In vivo and in vitro experiments both showed that SNHG7 targeted miR-34a and promoted epithelial-to-mesenchymal transition (EMT) initiation and the Notch-1 pathway in breast cancer.
Thus miR-9 and miR-34a have the capability for distinguishing tumor tissues from healthy tissues and the study of their expression levels in tissue may be used as a biomarker for the diagnosis of breast cancer patients from healthy women.
These multiple roles of miR-34a are maintained in a model of human breast cancer, in which chronic expression of miR-34a in triple-negative mesenchymal-like cells (enriched in cancer stem cells-CSCs) could promote a luminal-like differentiation programme, restrict the CSC pool, and inhibit tumour propagation.
Epigenetic origin of the link between obesity and breast cancer (BC) is investigated in a cohort of Tunisian patients, focusing on polymorphism at germline level (miR-146a) and on expression in mammary tumors (miR-21, miR-146a, and miR-34a), according to body mass index (BMI) and clinico-pathologic features.
Conclusion: MicroRNA-34a expression is significantly decreased in the patients' serum with the cancer of breast, and miRNA-34a can be employed as a potential non-invasive molecular marker for the early diagnosis of BC.
MDA-MB-231 and SK-BR-3 human breast cancer cell lines were cultured and transfected twice with hsa-miR-16-5p and hsa-miR-34a-5p mimics individually or in combination.
MIR34a methylation was significantly associated with cancer and the invasive ductal carcinoma type of breast cancer (P=0.015 and P=0.02, respectively).
While miR-34a provides valuable information for diagnosis and staging, combination with tumor markers CA15-3 or CEA improves the sensitivity for breast cancer detection.
Therefore, the present study aimed to investigate the expression and role of miR-34a in breast cancer, and to further explore the underlying molecular mechanism.
The developed miR-34a nanoplexes inhibited the breast cancer cell growth as confirmed by MTT assay wherein 28% and 34% cancer cell viability was observed in 4T1 and MCF-7 cells, respectively.
A better understanding of the molecular mechanisms of miR-34s will open new opportunities for the development of novel therapeutic strategies and define a new approach in identifying potential biomarkers for early diagnosis of breast cancer.
Results showed that co-delivery of miR-34a and TQ is able to inactivate EMT signaling pathway by directly targeting TWIST1 and ZEB1 in BT-549 cell line, indicating that they might be a promising therapeutic combination against breast cancer metastasis.
The expression of shrimp miR-34 in breast cancer cells and in mice suppressed the growth and metastasis of breast cancer by targeting human CCND1, CDK6, CCNE2, E2F3, FOSL1, and MET genes in a cross-phylum manner.
In bone metastasis miR-34a-5p absence inversely correlates with Met expression, while Met oncogene is unaffected by miR-34a-5p in non-metastatic and metastatic breast carcinomas.