Phosphorylated protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) expression in breast cancer is correlated with malignant proliferation and histological grading.

This study aims to detect the expression of phosphorylated PERK in breast cancer using immunohistochemistry and explore its significance. We examined 134 cases of formalin-fixed and paraffin-embedded breast cancer tissues. It was found that the expression of phosphorylated PERK in ductal carcinoma was higher than that in lobular carcinoma, and the difference between them was statistically significant, suggesting that phosphorylated PERK played different roles in the occurrence and development of different types of breast cancer. Compared with Ki-67-negative breast cancer tissues, phosphorylated PERK has higher expression in Ki-67-positive tissues and is positively correlated with Ki67 expression, indicating that phosphorylated PERK plays an important role in breast cancer's malignant proliferation and progression. We also found a positive correlation between phosphorylated PERK expression and the histological grading of invasive ductal carcinoma, indicating that phosphorylated PERK plays an important role in the differentiation of invasive ductal carcinoma. Our study revealed the differential expression of phosphorylated PERK in subtypes of breast cancer. It contributed to the malignant proliferation of breast cancer and tissue differentiation of invasive ductal carcinoma of the breast.