Fig. 1: Pum1/2^CKO suppresses the development of colorectal cancer.

a, c RT-qPCR examination of the relative Pum1 (a) or Pum2 (c) mRNA levels in human CRC specimens from 22 patients as compared to adjacent normal tissues. Actin was used as an internal control. b, d mRNA expression of Pum1 (b) or Pum2 (d) in human colorectal cancer clinical specimens at different stages using the TCGA mRNA HiSeq expression array data. Error bars represent SD. e Schematic overview of the CRC induction model. C57BL/6J mice (n = 8 for each group) were injected with tamoxifen every other day for 7 days to knock out Pum1/2 in intestinal epithelial cells. 16 days later, the mice were injected with azoxymethane (AOM), followed by three cycles of treatment with dextran sodium sulfate (DSS), as described in “Methods” section. f Representative images of colon and rectum in control (Pum1^flox/flox::Pum2^flox/flox) and Pum1/2^CKO (Lgr5^cre::Pum1^flox/flox::Pum2^flox/flox) mice after AOM/DSS treatment, depicting the extent of tumor burden. g The number and diameter of tumors in the entire colon and rectum were measured at the end of the study (n = 8). Error bars represent SD. h The length of control and Pum1/2^CKO colon after AOM/DSS treatment (n = 8). Error bars represent SD. i Body weight of Pum1/2^CKO and control mice in AOM/DSS model from day 0 to 60 normalized to body weight at day 0 was normalized to 100 (n = 8). Error bars represent SD. j Representative micrographs of immunohistochemistry staining for PUM1 and PUM2 in colon tissues containing tumors from control and Pum1/2^CKO mice after AOM/DSS treatment. k Representative micrographs of H&E staining of colon tumors in control and Pum1/2^CKO mice after AOM/DSS treatment. l, m Representative micrographs of immunochemistry staining for Ki-67 (l) and TUNEL (m) in tumors from control and Pum1/2^CKO mice after AOM/DSS treatment. Bar graph showing the numbers of Ki-67 (l, n = 2) and TUNEL (m, n = 3) positive tumor cells per high power fields (HPF) from control and Pum1/2^CKO mice after AOM/DSS treatment. Error bars represent SD. Source data are provided as a Source Data file.