High-risk human papillomavirus (hrHPVs), particularly HPV16 and HPV18, are the etiologic factors of ano-genital cancers and some head and neck squamous cell carcinomas (HNSCCs). Viral E6 and E7 oncoproteins, controlled at both transcriptional and post-transcriptional levels, drive hrHPVs-induced carcinogenesis. In the present study, we investigated the implication of the DEAD-box helicase eukaryotic translation initiation factor 4A3 (eIF4A3,) an Exon Junction Complex factor, in the regulation of HPV16 gene expression. Our data revealed that the depletion of the factor eIF4A3 up-regulated E7 oncoprotein levels. We also showed that the inhibition of the nonsense-mediated RNA decay (NMD) pathway, resulted in the up-regulation of E7 at both RNA and protein levels. We therefore proposed that HPV16 transcripts might present different susceptibilities to NMD and that this pathway could play a key role in the levels of expression of these viral oncoproteins during the development of HPV-related cancers.

Background: Little research has been done on clinicopathological characteristics and human papillomavirus (HPV) status of anogenital and oropharyngeal squamous cell carcinomas (SCC) with a strong expression of programmed death ligand 1 (PD-L1) in tumor cells. Therefore, we conducted this meta-analysis. Methods: We performed a comprehensive research in PubMed, Embase and Cochrane databases up to 30 September 2020. The effect size was hazard ratio (HR) with 95% confidence interval (CI) for overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS). The pooled odds ratio (OR) with 95% CI were used to assess the association between PD-L1 expression and clinicopathological features along with HPV status. Results: A total of 2003 cases (944 anogenital and 1059 oropharynx SCC patients) were included. High PD-L1 expression in anogenital SCC cases were associated with advanced age (OR = 1.63, 95% CI: 1.04–2.58) and HPV negativity (OR = 0.47, 95% CI: 0.31–0.71). Besides, PD-L1 positive anogenital SCC cases held a significantly declined OS (HR = 2.18, 95% CI: 1.37–3.47) and CSS (HR = 2.45, 95% CI: 1.30–4.65). For oropharynx SCC, PD-L1 was more frequent in younger and HPV positive patients (OR = 0.60, 95% CI: 0.37–0.98; OR = 3.01, 95% CI: 1.78–5.09) and PD-L1 expression was relevant to better OS and DFS (HR = 0.76, 95% CI: 0.60–0.97; HR = 0.50, 95% CI: 0.33–0.75). Conclusions: The meta-analysis demonstrated that in anogenital SCC, PD-L1 positivity had to do with a worse outcome, which might attribute to advanced age, higher tumor grade, lymph node metastasis and HPV negativity, while in oropharynx cancer, PD-L1 expression was related to better prognosis for the reason that PD-L1 was less frequent in the aged and negative HPV status.

LncRNA SRA1 plays important roles in several types of human diseases. The present study aimed to explore the role of SRA1 in cervical squamous cell carcinoma (CSCC). In the present study, we showed that plasma SRA1 was down-regulated in human papillomavirus (HPV)-negative CSCC patients but not in HPV-positive CSCC patients compared with healthy females. Down-regulated SRA1 distinguished HPV-negative CSCC patients from HPV-positive CSCC patients and healthy females. In HPV-negative CSCC patients, miR-9 was up-regulated and inversely correlated with SRA1. In HPV-negative CSCC cells, SRA1 overexpression caused the down-regulated miR-9, while miR-9 overexpression failed to affect SRA1. Moreover, SRA1 overexpression caused decreased, while miR-9 overexpression caused increased proliferation, migration and invasion rates of cancer cells. In addition, miR-9 overexpression attenuated the effects of SRA1 overexpression. Therefore, SRA1 is down-regulated in HPV-negative CSCC and regulates cancer cell behaviors possibly by down-regulating miR-9.

LncRNA NEF was a recently identified tumor suppressor lncRNA in hepatocellular carcinoma. Our study aimed to explore the role of NEF in cervical squamous cell carcinoma (CSCC) patients. In the present study, expression of NEF in tumor tissue (cervical biopsies for healthy control) and serum of human papillomaviruses (HPV)-negative and HPV-positive CSCC patients as well as healthy controls was detected by qRT-PCR. Diagnostic and prognostic values of NEF for CSCC were evaluated by ROC curve and survival curve analysis, respectively. NEF expression vector was transfected into CSCC cells and the effects on cell migration and invasion as well as TGF-β1 expression were investigated by Transwell migration assay, Transwell invasion assay, and Western blot, respectively. We found that expression of NEF in cervical tissues (tumor tissues for CSCC patients) and serum was significantly down-regulated in HPV-negative CSCC patients than in healthy controls and HPV positive patients, but no significant differences were found between healthy controls and HPV positive patients. Low serum levels of NEF distinguished HPV-negative CSCC patients from healthy controls and indicated poor survival. NEF overexpression inhibited the migration and invasion of HPV-negative but not HPV-positive CSCC cells. NEF overexpression down-regulated TGF-β1 in HPV-negative CSCC cells but not in HPV-positive CSCC cells. TGF-β1 treatment reduced the effects of NEF overexpression on cell migration and invasion. Therefore, we conclude that lncRNA NEF may inhibit the migration and invasion of HPV-negative cervical squamous cell carcinoma by inhibiting TGF-β pathway.