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Seidah, N.

Publications and source records attributed to Seidah, N..

2 recordsLinked to original sources

Myostatin is a major endocrine driver of follicle-stimulating hormone synthesis

Myostatin is a paracrine myokine that regulates muscle mass in a variety of species, including humans. Here, we report a functional role for myostatin as an endocrine hormone directly promoting pituitary follicle-stimulating hormone (FSH) synthesis and thereby ovarian function. Previously, this FSH-stimulating role was attributed to other members of the transforming growth factor {beta} family, the activins. The results both challenge activins eponymous role in FSH synthesis and establish an endocrine axis between skeletal muscle and the pituitary gland. The data also suggest that efforts to antagonize myostatin to treat muscle wasting disorders may have unintended consequences on fertility. One-Sentence SummaryHormone synthesis and reproduction depend on crosstalk between skeletal muscle and the pituitary gland.

physiology↗

Inhibition of proprotein convertase subtilisin-like kexin type 9 (PCSK9) potentiates anti-angiogenic therapy in colorectal cancer liver metastases

Colorectal cancer liver metastatic (CRCLM) tumours present as two main histopathological growth patterns (HGPs) including desmoplastic HGP (DHGP) and replacement HGP (RHGP). The DHGP tumours obtain their blood supply by sprouting angiogenesis, whereas the RHGP tumours utilize an alternative vascularisation known as vessel co-option. In vessel co-option, the cancer cells hijack the mature sinusoidal vessels to obtain blood supply. Vessel co-option has been reported as an acquired mechanism of resistance to anti-angiogenic treatment in CRCLM. Herein, we showed that inhibiting proprotein convertase subtilisin-like kexin type 9 (PCSK9) via clinically approved PCSK9-neutralizing antibody (Evolocumab) can boost the response of vessel co-opting tumours to anti-angiogenic therapy. Mechanistically, we found that PCSK9 inhibition downregulates runt related transcription factor-1 (RUNX1) expression levels in CRCLM cancer cells in vivo, which its expression positively correlates with the development of vessel co-option. Collectively, these results suggest that inhibiting PCSK9 is a promising way to improve the efficacy of anti-angiogenic therapy against vessel co-opting tumours in CRCLM.

molecular biology↗