Research Paper Volume 13, Issue 12 pp 16178—16197

GPR30-mediated HMGB1 upregulation in CAFs induces autophagy and tamoxifen resistance in ERα-positive breast cancer cells

Abnormally activated and increased GPR30 in TAM-resistant breast CAFs. (A) Representative cases of immunostaining of breast tumor tissue samples, (B) Quantitative GPR30 staining in primary tumor fibroblasts (PTFs) and metastatic fibroblasts (MTFs). (C) Breast cancer tissues and (D) paired immortalized cells evaluated by real time quantitative-PCR. GPR30 was detected in NFs and CAFs; each sample was normalized to its β-actin mRNA content. (*P t-test). (E) GPR30 protein content in paired cell lines. (F) GPR30 is activated by TAM and G1 in breast CAFs. Treatment with TAM (10 nM) and G1 (1 μM) for 15 min, with or without pretreatment with G15 (1 μM) in CAFs, and monitoring of Ca2+ labeled with the Fluo-3/AM probe by laser scanning spectral confocal microscopy. Scale bar: 25 mm (*P

Figure 1. Abnormally activated and increased GPR30 in TAM-resistant breast CAFs. (A) Representative cases of immunostaining of breast tumor tissue samples, (B) Quantitative GPR30 staining in primary tumor fibroblasts (PTFs) and metastatic fibroblasts (MTFs). (C) Breast cancer tissues and (D) paired immortalized cells evaluated by real time quantitative-PCR. GPR30 was detected in NFs and CAFs; each sample was normalized to its β-actin mRNA content. (*P < 0.05, CAFs vs NFs, Student's t-test). (E) GPR30 protein content in paired cell lines. (F) GPR30 is activated by TAM and G1 in breast CAFs. Treatment with TAM (10 nM) and G1 (1 μM) for 15 min, with or without pretreatment with G15 (1 μM) in CAFs, and monitoring of Ca2+ labeled with the Fluo-3/AM probe by laser scanning spectral confocal microscopy. Scale bar: 25 mm (*P < 0.05).