Relationship between Expression of Runt-related Transcription Factor 3 and Enhancer of zeste Homolog 2 Proteins and Sensitivity to Neoadjuvant Chemotherapy in Locally Advanced Rectal Cancer / 中国医学科学院学报

Objective To investigate the expression and correlation of Runt-related transcription factor 3(RUNX3)and enhancer of zeste homolog 2(EZH2)in rectal cancer,and to reveal the relationship between the expression of RUNX3 and EZH2 and the sensitivity of XELOX regimen to neoadjuvant chemotherapy in locally advanced rectal cancer patients. Methods The carcinoma and paracancerous tissues of 31 patients with rectal adenocarcinoma and no preoperative antitumor therapy were selected as cancer group and paracancer group,respectively.The relative mRNA levels of RUNX3 and EZH2 in the two groups were measured by real-time quantitative reverse transcription-polymerase chain reaction,and the protein levels were determined by immunohistochemical assay.The expression of RUNX3 and EZH2 was compared between cancer tissue and paracancerous tissue.The pre-treatment wax blocks of 26 patients with locally advanced rectal cancer who received 3 cycles of XELOX regimen as neoadjuvant chemotherapy before surgery were selected as the pre-neoadjuvant therapy group,and the postoperative pathological wax blocks were selected as the post-neoadjuvant treatment group.Tumor regression grade(TRG)was determined to evaluate the efficacy of neoadjuvant therapy.Immunohistochemical assay was used to detect the protein levels of RUNX3 and EZH2 in the two groups,and then the relationship between the expression patterns of the two proteins and the efficacy of neoadjuvant chemotherapy was analyzed. Results Compared with paracancerous tissue,the cancer tissue showed down-regulated mRNA level and reduced positive protein expression rate of RUNX3,while up-regulated mRNA level(

Research Progress of Expression and Clinical Significant of EZH2 in Hematological Malignancies--Review / 中国实验血液学杂志

Enhancer of zeste homolog 2(EZH2) is a histone methyltransferase which regulate gene expression through epigenetic machinery. The abnormal expression of EZH2 has been described in many cancer types. With in-depth study, it was found that EZH2 is involved in the occurrence and development in many kinds of malignant hematologic disease which may play a dual role of oncogenes and tumor suppressor genes. In recent years, the emergence of EZH2 inhibitors provide a new option for the future treatment of hematological malignancies. In this review, the expression and clinical significance of EZH2 in various of hematological tumors were summarized briefly.

EZH2 Protein Expression and Tumor Response to Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer / Expressão da proteína EZH2 e resposta tumoral à quimioterapia neoadjuvante no câncer de mama localmente avançado

Abstract Introduction Neoadjuvant chemotherapy (NAC) is the standard treatment for locally advanced breast cancer. However, some tumors will not respond to this treatment due to histological and molecular features. The protein EZH2 (enhancer of zest homolog 2) is a histone methyltransferase that is correlated with poorly differentiated breast carcinomas and aggressive tumor behavior. Purpose The present study evaluated the association between EZH2 expression and response to NAC, and its correlation with HER2 overexpression, estrogen and progesterone receptors (ER, PR) and Ki-67 proliferation index. Methods A total of 60 patients with locally advanced breast cancer treated with NAC were selected for this study. Twenty-three paraffin blocks had not enough material for tissue resection, and were not evaluated. A tissue microarray based in immunohistochemistry (IHC) analysis of EZH2 was performed for the remaining 37 specimens. Patients were divided into two groups based on response to NAC. Results EZH2 expression was significantly associated with markers of poor prognosis such as ER negativity (p = 0.001), PR negativity (p = 0.042) and high Ki-67 proliferation index (p = 0.002). High EZH2 expression was not correlated with the response to NAC. Conclusions Our data suggested that EZH2 protein expression may not correlate with the clinical response to NAC. Other studies with more patients are needed to confirm this observation.

Resumo Introdução A quimioterapia neoadjuvante é o tratamento padrão para os cânceres de mama localmente avançados. Entretanto, apenas uma porcentagem desses tumores irá responder ao tratamento, devido a características histológicas e moleculares. A proteína EZH2 (enhancer of zest homolog 2) é uma histona metiltransferase associada a tumores mal diferenciados e de comportamento agressivo. Objetivo O presente estudo teve como objetivo avaliar a associação entre a expressão da proteína EZH2 e a resposta à quimioterapia neoadjuvante, além da correlação dessa proteína com hiper-expressão de HER2, receptores de estrogênio e progesterona, e o marcador de proliferação Ki-67. Métodos Um total de 60 pacientes com câncer de mama localmente avançado tratadas com quimioterapia neoadjuvante foram selecionadas para esse estudo. Vinte e três blocos de parafina não continham material suficiente para ressecção e não foram avaliados. Foi realizado microarray baseado em análise imuno-histoquímica da proteína EZH2 para as 36 pacientes restantes. As pacientes foram divididas em dois grupos baseado na resposta à quimioterapia neoadjuvante. Resultados A expressão da proteína EZH2 foi significativamente associada com marcadores de pior prognóstico, como negatividade para receptor de estrogênio (p = 0,001) e progesterona (p = 0,042), além de alto Ki-67 (p = 0,002). Entretanto, a alta expressão da EZH2 não se correlacionou com a resposta à quimioterapia neoadjuvante. Conclusões Nossos dados sugerem que a expressão da proteína EZH2 pode não estar relacionada com a resposta clínica à quimioterapia neoadjuvante. Outros estudos com maior número de pacientes são necessários para confirmar esses achados.