Recent genetic studies in mice have established a key role for the nuclear receptor coregulator Trim24 in liver tumor suppression and provided evidence that Trim24 suppresses hepatocarcinogenesis by inhibiting retinoic acid receptor alpha (Rara)-dependent transcription and cell proliferation. However, it is unknown which downstream targets of Rara regulated by Trim24 are critical for tumorigenesis. We report here that loss of Trim24 results in the overexpression of interferon (IFN)/STAT pathway genes in the liver, a process that occurs early in tumorigenesis and is more pronounced in tumors, despite the enhanced expression, late in the disease, of negative regulators such as Usp18, Socs1 and Socs2.
Tripartite motif 24 (Trim24/Tif1α) tumor suppressor protein is a novel negative regulator of interferon (IFN)/signal transducers and activators of transcription (STAT) signaling pathway acting through retinoic acid receptor α (Rarα) inhibition.
Specimen part
View SamplesLung cancer remains the leading cause of cancer death. Genome sequencing of lung tumors from patients with Squamous Cell Carcinoma has identified SMAD4 to be frequently mutated. Here we used a novel mouse model to determine the molecular mechanisms regulated by loss of Smad4 which lead to lung cancer progression. Mice with ablation of Pten and Smad4 in airway epithelium developed metastatic adenosquamous tumors. Comparative transcriptomic and in vivo cistromic analyses determined that loss of PTEN and SMAD4 resulted in activation of the ELF3 and the ErbB2 pathway due to decreased ERRFI1s expression, a negative regulator of ERBB2 in mice and human cells. The combinatorial inhibition of ErbB2 and Akt signaling attenuated tumor progression and cell invasion, respectively. Expression profiles analysis of human lung tumors substantiated the importance of the ErbB2/Akt/ELF3 signaling pathway as both prognostic biomarkers and therapeutic drug targets for treating lung cancer.
ErbB2 Pathway Activation upon Smad4 Loss Promotes Lung Tumor Growth and Metastasis.
Age, Specimen part
View SamplesLung cancer is the leading cause of cancer related death in both men and women in the United States. Recently, Smad4 was discovered to be common somatic alteration in human squamous cell lung cancer. Our goal was to delineate the role of Smad4 in lung cancer. We have shown for the first time that the ablation of Pten and Smad4 in the murine airway epithelium harbors a metastatic proximal adeno-squamous lung cancer.
ErbB2 Pathway Activation upon Smad4 Loss Promotes Lung Tumor Growth and Metastasis.
Specimen part, Disease, Disease stage
View SamplesThe gene expression of bone marrow cells of mice enriched for
Gremlin 1 identifies a skeletal stem cell with bone, cartilage, and reticular stromal potential.
Sex, Specimen part
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