Biology subjects

Yolmo, P.

Publications and source records attributed to Yolmo, P..

7 recordsLinked to original sources

bioRxiv2026

Hypoxia and epithelial to mesenchymal transition pathways are enriched in bladder tumor epithelium adjacent to tertiary lymphoid structures

Formation of tertiary lymphoid structures (TLS) within the bladder microenvironment because of chronic mucosal inflammation has been associated with variable clinical outcomes. While the immune cell composition and functional states of TLS have been characterized in both non-invasive and muscle-invasive bladder tumors, the TLS-adjacent tumor epithelial compartments remain poorly characterized. Evaluation of a 16-gene TLS signature in treatment-naive tumor bulk RNA sequencing profiles from 283 non-muscle invasive bladder tumors, from patients treated with Bacillus Calmette-Guerin (BCG) immunotherapy, and 348 muscle-invasive bladder tumors from patients treated with immune checkpoint inhibitor therapy revealed overlapping enrichment of immune exhaustion pathways. High TLS gene expression scores correlated with upregulation of immune exhaustion, hypoxia, and epithelial-to-mesenchymal transition (EMT) pathways in tumors from both cohorts. Spatial whole transcriptomic analysis of tumor sections with high TLS density, revealed enrichment of genes associated with EMT, angiogenesis, extracellular matrix remodeling, and B cell receptor signaling pathways in tumor epithelial regions adjacent to TLS, whereas those distant from TLS exhibited enrichment of IFN-{gamma}, TNF-/NF-{kappa}B, p53, and metabolic pathways. Multiplex immunofluorescence further identified co-localization of exhausted immune cell populations within the core and periphery of peri-tumoral TLS. These findings indicate that a pro-tumorigenic microenvironment associated with disease progression in bladder cancer exists within peri-tumoral TLS and potentially a factor underlying contrasting therapeutic associations potentially driven by live microbial versus targeted immunomodulatory therapy in NMIBC and MIBC.

cancer biology↗

bioRxiv2026

Systemic and tumor intrinsic expansion of FCRL5 expressing B cells associates with poor response to Bacillus Calmette-Guerin immunotherapy in patients with non-muscle invasive bladder cancer

The majority of patients treated with Bacillus Calmette-Guerin (BCG) immunotherapy, for non-muscle invasive bladder cancer (NMIBC), experience early recurrence due to pre-existing mucosal immune dysfunction. Since B cell are mucosal immune sentinels, we characterized the systemic and local B cell responses in 45 patients with NMIBC. Expansion of circulating atypical B cells (ABCs) following repeated BCG instillation, expanded IgG autoantibody repertoire, progressive IgG reactivity against BCG antigens, and higher tumor IgG deposition, were features of patients who recurred early. Integrated spatial immunophenotyping and single cell spatial transcriptomic analysis of corresponding tumors revealed increased ABCs within tertiary lymphoid structures, and co-localization with PD-1 B cells, regulatory T cells, and CD163 macrophages. Independent validation in two patient cohorts (total n = 409), revealed a significant association between high expression of the ABC specific, FCRL5, and poor outcomes. Our study identifies ABCs as key mediators of poor response to BCG in patients with high-risk NMIBC.

cancer biology↗

bioRxiv2025

Contributions of T helper 9 cells in endometriosis-associated inflammation and lesion growth

Endometriosis is an inflammatory gynaecologic disease characterized by ectopic growth of endometrial-like tissue, resulting in pelvic pain and infertility. T-helper 9 (Th9) cells play a known role in various chronic inflammatory diseases. Despite parallels between endometriosis and Th9-driven diseases, their role in endometriosis has not been explored. We investigated Th9 cell involvement in endometriosis pathophysiology using human tissue samples, in vitro experiments with human-derived Th9 cells, and in vivo experiments to shed insight on the impact of adoptively transferred Th9 cells in our established syngeneic endometriosis mouse model. Immunohistochemistry of a tissue microarray revealed significantly increased interleukin-9 (IL-9)-positive cells in patient lesions compared to control endometrium. Human CD4+ Th cells purified from peripheral blood mononuclear cells treated with Th9-driving growth factors produced significantly increased pro-inflammatory mediators, including IL-5, IL-9 and IL-13, in response to estrogen stimulation. Adoptive transfer of murine Th9-like cells increased plasma IL-1 concentration and altered transcriptional profiles of several signalling pathways, including Notch and PI3K-Akt. Immunofluorescent microscopy depicted adoptively transferred Th9 cells present within mouse lesions. Furthermore, immunohistochemical analysis demonstrated reduced lesion proliferation following Th9-adoptive transfer. This study provides the first evidence that Th9 cells likely promote immune-inflammatory alterations within lesions to exacerbate disease.

immunology↗

bioRxiv2023

Increased stromal densities of B cells, CD103+ cells, and CD163+ M2-like macrophages associate with poor clinical outcomes in BCG treated non-muscle invasive bladder cancer

Non-muscle invasive bladder cancer (NMIBC) constitutes a significant clinical challenge, with over 50% of patients experiencing poor clinical outcomes in the form of early recurrence or progression following treatment with Bacillus Calmette-Guerin (BCG) immunotherapy. The pre-treatment tumor immune microenvironment (TIME) is an established determinant of response to BCG. This study explores the spatial profiles of CD79a+ B cells, CD163+ M2-like macrophages, proliferating and tissue-resident phenotypes of T cells, along with PD-1/PD-L1 checkpoint expression in pre-BCG treatment tumors of 173 patients (139 males, 34 females). Multiplex immunofluorescence staining of a tumor tissue microarray, revealed elevated infiltration of CD79a+ B cells, CD163+ M2-like macrophages, CD103+ cells, and CD8+ T cells at the tumor invasive margins. Increased epithelial PD-L1 immune-checkpoint expression in tumors was observed in female and male patients who exhibited significantly shorter recurrence-free survival (RFS). Importantly, high CD79a+ B cell density in BCG-treated females in both stromal and epithelial compartments exhibited significantly shorter RFS and progression-free survival compared to males. Stromal CD79a+ B cell density was positively correlated with M2-like macrophages, CD8+ T cells, CD103+ cells and PD-1 expressing cells. CD79a+ B cells, CD103+ cells, and M2-like macrophage density were associated with higher grade and enriched in basal subtype tumor. This study highlights the significance of an understudied role of B cells and their cellular neighborhoods in the pre-treatment TIME and BCG-therapy response. Overall, findings from this study underscore the importance of considering sex-related immunobiological differences in the stromal compartments of bladder tumors towards the development of optimal therapeutic targeting strategies.

cancer biology↗

bioRxiv2023

Endocannabinoids and their receptors modulate endometriosis pathogenesis and immune response

Endometriosis (EM), characterized by the presence of endometrial-like tissue outside the uterus, is the leading cause of chronic pelvic pain and infertility in females of reproductive age. Despite its high prevalence, the molecular mechanisms underlying EM pathogenesis remain poorly understood. The endocannabinoid system (ECS) is known to influence several cardinal features of this complex disease including pain, vascularization, and overall lesion survival, but the exact mechanisms are not known. Utilizing CNR1 knockout (k/o), CNR2 k/o and wild type (WT) mouse models of EM, we reveal contributions of ECS and these receptors in disease initiation, progression, and immune modulation. Particularly, we identified EM-specific T cell dysfunction in the CNR2 k/o mouse model of EM. We also demonstrate the impact of decidualization- induced changes on ECS components, and the unique disease-associated transcriptional landscape of ECS components in EM. Imaging Mass Cytometry (IMC) analysis revealed distinct features of the microenvironment between CNR1, CNR2, and WT genotypes in the presence or absence of decidualization. This study, for the first time provides an in-depth analysis of the involvement of the ECS in EM pathogenesis and lays the foundation for the development of novel therapeutic interventions to alleviate the burden of this debilitating condition.

immunology↗

bioRxiv2022

Carcinogen induced expansion of atypical B cells and pre-treatment tumor adjacent tertiary lymphoid structures associate with poor response to BCG in non-muscle invasive bladder cancer

Poor response to Bacillus Calmette-Guerin (BCG) immunotherapy remains a major barrier in the management of patients with non-muscle-invasive bladder cancer (NMIBC). Among the multiple factors contributing to poor outcomes, a B cell infiltrated pre-treatment immune microenvironment of NMIBC tumors has emerged as a key determinant of response to BCG. The mechanisms underlying the paradoxical roles of B cells in NMIBC are poorly understood. Here, we show that B cell dominant tertiary lymphoid structures (TLSs), a hallmark feature of chronic mucosal immune response, are abundant and located close to the epithelial compartment in pre-treatment tumors from BCG non-responders. Digital spatial proteomic profiling of whole tumor sections revealed higher expression of immune exhaustion-associated proteins within the TLSs from both responders and non-responders. Chronic local inflammation, induced by the N-butyl- N-(4-hydroxybutyl) nitrosamine (BBN) carcinogen, led to TLS formation with recruitment and differentiation of the immunosuppressive atypical B cell (ABCs) subset within the bladder microenvironment, predominantly in aging female mice compared to their male counterparts. Depletion of ABCs simultaneous to BCG treatment delayed cancer progression in female mice. Our findings provide the first evidence indicating the role of ABCs in BCG response and will inform future development of therapies targeting the B cell exhaustion axis.

cancer biology↗

bioRxiv2021

The influence of age and sex on the pre-treatment immune microenvironment of a carcinogen induced murine model of bladder cancer

The incidence of urothelial carcinoma of the bladder is four times higher in males than females; however, females tend to present with a more aggressive disease, a poorer response to immunotherapy and suffer worse clinical outcomes. Recent findings have demonstrated sexual dimorphism in the tumor immune microenvironment of non-muscle invasive bladder cancer and associated clinical outcomes. However, a significant gap in knowledge remains with respect to the current pre-clinical modeling approaches and more precisely recapitulating these differences towards improved therapeutic design. Based on the similarities in mucosal immune physiology between humans and mice, we evaluated the sex and age-related immune alterations in healthy murine bladders. Bulk-RNA sequencing and multiplex immunofluorescence based spatial immune profiling of healthy murine bladders from male and female mice of age groups spanning young to old showed a highly altered immune landscape that exhibited sex and age associated differences, particularly in the context of B cell associated responses. Spatial profiling using markers specific to macrophages, T lymphocytes, B lymphocytes, activated dendritic cells, high endothelial venules, myeloid cells and the PD-L1 immune checkpoint showed sex and age associated differences. Bladders from healthy older female mice showed a higher number of tertiary lymphoid structures (TLSs) compared to both young female and male equivalents. Spatial immune profiling of N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) carcinogen exposed male and female bladders from young and old mice revealed a similar frequency of TLS formation, sex differences in the bladder immune microenvironment and, age differences in latency of tumor induction. These findings support the incorporation of sex and age as factors in pre-clinical modeling of NMIBC and will potentially advance the field of immunotherapeutic drug development to improve clinical outcomes in NMIBC.

cancer biology↗