Journal: Cancer Discovery
Article Title: Oncogenic KRAS-Dependent Stromal Interleukin-33 Directs the Pancreatic Microenvironment to Promote Tumor Growth
doi: 10.1158/2159-8290.CD-24-0100
Figure Lengend Snippet: Tumor cell-initiated autocrine signaling drives IL33 upregulation in pancreatic fibroblasts. A, Ex vivo culture scheme for iKRAS G12D ; Trp53 R172H/+ (cell line 9805) CM generation and healthy pancreatic fibroblasts (cell line CD1WT). B, Western blot of CD1WT whole cell lysates after 24 hours of treatment with DMEM, iKRAS G12D “OFF” CM, iKRAS G12D “ON” CM, or concurrent iKRAS G12D “ON” CM and JAK1/2i. C, RT-qPCR of CD1WT after treatment with DMEM, JAK1/2i (4 hours, 0.3 μmol/L), iKRAS G12D “ON” CM (24 hours), or pretreatment of iKRAS G12D “ON” CM for 20 hours followed by spike-in of JAK1/2i (0.3 μmol/L) for an additional 4 hours (24 hours total iKRAS G12D “ON” CM treatment). Groups were compared with ordinary one-way ANOVA. D, Western blot of CD1WT whole cell lysates after 24 hours of treatment with DMEM, iKRAS G12D “ON” CM, rIL6 (left) or rLIF (right). E, Representative western blot of CD1WT whole cell lysates after treatment with DMEM, iKRAS G12D “OFF” CM, or iKRAS G12D “ON” CM for increasing intervals of time. Densitometry quantification for IL33 normalized to loading control (α-tubulin) and pSTAT3 normalized to total STAT3 are shown. Quantification is relative to the 0-hour timepoint. Ordinary one-way ANOVA was performed to compare each timepoint to the control. F, RT-qPCR of CD1WT after treatment with DMEM, iKRAS G12D “OFF” CM, or iKRAS G12D “ON” CM for increasing intervals of time. Values are log 10 transformed to better visualize large changes in gene expression level. Ordinary one-way ANOVA was performed to compare each timepoint to the 0-hour timepoint. Only comparisons with P value < 0.05 are shown. G, Experimental scheme to block autocrine signaling in CD1WT. CD1WT were treated with DMEM, iKRAS G12D “ON” CM, or rLIF for 18 hours, and then, the resulting CM was set aside. Cells were washed with PBS and then given back their original 18-hour CM or given GolgiStop (1.3 μL/2 mL) + fresh DMEM, iKRAS G12D “ON” CM, or rLIF media. Cells were incubated for an additional 6 hours before harvesting CD1WT RNA and protein. H, RT-qPCR of CD1WT after autocrine blocking experiment. Two-tailed Student t test was performed to compare groups of interest (all tested comparisons shown). I, Western blot of CD1WT whole cell lysates after autocrine blocking experiment. In all experiments with iKRAS G12D CM, doxycycline is used as a vehicle control. In all experiments with JAK1/2i (ruxolitinib), DMSO was used as a vehicle control. All replicates represent complete, independent experiments. RT-qPCR values are normalized to Ppia (Cyclophilin A) and relative to the untreated DMEM group. Histogram data are mean ± standard deviation.
Article Snippet: Primary antibodies were used at the following concentrations: mouse IL33 (1:100, #AF3625, R&D Systems), PDGFRα (1:500, #3164S, Cell Signaling), pSTAT3 (Y705; 1:1,000, #9145S, Cell Signaling), STAT3 (1:1,000, #9139S, Cell Signaling), p-SMAD2 (S465/467)/SMAD3 (S423/425; 1:500, #8828S, Cell Signaling), SMAD2/3 (1:1,000, #8685S, Cell Signaling), α-tubulin (1:2,000, #3873S, Cell Signaling), vinculin (1:2,000, #13901S, Cell Signaling).
Techniques: Ex Vivo, Western Blot, Quantitative RT-PCR, Control, Transformation Assay, Gene Expression, Blocking Assay, Incubation, Two Tailed Test, Standard Deviation