Purpose: Our preclinical studies demonstrated the potential of chimeric antigen receptor (CAR)-glypican-3 (GPC3) T-cell therapy for hepatocellular carcinoma (HCC). We report herein the first published results of CAR-GPC3 T-cell therapy for HCC. Patients and Methods: In two prospective phase I studies, adult patients with advanced GPC3 þ HCC (Child-Pugh A) received autologous CAR-GPC3 T-cell therapy following cyclophosphamide-and fludarabine-induced lymphodepletion. The primary objective was to assess the treatment's safety. Adverse events were graded using the Common Terminology Criteria for Adverse Events (version 4.03). Tumor responses were evaluated using the RECIST (version 1.1). Results: A total of 13 patients received a median of 19.9 Â 10 8 CAR-GPC3 T cells by a data cutoff date of July 24, 2019. We observed pyrexia, decreased lymphocyte count, and cytokine release syndrome (CRS) in 13, 12, and nine patients, respectively. CRS (grade 1/2) was reversible in eight patients. One patient experienced grade 5 CRS. No patients had grade 3/4 neurotoxicity. The overall survival rates at 3 years, 1 year, and 6 months were 10.5%, 42.0%, and 50.3%, respectively, according to the Kaplan-Meier method. We confirmed two partial responses. One patient with sustained stable disease was alive after 44.2 months. CAR T-cell expansion tended to be positively associated with tumor response. Conclusions: This report demonstrated the initial safety profile of CAR-GPC3 T-cell therapy. We observed early signs of antitumor activity of CAR-GPC3 T cells in patients with advanced HCC.

Despite success in hematologic malignancies, the treatment landscape of chimeric antigen receptor (CAR) T cell therapy for solid tumors remains limited. Claudin18.2 (CLDN18.2)-redirected CAR T cells showed promising efficacy against gastric cancer (GC) in a preclinical study. Here we report the interim analysis results of an ongoing, open-label, single-arm, phase 1 clinical trial of CLDN18.2-targeted CAR T cells (CT041) in patients with previously treated, CLDN18.2-positive digestive system cancers (NCT03874897). The primary objective was safety after CT041 infusion; secondary objectives included CT041 efficacy, pharmacokinetics and immunogenicity. We treated 37 patients with one of three CT041 doses: 2.5 × 108, 3.75 × 108 or 5.0 × 108 cells. All patients experienced a grade 3 or higher hematologic toxicity. Grade 1 or 2 cytokine release syndrome (CRS) occurred in 94.6% of patients. No grade 3 or higher CRS or neurotoxicities, treatment-related deaths or dose-limiting toxicities were reported. The overall response rate (ORR) and disease control rate (DCR) reached 48.6% and 73.0%, respectively. The 6-month duration of response rate was 44.8%. In patients with GC, the ORR and DCR reached 57.1% and 75.0%, respectively, and the 6-month overall survival rate was 81.2%. These initial results suggest that CT041 has promising efficacy with an acceptable safety profile in patients with heavily pretreated, CLDN18.2-positive digestive system cancers, particularly in those with GC.

CLDN18.2-specific CAR T cells could be a promising treatment strategy for gastric cancer and potentially other CLDN18.2-positive tumors.

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Adoptive immunotherapy based on chimeric antigen receptor–modified T (CAR-T) cells has been demonstrated as one of the most promising therapeutic strategies in the treatment of malignancies. However, CAR-T cell therapy has shown limited efficacy for the treatment of solid tumors. This is, in part, because of tumor heterogeneity and a hostile tumor microenvironment, which could suppress adoptively transferred T cell activity. In this study, we, respectively, engineered human- or murine-derived–armored glypican-3 (GPC3)–specific CAR-T cells capable of inducibly expressing IL-12 (GPC3-28Z-NFAT-IL-12) T cells. The results showed that GPC3-28Z-NFAT-IL-12 T cells could lyse GPC3+ tumor cells specifically and increase cytokine secretion compared with GPC3-28Z T cells in vitro. In vivo, GPC3-28Z-NFAT-IL-12 T cells augmented the antitumor effect when encountering GPC3+ large tumor burdens, which could be attributed to IL-12 increasing IFN-γ production, favoring T cells infiltration and persistence. Furthermore, in immunocompetent hosts, low doses of GPC3-m28Z-mNFAT-mIL-12 T cells exerted superior antitumor efficacy without prior conditioning in comparison with GPC3-m28Z T cells. Also, mIL-12 secretion decreased regulatory T cell infiltration in established tumors. In conclusion, these findings demonstrated that the inducible expression of IL-12 could boost CAR-T function with less potential side effects, both in immunodeficient and immunocompetent hosts. The inducibly expressed IL-12–armored GPC3–CAR-T cells could broaden the application of CAR-T–based immunotherapy to patients intolerant of lymphodepletion chemotherapy and might provide an alternative therapeutic strategy for patients with GPC3+ cancers.

Adoptive immunotherapy leveraging chimeric antigen receptor-modified T (CAR-T) cells holds great promise for the treatment of cancer. However, tumor-associated antigens often have low expression levels in normal tissues, which can cause on-target, off-tumor toxicity. Recently, we reported that GPC3-targeted CAR-T cells could eradicate hepatocellular carcinoma (HCC) xenografts in mice. However, it remains unknown whether on-target, off-tumor toxicity can occur. Therefore, we proposed that dual-targeted CAR-T cells co-expressing glypican-3 (GPC3) and asialoglycoprotein receptor 1 (ASGR1) (a liver tissue-specific protein)-targeted CARs featuring CD3ζ and 28BB (containing both CD28 and 4-1BB signaling domains), respectively, may have reduced on-target, off-tumor toxicity. Our results demonstrated that dual-targeted CAR-T cells caused no cytotoxicity to ASGR1GPC3 tumor cells, but they exhibited a similar cytotoxicity against GPC3ASGR1 and GPC3ASGR1 HCC cells in vitro. We found that dual-targeted CAR-T cells showed significantly higher cytokine secretion, proliferation and antiapoptosis ability against tumor cells bearing both antigens than single-targeted CAR-T cells in vitro. Furthermore, the dual-targeted CAR-T cells displayed potent growth suppression activity on GPC3ASGR1 HCC tumor xenografts, while no obvious growth suppression was seen with single or double antigen-negative tumor xenografts. Additionally, the dual-targeted T cells exerted superior anticancer activity and persistence against single-targeted T cells in two GPC3ASGR1 HCC xenograft models. Together, T cells carrying two complementary CARs against GPC3 and ASGR1 may reduce the risk of on-target, off-tumor toxicity while maintaining relatively potent antitumor activities on GPC3ASGR1 HCC.

BackgroundEpidermal growth factor receptor (EGFR), a well-known oncogenic driver, contributes to the initiation and progression of a wide range of cancer types. Aberrant lipid metabolism including highly produced monounsaturated fatty acids (MUFA) is recognized as a hallmark of cancer. However, how EGFR regulates MUFA synthesis in cancer remains elusive. This is the focus of our study.MethodsThe interaction between EGFR and stearoyl-CoA desaturase-1 (SCD1) was detected byco-immunoprecipitation. SCD1 protein expression, stability and phosphorylation were tested by western blot. The synthesis of MUFA was determined by liquid chromatography-mass spectrometry. The growth of lung cancer was detected by CCK-8 assay, Annexin V/PI staining, colony formation assay and subcutaneous xenograft assay. The expression of activated EGFR, phosphorylated and total SCD1 was tested by immunohistochemistry in 90 non-small cell lung cancersamples. The clinical correlations were analyzed by Chi-square test, Kaplan-Meier survival curve analysis and Cox regression.ResultsEGFR binds to and phosphorylates SCD1 at Y55. Phosphorylation of Y55 is required for maintaining SCD1 protein stability and thus increases MUFA level to facilitate lung cancer growth. Moreover, EGFR-stimulated cancer growth depends on SCD1 activity. Evaluation of non-small cell lung cancersamples reveals a positive correlation among EGFR activation, SCD1 Y55 phosphorylation and SCD1 protein expression. Furthermore, phospho-SCD1 Y55 can serve as an independent prognostic factor for poor patient survival.ConclusionsOurstudy demonstrates that EGFR stabilizes SCD1 through Y55 phosphorylation, thereby up-regulating MUFA synthesis to promote lung cancer growth. Thus, we provide the first evidence that SCD1 can be subtly controlled by tyrosine phosphorylation and uncover a previously unknown direct linkage between oncogenic receptor tyrosine kinase and lipid metabolism in lung cancer. We also propose SCD1 Y55 phosphorylation as a potential diagnostic marker for lung cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/s12943-017-0704-x) contains supplementary material, which is available to authorized users.

2509 Background: As a promising approach for some cancers, chimeric antigen receptor T cell therapy has limited success in solid tumors. Claudin18.2 (CLDN 18.2) is a stomach-specific isoform of Claudin-18, and highly expressed in gastric and pancreatic adenocarcinoma, the advanced form of both of which have urgent unmet medical needs. We previously developed and demonstrated ability of CLDN 18.2-specific CAR (CAR-CLDN18.2) T cells to eradicate CLDN 18.2-positive gastric cancer xenografts without obvious on-target off-tumor toxicity (Huang J. JNCI 2018). Methods: In this single-arm, open-label, first-in-human phase I pilot study (NCT03159819) to investigate the safety and explore the efficacy of the autologous CAR-CLDN18.2 T cells, patients with confirmed CLDN 18.2 positive advanced gastric or pancreatic adenocarcinoma aged 18 to 70 years received 1 or more cycles of CAR-CLDN18.2 T cell infusion(s) after lymphodepletion pretreatment (fludarabine and cyclophosphamide, with or without nab-paclitaxel) until disease progression or presence of intolerable toxicity. Adverse Event (AE) grade categorization is according to CTCAE 4.0, and tumor response was assessed per RECIST 1.1. Results: As of November 30th, 2018, 12 subjects with metastatic adenocarcinoma (7 gastric and 5 pancreatic) were treated with 1–5 cycles (total of 0.5 - 55 X 108) of CAR-positive T cells infusions. There were no serious adverse events, treatment-related death or severe neurotoxicity occurred in the study. No grade 4 AEs except for decreased lymphocytes, neutrophils and white blood cells. All cytokine release syndromes observed were grade 1 or 2. Among the 11 evaluable subjects, 1 achieved a complete response (gastric adenocarcinoma), 3 had partial responses (2 gastric adenocarcinomas and 1 pancreatic adenocarcinoma), 5 had stable disease and 2 had progression of disease. The total objective response rate was 33.3%, with median PFS of 130 days estimated using Kaplan-Meier method [95% CI (38, 230)]. Conclusions: This clinical study indicated that CAR-CLDN18.2 T cell therapy were safe and well tolerated and may have promising therapeutic efficacy in patients with advanced gastric and pancreatic adenocarcinoma. Clinical trial information: NCT03159819.