Project description:The murine basal-like mammary carcinoma cell line H8N8 was transplanted into syngeneic WAP-T mice and growing tumors were subjected to a single dose of combination chemotherapy (100 mg/kg body weight cyclophosphamide, 5 mg/kg BW doxorubicin and 100 mg/kg BW 5-FU, short CAF). Mice of the control group were treated with one injection vehicle solution. Three cohorts of animals were generated: control, remission, and regrowth group. Tumor cells were isolated from lesions of each group, purified by flow cytometry to remove non-tumor cells and debris, and finally subjected to whole transcriptome analysis by mRNA-sequencing.
Project description:WAP-Cre:Ptenf/f:p53lox.stop.lox_R270H composite mice were generated by genetic crossing. In these mice, Pten is deleted and a R270H p53 mutation in the DNA binding domain is induced upon expression of Cre recombinase in pregnancy-identified alveolar progenitors. Tumors were characterized by histology, marker analysis, various bioinformatics methods, high-throughput (HTP) FDA-drug screen as well as orthotopic injection to quantify tumor initiating cells (TICs) and tail-vein injection to identify lung-metastasis. Expression data comparing 2 types of Pten-deficient tumors (spindle and poorly differentiated) with other modles of mouse mammary tumors 2 types of Pten deletion plus p53-R270H mutation tumors (spindle and poorly differentiated) was compared with MMTV-Neu, Spindle Pten-p53-deficient tumors, and wild-type mammary gland cells.
Project description:To model the effect of Pten loss on breast cancer, we deleted Pten using a floxed allele and the deleter lines MMTV-Cre(NLST), which targets stem/bi-potent progenitor cells, and WAP-Cre, which targets CD24-positive, pregnancy-identified stem cells/alveolar progenitors. Mammary tumors were detected in WAP-Cre:Ptenf/f females with a latency of 15.2 months. By 18 months, nearly all mice had succumbed to cancer. MMTV-Cre:Ptenf/f mice developed mammary tumors after a longer latency of 26.4 months and reduced penetrance (70%) compared to WAP-Cre:Ptenf/f mice. Tumors from both models were heterogeneous, consisting primarily of differentiated adenocarcinoma (adenomyoepithelioma; ~70%) and adenosquamous carcinoma (20-25%). In addition, a small fraction of tumors was classified as acinar and poorly differentiated adenocarcinoma (4-7%) and adenosarcoma (3-4%). To test the consequences of combined Pten and p53 gene mutation on breast cancer, we deleted both genes via MMTV-Cre or WAP-Cre. Kaplan-Meier tumor free survival curves revealed that WAP-Cre:Ptenf/f:p53f/f and MMTV-Cre:Ptenf/f:p53f/f females developed tumors with reduced latency of 11.3 and 9.8 months, compared with 15.2, 26.4, and 16.9 months for single-mutant WAP-Cre:Ptenf/f, MMTV-Cre:Ptenf/f or MMTV-Cre:p53f/f mice, respectively. In contrast to the heterogeneity of Pten tumors and small percentage of adenosarcomas in these mice, ~70% of Pten:p53 lesions were histologically classified as adeno-sacrcomatoid-like or mesenchymal-like breast cancer, with the rest exhibiting mixed mesenchymal plus adenocarcinomas and differentiated adenocarcinomas. The adeno-sacrcomatoid-like tumors expressed the mesenchymal markers vimentin, K5, SMA, N-cadherin and desmin but not ER, as well as islands of luminal-like K18 expressing cells surrounded by a layer of K14-positive cells. We used microarrays to detect differentially expressed genes in the Pten:p53 double-knock-out vs Pten or p53 single deletions Total RNA was extracted from tumors developed by double Trizol method and hybridized on Affymetrix microarrays.
Project description:Murine healthy tissue samples, DCIS and invasive mammary tumors were analyzed in order to identify marker genes which show enhanced expresssion in DCIS and invasive ductal carcinomas. Using this approach, we were able to identify a set of genes which might allow a better detection of DCIS and invasive carcinomas in the future. Samples consists of: 5 wild type breast tissue samples 5 healthy breast tissue sapmles of WAP-TNP8 mice 5 samples of mice one month, 5 samples of mice two month, 5 samples of mice three month, 5 samples of mice four month, and 5 samples of mice five month after activation of the SV40 oncogene 5 invasive tumors
Project description:Super-enhancers comprise of dense transcription factor platforms highly enriched for active chromatin marks. A paucity of functional data led us to investigate their role in the mammary gland, an organ characterized by exceptional gene regulatory dynamics during pregnancy. ChIP-Seq for the master regulator STAT5, the glucocorticoid receptor, H3K27ac and MED1, identified 440 mammary-specific super-enhancers, half of which were associated with genes activated during pregnancy. We interrogated the Wap super-enhancer, generating mice carrying mutations in STAT5 binding sites within its three constituent enhancers. Individually, only the most distal site displayed significant enhancer activity. However, combinatorial mutations showed that the 1,000-fold gene induction relied on all enhancers. Disabling the binding sites of STAT5, NFIB and ELF5 in the proximal enhancer incapacitated the entire super-enhancer, suggesting an enhancer hierarchy. The identification of mammary-specific super-enhancers and the mechanistic exploration of the Wap locus provide insight into the complexity of cell-specific and hormone-regulated genes. ChIP-Seq for STAT5A, GR, H3K27ac, MED1, NFIB, ELF5, RNA Pol II, and H3K4me3 in wild type (WT) mammary tissues at day one of lactation (L1), and ChIP-Seq for STAT5A, GR, H3K27ac, MED1, NFIB, ELF5, and H3K4me3 in WT mammary tissues at day 13 of pregnancy (p13). ChIP-Seq for STAT5A, GR, H3K27a in Wap-delE1a, -delE1b, -delE1c, -delE2 and -delE3 mutant mammary tissues at L1, and ChIP-Seq for NFIB and ELF5 in Wap-delE1b and -delE1c mutant mammary tissues at L1. ChIP-Seq for H3K4me3 in mammary-epthelial cells at p13 and L1. DNase-seq in WT mammary tissues at L1 and DNase-seq in Wap-delE1a, -delE1c, and -delE3 mutant mammary tissues at L1.
Project description:Miz1deltaPOZ mothers feature a lactation defect. In order to identify genes potentially regulated by Miz1 which could explain the observed phenotype and to assess the relative expression of milk protein genes and JAK-STAT pathway components, a genome-wide cDNA microarray was performed using samples from control and Miz1deltaPOZ animals obtained at day 6 of lactation (n=4 for each genotype).
Project description:Tumor targeted therapies have been largely inefficient due to lack of concomitant effects on the tumor microenvironment (TME). We investigated the MAtrix REgulating MOtif (MAREMO) mimicking peptide MP5, that inhibits the pro-tumorigenic extracellular matrix (ECM) molecule tenascin-C, using immunocompetent autologous breast cancer bearing mice. MP5 treatment led to tumor regression and reduced tumor cell dissemination. Several cancer hallmarks were abolished such as tumor cell promoting growth suppression and inhibition of plasticity enhancing responsiveness to death inducers. MP5 acts on other TME players leading to blood vessel normalization and depletion of fibroblasts diminishing the ECM as an orchestrator of immune suppression, causing immune cell infiltration and reactivation of anti-tumor immunity involving IFNgamma. Thus, targeting the tumor matrix using MAREMO in tenascin-C represents a powerful novel anti-cancer strategy.
Project description:Breast cancer (BC), the most frequent tumor entity in women globally, shows a high therapeutic response in early and non-metastatic stages. However, triple-negative BC (TNBC), enriched with cancer stem cells (CSCs), presents significant challenges due to its chemoresistant and metastatic nature. Ubiquitin Specific Proteinase 22 (USP22) has emerged as a key player in promoting CSC functions, contributing to resistance to conventional therapies, tumor relapse, metastasis, and poor survival across various cancers, including BC. The specific role of USP22 in TNBC, however, remains underexplored. In this study, we employed the MMTV-cre, Usp22fl/fl transgenic mouse model to investigate USP22's influence on stem cell-like properties in mammary tissue. High-throughput transcriptomic analyses, combined with publicly available patient data and TNBC culture models, were utilized to elucidate USP22's role in CSC characteristics of TNBC. Our findings reveal that USP22 enhances CSC properties and drug tolerance by supporting oxidative phosphorylation, a key factor in the poor response to conventional therapies in aggressive BC subtypes. The study uncovers a novel tumor-supportive role of USP22 in sustaining cellular respiration, which contributes to the drug-tolerant behavior of HER2+-BC and TNBC cells. This highlights USP22 as a potential therapeutic target, offering new avenues to optimize standard treatments and address the aggressiveness of these malignancies.
Project description:Cervical cancer (CC) remains a major cause of cancer-related mortality, particularly in regions with limited screening access, despite being highly preventable and treatable when detected early. MSX1, a homeobox transcription factor with dual roles as a tumor suppressor and oncogene, has an unclear role in CC pathogenesis. This study reveals that MSX1 acts as a tumor-promoting factor in CC, with de novo expression observed in precancerous lesions but absent in normal cervical epithelium. MSX1 enhances clonogenicity and migrationin cervical cancer cells, driven by epithelial-to-mesenchymal transition (EMT) induction. Mechanistically, MSX1 activates RHO/RAC/CDC42 cytoskeletal signaling pathways, with FOS—a downstream RHO effector—identified as a key mediator of CC aggressiveness. Targeting RHO signaling or FOS reverses MSX1-driven aggressive phenotypes, while proteasomal degradation of MSX1 reduces chemoresistance. These findings highlight MSX1’s critical role in CC progression and suggest its potential as a therapeutic target. The study underscores MSX1’s involvement in key oncogenic pathways, offering new insights for developing targeted therapies in cervical cancer.
Project description:WT mammary gland(WTMG),mutant-MG(MTMG),WT breast tumors(WTBT),MTBT and MTBT-adjacent MG were collected to do data-independent acquisiton(DIA)mass to find the intrinsic factors that is associated with Brca1-deficiency induced breast cancer.