Expression And Clinical Significance Of LRIG1 And EGFR In Invasive Breast Cancer

Objective:The aim of this study is to investigate the expressions of leucine-rich repeats and immunoglobulin-like domains 1(LRIG1) and epidermal growth factor receptor(EGFR) in invasive breast cancer and their correlation with clinical pathological features,patients’ prognosis,and to investigate the correlation of the two indicators in invasive breast cancer. Methods:The expressions of LRIG1 and EGFR were detected in 88 cases of invasive breast cancer tissues and 88 cases of the corresponding adjacent breast tissue by immunohistochemistry methods.The correlation between the expressions of LRIG1 and EGFR with age,the tumor size,TNM stages,the histological grade, the degree of axillary lymphatic metastasis,ER,PR,HER2, tumor molecular classifications and patients’ prognosis invasive were statistically analyzed. Additionally,the correlation of the expression between LRIG1 and EGFR in invasive breast cancer was also analyzed. Results:1. The positive rate of LRIG1 expression in invasive breast cancer tissues was 40.9%, which was significantly lower than that in normal pericarcinous breast tissues(80.7%, P<0.01). There was no significant correlation between the expression of LRIG1 and age, tumor size, clinical TNM stage(P>0.05). Statistical analysis showed that the histological grade was related with the expression of LRIG1 and there were significant differences among three groups(P<0.05). When compared in pairs, there were significant differences between Grade I and Grade III(P<0.01) as well as Grade II and Grade III(P<0.05). But the difference between Grade I and Grade II showed no significance. The positive rate of LRIG1 expression in patients with axillary lymphatic metastasis was significantly lower than that in patients without axillary lymphatic metastasis(P<0.05). The expression of LRIG1 in ER negative group was significantly lower than ER positive group(P<0.05), while the expression of LRIG1 in HER2 negative group was significantly higher than HER2 positive group(P<0.01),illustrate the ER、HER2 was related with the expression of LRIG1.There was no significant correlation between the expression of LRIG1 and PR(P>0.05).The expression of LRIG1 was different in various tumor molecular classifications(P<0.05). When compared in pairs, there were significant differences between Luminal A and TNBC(P<0.05) as well as Luminal B and TNBC(P<0.05). No significant difference among other groups was observed.2. The positive rate of EGFR expression in invasive breast cancer tissues was 56.8%, which was significantly higher than that in normal pericarcinous breast tissues(12.5%, P<0.01). There was no significant correlation between the expression of EGFR and age, tumor size(P>0.05). The expression of EGFR was related to clinical TNM stage,and there was significant difference among four groups(P<0.05).Statistical analysis showed that the histological grade was related with the expression of EGFR and there were significant differences among three groups(P<0.05).When compared in pairs, there were significant differences between Grade I and Grade III(P<0.01),while the differences between Grade I and Grade II as well as Grade II and Grade III showed no significance.The positive rate of EGFR expression in patients with axillary lymphatic metastasis was significantly higher than that in patients without axillary lymphatic metastasis(P<0.01). The expression of EGFR in ER negative group was significantly higher than ER positive group(P<0.05), while the expression of EGFR in HER2 positive group was significantly higher than HER2 negative group(P<0.05).There was no significant correlation between the expression of EGFR and PR(P>0.05).The positive expression of EGFR was different in various tumor molecular classifications(P<0.05). When compared in pairs,there were significant differences between Luminal A and Luminal B(P<0.05),there were significant differences between Luminal A and HER2 overexpression group(P<0.01) as well as Luminal A and TNBC(P<0.05). No significant difference among other groups was observed.3. The expressions of LRIG1 and EGFR in invasive breast cancer showed negative correlation(P<0.01, r=-0.674).4. Kaplan-Meier univariate survival analysis showed that,in invasive breast cancer patients,the five-year overall survival in LRIG1 protein positive group more than the negative group(94.4%,73.1%),the difference was statistically significant(χ2 =6.27,P<0.05).In patients with invasive breast cancer,five-year overall survival rate of EGFR positive group less than the negative group(74.0 %, 92.1 %),the difference was statistically significant( χ2 =4.58,P<0.05). Conclusions:1. The positive rate of LRIG1 expression in invasive breast cancer tissues was significantly lower than that in normal pericarcinous breast tissues, The positive rate of EGFR expression in invasive breast cancer tissues was significantly higher than that in normal pericarcinous breast tissues.2.The expressions of LRIG1 and EGFR in invasive breast cancer show negative correlation.3.The low expression of LRIG1 and the high expression of EGFR are correlation with poor prognosis in invasive breast cancer.