Background: Pancreatic ductal adenocarcinoma (PDAC) is among the most common causes of cancer death. Preclinical and clinical studies on the preventive effects of beta-carotene or other retinoids have used dietary supplements that yielded high systemic concentrations (1-50 microM). While some of the preclinical data suggested cancer preventive effects of these agents, they have disappointed in clinical investigations.
Materials And Methods: The effects of low concentrations (10 fM-200 nM)of beta-carotene on the proliferation, intracellular cAMP levels, PKA activation status and phosphorylation of EGFR-specific tyrosine kinases and ERK1/2 in immortalized human pancreatic duct epithelial cells was investigated.
Results: Our data show significant concentration-dependent and PKA-dependent stimulation of all measured endpoints. Similar responses were achieved with forskolin. Our data indicate that low concentrations of beta-carotene stimulate the proliferation of the putative origin of PDAC, pancreatic duct epithelial cells via cAMP and PKA-dependent transactivation of the EGFR pathway. This could potentially have promoting effects on the development of PDAC.
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Domest Anim Endocrinol
January 2025
BIOFITER-IUCA, Universidad de Zaragoza, Facultad de Veterinaria, Miguel Servet 177, 50013 Zaragoza, Spain. Electronic address:
This review presents recent findings on the effect of melatonin on ram spermatozoa. This hormone regulates seasonal reproduction in the ovine species through the hypothalamic-pituitary-gonadal axis, but it also exerts direct effects on spermatogenesis, seminal quality and fertility. In the testis, melatonin stimulates blood flow to this organ, but it also appears to be involved in the differentiation of spermatogonial stem cells and the secretion of testosterone through the MT1 and MT2 receptors.
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Research Center for Water Resources and Interface Science, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.
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Center of Gene Sequencing, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, P. R. China.
FBXW7 is a tumor suppressor gene that regulates metabolism and is associated with the onset and progression of colorectal cancer (CRC)), however, the precise mechanism whereby FBXW7 participates in the metabolic reprogramming of CRC remains unclear. Here, the research aims to reveal the association between the expression of FBXW7 and clinical variables and to investigate the molecular mechanism by which FBXW7 plays a critical role in the development of CRC. The clinical importance of FBXW7 in CRC was determined by immunohistochemistry.
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Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China.
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