Intracellular localization of CK2α as a prognostic factor in invasive breast carcinomas. Issue 2 (13th January 2021)

• Record Type: Journal Article
• Authors: Homma, Miwako Kato; Kiko, Yuichiro; Hashimoto, Yuko; Nagatsuka, Miki; Katagata, Naoto; Masui, Seiichiro; Homma, Yoshimi; Nomizu, Tadashi
• Is Part Of: Cancer science. Volume 112:Issue 2(2021)
• Page Start: 619
• Page End: 628
• Publication Date: 2021-01-13
• Subjects: breast cancer -- invasive ductal carcinoma -- nucleus -- prognostic factor -- protein kinase CK2; Cancer -- Periodicals; Neoplasms -- Periodicals; Research -- Periodicals; Electronic journals; 616.994005
• DOI: 10.1111/cas.14728
• Languages: English
• ISSNs: 1347-9032

Abstract

Abstract: Overexpression of the ubiquitous protein kinase, CK2α, has been reported in various human cancers. Here, we demonstrate that nuclear and nucleolar CK2α localization in invasive ductal carcinomas of the breast is a reliable predictor of poor prognosis. Cellular localization of CK2α in nuclei and nucleoli was analyzed immunohistochemically using surgical tissue blocks from 112 patients, who had undergone surgery without neoadjuvant chemotherapy. Clinical data collection and median follow‐up period were for more than 5 y. In total, 93.8% of patients demonstrated elevated CK2α expression in nuclei and 36.6% of them displayed elevated expression predominantly in nucleoli. Clinicopathological malignancy was strongly correlated with elevated nuclear and nucleolar CK2α expression. Recurrence‐free survival was significantly worse ( P = .0002) in patients with positive nucleolar CK2α staining. The 5‐y survival rate decreased to a roughly 50% in nucleolar CK2α‐positive patients of triple‐negative ( P = .0069) and p Stage 3 ( P = .0073) groups. In contrast, no patients relapsed or died in the triple‐negative group who exhibited a lack of nucleolar CK2α staining. Evaluation of nucleolar CK2α staining showed a high secondary index with a hazard ratio of 6.629 ( P = .001), following lymph node metastasis with a hazard ratio of 14.30 ( P = .0008). Multivariate analysis demonstrated that nucleolar CK2α is an independent factor for recurrence‐free survival. Therefore, we propose that histochemical evaluation of nucleolar CK2α‐positive staining may be a new and robust prognostic indicator for patients who need further treatment. Functional consequences of nucleolar CK2 dysfunction may be a starting point to facilitate development of novel treatments for invasive breast carcinoma. Abstract : Nucleolar CK2 localization is a useful marker for predicting adverse outcomes of patients with invasive ductal breast carcinomas who underwent surgical resection of the tumor. Evaluation of nucleolar CK2 can be considered as an independent prognostic factor. This new and robust prognostic indicator may enhance the efficacy for patients who need further treatment.