3313

HSPA9

heat shock 70kDa protein 9 (mortalin);HSPA9;heat shock 70kDa protein 9 (mortalin)

75 kDa glucose-regulated protein|catecholamine-regulated protein 40|epididymis secretory sperm binding protein Li 124m|heat shock 70kD protein 9B|mortalin, perinuclear|mortalin-2|p66-mortalin|peptide-binding protein 74|stress-70 protein, mitochondrial

5q31.1

protein-coding

Hepatocellular carcinoma (HCC) is well known for poor prognosis and short survival because of high recurrence rate even after curative surgery. Today there is no available biomarker or biochemical test to indicate HCC recurrence, and this study aims to identify protein markers that can discriminate postoperative patients with early recurrence (ER), i.e. disease relapsed within the first year. In this study, 103 hepatitis B-related HCC patients were recruited, and 68 of them were used for ER-related biomarker discovery study. Proteomic expression patterns of matched tumor and adjacent non-tumor tissues from these patients plus 16 normal liver tissues were delineated by the two-dimensional gel electrophoresis differential profiling method. Significant protein spots were evaluated by hierarchical clustering analysis. SSP4612 that yielded the highest receiver operating characteristic (ROC) curve value for the ER subgroup of HCC was subsequently identified by tandem mass spectrometry, and the corresponding expression patterns were further confirmed by quantitative PCR, Western blot, and immunohistochemistry. Correlation analysis with clinicopathological data was also examined. Proteomic profiling analysis revealed overexpression of mortalin (gene HSPA9) in HCC when compared with the non-tumor and normal liver tissues (area under the curve (AUC) = 0.821). Furthermore, elevated mortalin level was also detected in the ER subgroup of HCC versus the recurrence-free state (where no cancer recurs for >1 year) (AUC = 0.833, sensitivity = 90.9%, specificity = 71.4%). metastatic HCC cell lines also exhibited higher levels of mortalin and HSPA9 mRNA. Clinically, mortalin overexpression in HCC was closely associated with advanced tumor stages and venous infiltration, having implications for increased malignancy and aggressive behavior. Mortalin (HSPA9) is associated with HCC metastasis and thus suggested as a tumor marker for predicting early recurrence, which may have immediate clinical applications for cancer surveillance after curative surgery.

Mortalin is highly expressed in a variety of human tumors and associated with tumor metastasis. However, the relationship among the overexpression of Mortalin, epithelial to mesenchymal transition (EMT) and neovascularization is largely unknown. The aim of the present study was to investigate the expression of Mortalin in human HCC cell lines, clinical HCC specimens and its association with angiogenesis and EMT. The results of our study showed that the expression levels of Mortalin in cell lines with higher metastatic potential were significantly higher compared to those with lower metastatic potential. Compared with paracarcinomatous tissues and normal liver tissues, the expression of Mortalin was significantly increased in HCC tumor tissues. The expression of Mortalin was correlated with invasion and metastasis, Edmondson grade and TNM stage. A significant positive correlation was found between the expression of Mortalin and Vimentin, and tumors with high expression of Mortalin had a tendency to higher MVD compared to those with low expression of Mortalin. Using shRNA-mediated Mortalin knockdown, we found that decreased expression of Mortalin was accompanied by a reduction of Vimentin expression. Our findings demonstrated that the overexpression of Mortalin is correlated with the metastatic phenotype of HCC cells and can promote EMT, but cannot induce angiogenesis in HCC. The decreased expression of Mortalin is accompanied by an inhibition of EMT in the HCC cell lines.