616 Poster The p53 status of tumor cells controlled hypoxic fractions and affected pr-350-induced radiosensitization in solid tumors

2002 ◽  
Vol 64 ◽  
pp. S190
Keyword(s):  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shao-Yuan Chen ◽  
Koichi Tsuneyama ◽  
Mao-Hsiung Yen ◽  
Jiunn-Tay Lee ◽  
Jiun-Liang Chen ◽  
...  

AbstractTumor cells have long been recognized as a relative contraindication to hyperbaric oxygen treatment (HBOT) since HBOT might enhance progressive cancer growth. However, in an oxygen deficit condition, tumor cells are more progressive and can be metastatic. HBOT increasing in oxygen partial pressure may benefit tumor suppression. In this study, we investigated the effects of HBOT on solid tumors, such as lung cancer. Non-small cell human lung carcinoma A549-cell-transferred severe combined immunodeficiency mice (SCID) mice were selected as an in vivo model to detect the potential mechanism of HBOT in lung tumors. HBOT not only improved tumor hypoxia but also suppressed tumor growth in murine xenograft tumor models. Platelet endothelial cell adhesion molecule (PECAM-1/CD31) was significantly increased after HBOT. Immunostaining of cleaved caspase-3 was demonstrated and apoptotic tumor cells with nuclear debris were aggregated starting on the 14th-day after HBOT. In vitro, HBOT suppressed the growth of A549 cells in a time-dependent manner and immediately downregulated the expression of p53 protein after HBOT in A549 cells. Furthermore, HBOT-reduced p53 protein could be rescued by a proteasome degradation inhibitor, but not an autophagy inhibitor in A549 cells. Our results demonstrated that HBOT improved tissue angiogenesis, tumor hypoxia and increased tumor apoptosis to lung cancer cells in murine xenograft tumor models, through modifying the tumor hypoxic microenvironment. HBOT will merit further cancer therapy as an adjuvant treatment for solid tumors, such as lung cancer.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A163-A163
Author(s):  
Yui Harada ◽  
Yoshikazu Yonemitsu

BackgroundCancer immunotherapy has been established as a new therapeutic category since the recent success of immune checkpoint inhibitors and a type of adoptive immunotherapy, namely chimeric antigen receptor-modified T cells (CAR-T). Although CAR-T demonstrated impressive clinical results, serious adverse effects (cytokine storm and on-target off-tumor toxicity) and undefined efficacy on solid tumors are important issues to be solved. We’ve developed a cutting-edge, simple, and feeder-free method to generate highly activated and expanded human NK cells from peripheral blood (US9404083, PCT/JP2019/012744, PCT/JP2020/012386), and have been conducting further investigation why our new type of NK cells, named as GAIA-102, are so effective to kill malignant cells.MethodsCryopreserved PBMCs purchased from vendors were mixed and processed by using LOVO and CliniMACS® Prodigy (automated/closed systems). CD3+ and CD34+ cells were depleted, and the cells were cultured with high concentration of hIL-2 and 5% UltraGRO® for 14 days in our original closed system. Then, we confirmed the expression of surface markers, CD107a mobilization and cell-mediated cytotoxicity against various tumor cells and normal cells with or without monoclonal antibody drugs in vitro and antitumor effects against peritoneal dissemination model using SKOV3 in vivo.ResultsImportantly, we’ve found that our GAIA-102 exhibited CD3-/CD56bright/CD57- immature phenotype that could kill various tumor cells efficiently from various origins, including Raji cells that was highly resistant to NK cell killing. More importantly, massive accumulation, retention, infiltration and sphere destruction by GAIA-102 were affected neither by myeloid-derived suppressor cells nor regulatory T-lymphocytes. GAIA-102 was also effective in vivo to murine model of peritoneal dissemination of human ovarian cancer; thus, these findings indicate that GAIA-102 has a potential to be an ‘upward compatible’ modality over CAR-T strategy, and would be a new and promising candidate for adoptive immunotherapy against solid tumors.ConclusionsWe now just started GMP/GCTP production of this new and powerful NK cells and first-in-human clinical trials in use of GAIA-102 will be initiated on 2021.Ethics ApprovalThe animal experiments were reviewed and approved by the Institutional Animal Care and Use Committee of Kyushu University (approval nos. A30-234-0 and A30-359-0).


2021 ◽  
Vol 9 (Suppl 1) ◽  
pp. A30.1-A30
Author(s):  
N Benhamouda ◽  
I Sam ◽  
N Epaillard ◽  
A Gey ◽  
A Saldmann ◽  
...  

BackgroundCD70, a costimulatory molecule on antigen presenting cells, is known to activate CD27-expressing T cells. CD27-CD70 interaction leads to the release of soluble CD27 (sCD27). However, persistent interaction of CD27 and CD70 such as in chronic infection may exhaust the T cell pool and promote apoptosis. Surprisingly, our analysis based on TCGA database show that clear cell renal cell carcinoma (ccRCC) expresses the highest levels of CD70 among all solid tumors. Despite the important clinical efficacy of immunotherapy by anti-PD-1 in RCC patients, the overall response to anti-PD1 remains modest. The relationship between the CD27-CD70 interaction in the RCC and the response to immunotherapy is still unclear.Materials and MethodsTo study the CD27 and CD70 expression in the tumor microenvironment (TME), FFPE tumor tissues from 25 RCC patients were analysed using multiplex in situ immunofluorescence. 10 fresh RCC tumor samples were collected to analyse the phenotype of CD27+ T cells by flow cytometry and 4 samples were proceeded for single-cell RNA-seq analysis. A cohort of metastatic RCC patients (n = 35) treated by anti-PD-1 were enrolled for the measurement of plasma sCD27 by ELISA and the survival analysis is also realized.ResultsIn the TME, we demonstrated that CD27+ T cells interact with CD70-expressing tumor cells. In fresh tumors from RCC patients, CD27+ T cells express higher levels of cleaved caspase 3 (a classical marker of apoptosis) than CD27- T cells. We confirmed the apoptotic signature (BAX, FASLG, BCL2L11, CYCS, FBXO32, LGALS1, PIK3R1, TERF1, TXNIP, CDKN2A) of CD27+ T cells by single-cell RNAseq analysis. CD27+T cells also had a tissue resident memory T cell phenotype with enriched gene expression of ITGAE, PRDM1, RBPJ and ZNF683. Moreover, CD27+T cells display an exhaustion phenotype with the expression of multiple inhibitory receptors gene signature (PDCD1, CTLA4, HAVCR2, LAG3, etc). Besides, intratumoral CD27-CD70 interaction significantly correlates with plasma sCD27 concentration in RCC (p = 0.0017). In metastatic RCC patients treated with anti-PD-1, higher levels of sCD27 predict poor overall survival (p = 0.037), while it did not correlate with inflammatory markers or clinical prognostic criteria.ConclusionsIn conclusion, we demonstrated that sCD27, a surrogate of T cell dysfunction in tumors likely induced by persistent interactions of CD27+T cells and CD70-expressing tumor cells, is a predictive biomarker of resistance to immunotherapy in mRCC. To our knowledge, this is the first report showing that a peripheral blood biomarker may reflect certain aspects of the tumor-host interaction in the tumor microenvironment. Given the frequent expression of CD70 and CD27 in solid tumors, our findings may be further extended to other types of tumors. CD70-CD27 interaction could thus be considered as a mechanism of tumor escape, but also a novel therapeutic target in cancers.Disclosure InformationN. Benhamouda: None. I. Sam: None. N. Epaillard: None. A. Gey: None. A. Saldmann: None. J. Pineau: None. M. Hasan: None. V. Verkarre: None. V. Libri: None. S. Mella: None. C. Granier: None. C. Broudin: None. P. Ravel: None. B. Jabla: None. N. Chaput: None. L. Albiges: None. Y. Vano: None. O. Adotevi: None. S. Oudard: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; SIRIC CARPEM, FONCER. E. Tartour: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; Fondation ARC, INCA PLBio, Labex Immuno-Oncology, SIRIC CARPEM, FONCER, IDEX université de Paris, Inserm Transfert.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A834-A834
Author(s):  
Xue Yao ◽  
Sandro Matosevic

BackgroundThe effectiveness of natural killer (NK) cell-based immunotherapy against solid tumors is limited by the lack of specific antigens and the immunosuppressive tumor microenvironment (TME). Glioblastoma multiforme (GBM) is one such heavily immunosuppressive tumor that has been particularly hard to target and remains without a viable treatment. The development of novel approaches to enhance the efficacy of NK cells against GBM is urgently needed. NK cell engagers (NKCE) have been developed to enhance the efficacy of NK cell therapy.MethodsTo improve the clinical efficacy of NK cell therapy, we are developing a new generation of multi-specific killer engagers, which consists of a neoantigen-targeting moiety, together with cytokine and chemokine-producing domains. Neoantigens are new antigens formed specifically in tumor cells due to genome mutations, making them highly specific tools to target tumor cells. Our engager has been designed to target Wilms' tumor-1 (WT-1), a highly specific antigen overexpressed in GBM among other solid tumors. This is done through the generation of an scFv specific targeting the complex of WT-1126-134/HLA-A*02:01 on the surface of GBM. On the NK cell side, the engager is designed to target the activating receptor NKp46. Incorporation of the cytokine IL-15 within the engager supports the maturation, persistence, and expansion of NK cells in vivo while favoring their proliferation and survival in the tumor microenvironment. Additionally, our data indicated that the chemokine CXCL10 plays an important role in the infiltration of NK cells into GBM, however, GBM tumors produce low levels of this chemokine. Incorporation of a CXCL10-producing function into our engager supports intratumoral NK cell trafficking by promoting, through their synthetic production, increased levels of CXCL10 locally in the tumor microenvironment.ResultsCollectively, this has resulted in a novel multifunctional NK cell engager, combining neoantigen-cytokine-chemokine elements fused to an activating domain-specific to NK cells, and we have investigated its ability to support and enhance NK cell-mediated cytotoxicity against solid tumors in vitro and in vivo against patient-derived GBM models. The multi-specific engager shows both high tumor specificity, as well as the ability to overcome NK cell dysfunction encountered in the GBM TME.ConclusionsWe hypothesize that taking advantage of our multi-functional engager, NK cells will exhibit superior ex vivo expansion, infiltration, and antitumor activity in the treatment of GBM and other solid tumors.


2021 ◽  
Author(s):  
Ashwini Sadanand Ranade ◽  
Joseph R Bertino ◽  
Longqin Hu

Abstract 5′-Methylthioadenosine (MTA) is a natural substrate of MTA phosphorylase (MTAP) and is converted to adenine via a salvage pathway for AMP production in normal healthy cells. The lack of MTAP expression in many solid tumors and hematologic malignancies compared to normal healthy cells has been explored in a potential therapeutic strategy to selectively target tumor cells using antimetabolites such as 5-fluorouracil (5-FU) and 6-thioguanine (6-TG) while protecting normal healthy cells with MTA. Herein, a series of carbamate prodrugs, namely the N-(alkyloxy)carbonyl-MTA derivatives 2a-f, was designed, synthesized, and evaluated as potential prodrugs of MTA. All carbamate prodrugs were stable in phosphate buffer, pH 7.4 at 37 °C. In the presence of mouse liver microsomes, the prodrugs were converted to MTA at varying rates with the hexyl and butyl carbamates 2a and 2b most readily activated (t1/2 of 1.2 and 9.4 h, respectively). The activation was shown to be mediated by carboxyesterases present in mouse liver microsomes.


2021 ◽  
Vol 12 ◽  
Author(s):  
Luis Felipe Olguín-Contreras ◽  
Anna N. Mendler ◽  
Grzegorz Popowicz ◽  
Bin Hu ◽  
Elfriede Noessner

Activation of co-stimulatory pathways in cytotoxic T lymphocytes expressing chimeric antigen receptors (CARs) have proven to boost effector activity, tumor rejection and long-term T cell persistence. When using antigen-specific T cell receptors (TCR) instead of CARs, the lack of co-stimulatory signals hampers robust antitumoral response, hence limiting clinical efficacy. In solid tumors, tumor stroma poses an additional hurdle through hindrance of infiltration and active inhibition. Our project aimed at generating chimeric co-stimulatory switch proteins (CSP) consisting of intracellular co-stimulatory domains (ICD) fused to extracellular protein domains (ECD) for which ligands are expressed in solid tumors. The ECD of CD40L was selected for combination with the ICD from the CD28 protein. With this approach, it was expected to not only provide co-stimulation and strengthen the TCR signaling, but also, through the CD40L ECD, facilitate the activation of tumor-resident antigen-presenting cells (APCs), modulate activation of tumor endothelium and induce TCR-MHC independent apoptotic effect on tumor cells. Since CD28 and CD40L belong to different classes of transmembrane proteins (type I and type II, respectively), creating a chimeric protein presented a structural and functional challenge. We present solutions to this challenge describing different CSP formats that were successfully expressed in human T cells along with an antigen-specific TCR. The level of surface expression of the CSPs depended on their distinct design and the state of T cell activation. In particular, CSPs were upregulated by TCR stimulation and downregulated following interaction with CD40 on target cells. Ligation of the CSP in the context of TCR-stimulation modulated intracellular signaling cascades and led to improved TCR-induced cytokine secretion and cytotoxicity. Moreover, the CD40L ECD exhibited activity as evidenced by effective maturation and activation of B cells and DCs. CD40L:CD28 CSPs are a new type of switch proteins designed to exert dual beneficial antitumor effect by acting directly on the gene-modified T cells and simultaneously on tumor cells and tumor-supporting cells of the TME. The observed effects suggest that they constitute a promising tool to be included in the engineering process of T cells to endow them with complementary features for improved performance in the tumor milieu.


Cells ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 382 ◽  
Author(s):  
Pradip De ◽  
Jennifer Carlson Aske ◽  
Nandini Dey

Three GTPases, RAC, RHO, and Cdc42, play essential roles in coordinating many cellular functions during embryonic development, both in healthy cells and in disease conditions like cancers. We have presented patterns of distribution of the frequency of RAC1-alteration(s) in cancers as obtained from cBioPortal. With this background data, we have interrogated the various functions of RAC1 in tumors, including proliferation, metastasis-associated phenotypes, and drug-resistance with a special emphasis on solid tumors in adults. We have reviewed the activation and regulation of RAC1 functions on the basis of its sub-cellular localization in tumor cells. Our review focuses on the role of RAC1 in cancers and summarizes the regulatory mechanisms, inhibitory efficacy, and the anticancer potential of RAC1-PAK targeting agents.


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