1, CORO1C, JOSD1, CDC42, KPNA2 and NUP62) were identified, in which only CDC42 high expression was statistically significantly correlated with overall survival (Hazard Ratio: 1.6, P = 0.045). Afatinib was then screened out to be tested. In vitro experiments exhibited that the expression level of CDC42 was upregulated in HaCaT/A431 cells transfected with HPV E6 and E7, and the inhibitory effect of afatinib on proliferation was enhanced after transfection. CDC42-GTPase-effector interface-EGFR-afatinib was found to be a stable complex with a highest ZDOCK score of 1264.017.

Conclusion

We identified CDC42 as a pivotal gene in the pathophysiology of HPV-related cancers. The upregulation of CDC42 could be a signal for afatinib treatment and the mechanism in which may be an increased affinity of EGFR to afatinib, inferred from a high stability in the quaternary complex of CDC42-GTPase-effector interface-EGFR-afatinib.

Dermcidin Enhances the Migration, Invasion, and Metastasis of Hepatocellular Carcinoma Cells In Vitro and In Vivo

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is a common primary liver neoplasm with high mortality. Dermcidin (DCD), an antimicrobial peptide, has been reported to participate in oncogenesis. This study assessed the effects and underlying molecular events of DCD overexpression and knockdown on the regulation of HCC progression in vitro and in vivo.

METHODS

The serum DCD level was detected using enzyme-linked immunosorbent assay. DCD overexpression, knockdown, and Ras-related C3 botulinum toxin substrate 1 (Rac1) rescue were performed in SK-HEP-1 cells using plasmids. Immunofluorescence staining, quantitative PCR, and Western blotting were used to detect the expression of different genes and proteins. Differences in HCC cell migration and invasion were detected by Transwell migration and invasion assays. A nude mouse HCC cell orthotopic model was employed to verify the in vitro data.

RESULTS

The level of serum DCD was higher in patients with HCC and in SK-HEP-1 cells. DCD overexpression caused upregulation of DCD, fibronectin, Rac1, and cell division control protein 42 homologue (Cdc42) mRNA and proteins as well as actin-related protein 2/3 (Arp2/3) protein (but reduced Arp2/3 mRNA levels) and activated Rac1 and Cdc42. Phenotypically, DCD overexpression induced HCC cell migration and invasion in vitro, whereas knockout of DCD expression had the opposite effects. A Rac1 rescue experiment in DCD-knockdown HCC cells increased HCC cell migration and invasion and increased the levels of active Rac1/total Rac1, Wiskott-Aldrich syndrome family protein (WASP), Arp2/3, and fibronectin. DCD overexpression induced HCC cell metastasis to the abdomen and liver in vivo.

CONCLUSIONS

DCD promotes HCC cell migration, invasion, and metastasis through upregulation of noncatalytic region of tyrosine kinase adaptor protein 1 (Nck1), Rac1, Cdc42, WASP, and Arp2/3, which induce actin cytoskeletal remodeling and fibronectin-mediated cell adhesion in HCC cells.

N2E4, a Monoclonal Antibody Targeting Neuropilin-2, Inhibits Tumor Growth and Metastasis in Pancreatic Ductal Adenocarcinoma via Suppressing FAK/Erk/HIF-1α Signaling

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with extremely limited treatment; the effective targeting strategy stays an urgent unmet need. Neuropilin-2 (NRP2), a multifunctional transmembrane non-tyrosine-kinase glycoprotein, enhances various signal transduction pathways to modulate cancer progression. However, the application value of NRP2 as a therapeutic target in pancreatic cancer is still unclear. Here, we detected the elevated NRP2 was associated with the poor prognosis of pancreas carcinoma. The mouse monoclonal antibody targeting NRP2 (N2E4) that could specifically bind to PDAC cells was developed. Moreover, N2E4 inhibits PDAC proliferation, migration, and invasion in vitro, and repressed growth and metastasis in vivo. Mechanistically, the effect of N2E4 was mainly related to the blocking of interaction between NRP2 with integrinβ1 to inhibit FAK/Erk/HIF-1a/VEGF signaling. Therefore, N2E4 has the potential for targeting therapy of PDAC. This study lays a foundation for the future development of NRP2-based targeted therapy for PDAC.

The roles of Cdc42 and Rac1 in the formation of plasma membrane protrusions in cancer epithelial HeLa cells

The inducible model of clones generated from the cervical cancer epithelial HeLa cell line has shown the role of DOCK10 as a guanine-nucleotide exchange factor for Rho GTPases Cdc42 and Rac1 and as an inducer of filopodia and plasma membrane (PM) ruffles. In this model, constitutively active (CA) mutants of Cdc42 and Rac1 promote filopodia and ruffles, respectively, as in other models. DOCK9 also induces filopodia and ruffles, although ruffling activity is less prominent. By exploiting this model further, the aim of this work is to provide a more complete understanding of the role of Cdc42 and Rac1, and their interactions with DOCK10 and DOCK9, in regulation of PM protrusions. New clones have been generated from HeLa, including single clones expressing one form of wild-type (WT) or dominant negative (DN) Cdc42 or Rac1, and double clones co-expressing one of them together with either DOCK10 or DOCK9. Expression of WT- and DN-Cdc42 induced filopodia. WT-Cdc42 and, especially, DN-Cdc42 also gave rise to veil protrusions, which were neutralized by DOCK10. Moreover, DN-Cdc42 stimulated the emergence of ruffles, further increased by DOCK10, and WT-Cdc42 also augmented ruffles in presence of DOCK9 and DOCK10. WT-Rac1 greatly increased PM blebbing, as did DN-Rac1 more moderately. In both cases, blebs were enhanced by DOCK10. DN-Rac1 and CA-Rac1 moderately raised filopodia, and DOCK10 and DOCK9 had opposed effects on filopodia (up and down, respectively) in presence of WT-Rac1. As conclusions, we highlight that Cdc42 promotes filopodia regardless of its conformational state, and Rac1 induces blebs in conformations other than CA, especially WT-Rac1, in the inducible HeLa clones. The model could be useful to learn more about the mechanisms underlying PM protrusions.

MiR-29a inhibits cell proliferation and migration by targeting the CDC42/PAK1 signaling pathway in cervical cancer

Cervical cancer is the second most common gynecological malignancy worldwide and the tumorigenesis mechanisms of cervical cancer are still unclear. This study aimed to reveal the role of miR-29a in cervical cancer. The expression level of miR-29a and CDC42 was measured using qRT-PCR. Cell proliferation, apoptosis, migration, and invasion were detected using colony formation, flow cytometry analysis, wound-healing assay, and Transwell assay, respectively. Luciferase reporter assay was used to determine the binding of miR-29a with CDC42. CDC42/p21-activated kinase 1 (PAK1) pathway-related proteins were measured by western blotting. MiR-29a was downregulated and CDC42 was upregulated in cervical cancer cells. Luciferase reporter assay showed that miR-29a negatively regulated the expression of CDC42 by directly targeting 3'-UTR of CDC42. Cell proliferation, migration, and invasion were markedly inhibited, whereas cell apoptosis was significantly increased in Hela and CaSki cells transfected with miR-29a mimics. These effects were partly recovered by CDC42 overexpression. Protein levels of PAK1, p-PAK1, p-LIMK, and p-cofilin were significantly downregulated by miR-29a mimics, which was reversed by CDC42 overexpression and was increased by the miR-29a inhibitor. MiR-29a inhibited cell proliferation, migration, and invasion, as well as promoted cell apoptosis through repressing the PAK1/LIMK signaling pathway by targeting CDC42 in cervical cancer.

TOP2A Promotes Cell Migration, Invasion and Epithelial-Mesenchymal Transition in Cervical Cancer via Activating the PI3K/AKT Signaling

Background/Objective

Topoisomerases type IIA (TOP2A) was identified to present with a high-expression pattern in cervical cancer. However, TOP2A role in the progression of cervical cancer remains unknown. Here, we aimed to explore the effect and reveal the underlying mechanism of TOP2A in the migration, invasion and epithelial–mesenchymal transition (EMT) of cervical cancer.

Materials and Methods

The expression profiles of TOP2A in 20 paired cervical cancer tissues and the paracancerous normal tissues were detected by using Western blotting assay. Transwell chambers were used to test cell migration and invasion abilities. Cell morphology and the expressions of E-cadherin and N-cadherin were detected to assess cell EMT. LY294002 was used to inhibit the activation of PI3K/AKT signaling.

Results

Compared with the paracancerous normal tissues, TOP2A was overexpressed in 85% (17/20) cervical cancer tissues. Repression of TOP2A expression in SiHa cells significantly weakened cell migration and invasion abilities, reduced cell numbers in shuttle shape and increased E-cadherin expression while decreased E-cadherin expression. To the opposite, overexpression of TOP2A in Hela cells induced opposite results. In addition, the expression of p-AKT was increased when TOP2A was overexpressed in Hela cells, and p-AKT expression was decreased when TOP2A was silenced in SiHa cells. Moreover, suppression of the PI3K/AKT signaling with LY294002 treatment apparently rescued TOP2A-mediated promotions in cell migration, invasion and EMT in Hela cells.

Conclusion

This study reveals that TOP2A is abnormally overexpressed in cervical cancer tissues, and TOP2A overexpression leads to cell migration, invasion and EMT via activating PI3K/AKT signaling.

Downregulation of miR-224-5p Promotes Migration and Proliferation in Human Dental Pulp Stem Cells

Introduction

Pulp regeneration, as a treatment for pulp necrosis, has significant advantages over root canal therapy for the preservation of living pulp. To date, research on pulp regeneration has mainly focused on the transplantation of pulp stem cells into the root canal, but there is still a lack of research on the migration of pulp cells into the root canal via cell homing. Stem cells from the apical tooth papilla (SCAP) are recognized as multidirectional stem cells, but these cells are difficult to obtain. MicroRNAs are small noncoding RNAs that play crucial roles in regulating normal and pathologic functions. We hypothesized that some types of microRNAs might improve the migration and proliferation function of dental pulp stem cells (DPSCs), which are easily obtained in clinical practice, and as a result, DPSCs might replace SCAP and provide valuable information for regenerative endodontics.

Methods

Magnetic activated cell sorting of DPSCs and SCAP was performed. Next-generation sequencing was performed to examine DPSCs and SCAP miRNAs expression and to identify the most significant differentially expressed miRNA. CCK-8 and transwell assays were used to determine the impact of this miRNA on DPSCs proliferation and migration.

Results

The most significant differentially expressed miRNA between DPSCs and SCAP was miR-224-5p. Downregulating miR-224-5p promoted DPSCs proliferation and migration; the opposite results were observed when miR-224-5p was upregulated.

Conclusion

MiR-224-5p promotes proliferation and migration in DPSCs, a finding that is of great significance for further exploring the role of dental pulp stem cells in regenerative endodontics.

Restoration of microRNA-29c in type I endometrioid cancer reduced endometrial cancer cell growth

Endometrial cancer is the most common gynaecological cancer worldwide, and the prognosis of patients with advanced disease remains poor. MicroRNAs (miRs) are dysregulated in endometrial cancer. miRs-29-a, -b and -c expression levels are downregulated in endometrial cancer; however, a specific role for miR-29c and its target genes remain to be elucidated. The aim of the present study was to determine the functional effect of restoring miR-29c expression in endometrial cancer cell lines and to identify miR-29c targets involved in cancer progression. miR-29c expression in human endometrial tumour grades 1-3 and benign tissue as well as in the endometrial cancer cell lines Ishikawa, HEC1A and AN3CA were analysed using reverse transcriptase-quantitative PCR (RT-qPCR). The cell lines were transfected with miR-29c mimic, miR-29c inhibitor or scrambled control. xCELLigence real-time cell monitoring analysed proliferation and migration, and flow cytometry was used to analyse apoptosis and cell cycle. The expression of miR-29c target genes in transfected cell lines was analysed using RT-qPCR. miR-29c was downregulated in grade 1-3 endometrial cancer samples compared with benign endometrium. miR-29c was reduced in Ishikawa and AN3CA cells, but not in HEC1A cell lines compared with non-cancerous primary human endometrial epithelial cells. Overexpression of miR-29c variably reduced proliferation, increased apoptosis and reduced the expression levels of miR-29c target genes, including cell division cycle 42, HMG-box transcription factor 1, integrin subunit β 1, MCL1 apoptosis regulator BCL2 family member, MDM2 proto-oncogene, serum/glucocorticoid regulated kinase 1, sirtuin 1 and vascular endothelial growth factor A, across the three cell lines investigated. Inhibition of miR-29c in HEC1A cells increased proliferation and collagen type IV α 1 chain expression. The re-introduction of miR-29c to endometrial cancer cell lines reduced proliferation, increased apoptosis and reduced miR-29c target gene expression in vitro. The present results suggested that miR-29c may be a potential therapeutic target for endometrial cancer.

S100A9 promotes the proliferation and migration of cervical cancer cells by inducing epithelial‑mesenchymal transition and activating the Wnt/β‑catenin pathway

S100 calcium-binding protein A9 (S100A9), a member of the S100 protein family, is often upregulated in various cancers, including cervical cancer. Elevated S100A9 expression is thought to serve an important role in tumorigenesis; however, the exact role of S100A9 in the modulation of cervical cancer and the underlying molecular mechanism remain unknown. In the present study, we aimed to investigate the effects of S100A9 on the proliferation and migration of cervical cancer cells, as well as the molecular mechanisms underlying these effects. Our results demonstrated that endogenous expression of S100A9 in SiHa and CaSki cell lines was significantly higher than in the HeLa cell line. As expected, overexpression of S100A9 enhanced the proliferation and migration of cervical cancer cells. In addition, S100A9 overexpression induced epithelial-mesenchymal transition (EMT) as determined by reduced expression levels of the epithelial marker E-cadherin, whereas the expression levels of the mesenchymal marker vimentin were upregulated. Furthermore, it was reported that the effects of S100A9 in the modulation of cervical cancer cells were mediated through the Wnt/β-catenin signaling pathway as β-catenin knockdown significantly suppressed the ability of S100A9 to enhance the proliferation and migration of cervical cancer cells. Collectively, these findings suggest that S100A9 promoted the proliferation and migration of cervical cancer cell lines. Furthermore, the underlying molecular mechanisms may be partially attributed to the induction of EMT and activation of the Wnt/β-catenin signaling pathway.

In silico identification of key genes and signaling pathways targeted by a panel of signature microRNAs in prostate cancer

Accumulating evidence have suggested that some microRNAs are aberrantly expressed in prostate cancer. In our previous work, we had identified a panel of four differentially expressed microRNAs in prostate cancer. In the present study, we have investigated common molecular targets of this panel of miRNAs (DEMs) and key hub genes that can serve as potential candidate biomarkers in the pathogenesis and progression of prostate cancer. A joint bioinformatics approach was employed to identify differentially expressed genes (DEGs) in prostate cancer. Gene enrichment analysis followed by the protein-protein interaction (PPI) network construction and selection of hub genes was further performed using String and Cytoscape, respectively. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the identified hub genes was conducted using the Database for Annotation, Visualization and Integrated Discovery (DAVID) tool. In total, 496 genes were identified to be common targets of DEMs in prostate cancer and 13 key hub genes were identified from three modules of the PPI network of the DEGs. Further top five genes viz Rhoa, PI3KCA, CDC42, MAPK3, TP53 were used for Enrichment analysis which revealed their association with vital cellular and functional pathways in prostate cancer indicating their potential as candidate biomarkers in prostate cancer.

Mir20a/106a-WTX axis regulates RhoGDIa/CDC42 signaling and colon cancer progression

Wilms tumor gene on the X chromosome (WTX) is a putative tumor suppressor gene in Wilms tumor, but its expression and functions in other tumors are unclear. Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in women and the second leading cause in men in the United States. We demonstrated that WTX frequently lost in CRC which was highly correlated with cell proliferation, tumor invasion and metastasis. Mechanistically, WTX loss disrupts the interaction between RhoGDIα and CDC42 by losing of the binding with RhoGDIα and triggers the activation of CDC42 and its downstream cascades, which promotes CRC development and liver metastasis. The aberrant upregulation of miR-20a/miR-106a were identified as the reason of WTX loss in CRC both in vivo and in vitro. These study defined the mechanism how miR-20a/miR-106a-mediated WTX loss regulates CRC progression and metastasis, and provided a potential therapeutic target for preventing CRC progression.

Investigation of the therapy targets of Yi-Qi-Yang-Yin-Hua-Tan-Qu-Yu recipe on type 2 diabetes by serum proteome labeled with iTRAQ

ETHNOPHARMACOLOGY RELEVANCE

Based on basic theories of Chinese medicine, Yi-Qi-Yang-Yin-Hua-Tan-Qu-Yu (YQYYHTQY) recipe was constituted by eleven kinds of Chinese herbs and effective in treatment of type 2 diabetes (T2DM). But the therapy target was unclear.

OBJECTIVE

In this study, we used the serum proteome labeled by iTRAQ to find therapy target of YQYYHTQY recipe on T2DM.

MATERIALS AND METHODS

The rat model was induced by high-fat diet (HFD) and streptozotocin (STZ, 30 mg/kg). Drugs were administered to rats once daily for 14 days. Related laboratory parameters were observed. Serum proteome were compared between T2DM and YQYYHTQY group using the iTRAQ labeling quantitative proteomics technique. Functional differential proteins were analysis by STRING software. Target proteins were confirmed by ELISA kits.

RESULTS

Hyperglycemia, hyperinsulinemia, insulin resistance, decrease of glucose transporter, depilation, less activity, flock together, depression, ecchymosis of tongue and tail appearance, the typical diabetic patients "a little more than three" symptoms, as well as the decrease of grip strength, serum cyclic adenosine monophosphate (cAMP)/ cyclic guanosine monophosphate (cGMP) ratio, serum high density lipoprotein-cholesterol (HDL-C) and the increase of serum triglyceride (TG), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), thromboxane B₂ (TXB₂)/ 6-keto prostaglandin F1α (6-keto PGF1α) ratio, endothelin-1 (ET-1) levels were found in T2DM group. After drugs treatment, all the above indexes almost were improved in different degrees and effect of YQYYHTQY recipe was superior to pioglitazone hydrochloride. In addition, there were 23 differential proteins, 5 up-regulated and 18 down-regulated proteins. Of them, there were 4 proteins related with diabetes, blood and behavior. Cell division control protein 42 homolog (CDC42) and Ras homolog gene family member A (RhoA) were the therapy targets of YQYYHTQY recipe on T2DM.

CONCLUSIONS

YQYYHTQY recipe showed therapy effect on T2DM. CDC42 and RhoA proteins were the therapy targets of YQYYHTQY recipe.

Upregulated expression of HOXC8 is associated with poor prognosis of cervical cancer

Homeobox C8 (HOXC8) is a transcription factor that has been reported to regulate numerous genes associated with tumor progression. However, its function in cervical cancer (CC) remains to be elucidated. In the present study, the expression level of HOXC8 was examined in CC tissues and cell lines using reverse transcription-quantitative polymerase chain reaction and western blot analysis. Additionally, CC cell lines were transfected with small interfering RNAs (siRNAs) to downregulate the expression of HOX8 and assess cell proliferation using Cell Counting Kit-8. The results demonstrated a significantly increased expression of HOXC8 in CC tissues and cell lines compared with non-tumor tissues, and a normal cervical cell line, respectively. Additionally, the downregulation of HOXC8, which was achieved by siRNA transfection, significantly inhibited the proliferation rate of CC cell lines. Kaplan-Meier curves demonstrated that the increased expression of HOXC8 was associated with poor prognosis of patients with CC. Additionally, univariate and multivariate analysis revealed that HOXC8 was a significant and independent predictor for overall survival of patients with CC. In conclusion, the results of the present study suggest that HOXC8 may be involved in the progression of CC and may serve as a therapeutic target for CC.

Aberrant methylation-mediated silencing of microRNAs contributes to HPV-induced anchorage independence

Cervical cancer and a subset of anogenital and head-and-neck carcinomas are caused by high-risk types of the human papillomavirus (hrHPV). During hrHPV-induced malignant transformation keratinocytes become able to grow anchorage independently, a tumorigenic trait at least partly associated with inactivation of tumor suppressor genes. We used hrHPV-containing keratinocytes to investigate the role of DNA methylation-mediated silencing of microRNAs (miRNAs) in the acquisition of anchorage independence.

Anchorage dependent (n=11) and independent passages (n=19) of 4 hrHPV-immortalized keratinocyte cell lines were treated with 2′-deoxy-5-azacytidine (DAC). Genome-wide miRNA expression profiles before and after treatment were compared to identify miRNAs silenced by methylation. Bisulfite sequencing and methylation-specific PCR showed increased methylation of hsa-mir-129-2/-137/-935/-3663/-3665 and -4281 in anchorage independent HPV-transformed keratinocytes and cervical cancer cell lines. Mature miRNAs derived from hsa-mir-129-2/-137/-3663 and -3665 showed functional relevance as they decreased anchorage independence in cervical cancer cell lines. Cervical (pre)cancerous lesions demonstrated increased methylation of hsa-mir-129-2/-935/-3663/-3665 and -4281, underlining the clinical relevance of our findings.

In conclusion, methylation-mediated silencing of tumor suppressive miRNAs contributes to acquisition of an anchorage independent phenotype. This study further substantiates the importance of miRNAs during early stages of carcinogenesis and underlines their potential as both disease markers and therapeutic targets.

The Role of Actin Dynamics and Actin-Binding Proteins Expression in Epithelial-to-Mesenchymal Transition and Its Association with Cancer Progression and Evaluation of Possible Therapeutic Targets

Metastasis causes death of 90% of cancer patients, so it is the most significant issue associated with cancer disease. Thus, it is no surprise that many researchers are trying to develop drugs targeting or preventing them. The secondary tumour site formation is closely related to phenomena like epithelial-to-mesenchymal and its reverse, mesenchymal-to-epithelial transition. The change of the cells' phenotype to mesenchymal involves the acquisition of migratory potential. Cancer cells movement is possible due to the development of invasive structures like invadopodia, lamellipodia, and filopodia. These changes are dependent on the reorganization of the actin cytoskeleton. In turn, the polymerization and depolymerization of actin are controlled by actin-binding proteins. In many tumour cells, the actin and actin-associated proteins are accumulated in the cell nucleus, suggesting that it may also affect the progression of cancer by regulating gene expression. Once the cancer cell reaches a new habitat it again acquires epithelial features and thus proliferative activity. Targeting of epithelial-to-mesenchymal or/and mesenchymal-to-epithelial transitions through regulation of their main components expression may be a potential solution to the problem of metastasis. This work focuses on the role of these processes in tumour progression and the assessment of therapeutic potential of agents targeting them.

Total alkaloids of Corydalis saxicola bunting inhibits migration of A549 cells by suppressing Cdc42 or Vav1

Cell division cycle 42 (Cdc42) is a critical regulator, which functions in cancer metastasis. Numerous previous studies have demonstrated that vav guanine nucleotide exchange factor 1 (Vav1) is ectopically expressed in numerous types of human malignancies and have suggested that Vav1 may efficiently promote the formation of invadopodia and matrix degradation by regulating the activation of Cdc42. Total alkaloids of Corydalis saxicola bunting (TAOCSB), a type of alkaloid compound extracted from the root of C. saxicola bunting, has been revealed to have anticancer properties. However, there is no available information to address the effects of TAOCSB on the metastasis of human lung cancer. In the present study, the anticancer effect on A549 non-small cell lung cancer cells induced by TAOCSB was investigated, as well as its underlying mechanisms. The results demonstrated that a low dose of TAOCSB exhibited anti-metastatic potential in suppressing the invasion and migration of A549 cells, and this action may be involved in TAOCSB-mediated inhibition of Cdc42 expression at the level of mRNA and protein in parallel with TAOCSB-mediated inhibition of matrix metalloproteinase (MMP)-2 and MMP-9 protein expression levels. Although the present study did not reveal the expression level of Vav1 protein in A549 cells, the expression level of Vav1 mRNA was investigated. The effect of Vav1 expression in A549 cells requires further study. Overall, the results of the present study revealed that TAOCSB may provide more information regarding lung cancer treatment.

Nanomechanical Characteristics of Cervical Cancer and Cervical Intraepithelial Neoplasia Revealed by Atomic Force Microscopy

Background

Understanding the biological features and developmental progress of cervical cancer is crucial for disease prevention. This study aimed to determine the nanomechanical signatures of cervical samples, ranging from cervicitis to cervical carcinomas, and to investigate the underlying mechanisms.

Material/Methods

Forty-five cervical biopsies at various pathological stages were subjected to atomic force microscopy (AFM) measurements. Cdc42 and collagen I were quantified using immunohistochemical staining to investigate their relationship with nanomechanical properties of cervical cancers and premalignant lesions.

Results

We found that the lower elasticity peaks (LEPs) in the high-grade squamous intraepithelial lesion (HSIL) group (21.24±3.83 kPa) and higher elasticity peaks (HEPs) in the cancer group (81.23±8.82 kPa) were upshifted compared with the control group (LEP at 8.51±0.18 kPa and HEP at 44.07±3.54 kPa). Furthermore, compared with the control [29.51±13.61 for cell division cycle 42 (Cdc42) expression and 28.61±17.65 for collagen I expression], immunohistochemical staining verified a significant increase of Cdc42 in the HSIL group (50.57±23.85) and collagen I (56.09±25.70) in the cancer group. In addition, using the Pearson correlation coefficient, Cdc42 expression tended to be positively correlated with LEP locations (r=0.63, P=0.012), while collagen I expression displayed a strong and positive correlation with HEP positions (r=0.88, P<0.001).

Conclusions

The nanomechanical properties of HSIL and cancer biopsies show unique features compared with controls, and these alterations are probably due to changes in cytoskeleton and extracellular matrix contents.

High Expression of Cell Division Cycle 42 Promotes Pancreatic Cancer Growth and Predicts Poor Outcome of Pancreatic Cancer Patients

BACKGROUND

Cell division cycle 42 (CDC42), an important member of the Rho family, is overexpressed in various human cancers. However, its expression and role in pancreatic cancer (PC) are not well understood.

AIM

The present study was designed to investigate the expression patterns and underlying cellular mechanisms of CDC42 in PC.

METHODS

First, immunohistochemical analysis, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were performed to detect CDC42 expression in clinical pancreatic carcinoma and adjacent tissues. Second, differential expression of CDC42 between PC cells and normal cells was evaluated by qRT-PCR and Western blotting. Third, the correlation between CDC42 expression as well as clinicopathological characteristics and patient survival was analyzed. Finally, CDC42 was knocked down to examine its role both in vivo and in vitro.

RESULTS

The results showed significantly increased CDC42 expression in pancreatic tumor tissues compared with adjacent normal tissues, as revealed by qRT-PCR, Western blotting and immunostaining. Compared to PanC-1 cells, CDC42 expression was downregulated in HPDE6-C7 cells as shown by qRT-PCR and Western blotting. High CDC42 expression was observed in 69.2% (83/120) of pancreatic adenocarcinoma patients and was significantly associated with tumor differentiation (p = 0.013), median tumor size (p = 0.005), tumor infiltration (pT stage, p = 0.04), lymph nodal status (pN stage, p = 0.044) and TNM staging (p = 0.003). Multivariate Cox regression analysis revealed CDC42 expression to be an independent predictor of survival of PC patients (HR 3.0, 95% CI 1.60-5.61, p = 0.001). Finally, we found that CDC42 promoted the proliferation of PanC-1 cells both in vivo and in vitro.

CONCLUSIONS

Our findings reveal that CDC42 might play an important role in promoting PC development, and the findings suggest that CDC42 might serve as a potential prognostic indicator of PC.

srGAP1 mediates the migration inhibition effect of Slit2-Robo1 in colorectal cancer

BACKGROUND

The neuronal guidance molecule Slit2 plays suppressive role in tumorigenesis and progression. We previously showed that Slit2-Robo1 inhibit cell migration in colorectal cancer (CRC). However, little is known about its downstream effectors in CRC. This study tries to identify whether the Slit-Robo Rho GTPase activating protein 1 (srGAP1) could mediate the inhibitory effect of Slit2-Robo1 on CRC cell migration.

METHODS

The protein expression of srGAP1 in clinical CRC tissues was tested by immunohistochemistry staining. Conditioned medium was prepared from HEK293 cells stably expressing Slit2-myc, Robo1-HA or RoboN (a soluble extracellular domain of Robo1). Immunoprecipitation (IP) was applied to check the interaction between Robo1 and srGAP1, and immunofluorescence (IF) was used to observe the subcellular localization of Robo1 and srGAP1. Small GTPase pull-down assay was used to determine the activity of Cdc42. A modified wound healing assay was performed to detect cell migration.

RESULTS

The protein expression of srGAP1 was remarkably decreased in 47.5% of CRC tissues compared with adjacent noncancerous tissues, and the decreased srGAP1 expression was associated with lymphatic invasion, poor tumor differentiation, high TNM stage, and poor survival (P < 0.05). IP and IF assays revealed that srGAP1 was a Robo1-interacting protein and exhibited similar dynamic subcellular distribution after Slit2 treatment in CRC cells. Small GTPase pull-down assay and migration assay indicated that Slit2-Robo1 signaling inhibited Cdc42 activity and CRC cell motility through srGAP1.

CONCLUSION

Downregulation of srGAP1 in CRC was associated with tumor progression and poor prognosis. srGAP1 is an important downstream molecule of Slit2 signalling in CRC, and mediates the anti-migration function of Slit2 by inhibiting Cdc42.

Expression of P21-activated kinase 1 and cell division control protein 42 homolog correlates with clinicopathological features and prognosis in cervical carcinoma

AIM

This study investigated P21-activated kinase 1 (PAK1) and cell division control protein 42 homolog (CDC42) expression and their correlation with clinicopathological features and prognosis in cervical carcinoma.

METHODS

Cervical carcinoma (n = 55), cervical intraepithelial neoplasias (CIN, n = 93), and normal cervix (n = 26) tissues were sampled. PAK1 and CDC42 expressions were determined using real-time quantitative polymerase chain reaction, Western blot and immunohistochemistry. Correlation analysis of PAK1 and CDC42 expression was performed using a Pearson correlation test. Survival rate was calculated using the Kaplan-Meier method. Independent prognostic factors were analyzed by Cox proportional hazard model.

RESULTS

PAK1 and CDC42 expression were positively correlated in all tissues. PAK1 and CDC42 expression in cervical carcinoma tissues were higher than those in normal tissues. PAK1 and CDC42 protein expression in normal cervix, CINI, CINII, CINIII and cervical carcinoma tissues showed a gradually increasing trend. PAK1 and CDC42 expression were correlated with lymph node metastasis, the depth of tumor invasion, the degree of tumor differentiation, histological type and lymphovascular space invasion (LVSI; all P < 0.05). Cox regression analysis showed that the degree of tumor differentiation, PAK1 protein expression, histological type and LVSI are independent risk factors for prognosis of cervical carcinoma.

CONCLUSION

High PAK1 and CDC42 expressions are closely related to the clinicopathological features and poor prognosis of cervical carcinoma, serving as unfavorable prognostic factors.