Amphiregulin activates regulatory T lymphocytes and suppresses CD8+ T cell-mediated anti-tumor response in hepatocellular carcinoma cells

CD8⁺ T cell-mediated immune response plays an important role in inhibiting progression of hepatocellular carcinoma (HCC). For strategic immunotherapy, it is critical to understand why some of the tumor cells escape from this immune attack. In this study, we investigated how HCC cells alter endogenous anti-tumor immunity and their related signaling pathways. We found that HCC cells, both in vitro and in vivo, substantially secret and express amphiregulin (AR). AR in turn activates immunosuppressive function of intratumoral CD4⁺Foxp3⁺ regulatory T cells (Tregs), a major inhibitor of CD8⁺ T cells. Using either lentiviral siRNA, or AR neutralizing antibody, we blocked the expression and function of AR to test the specificity of AR mediated activation of Tregs, Biochemical and cell biology studies were followed and confirmed that blocking of AR inhibited Tregs activation. In addition, we found that AR can trigger the activation of rapamycin complex 1(mTORC1) signaling in Tregs. The mTORC1 inhibitor rapamycin treatment led to compromise Treg function and resulted in enhancing anti-tumor function of CD8⁺ T cells. Blocking AR/EGFR signaling in Tregs with Gefitinib also enhanced anti-tumor immunity and decreased tumor size in a mouse xenograft tumor model. Taken together, our study suggested a novel mechanism of functional interaction between HCC and Tregs for regulating anti-tumor function of CD8⁺ T cells.     

Innate immune cells and their interaction with T cells in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a malignant tumor and is associated with necroinflammation driven by various immune cells, such as dendritic cells, macrophages and natural killer cells. Innate immune cells can directly affect HCC or regulate the T-cell responses that mediate HCC. In addition, innate immune cells and T cells are not isolated, which means the interaction between them is important in the HCC microenvironment. Considering the current unsatisfactory efficacy of immunotherapy in patients with HCC, understanding the relationship between innate immune cells and T cells is necessary. In the present review the roles and clinical value of innate immune cells that have been widely reported to be involved in HCC, including dendritic cells, macrophages (including kupffer cells), neutrophils, eosinophils, basophils and innate lymphoid cells and the crosstalk between the innate and adaptive immune responses in the antitumor process have been discussed. The present review will facilitate researchers in understanding the importance of innate immune cells in HCC and lead to innovative immunotherapy approaches for the treatment of HCC.     

微波消融治疗对肝癌小鼠调节性 T 细胞的影响

目的：研究微波消融治疗荷肿瘤后小鼠的Treg和淋巴细胞亚群的变化,探讨微波消融治疗荷瘤小鼠后的机体免疫功能的变化.方法：建立H22荷瘤小鼠模型,分为荷瘤对照组和微波消融组.微波消融荷瘤小鼠肿瘤.流式细胞术检测脾脏中的CD4＋CD25＋T细胞、CD25＋FOXP3＋T细胞、CD4＋T细胞、CD8＋T细胞.结果：与荷瘤对照组相比,微波消融治疗后21天、28天组小鼠CD25＋FOXP3＋T细胞明显下降,差异有统计学意义（P＜0.05）,以术后28天下降更为明显（P＜0.01）.微波消融术后各组小鼠CD4＋/CD8＋比值明显增高（P＜0.05）.结论：微波消融治疗减低Tregs比例可能是热消融治疗提高机体抗肿瘤免疫作用的主要机制.微波消融治疗肿瘤后,Treg数量下降及功能降低,且CD4＋/CD8＋比值升高,提示了微波消融治疗肝癌可以改善机体的免疫状态.     

Increased expression of immunosuppressive molecules on intratumoral and circulating regulatory T cells in non-small-cell lung cancer patients

The expression patterns of immunosuppressive molecules on regulatory T (Treg) cells have not been elucidated in non-small-cell lung cancer (NSCLC) patients. In this study, a total of 88 patients including 53 patients with NSCLC, 17 patients with lung non-malignant diseases, and 18 healthy volunteers were enrolled. Increased number of total CD4⁺CD25⁺FoxP3⁺ Treg cells and elevated expressions on the surface of several inhibitory molecules including CTLA-4, LAG-3 and PD-1 have been observed in the peripheral blood of NSCLC patients. We found that intratumoral Treg cells from NSCLC patients express the highest levels of co-inhibitory molecules compared to Treg cells isolated from tumor adjacent tissues or from peripheral blood of cancer patients, which is in consistent with the enhanced immunosuppressive function of these co-inhibitory molecules. Moreover, the number of Treg cells and their functional surface molecules increased during the progression of lung cancer. Elevated plasma levels of TGF-β and IL-10 in NSCLC patients were also observed in NSCLC patients compared to that in healthy volunteers. Our findings further support the role of Treg cells in the tumor microenvironments in NSCLC patients.     

Mature dendritic cells enriched in regulatory molecules may control regulatory T cells and the prognosis of head and neck cancer

We previously reported that regulatory T (Treg) cells expressing CTLA-4 on the cell surface are abundant in head and neck squamous cell carcinoma (HNSCC). The role of expanded Treg cells in the tumor microenvironment of HNSCC remains unclear. In this study, we reveal that the tumor microenvironment of HNSCC is characterized by the high expression of genes related to Treg cells, dendritic cells (DCs), and interleukin (IL)-17-related molecules. Increased expression of IL17A, IL17F, or IL23A contributes to a favorable prognosis of HNSCC. In the tumor microenvironment of HNSCC, IL23A and IL12B are expressed in mature dendritic cells enriched in regulatory molecules (mregDCs). The mregDCs in HNSCC are a migratory and mature phenotype; their signature genes strongly correlate with Treg signature genes in HNSCC. We also observed that IL17A was highly expressed in Th17 cells and exhausted CD8⁺ T cells in HNSCC. These data suggest that mregDCs in HNSCC may contribute to the prognosis by balancing Treg cells and effector T cells that produce IL-17. Targeting mregDCs may be a novel strategy for developing new immune therapies against HNSCC.     

Increased expression of MCM4 is associated with poor prognosis in patients with hepatocellular carcinoma

BackgroundThe minichromosome maintenance (MCM) protein complex is important for DNA replication. Moreover, the expression of specific MCM complex components has been associated with the survival of hepatocellular carcinoma (HCC) patients. However, the expression and functional roles of minichromosome maintenance complex component 4 (MCM4) in HCC development and progression have not yet been explored. We analyzed the expression and clinical significance of MCM4, including its association with liver cancer patient survival.MethodsOncomine, UALCAN, and HCCDB (a database of HCC expression atlas) were used to characterize the expression of MCM4 in tumor and normal tissues. The expression of MCM4 at the protein level was confirmed based on immunohistochemistry (IHC) data obtained from the Human Protein Atlas (HPA) database. The level of MCM4 was measured in tumor and adjacent normal tissues by RT-qPCR, western blot and IHC staining. The copy number alterations (CNAs) and mutations in MCM4 were analyzed by cBioPortal, whereas the co-expression genes of MCM4 in HCC were obtained from Oncomine, and used for gene ontology and pathway analysis via the NetworkAnalyst 3.0 tool, to explore the predictive signaling pathway in HCC.ResultsThe levels of MCM4 messenger (m)RNA and protein were found to be significantly higher in liver cancer tissues than in normal liver tissues. Kaplan-Meier analysis showed that the upregulation of MCM4 was significantly negatively correlated with the survival of HCC patients.ConclusionsOur data suggest that MCM4 may be used as a potential prognostic marker and therapeutic target for HCC.     

Increased RBM12 expression predicts poor prognosis in hepatocellular carcinoma based on bioinformatics

BackgroundLiver cancer is one of the major causes of cancer death worldwide, incurring high mortality and a significant financial burden on the healthcare system. Abnormal RNA-binding proteins (RBPs) have been found to be associated with carcinogenesis in liver cancer. Among these, RNA-binding motif protein 12 (RBM12) is located in the exon junction complex (EJC). The goal of this study was to determine what role RBM12 plays in hepatocellular carcinoma (HCC) from a biological perspective.MethodsThe Tumor IMmune Estimation Resource (TIMER) and the Human Protein Atlas database were used to examine the expression level of RBM12, with the UALCAN and Gene Expression Profiling Interactive Analysis (GEPIA) databases used to investigate the relationship between RBM12 and other noteworthy clinical features. RBM12 expression in cells and tissue samples was detected using quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis. The functional network of RBM12 in HCC was studied using LinkedOmics and gene set enrichment analysis (GSEA), while the effects of hypomethylation on the expression of RBM12 in HCC was investigated using methylation databases. Finally, we used TIMER and CIBERSORT to investigate the relationship between immune cell infiltration and RBM12 in HCC.ResultsRBM12 is highly elevated in HCC tissues and cells, and it can be used to predict the prognosis of patients with HCC. Analysis with LinkedOmics and GSEA revealed RBM12 to be closely linked with tumor progression. Furthermore, hypomethylation was linked to an increase in RBM12 expression in HCC, while RBM12 was associated with immune cell infiltration.ConclusionsThis study shows that an elevated level of RBM12 in HCC indicates a poor patient prognosis. Furthermore, according to LinkedOmics and GSEA analyses, RBM12 was implicated in the most important hallmark pathways. Our findings suggest that RBM12 overexpression is caused by hypomethylation and that RBM12 plays a key role in liver cancer tumor immunity.     

Clinical significance of regulatory T cells and CD8+ effector populations in patients with human endometrial carcinoma

BACKGROUND:

A study was carried out to determine the functional attributes of CD4⁺ CD25⁺ regulatory T cells in cancer progression by suppressing antitumor immunity.

METHODS:

Triple‐color flow cytometry was used to study the phenotype expression of CD4⁺ CD25⁺ regulatory T cells and CD8⁺ T cells in the peripheral blood lymphocytes (PBLs) and tumor‐infiltrating lymphocytes (TILs) of 57 cases of stage I to IV endometrial carcinoma. The expression of T cell subsets was correlated with clinical prognostic parameters.

RESULTS:

The prevalence of CD4⁺ CD25⁺ T cells was significantly higher in the TILs than PBLs. The expression of CD4⁺ CD25⁺ regulatory T cells in cancer milieu correlated with the tumor grade, stage, and myometrium invasion. The expression of FOXP3 and GITR in CD4⁺ CD25⁺ regulatory T cells was lower in PBLs than TILs. Most tumor‐infiltrating CD8⁺ T cells were CD28^? CD45RA^? CD45RO⁺ CCR7^?, suggesting good terminal differentiation. Most of them had an activated role with CD69⁺ CD103⁺ CD152⁺. Functionally, both granzyme B and perforin were scarcely expressed in peripheral regulatory T cells but were highly expressed in peripheral regulatory T cells in the tumor microenvironment. In contrast, CD8⁺ cytotoxic T cells derived from PBLs expressed both granzyme B and perforin, and at significantly higher levels than in TILs. Further functional assays demonstrated that Th1 cytokines and cytotoxic molecules can be synchronously up‐regulated in CD8⁺ cytotoxic T cells.

CONCLUSIONS:

Regulatory T cells in the tumor microenvironment may abrogate CD8⁺ T cell cytotoxicity in a granzyme B‐ and perforin‐dependent conduit. Decreases in both Th1 cytokines and cytotoxic enzymes are relevant for regulatory T cell‐mediated restraint of tumor clearance in vivo. Of clinical significance, the expression of regulatory T cells in TILs may mediate T cell immune repression within cancer milieu and thus greatly correlate with cancer progression. Cancer 2010. © 2010 American Cancer Society.     

Prognostic value of tumor-infiltrating FOXP3 regulatory T cells in patients with hepatocellular carcinoma

Aims

CD4⁺ CD25⁺ forkhead box P3 (FOXP3)⁺ T_reg accumulate in malignant tumors and negatively regulate anti-tumor immunity. To determine the prognostic value of tumor-infiltrating regulatory T cells (T_reg), we conducted a retrospective study on 164 patients with hepatocellular carcinoma (HCC) who underwent curative hepatic resection.

Methods

We investigated the number of tumor-infiltrating FOXP3⁺ T_reg in formalin-fixed HCC specimens. The number of FOXP3⁺ T_reg for each case was calculated as the total number of positive cells per 10 high-power fields (HPF) on light microscopy. Long-term survival rate after resection according to the number of FOXP3⁺ T_reg was accessed by univariate and multivariate analyses.

Results

The mean and median numbers of tumor-infiltrating T_reg were 29.0 and 14 per 10 HPF for FOXP3⁺ T_reg. The number of FOXP3⁺ T_reg was positively correlated with preoperative serum alpha-fetoprotein levels. The disease-free survival rate was significantly lower in patients with high T_reg counts (≥14, n = 84) than in those with low T_reg counts (<14, n = 80) (13.6% vs. 25.7% at 5 years; P = 0.02). By multivariate analysis, the high T_reg counts, presence of portal vein invasion, and elevation of preoperative aspartate aminotransferase level were independent predictive factors of tumor recurrence.

Conclusions

The high number of tumor-infiltrating T_reg is an independent predictive factor of tumor recurrence after hepatic resection for HCC.     

肝细胞癌预后相关细胞分子生物标志物研究进展

肝细胞癌（HCC）的发生发展过程是一个多种基因和细胞、分子以及多条信号通路参与的复杂网络机制。不同水平的生物分子标志物作用与机制也各不相同,但目前仍缺乏对 HCC 患者预后进行评价的有效分子标志物。研究表明,在 HCC 的基因表达与调控过程以及细胞周期调节及肿瘤干细胞增殖与分化过程中均有相应的分子标志物参与。其中,p53基因及其相关分子、非编码转录 RNA（微小RNA、长链非编码 RNA ）、细胞周期调节因子和肝癌干细胞表面相关分子与 HCC 的预后密切相关。     

Downregulation of RFX1 predicts poor prognosis of patients with small hepatocellular carcinoma

Objective

Regulatory factor X1 (RFX1) deletion has been reported to be correlated with poor prognosis of some types of cancer. The present study aimed to investigate the prognostic value of RFX1 in HCC, especially in small hepatocellular carcinoma.

Endothelium-coated tumor clusters are associated with poor prognosis and micrometastasis of hepatocellular carcinoma after resection

BACKGROUND:

Distinct morphologic features of microvascular endothelium exist in tumor tissues. The objective of this study was to investigate the prognostic value of endothelium‐coated tumor clusters (ECTCs) in hepatocellular carcinoma (HCC).

METHODS:

ECTCs were evaluated by immunohistochemical staining for cluster of differentiation 34 (CD34) (a cell surface glycoprotein which is expressed specifically on tumor microvascular endothelium in HCC) in 239 specimens from patients with primary HCC. Overall survival (OS) and time to recurrence (TTR) were determined using Kaplan‐Meier analysis and a Cox proportional hazards regression model. Levels of terminal deoxynucleotide transferase‐mediated deoxyuridine triphosphate nick‐end labeling (TUNEL) staining, and Ki‐67 expression, and E‐cadherin expression were assessed to determine tumor apoptosis, proliferation, and invasiveness, respectively.

RESULTS:

The presence of ECTCs was associated with a poor prognosis in all patients and in patient subgroups stratified by tumor size, TNM classification, and Barcelona Clinic Liver Cancer stage and tumor invasiveness. In a multivariate Cox proportional hazards analysis, the presence of ECTCs emerged as an independent prognostic indicator of both poor OS (P = .001; hazard ratio, 1.949) and shorter TTR (P < .001; hazard ratio, 2.085). Furthermore, the presence of ECTCs was associated with micrometastatic endothelium‐coated emboli (P < .001; chi‐square test) and early relapse after resection (P < .001; chi‐square test). In addition, patients who had endothelium‐coated emboli, in which tumor cells displayed high proliferation and low apoptosis, had poor OS and shorter TTR.

CONCLUSIONS:

The current results suggested that the presence of ECTCs was an efficient, simple, and convenient predictor of a poor prognosis in patients with HCC that potentially may serve as a novel target for the prevention and treatment of HCC metastasis. Cancer 2011;. © 2011 American Cancer Society.     

Ack1 overexpression promotes metastasis and indicates poor prognosis of hepatocellular carcinoma

Despite the substantial data supporting the oncogenic role of Ack1, the predictive value and biologic role of Ack1 in hepatocellular carcinoma (HCC) metastasis remains unknown. In this study, both correlations of Ack1 expression with prognosis of HCC, and the role of Ack1 in metastasis of HCC were investigated in vitro and in vivo. Our results showed that Ack1 was overexpressed in human HCC tissues and cell lines. High Ack1 expression was associated with HCC metastasis and determined as a significant and independent prognostic factor for HCC after liver resection. Ack1 promoted HCC invasion and metastasis in vitro and in vivo. Mechanistically, we confirmed that Ack1 enhanced invasion and metastasis of HCC via EMT by mediating AKT phosphorylation. In conclusion, our study shows Ack1 is a novel prognostic biomarker for HCC and promotes metastasis of HCC via EMT by activating AKT signaling.     

Sorafenib reduces the percentage of tumour infiltrating regulatory T cells in renal cell carcinoma patients

Tyrosine kinase inhibitors (TKIs) as sorafenib are known to reduce the number of immunosuppressive regulatory T cells (Tregs) in the peripheral blood and thereby shifting the immune balance to a more stimulating setting. The effect of sorafenib on intratumoural Tregs is unclear but important for future combinations of TKIs and immunotherapy. We, therefore, evaluated the accumulation of regulatory T cells (Tregs, defined as, CD4⁺FoxP3⁺CD25^highCD127^low‐cells) in blood, ascites, metastases and primary tumours of patients with renal cell carcinoma (RCC), and we explored the effect of neoadjuvant treatment with sorafenib 400 mg bid on intratumoural Tregs in 11 patients with RCC in comparison to 15 nontreated RCC patients. We found that immunosuppressive Tregs specifically accumulate in primary tumour, metastases and ascites of RCC‐patients. Tumour infiltrating Tregs were functional. Neoadjuvant sorafenib treatment significantly reduced the percentage of tumour‐infiltrating Tregs (mean 17.3% vs. 28.1%, p = 0.046). Diminished Treg accumulation at the tumour site adds to explain the clinical effectiveness of sorafenib treatment. This observation may have important implications for the use of sorafenib in combination with immunotherapy in patients with RCC, since the depletion of Tregs has been associated with enhanced responses on vaccine mediated immunotherapy.