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Frederick, M. J.

Publications and source records attributed to Frederick, M. J..

5 recordsLinked to original sources

Targeted suppression of SPP1 inhibits tumor invasion and metastasis in NRF2 hyperactivated cisplatin resistant HNSCC

PurposeCisplatin is the gold standard systemic agent for definitive treatment of HNSCC. The purpose of this study was to investigate the role of SPP1 in the progression and metastasis of cisplatin-resistant HNSCC, particularly in the context of NRF2 hyperactivation. Experimental DesignCDDP resistant HNSCC cell lines stably expressing various shRNA SPP1 constructs were generated. Clonogenic survival assays and a mouse model of oral cancer were used to examine the impact of silenced SPP1 in vitro and in vivo on CDDP sensitivity and tumor progression. Western blotting, cell invasion, functional proteomics RPPA and spatial transcriptomic analyses were performed to identify molecular interactions and metastatic signaling pathways. ResultsTargeted suppression of SPP1 improved cisplatin sensitivity, inhibited tumor invasion and metastasis in vitro and in vivo as well as several metastatic signaling proteins in NRF2- hyperactivated HNSCC. Spatial transcriptomic analysis revealed a potential mechanistic interaction between SPP1, integrins and CD44 receptors in primary and metastatic HNSCC. Spatial annotation and enrichment analyses using HALLMARK revealed gene set signatures of interferon and EMT present in cell clusters with SPP1 expression in both the primary tumor and lung metastases. Finally, increased expression of SPP1 was found to be poor prognostic factor and significantly correlated with NFE2L2/KEAP1 mutational status and higher tumor grade in HNSCC patients. ConclusionsTargeting dysregulated SPP1 improved cisplatin sensitivity, inhibited tumor invasion and metastasis in NRF2-hyperactivated HNSCC. These findings highlight the therapeutic potential of targeting SPP1 and the need for developing specific SPP1 inhibitors to improve outcomes for patients with HNSCC. Translational RelevanceCisplatin-based chemotherapy remains the standard of care for patients with locally advanced head and neck squamous cell carcinoma. Cisplatin resistance often leads to treatment failure and metastasis which accounts for the majority of mortality associated with this disease. Unfortunately, there are no effective therapeutic agents to overcome cisplatin resistance in HNSCC. Here, we present compelling evidence that targeting SPP1 (also known as osteopontin) inhibits cisplatin resistance, tumor progression and metastasis in NRF2-hyperactivated HNSCC, positioning it as a potential therapeutic target to improve treatment outcomes in HNSCC.

cancer biology↗

NOTCH1 Acts as a Tumor Suppressor That Induces Early Differentiation in Head and Neck Cancer

We identified frequent inactivating notch1 mutations in HNSCC over a decade ago, indicating its role as a tumor suppressor--unlike its oncogenic function in leukemias and salivary gland tumors. However, there has been much debate in the literature regarding a possible oncogenic role in HNSCC as well, based on reports that notch1 signaling drives tumor growth and a cancer stem cell phenotype in some HNSCC tumor lines and patient samples. Clarifying whether NOTCH1 occasionally functions as an oncogenic driver in HNSCC is crucial to the prognosis and personalized therapy of patients with either wild-type or mutated NOTCH1. Here we present a systematic and comprehensive investigation unequivocally demonstrating that notch1 signaling functions as a tumor suppressor in HNSCC regardless of mutation or activation status and leads to reduction in frequency of cancer stem cells. We develop a robust gene expression signature of notch1 activation based on experimental data that when applied to patient samples shows notch1 signaling is associated with very early differentiation, an altered tumor microenvironment, and better prognosis-- consistent with a tumor suppressive role. Our work unifies the field by reconciling conflicting data and providing critical insights into the biological and clinical significance of the NOTCH1 pathway in HNSCC.

cancer biology↗

Bypassing cisplatin resistance in Nrf2 hyperactivated head and neck cancer through effective PI3Kinase targeting

BackgroundFor patients with head and neck squamous cell carcinoma (HNSCC), failure of definitive radiation combined with cisplatin nearly universally results in death. Although hyperactivation of the Nrf2 pathway can drive radiation and cisplatin resistance along with suppressed anti-tumor immunity, treatment-refractory HNSCC tumors may retain sensitivity to targeted agents secondary to synergistic lethality with other oncogenic drivers (e.g., NOTCH1 mutations). PurposeWe evaluated the efficacy of PI3K inhibitors (PI3Ki) in bypassing Nrf2-mediated cisplatin resistance in HNSCC. MethodsWe measured transcriptomic, metabolomic and signaling changes driven by PI3Kis in cisplatin-resistant HNSCCs in vitro and tested efficacy in vivo in subcutaneous, orthotopic and metastatic xenograft models using immunodeficient and humanized murine models of HNSCC coupled with spatial transcriptomics. ResultsThe PI3K pathway is activated in Nrf2-driven cisplatin-resistant HNSCC and is suitable for blockade as demonstrated in an in vivo shRNA screen. The PI3Ki gedatolisib inhibits cisplatin-resistant HNSCC proliferation, induces G2M arrest and potentiates cisplatin effectiveness through activation of autophagy, senescence and disruption of fatty acid metabolism. Gedatolisib suppresses HNSCC tumor growth in orthotopic and metastatic settings and demonstrates profound anti-tumor activity in humanized murine models of HNSCC, coupled with a reduction in hypoxia-rich regions and reduced infiltration by regulatory T lymphocytes. ConclusionOur findings emphasize the critical role of the PI3K-AKT-mTOR pathway in cisplatin-resistant HNSCC and highlight the therapeutic potential of PI3K inhibitors. Gedatolisib induced metabolic regulation and substantial re-sensitization of resistant cells to cisplatin, positioning it as a promising candidate for combination therapies aimed at overcoming primary chemo-radiation failure in HNSCC. Statement of translational relevanceCisplatin resistance, whether intrinsic or acquired, translates to treatment failure and nearly universal death in head and neck squamous cell carcinoma (HNSCC). However, the development of effective systemic regimens for cisplatin-resistant HNSCC has not yet been successful. Here, we present, for the first time, a mechanistic, biomarker-informed strategy for effective targeting of the PI3Kinase pathway in cisplatin-resistant HNSCC with substantial anti-tumor activity in both orthotopic and metastatic models, which may be capable of bypassing or reversing cisplatin resistance in this disease.

cancer biology↗

Tobacco smoke exposure is a driver of altered oxidative stress response and immunity in head and neck cancer

PurposeExposomes are critical drivers of carcinogenesis. However, how they modulate tumor behavior remains unclear. Extensive clinical data link cigarette smoke as a key exposome that promotes aggressive tumors, higher rates of metastasis, reduced response to chemoradiotherapy, and suppressed anti-tumor immunity. We sought to determine whether smoke itself can modulate aggressive tumor behavior in head and neck squamous cell carcinoma (HNSCC) through reprogramming the cellular reductive state. Experimental designUsing established human and murine HNSCC cell lines and syngeneic mouse models, we utilized conventional western blotting, steady state and flux metabolomics, RNA sequencing, quantitative proteomics and flow cytometry to analyze the impact of smoke exposure on HNSCC tumor biology. ResultsCigarette smoke persistently activated Nrf2 target genes essential for maintenance of the cellular reductive state and survival under conditions of increased oxidative stress in HNSCC regardless of HPV status. In contrast to e-cigarette vapor, conventional cigarette smoke mobilizes cellular metabolism toward oxidative stress adaptation, resulting in development of cross-resistance to cisplatin. In parallel, smoke exposure modulates both expression of PDL1 and the secretory phenotype of HNSCC cells through activation of NF-{kappa}B resulting in an altered tumor immune microenvironment (TIME) in syngeneic mouse models and altered PBMC differentiation that includes downregulated expression of antigen presentation and costimulatory genes in myeloid cells. ConclusionCigarette smoke exposome is a potent activator of the Nrf2 pathway and is a likely primary trigger for the tripartite phenotype of aggressive HNSCC consisting of: 1) reduced chemotherapy sensitivity, 2) enhanced metastatic potential and 3) suppressed anti-tumor immunity. Statement of significanceThe smoke exposome drives aggressive tumor behavior, treatment resistance and suppressed immunity through coordinated metabolic reprogramming. Successfully targeting this adaptation is critical to improving survival in smokers with head and neck cancer.

cancer biology↗

CREBBP/EP300 mutation is associated with poor outcome in HNSCC and targetable with synthetic cytotoxicity.

Despite radiation forming the curative backbone of over 50% of malignancies, there are no genomically-driven radiation sensitizers for clinical use. We performed in vivo shRNA screening to identify targets generally associated with radiation response as well as those exhibiting a genomic dependency. This identified the histone acetyltransferases CREBBP/EP300 as a target for radiosensitization in combination with radiation in cognate mutant tumors. Further in vitro and in vivo studies confirmed this phenomenon was due to repression of homologous recombination following DNA damage and can be reproduced using chemical inhibition of histone acetyltransferase (HAT), but not bromodomain function. Selected mutations in CREBBP lead to a hyperacetylated state that increases CBP and BRCA1 acetylation, representing a gain of function targets by HAT inhibition. Additionally, mutations in CREBBP/EP300 were associated with recurrence following radiation, in several squamous cell carcinoma cohorts. These findings represent both a novel mechanism of treatment resistance and the potential for genomically-driven treatment.

cancer biology↗