TROP2 Drives Hypopharyngeal Cancer Growth by Blocking Pyroptosis Through PI3K/AKT

Hypopharyngeal squamous cell carcinoma, an aggressive cancer of the throat with an extremely poor prognosis, may owe part of its lethality to a single cell-surface protein. A new study reports that TROP2, a molecule already known to be highly expressed in this tumor type, actively suppresses a form of inflammatory cell death called pyroptosis, allowing cancer cells to survive and spread. The work, published in Cancer Cell International, maps out a signaling chain that runs from a transcription factor named JUND through TROP2 and the PI3K/AKT pathway to the pyroptosis machinery inside the cell.

The research team began by screening for genes that are highly expressed in hypopharyngeal squamous cell carcinoma and identified TROP2 as a standout. When the investigators examined tumor and normal tissues, they found that TROP2 was significantly upregulated in the cancer, with the strongest signal localized to tumor epithelial cells. That distribution matters because epithelial cells are the compartment from which this carcinoma arises, suggesting the protein is not merely a bystander but a feature of the malignant cells themselves.

To test what TROP2 actually does, the researchers manipulated its levels in HPSCC cells, forcing the protein to be overexpressed in some experiments and knocking it down in others. They then measured how these changes affected the cells’ progression phenotypes and their susceptibility to pyroptosis. The results pointed in one direction: TROP2 promotes the cancer’s advance by suppressing pyroptosis, the lytic, inflammation-generating form of cell death that would otherwise eliminate damaged or infected cells.

The mechanistic detail goes deeper than a simple correlation. Using molecular biology techniques, the team showed that TROP2 regulates the NOD-like receptor, or NLR, signaling pathway, a branch of innate immunity that feeds into pyroptosis. In cells where TROP2 was active, key pyroptosis-related proteins were downregulated. The affected molecules included GSDMD-N, the cleaved fragment of gasdermin D that forms pores in the cell membrane and executes pyroptotic death; Cleaved Caspase-1 (p20), the activated form of the enzyme that triggers that cleavage; and the inflammatory signaling molecules IL18 and IL-1β, which are released when pyroptosis proceeds. Suppressing this cascade, the study indicates, removes a barrier that would otherwise restrain tumor progression.

A third layer of the pathway emerged when the investigators looked upstream of the pyroptosis proteins. Their analysis identified the PI3K/AKT signaling pathway as critically involved in TROP2-mediated inhibition of pyroptosis. PI3K/AKT is a well-known pro-survival cascade in cancer biology, and in this system it appears to act as the relay through which TROP2 exerts its anti-pyroptotic effect. In practical terms, the findings place TROP2 upstream of PI3K/AKT, which in turn restrains the NLR-driven cell-death program, leaving tumor cells intact and free to proliferate.

The study also addressed why TROP2 is overexpressed in the first place. Upstream analysis revealed that the transcription factor JUND directly binds to the TROP2 promoter, the stretch of DNA that controls the gene’s activity, and activates it. The researchers verified this interaction using chromatin immunoprecipitation, a technique that allows scientists to confirm which proteins are physically attached to specific genomic regions in living cells. That binding, the authors report, contributes to TROP2’s overexpression in HPSCC, completing a regulatory axis that begins with a transcription factor and ends with the suppression of a cell-death program.

The authors summarize the circuit as a JUND-TROP2-PI3K/AKT-pyroptosis axis and describe it as a potential therapeutic target for the treatment of hypopharyngeal squamous cell carcinoma. Because each node in the chain was tested in the study, the axis offers several points at which a future intervention could theoretically break the pathway, whether by blocking JUND’s grip on the TROP2 promoter, interfering with TROP2 itself, or modulating the PI3K/AKT signal that follows.

The work was conducted using established molecular approaches: expression profiling in tumor and normal tissues to establish where TROP2 accumulates, overexpression and knockdown experiments to establish what it does, protein-level assays to trace the pyroptosis and PI3K/AKT changes, and ChIP to confirm the JUND-promoter interaction. The findings are presented as preclinical laboratory results, and the paper notes that the study was designed to determine the underlying mechanism by which TROP2 regulates HPSCC rather than to evaluate any treatment in patients.

For a cancer characterized by an extremely poor prognosis, the identification of a single suppressible pathway is a notable result. The study’s conclusion frames the JUND-TROP2-PI3K/AKT-pyroptosis axis as a potential therapeutic target, and the detailed mapping of how TROP2 holds pyroptosis in check provides the mechanistic foundation that any such therapeutic exploration would need to build on.

Subject of Research: The role of TROP2 in suppressing pyroptosis via the PI3K/AKT pathway in hypopharyngeal squamous cell carcinoma

Article Title: TROP2 suppresses pyroptosis via the PI3K/AKT pathway to drive tumor progression in hypopharyngeal squamous cell carcinoma

Article References: Wu, L., Ma, W., Wu, W., Wang, K., Zhang, R., Zhang, X., Ying, Z., & Chen, T. (2026). TROP2 suppresses pyroptosis via the PI3K/AKT pathway to drive tumor progression in hypopharyngeal squamous cell carcinoma. Cancer Cell International. https://doi.org/10.1186/s12935-026-04495-w

Image Credits: AI Generated

DOI: 10.1186/s12935-026-04495-w

Keywords: TROP2, pyroptosis, PI3K/AKT pathway, hypopharyngeal squamous cell carcinoma, JUND, NLR signaling, GSDMD-N, Caspase-1, IL-1β, tumor progression, cancer cell death, transcriptional regulation