Targeted delivery of a PD-1-blocking scFv by CD133-specific CAR-T cells using nonviral Sleeping Beauty transposition shows enhanced antitumour efficacy for advanced hepatocellular carcinoma.

BACKGROUND: CD133 is considered a marker for cancer stem cells (CSCs) in several types of tumours, including hepatocellular carcinoma (HCC). Chimeric antigen receptor-specific T (CAR-T) cells targeting CD133-positive CSCs have emerged as a tool for the clinical treatment of HCC, but immunogenicity, the high cost of clinical-grade recombinant viral vectors and potential insertional mutagenesis limit their clinical application. METHODS: CD133-specific CAR-T cells secreting PD-1 blocking scFv (CD133 CAR-T and PD-1 s cells) were constructed using a sleeping beauty transposon system from minicircle technology, and the antitumour efficacy of CD133 CAR-T and PD-1 s cells was analysed in vitro and in vivo. RESULTS: A univariate analysis showed that CD133 expression in male patients at the late stage (II and III) was significantly associated with worse progression-free survival (PFS) (P = 0.0057) and overall survival (OS) (P = 0.015), and a multivariate analysis showed a trend toward worse OS (P = 0.041). Male patients with advanced HCC exhibited an approximately 20-fold higher PD-L1 combined positive score (CPS) compared with those with HCC at an early stage. We successfully generated CD133 CAR-T and PD-1 s cells that could secrete PD-1 blocking scFv based on a sleeping beauty system involving minicircle vectors. CD133 CAR-T and PD-1 s cells exhibited significant antitumour activity against HCC in vitro and in xenograft mouse models. Thus, CD133 CAR-T and PD-1 s cells may be a therapeutically tractable strategy for targeting CD133-positive CSCs in male patients with advanced HCC. CONCLUSIONS: Our study provides a nonviral strategy for constructing CAR-T cells that could also secrete checkpoint blockade inhibitors based on a Sleeping Beauty system from minicircle vectors and revealed a potential benefit of this strategy for male patients with advanced HCC and high CD133 expression (median immunohistochemistry score > 2.284).

Cancer-Associated Fibroblast-Mediated Cellular Crosstalk Supports Hepatocellular Carcinoma Progression.

BACKGROUND AND AIMS: Cancer-associated fibroblasts (CAFs) are key players in multicellular, stromal-dependent alterations leading to HCC pathogenesis. However, the intricate crosstalk between CAFs and other components in the tumor microenvironment (TME) remains unclear. This study aimed to investigate the cellular crosstalk among CAFs, tumor cells, and tumor-associated neutrophils (TANs) during different stages of HCC pathogenesis. APPROACH AND RESULTS: In the HCC-TME, CAF-derived cardiotrophin-like cytokine factor 1 (CLCF1) increased chemokine (C-X-C motif) ligand 6 (CXCL6) and TGF-ß secretion in tumor cells, which subsequently promoted tumor cell stemness in an autocrine manner and TAN infiltration and polarization in a paracrine manner. Moreover, CXCL6 and TGF-ß secreted by HCC cells activated extracellular signal-regulated kinase (ERK) 1/2 signaling of CAFs to produce more CLCF1, thus forming a positive feedback loop to accelerate HCC progression. Inhibition of ERK1/2 or CLCF1/ciliary neurotrophic factor receptor signaling efficiently impaired CLCF1-mediated crosstalk among CAFs, tumor cells, and TANs both in vitro and in vivo. In clinical samples, up-regulation of the CLCF1-CXCL6/TGF-ß axis exhibited a marked correlation with increased cancer stem cells, "N2"-polarized TANs, tumor stage, and poor prognosis. CONCLUSIONS: This study reveals a cytokine-mediated cellular crosstalk and clinical network involving the CLCF1-CXCL6/TGF-ß axis, which regulates the positive feedback loop among CAFs, tumor stemness, and TANs, HCC progression, and patient prognosis. These results may support the CLCF1 cascade as a potential prognostic biomarker and suggest that selective blockade of CLCF1/ciliary neurotrophic factor receptor or ERK1/2 signaling could provide an effective therapeutic target for patients with HCC.

Chimeric antigen receptor-modified T-cell therapy for platelet-derived growth factor receptor α-positive rhabdomyosarcoma.

BACKGROUND: New immunotherapeutic approaches are urgently needed for metastatic rhabdomyosarcoma, which is associated with poor survival and unsatisfactory treatment outcomes. Platelet-derived growth factor receptor α (PDGFRA) plays an essential role in the onset and development of rhabdomyosarcoma and is a new potential therapeutic target for rhabdomyosarcoma. The objective of this study was to generate humanized PDGFRA single-chain variable fragment-based chimeric antigen receptor (CAR)-modified T cells (CAR-T cells) against PDGFRA-positive rhabdomyosarcoma. METHODS: PDGFRA antigen expression was evaluated in specimens from patients with rhabdomyosarcoma. CAR-T cells containing a PDGFRA-specific single-chain variable fragment was developed in combination with a 4-1BB costimulatory domain and a CD3-ζ signaling domain. Specific cytotoxic effects of PDGFRA CAR-T cells, T-cell proliferation, and cytokine secretion were investigated in vitro and in vivo. RESULTS: PDGFRA CAR-T cells produced large amounts of immune-promoting cytokines, including interleukin 2, tumor necrosis factor α, and interferon γ, and exhibited efficient cytotoxic activity toward human PDGFRA-overexpressing rhabdomyosarcoma cells in vitro. In a subcutaneous xenograft model, CAR-T cells were more effective against PDGFRA-overexpressing rhabdomyosarcoma than against rhabdomyosarcoma with low PDGFRA expression in terms of tumor regression and patient survival. Expanded CAR-T cells also were detected in peripheral blood. CONCLUSIONS: The current study demonstrates for the first time that the PDGFRA antigen is a promising target for CAR-T-cell therapy in rhabdomyosarcoma and likely in a wide spectrum of other PDGFRA-expressing cancers.

Galectin-3 favours tumour metastasis via the activation of ß-catenin signalling in hepatocellular carcinoma.

BACKGROUND: High probability of metastasis limited the long-term survival of patients with hepatocellular carcinoma (HCC). Our previous study revealed that Galectin-3 was closely associated with poor prognosis in HCC patients. METHODS: The effects of Galectin-3 on tumour metastasis were investigated in vitro and in vivo, and the underlying biological and molecular mechanisms involved in this process were evaluated. RESULTS: Galectin-3 showed a close correlation with vascular invasion and poor survival in a large-scale study in HCC patients from multiple sets. Galectin-3 was significantly involved in diverse metastasis-related processes in HCC cells, such as angiogenesis and epithelial-to-mesenchymal transition (EMT). Mechanistically, Galectin-3 activated the PI3K-Akt-GSK-3ß-ß-catenin signalling cascade; the ß-catenin/TCF4 transcriptional complex directly targeted IGFBP3 and vimentin to regulate angiogenesis and EMT, respectively. In animal models, Galectin-3 enhanced the tumorigenesis and metastasis of HCC cells via ß-catenin signalling. Moreover, molecular deletion of Galectin-3-ß-catenin signalling synergistically improved the antitumour effect of sorafenib. CONCLUSIONS: The Galectin-3-ß-catenin-IGFBP3/vimentin signalling cascade was determined as a central mechanism controlling HCC metastasis, providing possible biomarkers for predicating vascular metastasis and sorafenib resistance, as well as potential therapeutic targets for the treatment of HCC patients.

CIK cell cytotoxicity is a predictive biomarker for CIK cell immunotherapy in postoperative patients with hepatocellular carcinoma.

Adjuvant cytokine-induced killer (CIK) cell immunotherapy has shown potential in improving the prognosis of hepatocellular carcinoma (HCC) patients after curative resection. However, whether an individual could obtain survival benefit from CIK cell treatment remains unknown. In the present study, we focused on the characteristics of CIK cells and aimed to identify the best predictive biomarker for adjuvant CIK cell treatment in patients with HCC after surgery. This study included 48 patients with HCC treated with postoperative adjuvant CIK cell immunotherapy. The phenotype activity and cytotoxic activity of CIK cells were determined by flow cytometry and xCELLigence™ Real-Time Cell Analysis (RTCA) system, respectively. Correlation analysis revealed that the cytotoxic activity of CIK cells was significantly negative correlated with the percentage of CD3+ CD4+ cell subsets, but significantly positive correlated with CD3-CD56+ and CD3+ CD56+ cell subsets. Survival analysis showed that there were no significant associations between patients' prognosis and the phenotype of CIK cells. By contrast, there was statistically significant improvement in recurrence-free survival (RFS) and overall survival (OS) for patients with high cytotoxic activity of CIK cells as compared with those with low cytotoxic activity of CIK cells. Univariate and multivariate analyses indicated that CIK cell cytotoxicity was an independent prognostic factor for RFS and OS. In conclusion, a high cytotoxic activity of CIK cells can serve as a valuable biomarker for adjuvant CIK cell immunotherapy of HCC patients after surgery.

SKA1 overexpression is associated with poor prognosis in hepatocellular carcinoma.

BACKGROUND: SKA1, an important mitosis protein, has been indicated in the initiation and progression of several malignancies. However, its clinical significance in hepatocellular carcinoma (HCC) remain to be elucidated. METHODS: mRNA expression of SKA1 was examined in 126 HCC and paired non-neoplastic tissues using real-time PCR and validated in The Cancer Genome Atlas (TCGA) database. SKA1 protein expression was detected using immunohistochemistry in the 126 HCC tissues and its associations with clinicopathological parameters and prognosis were analyzed. Hierarchical cluster analysis and gene set enrichment analysis (GSEA) were performed in selected Gene Expression Omnibus data sets. RESULTS: SKA1 mRNA expression was significantly elevated in HCC tissues from both local hospital and TCGA database. Immunohistochemistry revealed that increased SKA1 expression was present in 65 of the 126 cases and was significantly associated with higher serum alpha-fetoprotein concentration, larger tumor size and higher TNM stage. Patients with positive SKA1 expression showed significantly worse overall and relapse-free survival. Multivariate Cox regression analysis revealed that SKA1 was an independent predictor of patient prognosis. Gene expression profiling analysis of public data showed that high-SKA1 expression HCC tissues had similar gene expression profiles with fetal liver tissues. Moreover, GSEA showed that genes up-regulated in high SKA1 HCC subgroup were significantly enriched in cell cycle pathway, while genes down-regulated were significantly enriched in apoptosis pathway. CONCLUSIONS: Our findings indicate that the oncofetal gene SKA1 might be involved in the progression of the HCC and could serve as a prognostic marker for HCC.

Dendritic-cell-based immunotherapy evokes potent anti-tumor immune responses in CD105+ human renal cancer stem cells.

Cancer stem cells (CSCs) are responsible for tumor initiation, progression, and resistance to therapeutic agents; they are usually less sensitive to conventional cancer therapies, and could cause tumor relapse. An ideal therapeutic strategy would therefore be to selectively target and destroy CSCs, thereby preventing tumor relapse. The aim of the present study was to evaluate the effectiveness of dendritic cells (DCs) pulsed with antigen derived from CD105+ human renal cell carcinoma (RCC) CSCs against renal cancer cells in vitro and in vivo. We identified "stem-like" characteristics of CD105+ cells in two human RCC cell lines: A498 and SK-RC-39. Loading with cell lysates did not change the characteristics of the DCs. However, DCs loaded with lysates derived from CD105+ CSCs induced more functionally specific active T cells and specific antibodies against CSCs, and clearly depressed the tumor growth in mice. Our results could form the basis for a novel strategy to improve the efficacy of DC-based immunotherapy for human RCC.

Expression and prognostic role of ubiquitination factor E4B in primary hepatocellular carcinoma.

Ubiquitination factor E4B (UBE4B) has been speculated to have contradictory functions upon tumorigenesis as an oncogene or tumor suppressor in different types of cancers. We investigated the expression and prognostic role of UBE4B in primary hepatocellular carcinoma (HCC) using cell lines and 149 archived HCC samples. Correlation between the functions of UBE4B in HCC was also explored. We used human HCC cell lines (HepG2, Hep3B, SK-Hep1, Huh7, SMMC-7721, BEL-7402) and a normal hepatocyte cell line (LO2) along with HCC samples from patients who had undergone resection for HCC previously at our hospital. A battery of methods (real-time quantitative polymerase chain reaction; Western blotting; immunohistochjemical analyses; cell proliferation and colony formation assays; cell migration and cell invasion assays) were employed to assess various aspects of UBE4B.We found that UBE4B expression was upregulated aberrantly at mRNA and protein levels in human primary HCC tissues. Amplified expression of UBE4B was highly correlated with poor outcome. Silencing of UBE4B expression by siRNA inhibited the proliferation, colony formation, migration and invasion of HCC cells in vitro, and resulted in significant apoptosis that was associated with downregulation of expression of Bcl-2 and upregulation of expression of total p53, p-p53, Bax and Cleaved-Caspase3 in HCC cells. Our findings suggested that UBE4B might have an oncogenic role in human primary HCC, and that it could be used as a prognostic marker (as well as a potential molecular target) for the treatment of HCC.

Annexin A3 as a potential target for immunotherapy of liver cancer stem-like cells.

Cancer stem-like cells/cancer-initiating cells (CSCs/CICs) are considered to represent a small population of cancer cells that is resistant to conventional cancer treatments and responsible for tumor recurrence and metastasis. The aim of this study was to establish CSC/CIC-targeting immunotherapy. In this study, we found that Annexin A3 (ANXA3) was preferentially expressed in CSCs/CICs derived from hepatocellular carcinoma (HCC) cells compared to non-CSCs/CICs. In HCC samples, high levels of ANXA3 correlated with expansion of CD133(+) tumor cells representing CSCs/CICs in HCC; the combination of high levels of ANXA3 and CD133 was associated with progression of HCC. Overexpression of ANXA3 increased the proportion of CD133(+) cells, enhancing their tumorigenicity. On the contrary, knockdown of ANXA3 decreased CD133(+) cells and inhibited tumorigenicity. The mechanistic study revealed that ANXA3-mediated maintenance of HCC CSCs/CICs activity was likely involved with the HIF1A/Notch pathway. Using ANXA3 as a target, ANXA3-transfected dendritic cells could induce more functionally active T cells and these effector T cells could superiorly kill CD133(+) HCC CSCs/CICs in vitro and in vivo. Taken together, our findings suggest that ANXA3 plays a role in HCC CSC/CIC maintenance, and that ANXA3 may represent a potential CSC/CIC-specific therapeutic target for improving the treatment of HCC.

Annexin A3 promotes tumorigenesis and resistance to chemotherapy in hepatocellular carcinoma.

Annexin A3 (ANXA3) has been found to play important roles in cancer progression, metastasis, and drug resistance; however, its role in hepatocellular carcinoma (HCC) remains unknown. In this study, we investigated the expression level, clinical significance and biologic function of ANXA3 in HCC. Real-time quantitative reverse transcriptase-polymerase chain reaction, western blotting and immunohistochemical staining were used to examine ANXA3 expression levels in HCC tumor tissue, and its correlation with the clinicopathological features and prognosis of HCC patients was analyzed. The biological functions of ANXA3 in cell proliferation, migration, invasion, and resistance to chemotherapy were also investigated. ANXA3 expression was significantly increased in HCC tissues as compared with adjacent non-tumorous tissues. Elevated ANXA3 expression was associated with tumor size, number of lesions, tumor stage, and poor prognosis. In hepatoma cell lines, exogenous ANXA3 transduction promoted the tumorigenic activity and metastatic potential of tumor cells. Small interfering RNA silencing of ANXA3 inhibited these processes. In addition, in vitro and in vivo experiments revealed that ANXA3 overexpression enhanced resistance to chemotherapy. Taken together, our findings reveal that ANXA3 might play an important role in HCC progression and chemoresistance, and could serve as a novel prognostic marker and therapeutic target for HCC.