Background: Telomerase activity is a cancer hallmark, and hTERT is the rate-limiting catalytic subunit of telomerase. In human papillomavirus type 16 E6 (16E6)-expressing epithelial cells, NFX1-123 augments and is required for full hTERT expression, leading to a growth advantage. However, no studies have investigated the role of NFX1-123 in telomerase activity regulation in HPV-associated cancers. Methods: We knocked out NFX1-123 in CaSki cells (CaSki KO) and performed single-cell RNA sequencing to determine mRNA alterations affected by reduced NFX1-123. Results: In CaSki KO cells, there were three cell clusters based on gene expression, each associated with different enriched biological processes. When pooled and compared with control cells, CaSki KO cells had 1661 decreased and 565 increased mRNAs involving RNA regulation, cell cycle and division, chromatin regulation, and carcinogenesis processes and pathways. CENP-F, a cell cycle and chromosome segregation gene increased in cervical cancers, was among 10 genes with the greatest decrease in mRNA expression in CaSki KO cells. CaSki and SiHa cells with either reduced NFX1-123 or knocked down HPV 16 E6 and E7, demonstrated reducedhTERT,CENP-F, and telomerase activity, and when both NFX1-123 and HPV 16 E6 and E7 were decreased,hTERTand telomerase activity fell further. Finally,hTERTandCENP-Fwere increased in cervical cancer primary tumors and in HPV-positive head and neck cancer primary tumors in the TCGA database. Conclusions: These findings highlight the shared role that NFX1-123 has with HPV 16 oncogenes in driving and maintaining RNA, cell cycle, and carcinogenesis pathways, and specifically regulating hTERT, telomerase, and CENP-F.
背景：端粒酶活性是癌症的标志性特征，而hTERT是端粒酶的限速催化亚基。在表达人乳头瘤病毒16型E6（16E6）蛋白的上皮细胞中，NFX1-123能增强并是实现hTERT完全表达所必需的，从而促进细胞生长优势。然而，目前尚无研究探讨NFX1-123在HPV相关癌症中对端粒酶活性调控的作用。方法：我们在CaSki细胞中敲除NFX1-123（CaSki KO），并通过单细胞RNA测序分析NFX1-123减少导致的mRNA表达变化。结果：在CaSki KO细胞中，根据基因表达特征可区分为三个细胞簇，每个细胞簇与不同的富集生物学过程相关。将细胞簇合并后与对照组比较，CaSki KO细胞中有1661个mRNA表达下调、565个表达上调，涉及RNA调控、细胞周期与分裂、染色质调控以及致癌过程和通路。其中，在宫颈癌中高表达的细胞周期与染色体分离相关基因CENP-F，是CaSki KO细胞中mRNA表达下降最显著的10个基因之一。在NFX1-123表达降低或HPV 16 E6/E7被敲低的CaSki和SiHa细胞中，hTERT、CENP-F表达及端粒酶活性均下降；当NFX1-123与HPV 16 E6/E7同时降低时，hTERT表达和端粒酶活性进一步减弱。最后，TCGA数据库分析显示，hTERT和CENP-F在宫颈癌原发肿瘤及HPV阳性头颈癌原发肿瘤中表达上调。结论：这些发现揭示了NFX1-123与HPV 16癌基因在驱动和维持RNA调控、细胞周期及致癌通路中的共同作用，并特别阐明了其对hTERT、端粒酶及CENP-F的特异性调控机制。
肿瘤(癌症)患者之家