Biology subjects

Sannigrahi, M. K.

Publications and source records attributed to Sannigrahi, M. K..

5 recordsLinked to original sources

bioRxiv2026

Therapeutic scheduling of WEE1 inhibition preserves T cell function and promotes immune control of HPV⁺ tumors

Human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV OPC) is driven by viral E6 and E7 oncoproteins, which disrupt G1 checkpoint control and impose selective dependency on WEE1-mediated G2/M regulation. While this vulnerability confers sensitivity to WEE1 inhibition, its immunologic consequences remain poorly defined, and the challenge of eliciting antitumor immunity without compromising immune fitness has limited clinical translation. Here, we show that WEE1 inhibition elicits durable antitumor immunity in immunocompetent models of HPV OPC. Using murine and human preclinical systems, we demonstrate that the WEE1 inhibitor azenosertib (ZN-c3) mediates tumor control through both cell-autonomous cytotoxicity and immune-dependent mechanisms requiring T cells and conventional dendritic cells. Mechanistically, HPV tumor cells are deficient in STING signaling and fail to mount canonical type I interferon responses. Instead, tumor cell-intrinsic cGAS drives immune activation through STING-competent host cells within the tumor microenvironment, revealing a non-cell-autonomous relay that circumvents viral immune evasion. Intermittent WEE1 inhibition preserves T cell fitness while maintaining antitumor efficacy, and mice achieving complete responses develop immunologic memory capable of rejecting tumor rechallenge. These findings establish intermittent WEE1 inhibition as an immune-permissive therapeutic strategy that enables antigen-specific T cell responses in HPV-driven malignancies and provides a mechanistic rationale for combination with immunotherapy.

cancer biology↗

bioRxiv2024

Association of oropharyngeal cancer recurrence with tumor-intrinsic and immune-mediated sequelae of reduced genomic instability

BackgroundLimited understanding of the biology predisposing certain human papillomavirus-related (HPV+) oropharyngeal squamous cell carcinomas (OPSCCs) to relapse impedes therapeutic personalization. We aimed to identify molecular traits that distinguish recurrence-prone tumors. Methods50 HPV+ OPSCCs that later recurred (cases) and 50 non-recurrent controls matched for stage, therapy, and smoking history were RNA-sequenced. Groups were compared by gene set enrichment analysis, and select differences were validated by immunohistochemistry. Features discriminating groups were scored in each tumor using gene set variation analysis, and scores were evaluated for recurrence prediction ability. ResultsCases downregulated pathways linked to anti-tumor immunity (FDR-adjusted p<.05) and contained fewer tumor-infiltrating lymphocytes (p<.001), including cytotoxic T-cells (p=.005). Cases also upregulated pathways related to cell division and other aspects of tumor progression. Upregulated and downregulated pathways were respectively used to define a tumor progression score (TPS) and immune suppression score (ISS) for each tumor. Correlation between TPS and ISS (r=.603, p<.001) was potentially explained by observed upregulation of DNA repair pathways in cases, which might enhance their progression directly and by limiting cytosolic DNA-induced inflammation. Accordingly, cases contained fewer double-strand breaks based on staining for phospho-RPA32 (p=.006) and {gamma}-H2AX (p=.005) and downregulated pro-inflammatory components of the cytoplasmic DNA sensing pathway. A combined score derived from TPS and ISS optimized recurrence prediction and stratified survival in a manner generalizable to three external cohorts. ConclusionsWe provide novel evidence that limiting genomic instability makes tumor-intrinsic and immune-mediated contributions to HPV+ OPSCC recurrence risk, opening opportunities to detect and target this treatment-resistant biology.

cancer biology↗

bioRxiv2022

Cancer type-specific prioritization strategy for targetable dependencies developed from the DepMap profile of head and neck cancer

ObjectivesThe DepMap genome-wide loss of function CRISPR screens offer new insight into gene dependencies in HPV(-) head and neck squamous cell carcinoma (HNSCC) cell lines. We aimed to leverage this data to guide preclinical studies by cataloging novel targetable dependencies that are predicted to offer a useful therapeutic window. We also aimed to identify targets potentially representing synthetic lethalities by testing for associations between genetic alterations and gene dependency profile. MethodsDepMap was queried for gene probability and effect scores in cell lines from 87 tumors, including 63 HPV(-) HNSCCs plus 24 esophageal squamous cell carcinomas (ESCCs), which have comparable etiology, tissue or origin, and genetic profile to HNSCC. A probability score of [≥] 0.5 was used as the threshold for essentiality. Essential genes were selected for analysis by 4 criteria: (1) presence in [≥]10% cell lines, (2) lack of common essential designation by DepMap, (3) lack of predicted dependency in normal cell lineages, and (4) designation as druggable by the Drug-Gene Interaction Database. ResultsThe 143 genes meeting selection criteria had a median gene effect score of 0.56. Selection criteria captured targets of standard therapeutic agents of HNSCC including TYMS (5-FU), tubulin genes (taxanes), EGFR (cetuximab), plus additional known oncogenes like PIK3CA and ERBB3. Functional classification analysis showed enrichment of tyrosine kinases, serine/threonine kinases, RNA-binding proteins, and mitochondrial carriers. 90% of the 143 dependencies were not known oncogenes in the OncoKB Database. 10% of targets had inhibitors previously used in a non-HNSCC phase II trial, including 8 that have not yet been tested in cancer. The 13 genes with median gene effect scores greater than of PIK3CA and not well-studied in HNSCC were assigned highest priority, including DHRSX, MBTPS1, TDP2, FARS2, TMX2, RAB35, CFLAR, GPX4, SLC2A1, TP63, PKN2, MAP3K11, and TIPARP. A novel association was found between NOTCH1 mutation and increased TAP1 dependency. ConclusionsThe DepMap CRISPR screens capture well-studied targets in HNSCC as well as numerous genes without known roles in HNSCC or malignancy in general. Several of these targets have well-developed inhibitors that provide resources to guide preclinical studies. Association of some of the dependencies with known molecular subgroups in HNSCC may enhance use of cell line models to guide personalization of therapy.

cancer biology↗

bioRxiv2022

Human papilloma virus E6 regulates therapy responses in oropharyngeal cancer by repressing the PGC-1α/ERRα axis

Therapy with radiation plus cisplatin kills human papilloma virus-related (HPV+) oropharyngeal squamous cell carcinomas (OPSCCs) by increasing reactive oxygen species beyond cellular antioxidant capacity. To explore why some patients fail these standard treatments, we evaluated whether the variation in HPV oncoprotein levels among HPV+ OPSCCs impacts mitochondrial metabolism, a source of antioxidant capacity. In cell line and patient-derived xenograft models, levels of HPV full-length E6 (fl-E6) inversely correlated with oxidative phosphorylation, antioxidant capacity, and therapy resistance, and fl-E6 was the only HPV oncoprotein to display such correlation. Ectopically expressing fl-E6 in models with low levels reduced mitochondrial mass, depleted antioxidant capacity, and sensitized to therapy. In this setting, fl-E6 repressed the PGC-1/ERR pathway for mitochondrial biogenesis by reducing p53-dependent PGC-1 transcription. Concordant observations were made in three clinical cohorts, where expression of mitochondrial components was higher in tumors of patients with reduced survival. These tumors contained the lowest fl-E6 levels, highest p53 target gene expression, and an activated PGC-1/ERR pathway. Our findings demonstrate that E6 can potentiate treatment responses by depleting mitochondrial antioxidant capacity and provide evidence for low E6 negatively impacting patient survival. E6s interaction with the PGC-1/ERR axis has implications for predicting and targeting treatment resistance in OPSCC.

cancer biology↗

bioRxiv2017

Molecular mechanism of cell-cell adhesion mediated by cadherin-23

Adherin-junctions are traditionally described by the homophilic-interactions of classical cadherin-proteins at the extracellular region. However, the role of long-chain non-classical cadherins like cadherin-23(Cdh23) is not explored as yet even though it is implicated in tissue-morphogenesis, cancer, and force-sensing in neuronal tissues. Here, we identified a novel antiparallel-binding interface of Cdh23 homodimer in solution by combining biophysical and computational methods, in-vitro cell-binding, and mutational modifications. The dimer consists of two electrostatic-based interfaces extended up to two terminal domains, atypical to classical-cadherins known so far, and forms the strongest interactions in cadherin-family as measured using single-molecule force-spectroscopy. We further identified single point-mutation, E78K, that completely disrupts this binding. Interestingly, the mutation, S77L, found in skin cancers falls within the binding interface of the antiparallel-dimer. Overall, we provide the molecular architecture of Cdh23 at the cell-cell junctions which are likely to have far-reaching applications in the fields of mechanobiology and cancer.

biophysics↗