The Studies On The Role Of Rab23in Cell Proliferation Of Cutaneous Squamous Cell Carcinoma And Mechanisms

Cutaneous squamous cell carcinoma (cSCC) is the most common malignant tumor indermatology, accounting for20%of non melanoma-derived malignant tumor just afterbasal cell carcinoma. cSCC possesses invasiveness and metastasis can occurs in the earlystage. In recent decades, the incidence rate of cSCC is progressively increasing, and itthreatens our health. Therefore, the research into the initiation and development of cSCCis of great clinical significance.Rab23is the member of small GTPaseRab, and is also a negative regulator in SonicHedgehog pathway. Rab23is not only involved in the transportation of vesicles, and playdifferent roles in a variety of tumors. Our previous study suggested that Rab23was highlyexpressed in cSCC, and it could promote the invasive of squamous cell. But the effect ofRab23on the growth and proliferation of squamous cell remains unclear. Therefore, thisstudy aims to investigate the effect of Rab23on the growth and proliferation of squamouscell and its preliminary mechanism.Methods and results:1. Effect of Rab23on the growth and proliferation of Sa3squamous cell1) Oral squamous cell carcinoma cell line Sa3was employed to construct Sa3celllines with Rab23overexpression and Rab23knockout. Rab23expression was detected byWestern blot. The results suggested that the fusion protein was successfully transfected in Rab23overexpression group and Rab23expressio n decreased in Rab23knockout groupcompared with empty vector group.2) Plate clone formation assay was performed to detect the effect of Rab23on theproliferation of Sa3cell. The results suggested that the proliferation in Rab23overexpression group decreased compared with the control group and the proliferation inRab23knockout group increased dramatically.3) Flow cytometry were employed to detect the effect of Rab23on Sa3cell cycle.The results suggested that Rab23overexpression led to the block in G1phase in Sa3cell.4) CCK8assay was used to detect the effect of Rab23on Sa3growth. The resultssuggested that Rab23overexpression led to the increase in cell growth compared with thecontrol group and Rab23knockout led to the decrease in cell growth.2. The preliminary study of the mechanism underlying the inhibitory effect of Rab23on the growth and proliferation of Sa3cell1) Western blot was used to detect the expression of Gli1and Gli2in cells withRab23stable transfection. The results suggested that the expression of Gli1and Gli2,which are key proteins in hedgehog pathway, showed no significant changes.2) Western blot was employed to detect the expression of Erk1/2and p-Erk1/2incells with Rab23stable transfection. The results suggested that Erk1/2expression showedno significant changes in Sa3cells with Rab23overexpression and Rab23knockout.Compared with the control group, p-ERK expression decreased in Rab23overexpressiongroup and p-ERK expression increased in Rab23knockout group.3) Western blot was used to detect the expression of cell cycle related protein in cellswith Rab23stable transfection. The results suggested that Cyclin D1expression decreasedin Rab23overexpression group and Cyclin D1expression increased in Rab23knockoutgroup. Cyclin E expression showed no remarkable changes.Conclusions:1) Rab23inhibits the growth and proliferation of Sa3squamous cell.2) The inhibitory effect of Rab23on Sa3cell proliferation may be related toERK-MAPKs signaling pathway, not Sonic hedgehog pathway. 3) Rab23down-regulates Cyclin D1expression in Sa3squamous cell, which led tothe block in G1phase in Sa3cell.