Low expression of spindle checkpoint protein, Cenp-E, causes numerical chromosomal abnormalities in HepG-2 human hepatoma cells

CENPL accelerates cell proliferation, cell cycle, apoptosis, and glycolysis via the MEK1/2-ERK1/2 pathway in hepatocellular carcinoma

Centromere protein L (CENPL) is involved in the mitotic process of eukaryotic cells and the development of various types of cancer. However, its role in hepatocellular carcinoma (HCC) remains unclear. This study aimed to investigate the expression and clinical significance of CENPL in HCC, and explore its involvement in regulating HCC cell proliferation, apoptosis, cell cycle, and glycolysis both in vivo and in vitro. CENPL expression was analyzed in HCC and normal liver tissues using The Cancer Genome Atlas, Gene Expression Omnibus mining, real-time quantitative polymerase chain reaction, and immunohistochemistry. Functional assays were used to assess the role of CENPL in HCC cell proliferation, apoptosis, cell cycle, and glycolysis. The potential pathways underlying the regulatory effects of CENPL, as well as the expression of mitogen-activated protein kinase (MAPK) signaling pathway-related molecules and markers of proliferation and glycolysis were investigated. CENPL was significantly upregulated in HCC tissue and associated with multiple clinicopathological features and poor patient prognosis. Univariate and multivariate analyses demonstrated that CENPL may serve as an independent prognostic factor for HCC. Upregulation of CENPL in HCC regulated tumor proliferation and glycolytic processes. Mechanistic studies revealed that differentially expressed genes between the CENPL-overexpressing and control groups were mainly concentrated in the MAPK signaling pathway. Pathway inhibition analysis indicated that CENPL activated the MEK1/2-ERK1/2 signaling pathway to promote proliferation and glycolysis in HCC cells. This study elucidated the role of CENPL in regulating cell proliferation, apoptosis, cell cycle, and glycolysis in HCC. CENPL may represent a therapeutic target and prognostic biomarker for HCC.

High mRNA Expression of CENPL and Its Significance in Prognosis of Hepatocellular Carcinoma Patients

Centromere proteins (CENPs) are the main constituent proteins of kinetochore, which are essential for cell division. In recent years, several studies have revealed that several CENPs were aberrantly expressed in hepatocellular carcinoma (HCC). However, numerous centromere proteins have not been studied in HCC. In this study, we used databases of Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA), the Kaplan-Meier Plotter, cBioPortal, the Human Protein Atlas (HPA), and TIMER (Tumor Immune Estimation Resource) and immunohistochemical staining of clinical specimens to investigate the expression of 15 major centromere proteins in HCC to evaluate their potential prognostic value. We found that the mRNA levels of 4 out of 15 centromere proteins (CENPL, CENPQ, CENPR, and CENPU) were significantly higher in HCC than in normal tissues, and their mRNA levels were associated with the tumor stages (p values < 0.01). Patients with higher mRNA levels of CENPL had poorer overall survival, progression-free survival, relapse-free survival, and disease-specific survival (p values < 0.05). Furthermore, the higher levels of CENPL mRNA were associated with worse overall survival in males without hepatitis virus infection (p values < 0.05). The protein expression level of CENPL in human HCC tissue was higher than that in normal liver tissue. In addition, the expression of CENPL was positively correlated with the levels of the tumor-infiltrating lymphocytes. The results suggest that the high mRNA expression of CENPL may be a potential predictor of prognosis in HCC patients.

Reduced expression of CENP-E contributes to the development of hepatocellular carcinoma and is associated with adverse clinical features

Human kinesin centromere-associated protein E (CENP-E), one of spindle checkpoint proteins, has been identified as a tumor suppressor in several types of cancer, however, its role in hepatocarcinogenesis remains unknown. Here we investigated the role of CENP-E in human hepatocellular carcinoma (HCC) employing HCC cell lines (Hep3B, SMMC7721, and QGY7701), animal models, and patient's clinical samples and data. We demonstrated that down-regulation of CENP-E by CENP-E-silencing shRNAs significantly promoted HCC proliferation/growth both in vitro and in vivo. Further studies found that CENP-E suppressed the proliferation of HCC cells by halting cell cycle progression at the G1-S phase and accelerating cell apoptosis. Analyses of HCC patient samples and clinical data revealed that CENP-E was significantly down-regulated in HCC tissues and low CENP-E expression was significantly associated with patient's adverse clinicopathological features: poor prognosis, advanced TNM stage, metastasis, and larger tumor size. Multivariate analysis indicated that CENP-E was an independent prognostic factor predicting outcomes of advanced HCC patients. Our data suggest that loss of CENP-E contributes to HCC development and is strongly associated with adverse HCC clinical pathology. Thus, CENP-E could be a novel target for new treatments and a useful prognostic biomarker for HCC patients.