Expression And Clinicopathological Significance Of APOBEC3B In Invasive Ductal Carcinoma

Objective:To investigate the expression of APOBEC3 B gene in invasive ductal carcinoma, analyze the relationship between APOBEC3 B and the occurrence and development of invasive ductal carcinoma and its clinical significance. Methods:(1) The expression of APOBEC3 B m RNA was determined by RT-q PCR in 32 cases of invasive ductal carcinoma samples and carcinoma adjacent breast tissue samples and in 10 cases of normal breast tissue samples.(2)The expression of APOBEC3 B protein was determined in 32 cases which used in PT-q PCR by immunohistochemistry. The correlation of APOBEC3 B protein and APOBEC3 B m RNA was analyzed. In addition, the expression of APOBEC3 B protein was determined in 80 cases of invasive ductal carcinoma samples and carcinoma adjacent breast tissue samples by immunohistochemistry. The correlation of APOBEC3 B protein to clinicopathologic significance of invasive ductal carcinoma was analyzed. Results:(1) APOBEC3 B m RNA expressed in invasive ductal carcinoma tissues, carcinoma adjacent breast tissues and normal breast tissues. The expression of APOBEC3 B m RNA was significantly higher in invasive ductal carcinoma tissues than carcinoma adjacent breast tissues and normal breast tissues(P<0.05).(2)The expression of APOBEC3 B protein was correlated with the expression of APOBEC3 B m RNA. If the expression of APOBEC3 B m RNA was high, the expression of APOBEC3 B protein was also high.(3)There was different degree expression of APOBEC3 B protein in breast invasive ductal carcinoma tissues. The positive rate of APOBEC3 B protein expression in breast invasive ductal carcinoma tissues was 44.64%(50/112).APOBEC3 B protein was little expressed in carcinoma adjacent breast tissues. The positive rate of APOBEC3 B protein expression in carcinoma adjacent breast tissues was 25.89%(29/112). The expression of APOBEC3 B protein was significantly higher in invasive ductal carcinoma tissues than carcinoma adjacent breast tissues(P<0.05).(4)The expression of APOBEC3 B protein in breast invasive ductal carcinoma was correlated with histological grade, lymph node metastasis, the molecular typing and the expression of ER, PR, HER-2, not correlated with patients ’age, tumor size and the expression of p53、CK5/6 and nm23. The expression of APOBEC3 B protein was higher in histological grade Ⅲof invasive ductal carcinoma tissues than that in histological gradeⅠand grade Ⅱ of invasive ductal carcinoma tissues, a statistically significant difference(P<0.05). There was no difference in histological grade Ⅰand grade Ⅱ of invasive ductal carcinoma tissues. The expression of APOBEC3 B protein was higher in lymph node metastasis positive patients than that in negative patients, a statistically significant difference(P<0.05). The expression of APOBEC3 B protein was higher in luminal A than that in luminal B and Her2-overexpression, a statistically significant difference(P<0.05). There was no difference in other groups. The expression of APOBEC3 B protein was higher in ER-positive group than that in ER-negative group, a statistically significant difference(P<0.05).The expression of APOBEC3 B protein was higher in PR-positive group than that in PR-negative group, a statistically significant difference(P<0.05).The expression of APOBEC3 B protein was lower in HER2-negative group than that in HER2-positive group, a statistically significant difference(P<0.05). Conclusion:(1)The expression of APOBEC3 B m RNA and protein was much higher in some breast invasive ductal carcinoma tissues, which indicates that APOBEC3 B may play an important role in the genesis and development of breast invasive ductal carcinoma.(2)The expression of APOBEC3 B protein in breast invasive ductal carcinoma was correlated with histological grade and lymph node metastasis, which indicates that APOBEC3 B may be an element which affects the migration and invasion of breast invasive ductal carcinoma.(3)The expression of APOBEC3 B protein in breast invasive ductal carcinoma was correlated with the molecular typing and the expression of ER, PR, HER-2, which indicates that APOBEC3 B may be a new target in evaluating the therapy of breast invasive ductal carcinoma.