Cancer cells flood tumors with palmitate that exhausts CAR-T cells

Chimeric antigen receptor T cell therapy has transformed the treatment of several blood cancers, but solid tumors have proven far harder to defeat. A study published in Nature Cancer on 30 October 2026 points to one reason why: renal cancer cells can reshape the chemical environment around themselves in a way that drains attacking T cells of their energy. The work, led by Hongye Wang and Chuanjie Zhang with colleagues, identifies the epigenetic regulator BAZ2A as a driver of resistance to CD70-targeted CAR-T therapy and traces the effect to a single saturated fatty acid, palmitic acid, accumulating in the tumor microenvironment.

To find the resistance mechanism, the researchers ran an in vivo CRISPR screen in a mouse renal cell carcinoma model treated with anti-hCD70 CAR-T cells. The screen singled out BAZ2A, a chromatin-associated protein, as a key mediator of tumor-intrinsic resistance.

The mechanism that emerged is metabolic rather than immunological in the usual sense. According to the study, BAZ2A-driven epigenetic remodeling programs renal cancer cells to produce and release palmitic acid, a saturated fatty acid, so that it accumulates in the tumor microenvironment. Figure descriptions in the article indicate that BAZ2A works together with the transcription factor Pax8 on super-enhancers governing the fatty acid synthesis gene FASN, strengthening palmitic acid metabolism in the tumor cells.

The fatty acid does not stay outside the T cells. The researchers report that excess palmitic acid is taken up by the CAR-T cells infiltrating the tumor, and that this uptake impairs their mitochondrial fitness. The study links the damage to PGC-1α, a master regulator of mitochondrial biogenesis and energy metabolism: palmitate inhibits PGC-1α activity, and the T cells are thereby pushed into a dysfunctional state.

The molecular detail goes one step further. The article’s figure summaries describe PGC-1α palmitoylation, the chemical attachment of the fatty acid to the PGC-1α protein, as an event that induces epigenetic dysregulation in CD70 CAR-T cells.

Importantly, the resistance is not presented as irreversible. Pharmacologic inhibition of BAZ2A reduced lipid accumulation and restored CAR-T cell activity in vivo, the study reports. A figure summary further indicates that the BAZ2A inhibitor GSK2801 sensitized both renal cell carcinoma and colorectal cancer models to CAR-T therapy, hinting that the mechanism may extend beyond kidney cancer, at least in preclinical models.

The findings frame tumor lipid remodeling as a therapeutic target in its own right. The authors suggest that blocking the production or accumulation of palmitate in the tumor microenvironment could overcome CAR-T resistance in solid tumors.

As with any preclinical study, the results come from mouse models and cell-based experiments, and clinical translation will require testing in patients. The abstract notes that tumor-intrinsic resistance mechanisms in solid tumors remain poorly defined, which is precisely the gap this work addresses. Still, the study delivers a coherent biological story: an epigenetic regulator in cancer cells, a saturated fatty acid as the exported weapon, a palmitoylated metabolic regulator in T cells as the target, and a pharmacologic inhibitor that reverses the process in living models.

Subject of Research: Epigenetic regulation of tumor lipid metabolism as a mechanism of CAR-T cell resistance in renal cell carcinoma

Article Title: BAZ2A-induced epigenetic states in cancer cells fuel palmitate accumulation in the tumor microenvironment driving CAR-T cell exhaustion

Article References: Wang, H., Geng, H., Zhao, J., Ge, H., Shen, Y., Wu, Z., Bian, L., Zuo, J., Sun, Z., Yang, Y., Zhu, J., Shen, W., Zheng, J., Cui, D., Ding, J., Yang, S., He, H., Huang, H., Gao, Y., … Zhang, C. (2026). BAZ2A-induced epigenetic states in cancer cells fuel palmitate accumulation in the tumor microenvironment driving CAR-T cell exhaustion. Nature Cancer. https://doi.org/10.1038/s43018-026-01267-3

Image Credits: AI Generated

DOI: 10.1038/s43018-026-01267-3

Keywords: BAZ2A, CAR-T cell therapy, palmitic acid, renal cell carcinoma, tumor microenvironment, PGC-1α palmitoylation, epigenetic regulation, FASN, immune resistance, GSK2801, solid tumors, T cell exhaustion