Rosa Marilin, Han Hyo Sook, Ismail-Khan Roohi, Allam-Nandyala Pushpa, Bui Marilyn M
Departments of Anatomic Pathology and Women's Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA
Women's Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA.
Ann Clin Lab Sci. 2015 Winter;45(1):10-6.
β-catenin is a critical component of the cadherin cell-to-cell adhesion pathway and a key participant in the Wnt signaling pathway. Activation of β-catenin signaling in the Wnt pathway is a known contributor to tumor cancer progression and metastasis and may result in resistance to chemotherapeutic agents. The aim of this study is to evaluate the patterns of expression of β-catenin in breast carcinoma cells before and after neoadjuvant chemotherapy. Discovery of the molecular mechanisms responsible for resistance to chemotherapy treatment could result in more effective therapy, and improve outcome and survival.
Twenty-nine matched pre-treatment and post-neoadjuvant chemotherapy breast carcinomas were subjected to immunohistochemical study using anti-β-catenin antibody. Normal staining was defined as crisp membrane staining in >90% tumor cells; aberrant expression was nuclear staining in >5% tumor cells.
Of the 29 included cases, five cases of invasive lobular carcinoma lacked β-catenin immunoreactivity pre- and post-treatment. Mildly reduced membranous staining was seen in two post-treatment samples. One case of triple-negative ductal carcinoma had reduced pre- and post-treatment staining. All other cases showed normal pre- and post-treatment β-catenin expression. No aberrant staining was identified.
In our study, there was no difference in the expression of β-catenin in pre- and post-neoadjuvant chemotherapy specimens. These results do not suggest that β-catenin plays a role in conferring neoadjuvant chemotherapy resistance.
β-连环蛋白是钙黏蛋白细胞间黏附途径的关键组成部分，也是Wnt信号通路的关键参与者。Wnt通路中β-连环蛋白信号的激活是肿瘤进展和转移的已知因素，可能导致对化疗药物产生耐药性。本研究的目的是评估新辅助化疗前后乳腺癌细胞中β-连环蛋白的表达模式。发现化疗耐药的分子机制可能带来更有效的治疗方法，并改善治疗结果和生存率。
使用抗β-连环蛋白抗体对29例新辅助化疗前后配对的乳腺癌进行免疫组织化学研究。正常染色定义为超过90%的肿瘤细胞出现清晰的膜染色；异常表达定义为超过5%的肿瘤细胞出现核染色。
在纳入的29例病例中，5例浸润性小叶癌治疗前后均缺乏β-连环蛋白免疫反应性。2例治疗后的样本中可见轻度降低的膜染色。1例三阴性导管癌治疗前后染色均减少。所有其他病例治疗前后β-连环蛋白表达均正常。未发现异常染色。
在我们的研究中，新辅助化疗前后标本中β-连环蛋白的表达没有差异。这些结果并不表明β-连环蛋白在赋予新辅助化疗耐药性方面起作用。
