Yongqiang Li

SKF95365 induces apoptosis and cell-cycle arrest by disturbing oncogenic Ca 2+ signaling in nasopharyngeal carcinoma cells

Background Aberrant modulation of store-operated calcium ions (Ca2+) entry promotes the progression of human malignancies. Previously, we reported that the blockage of store-operated Ca2+ entry inhibited epidermal growth factor (EGF)-stimulated migration and distant metastasis in nasopharyngeal carcinoma (NPC) cells. However, the effects of pharmacological blocker on other Ca2+ signaling-regulated malignant characteristics in NPC cells remained poorly understood. Methods We examined the effects of SKF96365, an inhibitor of store-operated Ca2+ channel, on EGF-launched Ca2+ signaling in two NPC cell lines. We determined the effects of SKF96365 on cell proliferation, colony formation, apoptosis, and cell-cycle status in vitro. We further elucidated the antitumor activity of SKF96365 in xenograft-bearing mice. Results It was found that SKF96365 disturbed the thapsigargin (TG)-stimulated Ca2+ release from endoplasmic reticulum and the subsequent Ca2+ influx. SKF96365 alone stimulated Ca2+ responses merely due to endoplasmic reticulum-released Ca2+. SKF96365 promoted cell mortality, inhibited colony formation, and induced apoptosis and cell-cycle arrest, while blunting the EGF-evoked Ca2+ signaling. Furthermore, we confirmed that SKF96365 reduced NPC xenograft growth while activating caspase-7-related apoptotic pathway. Conclusion SKF96365 exerts multiple antitumor activities through the distraction on the oncogenic Ca2+ signaling transduction in NPC cells.

GP73 level determines chemotherapeutic resistance in human hepatocellular carcinoma cells

Objective GP73 is a new hepatocellular carcinoma (HCC) marker, which is highly expressed in hepatocellular carcinoma and closely relates to prognosis. This study was to investigate the effects of GP73 on cellular proliferation, apoptosis, oxaliplatin (OXA) resistance and secretory clusterin (sCLU) of HCC cells. Materials and Methods Western blot and immunofluorescence was used to detect the expression of GP73 in 8 types of commonly used HCC cell lines. Drug resistance was induced by increasing concentration gradient method. The drug-resistant human HCC cell lines underwent GP73 overexpression or inhibition. Flow cytometry were used to detect the proliferation and apoptosis of HCC cell lines. The changes of sCLU were detected by enzyme-linked immunosorbent assay (ELISA). Results The expression of GP73 in MHC-97H cells was the highest and in Hep3B cells the lowest. The expression of GP73 was found further elevated in OXA-resistant MHC-97H cells. After the knockdown of GP73 in OXA-resistant 97H cells, the IC50 of OXA decreased and the ability of cell proliferation decreased significantly. After over-expression of GP73 in OXA-resistant Hep3B cells, the IC50 of OXA increased and the cell proliferation ability increased, showing that GP73 is critical for OXA resistant in HCC cell lines; No significant change of sCLU level in GP73 overexpressed Hep3B and GP73 blocked MHCC-97H were identified. Conclusion The expression level of GP73 is critical for the resistance of OXA in HCC cell lines.

The clinical significance and biological function of large tumour suppressor 2 in hepatocellular carcinoma

Present evidence has suggested that large tumour suppressor 2 (LATS2) is abnormally expressed in most human cancer. However, the clinical and prognostic value in hepatocellular carcinoma (HCC) is still unknown.

Clinical efficacy of bevacizumab concomitant with pemetrexed in patients with advanced non-small cell lung cancer.

OBJECTIVE To observe the clinical efficacy of bevacizumab concomitant with pemetrexed in patients with advanced non-small cell lung cancer (NSCLC). MATERIALS AND METHODS A total of 72 patients were randomly divided into a combination group (pemetrexed+bevacizumab, n=36) and a pemetrexed group (n=36) and assessed for disease control (CR+PR+SD) after 4-cycles of first-line GP chemotherapy (gemcitabine+cisplatin). Clinical efficacy, progression-free survival time (PFS), overall survival time (OS), overall response rate (ORR), disease control rate (DCR) and rate of adverse responses between two groups were observed and compared. RESULTS ORR and DCR were 27.8% and 83.4% in combination group, and 16.7% and 69.5% in the pemetrexed group, respectively, but there were no significant differences (P>0.05). PFS in combination group and pemetrexed group were 4.6 months and 3.9 months respectively (P=0.09), whereas OS in the combination group was 14 months, evidently higher than in the pemetrexed group (11 months, P=0.004). Adverse responses in both groups included high blood pressure, bleeding, thrombocytopenia, anemia, elevated transaminase, diarrhea, vomiting and proteinuria, but there were no significant differences (P>0.05). CONCLUSIONS Bevacizumab concomitant with pemetrexed has better clinical efficacy and safety, giving rise to prolonged survival time in patients with advanced NSCLC.

Blockage of store-operated Ca 2+ entry antagonizes Epstein–Barr virus-promoted angiogenesis by inhibiting Ca 2+ signaling-regulated VEGF production in nasopharyngeal carcinoma

Background Epstein–Barr virus (EBV) actively contributes to the pathological process of nasopharyngeal carcinoma (NPC) by enabling NPC cells to acquire various capacities required for their malignant biological actions. Our earlier works demonstrated that EBV-encoded latent membrane protein 1 (LMP1) enhanced vascular endothelial growth factor (VEGF)-mediated angiogenesis by boosting store-operated Ca2+ entry (SOCE) upon extracellular epidermal growth factor (EGF) stimulation. However, the antagonistic effects of SOCE blockage on EBV-promoted angiogenesis must be appropriately evaluated in vivo, and the global effect of EBV infection on the EGF-elicited cytosolic Ca2+ signaling, which regulates VEGF-mediated angiogenesis remains to be further clarified. Materials and methods Two EBV-infected NPC cell lines, CNE2-EBV and HK1-EBV, along with their parental cell lines were employed in the present study. Dynamic cytosolic Ca2+ changes were measured in individual fluorescent Ca2+ indicator-loaded cells. Amounts of VEGF production were determined by enzyme-linked immunosorbent assay (ELISA). Human umbilical vein endothelial cells (HUVECs)-formed tube networks were quantitatively evaluated as an in vitro angiogenesis assay. A mouse model concurrently bearing EBV-positive/negative xenografts was utilized to evaluate the tumor growth and angiogenesis in vivo. Results EBV infection reliably promoted transplanted tumor growth while enhancing angiogenesis. Introduction of EBV into EBV-negative NPC cells increased the EGF-stimulated VEGF production while amplifying the EGF-evoked Ca2+ responses. Inhibition of the EBV-boosted Ca2+ signaling using 2-aminoethyl diphenylborinate (2-APB), a specific SOCE inhibitor, effectively antagonized the EBV-promoted VEGF production and endothelial tube formation in vitro. Pharmacological blockage of SOCE exhibited anti-angiogenic effect in the EBV-positive xenografts. Conclusion SOCE can serve as a candidate pharmacological target for treating NPC, as blockage of the Ca2+ signaling via SOCE is a feasible strategy to suppress the EBV-driven malignant profiles in NPC cells.

Identification of Candidate Biomarkers in Malignant Ascites from Patients with Hepatocellular Carcinoma by iTRAQ-Based Quantitative Proteomic Analysis

Almost all the patients with hepatocellular carcinoma (HCC) at advanced stage experience pathological changes of chronic liver cirrhosis, which generally leads to moderate ascites. Recognition of novel biomarkers in malignant ascites could be favorable for establishing a diagnosis for the HCC patients with ascites, and even predicting prognosis, such as risk of distant metastasis. To distinguish the proteomic profiles of malignant ascites in HCC patients from those with nonmalignant liver cirrhosis, an iTRAQ pipeline was built up to analyze the differentially distributed proteins in the malignant ascites from HCC patients (n=10) and benign ascites from hepatic decompensation (HD) controls (n=9). In total, 112 differentially distributed proteins were identified, of which 69 proteins were upregulated and 43 proteins were downregulated (ratio <0.667 or >1.3, respectively) in the malignant ascites. Moreover, 19 upregulated proteins (including keratin 1 protein and rheumatoid factor RF-IP20, ratio>1.5) and 8 downregulated proteins (including carbonic anhydrase 1, ratio<0.667) were identified from malignant ascites samples. Functional categories analyses indicated that membrane proteins, ion regulation, and amino acid metabolism are implicated in the formation of HCC malignant ascites. Pathways mapping revealed that glycolysis/gluconeogenesis and complement/coagulation cascades are the mostly affected cell life activities in HCC malignant ascites, suggesting the key factors in these pathways such as Enolase-1 and fibrinogen are potential ascitic fluid based biomarkers for diagnosis and prognosis for HCC.

APE1 overexpression is associated with poor survival in patients with solid tumors: a meta-analysis

APE1 is known as a key mediator of DNA damage repair pathways, and its clinical significance in different types of cancer is well studied. Herein, we performed a meta-analysis to determine the association of APE1 expression and survival in different types of solid cancer. We searched all eligible publications in PubMed, Web of Science and Embase platforms from inception to January 2017 and found 15 relevant manuscripts. Overall survival (OS), 12- and 36-month survival rates, and hazard ratios (HRs) were extracted and analyzed. Heterogeneity and publication bias were also assessed. A subgroup analysis of the different subcellular locations of APE1 was also conducted. Patients with higher APE1 levels demonstrated lower 12- and 36-month survival rates than those with low APE1 levels (HR 2.00, 95% CI 1.33–3.00, P = 0.0009; HR 1.84, 95% CI 1.19–2.84, P = 0.006). Importantly, the pooled analysis showed that high levels of APE1 predict shorter OS (HR 1.44, 95% CI 1.13–1.83, P = 0.003). Subgroup analysis revealed that both nuclear and cytoplasmic expression levels of APE1 are important indicators of poor prognosis in solid tumors.

High expression of RBM8A predicts poor patient prognosis and promotes tumor progression in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a huge threat for human health worldwide. As a complicated tumor, the molecular basis for HCC development especially metastasis requires exploration. Although RNA binding motif (RBM) proteins are closely related to various cancers, the clinical importance and underlying mechanisms of RBM8A in HCC remain elusive. In this study, we found that RBM8A was highly expressed in HCC tumor tissues compared to normal liver tissues. Overexpression of RBM8A was associated with HbsAg and Edmondson pathological grading. Moreover, Kaplan-Meier survival analysis showed that high expression of RBM8A was related to the poor overall survival and progression-free survival of patients with HCC. Gain- and loss-of-function experiments further demonstrated that RBM8A promoted tumor cell migration and invasion in HCC via activation of epithelial-mesenchymal transition signaling pathway. It is also noteworthy that RBM8A is required for tumor cell proliferation and anti-apoptosis in HCC. Altogether, our results revealed a close relationship between RBM8A and HCC prognosis as well as a critical tumor-promoting function of RBM8A in HCC progression, suggesting that RBM8A might be a potential bio-marker and drug target in HCC therapy.

The hepatoprotective role of reduced glutathione and its underlying mechanism in oxaliplatin-induced acute liver injury

Currently, the underlying mechanism of oxaliplatin (OXA) induced live injury is unclear. In addition, there is no standard clinical treatment for OXA-induced acute liver injury (ALI). In this study, we established an animal model of OXA-induced ALI, and studied the role of oxidative stress in OXA-induced ALI and the impacts of reduced glutathione (GSH) treatment on OXA-induced ALI. To establish an OXA-induced ALI model, KM mice received intraperitoneal injection of OXA (8 mg/kg) for 4 days. Serum alanine aminotransferase (ALT), aspartate aminotransferase levels (AST), hepatic pathology and oxidative stress indicators in liver tissues were analyzed. To study the impact of GSH treatment on OXA-induced ALI, mice were treated with GSH (400 mg/kg, i.p). In this ALI mouse model, ALT and AST levels were significantly increased (P<0.01). Liver pathological examination revealed varying degrees of liver cell turbidity and degeneration, even balloon-like changes and focal necrosis, and sinusoidal hemorrhage in some cells. Compared with control group, the malondialdehyde (MDA) and GSH levels were significantly increased in OXA-treated group (P<0.01), while the superoxide dismutase SOD and GSH-peroxidase levels were decreased after OXA withdrawal (P<0.01). When GSH was used to treat OXA-induced ALI mice, the pathological injury of liver tissues was alleviated, and serum ALT and AST were significantly decreased. In addition, GSH treatment could reduce the OXA-induced increase of MDA level (P<0.05) in liver tissues, but had no impact on SOD level (P>0.05). We have successfully established an OXA-induced ALI model. Using this model, we discover that oxidative stress plays an important role in OXA-induced ALI. GSH-based hepatoprotective therapy can partially inhibit oxidative stress and alleviate OXA-induced ALI.

Seven-day capecitabine plus docetaxel and oxaliplatin regimen for the treatment of advanced gastric cancer: A phase-I clinical trial

Docetaxel, cisplatin and 5-fluorouracil (DCF regimen) are currently applied as an effective combination treatment for various human malignancies; however, the efficacy of this regimen is impaired by severe adverse events associated with it. Therefore, better-tolerated regimens with comparable efficiency are required for patients with gastric cancer. To explore such possibilities, a phase-I clinical trial was performed to evaluate the safety and tolerability of a modified regimen replacing cisplatin and 5-fluorouracil with oxaliplatin and capecitabine, respectively (DOX program). The maximum-tolerated dose (MTD) and dose-limited toxicity (DLT) of capecitabine in this regimen were determined and a dose for subsequent phase-II clinical trials was identified. A total of 24 patients with advanced gastric cancer were sequentially enrolled in the present capecitabine dose-escalation trial. The patients were treated with docetaxel and oxaliplatin at fixed doses [75 and 100 mg/m2, respectively, intravenously, on day 1 (d1)], and with capecitabine at increasing doses (1,500, 2,000 and 2,500 mg/m2, per os, d1-7). The MTD of capecitabine was 2,000 mg/m2 (d1-7), repeated every 21 days for at least two cycles. The most frequent DLTs for this regimen were leukopenia (15/24, 62.5%, all at grade-III/IV) and neutropenia (13/24, 54.2%, all at grade-III/IV), nausea (14/24, 58.3%, all at grade-III) and vomiting (13/24, 54.2%, all at grade-III). The effective rate of the DOX regimen was 75.0% (18/24). Based on the results, the combination of docetaxel (75 mg/m2, d1), oxaliplatin (100 mg/m2, d1) and capecitabine (2,000 mg/m2, d1-7) is recommended for a future phase-II trial. While these doses for the DOX regimen were generally well tolerated, the efficacy of this modified regimen in patients with advanced gastric cancer remains to be further evaluated in subsequent phase-II trials.