Fig. 6
From: Targeting SPINK1 in the damaged tumour microenvironment alleviates therapeutic resistance
Therapeutically targeting SPINK1 promotes tumour responses to anticancer agents. a Experimental workflow for severe combined immunodeficient (SCID) mice. Two weeks after subcutaneous implantation and in vivo uptake of tissue recombinants, animals received single or combinational agents administered as metronomic treatments composed of several cycles. b Statistics of tumour end volumes. PC3 cells were xenografted alone or together with PSC27 subline cells to the hind flank of SCID mice. MIT was administered to induce tumour regression. c Transcript assessment of several canonical SASP factors expressed in stromal cells isolated from the tumours of SCID mice. Tissues from animals implanted with both stromal and cancer cells were subject to LCM isolation and subsequent assays. d Representative IHC images of SPINK1 expression in tissues isolated from placebo or MIT-treated animals. Square regions in the upper images were zoomed into lower images. Scale bars, 100 μm. e Statistical comparison of tumour end volumes in animals that underwent several different treatment modalities. Tumour volumes were measured at the end of an 8-week preclinical regimen. f Representative bioluminescence images (BLI) of PC3/PSC27 tumour-bearing animals in the preclinical trial. Digital signals were proportional to in vivo luciferase activities measured by an IVIS device. g Statistical assessment of DNA-damaged and apoptotic cells in the biospecimens analyzed in (e). Values are presented as a percentage of cells positively stained by IHC with antibodies against γ-H2AX or caspase 3 (cleaved). Right, representative IHC images of caspase 3 (cleaved). Biopsies of placebo-treated animals served as negative controls for MIT-treated mice. Scale bars, 100 μm. h SPINK1 concentration assessment in circulating blood of experimental mice treated by chemotherapy and/or SPINK1 mAb. Data were derived from human SPINK1-specific ELISA assays. Data are mean ± SD and representative of 3 independent experiments. P values were calculated by Student’s t-test (b, c, e, g, h) (^P > 0.05; *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001)
