Evaluation of estrogen receptor alpha and beta and progesterone receptor expression and correlation with clinicopathologic factors and proliferative marker Ki-67 in breast cancers.
To elucidate the molecular profile of hormonal steroid receptor status, we analyzed ER-alpha, ER-beta, and PGR mRNA and protein expression in 80 breast carcinomas using reverse transcriptase polymerase chain reaction (RT-PCR), quantitative RT-PCR, and immunohistochemical analysis. Qualitative analysis revealed positive expression of ER-alpha, ER-beta, and PGR mRNA in 48%, 59%, and 48% of the breast carcinomas, respectively. ER-alpha, ER-beta, and PGR transcript overexpression was observed in 51%, 0%, and 12% of the cases, respectively, whereas moderate or strong protein expression was detected in 68%, 78%, and 49% of the cases, respectively. Tumor grade was negatively correlated with transcript and protein levels of ER-alpha (P = .0169 and P = .0006, respectively) and PGR (P = .0034 and P = .0005, respectively). Similarly, proliferative index Ki-67 was negatively associated with transcript and protein levels of ER-alpha (P = .0006 and P < .0001, respectively) and PGR (P = .0258 and P = .0005, respectively). These findings suggest that ER-alpha and PGR expression are associated with well-differentiated breast tumors and less directly related to cell proliferation. A significant statistical difference was observed between lymph node status and ER-beta protein expression (P = .0208). In ER-alpha-negative tumors, we detected a correlation between ER-beta protein expression and high levels of Ki-67. These data suggest that ER-beta could be a prognostic marker in human breast cancer.
Rosa
Fabíola E
FE
Department of Genetics, Institute of Biosciences, UNESP-São Paulo State University, 18618-000 Botucatu, São Paulo, Brazil.
Caldeira
José R F
JR
Felipes
Joice
J
Bertonha
Fernanda B
FB
Quevedo
Francisco C
FC
Domingues
Maria A C
MA
Moraes Neto
Francisco A
FA
Rogatto
Silvia R
SR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology* / Q000503:physiopathology*; D047628:Estrogen Receptor alpha / Q000378:metabolism*; D047629:Estrogen Receptor beta / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008875:Middle Aged; D011379:Prognosis; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D019394:Ki-67 Antigen; D012333:RNA, Messenger