The miR-200 family in normal mammary gland development

Abstract

The miR-200 family of microRNAs plays a significant role in inhibiting mammary tumor growth and progression, and its members are being investigated as therapeutic targets. Additionally, if future studies can prove that miR-200s prevent mammary tumor initiation, the microRNA family could also offer a preventative strategy. Before utilizing miR-200s in a therapeutic setting, understanding how they regulate normal mammary development is necessary. No studies investigating the role of miR-200s in embryonic ductal development could be found, and only two studies examined the impact of miR-200s on pubertal ductal morphogenesis. These studies showed that miR-200s are expressed at low levels in virgin mammary glands, and elevated expression of miR-200s have the potential to impair ductal morphogenesis. In contrast to virgin mammary glands, miR-200s are expressed at high levels in mammary glands during late pregnancy and lactation. miR-200s are also found in the milk of several mammalian species, including humans. However, the relevance of miR-200s in milk remains unclear. The increase in miR-200 expression in late pregnancy and lactation suggests a role for miR-200s in the development of alveoli and/or regulating milk production. Therefore, studies investigating the consequence of miR-200 overexpression or knockdown are needed to identify the function of miR-200s in alveolar development and lactation.

Adipo-Epithelial Transdifferentiation in In Vitro Models of the Mammary Gland

“…In fact, adding TGFβ to epithelial cells in culture is a convenient way to induce EMT in various epithelial cells [ 49 ]. Lastly, these data are in line with the high levels of mir200 in late stages of pregnancy in mice [ 50 ].…”

Tumor microenvironment of cancer stem cells: Perspectives on cancer stem cell targeting

“… 256 They play a significant role in inhibiting mammary tumor growth and progression, and their members are being investigated as therapeutic targets. 257 It was also confirmed that miR-200 could suppress the self-renewal and differentiation of CSCs, regulate cell division and apoptosis, and reverse chemotherapy resistance. 258 Additionally, Let7d has been shown to be down-regulated in osteosarcoma CSCs and decrease their sphere- and colony-forming ability.…”

MiRNome variations in milk fractions during feed restrictions of different intensities in dairy cows

“…The abundance of bta-let-7g-5p increased in EV during H feed restriction (FC = 1.19; P = 0.01); the inhibition role of this miRNA on β-casein protein synthesis and MEC differentiation has also been reported in a mouse model [ 32 ]. Finally, miR-200c-3p , whose abundance increased in EV during H feed restriction (FC = 1.32; P = 0.04), is a member of the miR-200 family and is thus known for its effect on mammary gland morphogenesis [ 33 ]. Its lower abundance during feed restriction was consistent with the reorganization of mammary gland tissue (which could lead to mammary gland involution) that has been observed during an intense feed restriction experiment [ 34 ].…”