Reply to the Letter to the Editor of Nicholas Wright

摘要

To the Editor-in-Chief,We would like to thank Prof. Wright for his constructive remarks on the online version of our paper: "Differential localization of LGR5 and Nanog in clusters of colon cancer stem cells" by Amsterdam et al. available online 23 October 2012.We have modified the paper in the final version of 2013 wherever we believed that the criticism was justified, but we have not modified the article in response to comments that we considered unjustified as follows: In Figs. 2 and 3 in the early (online) version we stated that it showed cancer tissue while the morphological appearance showed normal tissue. We now have corrected this in the revised text. However, since these images were taken from sections adjacent to the cancerous tissue and expressed the typical cancer stem cell (CSC) markers (Nanog and LGR5), we suggest that they represent a pre-malignant stage. To verify this point, we also analysed stained sections obtained from normal colon tissue and there was no staining of Nanog and only a very scattered labelling of LGR5. Moreover, since the main issue of the paper is the presence of the CSCs in human colon cancer, we append to this letter a micrograph (Fig. 1) expressing Nanog and LGR5 that clearly demonstrates the presence of Nanog and LGR5 in carcinomas of the colon. As for the claim that colon CSCs cannot exist in the colon stroma, the Muscularis propria or the nervous plexi, the literature clearly describes such situations. For example see references cited below by Xu et al. (2008), Shinagawa et al. (2010), Pinchuk et al. (2010), De Boech et al. (2013) and also those of Gil et al. (2010) and Leitig et al. (2009) (cited in our paper).