Fig. 5: GBPs activate HSF1 to stimulate MHC-I expression and tumor immunity.

a-c. A375 cells were forced expression of GBPs. MHC-I RNA (a), surface expression (b) or total protein (c) levels were determined 24 hours (a) or 48 hours (b, c) afterwards. P value by 2-sided t-test. 1 of 2 blots is shown.

d. MHC-I surface expression in YUMM1.7 or B16 cells upon Gbp2 overexpression. P value by 2-sided t-test.

e. HSF1 chromatin IP for indicated gene promoters were performed in IFNγ-pretreated A375 cells. P value by 2-sided t-test.

f. A375 cells were treated with 17-AAG to activate HSF1. Protein levels of HLA-ABC were determined 48 hours after treatment. 1 of 2 experiments is shown.

g. A375 HSE-luc cells were forced expression of GBPs. Luciferase activity were detected 48 hours afterwards. P value by 2-sided t-test.

h. A375 cells were forced expression of GBP1. Indicated proteins were determined 12 hours afterwards. 1 of 2 experiments is shown.

i. A375 WT or GBPs KO cells were treated with IFNγ. Indicated proteins were determined 24 hours afterwards. 1 of 2 experiments is shown.

j. A375 cells were forced expression of GBP1, and treated with KRIBB11. MHC-I surface expression was determined 48 hours afterwards. P value by 2-sided t-test.

k-l. MC38 shFluc, shGbp2, shHsf1, or shGbp2+shHsf1 cells were treated with IFNγ. Indicated proteins (k) or MHC-I surface expression (l) were determined 48 hours afterwards. 1 of 2 experiments is shown. P value by 2-sided t-test.

m. Tumor growth curves of MC38 shFluc, shGbp2, shHsf1, and shGbp2+shHsf1 cells in C57BL/6 mice. n = 5 animals, P value by 2-sided t-test for end point tumor volume.

n. Percentages of intral-tumoral IFNγ⁺CD8⁺ T cells or TNFα⁺CD8⁺ T cells in MC38 tumors carrying shFluc, shGbp2, shHsf1, or shGbp2+shHsf1. n = 5 biological independent samples, P value by 2-sided t-test.

All data are mean ± SD.

n = 3 biological independent samples in (a, b, d, e, g, j, l).

Source data are provided in Soure_data_Fig5.xlsx and Unmodified_blots_Fig5.pdf.