Fig. 5: TMPyP4 induces DNA damage in a G4-dependent manner and activates the cGAS-STING pathway.

a, b GSEA of the signaling pathway, including regulation of double-strand break repair and DNA double-strand break response in MC38 tumors with TMPyP4 treatment or vehicle control treatment. c Mean tail moment of the HCT116 and MC38 cells treated with or without TMPyP4 in a comet assay. d Quantification of foci/nucleus of γ-H2AX immunofluorescence staining of HCT116 and MC38 cells treated with or without TMPyP4. e Statistical analysis of γ-H2AX in MC38 tumors with TMPyP4 treatment or vehicle control treatment. f Representative images of G4 and γ-H2AX immunofluorescence staining of HCT116 treated with plasmids pCDNA3.1 or PIF1-pCDNA3.1 in the presence of TMPyP4. g, h Quantification of foci/nucleus of G4 and γ-H2AX in (f). i, j Western blots of p-TBK1, TBK1, p-STING, STING, and GAPDH in colorectal cancer cells with the indicated concentrations of TMPyP4. k–m RNA levels of Ccl5, Cxcl10, and Ifn-β were detected in CT26 and MC38 treated with or without TMPyP4 for 48 h. n Representative immunostainings of CD8, CD11c, and P-STING in paraffin sections of MC38 tumors with TMPyP4 treatment or vehicle control treatment (CD8 [green], CD11c [orange], P-STING [red], DAPI [blue]) (magnification ×200). o, p The tumor size and tumor weight of C57BL/6 mice bearing indicated MC38 colon cancer treated with vehicle or 30 mg/kg TMPyP4. n = 5 mice for both groups. Values are represented as mean ± SD, ns: not significant, ^**p ≤ 0.01, ^***p ≤ 0.001, ^****p ≤ 0.0001, by untailed t-tests (c, d, e, g, h, k, l, m), or by two-way ANOVA (g).