Interaction between Colon Cancer Cells and Human Liver Sinusoidal Endothelial Cells Promotes Liver Metastasis of Tumor Cells

OBJECTIVE To investigate the effect of co-culture between colon cancer cells （SW1116） and human liver sinusoidal endothelial cells （HLSECs） on cancer cell metastasis, and to provide a novel model for studying the mechanism of colon cancer liver metastasis. METHODS HLSECs and SW1116 were co-cultured for 21 rounds in vitro. Transwell migration, gelatin-zymography, CCK-8 proliferation and colony formation assays were used to examine the invasion, proliferation, and colony forming ability of cancer cells. Assays were carried out to examine tumor growth ability and liver metastasis. The associated molecular change was examined by western blotting. RESULTS After 21 selection rounds, colon cancer cells SWl 1161）21 displayed a clear boundary. Compared with the 5W1116 cells, SW1116P21 cells had a greater invasive ability, cell proliferation and colony formation in soft agar. A gelatin-zymography assay showed that the ability of SW1116P21 cells to secrete matrix metalloproteinase-2/9 was significantly greater than that of SWl116 cells. Additionally, the capacity for subcutaneous tumor formation of SW1116P21 was significantly increased. It was found that mice injected with SW1116P21 cells developed significantly more visually observable liver nodules than mice injected with SW1116 cells. Western blotting showed increased vimentin expression and decreased E-cadherin expression in the SW1116P21 cells, compared with the SWl 116 cells. CONCLUSION The interaction between SW1116 and HLSECs may promote tumor cell invasion, proliferation and colony formation in vitro, and tumor formation and liver metastasis in vivo. An epithelial-mesenchymal transition occurs in SWl 116P21 cells, which contributes to the change in the characteristics of tumor cells.

Efficient generation of functional hepatocytelike cells from mouse liver progenitor cells via indirect co-culture with immortalized human hepatic stellate cells

BACKGROUND： Differentiation of liver progenitor cells（LPCs） to functional hepatocytes holds great potential to develop new strategies for hepatocyte transplantation and the screening of drug-induced cytotoxicity. However, reports on the efficient and convenient hepatic differentiation of LPCs to hepatocytes are few. The present study aims to investigate the possibility of generating functional hepatocytes from LPCs in an indirect co-culture system.METHODS： Mouse LPCs were co-cultured in Transwell plates with an immortalized human hepatic stellate cell line（HSCLi） we previously established. The morphology, expression of hepatic markers, and functions of mouse LPC-derived cells were monitored and compared with those of conventionally cultured LPCs. RESULTS： Co-culturing with HSC-Li cells induced differentiation of mouse LPCs into functional hepatocyte-like cells. The differentiated cells were morphologically transformed into hepatocyte-like cells 3 days after co-culture initiation. In addition, the differentiated cells expressed liver-specific genes and possessed hepatic functions, including glycogen storage, lowdensity lipoprotein uptake, albumin secretion, urea synthesis, and cytochrome P450 1A2 enzymatic activity.CONCLUSIONS： Our method, which employs indirect co-culture with HSC-Li cells, can efficiently induce the differentiation of LPCs into functional hepatocytes. This finding suggests that this co-culture system can be a useful method for the efficient generation of functional hepatocytes from LPCs.

Malignant Transformation of Human Embryonic Liver Cells Induced by Hepatitis B Virus and Aflatoxin B_1

In order to investigate the effect of hepatitis B virus (HBV) and aflatoxin B 1 (AFB 1) on hepatocarcinogenesis, the human embryonic liver cells infected with HBV were transplanted to nude mice by subcutaneous route and the transplanted mice were divided into 4 groups for study, in which the group A of mice was injected with HBV-infected human embryonic liver cells and followed by injections of AFB 1 once a week (HBV+AFB 1); the group B was treated with HBV as group A, but no AFB 1 was given (HBV +); the group C was injected with normal human embryonic liver cells and AFB 1 was used as group (AFB 1 +) and the group D or control group was injected with normal embryonic liver cells without addition of AFB 1. The experimental results showed that the incidences of tumor formation in different groups were 27.3% (6/22) in group A; 0% (0/13) in group B; 13.3% (2/15) in group C and 0% (0/14) in group D respectively. All the tumors formed were proved to be human hepatocellular carcinoma (HCC) by pathological examinations and the tumor tissues were anthrogenetic as demonstrated by EMA monoclonal antibody. The HBV-X and HBV-S genes could be detected in the tumor tissues by means of slot hybridization and PCR amplification, indicating that the HBV-DNA genes had integrated into DNA of host cells. Thus, we have successfully induced the human HCC through HBV infection and introduction of AFB 1 with a synergistic effect between HBV and AFB 1 in hepatocarcinogenesis.

Using a non-radioisotopic, quantitative TRAP-based method detecting telomerase activities in human hepatoma cells

A non-radioisotopic, quantitative TRAP-based telomerase activity assay was established mainly by using SYBR Green-I staining instead of radioisotope. Comparing with conventional radioisotope based method, it was better in reproducibility and accuracy. Using this method, we found telomerase activities were absent in normal human liver cells, while detected in ail of four human hepatoma cell lines (BEL-7404, SMMC-7721, QGY-7903 and HCCM) without significant differences.

Hybrid bioartificial liver support in cynomolgus monkeys with D-galactosamine-induced acute liver failure

AIM: To evaluate a hybrid bioartificial liver support system (HBALSS) in cynomolgus monkeys with acute liver failure.

A novel animal model for in vivo study of liver cancer metastasis

AIM:To establish an animal model with human hepatocyte-repopulated liver for the study of liver cancer metastasis.METHODS:Cell transplantation into mouse livers was conducted using alpha-fetoprotein(AFP)-producing hu-man gastric cancer cells(h-GCCs) and h-hepatocytes as donor cells in a transgenic mouse line expressing urokinase-type plasminogen activator(uPA) driven by the albumin enhancer/promoter crossed with a severe combined immunodeficient(SCID) mouse line(uPA/SCID mice).Host mice were divided into two groups(A and B).Group A mice were transplanted with h-GCCs alone,and group B mice were transplanted with h-GCCs and h-hepatocytes together.The replacement index(RI),which is the ratio of transplanted h-GCCs and h-hepatocytes that occupy the examined area of a histological section,was estimated by measuring h-AFP and h-albumin concentrations in sera,respectively,as well as by immunohistochemical analyses of h-AFP and human cytokeratin 18 in histological sections.RESULTS:The h-GCCs successfully engrafted,repopulated,and colonized the livers of mice in group A(RI = 22.0% ± 2.6%).These mice had moderately differentiated adenocarcinomatous lesions with disrupted glandular structures,which is a characteristics feature of gastric cancers.The serum h-AFP level reached 211.0 ± 142.2 g/mL(range,7.1-324.2 g/mL).In group B mice,the h-GCCs and h-hepatocytes independently engrafted,repopulated the host liver,and developed colonies(RI = 12.0% ± 6.8% and 66.0% ± 12.3%,respectively).h-GCC colonies also showed typical adenocarcinomatous glandular structures around the h-hepatocyte-colonies.These mice survived for the full 56 day-study and did not exhibit any metastasis of h-GCCs in the extrahepatic regions during the observational period.The mice with an h-hepatocyte-repopulated liver possessed metastasized h-GCCs and therefore could be a useful humanized liver animal model for studying liver cancer metastasis in vivo.CONCLUSION:A novel animal model of human liver cancer metastasis was established using the uPA/SCID mouse line.This model could be useful for in vivo testing of anti-cancer drugs and for studying the mechanisms of human liver cancer metastasis.

PRIMARY STUDY ON MECHANISM OF COLLAGEN SYNTHESIS INHIBITION IN CULTURED HUMAN FETAL HEPATOCYTES PRETREATED BY SALVIA MILTIORRHIZA BUNGE

Objective The effects of salvia miltiorrhiza bunge (SMB) on collagen synthesis in the human fetal hepatocytes culture were studied. Methods The collagen synthesis of hepatocytes were stimulated by the addition of carbon tetrachloride (CCl 4 ) to the culture medium, the concentration of type procollagen (PC) in the culture medium and the hydroxyproline (Hyp) in hepatocytes were determined, as well as the activity of se dependent glutathione peroxidase (Se GSH Px) and the concentration of malondiadehyde (MDA) in the culture medium. Results A significant decrease in PC, Hyp and MDA production, and the significant increase in Se GSH Px activity were observed in the cultures pretreated with 1 g L -1 SMB for 4 hours compared with the untreated cultures. Analysis of the Se GSH Px/MDA ratio in SMB pretreated group showed more marked increase compared to that of the untreated group ( P <0.01). There was a significant negative correlation between the ratio of Se GSH Px/MDA and the concentration of PC in SMB pretreated group ( r=-0.9017, P <0.01). Conclusion Our results indicate that SMB may suppress the collagen synthesis of cultured human fetal hepatocytes stimulated by CCl 4 , and its mechanism may be related to the increase in Se GSH Px/MDA ratio and the enhancement of hepatocytes antioxidation capability.

Chimera formation of platelet GPⅡb Bak a/b by intrauterine transplantation of fetal liver stem cells

Abstract:Objective To investigate whether artificial heterozygous chimeras of platelets can be established by intrauterine transplantation of fetal liver stem cells and evaluate its potential use for the treatment of Glanzmann thrombasthenia.Methods Platelet glycoprotein (GP) Ⅱb Bak a/b (or GPⅡb Ⅰle843Ser) was used as a genetic marker. A homozygous 16-week-old Bak a/a fetus (as donor) and a homozygous 16.5-week-old Bak b/b fetus (as recipient) were screened from 42 pregnant women hospitalized for abortion. PCR with allele specific primers and FOK Ⅰ digestion based on PCR products were used. Aborted donor fetal liver cell suspensions were prepared and intrauterine transplantation was carried out by infusion of 4?ml fetal liver cells (22×105) into the recipient umbilical vein under ultrasonic visualization.Results At gestation termination (abortion), 21 days after transplantation, chimera GPⅡb Bak a/b of the recipient were detected by FOK 1 digestion based on PCR from DNA and RT-PCR from platelet RNA. Conclusion Intrauterine transplantation of fetal liver cell may provide an effective way for curing GT or other inherited diseases.