Mesothelin

Overview

Mesothelin (MSLN) is a cell-surface protein that has attracted substantial biomedical interest as a tumor-associated target. It is expressed at low levels in normal tissues but is frequently overexpressed in several malignancies, making it a useful biomarker and therapeutic target in oncology. In recent research, mesothelin has been studied in the context of solid tumors as well as in acute myeloid leukemia, where its expression has been linked to disease behavior.

Biologically, mesothelin is relevant because it can participate in tumor cell adhesion and metastatic processes through interaction with MUC16. This interaction has been implicated in epithelial-mesenchymal transition-related biology and tumor immune regulation, and it has made mesothelin a focus for antibody-based imaging, CAR-T cell therapy, and other targeted immunotherapies. Its value as a target is also shaped by the fact that heterogeneous antigen expression can limit therapeutic efficacy, especially in solid malignancies.

Focus of Latest Publications

Recent publications show mesothelin emerging as a prominent target across both translational and bibliometric research. In a bibliometric and visual analytics study of chimeric antigen receptor T-cell immunotherapy in breast cancer, mesothelin was identified by burst detection analysis as a research frontier alongside tumor microenvironment (TME) and epithelial-mesenchymal transition. This suggests increasing attention to mesothelin in the context of resistance mechanisms and immune regulation in breast cancer.

In acute myeloid leukemia, mesothelin expression was reported to be detectable at both transcript and protein levels and to serve as an independent risk factor for extramedullary disease (EMD) in a cohort of 118 adult patients. The study concluded that mesothelin expression predicts a high risk of EMD by promoting cell adhesion and metastasis through interaction with MUC16. This extends mesothelin research beyond solid tumors and supports its relevance as a disease-associated marker in hematologic malignancy.

Mesothelin has also remained a major focus of cellular immunotherapy development. A recent report describing three Phase I studies highlighted distinct mesothelin-directed CAR-T cell therapies, underscoring the continued clinical development of this target. Another study noted that mesothelin-targeted CAR-T cell therapy can produce effective and long-lasting responses in tumors with high mesothelin expression, but may fail when antigen expression is heterogeneous. To address this limitation, membrane-bound TRAIL-armoring was investigated as a strategy to augment CAR-T cells in mesothelin-positive solid malignancies.

Imaging and patient selection have also been central themes. A study on an 89Zr-labeled antibody fragment for noninvasive detection of mesothelin-overexpressing tumors emphasized that multiple clinical trials of mesothelin-targeted antibodies have already provided preliminary evidence supporting clinical translation, and that patient screening is important for successful implementation. This reflects the growing role of mesothelin as both a therapeutic target and an imaging biomarker.

Across these studies, mesothelin has been linked to a broad range of tumor contexts, and has been discussed alongside pathways such as EGFR/SRC-mediated EMT and PIK3CA in the broader landscape of tumor progression and immune escape. Collectively, the recent literature positions mesothelin as a clinically actionable target with relevance to diagnosis, risk stratification, and immunotherapy design.

Key Publications

Jun Knowledge mapping and research trends of chimeric antigen receptor T-cell immunotherapy in breast cancer: A bibliometric and visual analytics study. (Human vaccines & immunotherapeutics, 2026, PMID 42316771): "In addition, burst detection analysis revealed that keywords including TME, "epithelial-mesenchymal transition," and "mesothelin" have gradually emerged as research frontiers, suggesting increasing attention to resistance mechanisms and tumor immune regulation."
Jun MSLN expression predicts a high risk of EMD in AML by promoting cell adhesion and metastasis via interaction with MUC16. (Blood advances, 2026, PMID 41824794): "Mesothelin (MSLN) expression, detectable at both transcript and protein levels, can serve as an independent risk factor for EMD in patients with AML."
Jun Trio of Phase I Studies Investigates Mesothelin-Directed CAR T-Cell Therapies. (Cancer discovery, 2026, PMID 42057455): "...investigating distinct mesothelin-targeted chimeric antigen receptor T-cell therapies..."
Jun Construction of a 89Zr-Labeled Specific Antibody Fragment for the Noninvasive Detection of Mesothelin-Overexpressing Tumors. (Molecular pharmaceutics, 2026, PMID 42117406): "Numerous clinical trials on mesothelin (MSLN)-targeted antibodies have provided preliminary evidence supporting their clinical translation, highlighting the importance of patient screening."
May Membrane-bound TRAIL-armoring augments CAR-T cells in mesothelin-positive solid malignancies. (Journal for immunotherapy of cancer, 2026, PMID 42167810): "Mesothelin (MSLN)-targeted chimeric antigen receptor (CAR)-T cell therapy shows an effective and long-lasting response in high MSLN-expressing tumors, but fails to treat tumors with heterogeneous levels of antigen expression."