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Biology subjects

Ferris, R. L.

Publications and source records attributed to Ferris, R. L..

5 recordsLinked to original sources

ATR kinase inhibitors induce mitochondrial fission in CD8+ T cells and impair immune memory in vivo

The DNA damage response kinase ATR restrains CDK1 activity during S and G2 phases of the cell cycle, confining CDK1-driven processes to mitosis. ATR kinase inhibitors were originally developed to potentiate chemotherapy-induced DNA damage at stalled replication forks and to disrupt DNA damage-induced cell cycle checkpoints. Recent evidence, however, reveals that these inhibitors also disrupt cell cycle organization in cells that have not sustained any DNA damage. We show that ATR kinase inhibitors potently trigger unscheduled mitochondrial fission, causing loss of mitochondrial mass in actively dividing CD8+ T cells that persists in memory CD8+ T cells. Moreover, ATR inhibition during the peak of CD8+ T cell expansion in a mouse model of LCMV Armstrong infection impairs the formation of immune memory. These findings carry significant clinical implications. ATR kinase inhibitors are currently being evaluated in clinical trials in combination with chemotherapy, radiation, and immune checkpoint inhibitors in patients where anti-tumor immune responses are recognized as a determinant of durable response. Our results identify an unexpected consequence of ATR inhibition that disrupts cellular metabolism with broad implications for both preclinical research and clinical application.

cancer biology↗

Integrating Artificial Intelligence-Driven Digital Pathology and Genomics to Establish Patient-Derived Organoids as a Novel Alternative Model for Drug Response in Head and Neck Cancer

Patient-derived organoids (PDOs) are emerging as advanced 3D ex vivo novel alternative method (NAM) preclinical models, offering significant advantages over traditional cell lines and monolayer cultures for therapeutic development. In this study, we established PDOs from surgically resected fresh tissues of human papillomavirus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) across anatomical sites, tumor T-categories, and sample types. These PDOs faithfully recapitulate the tumors pathology, mutational profile, and drug response. To enable rapid classification of PDO identity, we developed a new convolutional neural network (CNN) model, TransferNet-PDO, which accurately distinguished tumor versus normal PDOs in culture using digital histopathology images (AUC[≥]0.88). PDOs maintained stable cultures and were cryopreserved between passages 5 and 12. Immunohistochemistry (IHC) staining (PanCK, p63, Cytokeratin 13, Ki67) confirmed squamous phenotype and histologic aggression of the original tumor. For tumors harboring TP53 mutations by whole-exome sequencing (WES), PDOs retained the corresponding p53 functional status as confirmed by IHC (enhanced or loss of expression). Somatic mutational landscape revealed that PDOs preserved driver somatic mutations, copy number variations (CNVs), and clonal architecture including low-prevalence subclones. Drug sensitivity assessment of PDOs showed that cisplatin reduced cell viability, whereas cetuximab and lenvatinib had minimal effects. Chemoradiation led to greater tumor organoid killing compared to radiation or chemotherapy alone. This study presents an integrated HNSCC PDO platform combining tissue biobanking, organoid establishment, multi-omics characterization, functional drug screening, and AI-driven histopathologic classification, providing a comprehensive and scalable system for translational cancer research.

cancer biology↗

Expression of Tim-3 drives naive Treg to an effector-like state with enhanced suppressive activity

Regulatory T cells (Treg) are critical mediators of self-tolerance but can also limit effective anti-tumor immunity. We and others previously reported that 40-60% percent of Treg-infiltrating head and neck cancer (HNC) and other tumors highly express Tim-3, compared with about 5% in lymphoid organs. Tumor-infiltrating Tim-3+ Treg also have enhanced suppressive function and display a more effector-like phenotype. Using a novel mouse model with cell type-specific Tim-3 expression, we show here that expression of Tim-3 by Treg is sufficient to drive Treg to a more effector-like phenotype, resulting in enhanced suppressive activity and increased tumor growth. These findings may help to reconcile previous reports that some Tim-3 antibodies enhance T cell responses in vivo, while expression of Tim-3 has a cell-intrinsic ability to enhance TCR signaling and T cell activation. Thus, we propose that Tim-3 regulates anti-tumor immunity at least in part through enhancement of Treg function. To our knowledge, this is the first example in which expression of a single co-stimulatory molecule is sufficient to drive differentiation of Treg in this manner.

immunology↗

Divergent cancer etiologies drive distinct B cell signatures and tertiary lymphoid structures

Current immunotherapy paradigms aim to reinvigorate CD8+ T cells, but the contribution of humoral immunity to antitumor immunity remains understudied1,2. Head and neck squamous cell carcinoma (HNSCC) is caused by either human papillomavirus (HPV+) or environmental carcinogens (i.e. tobacco and alcohol; HPV-)3,4. Here, we demonstrate that HPV+ HNSCC patients have transcriptional signatures of germinal center (GC) tumor infiltrating B cells (TIL-Bs) and spatial organization of immune cells consistent with GC-like tertiary lymphoid structures (TLS), both of which correlate with favorable outcomes in HNSCC patients. Further, our single-cell RNAseq data also indicate that GC TIL-Bs are characterized by distinct waves of gene expression consistent with dark zone, light zone and a transitional state of GC B cells. High-dimensional spectral flow cytometry permitted in depth characterization of activated, memory and GC TIL-Bs. Further, single cell RNAseq analysis and subsequent protein validation identified a role for semaphorin 4a (Sema4a) in the differentiation of GC TIL-Bs and indicated that expression of Sema4a was enhanced on GC TIL-Bs and within GC-like TLS in the TME. Thus, in contrast to some reports on the detrimental role of TIL-Bs in human tumors, our findings suggest that TIL-Bs play an instrumental role in antitumor immunity5,6. Novel therapeutics to enhance TIL-B responses in HNSCC should be prioritized as a compliment to current T-cell mediated immunotherapies.

immunology↗

Systemic immune dysfunction in cancer patients driven by IL6 and IL8 induction of an inhibitory receptor module in peripheral CD8+ T cells

Many cancer patients do not develop a durable response to the current standard of care immunotherapies despite substantial advances in targeting immune inhibitory receptors1-5. A potential compounding issue, which may serve as an unappreciated, dominant resistance mechanism, is an inherent systemic immune dysfunction that is often associated with advanced cancer6-12. Minimal response to inhibitory receptor (IR) blockade therapy and increased disease burden have been associated with peripheral CD8+ T cell dysfunction, characterized by suboptimal T cell proliferation and chronic expression of IRs (eg. Programmed Death 1 [PD1] and Lymphocyte Activation Gene 3 [LAG3])13, 14. Here, we demonstrate that up to a third of cancer patients express robust intracellular LAG3 (LAG3IC), but not surface LAG3 (LAG3SUR), in peripheral CD8+ T cells compared to CD4+ T cells and regulatory T cells (Tregs). LAG3IC is associated with: (i) expression of a LAG3IC-dominant IR module that includes PD1IC, NRP1IC, CD39IC, and TIGITIC; (ii) decreased CD8+ but not CD4+ T cell function that can be reversed by anti-LAG3 (and/or anti-PD1), despite limited constitutive surface IR expression; and (iii) poor disease prognosis. Systemic immune dysfunction is restricted to CD8+ T cells, including a high percentage of peripheral naive CD8+ T cells, indicating a TCR-independent mechanism that is driven by the cytokine IL6 and the chemokine IL8. Thus, the combination of an increased LAG3-dominant IR module and elevated systemic IL6 and/or IL8 may serve as predictive biomarkers and increase the possibility that cancer patients will benefit from therapeutic combinations targeting these systemic cytokines in the setting of PD1 and/or LAG3 blockade.

cancer biology↗