Prognostic Value and Related Molecular Mechanisms of miR-5003-3p in Hepatocellular Carcinoma.

[BACKGROUND] Hepatocellular carcinoma (HCC) is a malignant tumor worldwide with a high mortality rate and recurrence rate. Numerous miRNAs are being applied to the healing and prognosis of HCC. A prior investigation predicted that miR-5003-3p was linked to HCC, but the relevant molecular mechanisms were not clear.

[AIM] To discover the prognostic value and molecular mechanisms concerned of miR-5003-3p in HCC.

[METHODS] A total of 125 tumor specimens from HCC patients were obtained in this study, along with corresponding adjacent noncancerous tissue samples collected as a control. The levels of miR-500-3p and MAL2 in tumor tissues and cells were detected by RT-qPCR. The prognostic value of miR-500-3p was evaluated using Kaplan-Meier curve and COX regression model. The effects of miR-500-3p on cellular malignant phenotypes were assessed via CCK-8 and Transwell assays. The target sites of miR-500-3p were identified using bioinformatics analysis. The dual-luciferase reporter assay validated the target relationship between them.

[RESULTS] miR-5003-3p levels were remarkably elevated in HCC tissues, and late TNM stage (I + II) was dramatically higher versus early TNM stage (III + IV). Lymph node metastasis, TNM stage, and differentiated degree were linked notably to miR-5003-3p expression. Upregulated miR-5003-3p was an independent risk factor for HCC. In vitro, downregulated miR-5003-3p could induce apoptosis and restrain proliferation, migration, and invasion, which could be rescued by depressed MAL2.

[CONCLUSION] miR-5003-3p may be an independent prognostic factor for HCC. Mechanistically, miR-5003-3p negatively regulates MAL2 to promote cellular processes. These findings highlight the potential of miR-5003-3p as a novel prognostic biomarker and a promising therapeutic target for HCC.