RBBP6 promotes human cervical carcinoma malignancy via JNK signaling pathway.

Previous studies have shown that retinoblastoma binding protein 6 (RBBP6) was overexpressed in malignant tumors and was correlated with poorer prognosis in various cancers. However, its role in cervical carcinoma has not been elucidated. This study was to investigate the relationship between RBBP6 and cervical carcinoma. Cervical carcinoma cell lines SiHa and C33a were used to assess the effect of RBBP6 on cell viability, migration, and proliferation. RBBP6 mRNA and protein levels in cervical cancer tissues increased at least three times as that in the adjacent non-cancerous tissues. Overexpression of RBBP6 in SiHa and C33a cell lines resulted in increased phosphorylated c-Jun NH2-terminal kinase (p-JNK) as well as increased cell viability, migration, and proliferation. Moreover, this effect was suppressed by specific JNK inhibitor SP600125. RBBP6 might potentiate cervical carcinoma cell viability, migration and proliferation through JNK signaling pathway. RBBP6 and JNK inhibitor may be beneficial as a novel preventive and therapeutic target for cervical cancer.

URI promotes the migration and invasion of human cervical cancer cells potentially via upregulation of vimentin expression.

URI is known to act as an oncoprotein in several tumors. Our previous studies have shown that URI is associated with the migration process in cervical and gastric cancer cells, but the mechanisms remain to be determined. Given the fact that URI positively regulates vimentin expression, we therefore investigated how URI regulated vimentin expression affects the migration and invasion of cells from two human cervical cancer cell lines HeLa and C33A, which differentially express URI. We have shown that knock-down of URI in HeLa cells using URI siRNA caused decreased vimentin mRNA and protein levels along with attenuated cell motility. Meanwhile, overexpression of URI by transfection of PCMV6-URI in C33A cells resulted in increased vimentin expression and enhanced cell migration and invasion. We have also used TGF-ß to induce vimentin expression, which enhanced the cell migration and invasion abilities affected by URI, while inhibition of vimentin by siRNA attenuated URI's effect on cell migration and invasion. In addition, we have performed luciferase reporter and ChIP assays, and the results support that URI indirectly enhances the activity of vimentin promoter. Taken together, our results suggest that URI plays essential roles in the migration and invasion of human cervical cancer cells, possibly via targeting vimentin expression.

[Establishment and identification of human cervical cancer cell line C33A stably expressing human papillomavirus type 58 E6E7 fusion gene].

The study was performed to construct a human cervical cancer cell line C33A which can stably express HPV58E6E7 fusion gene. Firstly, C33A cells were transfected with the recombinant lentivirus LV-HPV58E6E7 which contained HPV58E6E7 fusion gene, and the stably transfected cells (LV-HPV58E6E7/C33A) were screened out by flow cytometry. MTT was used to observe the growth of LV-HPV58E6E7/C33A cells and flow cytometry was carried out to detect the cell cycle. LV-HPV58E6E7/C33A cells were inoculated into the left armpits of nude mice. Then, the transcription and expression of HPV58E6E7 fusion gene was detected by qRT-PCR and Western blot, respectively. The results showed that HPV58E6E7 fusion gene can promote the proliferation of C33A cells. HPV58E6E7 fusion gene can be stably transcripted and expressed in vaccinated nude mice. The conclusion indicated that we successfully established a cervical cancer cell line LV-HPV58E6E7/C33A which can stably express HPV58E6E7 fusion gene. This cell line will provide an antigen cell line for the immune effect detection of HPV58 therapeutic vaccine.

Inductive effects of galangin on apotosis of human papilloma virus positive cervical cancer cells / 中草药

Objective: To explore the inductive effect of galangin on HPV-positive human cervical cancer cells and the possible mechanism. Methods: Two HPV-positive human cervical cancer cell lines (SiHa cell and HeLa cell) and one HPV-negative human cervical cancer cell line (C-33-A cell) were given different concentration of galangin (20, 40, and 80 μmol/L) for 24, 48, and 72 h. Three human cervical cancer cell lines and relative cell viabilities were determined by the MTT method. Apoptosis and cell cycle were analyzed by flow cytometry. Western blotting analysis was used to determine the protein expression levels of Bcl-2 family proteins. Results: Cell proliferation of two HPV-positive human cervical cancer cells was significantly inhibited by galangin in a dose- and time-dependent manner, and galangin had no effect on cell proliferation of HPV-negative human cervical cancer cells. Cell cycle detection results showed that galangin could reversibly arrest the two HPV-positive cell lines, either in G1 or in G2/M phases. Flow cytometry results showed that beyond certain galangin concentration or/and over 24 h exposure, the cells underwent apoptosis. The data of Western blotting showed that 40 μmol/L galangin up-regulated the expression levels of Bad, Bid, and Bax, but down-regulated Bcl-2 and Bcl-w. Conclusion: Galangin can inhibit the proliferation of HPV-positive cervical cancer cells and promote apoptosis, which may be associated with the regulation of Bcl-2 family proteins expression.