Biology subjects

Muzikansky, A.

Publications and source records attributed to Muzikansky, A..

4 recordsLinked to original sources

bioRxiv2024

Direct and abscopal anti-tumor responses elicited by peripheral nerve schwannoma irradiation synergize with anti-PD1 treatment in vestibular schwannoma models

NF2-related schwannomatosis (NF2-SWN) is a progressive and disabling disease requiring effective treatments. The hallmark of NF2-SWN is bilateral vestibular schwannomas (VSs), which progressively enlarge, leading to permanent sensorineural hearing loss and severely impacting patients quality of life. Currently, there are no FDA-approved drugs for VS or the associated hearing loss. Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, but have not yet been systematically investigated in non-malignant tumors such as VS. In our studies, we demonstrated that combining anti-PD1 (PD1) treatment with radiation therapy (RT) provides three significant therapeutic benefits: i) Enhanced PD1 efficacy and immune memory: RT induces immunogenic cell death and activates the STING pathway, enhancing PD1 efficacy and generating long-term immune memory, ii) Reduced RT dose and associated tissue injury: The combination strategy reduces the required RT dose necessary for effective tumor control, potentially minimizing RT injury to surrounding normal tissues, and iii) Elicited abscopal effects on cerebellopontine angle (CPA) schwannomas: RT to peripheral nerve tumor induces a systemic abscopal effect, which synergizes with PD-1 to effectively control intracranial schwannomas without direct irradiation, sparing the cochlea from radiation exposure and avoiding auditory radiation injury. Together, our findings provide a compelling rationale for deploying ICIs in combination with radiotherapy as a novel treatment approach for patients with VS and NF2-SWN.

cancer biology↗

bioRxiv2024

Enhanced Tumor Control and Hearing Loss Prevention Achieved with Combined Immune Checkpoint Inhibitor and Anti-VEGF Therapy in Vestibular Schwannoma Model

BackgroundNF2-related schwannomatosis (NF2-SWN) is a debilitating condition that calls for robust treatment options. The defining feature of NF2-SWN is the presence of bilateral vestibular schwannomas (VSs), which grow over time and can result in irreversible sensorineural hearing loss, significantly affecting the quality of life for those affected. At present, there are no FDA-approved medications specifically for treating VS or related hearing loss. VS management involves radiotherapy or surgical resection, while bevacizumab, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody (VEGF) may be used off-label in NF2-SWN to shrink the tumor. However, not all patients respond, and the effect is not always durable. There is a critical need for effective medications that can stop the growth of VS and prevent hearing loss associated with these tumors. While immune checkpoint inhibitors have transformed cancer therapy, their potential has not been thoroughly explored in non-malignant tumors such as VS. MethodsWe characterize the effects of anti-PD1 (PD1) treatment on tumor growth and hearing function in two syngeneic, immune-competent VS models. ResultsWe demonstrated that combining VEGF treatment with PD1 significantly enhances the efficacy of each monotherapy. Specifically, i) VEGF enhances PD1 efficacy by normalizing the tumor vasculature to improve drug delivery and immune cell infiltration, and by activating T cell and NK cell anti-tumor cytotoxicity via NKG2D upregulation; and ii) combining PD1 with VEGF treatment effectively controls tumors that progressed despite VEGF treatment. ConclusionThese findings provide a strong foundation for the development of PD1 with VEGF combination therapies for patients with NF2-SWN. Key pointsWe filled a critical gap in NF2 research: 1) we characterized the effects of immunotherapy on tumor growth and hearing function in non-malignant vestibular schwannomas 2) We showed combined anti-VEGF and anti-PD1 enhances the efficacy of each monotherapy Importance of the studyTreatment options for patients with NF2-SWN are limited or are associated with significant co-morbidities. There are no approved medical treatments for NF2-related tumors. While immune checkpoint inhibitors have transformed cancer therapy, their potential has not been thoroughly explored in non-malignant tumors such as VS. Our work filled this critical gap in NF2-SWN research. For the first time, we systemically evaluated ICI efficacy on tumor growth and hearing function in non-malignant schwannomas. Furthermore, we demonstrated that combining VEGF treatment with PD1 significantly enhances the efficacy of each monotherapy. Specifically: i) VEGF enhances PD1 efficacy by normalizing the tumor vasculature to improve drug delivery and immune cell infiltration, and by activating T cell and NK cell anti-tumor cytotoxicity via NKG2D upregulation; and ii) combining PD1 with VEGF treatment effectively controls tumors that progress despite VEGF treatment. Our findings provide a strong foundation for the development of PD1 with VEGF combination therapies for patients with NF2-SWN.

cancer biology↗

bioRxiv2023

Losartan rewires ovarian cancer tumor-immune microenvironment and suppresses IGF-1 to amplify chemo-immunotherapy sensitivity

Ovarian cancer (OvCa) is the most lethal of the gynecologic malignancies. Immune checkpoint inhibitors, which have revolutionized the treatment of multiple malignancies, have had limited efficacy in OvCa patients. Here, using syngeneic OvCa models and genetic and pharmacologic perturbations, we discovered that losartan - a widely prescribed anti-hypertensive drug - exhibits dual effects on both the tumor microenvironment and cancer cells to sensitize OvCa to chemo-immunotherapy. Specifically, losartan treatment i) reprograms the tumor microenvironment leading to increased vascular perfusion, and thus enhances drug delivery and immune effector cell intratumoral infiltration and function; and ii) rewires the OvCa cells by suppressing the IGF-1 signaling, resulting in enhanced chemosensitivity. As a result of the combined tumor and stromal effects, losartan treatment enhances the efficacy of chemo-immunotherapy in OvCa models. The safety and low cost (less than $1-2/day) of losartan warrant rapid translation of our findings to patients with OvCa.

cancer biology↗

bioRxiv2023

Co-Targeting IL-6 and EGFR signaling for the treatment of schwannomatosis and associated pain

Patients with Schwannomatosis (SWN) overwhelmingly present with intractable, debilitating chronic pain. There are no effective therapies to treat SWN. The drivers of pain response and tumor progression in SWN are not clear. The pain is not proportionally linked to tumor size and is not always relieved by tumor resection, suggesting that mechanisms other than mechanical nerve compression exist to cause pain. SWN research is limited by the lack of clinically-relevant models. Here, we established novel patient-derived xenograft (PDX) models, dorsal root ganglia (DRG) imaging model, and combined with single-cell resolution intravital imaging and RNASeq, we discovered: i) schwannomas on the peripheral nerve cause macrophage influx into the DRG, via secreting HMGB1 to directly stimulate DRG neurons to express CCL2, the key macrophage chemokine, ii) once recruited, macrophages cause pain response via overproduction of IL-6, iii) IL-6 blockade in a therapeutic setting significantly reduces pain but has modest efficacy on tumor growth, iv) EGF signaling is a potential driver of schwannoma growth and escape mechanism from anti-IL6 treatment, and v) combined IL-6 and EGFR blockade simultaneously controlled pain and tumor growth in SWN models. Our findings prompted the initiation of phase II clinical trial (NCT05684692) for pain relief in patients with SWN.

neuroscience↗