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Zhigang Zhao

Publications and source records attributed to Zhigang Zhao.

3 recordsLinked to original sources

Super enhancer-driven transcriptional reprogramming promotes abiraterone resistance via neuroendocrine transition and ferroptosis evasion in castration-resistant prostate cancer.

Abiraterone resistance represents a major clinical challenge in the management of castration-resistant prostate cancer (CRPC), yet the epigenetic mechanisms that sustain this resistance remain poorly understood. In particular, how super enhancers (SEs) reprogram transcriptional networks to promote this therapy resistance has not been fully elucidated. Here, by integrating chromatin immunoprecipitation sequencing and transcriptome profiling, we identified aberrantly activated oncogenic SEs that drive the transcriptional upregulation of the transcription factors ELF3 and JUNB in abiraterone-resistance CRPC cells. Importantly, SE-driven activation of the ELF3/JUNB axis promotes abiraterone resistance by inducing WNT11-mediated neuroendocrine transition. In parallel, this transdifferentiated state is closely associated with ferroptosis resistance, as evidenced by the upregulation of key ferroptosis-protective genes, including FTH1 and GPX4. In contrast, disruption of the ELF3/JUNB-WNT11 axis markedly restored abiraterone sensitivity and triggered ferroptotic cell death in CRPC cells both in vitro and in vivo. Collectively, our findings highlight targeting SE-driven transcriptional programs as a promising strategy for overcoming abiraterone resistance in CRPC.

Male

Anoikis classification of lung squamous cell carcinoma reveals correlation with clinical prognosis and immune characteristics.

BACKGROUND: Anoikis is a new mode of cell death that has been shown to correlate significantly with tumors. However, the clinical prognostic significance of anoikis in lung squamous cell carcinoma (LUSC) remains poorly studied. METHODS: The differentially expressed ARGs and candidate genes were selected by the differential analysis to construct a predictive model. Independent prognostic gene was determined by Cox and LASSO analysis and we used the HCC95 and NCI H520 cell line to verify the gene function. We used the data from TCGA, GEO, GeneCards, and Harmonizome databases to analyze the immune microenvironment, functional enrichment, and drug sensitivity analysis. RESULTS: We identified 717 differentially expressed and selected 3 ARGs (FADD, SNAI1, and BAG4) to construct a predictive model. We found that SNAI1 is an independent prognostic gene and confirmed that knocking out the SNAI1 inhibited the HCC95/NCI H520 cell proliferation. We used single-sample gene-set enrichment analysis (ssGSEA) to evaluate the immune infiltration based on the 3 ARG expression levels. We constructed a risk score and provided a visual representation of the prophetic implications of the ARGs-based signature through a nomogram. We found 15 susceptible drugs in the high-risk group and 15 sensitive drugs in the low-risk group by the drug sensitivity analysis. CONCLUSION: We used ARGs to construct a prognosis model for LUSC that can accurately predict the prognosis of LUSC patients. ARGs, especially SNAI1, play an essential role in developing LUSC. These findings could provide individualized treatment plans and new research ideas for LUSC patients.

Humans

SpRY-mediated screens facilitate functional dissection of non-coding sequences at single-base resolution.

CRISPR mutagenesis screens conducted with SpCas9 and other nucleases have identified certain cis-regulatory elements and genetic variants but at a limited resolution due to the absence of protospacer adjacent motif (PAM) sequences. Here, leveraging the broad targeting scope of the near-PAMless SpRY variant, we have demonstrated that saturated SpRY mutagenesis and base editing screens can faithfully identify functional regulatory elements and essential genetic variants for target gene expression at single-base resolution. We further extended this methodology to investigate a genome-wide association study (GWAS) locus at 10q22.1 associated with a red blood cell trait, where we identified potential enhancers regulating HK1 gene expression, despite not all of these enhancers exhibiting typical chromatin signatures. More importantly, our saturated base editing screens pinpoint multiple causal variants within this locus that would otherwise be missed by Bayesian statistical fine-mapping. Our approach is generally applicable to functional interrogation of all non-coding genomic elements while complementing other high-coverage CRISPR screens.

Humans