Expression of aldehyde dehydrogenase after neoadjuvant chemotherapy is associated with expression of hypoxia-inducible factors 1 and 2 alpha and predicts prognosis in locally advanced breast cancer

OBJECTIVE: To analyze the expression of hypoxia-inducible factors (hypoxia-inducible factor 1A and hypoxia-inducible factor 2A) and aldehyde dehydrogenase proteins in patients with locally advanced breast carcinoma who were subjected to neoadjuvant chemotherapy. METHODS: We included 90 patients with histologically confirmed stage II and III breast carcinoma who were treated with neoadjuvant chemotherapy between 2000 and 2005. Immunohistochemistry for aldehyde dehydrogenase, hypoxia-inducible factor 1A, and hypoxia-inducible factor 2A was performed before and after neoadjuvant chemotherapy. We analyzed the influence of clinical and pathological features on clinical and pathological response, disease-free survival, and overall survival. RESULTS: An objective clinical response to neoadjuvant chemotherapy was observed in 80% of patients, with 12% showing a complete pathological response. Among all clinical and pathological parameters, only the expression of hypoxia-inducible factor 1A was associated with a pathological response. A positive association was found between expression of aldehyde dehydrogenase and that of hypoxia-inducible factor 1A before and after chemotherapy. Aldehyde dehydrogenase expression was associated with expression of hypoxia inducible-factor 2A in tumors after neoadjuvant treatment. In a univariate analysis, prognosis was influenced by age, pathological response, metastasis to axillary lymph nodes after neoadjuvant chemotherapy, overexpression of hypoxia-inducible factor 2, and the presence of aldehyde dehydrogenase-positive cells within the primary tumor after neoadjuvant chemotherapy. In a multivariate analysis, only age and the presence of aldehyde dehydrogenase-positive cells after chemotherapy were associated with reduced overall survival. CONCLUSION: The presence of aldehyde dehydrogenase-positive cells within the residual tumor after neoadjuvant chemotherapy is associated with an increase in the expression of hypoxia-inducible factor 2A and with poor prognosis in patients with locally advanced breast cancer

Correlation of ALDH expression and enzyme function in breast cancer

A alta atividade da enzima Aldeído-desidrogenase (ALDH) tem sido relatada como um marcador das células troncos tumorais (CTT) no câncer de mama. Sabe-se que essas células estão envolvidas na resistência ao tratamento radio e quimioterápico e podem ser responsáveis pela recorrência e disseminação metastática. A associação entre a quantidade de CTTs e a resposta a quimioterapia neoadjuvante (QNA) ainda não está estabelecida. Foi analisado retrospectivamente a expressão de ALDH1A1 por imunohistoquímica (IHQ) em amostras previamente analisadas por citometria de fluxo para ALDH1A1 no tumor primário de 61 pacientes com carcinoma ductal invasivo diagnosticado entre 2010 e 2012. A maioria das pacientes estava entre 51-70 anos (59%), na menopausa (65,6%) e com estádio clínico III (47,5%). A expressão positiva de receptores de estrógeno, progesterona e de HER2 foi de 67,2%, 52,5% e 45,9% respectivamente. A imunohistoquímica para ALDH1A1 foi realizada com lâminas da TMA e considerado positivos os casos com marcação citoplástica evidente em grupamentos de 5 ou mais células. Foi analisada a associação entre esses dados e o resultado da citometria de fluxo para ALDH1 e também a associação com os fatores prognósticos conhecidos. Não foi encontrada associação (p = 0,67) entre a porcentagem de células ALDH1+ com o resultado da imunohistoquímica positiva para ALDH1A1 (4,45% (1,7 - 10,1)) e negativa (3,2% (1,2 - 13,6)). Os dados não demonstraram associação da IHQ para ALDH1A1 ou da quantia de células ALDH1+ no tumor primário com a resposta patológica completa após quimioterapia neoadjuvante, sugerindo que essa população pode não ser um fator preditor isolado da resposta a QNA. Também não foi observado relação da IHQ para ALDH1A1 com os fatores prognósticos conhecidos. A sobrevida também não foi influenciada pela expressão de ALDH1A1 pela IHQ tanto na sobrevida global (p = 0,54; HR = 1,33 (0,52 - 3,39)) quanto na livre de doença (p = 0,35; HR = 1,67 (0,57 - 4,90)). Quanto a porcentagem de células ALDH1+ no tumor primário, também não houve impacto sobre a sobrevida global (p = 0,40; HR = 0,98 (0,92 - 1,03)), nem na sobrevida livre de doença (p = 0,55; HR = 0,98 (0,92 - 1,05)). A presença de células ALDH1A1 positivas na imunohistoquímica não se relaciona com a atividade da enzima analisada por citometria de fluxo e não apresenta associação com fatores prognósticosThe expressions of aldehyde-dehydrogenase (ALDH) has been reported as potential breast cancer stem-like cells (BCSLCs) markers. Those cells are known to be involved with treatment resistance and may be responsible for relapses and metastatic dissemination. The association between the quantity of BCSLCs and the response to neoadjuvant chemotherapy (NACT) remains unclear. We retrospectively analyzed the expression of ALDH1A1 by immunohistochemistry (IHQ) in 61 patients with invasive ductal carcinomas of the breast from 2010 to 2012 previously analyzed by flow cytometry (FCT). Most patients were aged between 51-70 years (59%), clinical stage III (47,5%) and menopausal (65,6%). The ER, PgR and HER2 positive expression rates were 67,2%, 52,5% and 45,9%, respectively. The aldehyde-dehydrogenase immunohistochemistry ware evaluated by TMA and considered to be positive cases with evident cytoplasmic staining in clusters of 5 or more cells. These data were correlated with the flow cytometry results and clinical and pathological features. No association between ALDH1+ cell population by FCT with ALDH1A1 positive (4,45% (1,7 - 10,1)) and negative (3,2% (1,2 - 13,6)) cases by IHQ were observed (p= 0,67). No relationship between ALDH1A1+ by IHQ nor ALDH1+ by FCT were found with the complete pathological response to therapy, suggesting that it might not be an isolated predictor of response to NACT. No relationship between IHQ was found with the clinicalpathological features. The overall survival was the same between the two groups by IHQ (p = 0,54; HR = 1,33 (0,52 - 3,39)) and also the disease free survival (p = 0,35; HR = 1,67 (0,57 - 4,90)). The FCT results did not correlate with the overall survival (p = 0,40; HR = 0,98 (0,92 - 1,03)), nor with the disease free survival (p = 0,55; HR = 0,98 (0,92 - 1,05)). The expression of ALDH1A1+ by immunohistochemistry have no association with the enzymatic function analyzed by flow cytometry and do not represent a prognostic facto

Expression of aldehyde dehydrogenase after neoadjuvant chemotherapy is associated with expression of hypoxia-inducible factors 1 and 2 alpha and predicts prognosis in locally advanced breast cancer

OBJECTIVE: To analyze the expression of hypoxia-inducible factors (hypoxia-inducible factor 1A and hypoxia-inducible factor 2A) and aldehyde dehydrogenase proteins in patients with locally advanced breast carcinoma who were subjected to neoadjuvant chemotherapy. METHODS: We included 90 patients with histologically confirmed stage II and III breast carcinoma who were treated with neoadjuvant chemotherapy between 2000 and 2005. Immunohistochemistry for aldehyde dehydrogenase, hypoxia-inducible factor 1A, and hypoxia-inducible factor 2A was performed before and after neoadjuvant chemotherapy. We analyzed the influence of clinical and pathological features on clinical and pathological response, disease-free survival, and overall survival. RESULTS: An objective clinical response to neoadjuvant chemotherapy was observed in 80% of patients, with 12% showing a complete pathological response. Among all clinical and pathological parameters, only the expression of hypoxia-inducible factor 1A was associated with a pathological response. A positive association was found between expression of aldehyde dehydrogenase and that of hypoxia-inducible factor 1A before and after chemotherapy. Aldehyde dehydrogenase expression was associated with expression of hypoxia inducible-factor 2A in tumors after neoadjuvant treatment. In a univariate analysis, prognosis was influenced by age, pathological response, metastasis to axillary lymph nodes after neoadjuvant chemotherapy, overexpression of hypoxia-inducible factor 2, and the presence of aldehyde dehydrogenase-positive cells within the primary tumor after neoadjuvant chemotherapy. In a multivariate analysis, only age and the presence of aldehyde dehydrogenase-positive cells after chemotherapy were associated with reduced overall survival. CONCLUSION: The presence of aldehyde dehydrogenase-positive cells within the residual tumor after neoadjuvant chemotherapy is associated with an increase in the expression of hypoxia-inducible factor 2A and with poor prognosis in patients with locally advanced breast cancer