High mRNA Expression Levels of Heat Shock Protein Family B Member 2 (<i>HSPB2</i>) Are Associated with Breast Cancer Patients’ Relapse and Poor Survival

Small heat shock proteins (sHSPs) are ubiquitous ATP-independent chaperones that contribute to the maintenance of proteome integrity and functionality. Recent evidence suggests that sHSPs are ubiquitously expressed in numerous types of tumors and have been proposed to be implicated in oncogenesis an...

Full description

Bibliographic Details
Main Authors: Aimilia D. Sklirou, Despoina D. Gianniou, Paraskevi Karousi, Christina Cheimonidi, Georgia Papachristopoulou, Christos K. Kontos, Andreas Scorilas, Ioannis P. Trougakos
Format: Article
Language:English
Published: MDPI AG 2022-08-01
Series:International Journal of Molecular Sciences
Subjects:
Online Access:https://www.mdpi.com/1422-0067/23/17/9758
Description
Summary:Small heat shock proteins (sHSPs) are ubiquitous ATP-independent chaperones that contribute to the maintenance of proteome integrity and functionality. Recent evidence suggests that sHSPs are ubiquitously expressed in numerous types of tumors and have been proposed to be implicated in oncogenesis and malignant progression. Heat shock protein family B member 2 (HSPB2) is a member of the sHSPs, which is found to be expressed, among others, in human breast cancer cell lines and constitutes an inhibitor of apical caspase activation in the extrinsic apoptotic pathway. In this study, we investigated the potential prognostic significance of <i>HSPB2</i> mRNA expression levels in breast cancer, which represents the most frequent malignancy in females and one of the three most common cancer types worldwide. To this end, malignant breast tumors along with paired non-cancerous breast tissue specimens were used. <i>HSPB2</i> expression levels were quantified in these two cohorts using a sensitive and accurate SYBR green-based quantitative real-time polymerase chain reaction (q-RT-PCR). Extensive biostatistical analyses were performed including Kaplan–Meier and Cox regression survival analyses for the assessment of the results. The significant downregulation of <i>HSPB2</i> gene expression was revealed in breast tumors compared to their adjacent non-cancerous breast tissues. Notably, high <i>HSPB2</i> mRNA expression predicts poor disease-free survival and overall survival of breast cancer patients. Multivariate Cox regression analysis revealed that <i>HSPB2</i> mRNA overexpression is a significant predictor of poor prognosis in breast cancer, independent of other clinicopathological factors. In conclusion, high <i>HSPB2</i> mRNA expression levels are associated with breast cancer patients’ relapse and poor survival.
ISSN:1661-6596
1422-0067