Biology subjects

Friedman, T.

Publications and source records attributed to Friedman, T..

4 recordsLinked to original sources

bioRxiv2021

BOXR1030, an anti-GPC3 CAR with exogenous GOT2 expression, shows enhanced T cell metabolism and improved antitumor activity

PurposeThe solid tumor microenvironment (TME) drives T cell dysfunction and inhibits the effectiveness of immunotherapies such as chimeric antigen receptor-based T cell (CAR T) cells. Early data has shown that modulation of T cell metabolism can improve intratumoral T cell function in preclinical models. Experimental DesignWe evaluated GPC3 expression in human normal and tumor tissue specimens. We developed and evaluated BOXR1030, a novel CAR T therapeutic co-expressing glypican-3 (GPC3)-targeted CAR and exogenous glutamic-oxaloacetic transaminase 2 (GOT2) in terms of CAR T cell function both in vitro and in vivo. ResultsExpression of tumor antigen GPC3 was observed by immunohistochemical staining in tumor biopsies from hepatocellular carcinoma, liposarcoma, squamous lung cancer, and Merkel cell carcinoma patients. Compared to control GPC3 CAR alone, BOXR1030 (GPC3-targeted CAR T cell that co-expressed GOT2) demonstrated superior in vivo efficacy in aggressive solid tumor xenograft models, and showed favorable attributes in vitro including an enhanced cytokine production profile, a less-differentiated T cell phenotype with lower expression of stress and exhaustion markers, an enhanced metabolic profile and increased proliferation in TME-like conditions. ConclusionsTogether, these results demonstrated that co-expression of GOT2 can substantially improve the overall antitumor activity of CAR T cells by inducing broad changes in cellular function and phenotype. These data show that BOXR1030 is an attractive approach to targeting select solid tumors. To this end, BOXR1030 will be explored in the clinic to assess safety, dose- finding, and preliminary efficacy (NCT05120271).

cancer biology↗

bioRxiv2021

Reovirus sensitizes microsatellite stable colorectal cancer to anti-PD-1 treatment via cross-talk in innate and adaptive immune systems

BackgroundMicrosatellite stable (MSS) colorectal cancer (CRC) represents ~85% of all CRCs. These tumors are poorly immunogenic and largely resistant to immunotherapy, necessitating a need to develop new immune enhancing strategies. Oncolytic reovirus has a high propensity to replicate in KRAS mutant tumors which account for ~50% of MSS CRCs. Current study explores the ability of reovirus to potentiate the effect of immune checkpoint inhibition in MSS CRC. MethodsEffectiveness of reovirus infection was quantified through MTT assay for cell viability, and expression of immune-response genes by flow cytometry, RT-qPCR, and microarray. Computational analysis of differentially expressed genes was performed by TAC, DAVID and STRING. Combinatorial approach using anti-PD-1 monoclonal antibody was assessed in ex vivo and in vivo models. Live-cell imaging, tumor volume and survival were measured for quantification of anti-tumor activity. Expression of pattern recognition receptors (PRRs), cell surface and activation markers of immune cells, and PD-1/PD-L1 axis were studied using multi-color flow cytometry, immunoblotting, immunohistochemistry, and immunofluorescence. ResultsReovirus infection exerted growth arrest and expression of immune-response genes in CRCs cell lines in a KRAS-dependent manner. However, microsatellite instability, rather than KRAS status determined immune-repose pathways, functionalities and biological processes post-reovirus infection. Furthermore, reovirus significantly enhanced the anti-tumor activity of anti-human PD-1 [nivolumab] treatment in MSS CRC cell lines ex vivo. Similarly, reovirus increased the activity of anti-mouse PD-1 treatment in the CT26 [MSS, KRASMut], but not the MC38 [MSI, KRASWt] syngeneic mouse model of CRC. Combinatorial treatment has reduced the proliferative index, increased apoptosis and differentially altered PD-L1/PD-1 signaling among CT26 and MC38 tumors. Activation of innate immune system and expression of PRRs and antigen presentation markers were observed under reovirus and anti-PD-1 treatment that additionally reduced immunosuppressive macrophages. This led to an increase in T cell subsets, increase in effector T cell activation, and decrease in exhaustion markers specifically within CT26 microenvironment. ConclusionThe current study systematically evaluates immune characteristics and immune microenvironment of CRC under reovirus/anti-PD-1 combination treatment that proves increased effectiveness among MSS compared to MSI CRCs. This is a promising regimen warranting translation into clinical trials. One Sentence SummaryOncolytic reovirus alters innate and adaptive immune system and potentiates MSS type colorectal cancer to checkpoint inhibition therapy.

cancer biology↗

bioRxiv2020

ER stress in the dorsal root ganglia regulates BK channel physiology and contributes to pain hypersensitivity in a mouse model of multiple sclerosis

Neuropathic pain is a common symptom of multiple sclerosis (MS) and current treatment options are ineffective. In this study, we investigated whether endoplasmic reticulum (ER) stress in dorsal root ganglia (DRG) contributes to pain hypersensitivity in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Inflammatory cells and increased levels of ER stress markers are evident in post-mortem DRGs from MS patients. Similarly, we observed ER stress in the DRG of mice with EAE and relieving ER stress with a chemical chaperone, 4-phenylbutyric acid (4-PBA), reduced pain hypersensitivity. In vitro, 4-PBA and the selective PERK inhibitor, AMG44, normalize cytosolic Ca2+ transients in putative DRG nociceptors. We went to assess disease-mediated changes in the functional properties of Ca2+-sensitive BK-type K+ channels in DRG neurons. We found that the conductance-voltage (GV) relationship of BK channels was shifted to a more positive voltage, together with a more depolarized resting membrane potential in EAE cells. Our results suggest that ER stress in sensory neurons of MS patients and mice with EAE is a source of pain and that ER stress modulators can effectively counteract this phenotype.

neuroscience↗

bioRxiv2019

The PMK-3 (p38) Mitochondrial Retrograde Response Functions in Intestinal Cells to Extend Life via the ESCRT Machinery.

The p38 mitogen-activated protein kinase (MAPK) PMK-3 controls a life-extending retrograde response in the nematode Caenorhabditis elegans that is activated following mitochondrial electron transport chain (ETC) disruption and is distinct from known longevity-promoting pathways. Here we show that the long isoform of PMK-3 expressed exclusively in the gut, rather than neurons, is sufficient to fully extend the life of animals exposed to mild ETC dysfunction. Surprisingly, constitutive activation of PMK-3 using a gain-of-function MAP3K/DLK-1 mutant does not extend the life of wild-type worms due to dampening of the DLK-1/PMK-3 signaling axis with age. We further show that core components of the ESCRT-III machinery, including ISTR-1, CHMP2B (CC01A4.2) and RAB-11.1, are required for life extension following ETC disruption. ESCRT proteins are needed for extracellular vesicle (EV) formation, lysosomal traffic and other functions requiring membrane encapsulation away from the cytoplasm. Together, our findings underscore PMK-3 as a pivotal factor controlling life extension in worms following mitochondrial ETC disruption and illustrate the importance of the endomembrane system to this process. Our findings raise the possibility that EVs may act as intra-organismal signaling vehicles to control aging.

pathology↗