scholarly journals In vivo and in situ programming of tumor immunity by combining oncolytics and PD-1 immune checkpoint blockade

Author(s):  
Eric Bartee ◽  
Zihai Li
2020 ◽  
Vol 21 (21) ◽  
pp. 8035
Author(s):  
Yang Yang ◽  
Nhi Huynh ◽  
Chelsea Dumesny ◽  
Kai Wang ◽  
Hong He ◽  
...  

The anti-cancer effects of cannabinoids including CBD (Cannabidiol) and THC ((−)-trans-∆9-tetrahydrocannabinol) have been reported in the case of pancreatic cancer (PC). The connection of these cannabinoids to KRas oncogenes that mutate in more than 90% of PC, and their effects on PD-L1, a key target of immune checkpoint blockade, have not been thoroughly investigated. Using cell lines and mouse models of PC, the effects of CBD and THC on cancer growth, the interaction between PC cells and a stromal cell, namely pancreatic stellate cells (PSCs), and the mechanism(s) involved were determined by cell-based assays and mouse study in vivo. CBD and THC inhibited the proliferation of PC, PSC, and PSC-stimulated PC cells. They also suppressed pancreatic tumour growth in mice. Furthermore, CBD and/or THC reduced the expression of PD-L1 by either PC or PSC cells. Knockout of p-21 activated kinase 1 (PAK1, activated by KRas) in PC and PSC cells and, in mice, dramatically decreased or blocked these inhibitory effects of CBD and/or THC. These results indicated that CBD and THC exerted their inhibitions on PC and PSC via a p-21 activated kinase 1 (PAK1)-dependent pathway, suggesting that CBD and THC suppress Kras activated pathway by targeting PAK1. The inhibition by CBD and THC of PD-L1 expression will enhance the immune checkpoint blockade of PC.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e22012-e22012 ◽  
Author(s):  
Juan Vasquez ◽  
Anita Huttner ◽  
Lin Zhang ◽  
Asher Marks ◽  
Amy Chan ◽  
...  

e22012 Background: New treatments are needed to improve outcomes for pediatric gliomas. Immune checkpoint inhibitors are effective therapies in tumors with a high mutation burden that express multiple neo-antigens. However, for pediatric tumors that carry few mutations, there is a need to identify new antigenic targets of anti-tumor immunity. SOX2 is an embryonal stem cell antigen implicated in the biology of glioma initiating cells. Expression of SOX2 by pediatric glial tumors, and the capacity of the immune system in these patients to recognize SOX2, has not been studied. Methods: We examined the expression of SOX2 on paraffin-embedded tissue from pediatric glial tumors (n = 30). The presence of T cell immunity to SOX2 was examined in both blood and tumor-infiltrating T cells using antigen-dependent cytokine and T cell proliferation assays (n = 15). The nature of tumor-infiltrating immune cells in glial tumors (n = 4) was analyzed using single cell mass cytometry. Results: SOX2 is expressed by tumor cells but not surrounding normal tissue in all low grade gliomas (n = 15), high grade gliomas (n = 7), ependymomas (n = 3) and in 60% of oligodendrogliomas (n = 5). T cells against SOX2 can be detected in blood and tumor tissue in 33% of patients. CD4 and CD8 tumor infiltrating T-cells display a higher proportion of PD-1 expression compared to circulating T cells (p < 0.05). Glial CD4 and CD8 T cells are enriched for tissue resident memory phenotype (TRM; CD45RO+, CD69+, CCR7-) and the expression of PD-1 is primarily on these TRM cells (p < 0.05). A subset of CD4 and CD8 TRM cells also co-express multiple inhibitory checkpoints including PD-L1 and TIGIT. Glial tumors also contain NK cells with reduced expression of lytic granzyme (p < 0.05). Conclusions: Our data demonstrate in vivo immunogenicity of SOX2, which is specifically overexpressed on pediatric glial tumor cells. Our data also suggest that the TRM subset of tumor-infiltrating T cells may be key targets for immune checkpoint blockade, and harnessing tumor immunity will likely require the combined targeting of multiple inhibitory checkpoints. Future efforts to target SOX2 with dendritic cell vaccines combined with immune checkpoint blockade could provide effective tumor immunity and improve outcomes in pediatric brain tumors.


2019 ◽  
Vol 20 (1) ◽  
pp. 158 ◽  
Author(s):  
David J. Zahavi ◽  
Louis M. Weiner

Immune checkpoint blockade therapy is a powerful treatment strategy for many cancer types. Many patients will have limited responses to monotherapy targeted to a single immune checkpoint. Both inhibitory and stimulatory immune checkpoints continue to be discovered. Additionally, many receptors previously identified to play a role in tumor formation and progression are being found to have immunomodulatory components. The success of immunotherapy depends on maximizing pro-anti-tumor immunity while minimizing immunosuppressive signaling. Combining immune checkpoint targeted approaches with each other or with other receptor targets is a promising schema for future therapeutic regimen designs.


Oncogenesis ◽  
2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Min Zhou ◽  
Jianlong Yuan ◽  
Yaqi Deng ◽  
Xianqun Fan ◽  
Jianfeng Shen

AbstractMammalian SWI/SNF complex is a key chromatin remodeler that reshapes nucleosomes and regulates DNA accessibility. Mutations in SWI/SNF subunits are found in a broad spectrum of human cancers; however, the mechanisms of how these aberrations of SWI/SNF complex would impact tumorigenesis and cancer therapeutics remain to be elucidated. Studies have demonstrated that immune checkpoint blockade (ICB) therapy is promising in cancer treatment. Nevertheless, suitable biomarkers that reliably predict the clinical response to ICB are still lacking. Emerging evidence has suggested that SWI/SNF components play novel roles in the regulation of anti-tumor immunity, and SWI/SNF deficiency can be therapeutically targeted by ICB. These findings manifest the prominence of the SWI/SNF complex as a stratification biomarker that predicts treatment (therapeutic) response to ICB. In this review, we summarize the recent advances in ICB therapy by harnessing the cancer-specific vulnerability elicited by SWI/SNF deficiency. We provide novel insights into a comprehensive understanding of the underlying mechanisms by which SWI/SNF functions as a modulator of anti-tumor immunity.


2020 ◽  
Author(s):  
Mengyuan Li ◽  
Yuxiang Ma ◽  
You Zhong ◽  
Lei Qiang ◽  
Xiaosheng Wang

ABSTRACTBackgroundKALRN (kalirin RhoGEF kinase) is mutated in a wide range of cancers. Nevertheless, the association between KALRN mutations and the pathogenesis of cancer remains unexplored. The identification of biomarkers for cancer immunotherapy response is important considering that immunotherapies show beneficial effects only in a subset of cancer patients.MethodsWe explored the correlation between KALRN mutations and anti-tumor immunity in 10 cancer cohorts from The Cancer Genome Atlas (TCGA) program by the bioinformatics approach. Moreover, we verified the findings from bioinformatics analysis by in vitro experiments. Furthermore, we explored the correlation between KALRN mutations and immunotherapy response in four cancer cohorts receiving immune checkpoint blockade therapy.ResultsWe found that anti-tumor immune signatures were stronger in KALRN-mutated than in KALRN-wildtype cancers. Moreover, KALRN mutations correlated with increased tumor mutation burden and the microsatellite instability or DNA damage repair deficiency genomic properties which may explain the elevated anti-tumor immunity in KALRN-mutated cancers. Furthermore, we found that PD-L1 expression was significantly upregulated in KALRN-mutated versus KALRN-wildtype cancers. The enhanced anti-tumor immune signatures and PD-L1 expression in KALRN-mutated cancers may favor the response to immune checkpoint blockade therapy in this cancer subtype, as evidenced in four cancer cohorts receiving anti-PD-1/PD-L1/CTLA-4 immunotherapy. We further revealed that the significant association between KALRN mutations and increased anti-tumor immunity was attributed to that KALRN mutations compromised the function of KALRN target Rho GTPases on regulating DNA damage repair pathways.ConclusionsThe KALRN mutation is a useful biomarker for predicting the response to immunotherapy in cancer patients.


2021 ◽  
Vol 219 (1) ◽  
Author(s):  
Ensong Guo ◽  
Rourou Xiao ◽  
Yifan Wu ◽  
Funian Lu ◽  
Chen Liu ◽  
...  

Targeted therapies represent attractive combination partners with immune checkpoint blockade (ICB) to increase the population of patients who benefit or to interdict the emergence of resistance. We demonstrate that targeting WEE1 up-regulates immune signaling through the double-stranded RNA (dsRNA) viral defense pathway with subsequent responsiveness to immune checkpoint blockade even in cGAS/STING-deficient tumors, which is a typical phenotype across multiple cancer types. WEE1 inhibition increases endogenous retroviral elements (ERVs) expression by relieving SETDB1/H3K9me3 repression through down-regulating FOXM1. ERVs trigger dsRNA stress and interferon response, increasing recruitment of anti-tumor T cells with concurrent PD-L1 elevation in multiple tumor models. Furthermore, combining WEE1 inhibition and PD-L1 blockade induced striking tumor regression in a CD8+ T cell–dependent manner. A WEE1 inhibition–induced viral defense signature provides a potentially informative biomarker for patient selection for combination therapy with WEE1 and ICB. WEE1 inhibition stimulates anti-tumor immunity and enhances sensitivity to ICB, providing a rationale for the combination of WEE1 inhibitors and ICB in clinical trials.


Sign in / Sign up

Export Citation Format

Share Document