Hsa-miR-194-5p and hsa-miR-195-5p are down-regulated expressed in high dysplasia HPV-positive Pap smear samples compared to normal cytology HPV-positive Pap smear samples

BACKGROUND

The human papillomavirus (HPV) infection may affect the miRNA expression pattern during cervical cancer (CC) development. To demonstrate the association between high-risk HPVs and the development of cervix dysplasia, we examined the expression patterns of hsa-miR-194-5p and hsa-miR-195-5p in Pap smear samples from southeast Iranian women. We compared samples that were HPV-positive but showed no abnormality in the cytological examination to samples that were HPV-positive and had severe dysplasia.

METHODS

Pap smear samples were obtained from 60 HPV-positive (HPV-16/18) patients with histologically confirmed severe dysplasia (cervical intra-epithelial neoplasia (CIN 3) or carcinoma in situ) and the normal cytology group. The expression of hsa-miR-194-5p and hsa-miR-195-5p was analyzed by real-time quantitative PCR, using specific stem-loop primers and U6 snRNA as the internal reference gene. Clinicopathological features were associated with miRNA expression levels. Furthermore, functional enrichment analysis was conducted using in silico tools. The Kaplan-Meier survival method was also obtained to discriminate survival-significant candidate miRNAs in CC, and receiver operating characteristic (ROC) curves were constructed to assess the diagnostic value.

RESULTS

Compared to HPV-positive cytologically normal Pap smear samples, hsa-miR-194-5p and hsa-miR-195-5p relative expression decreased significantly in HPV-positive patients with a severe dysplasia Pap smear. Kaplan-Meier analysis indicated a significant association between the miR-194 decrease and poor CC survival. In essence, ROC curve analysis showed that miR-194-5p and miR-195-5p could serve as valuable markers for the development of cervix dysplasia in individuals who are positive for high-risk HPVs.

CONCLUSIONS

This study revealed that hsa-miR-194-5p and hsa-miR-195-5p may possess tumor suppressor capabilities in the context of cervical dysplasia progression. However, it remains uncertain whether these microRNAs are implicated in the transition of patients with high dysplasia to cervical cancer. We also showed the potential capability of candidate miRNAs as novel diagnostic biomarkers related to cervical dysplasia progression.

Hsa-miR-195-5p Inhibits Autophagy and Gemcitabine Resistance of Lung Adenocarcinoma Cells via E2F7/CEP55

Lung adenocarcinoma (LUAD) is a common malignancy. Many studies have shown that LUAD is resistant to gemcitabine chemotherapy, resulting in poor treatment outcomes in patients. We designed this study to reveal influences of hsa-miR-195-5p/E2F7/CEP55 axis on gemcitabine resistance and autophagy of LUAD cells. The expression data of LUAD-related mRNAs were downloaded from TCGA-LUAD database for differential expression analysis. The bioinformatics databases (hTFtarget, starBase and TargetScan) were used to predict the upstream and downstream regulatory molecules of E2F7. Then the binding relationships between E2F7 and regulatory molecules were verified by ChIP and dual-luciferase reporter assay. qRT-PCR and western blot were used to detect the mRNA and protein levels of has-miR-195-5p, E2F7, and CEP55. CCK-8 assay was used to analyze the half-maximal inhibitory concentration (IC₅₀) and cell proliferation ability of LUAD cells after gemcitabine treatment. Apoptosis was detected by flow cytometry. Apoptosis/autophagy markers and LC3 aggregation were detected by western blot and immunofluorescence, respectively. Finally, the mouse transplantation model was constructed to verify the regulation mechanism in vivo. In LUAD cells and tissues, E2F7 and CEP55 were highly expressed, while has-miR-195-5p was relatively less expressed. The ChIP or dual-luciferase assays demonstrated the binding relationships of E2F7 to the CEP55 promoter region and has-miR-195-5p to the 3'-UTR of E2F7. Cell experiments demonstrated that overexpression of hsa-miR-195-5p stimulated LUAD cell apoptosis and inhibited autophagy and gemcitabine resistance, while further overexpression E2F7/CEP55 could reverse the impact by hsa-miR-195-5p overexpression. In vivo experiments identified that hsa-miR-195-5p/E2F7/CEP55 axis constrained the growth of LUAD tumor. Hsa-miR-195-5p promoted apoptosis, repressed proliferation, and autophagy via E2F7/CEP55 and reduced gemcitabine resistance in LUAD, indicating that hsa-miR-195-5p/E2F7/CEP55 may be a novel target for LUAD.