The novel role of miRNAs for tamoxifen resistance in human breast cancer

Abstract

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Tamoxifen Resistance: Emerging Molecular Targets

“…In addition, recent studies in ERα-positive cell lines have shown that restoring certain miRNAs sensitized these cells to TAM. Such miRNAs include miR-342 [201], miR-375 [202], miR-451 [203], miR-261, miR-575 [204], miR-200b and miR-200c [205,206] (Figure 8). …”

“…Recent studies have focused on drugs targeting nucleic acids in order to develop breast cancer therapies, with the objectives centering on either inactivating ncRNAs, which confer resistance to TAM, or enhancing the effect of ncRNAs that restore susceptibility to anti-estrogen treatment [206,234,235]. These emerging therapies include ribozymes, siRNAs, antisense oligonucleotides (ASOs) or their chemically tailored analogs (known as locked nucleic acids, LNAs), which can alter RNA splicing and induce degradation of the targeted RNA via RNaseH.…”

“…Such approaches can inhibit the production of an endogenous miRNA, while synthetic or miRNA mimics can be used to treat a deficiency in miRNA expression. Similar methodologies can also be employed to modulate the production of lncRNAs in order to enhance sensitivity to TAM [206,236,237]. …”

Targeting ceramide metabolic pathway induces apoptosis in human breast cancer cell lines

“…However, its significance over cell proliferation has also been reported in ER À breast cancer cells indicating its ER independent effect [4]. Eventhough, Tamoxifen has been approved to be the gold standard for Breast cancer therapy the major problem encountered with Tamoxifen is resistance after long term treatment [5,6].…”

Preclinical characterization of SHR6390, a novel CDK 4/6 inhibitor, in vitro and in human tumor xenograft models

“…Approximately 70% of human breast cancers present as ER‐positive, a cancer cell subtype that requires estrogen for survival and growth. Endocrine therapy including tamoxifen, fulvestrant and letrozole is currently recognized as the most effective and clearly targeted form of adjuvant therapy for hormone‐sensitive breast cancer . However, the prevalence of primary and acquired resistance severely restricts the efficacy of these agents in the clinic, and the development of new treatments for breast cancer is a research priority.…”