miR-199a-5p confers tumor-suppressive role in triple-negative breast cancer

Abstract

BackgroundTriple-negative breast cancer (TNBC) remains a poor prognostic factor for breast cancer since no effective targeted therapy is readily available. Our previous studies confirmed miR-199a-5p is a TNBC-specific circulating biomarker, however, its functional roles in breast cancer is largely unknown. Thus, we investigated the functional implication of miR-199a-5p in TNBC and its potential underlying mechanisms.MethodsMTT assay was performed to investigate the cell proliferation after transient transfection of miR-199a-5p in MDA-MB-231 cell line, followed by cell cycle analysis. Transwell invasion assay and wound healing assay were used to study the invasion and migration ability respectively. To further investigate the stemness-related characteristics of miR-199a-5p in breast cancer cells, single-cell clonogenic assay and aldehyde dehydrogenase (ALDH) assay were performed. 32 normal and 100 breast cancer patients’ plasma were recruited to identify the potential circulating markers by qPCR.ResultsCell proliferation assay revealed significant inhibition after miR-199a-5p ectopic expression (p < 0.0001), as a result of decreased S phase (p = 0.0284), increased G0/G1 phase (p = 0.0260) and apoptosis (p = 0.0374). Invasiveness (p = 0.0005) and wound healing ability were also decreased upon miR-199a-5p overexpression. It significantly altered EMT-related genes expression, namely CDH1, ZEB1 and TWIST. Single-cell clonogenic assay showed decreased colonies in miR-199a-5p (p = 0.0182). Significant downregulation (p = 0.0088) and inhibited activity (p = 0.0390) of ALDH was observed in miR-199a-5p. ALDH1A3, which is the dominant isoform of ALDH, is significantly upregulated in breast cancer plasma especially in TNBC (p = 0.0248). PIK3CD was identified as a potential downstream target of miR-199a-5p.ConclusionsTaken together, we unraveled, for the first time, the tumor-suppressive role of miR-199a-5p in TNBC, which attributed to EMT and cancer stemness properties, providing a novel therapeutic options towards this aggressive disease.

Linc00518 Contributes to Multidrug Resistance Through Regulating the MiR-199a/MRP1 Axis in Breast Cancer

“…At 8 days after infection, 0.1 ml PBS or ADR (dissolved in 0.1 ml PBS; 15 mg/kg) was administered intravenously into xenograft mice once every 4 days for 24 days. Body weight and tumor volume were measured at 8,12,16,20,24,28, and 32 days after the first injection. At 32 days post inoculation, mice were killed and tumor masses were resected for weight measurement, RT-qPCR and western blot assays.…”

CAMIRADA: Cancer microRNA association discovery algorithm, a case study on breast cancer

“…Oncogene hsa-miR-199a [30] 0.001486 Tumor suppressor hsa-miR-20a [31] 0.001529 Oncogene hsa-miR-149 [32] 0.0020011 Oncogene hsa-miR-199b [33] 0.00265 Biomarker hsa-miR-519d [38] 0.002863 Oncogene hsa-miR-502 [34] 0.036284 Tumor suppressor for identification of which microRNA is related to cancer, so for showing the influence of them we combined three ranked lists of p-values by sumlog test. By using CAMIRADA, we predicted eight novel microRNAs including hsa-miR-93, hsa-miR-526b, hsa-miR-20b, hsa-miR-199a, hsa-miR-6884, hsa-miR-199b, and hsa-miR-519d associated to breast cancer which are not yet recorded in the disease-microRNA association HMDD and miR2Disease.…”

MicroRNAs Involved in Carcinogenesis, Prognosis, Therapeutic Resistance, and Applications in Human Triple-Negative Breast Cancer

“…Concomitant with the miR-200 family, the negative regulator miR-205 was dramatically reduced in TGF-β-induced cells to undergo EMT via direct targeting of ZEB1/2 [79]. MiR-199a-5p was observed downregulated in TNBC, and overexpression of miR-199a-5p in TNBC cells significantly altered EMT-related genes expression, such as CDH1, ZEB1, and TWIST by targeting of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit delta (PIK3CD), reducing cell motility and invasiveness, as well as repressed tumor cell growth [83]. Similarly, miR-3178 was significantly reduced in TNBC, and the ectopic overexpression of miR-3178 suppressed cell proliferation, invasion, and migration by inhibiting the EMT by targeting of notch receptor 1 (Notch-1) in TNBC [84].…”

“…Oncogenic miRNAs miR-21 PTEN Promotes the tumor proliferation and inhibits cell apoptosis [90] miR-182 PFN1, RIP1 Promote the tumor proliferation, inhibit cell apoptosis and migration [115,168] miR-301b CYLD Inhibits cell apoptosis induced by 5-FU [169] miR-155-5p FOXO3A Promotes proliferation and reduces bufalin-induced apoptosis [170] miR-17-5p/20a DR4/DR5 Inhibit apoptosis [171] miR-429 XIAP Regulates apoptosis [172] Oncosuppressor miRNAs miR-200c XIAP Induces apoptosis [126] miR-31 Bcl-2, PKCε Induce apoptosis, increase sensitivity of chemo-and radiosensitivity [173] miR-4458 SOCS1 Inhibits proliferation and promotes apoptosis [174] miR-890 CD147 Inhibits the cell proliferation and invasion, induces apoptosis [175] miR-509 TNF-α Increases apoptosis and inhibits invasion [176] miR-145 cIAP1 Promotes TNF-α-induced apoptosis [177] miR-199a-5p TGF-β2, PIK3CD Proliferate inhibition, cell cycle arrest, and increase apoptosis [83] miR-1296 CCND1 Suppresses proliferation, cell cycle arrest accompanied by induction of apoptosis [178] miR-10a PIK3CA Inhibits the proliferation and migration, promotes apoptosis [179] Oncosuppressive miRNAs are downregulated in TNBC to promote apoptosis through various signaling pathways, as listed in Table 7. MiR-200c induces apoptosis by targeting the expression of XIAP [126].…”

“…For instance, miR-145 promotes TNF-α-induced apoptosis and facilitates the formation of receptor-interacting protein 1 (RIP1)-Fas-associated death domain (FADD)-caspase-8 complex by targeting cellular inhibitor of apoptosis (cIAP1) in TNBC cells [177]. Chen et al unraveled the tumor-suppressive role of miR-199a-5p in TNBC associated with proliferation inhibition, cell cycle arrest, and increasing apoptosis by regulating the downstream targets of TGF-β2 and PIK3CD [83], and the overexpression of a novel tumor suppressor of miR-1296 involved in suppressed cell proliferation, cell cycle arrest, accompanied by induction of apoptosis by targeting cyclin D1 (CCND1) in TNBC cells [178]. Ke et al showed that miR-10a inhibits proliferation and migration, promotes apoptosis via inhibiting phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA) expression at the post-transcriptional level to suppress phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling, and induces the mitochondrial apoptotic pathway [179].…”