Publications by authors named "Nourhan El Ahmar"

Immune checkpoint inhibitors can lead to 'exceptional', durable responses in a subset of persons. However, the molecular basis of exceptional response (ER) to immunotherapy in metastatic clear cell renal cell carcinoma (mccRCC) has not been well characterized. Here we analyzed pretherapy genomic and transcriptomic data in treatment-naive persons with mccRCC treated with standard-of-care immunotherapies: (1) combination of programmed cell death protein and ligand 1 (PD1/PDL1) and cytotoxic T lymphocyte-associated protein 4 inhibitors (IO/IO) or (2) combination of PD1/PDL1 and vascular endothelial growth factor (VEGF) receptor inhibitors (IO/VEGF).

View Article and Find Full Text PDF

The advent of spatial transcriptomics and spatial proteomics have enabled profound insights into tissue organization to provide systems-level understanding of diseases. Both technologies currently remain largely independent, and emerging same slide spatial multi-omics approaches are generally limited in plex, spatial resolution, and analytical approaches. We introduce IN-situ DEtailed Phenotyping To High-resolution transcriptomics (IN-DEPTH), a streamlined and resource-effective approach compatible with various spatial platforms.

View Article and Find Full Text PDF

Renal cell carcinoma with sarcomatoid differentiation (sRCC) is associated with poor survival and a heightened response to immune checkpoint inhibitors (ICIs). Two major barriers to improving outcomes for sRCC are the limited understanding of its gene regulatory programs and the low diagnostic yield of tumor biopsies due to spatial heterogeneity. Herein, we characterized the epigenomic landscape of sRCC by profiling 107 epigenomic libraries from tissue and plasma samples from 50 patients with RCC and healthy volunteers.

View Article and Find Full Text PDF

Purpose: Programmed cell death protein 1 (PD-1) expression on CD8+TIM-3-LAG-3- tumor-infiltrating cells predicts positive response to PD-1 blockade in metastatic clear-cell renal cell carcinoma (mccRCC). Because inhibition of PD-1 signaling in regulatory T cells (Treg) augments their immunosuppressive function, we hypothesized that PD-1 expression on tumor-infiltrating Tregs would predict resistance to PD-1 inhibitors.

Experimental Design: PD-1+ Tregs were phenotyped using multiparametric immunofluorescence in ccRCC tissues from the CheckMate-025 trial (nivolumab: n = 91; everolimus: n = 90).

View Article and Find Full Text PDF
Article Synopsis
  • HHLA2 is an immune checkpoint associated with kidney cancer and other tumors, and understanding its expression regulation is key for developing targeted therapies.
  • HHLA2 expression is found in primary kidney tumors but decreases in vitro, while it can be induced in vivo under specific tumor microenvironment conditions.
  • Only certain cytokines like IL-10 and BMP4 can modestly enhance HHLA2 expression in immune cells, indicating complex regulation involving tumor and immune cell interactions.
View Article and Find Full Text PDF

Recent advances in our understanding of the molecular alterations underlying different types of renal cell carcinoma (RCC), as well as the implementation of immune checkpoint inhibitors in the treatment of patients with advanced disease, have significantly expanded the role of pathologists in the management of RCC patients and in the identification of predictive biomarkers that can guide patient treatment. In this chapter, we examine pathologists' evolving role in patient care and the development of precision medicine strategies for RCC.

View Article and Find Full Text PDF