High expression of carbonic anhydrase 12 (CA12) is associated with good prognosis in breast cancer.

The purpose of this research was to explore whether the expression of carbonic anhydrase 12 (CA12) and the prognosis had a significant relationship in breast cancer patients. A total of 262 breast cancer specimens and 75 normal breast tissue specimens were recruited in this study. The expression of CA12 was detected by immunohistochemistry (IHC), and its correlation with the clinicopathological characteristics of breast cancer patients and their prognosis were further analyzed through standard statistical algorithms. The result of immunohistochemical staining showed that CA12 was detected in both normal breast tissue and breast cancer tissue. Compared to normal breast tissue, CA12 was significant higher expressing in cancer tissues (P=0.009). Statistical analysis showed that the high expression of CA12 in breast cancer tissue was related to estrogen receptor expression level (P<0.001). The follow-up of 262 cases of breast cancer patients within 5 years showed that patients with high expression of CA12 had significant better outcome in DFS (P=0.020) and OS (P=0.019) than patients with low expression of CA12. Univariate analysis of DFS showed that lymph node metastasis (P=0.034) and CA12 (P=0.024) are prognostic indicators. Multivariate analysis manifested that the expression of CA12 (P=0.025) and lymph node metastasis (P=0.024) are two independent factors affecting the prognosis of breast cancer. Conclusion: In breast cancer patients, CA12 can be seen as a new prognostic indicator and even a new target for treatment.