Zhengyan Zhu

Tumor-Infiltrating FoxP3+ Tregs and CD8+ T Cells Affect the Prognosis of Hepatocellular Carcinoma Patients

Purpose: Tumor-infiltrating lymphocytes are considered to represent a host immune response against tumor. This study was carried out to analyze the effect of both FoxP3+ regulatory T cells (Tregs) and CD8+ T lymphocytes in prognostic value of hepatocellular carcinoma (HCC) patients. Methods: Expressions of FoxP3, CD4, CD8 and CD34 in patient-matched tumors and peritumoral tissues were assessed by immunohistochemistry for 54 HCC patients. The prognostic effect of groups with high and low numbers was evaluated by the Kaplan-Meier and Cox model analysis using median values as a cutoff. Results: Compared with the corresponding peritumoral tissue, the density of intratumoral Tregs was significantly higher, while the density of intratumoral CD8+ T cells was lower (p < 0.001 and p = 0.013, respectively). In addition, tumor-infiltrating Tregs were positively correlated with microvessel density in tumors (r = 0.334, p = 0.020). The high intratumoral Tregs density group showed a significantly lower survival rate (overall survival, p = 0.018; disease-free survival, p = 0.029). Multivariate Cox analysis revealed that intratumoral Tregs density was an independent prognostic factor for HCC. Conclusions: Tumor-infiltrating Tregs may promote HCC progression by fostering angiogenesis and decreasing CD8+ T cells. High tumor-infiltrating Tregs are thought to be an unfavorable prognostic indicator for HCC.

Foxp3+ regulatory T cells are associated with the natural history of chronic hepatitis B and poor prognosis of hepatocellular carcinoma

Recent studies have focused on regulatory T cells (Tregs) in chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) and they were also conducted independently of each other.

Intrahepatic interleukin-17+ T cells and FoxP3+ regulatory T cells cooperate to promote development and affect the prognosis of hepatocellular carcinoma.

Recent studies have shown that imbalance between tumor‐infiltrating interleukin (IL)‐17+ T cells and regulatory T cells (Tregs) is an important regulator of progression in various cancers, but little is known regarding this imbalance in hepatocellular carcinoma (HCC). This study explored the role of imbalance between IL‐17+ T cells and Tregs in the immunopathogenesis of HCC in patients with chronic hepatitis B (CHB) infection.

Extracellular domain of human 4-1BBL enhanced the function of cytotoxic T-lymphocyte induced by dendritic cell.

Interaction of costimulatory molecules and their receptors is crucial for tumor lysate-pulsed dendritic cells (sensitized DC, sDC) to promote T cell activation, clonal expansion and its antitumor immunity. To augment the costimulatory signal may regulate the interaction between DC and cytotoxic T lymphocyte (CTL) and consequently enhance the antitumor response. The costimulatory ligand and receptor pair of 4-1BB/4-1BBL is one of the main factors in the costimulation of CTL. We explored the adjuvant role of a recombinant human 4-1BBL extracellular domain (ex4-1BBL) in modulating CTL activation induced by HepG2 antigen-loaded DC (sDC). The augment effects of sDC in combination with ex4-1BBL on the proliferation, activation, cell survival and cytotoxicity against HepG2 cells of CTL were examined. In the presence of ex4-1BBL, sDC exhibited markedly augmented effects on the above four functions of CTL. These results demonstrate that ex4-1BBL plays an important role in the costimulation pathway for DC-mediated CTLs activation, which might be a useful adjuvant factor for DC-based cancer biotherapy.

The subtype CD200-positive, chorionic mesenchymal stem cells from the placenta promote regeneration of human hepatocytes

Abstract Human placental mesenchymal stem cells (hPMSCs), for the treatment of fulminant hepatic failure, have been widely studied. Only a few studies have investigated the effect of the subtype CD200+hPMSCs on regeneration of human hepatocytes. CD200+hPMSCs can down-regulate activity of several immunocytes and suppress TNF-α secretion from macrophages via the CD200-CD200R axis. We have investigated the influence of CD200-positive human placenta chorionic mesenchymal stem cells (CD200+hPCMSCs) on metabolism, proliferation and apoptosis of human hepatocytes in vitro. CD200+hPCMSCs promote urea synthesis, albumin secretion and hepatocytes proliferation at co-culture ratios of 1:1 and 3:1. Additionally, CD200+hPCMSCs inhibit hepatocyte apoptosis via up-regulation of an anti-apoptotic protein, Bcl-xL. Thus, CD200+hPCMSCs can provide supportive benefit for the regeneration of human hepatocytes and also have immunosuppressive properties. Therefore, CD200+hPCMSCs may be an ideal candidate for stem cell-based therapy in hepatic failure.

Comparative study of different procedures for the separation of peripheral blood mononuclear cells in cytokine-induced killer cell immunotherapy for hepatocarcinoma

Cytokine-induced killer (CIK) cell immunotherapy exhibits significant advantages in the clinical treatment of tumors. This study was designed to compare the biological characteristics of autologous CIK cells from patients with hepatocarcinoma following different procedures for the separation of peripheral blood mononuclear cells (PBMCs). Forty-four hepatocarcinoma patients were enrolled and distributed into two groups. PBMCs were isolated either using a blood cell separator (apheresis method) or Ficoll lymphocyte separation medium (Ficoll method). The total amount, collection efficacy, and cell status of PBMCs in the two groups were determined. According to the number and status of collected PBMCs, different cultivation procedures were used for their amplification and activation and the proliferation ability, phenotype, and killing activity of CIK cells in the two groups were evaluated. Our results indicated that the number of collected PBMCs in the apheresis group was far more than that in the Ficoll group. However, the isolation rate was lower, and more cellular debris was observed in the apheresis group, which may be the cause of some untoward effects. Following in vitro culture, the enrichment time of CIK cells was longer in the Ficoll group, and the percentages of CD3+CD4+ (Th) and CD4+CD25+ (Treg) cells were higher. In the apheresis group, the percentages of CD3−CD56+ (NK) and CD3+CD56+ (NKT) cells were higher, and the CIK cells exhibited a higher cytolytic activity against HepG2 hepatoma cells. In conclusion, different procedures for PBMCs separation can influence the biological activities of CIK cells, and the apheresis method is more effective at enhancing the antitumor efficacy of CIK cells. However, significant attention should be paid to the possibility of adverse reactions in apheresis donors.

Hepatectomised patient sera promote hepatocyte differentiation of human-induced pluripotent stem cells

BACKGROUND Human induced pluripotent stem cells, which can be differentiated into hepatocyte-like cells, could provide a source for liver regeneration and bio-artificial liver devices. However, the functionality of hepatocyte-like cells is significantly lower than that of primary hepatocytes. AIMS To investigate whether serum from patients undergoing hepatectomy might promote differentiation from human induced pluripotent stem cells to hepatocyte-like cells. METHODS Serum from patients undergoing hepatectomy (acquired pre-hepatectomy and 3 hours, 1 day and 3 days post-hepatectomy) was used to replace foetal bovine serum when differentiating human induced pluripotent stem cells into hepatocyte-like cells. Properties of hepatocyte-like cells were assessed and compared with cells cultured in foetal bovine serum. RESULTS The differentiation efficiency and functionality of hepatocyte-like cells cultured in human serum 3 hours and 1 day post-hepatectomy were superior to those cultured in foetal bovine serum and human serum pre-hepatectomy. Human serum 3 days post-hepatectomy had an equal effect to that of human serum pre-hepatectomy. Some cytochrome P450 isozyme transcript levels of hepatocyte-like cells cultured in human serum were higher than those cultured in foetal bovine serum. CONCLUSION Human serum, particularly that acquired relatively soon after hepatectomy, can enhance the differentiation efficiency and functionality of hepatocyte-like cells derived from human induced pluripotent stem cells.

Three-dimensional hydrogel culture conditions promote the differentiation of human induced pluripotent stem cells into hepatocytes

BACKGROUND AIMS Human induced pluripotent stem cells (hiPSCs) are becoming increasingly popular in research endeavors due to their potential for clinical application; however, such application is challenging due to limitations such as inferior function and low induction efficiency. In this study, we aimed to establish a three-dimensional (3D) culture condition to mimic the environment in which hepatogenesis occurs in vivo to enhance the differentiation of hiPSCs for large-scale culture and high throughput BAL application. METHODS We used hydrogel to create hepatocyte-like cell (HLC) spheroids in a 3D culture condition and analyzed the cell-behavior and differentiation properties of hiPSCs in a synthetic nanofiber scaffold. RESULTS We found that treating cells with Y-27632 promoted the formation of spheroids, and the cells aggregated more rapidly in a 3D culture condition. The ALB secretion, urea production and glycogen synthesis by HLCs in 3D were significantly higher than those grown in a 2-dimensional culture condition. In addition, the metabolic activities of the CYP450 enzymes were also higher in cells differentiated in the 3D culture condition. CONCLUSIONS 3D hydrogel culture condition can promote differentiation of hiPSCs into hepatocytes. The 3D culture approach could be applied to the differentiation of hiPSCs into hepatocytes for bioartificial liver.

Metabolic perturbation of epigenome by inhibiting S-adenosylhomocysteine hydrolase elicits senescence through DNA damage response in hepatoma cells

Cellular senescence is a key physiological barrier against tumor and represents an option for therapeutic intervention. One pivotal intracellular stimulus causing senescence is DNA damage response, while the senescence-associated heterochromatin in cancer limits the strength of the DNA damage response to endogenous genotoxic stress or DNA-damaging agents. Therefore, targeting the maintenance of compacted chromatin in cancer cells represents an optional intervention to improve the therapeutic efficacy in cancer treatment. Given a crosstalk between methionine cycle and histone methylation, we hypothesize that pharmacologically disrupting methylation potential, defined as the ratio of cellular S-adenosylmethionine to S-adenosylhomocysteine, could affect the chromatin structures in cancer cells and thus enhance their sensitivity to DNA damage response signaling. Our results showed that 3-deazaneplanocin A, a chemical inhibitor of S-adenosylhomocysteine hydrolase, elicited a typical cellular senescence in hepatoma cells. Therapy-induced senescence by 3-deazaneplanocin A was mediated through p53–p21 pathway and triggered by enhanced ataxia-telangiectasia mutated activation related to chromatin changes. In conclusion, our study demonstrated that metabolic perturbation of chromatin status in oncogene-activated cancers could be an optional intervention to sensitize DNA damage response signaling.