ABSTRACT
Pancreatic cancer remains one of the deadliest cancer types with few effective treatment options. While the overexpression of ubiquitin-specific protease 14 (USP14) has been observed in many tumor cells, including pancreatic cancer cells, its precise role in pancreatic cancer is not well defined. Here, we investigated the biological function of USP14 in pancreatic cancer and its molecular mechanisms. Our analysis of the Cancer Genome Atlas database revealed that USP14 was highly expressed in pancreatic cancer tissues,and further investigation revealed that its expression level was negatively correlated with the prognosis of patients. In SW1990 and MIAPaCa2 pancreatic cancer cells,we established stable USP14-knockdown cell lines using the shRNA-USP14 lentivirus and found that USP14 knockdown inhibited the proliferation and migration ability of pancreatic cancer cells by CCK8, colony formation assay, wound-healing and Transwell assays. Western blotting analysis showed that downregulation of USP14 expression resulted in a decrease in CyclinD3 protein levels, while overexpression of USP14 increased the protein levels in SW1990 and MIAPaCa2 pancreatic cancer cells. Furthermore, co-immunoprecipitation demonstrated that USP14 interacts with CyclinD3 and ubiquitination assays show that overexpression of USP14 reduces the ubiquitination level of CyclinD3. Moreover, CRISPR / Cas9-mediated USP14 knockout in SW1990 pancreatic cancer cells resulted in decreased CyclinD3 protein levels. These findings suggest that USP14 promotes the proliferation and migration ability of pancreatic cancer cells by interacting with CyclinD3, highlighting USP14 as a potential therapeutic target for pancreatic cancer.
ABSTRACT
The anti-cancer effects of betulinic acid (BA) on Jurkat cells and its in vitro mechanism were examined by using MTT assay. Apoptosis was detected by using Hoechst33258 staining and annexin-V/PI double-labeled cytometry. The effects of betulinic acid on the cell cycle of Jurkat cells were studied by propidium iodide method. RT-PCR and Western blotting were used to analyze the changes of cyclin D3, bcl-xl mRNA and protein levels in Jurkat cells after treatment with betulinic acid. Our results showed the proliferation of Jurkat cells was decreased in betulinic acid-treated group with a 24-h IC50 value being 70.00 μmol/L. Betulinic acid induced apoptosis of Jurkat cells in a time- and dose-dependent manner. The number of Jurkat cells treated with betulinic acid showed an increase in G0/G1 phase and decrease in S phase. After treatment with 0, 20, 60, 100 μmol/L betulinic acid for 24 h, the number of Jurkat cells was increased from (31.00±1.25)% to (58.84±0.32)% in G0/G1 phase, whereas it was decreased from (61.45±1.04)% to (35.82±1.95)% in S phase. PBMCs were less sensitive to the cytotoxicity of betulinic acid than Jurkat cells. The expressions of cyclin D3,bel-xl mRNA and protein were decreased sharply in Jurkat cells treated with betulinic acid. It is coneluded that betulinic acid is able to inhibit the proliferation of Jurkat cells by regulating the cell cycle,arrest cells at G0/G1 phase and induce the cell apoptosis. The anti-tumor effects of betulinic acid are related to the down-regulated expression of cyclin D3 and bcl-xl.
ABSTRACT
Objective To investigate the anticancer effects and molecular mechanism of betulinic acid (BA)on Raji cells in vitro.Methods The effects of BA on the growth of Raji cells were studied by MTT assay.Apoptosis was assessed by Annexin-V/PI double-labeled cytometry.The influence on cell cycle was studied by flow cytometer.The cyclin D3 mRNA expression was checked by Western blotting and RT-PCR techniques.Results BA showed obvious inhibition on proliferation,as well as induction potency of apoptosis on Raji cells in vitro in a time-and dose-dependent manner by Annexin-V/PI double-labeled method.With the IC_(50)value for 24 h being(39.44?0.65)?g/mL,Raji cells treated with BA showed ac- cumulation in G_0/G_1 phase and reduction in the percentage of cells in S phase.The cyclin D3 mRNA ex- pression and protein were sharply decreased in Raji cells treated with BA.Conclusion BA could inhibit the proliferation of Raji cells by regulating the cell cycle that arrests cells at G_0/G_1 phase and induces apop- tosis of Raji cells.The antitumor effects of BA may be related to down-regulation of the expression of cy- clin D3.