ABSTRACT
BACKGROUND: Increasing evidence has suggested that microRNAs (miRNAs) act as key post-transcriptional regulators in tumor progression. Previous studies have confirmed that miR-17-5p functions as an oncogene in multiple cancers and contributes to tumor progression. However, the role and biological functions of miR-17-5p in the development of laryngeal squamous cell carcinoma (LSCC) still remain unknown. METHODS: qRT-PCR was used to detect miRNA and mRNA expression levels in LSCC tissues and cell lines. CCK-8 assay was used to measure cell viability and flow cytometry was performed to evaluate cell apoptosis. Western blot analysis was used to detect the protein levels of BAX, BCL-2, cleaved Caspase-3, PIK3R1 and AKT. Luciferase reporter assay was used to detect the effect of miR-17-5p on PIK3R1 expression. Xenograft animal model was used to test the effect of miR-17-5p on LSCC cell in vivo. RESULTS: In the present study, we found that miR-17-5p expression level was upregulated in LSCC tissues and cell lines. Depletion of miR-17-5p in LSCC cells significantly reduced cell proliferation and promoted cell apoptosis in vitro and in vivo. Mechanically, knockdown of miR-17-5p in LSCC cells inhibited BCL-2 expression while enhanced BAX and cleaved Caspase-3 protein expression. Moreover, depletion of miR-17-5p in LSCC cells suppressed AKT phosphorylation but did not influence PTEN expression. Importantly, miR-17-5p positively regulated PIK3R1 expression by directly binding to its 3'-untranslated region (UTR). Additionally, PIK3R1, which expression was downregulated in LSCC tissues and cell lines, was involved in LSCC cell survival by modulating the activation of AKT signal pathway. Dysregulation of miR-17-5p/PIK3R1 axis was participated in LSCC cell proliferation and apoptosis by inhibiting the activation of the PI3K/AKT signaling pathway. CONCLUSIONS: In conclusion, our study indicates that the miR-17-5p/PIK3R1 axis plays an essential role in the development of LSCC and provides a potential therapeutic target for LSCC treatment.
ABSTRACT
BACKGROUND: Accumulating evidence shows that circular RNAs (circRNAs) plays vital roles in tumor progression. However, the biological functions of circRNAs in laryngeal squamous cell carcinoma (LSCC) metastasis is still unclear. METHODS: qRT-PCR was used to detect circFLNA, miRNAs and FLNA mRNA expression. Transwell assay and western blot were performed to evaluate cell migration ability and to detect FLNA, MMP2 and MLK1 protein expression, respectively. RNA pull-down analysis was used to find the binding-miRNAs of circFLNA. Luciferase reporter assay was used to examine the effect of circFLNA on miRNAs and miR-486-3p on FLNA expression. RESULTS: In this study, we confirmed that a Filamin A (FLNA)-derived hsa_circ_0092012 known as circFLNA, was upregulated in LSCC, and the higher expression of circFLNA was correlated with LSCC lymph node metastasis. Increased circFLNA facilitates LSCC cell migration ability through upregulating FLNA and MMP2 protein expression. Mechanistically, we find that circFLNA sponges miR-486-3p in LSCC cells, relieving miR-486-3p-induced repression of FLNA which promotes LSCC cell migration. Accordingly, FLNA mRNA is overexpressed in LSCC tissues and a higher FLNA level is correlated with poor survival. Dysregulation of the circFLNA/miR-486-3p/FLNA regulatory pathway contributes to LSCC migration. CONCLUSIONS: In summary, our study sheds light on the regulatory mechanism of circFLNA in LSCC migration via sponging miR-486-3p, which downregulates the FLNA protein expression. Targeting circFLNA/miR-486-3p/FLAN axis provides a potential therapeutic target for aggressive LSCC.
ABSTRACT
OBJECTIVE: To investigate the relationship among expression of heparanase (HPSE), the clinical and pathologic characteristics of squamous carcinoma on head and neck and the patients' prognosis. METHODS: Sixty-two cases of postoperative tumor specimens were verified by immunohistochemistry S-P method and computer-assisted image analysis method was used. RESULTS: The expression of HPSE in normal epithelium mucosae of head and neck was negative or very weak; in tumor tissue was positive, mainly in cytoplasm and the positive rate was 69.3%. The expression of HPSE hadn't significant difference with the age of patients and pathologic grades of tumors (chi2 = 0.05, chi2 = 3.84, P > 0.05), but had it with clinical stages and metastatic lymph node lesions (chi2 = 3.96, chi2 = 8.06, P < 0.05). The relationship between expression of HPSE in primary tumors and that in metastatic lymph node lesions showed significantly positive correlation (r = 0.9162, P = 0.001). Both HPSE and TNM clinical stage of tumor had significant correlation with the prognosis of patients respectively (P < 0.05). Calculated by Kaplan-Meier method, the accumulative survival rate of 3 years in positive HPSE expression group (25.9%) was much lower than that in negative group (72.7%), there was a significant difference between them by Log-Rank test (chi2 = 11.607, P < 0.001). CONCLUSIONS: The expression of HPSE is significantly increased in squamous carcinomas of head and neck, mainly expressed in cytoplasm. The expression of HPSE has a close relationship with clinical stages and lymph node metastasis of squamous carcinoma on head and neck. The higher the clinical stage, the more manifest the expression of HPSE. The expression of HPSE and TNM clinical stage of tumor are independent factors affecting prognosis.
