title: Vitamin D suppresses leptin stimulation of cancer growth through microRNA.
abstract: Obesity is a pandemic and major risk factor for cancers. The reduction of obesity would have been an effective strategy for cancer prevention, but the reality is that worldwide obesity has kept increasing for decades, remaining a major avoidable cancer risk secondary only to smoke. The present studies suggest that vitamin D may be an effective agent to reduce obesity-associated cancer risks in women. Molecular analyses showed that leptin increased human telomerase reverse transcriptase (hTERT) mRNA expression and cell growth through estrogen receptor-α (ERα) activation in ovarian cancer cells, which was suppressed by 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3]. The suppression was compromised when miR-498 induction by the hormone was depleted with microRNA (miRNA) sponges. In mice, high-fat diet (HFD) stimulation of ovarian tumor growth was remarkably suppressed by 1,25(OH)2D3 analogue EB1089, which was also compromised by miR-498 sponges. EB1089 did not alter HFD-induced increase in serum leptin levels but increased miR-498 and decreased the diet-induced hTERT expression in tumors. Quantitative RT-PCR analyses revealed an inverse correlation between hTERT mRNA and miR-498 in response to 1,25(OH)2D3 in estrogen-sensitive ovarian, endometrial, and breast cancers. The studies suggest that miR-498-mediated hTERT downregulation is a key event mediating the anti-leptin activity of 1,25(OH)2D3 in estrogen-sensitive tumors in women.
authors.affiliation: Department of Pathology and Cell Biology, University of South Florida College of Medicine, Tampa, Florida.
authors.forename: Ravi
authors.initials: R
authors.lastname: Kasiappan
authors.affiliation: Department of Pathology and Cell Biology, University of South Florida College of Medicine, Tampa, Florida.
authors.forename: Yuefeng
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Pathology and Cell Biology, University of South Florida College of Medicine, Tampa, Florida.
authors.forename: Panida
authors.initials: P
authors.lastname: Lungchukiet
authors.affiliation: Department of Pathology and Cell Biology, University of South Florida College of Medicine, Tampa, Florida.
authors.forename: Waise
authors.initials: W
authors.lastname: Quarni
authors.affiliation: Department of Pathology and Cell Biology, University of South Florida College of Medicine, Tampa, Florida. Department of Oncological Sciences, University of South Florida College of Medicine, Tampa, Florida. Program of Cancer Biology and Evolution, H. Lee Moffitt Cancer Center, Tampa, Florida.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pathology and Cell Biology, University of South Florida College of Medicine, Tampa, Florida. Department of Oncological Sciences, University of South Florida College of Medicine, Tampa, Florida. Program of Cancer Biology and Evolution, H. Lee Moffitt Cancer Center, Tampa, Florida. wbai@health.usf.edu.
authors.forename: Wenlong
authors.initials: W
authors.lastname: Bai
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D059305:Diet, High-Fat; D047628:Estrogen Receptor alpha / Q000096:biosynthesis / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D020738:Leptin / Q000096:biosynthesis* / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D010051:Ovarian Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D019098:Telomerase / Q000096:biosynthesis / Q000235:genetics; D014807:Vitamin D / Q000008:administration & dosage
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D020738:Leptin; C578093:MIRN498 microRNA, human; D035683:MicroRNAs; D014807:Vitamin D; C509186:TERT protein, human; D019098:Telomerase