Project description:Transcriptional profiling of adult forestomach epithelium comparing K5-CreER controsl with K5-CreER;Rosa26Sox2/Sox2 mutants. Two doses of tamoxifen were given and four weeks later the epithelal sheets were harvested for RNA extraction. Goal was to determine the effects of Sox2 overexpression on epithelial phenotypic changes. Two-condition experiment, wildtype Vs Sox2 overexpression mutant. Biological replicates: 3 control replicates, 3 mutant replicates.
Project description:Transcriptional profiling of adult forestomach epithelium comparing K5-CreER controsl with K5-CreER;Rosa26Sox2/Sox2 mutants. Two doses of tamoxifen were given and four weeks later the epithelal sheets were harvested for RNA extraction. Goal was to determine the effects of Sox2 overexpression on epithelial phenotypic changes.
Project description:Gene expression was compared between wild type forestomach and hindstomach epithelial cells at embryonic day E14.5. Gene expression was compared between GATA4 knock out hindstomach epithelial cells and wild type hindstomach epithelial cells at embryonic day E14.5. Gene expression was compared between GATA4 knock in forestomach epithelial cells and wild type forestomach epithelial cells at embryonic day E14.5.
Project description:Cancer originates as the progressive accumulation of genetic mutations in proto-oncogenes and tumor suppressors. However, the early events underlying tumor initiation remain largely elusive, mostly due to the general lack of information regarding the cells-of-origin responsible for tumor formation as well as the precise impacts of genetic insults on tumor initiation in vivo. Here, we demonstrate that Sox2-positive (Sox2+) adult stem cells are responsible for epithelial squamous tumor formation. Conditional expression of oncogenic Kras (KrasG12D) and knockout of p53 (also known as Trp53) in Sox2+ cells quickly and specifically resulted in the formation of squamous tumors in the forestomach and esophagus. GFP-based lineage tracing experiments demonstrated that Sox2+ cells are the cells-of-origin of squamous tumors in the esophagus and forestomach. Of note, our data showed that p53 deletion alone did not suffice for tumor initiation. On the contrary, tumor initiation was observed upon KrasG12D activation whereas p53 deletion further contributed to the malignancy of the generated tumors, pointing out distinct roles for Kras activation and p53 deletion in squamous tumor formation and progression, to which a multihit carcinogenesis model can be applied. Global gene expression analysis revealed secreting factors upregulated in the generated tumors induced by oncogenic Kras, which contribute to tumor progression. Taken together, these results demonstrate that epithelial squamous tumors can specifically originate as a consequence of defined genetic mutations in a Sox2+ cell population and highlight the connections between proliferative stem cells and tumor development in vivo.
Project description:Purpose: to characterise the steady state gene expression and transcriptomic response of resident murine epidermal immune cells (dendritic epidermal T cells, DETC; Langerhans cells, LCs) and epithelial cells (interfollicualr keratinocytes) to non-microbial stress in the form of ultraviolet B (UVB) radiation Methods: 6 C57Bl/6 mice were administered 300mJ/cm^2 UVB radiation to the dorsal side of both ears 24hr prior to tissue harvest, and another 6 administered the same dose 4 hr prior. Ears were harvested and dorsal and ventral ear sheets were separated. Samples were pooled from 2 mice to generate 3 biological replicates per timepoint. Dorsal sheets were used for UV samples, while ventral sheets from 24hr UV mice were used as unchallenged skin. Epidermis was separated and digested, and epidermal populations were FACS sorted. Libraries were prepared and sequenced on an Illumina HiSeq 2500. Conclusions: these data reveal the transcriptomic response of LC, DETC and interfollicular keratinocytes to acute epithelial stress in the form of DNA damage
Project description:In order to understand the molecular mechanisms of changes seen in the adult mouse intestine in response to Sox2 overexpression, gene expression was analyzed in the ileum upon 2-day Doxycycline (DOX) treatment of mice containing Dox-inducible Sox2 transgene. Repression of Cdx2 and of its intestinal targets was observed and confirmed by Western blotting and immunostaining. This effect of Sox2 was distinct from the effect of overexpression of Oct4. 6-8 week old TetON-Sox2, rtTA controls (no TetOP-Sox2 transgene), TetON-Oct4, and TetON-Sox2 X TetON-Oct4 mice (2 replicates) were treated for 2 days with 2 mg/ml DOX or were left untreated. Intestines (ileum part) were collected and total mRNA was extracted.