Expression And Significance Of PLOD2 In Breast Cancer

Objective: Breast cancer is one of the most common malignant tumors in women and its morbidity and mortality are high in contemporary society.The five-year survival rate of breast cancer patients is not low,but the poor prognosis of breast cancer increases the risk of death.Understanding the mechanism of occurrence and development of breast cancer is of great significance for the recurrence,treatment and prognosis of patients with breast cancer.Procollagen-lysine-2-oxyglutarate-5-dioxygenase2(PLOD2)is one of the markers that have been found to have an impact on breast cancer in recent years,which is related to the synthesis of collagen fibrosis.PLOD2 protein is one of the homodimer of lysyl hydroxylase(LH).By hydroxylating lysine in the peptide region of collagen,it affects two ways of collagen synthesis to promote the formation of pyridine crosslink,which is difficult to degrade and easy to gather to form fibers.Collagen provides abundant protein for the extracellular matrix(ECM),but fibrotic collagen is considered as a “highway” for cancer cell migration and invasion.Current experimental studies at home and abroad have proven that PLOD2 gene is highly expressed in many solid tumors,such as breast cancer,cervical cancer,and lung cancer.The discovery and in-depth study of PLOD2 help to strengthen the indepth treatment of breast cancer.The purpose of this study is to detect the expression level of PLOD2 in breast cancer and to evaluate the relationship between PLOD2 and clinic pathological characteristics and prognosis of breast cancer.Methods: The expression of 50 paired samples' PLOD2 in breast cancer tissues,paracancerous tissues,and normal tissues were examined by immunohistochemistry under different conditions of size,stage,estrogen receptor(ER)status,progesterone receptor(PR)status,human epidermal growth factor receptor-2(HER-2)status,Ki-67 status and lymph node metastasis of breast cancer.Results: PLOD2 was expressed in the cytoplasm of breast cancer and its expression in breast cancer is significantly higher than that in paracancerous tissues and normal tissues(P>0.001).In breast cancer,high expression of PLOD2 was associated with lymph node metastasis(P=0.001).PLOD2 expression increased with the increasement of tumor stage(P=0.003)and PR expression(P=0.001),however,its expression increased with the decreasement of Ki-67 expression(P<0.001).There was no significant correlation between age,tumor size,ER status,HER-2 status and positive expression of PLOD2,and the difference was not statistically significant(P>0.05).Conclusion: PLOD2 expression was positively correlated with tumor stage and lymph node metastasis in breast cancer tissues.Through combined with its occurrence and development mechanism,PLOD2 was considered involved in the process of the distant metastasis of breast cancer,leading to poor prognosis.The expression of PLOD2 was positively correlated with the expression of PR,and negatively correlated with the expression of Ki-67,suggesting that PLOD2 may be related to the proliferation of breast cancer cells,while the high expression of PLOD2 inhibits the proliferation of tumor cells.The specific mechanism is still unclear.These results suggest a novel molecular mechanism of breast cancer tumorigenesis,providing a potential therapeutic target for breast cancer.It has certain reference value and guiding significance for the prediction of breast cancer prognosis.