Advances in Understanding Mitochondrial MicroRNAs (mitomiRs) on the Pathogenesis of Triple-Negative Breast Cancer (TNBC)

Table 3

Roles and mechanisms of mitomiRs in cell apoptosis.

mitomiR	Function	Target gene	Mechanism of action	Effect on TNBC	PMID	Reference
miR-34a	(-)TNBC	BCL2	↓BCL-2→↑BAX	↑Apoptosis; ↓Migration; ↓Mammosphere formation; ↓Tumor growth	32319481	Ahir et al., 2020 [54]
miR-224	(+)TNBC	CASP9	↓Caspase-9	↓Apoptosis; ↑Proliferation; ↑Migration; ↑Invasion	30886656	Zhang et al., 2019 [60]
miR-125a/miR-181a	(-)TNBC	BCL2	↓BCL-2→↑BAX	↑Phospho-p53; ↑PARP cleavage; ↑Apoptosis	31541355	Majzoub et al., 2019
miR-20b	(-)TNBC	VEGF	↓BCL-2→↑BAX; →Caspase-9/3	↑Apoptosis; ↓Proliferation; ↓Migration; ↓Invasion	28550685	Lu et al., 2018 [59]
miR-15/16	(-)TNBC	BMI1	↓BCL-2/↑BAX/↑BID; →↓ΔΨm→↑caspase-9/3	↑Cell death; ↓Proliferation; ↓Migration	27596816	Patel et al., 2016 [58]
miR-223	(-)TNBC	HAX1	↓HAX-1	↑TRAIL-induced apoptosis of TNBCSC	27618431	Sun et al., 2016 [57]
miR-145	(-)TNBC	cIAP	↓cIAP→↑FADD→; ↑Caspase-8/3→↑tBID	↑TNF-α-induced apoptosis	26733177	Zheng et al., 2016 [56]
miR-101	(-)TNBC	MCL1	↓MCL-1→↓ΔΨm	↑Apoptosis; ↓Proliferation; ↓Tumor growth; ↑TNBC sensitivity to paclitaxel	26036638	Liu et al., 2015 [55]

2-DG: 2-deoxy-D-glucose; ΔΨm: mitochondrial membrane potential; BAX: Bcl-2-associated X protein; BCL-2: B cell lymphoma 2; BID: BH3 interacting-domain death agonist; CASP9: caspase-9; cIAP: cellular inhibitor of apoptosis; FADD: Fas-associated protein with death domain; HAX-1: HCLS1-associated protein X-1; MCL-1: induced myeloid leukemia cell differentiation protein Mcl-1; PARP: poly ADP-ribose polymerase; tBID: truncated BH3 interacting-domain death agonist; TRAIL: tumor necrosis factor-related apoptosis-inducing ligand; TNBCSC: triple-negative breast cancer stem cell; VEGF: vascular endothelial growth factor.