RESUMEN
Vitamin D receptor (VDR) gene polymorphisms have been reported to influence susceptibility to breast cancer. However, published findings on the association between VDR Cdx2 polymorphism and breast cancer susceptibility are conflicting. To get a precise estimation of the association between VDR Cdx2 polymorphism and breast cancer susceptibility, we conducted a meta-analysis of four case-control studies with a total of 8,880 subjects (3,841 cases and 5,039 controls). The results showed that VDR Cdx2 polymorphism was not associated with risk of breast cancer (A versus G: OR = 0.96, 95% CI 0.84-1.09; AA versus GG: OR = 0.97, 95% CI 0.64-1.45; AA/GA versus GG: OR = 0.94, 95% CI 0.80-1.10; AA versus GG/GA: OR = 0.99, 95% CI 0.65-1.51). Subgroup analysis in Caucasians also showed that VDR Cdx2 polymorphism was not associated with risk of breast cancer in Caucasians. However, there was a significant association in Africans (A versus G: OR = 0.75, 95% CI 0.60-0.94; AA versus GG: OR = 0.53, 95% CI 0.29-0.99; AA/GA versus GG: OR = 0.75, 95% CI 0.57-0.97). Therefore, the association between VDR Cdx2 polymorphism and breast cancer susceptibility is only found in Africans. More studies are needed to further assess the association in Asians or Africans.
Asunto(s)
Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple , Receptores de Calcitriol/genética , Sitios de Unión/genética , Población Negra/genética , Neoplasias de la Mama/etnología , Factor de Transcripción CDX2 , Estudios de Casos y Controles , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/etnología , Genotipo , Proteínas de Homeodominio/metabolismo , Humanos , Oportunidad Relativa , Transactivadores/metabolismo , Población Blanca/genéticaRESUMEN
Notch2, a surface marker in cell lines, is used to isolate, identify and localise pancreatic cancer stem-like cells and is a target for therapy of these cells. Sphere formation was induced in Panc-1 and Bxpc-3 pancreatic cancer cell lines, and Notch2(+) cells were separated from Bxpc-3 and Panc-1 cell lines by magnetic activated cell sorting (MACS). Expression of stem cell-related markers, OCT4, Nanog and PDX1, were measured by immunofluorescent (IF) staining. Expression of Notch2 was also determined immunohistochemically in pancreatic tissues. Notch2(+) cells were transplanted in subcutaneous of mice. AQP1 and AQP5 were also measured by IF in Bxpc-3 cells. The Notch signal pathway inhibitor, Compound E (CE), was used to treat Notch2(+) Bxpc-3 cells, and their vitalities were subsequently measured by the CCK-8 method. Positive expression of OCT4, Nanog and PDX1 was observed in Notch2(+) cells. Notch2(+) cells at centroacinar cell (CAC) and terminal ductal locations expressed AQP1 and AQP5. They were strongly tumourigenic in mice, and CE inhibited proliferation of Notch2(+) Bxpc-3 cells to some degree. OCT4 and Nanog can be used as markers of self-renewal in pancreatic cancer stem cells. Notch2(+) cells in human pancreatic cancer Bxpc-3 and Panc-1 cell lines had the properties of cancer stem cells. The results suggest that Notch2(+) pancreatic cancer stem-like cells had a close relationship with CAC.
