Promotes Liver Cancer Cell Proliferation Research Articles

CD5L is upregulated in hepatocellular carcinoma and promotes liver cancer cell proliferation and antiapoptotic responses by binding to HSPA5 (GRP78).

CD5-like (CD5L) is a soluble scavenger cysteine-rich protein that modulates inflammatory responses. We studied the involvement of CD5L in liver cancer. Immunohistochemistry (IHC) of CD5L in 60 hepatocellular carcinomas and 34 adjacent nontumor livers, showed that CD5L staining was higher in tumor than in nontumor tissue (Mann-Whitney test; P = 0.0039). High CD5L correlated with elevated proliferation (Ki67, linear regression; P < 0.0001) and lower patient event-free survival (log-rank; P = 0.0185). Accordingly, CD5L expression was detected in the liver cancer cell lines Huh7, HepG2, and SNU-398. In vitro technologies using these cell lines, including small interfering RNA (siRNA) and cDNA transfection, showed that CD5L promoted colony formation and cell proliferation and protected against cisplatin-induced apoptosis. To find a molecular explanation for these roles, novel CD5L-interacting protein ligands in liver cancer cells were identified by immunoprecipitation followed by mass spectrometry. Among these, the molecular chaperone of the unfolded protein response (UPR), heat shock protein (HSP)-A5, was selected for validation. The interaction was confirmed by confocal microscopy in the Huh7 and HepG2 cell lines. Furthermore, functional experiments revealed that CD5L activates the UPR and autophagy mechanisms in Huh7 cells, thereby providing a novel molecular link between the UPR and autophagy in liver cancer.-Aran, G., Sanjurjo, L., Bárcena, C., Simon-Coma, M., Téllez, É., Vázquez-Vitali, M., Garrido, M., Guerra, L., Díaz, E., Ojanguren, I., Elortza, F., Planas, R., Sala, M., Armengol, C., Sarrias, M.-R. CD5L is upregulated in hepatocellular carcinoma and promotes liver cancer cell proliferation and antiapoptotic responses by binding to HSPA5 (GRP78).

High GSTP1 inhibits cell proliferation by reducing Akt phosphorylation and is associated with a better prognosis in hepatocellular carcinoma.

Glutathione S-transferase (GST) family members promote carcinogenesis and cancer progression. We assessed GST pi 1 (GSTP1) mRNA and protein levels in hepatocellular carcinoma (HCC) using genome databases and tissue microarray (TMA) technology. We found that in cancerous tissues, GSTP1 mRNA was down-regulated in genome databases, and immunohistochemical staining of GSTP1 in 237 HCC cases varied from negative to strongly positive. GSTP1 levels correlated negatively with tumor size and serum alpha-fetoprotein (AFP) in HCC patients, and higher GSTP1 levels associated with longer overall survival (OS) and disease-free survival (DFS). We also found that GSTP1 overexpression restrained HepG2 and Huh7 liver cancer cell proliferation in vivo and in vitro. GSTP1 arrested the cell cycle at G1/S by up-regulating p21 and p27 and down-regulating p-Akt. Interrupting GSTP1 gene expression promoted liver cancer cell proliferation and increased the percentage of cells in S phase by decreasing levels of p21 and p27 and increasing p-Akt. These results suggest high GSTP1 levels provide a better prognosis through suppression of tumorigenesis in HCC.

MiR-935 Promotes Liver Cancer Cell Proliferation and Migration by Targeting SOX7.

Hepatocellular carcinoma (HCC) is the most common cancer in the world. MicroRNAs (miRNAs) are a type of small noncoding RNA that can regulate the expression of target genes under physiological and pathophysiological conditions. Aberrant expression of microRNA-935 (miR-935) has been reported in cancer studies. However, its expression and mechanism in HCC remain unclear. In our study, we found that miR-935 was upregulated in liver cancer tissues and cells. Overexpression of miR-935 in liver cells promoted cell proliferation, tumorigenesis, and cell cycle progression, whereas inhibition of miR-935 reduced cell proliferation, tumorigenicity, and cell cycle progression. These changes in the properties of HCC cells were associated with upregulation of two well-known cellular G1/S transitional regulators: cyclin D1 and c-Myc. Additionally, we identified SOX7 as a direct target of miR-935. Overexpression of miR-935 inhibited SOX7 expression but promoted the levels of c-Myc and cyclin D1, which promotes cell proliferation and tumorigenesis; knockdown of miR-935 increased SOX7 level and inhibited c-Myc and cyclin D1 expression, whereas SOX7 silencing could promote cell proliferation, cell motility, and invasiveness in vitro. Our findings suggest that miR-935 represents a biomarker and a potential new target in HCC progression by suppressing SOX7 expression.

Acetylation of PGK1 promotes liver cancer cell proliferation and tumorigenesis.

These findings demonstrate a novel regulation of PGK1 as well as its important role in liver cancer progression. (Hepatology 2017;65:515-528).

Abstract 5032: Acute phase liver graft injury mobilizes regulating B cells after transplantation for HCC patients through TLR4/CXCL10/CXCR3 signaling

Abstract We aim to investigate the impact of acute-phase small-for-size graft injury on mobilization of circulating regulating B cells (Bregs) in HCC patients after liver transplantation and to explore the molecular mechanism therein. Methods From May 2000 to November 2009, 115 HCC recipients were included. The intragraft gene expression profile and Bregs infiltration of the grafts greater (Group 1) and less than 60% (Group 2) of standard liver weight (SLW) were detected by RT-PCR and immunostaining. Circulating Bregs (CD19+CD24hiCD38hi) were compared by FACS analysis after transplantation. Clinical-pathological data including the incidence of tumor recurrence and metastasis were compared. The direct roles of TLR4, CXCL10 and CXCR3 on circulating Bregs mobilization were investigated in TLR4-/-, CXCL10-/- and CXCR3-/- mice models, respectively. The association of intragraft Bregs infiltration and tumor invasiveness were also examined in a rat liver transplantation for liver cancer model. The role of Bregs on liver tumor growth and invasiveness were further studied in a series of in vitro and in vivo functional experiments. Results The patients were grouped into Group 1 (&amp;gt; = 60% SLW, n = 37) and Group 2 (&amp;lt;60% SLW, n = 78). Much more patients in Group 2 developed tumor recurrence and lung metastasis [19/78(24.4%) vs 3/37(8%), p = 0.04]. Level of circulating Bregs was significantly higher in Group 2 (Week1: 7.02 vs 1.31/10^5PBMC, p = 0.03; month3: 5.7 vs 1.3/10^5PBMC, p = 0.03). There was more intragraft Bregs infiltration in group 2 indicated by CD20/IL10 staining. Intragraft gene expression of TLR4, CXCL10 and CXCR3 were significantly higher in Group 2 at early phase after transplantation. In rat liver transplantation model, more Bregs infiltration at early phase after transplantation correlated with late phase invasive tumor growth. Levels of circulating Bregs were significantly lower in the mice model with major hepatectomy and hepatic I/R injury using TLR4-/-, CXCL10-/- and CXCR3-/- mice, respectively. Bregs also promoted liver cancer cell proliferation and migration in vitro, and tumor growth in vivo. Conclusion A significantly higher population of circulating Bregs, which are mobilized by small-for-size graft injury, may lead to a higher incidence of tumor recurrence and metastasis after LDLT. TLR4/CXCL10/CXCR3 signaling may play important roles on Bregs mobilization. Citation Format: Kwan Man, Yan Shao, Chang Xian Li, Chung Mau Lo. Acute phase liver graft injury mobilizes regulating B cells after transplantation for HCC patients through TLR4/CXCL10/CXCR3 signaling. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5032. doi:10.1158/1538-7445.AM2015-5032

Adipose tissue-secreted miR-27a promotes liver cancer by targeting FOXO1 in obese individuals.

The current notion that obesity is a major risk factor for the development of and the mortality associated with a subset of liver cancer is well appreciated. However, detailed mechanistic insights underlying this relationship are lacking. Better understanding of the adipose tissue-secreted miRNAs that play a potential role in defining primary liver cancer development and mediating the obesity-cancer communication offers the potential for new insights into tumor growth and interventions to modulate tumor formation and progression. In this study, we clearly demonstrated that miR-27a is more highly upregulated in cancer, plasma, and adipose samples from obese liver cancer cases, and therefore reasoned that miR-27a excreted from adipose tissue leads to liver cancer development. To address this idea, we prepared miR-27a-overexpressing 3T3-L1 adipocytes and cocultured them with HepG2 liver cancer cells. Our results demonstrated that secretory miR-27a promoted liver cancer cell proliferation through the downregulation of the transcription factor FOXO1 and promoted the G1/S cell cycle transition by decreasing the cell cycle inhibitors p21 and p27 and increasing the cell cycle regulator cyclin D1. These findings improve our understanding of the involvement of miR-27a in obesity-liver cancer communication and might provide a novel putative target for obesity-driven primary liver cancer diagnosis and therapy.

Pyruvate kinase M2 affects liver cancer cell behavior through up-regulation of HIF-1α and Bcl-xL in culture

Cancer cells consume large amounts of glucose to produce lactate, even in the presence of ample oxygen. This phenomenon is known as the Warburg effect. The pyruvate kinase promotes aerobic glycolysis, and the pyruvate kinase M2 isoform (PKM2) is highly expressed in many cancer cells. Although the Warburg effect is a hallmark of cancer, the mechanism by which PKM2 contributes to the Warburg effect, and its role in tumor growth remain to be defined. We proposed that PKM2 activates transcription of hypoxia inducible factor-1α (HIF-1α) by phosphorylating STAT3 (signal transducer and activator of transcription 3) at Y705 (tyrosine 705) as a plausible mechanism for liver cancer cell proliferation. In the current study, we observed that PKM2 was over-expressed in hepatocellular carcinoma (HCC) tissues compared to adjacent normal tissues. The experiments further indicate that nuclear PKM2 is an active protein kinase in cultured cells. Knockdown of PKM2 affected the levels of HIF-1α and Bcl-xL (B-cell lymphoma-extra large), suggesting that PKM2 plays an important role in promoting cell proliferation. In conclusion, the current findings demonstrate that PKM2 is an active protein kinase, and promotes liver cancer cell proliferation by up-regulating HIF-1α and Bcl-xL expression.

Increased expression of glycinamide ribonucleotide transformylase is associated with a poor prognosis in hepatocellular carcinoma, and it promotes liver cancer cell proliferation.

Glycinamide ribonucleotide transformylase (GART) is a folate-dependent enzyme in the de novo purine pathway that has been the target of antineoplastic intervention for almost 2 decades. Until now, its expression and functional significance in hepatocellular carcinoma (HCC) have been unclear. We demonstrated by Western blotting that the expression of GART was markedly up-regulated in HCC patients. Immunohistochemistry staining was used to determine the expression of GART in HCC and adjacent nontumor tissues from 96 patients. Increased expression of GART correlated positively with the histologic grade (P = .001), tumor size (P = .043), number of tumorous nodes (P = .020), and intrahepatic metastases (P = .031), suggesting a role for GART in the progression of HCC. Patients with higher GART expression had a much worse overall survival rate than those with low expression (P = .002). Furthermore, multivariate analysis showed that GART expression was an independent predictor of overall survival (hazard ratio, 2.265; 95% confidence interval, 1.335-3.842; P = .002). Depletion of GART by small interfering RNA inhibited cell proliferation and blocked S-phase and mitotic entry in cultured HepG2 and BEL-7404 cells. Western blot analyses showed that GART depletion decreased the proliferating cell nuclear antigen concentration. Collectively, our clinical and in vitro data indicate that GART expression may be one of the causative factors for a poor prognosis in HCC.