OBJECTIVES: To investigate the regulatory role of Ral guanine nucleotide dissociation stimulator-like 1 (RGL1) in metastasis of colorectal cancer (CRC). METHODS: We analyzed the differential expression of RGL1 between metastatic and non-metastatic CRC in GEO database, and examined its expression in 25 patients with metastatic CRC and 25 patients with non-metastatic CRC treated in Zhujiang Hospital between January, 2020 and December, 2022 using quantitative PCR (qPCR) and immunohistochemistry. HCT116 cell lines with stable RGL1 overexpression and SW480 cells with RGL1 knockdown were established using lentiviral vecors, and the changes in invasion and migration abilities of the cells were assessed using Transwell invasion and migration assays. The transduced cells were injected into the serosa of the cecum of nude mice, and tumor growth and liver metastasis were observed 8 weeks later. Fibronectin adhesion assays and immunofluorescence experiments were employed to assess the relationship between RGL1 and focal adhesion formation, and co-immuno-precipitation assays were performed to explore the interaction between RGL1 and GTPase activation. RESULTS: Compared with non-metastatic CRC, metastatic CRC showed significantly upregulated expression of RGL1. HCT116 cells overexpressing RGL1 exhibited obviously enhanced migration and invasion in vitro with increased capacity for liver metastasis in nude mice. RGL1 overexpression strongly accelerated focal adhesion assembly, facilitated the formation of motile focal adhesions, and enhanced the binding of activated CDC42/RAC1 complex to RGL1. CONCLUSIONS RGL1 is highly expressed in metastatic CRC and promotes distant metastasis of CRC by activating the CDC42/RAC1 complex to facilitate the formation of motile focal adhesions. These findings suggest that RGL1 can potentially serve as a therapeutic target for CRC metastasis.
Humans ; Colorectal Neoplasms/metabolism* ; cdc42 GTP-Binding Protein/metabolism* ; Animals ; Mice, Nude ; rac1 GTP-Binding Protein/metabolism* ; Cell Movement ; Mice ; Focal Adhesions/metabolism* ; Neoplasm Metastasis ; Cell Line, Tumor ; HCT116 Cells ; Up-Regulation ; Neoplasm Invasiveness ; Adaptor Proteins, Signal Transducing ; Female ; Rho Guanine Nucleotide Exchange Factors

OBJECTIVE: To explore the association between expression of ADAM17 and cetuximad resistance in human colorectal cancer SW480 cells. METHODS: The expression of ADAM17 was detected using Western blotting in different human colorectal cancer cell lines, and the cells highly expressing ADAM17 were selected as the target cells. SW480 cells were transfected with ADAM17-siRNA 1 and ADAM17-siRNA 2 and the changes in the expression of ADAM17 protein were detected using Western blotting. SW480 cells were exposed to cetuximad for 24 h and the cell apoptosis was analyzed using flow cytometry. Transwell assay was used to examine the migration ability of SW480 cells with different expression levels of ADAM17; Western blotting was used to analyze the changes in the expressions of AKT signaling pathway-related proteins in the treated cells. RESULTS: The baseline expressions of ADAM17 were significantly higher in SW480 cells than in the other human colorectal cancer cell lines tested ( < 0.05). Both ADAM17-siRNA 1 and 2 effectively reduced the expression of ADAM17 protein in SW480 cells. Knockdown of ADAM17 with siRNA 1 significantly increased the sensitivity of SW480 cells to tocetuximad ( < 0.05), obviously inhibited the cell proliferation, migration and invasion, and significantly reduced the expressions of p-EGFR and p-AKT in the cells ( < 0.001). CONCLUSIONS ADAM17 knockdown obviously inhibits EGFR-AKT signaling pathway and increases the sensitivity of SW480 cells to tocetuximad.
ADAM17 Protein ; genetics ; metabolism ; Antineoplastic Agents, Immunological ; pharmacology ; Apoptosis ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cetuximab ; pharmacology ; Colorectal Neoplasms ; drug therapy ; genetics ; metabolism ; pathology ; Drug Resistance, Neoplasm ; genetics ; ErbB Receptors ; metabolism ; Gene Knockdown Techniques ; Humans ; Neoplasm Invasiveness ; Oncogene Protein v-akt ; metabolism ; RNA, Small Interfering ; Signal Transduction ; Transfection ; methods

OBJECTIVETo investigate Runx3 and C-myc expressions in colorectal cancer and their relationship with the clinicopathological parameters.

METHODSReal-time quantitative PCR was used to detect Runx3 and C-myc mRNA expressions in 38 colorectal cancer tissues and matched adjacent tissues, and Runx3 and C-myc expressions was detected by Western blotting in 63 pairs of colorectal cancer and adjacent tissues. The results were stratified according to the clinicopathological characteristics to examine the relationship of Runx3 and C-myc expressions with the clinicopathological factors in the patients.

RESULTSRunx3 expression was down-regulated and C-myc expression up-regulated at both mRNA and protein levels in colorectal cancer tissues compared with the normal tissues, and their protein expressions exhibited an inverse correlation (r=-0.398, P=0.001). Runx3 and C-myc expressions differed significantly between tumors with different Dukes stages, depths of tumor invasion, lymph node statuses, or histological differentiation (P<0.05); Runx3 down-regulation and C-myc up-regulation were more obvious in tumors in advanced Dukes stage and in poorly differentiated tumors.

CONCLUSIONAbnormal expressions in Runx3 and C-myc may contribute to the occurrence and development of colorectal cancer and are closed correlated with the patient's clinicopathological parameters.

Blotting, Western ; Cell Differentiation ; Colorectal Neoplasms ; genetics ; metabolism ; Core Binding Factor Alpha 3 Subunit ; genetics ; metabolism ; Down-Regulation ; Humans ; Proto-Oncogene Proteins c-myc ; genetics ; metabolism ; RNA, Messenger ; Real-Time Polymerase Chain Reaction ; Up-Regulation

Objective To investigate Runx3 and C-myc expressions in colorectal cancer and their relationship with the clinicopathological parameters. Methods Real-time quantitative PCR was used to detect Runx3 and C-myc mRNA expressions in 38 colorectal cancer tissues and matched adjacent tissues, and Runx3 and C-myc expressions was detected by Western blotting in 63 pairs of colorectal cancer and adjacent tissues. The results were stratified according to the clinicopathological characteristics to examine the relationship of Runx3 and C-myc expressions with the clinicopathological factors in the patients. Results Runx3 expression was down-regulated and C-myc expression up-regulated at both mRNA and protein levels in colorectal cancer tissues compared with the normal tissues, and their protein expressions exhibited an inverse correlation (r=-0.398, P=0.001). Runx3 and C-myc expressions differed significantly between tumors with different Dukes stages, depths of tumor invasion, lymph node statuses, or histological differentiation (P<0.05);Runx3 down-regulation and C-myc up-regulation were more obvious in tumors in advanced Dukes stage and in poorly differentiated tumors. Conclusion Abnormal expressions in Runx3 and C-myc may contribute to the occurrence and development of colorectal cancer and are closed correlated with the patient's clinicopathological parameters.

Objective To investigate Runx3 and C-myc expressions in colorectal cancer and their relationship with the clinicopathological parameters. Methods Real-time quantitative PCR was used to detect Runx3 and C-myc mRNA expressions in 38 colorectal cancer tissues and matched adjacent tissues, and Runx3 and C-myc expressions was detected by Western blotting in 63 pairs of colorectal cancer and adjacent tissues. The results were stratified according to the clinicopathological characteristics to examine the relationship of Runx3 and C-myc expressions with the clinicopathological factors in the patients. Results Runx3 expression was down-regulated and C-myc expression up-regulated at both mRNA and protein levels in colorectal cancer tissues compared with the normal tissues, and their protein expressions exhibited an inverse correlation (r=-0.398, P=0.001). Runx3 and C-myc expressions differed significantly between tumors with different Dukes stages, depths of tumor invasion, lymph node statuses, or histological differentiation (P<0.05);Runx3 down-regulation and C-myc up-regulation were more obvious in tumors in advanced Dukes stage and in poorly differentiated tumors. Conclusion Abnormal expressions in Runx3 and C-myc may contribute to the occurrence and development of colorectal cancer and are closed correlated with the patient's clinicopathological parameters.

The study of RunX3 in tumor pathogenesis is a rapidly expanding area of cancer research.Functional inactivation of RunX3 is frequently observed in tumors of diverse origins.RunX3 can bind directly to the TGF-β signaling effectors for synergistic induction,enhancing the growth inhibitory effect of TGF-β signal pathway.Additionally,RunX3 can also bind to the complex TCF4-β-catenin in Wnt signal pathway for inhibiting its tumorigenicity.Through the two signal pathway mentioned above,RunX3 can regulate the epithelial mesenchymal transitions process.Moreover,the transcription of claudin-1 can be directly regulated by RunX3.RunX3 has also been described to have an oncogenic function in a subset of tumors,but how RunX3 switches from tumor suppression to oncogenic activity is yet unknown.This review focuses on summarizing the important findings about the mechanism and relative signal pathway of RunX3 in tumor suppression from the articles published recently.