Investigator
Capital Medical University
Effect of neoadjuvant chemotherapy followed by surgery for FIGO stage I–II cervical cancer: a meta-analysis
Objective In this meta-analysis, we aimed to evaluate the oncological outcomes of preoperative neoadjuvant chemotherapy followed by radical surgery compared with radical surgery alone for treatment of International Federation of Gynecology and Obstetrics (FIGO) stage I–II cervical cancer. Method We searched for studies comparing the safety and efficacy of neoadjuvant chemotherapy plus surgery versus surgery alone in treatment outcomes of locally advanced cervical cancer. Meta-analysis was used to calculate the pooled odds ratios with corresponding 95% confidence intervals (CI). Results Sixteen studies were included in our analysis. Pooled analysis of overall survival rate [odds ratio (OR) = 1.09, 95% CI: 0.83–1.43] and progression-free survival rate (OR = 1.10, 95% CI: 0.77–1.57) showed that preoperative neoadjuvant chemotherapy did not have a benefit compared with surgery alone in terms of survival rates. The pooled results for postoperative parameters indicated that preoperative neoadjuvant chemotherapy followed by radical surgery was associated with a high rate of vascular space involvement (OR = 0.25, 95% CI: 0.17–0.35) and parametrial infiltration (OR = 0.60, 95% CI: 0.45–0.79). Conclusions This meta-analysis indicated that surgery following neoadjuvant chemotherapy for FIGO stage I–II cervical cancer and surgery alone had similar oncological outcomes.
Novel role of PAF1 in attenuating radiosensitivity in cervical cancer by inhibiting IER5 transcription
Abstract Background Radiosensitivity is limited in cervical cancer (CC) patients due to acquired radiation resistance. In our previous studies, we found that immediate-early response 5 (IER5) is upregulated in CC cells upon radiation exposure and decreases cell survival by promoting apoptosis. The details on the transcriptional regulation of radiation-induced IER5 expression are unknown. Studies in recent years have suggested that Pol II-associated factor 1 (PAF1) is a pivotal transcription factor for certain genes “induced” during tumor progression. In this study, we investigated the role of PAF1 in regulating IER5 expression during CC radiotherapy. Methods PAF1 expression in CC cells was measured by western blotting, immunohistochemistry, and qRT-PCR, and the localization of PAF1 and IER5 was determined by immunofluorescence. The effect of PAF1 and IER5 knockdown by siRNA in Siha and Hela cells was studied by western blotting, qRT-PCR, CCK-8 assay, and flow cytometry. The physical interaction of PAF1 with the IER5 promoter and enhancers was confirmed using chromatin immunoprecipitation and qPCR with or without enhancers knockout by CRISPR/Cas9. Results We confirmed that PAF1 was highly expressed in CC cells and that relatively low expression of IER5 was observed in cells with highly expressed PAF1 in the nucleus. PAF1 knockdown in Siha and Hela cells was associated with increased expression of IER5, reduced cell viability and higher apoptosis rate in response to radiation exposure, while simultaneous PAF1 and IER5 knockdown had little effect on the proportion of apoptotic cells. We also found that PAF1 hindered the transcription of IER5 by promoting Pol II pausing at the promoter-proximal region, which was primarily due to the binding of PAF1 at the enhancers. Conclusions PAF1 reduces CC radiosensitivity by inhibiting IER5 transcription, at least in part by regulating its enhancers. PAF1 might be a potential therapeutic target for overcoming radiation resistance in CC patients.
Quantitative analysis of proteins related to chemoresistance to paclitaxel and carboplatin in human SiHa cervical cancer cells via iTRAQ
This study aimed to identify proteins related to paclitaxel and carboplatin chemoresistance in cervical cancer. Quantitative proteomic analysis was performed on normal SiHa cells and those treated with paclitaxel and carboplatin for 14 days, with isobaric tags for relative and absolute quantitation (iTRAQ) analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to identify related processes and differentially expressed proteins. A total of 67 and 96 differentially expressed proteins were identified in the paclitaxel- and carboplatin- treated groups, respectively. GO and KEGG enrichment analyses identified 53 (43 upregulated and 10 downregulated) and 85 differentially expressed proteins (70 upregulated and 15 downregulated) in the paclitaxel- and carboplatin-treated groups, respectively. The cell counting kit-8 results revealed that APOA1 was overexpressed in both the paclitaxel- and carboplatin- resistant SiHa cells compared with the control cells. Immunohistochemistry showed that APOA1 was highly expressed in the paclitaxel- and carboplatin- resistant squamous cell carcinoma of the cervix. This study is the first to use iTRAQ to identify paclitaxel- and carboplatin- resistance proteins in cervical cells. We identified several proteins previously unassociated with paclitaxel and carboplatin resistance in cervical cancer, thereby expanding our understanding of paclitaxel and carboplatin resistance mechanisms. Moreover, these findings indicate that the APOA1 protein could serve as a potential marker for monitoring and predicting paclitaxel and carboplatin resistance levels.