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Oral squamous cell carcinoma (OSCC) stands as a prevalent subtype of head and neck squamous cell carcinoma, leading to disease recurrence and low survival rates. PPARγ, a ligand-dependent nuclear transcription factor, holds significance in tumor development. However, the role of PPARγ in the development of OSCC has not been fully elucidated. Through transcriptome sequencing analysis, we discovered a notable enrichment of ferroptosis-related molecules upon treatment with PPARγ antagonist. We subsequently confirmed the occurrence of ferroptosis through transmission electron microscopy, iron detection, etc. Notably, ferroptosis inhibitors could not completely rescue the cell death caused by PPARγ inhibitors, and the rescue effect was the greatest when disulfidptosis and ferroptosis inhibitors coexisted. We confirmed that the disulfidptosis phenotype indeed existed. Mechanistically, through qPCR and Western blotting, we observed that the inhibition of PPARγ resulted in the upregulation of heme oxygenase 1 (HMOX1), thereby promoting ferroptosis, while solute carrier family 7 member 11 (SLC7A11) was also upregulated to promote disulfidptosis in OSCC. Finally, a flow cytometry analysis of flight and multiplex immunohistochemical staining was used to characterize the immune status of PPARγ antagonist-treated OSCC tissues in a mouse tongue orthotopic transplantation tumor model, and the results showed that the inhibition of PPARγ led to ferroptosis and disulfidptosis, promoted the aggregation of cDCs and CD8+ T cells, and inhibited the progression of OSCC. Overall, our findings reveal that PPARγ plays a key role in regulating cell death in OSCC and that targeting PPARγ may be a potential therapeutic approach for OSCC. [ABSTRACT FROM AUTHOR]

Lesion mimic mutants (LMMs) are ideal materials for studying cell death and resistance mechanisms. Here, we identified and mapped a novel rice LMM, g380. The g380 exhibits a spontaneous hypersensitive response-like cell death phenotype accompanied by excessive accumulation of reactive oxygen species (ROS) and upregulated expression of pathogenesis-related genes, as well as enhanced resistance to Xanthomonas oryzae pv. oryzae (Xoo). Using a map-based cloning strategy, a 184,916 bp deletion on chromosome 2 that overlaps with the diterpenoid biosynthetic gene cluster was identified in g380. Accordingly, the content of diterpenoids decreased in g380. In addition, lignin, one of the physical lines of plant defense, was increased in g380. RNA-seq analysis showed 590 significantly differentially expressed genes (DEG) between the wild-type 9311 and g380, 585 of which were upregulated in g380. Upregulated genes in g380 were mainly enriched in the monolignol biosynthesis branches of the phenylpropanoid biosynthesis pathway, the plant–pathogen interaction pathway and the phytoalexin-specialized diterpenoid biosynthesis pathway. Taken together, our results indicate that the diterpenoid biosynthetic gene cluster on chromosome 2 is involved in immune reprogramming, which in turn regulates cell death in rice. [ABSTRACT FROM AUTHOR]