Associations Between The Nuclear Expression Of DJ-1/Park7 And Clinicopathologic Parameters Of Human Invasive Breast Carcinomas

Objective: DJ-1/park7 is a cancer- and Parkinson’s disease-associated protein which has been implicated in various aspects of transformation in human tumors. This aim of this study is to evaluate the relationship between nuclear expression of DJ-1/park7 in Chinese invasive breast carcinomas and clinicopathologic parameters.Methods: We assessed 258 cases of invasive breast carcinomas including 153 invasive ductal carcinomas(IDCs), 41 pure mucinous carcinomas(PMCs), 33 invasive lobular carcinomas(ILCs) and 31 invasive micropapillary carcinomas(IMPCas) using formalin fixed, paraffin embedded tissues. Furthermore, we also investigated 17 gastric, 18 colorectal and 13 pulmonary adenocarcinomas and primary signet-ring cell carcinomas of 14 stomach, 13 colorectum and 2 lung to evaluate the expression pattern of DJ-1/park7 in mucin-producting carcinomas from other organs. We examined the expressions of DJ-1/park7 by immunohistochemistry.Results: DJ-1/park7 demonstrated cytoplasmic, membranous, apical, and combinative expressions. Nuclear Expression of DJ-1/park7 in invasive breast carcinomas was obviously down-regulated than that in normal mammary gland, except inmucinous carcinoma. DJ-1/park7 nuclear expression was correlated with better histological grade(P = 0.002). DJ-1/park7 nuclear expression was associated with lower Ki-67 index(P=0.002), higher ER(P=0.001) and PR expression(P=0.005) while negative DJ-1/park7 nuclear expression was associated with triple negativity and HER2 negativity. What was more interesting was that the nuclear expression of DJ-1/park7 in mucinous carcinoma was always 6-fold higher than that in adjacent normal gland, regardless of histological origin.The protein nuclear levels of signet-ring cell carcinomas were all higher than those of corresponding normal tissue and lower than those of corresponding mucinous carcinoma.Conclusions: DJ-1/park7 nuclear expression is correlated with some clinicopathologic parameters that are indicators of better prognosis in invasiveductalcarcinomas of breast. Nuclear location of DJ-1/park7 plays a potential role in secretion of mucin.To evaluate the role of DJ-1/park7 as a potential biomarker, further studies are warranted.