High Expression of PKCζ and ALDH1A3 Is Associated With Poor Prognosis in Luminal B Breast Cancer

The relationship between the protein kinase C zeta (PKCζ) and aldehyde dehydrogenase 1 family member A3 (ALDH1A3) expression levels and endocrine therapy susceptibility in luminal A and luminal B breast cancer subtypes is unclear. Therefore, the present study aimed to analyze this relationship in terms of disease-specific survival.

Open-source datasets with clinical and gene expression information (METABRIC, n=2509; and TCGA Pan-Cancer Atlas, n=1084) were downloaded and analyzed. Kaplan-Meier survival and Cox proportional hazard analyses were performed.

The results indicated that high PKCζ and ALDH1A3 expression levels were associated with a poor prognosis in patients with luminal B type breast cancer treated with endocrine therapy, including aromatase inhibitors. These results suggest that high expression of PKCζ and ALDH1A3 contributes to reduced effectiveness of endocrine therapy in patients with luminal B breast cancer.

PKCζ may be involved in the progression of ALDH1A3-positive luminal B breast cancer. Furthermore, PKCζ and ALDH1A3 could serve as molecular targets and prognostic biomarkers for predicting the efficacy of endocrine therapy in patients with ALDH1A3 positive luminal B breast cancer.