[Inhibition of HPV16 E6 oncogene in cervical cancer by RNA interference].

OBJECTIVE: The efficiency of HPV16 E6 gene silenced by RNA interference in vitro and in vivo was assessed. METHODS: The specific siRNA of HPV16 E6 was designed and transfected into CaSki cells by liposome. Cell apoptotic rates and the changes in HPV16 E6 mRNA and protein before and after transfection were measured. Cervical cancer nude mice models were set up, siRNA was injected directly into subcutaneous tumor. The function of siRNA was evaluated by the changes in tumor volume, HPV16 E6 protein expression and apoptosis of tumor cells. RESULTS: In vitro research, the cell apoptotic rates were 7.7%, 11.8%, 37.4% and 12.6% respectively at 24 h, 48 h, 5th day and 9th day after transfection. The HPV16 E6 mRNA was reduced by 77%, 83%, 59% and 41% at 24 h, 48 h, 5th day and 9th day after transfection. The inhibition rates of E6 protein measured by Flow cytometry were 79.7%, 80.4%, 71.3% and 57.4% at 24 h, 48 h, 5th day and 9th day after transfection, which were confirmed by the results of Western blot. In vivo research, E6 siRNA administration groups had great power in inhibiting tumor growth, restraining E6 protein expression, increasing tumor necrosis and apoptosis. The result of repeated injections of siRNA was better than that of single injection. CONCLUSION: RNA interference with HPV16 E6 is specific and highly efficient in vitro and in vivo.

[Chemosensitivity testing of topotecan as second-line agent in chemotherapy of ovarian cancer].

BACKGROUND & OBJECTIVE: The therapeutic principle of ovarian cancer was cytoreductive surgery assisting with chemotherapy. At present, cisplatin-based chemotherapy is the primary way for treatment of ovarian cancer. But most patients with advanced ovarian cancer were easy to recurrent and then become resistance to cisplatin. This study was designed to evaluate the clinical application of topotecan in recurrent ovarian cancer and ovarian cancer resistant to cisplatin. METHODS: An adenosine triphosphate chemosensitivity assay (ATP-CSA) was used to determine the drug sensitivity of 41 tissue specimens of fresh ovarian cancer. Cisplatin and topotecan were used as chemotherapeutic agents [1xPeak Plasma Concentration (PPC)], and then the results were analyzed. RESULTS: (1) In 41 specimens, the results showed that topotecan was more sensitive (80.5%) than cisplatin (51.2%). (2) In 20 cisplatin-resistance specimens, there were 18 specimens sensitive to topotecan. CONCLUSIONS: Topotecan could be a kind of better second line drug in treating ovarian cancer, particularly when the patient was resistant to cisplatin.

[Tissue microarray and in situ hybridization study on hypoxia inducible factor 1alpha mRNA expression in epithelial ovarian tumor].

OBJECTIVE: To study the expression and significance of hypoxia inducible factor 1alpha (HIF-1alpha) in epithelial ovarian tumors. METHODS: The expression of HIF-1alpha mRNA in 295 patients with epithelial ovarian tumor was analyzed retrospectively by high-throughput tissue microarray and in situ hybridization, which was compared with 13 normal ovarian tissue samples. RESULTS: The expression rates of HIF-1alpha mRNA were 0, 13.2%, 42.1% and 81.9% in normal ovarian tissue, benign, borderline and malignant ovarian tumors. Expression rate of HIF-1alpha mRNA in borderline and invasive tumor was significantly higher than those in normal ovarian tissue and benign tumor (P < 0.001). Statistical analysis revealed that the expression of HIF-1alpha mRNA was not related to FIGO stages or histological subtypes. Close negative relation was observed between the expression of HIF-1alpha mRNA and tumor histological differentiation (P < 0.001). CONCLUSION: The overexpression of HIF-1alpha may play an important role in oncogenesis of epithelial ovarian tumor. Tissue microarray is an efficient technique of molecular biology.

[Expression of lung resistant-related protein in ovarian cancer and its clinical significance].

BACKGROUND & OBJECTIVE: It was reported that there was negative correlation between the over-expression of lung resistant-related protein (LRP) and the sensitivity of cisplatin and cyclophosphamide. Also it was reported that the over-expression of LRP could predict the chemosensitivity and prognosis of ovarian cancer, and it was an independent index of remission and exist period. This study was designed to investigate the function of LRP in cisplatin resistance and the relationship with prognosis of ovarian cancer by combining with the chemosensitivity test. METHOD: 1. ATP bioluminescence assay was used to determine the drug sensitivity of 50 specimens of fresh epithelial ovarian cancer tissues. Patients' responses were obtained by accepted clinical assessment methods after three treatment courses. 2. Expression of LRP in 50 paraffin specimens of ovarian cancer was determined using immunohistochemistry. RESULTS: 1. The non-overexpression of LRP in ovarian cancer was 24%, and the overexpression of LRP was 76%. 2. The non-overexpression of LRP in the cisplatin-sensitive ovarian cancer was 10/12(75%), while in the cisplatin-resistance was 3/12(25%). There was no significantly different. 3. The over-expression of LRP was increased in advanced and low grade ovarian cancer, and there was significantly different. CONCLUSIONS: Expression of LRP is related to stages, grades, and chemosensitivity of ovarian cancer, and it could become an index of screening drug and judging the prognosis of patients.