Immunohistochemical expression of RARalpha, RARbeta, and Cx43 in breast tumor cell lines after treatment with lycopene and correlation with RT-QPCR

International audienceLe lycopène, le principal caroténoïde présent dans les tomates, est un puissant antioxydant associé à la prévention de maladies dégénératives telles que le cancer du sein. Cet effet pourrait être dû à l'interaction entre les récepteurs du lycopène et de l'acide rétinoïque ainsi qu'à la stimulation de la communication par jonction lacunaire et de la synthèse de la connexine 43. L'expression des protéines RARalpha, RARbeta et Cx43 a été analysée par immunohistochimie dans deux lignées cellulaires de cancer du sein. , MCF-7 et MDA-MB-231, et dans une lignée cellulaire de dystrophie fibrokystique, MCF-10a, après une exposition de 48 heures à 10 μM de lycopène. Une analyse PCR quantitative en temps réel a ensuite été effectuée pour mesurer l'expression de l'ARNm. L'expression de RARalpha et de Cx43 a été augmentée aux niveaux d'ARNm et de protéines dans deux lignées de cellules mammaires

Differential expressions of BRCA1 and BRCA2 in infantile gynecomastia.

International audienceBRCA1 and BRCA2 breast cancer susceptibility genes are responsible for most of the hereditary breast cancers. No or very few sporadic breast tumors have been shown to harbor mutations in the coding sequence of BRCA1 or BRCA2. In contrast to normal breast epithelial cells, BRCA1 mRNA levels in tumors appeared to be down-regulated by methylation, while BRCA2 showed significant overexpression in sporadic breast cancers. We report herein an infantile gynecomastia in a two-year-old boy, studied by immunohistochemistry of anti-BRCA1 and anti-BRCA2 antibodies. We demonstrated that BRCA1 proteins, like BRCA2, are widely expressed in the nuclei of epithelial cells surrounding the lumen of the ducts in infantile gynecomastia. The intensive nuclear staining of both proteins in the mammary tissues means that BRCA1 and BRCA2 proteins are largely expressed in infantile gynecomastia

Presence of BRCA1 and BRCA2 proteins in human milk fat globules after delivery.

International audienceWe evaluated BRCA1 and BRCA2 oncosuppressor protein expression in 26 milk samples in women just after delivery. The quantification of BRCA1 and BRCA2 proteins was performed in isolated milk fat globules using an affinity chromatography strategy. The amounts of BRCA1 and BRCA2 proteins were found to be similar. We explained the presence of BRCA1 and BRCA2 proteins in human milk fat globules by the fact that they are formed by exocytosis of lipids from epithelial cells of the mammary gland and are enveloped by plasma membrane from the apical part of the milk-secreting cells. This raises the possibility that BRCA1 and BRCA2 proteins are a protective response to proliferation and play a possible role in newborn nutrition

Presence of BRCA1 and BRCA2 proteins in human milk fat globules after delivery.

International audienceWe evaluated BRCA1 and BRCA2 oncosuppressor protein expression in 26 milk samples in women just after delivery. The quantification of BRCA1 and BRCA2 proteins was performed in isolated milk fat globules using an affinity chromatography strategy. The amounts of BRCA1 and BRCA2 proteins were found to be similar. We explained the presence of BRCA1 and BRCA2 proteins in human milk fat globules by the fact that they are formed by exocytosis of lipids from epithelial cells of the mammary gland and are enveloped by plasma membrane from the apical part of the milk-secreting cells. This raises the possibility that BRCA1 and BRCA2 proteins are a protective response to proliferation and play a possible role in newborn nutrition