PYGB targeted by androgen receptor contributes to tumor progression and metabolic reprogramming in esophageal squamous carcinoma.

Background: The incidence and mortality rates of esophageal squamous cell carcinoma (ESCC) are conspicuously augmented in men in contrast to women. The androgen receptor (AR), prevalently associated with the manifestation of male characteristics, is regarded as a pivotal determinant in tumor progression. Nevertheless, its exact role in ESCC remains insufficiently delineated.

Methods: In this study, we probed the expression levels of AR and glucose metabolism enzymes in ESCC tissues by means of immunohistochemistry. We exploited chromatin immunoprecipitation and dual luciferase reporter assays to delve into the transcriptional regulatory interrelationships between AR and these enzymes. A gamut of molecular techniques-including multi-omics sequencing, colony formation assays, cell counting kit 8 (CCK8), 5-Ethynyl-2'-deoxyuridine (EdU) incorporation assays, wound-healing assays, transwell migration assays, extracellular acidification rate (ECAR) measurements, lipid droplet fluorescence imaging, and xenograft models-were enlisted to illuminate the functions of these enzymes within ESCC cells.

Results: Our discoveries manifested that AR expression was strikingly higher in male ESCC tissues than in their female counterparts. Significantly, we discerned that glycogen phosphorylase B (PYGB), a cardinal enzyme implicated in glucose metabolism, demonstrated not only a positive correlation with AR expression but also an association with adverse prognostic outcomes for ESCC patients. Moreover, AR directly binds to the promoter region of the PYGB gene, thereby potentiating its transcriptional activity. This upregulation of PYGB was ascertained to facilitate proliferation, invasion, and metastasis among ESCC cells while intensifying glycolysis and modifying lipid metabolism pathways within these cells. In animal models employing nude mice, elevated PYGB levels were witnessed to expedite subcutaneous tumor growth as well as lung metastasis.

Conclusions: Collectively, our study establishes PYGB as a direct target of AR that assumes an indispensable role in both tumor progression and metabolic reprogramming affiliated with ESCC, thus paving novel avenues for therapeutic strategies centered on metabolic intercessions.