title: Downregulation of pancreatic-duodenal homeobox 1 expression in breast cancer patients: a mechanism of proliferation and apoptosis in cancer.
abstract: Pancreatic-duodenal homeobox 1 (PDX-1) is a transcription factor that regulates             embryological pancreas development and insulin expression in adult islets. The             current study investigated the expression profile and potential role of PDX-1             in breast cancer. Immunohistochemistry was performed to determine the expression             pattern of PDX-1 in breast cancer and adjacent benign breast tissues. In addition,             cell proliferation and the cell cycle were evaluated following the transient inhibition             of PDX-1 with antisense oligonucleotides in MCF-7 human breast cancer cells. Real-time             PCR and western blotting were conducted to investigate the correlation between             PDX-1, P53, Ki-67, Caspase 3 and Caspase 8. These experiments demonstrated that             PDX-1 was downregulated in human breast cancer tissue compared with adjacent normal             breast tissue. Knockdown of PDX-1 expression in vitro in MCF-7 breast cancer cells             promoted cell proliferation and disrupted the cell cycle, as demonstrated by the             overexpression of P53 and Ki-67 at the mRNA and protein levels. In conclusion,             the current study shows that PDX-1 regulates cell proliferation and the cell cycle             in human breast cancer cells by altering the expression of the cell cycle-related             genes, P53 and Ki-67. These data suggest that PDX-1 is a putative tumor suppressor             in breast cancer.
authors.affiliation: Department of Breast and Thyroid Surgery, Tenth People's Hospital of Tongji University, Zhabei, Shanghai 200072, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.forename: Hua
authors.initials: H
authors.lastname: Li
authors.forename: Xigang
authors.initials: X
authors.lastname: Xiao
authors.forename: Lei
authors.initials: L
authors.lastname: Shen
authors.forename: Lin
authors.initials: L
authors.lastname: Fang
mesh_terms: D017209:Apoptosis; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D049109:Cell Proliferation; D015536:Down-Regulation; D005260:Female; D059585:G1 Phase Cell Cycle Checkpoints; D055785:Gene Knockdown Techniques; D018398:Homeodomain Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000235:genetics / Q000378:metabolism; D061986:MCF-7 Cells; D008875:Middle Aged; D009367:Neoplasm Staging; D016376:Oligonucleotides, Antisense / Q000378:metabolism; D015534:Trans-Activators / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D018398:Homeodomain Proteins; D019394:Ki-67 Antigen; D016376:Oligonucleotides, Antisense; D015534:Trans-Activators; D016159:Tumor Suppressor Protein p53; C084010:pancreatic and duodenal homeobox 1 protein; D053148:Caspase 3; D053181:Caspase 8