Deciphering cellular processes responding to lethality of 17β-estradiol by quantitative phosphoproteomics

Paradoxically, despite the physiological actions of endogenous E2 (0.2-1.0 nmol/L), numerous clinical and experimental studies demonstrated that high-dose E2 treatment could cause tumor regression and exert pro-apoptotic actions in multiple cells, but the underlying mechanism is still undescribed.

Especially, little information of cellular processes responding to lethality of 17β-estradiol is available. In the present work, we attempted to characterize the cellular processes responding to high-dose (mmol/L) E2 treatment by quantitative phosphoproteomics to help understand the regulatory mechanism of E2 induced cell death. To investigate the intracellular cellular processes responding to high-dose (umol/L) E2 treatment, solid phase extraction (SPE)-based immobilized titanium ion affinity chromatography (Ti4+-IMAC) phosphopeptide enrichment method coupled with data independent acquisition (DIA)-based quantitative proteomics was employed for in-depth screening of high-dose E2 regulated phosphorylation sites.