Tumoricidal activities of pterostilbene depend upon destabilizing the MTA1-NuRD complex and enhancing P53 acetylation in hepatocellular carcinoma.

The present study aimed to assess the tumoricidal effect of metastasis-associated protein 1 (MTA1) induced by pterostilbene (PTER) in hepatocellular carcinoma (HCC). The SMMC-7721 hepatoma cell line was treated with PTER. Following treatment, the mRNA transcript abundance of MTA1 was measured using quantitative polymerase chain reaction. Additionally, cell viability was determined using an MTT assay, and protein expression was measured through western blotting. Cell invasion, motility and apoptosis, as well as the cell cycle, were also investigated. Following PTER treatment, MTA1, histone deacetylase (HDAC) 1 and HDAC2 were downregulated, whereas the ratio of acetyl-p53 to total p53 was increased in HCC cells. Cell viability decreased as the PTER dose increased. MTA1 may be associated with proliferation, motility, invasion and metastasis in HCC cells. PTER appeared to repress cell proliferation, trigger apoptosis, induce cell cycle arrest, and inhibit motility and invasion via MTA1 in human liver cancer cells. The results of the present study demonstrated that PTER can downregulate the MTA1-nucleosome remodeling and deacetylase complex, and enhance p53 acetylation to inhibit the growth of tumor cells in HCC.

Inhibition of hepatocelluar carcinoma MAT2A and MAT2beta gene expressions by single and dual small interfering RNA.

RNA interference (RNAi) has been successfully applied in suppression of hepatic cancer genes. In hepatocelluar carcinoma cell, one methionine adenosyltransferase (MAT) isozyme, MATII was found to have two catalytic subunits which were encoded by MAT2A and MAT2beta respectively. During tumorigeness of hepatocelluar carcinoma, expressions of the two genes were discovered to be increased combining with a switch of MAT (form MATI to MATII), To figure out the role played by MATII in hepatic cancer, In this study, for the first time we established a dual small interfering RNA (siRNA) expression system, which could simultaneously express two different siRNA molecules specifically targeting two genes. To test the effectiveness of this system, we applied this approach to express simultaneously two different siRNA duplexes that specifically target MAT2A and MAT2beta genes of hepatocelluar carcinoma respectively in HepG2 cell. Results indicated that dual siRNA could simultaneously inhibit the expression of MAT2A and MAT2beta gene by 89.5% and 97.8% respectively, In addition, dual siRNA molecules were able to significantly suppress growth of hepatocelluar carcinoma cell in vitro as well as induce apoptosis which was involved in arrest cell cycle at the G1/S checkpoint and the expressions of p21, p27 and Bax.

Treatment of upper gastrointestinal fistula and leakage with personal stage nutrition support.

AIM: To investigate the feasibility of treatment for upper gastrointestinal fistula and leakage with personal stage nutrition support. METHODS: Forty-three patients with upper gastrointestinal fistula and leakage were randomly divided into two groups. Patients in group A were treated with personal stage nutrition support and patients in group B were treated with total parental nutrition (TPN) in combination with operation. Nutritional states of the candidates were evaluated by detecting albumin (Alb) and pre-Alb. The balance between nutrition and hepatic function was evaluated by measurement of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin (Tbill) before and after operation. At the same time their complications and hospitalized time were surveyed. RESULTS: Personal stage nutrition support improved upper gastrointestinal fistula and leakage. The nutrition state and hepatic function were better in patients who received personal stage nutrition support than in those who did not receive TPN. There was no significant difference in the complication and hospitalized time in the two groups of patients. CONCLUSION: Upper gastrointestinal fistula and leakage can be treated with personal stage nutrition support which is more beneficial for the post-operation recovery and more economic than surgical operation.

Lentivirus mediated shRNA interference targeting MAT2B induces growth-inhibition and apoptosis in hepatocelluar carcinoma.

AIM: To investigate the effects of lentivirus vector mediated short hairpin RNA interference targeting methionine adenosyltransferase 2beta gene (LV-shMAT2B) on hepatocelluar carcinoma (HCC) cells. METHODS: We constructed four plasmids of RNA interference targeting the MAT2B gene. After LV-shMAT2B was transfected with L-02 cells and two kinds of HCC cells, cell viability and proliferation were measured with MTT and [3H]thymidine assays respectively. Flow cytometry was used to assess cell apoptosis. The level of S-adenosyl methionine (SAMe) in HepG2 cells was evaluated. The expressions of cyclin D1, cyclin D2, bcl-x(L) and bcl-x(S) were detected with western blot. RESULTS: We constructed LV-shMAT2B successfully. LV-shMAT2B was safe for human normal liver cells. LV-shMAT2B caused dramatic reduction in proliferation compared with controls in HCC cells Bel-7402 (P = 0.054) and HepG2 (P = 0.031). Flow cytometry analysis showed that cell apoptosis caused by LV-shMAT2B was greater in HCC cells Bel-7402 and HepG2 than in control induced by scrambled siRNA (P = 0.047), but apoptosis rates in L-02 induced by LV-shMAT2B and scrambled siRNA respectively had no significant difference. Moreover, LV-shMAT2B significantly suppressed expression of MAT2B leading to growth-inhibition effect on HCC cells by down-regulating cyclin D1. Apoptosis induced by LV-shMAT2B was involved in down-regulating bcl-x(L) and up- regulating bcl-x(S). CONCLUSION: LV-shMAT2B can induce cell apoptosis and growth-inhibition in HCC cells. MAT2B may be a therapy target in HCC in the future.

Expression of angiopoietin-2 is correlated with vascularization and tumor size in human colorectal adenocarcinoma.

Angiopoietins are endothelial growth factors, which play crucial roles in normal vascular development and tumor angiogenesis. We examined the expression profiles of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), vascular endothelial growth factor (VEGF), and Tie-2, a receptor for Ang-1 and Ang-2, in both colorectal adenocarcinoma and adjacent normal tissues, as judged by histology, in order to elucidate their relationships with microvascular density (MVD) and clinicopathologic properties. Higher MVD was associated with a lower degree of differentiation of colorectal adenocarcinoma. Immunohistochemical analysis revealed that the expression of Ang-2 and VEGF was significantly increased in colorectal adenocarcinoma compared to adjacent normal tissues (p < 0.01), and the expression of Ang-2 positively correlated with that of VEGF (r = 0.997, p < 0.01). In contrast, the expression of Ang-1 was lower in adenocarcinoma tissues than in adjacent normal tissues (p < 0.01), while there was no significant difference in Tie-2 expression in both tissues. Moreover, MVD was increased in Ang-2- and VEGF-expressing adenocarcinoma tissues compared to the Ang-2- and VEGF-negative tissues, respectively (p < 0.01). Importantly, MVD was lower in Ang-1-expressing adenocarcinoma tissues relative to Ang-1-negative tissues (p < 0.01). Furthermore, expression of Ang-2 as well as VEGF was significantly up-regulated in colorectal adenocarcinoma with diameters > or = 5 cm or with lymph-node metastases (p < 0.01). In conclusion, the increased expression of Ang-2 and the decreased expression of Ang-1 may be responsible for blood vessel formation and rapid growth of the colorectal adenocarcinoma.

Effect of complex amino acid imbalance on growth of tumor in tumor-bearing rats.

AIM: To investigate the effect of complex amino acid imbalance on the growth of tumor in tumor-bearing (TB) rats. METHODS: Sprague-Dawley (SD) rats underwent jejunostomy for nutritional support. A suspension of Walker-256 carcinosarcoma cells was subcutaneously inoculated. TB rats were randomly divided into groups A, B, C and D according to the formula of amino acids in enteral nutritional solutions, respectively. TB rats received jejunal feedings supplemented with balanced amino acids (group A), methionine-depleted amino acids (group B), valine-depleted amino acids (group C) and methionine- and valine-depleted complex amino acid imbalance (group D) for 10 days. Tumor volume, inhibitory rates of tumor, cell cycle and life span of TB rats were investigated. RESULTS: The G0/G1 ratio of tumor cells in group D (80.5 +/- 9.0)% was higher than that in groups A, B and C which was 67.0 +/- 5.1%, 78.9 +/- 8.5%, 69.2 +/- 6.2%, respectively (P<0.05). The ratio of S/G2M and PI in group D were lower than those in groups A, B and C. The inhibitory rate of tumor in groups B, C and D was 37.2%, 33.3% and 43.9%, respectively (P<0.05). The life span of TB rats in group D was significantly longer than that in groups B, C, and A. CONCLUSION: Methionine/valine-depleted amino acid imbalance can inhibit tumor growth. Complex amino acids of methionine and valine depleted imbalance have stronger inhibitory effects on tumor growth.

Tamoxifen combined with octreotide or regular chemotherapeutic agents in treatment of primary liver cancer: a randomized controlled trial.

OBJECTIVE: To evaluate the effect of tamoxifen (TAM) combined with a somatostatin analogue, octretide (OCT) on advanced liver cancer and whether tamoxifen combined with OCT is superior to regular chemotherapeutic agents 5-Fu and mitomycin C (MMC). METHODS: Thirty-nine patients with inoperable liver cancer were randomly subdivided into TAM+OCT group (n=24) and regular chemotherapeutic group (n=15). They received treatment for three months respectively. Blood cell count, liver function, immunologic function, blood alpha-FP was regularly measured. Liver lump and extrahepatic metastasis were examined by CT. The patients were followed up after treatment and conducted survival analysis. RESULTS: In the TAM+OCT group, complete response is 4 patients, partial response is 7 patients, no change is 9 patients and progressive disease is 4 patients; blood level of ALT and AST had no noticeable change, IgE and IgG increased (P<0.01), and alpha-FP lowered (P<0.05). In regular chemotherapeutic group, no change is 4 patients and progressive disease is 11 patients. There was conspicuous statistical difference in the two groups. The accumulative survival rates of 6 months, 1 year and 2 years were 95.7% vs 41.2% (P<0.01), 63.7% vs 21.1% (P<0.01), 25.4% vs 0 (P<0.01), respectively. Medium survival time was 12.8 months in TAM+OCT group and 5.5 months in chemotherapeutic group. CONCLUSIONS: TAM+OCT excerts reliable therapeutic effect on patients with inoperable ER(+) hepatocellular cancer. It is superior to 5-Fu and MMC in increasing the survival rate, prolonging survival time, and reducing side-effects.

Toxicities and therapeutic effect of 5-fluorouracil controlled release implant on tumor-bearing rats.

AIM: To investigate the toxicities, biodistribution and anticancer effect of 5-fluorouracil controlled release implant (5-FUCI) on Walker 256 carcinosarcoma cells in Wistar rats. METHODS: Experiment 1: Wistar rats were randomly divided into three groups (27 rats per group). Blank implant was implanted in left lobe of the liver, and rats were treated with saline solution (in group A) or 5-fluorouracil (subcutaneous injection, group B). 5-FUCI was inserted in left lobe of the liver (group C). The gastrointestinal and hematological toxicities were observed and contents of element F in group C were assayed. Experiment 2: on day 6 after Walker-256 carcinosarcoma transplantation in left lobe of the liver, 5-FUCI was implanted in right lobe of the liver (group E) or left lobe (group F), and rats in control group (group D) were inserted blank implant. Tumor inhibition rate and survival time were investigated. RESULTS: 5-FUCI showed no obvious toxic effect, extraction of Evan's blue from gastrointestinal tissue was normal, the peripheral white blood cells and bone marrow nucleated cells were not reduced, compared with control group (P>0.05). Histological examination revealed that there were no visible changes in small intestinal mucosa, The concentration of 5-fluorouracil in left lobe of the liver was 9.84, 28, 34 times as much as those of right lobe of the liver, heart and kidney respectively after the implantation in group C. They kept a high level of fluorouracil in left lobe of the liver, ranging from (4.414+/-0.482) % to (7.800+/-0.804) %, for eight weeks. Survival days were 28.0+/-2.2, 30.0+/-3.2 and 38.7+/-6.7 d in group D, E and F, respectively. CONCLUSION: 5-FUCI shows no obvious toxicities to gastrointestinal tract and myelotoxicity. After implantation, it kept a high level of 5- fluorouracil in surrounding tissues of the implant for eight weeks. Its antitumor effect on Walker-256 carcinosarcoma is demonstrated.

Influence of methionine/valine-depleted enteral nutrition on nucleic acid and protein metabolism in tumor-bearing rats.

AIM: To investigate the effects of methionine/valine-depleted enteral nutrition (EN) on RNA, DNA and protein metabolism in tumor-bearing (TB) rats. METHODS: Sprague-Dawlley (SD) rats underwent jejunostomy for nutritional support. A suspension of Walker-256 carcinosarcoma cells was subcutaneously inoculated. 48 TB rats were randomly divided in 4 groups: A, B, C and D. The TB rats had respectively received jejunal feedings supplemented with balanced amino acids, methionine-depleted, balanced amino acids and valine-depleted for 6 days before injection of 740 KBq (3)H- methionine/valine via jejunum. The (3)H incorporation rate of the radioactivity into RNA, DNA and proteins in tumor tissues at 0.5, 1, 2, 4 h postinjection of tracers was assessed with liquid scintillation counter. RESULTS: Incorporation of (3)H into proteins in groups B and D was (0.500+/-0.020) % to (3.670+/-0.110) % and (0.708+/-0.019) % to (3.813+/-0.076) % respectively, lower than in groups A ((0.659+/-0.055) % to (4.492+/-0.108) %) and C ((0.805+/-0.098) % to (4.180+/-0.018) %). Incorporation of (3)H into RNA, DNA in group B was (0.237+/-0.075) % and (0.231+/-0.052) % respectively, lower than in group A (P<0.01). There was no significant difference in uptake of (3)H by RNA and DNA between group C and D (P>0.05). CONCLUSION: Protein synthesis was inhibited by methionine/valine starvation in TB rats and nucleic acid synthesis was reduced after methionine depletion, thus resulting in suppression of tumor growth.