Translation initiation factor eIF4E is overexpressed early in breast cancers in association with disease progression and reduced survival. Much remains to be understood regarding the role of eIF4E in human cancer. Using immortalized human breast epithelial cells, we report that elevated expression of elF4E translationally activates the TGF pathway, promoting cell invasion, loss of cell polarity, increased cell survival and other hallmarks of early neoplasia. Overexpression of eIF4E is shown to facilitate selective translation of integrin 1 mRNA, which drives the translationally controlled assembly of a TGF receptor signaling complex containing 31 integrins, -catenin, TGF receptor I, E-cadherin and phosphorylated Smads2/3. This receptor complex acutely sensitizes non-malignant breast epithelial cells to activation by typically sub-stimulatory levels of activated TGF. TGF can promote cellular differentiation or invasion and transformation. As a translational coactivator of TGF, eIF4E confers selective mRNA translation, reprogramming non-malignant cells to an invasive phenotype by reducing the set-point for stimulation by activated TGF. Overexpression of eIF4E may be a pro-invasive facilitator of TGF activity.
Eukaryotic Translation Initiation Factor 4E Is a Feed-Forward Translational Coactivator of Transforming Growth Factor β Early Protransforming Events in Breast Epithelial Cells.
Sex, Specimen part, Cell line
View SamplesWe developed a mouse model that captures radiation effects on host biology by transplanting unirradiated Trp53 null mammary tissue to sham or irradiated hosts. Gene expression profiles of tumors that arose in irradiated mice are distinct from those that arose in nave hosts.
Murine microenvironment metaprofiles associate with human cancer etiology and intrinsic subtypes.
Specimen part
View SamplesDensely ionizing radiation is a major component of the space radiation environment and has potentially greater carcinogenic effect compared to sparsely ionizing radiation that is prevalent in the terrestrial environment. It is unknown to what extent the irradiated microenvironment contributes to the differential carcinogenic potential of densely ionizing radiation. To address this gap, 10-week old BALB/c mice were irradiated with 100 cGy sparsely ionizing g-radiation or 10, 30, or 80 cGy of densely ionizing, 350 MeV/amu Si particles and transplanted 3 days later with syngeneic Trp53 null mammary fragments. Tumor appearance was monitored for 600 days. Tumors arising in Si-particle irradiated mice had a shorter median time to appearance, grew faster and were more likely to metastasize. Most tumors arising in sham-irradiated mice were ER-positive, pseudo-glandular and contained both basal keratin 14 and luminal keratin 8/18 cells (designated K14/18), while most tumors arising in irradiated hosts were K8/18 positive (designated K18) and ER negative. Comparison of K18 vs K14/18 tumor expression profiles showed that genes increased in K18 tumors were associated with ERBB2 and KRAS while decreased genes overlapped with those down regulated in metastasis and by loss of E-cadherin. Consistent with this, K18 tumors grew faster than K14/18 tumors and more mice with K18 tumors developed lung metastases compared to mice with K14/18 tumors. However, K18 tumors arising in Si-particle irradiated mice grew even faster and were more metastatic compared to control mice. A K18 Si-irradiated host profile was enriched in genes involved in mammary stem cells, stroma, and Notch signaling. Thus systemic responses to densely ionizing radiation enriches for a ER-negative, K18-positive tumor, whose biology is more aggressive compared to similar tumors arising in non-irradiated hosts.
Densely ionizing radiation acts via the microenvironment to promote aggressive Trp53-null mammary carcinomas.
No sample metadata fields
View SamplesTransforming growth factor beta-1 (TGFbeta) is a tumor suppressor during the initial stage of tumorigenesis, but it can switch to a tumor promoter during neoplastic progression. Ionizing radiation (IR), both a carcinogen and a therapeutic agent, induces TGFbeta activation in vivo. We now show that IR sensitizes human mammary epithelial cells (HMEC) to undergo TGFbeta-mediated epithelial to mesenchymal transition (EMT). Non-malignant HMEC (MCF10A, HMT3522 S1 and 184v) were irradiated with 2 Gy shortly after attachment in monolayer culture, or treated with a low concentration of TGFbeta (0.4 ng/ml), or double-treated. All double-treated (IR+TGFbeta) HMEC underwent a morphological shift from cuboidal to spindle-shaped. This phenotype was accompanied by decreased expression of epithelial markers E-cadherin, beta-catenin and ZO-1, remodeling of the actin cytoskeleton, and increased expression of mesenchymal markers N-cadherin, fibronectin and vimentin. Furthermore, double-treatment increased cell motility, promoted invasion and disrupted acinar morphogenesis of cells subsequently plated in Matrigel. Neither radiation nor TGFbeta alone elicited EMT, even though IR increased chronic TGFbeta signaling and activity. Gene expression profiling revealed that double treated cells exhibit a specific 10-gene signature associated with Erk/MAPK signaling. We hypothesized that IR-induced MAPK activation primes non-malignant HMEC to undergo TGFbeta-mediated EMT. Consistent with this, Erk phosphorylation were transiently induced by irradiation, persisted in irradiated cells treated with TGFbeta, and treatment with U0126, a Mek inhibitor, blocked the EMT phenotype. Together, these data demonstrate that the interactions between radiation-induced signaling pathways elicit heritable phenotypes that could contribute to neoplastic progression.
Ionizing radiation predisposes nonmalignant human mammary epithelial cells to undergo transforming growth factor beta induced epithelial to mesenchymal transition.
No sample metadata fields
View SamplesAccumulating data support the concept that ionizing radiation therapy (RT) has the potential to convert the tumor into an in situ, individualized vaccine; however this potential is rarely realized by RT alone. Transforming growth factor (TGF) is an immunosuppressive cytokine that is activated by RT and inhibits the antigen-presenting function of dendritic cells and the differentiation of effector CD8+ T cells. Here we tested the hypothesis that TGF hinders the ability of RT to promote anti-tumor immunity. Development of tumor-specific immunity was examined in a pre-clinical model of metastatic breast cancer.
TGFβ Is a Master Regulator of Radiation Therapy-Induced Antitumor Immunity.
Sex, Specimen part
View SamplesTranscriptional profiling of mammary tissue irradiated at 10 weeks of age with either 100 cGy sparsely ionizing gamma-rays, or 10 cGy or 30 cGy densely ionizing radiation (350 MeV/amu Si). Mammary tissue was collected 1 weeks, 4 weeks, and 12 weeks post-irradiation.
Irradiation of juvenile, but not adult, mammary gland increases stem cell self-renewal and estrogen receptor negative tumors.
Sex, Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Age- and pregnancy-associated DNA methylation changes in mammary epithelial cells.
Sex, Age, Specimen part
View SamplesMammary gland development and luminal differentiation occur largely postnatally during puberty and pregnancy. We found that pregnancy had the most significant effects on stem cells, inducing a distinct epigenetic state that remained stable through life.
Age- and pregnancy-associated DNA methylation changes in mammary epithelial cells.
Sex, Specimen part
View SamplesMammary gland development and luminal differentiation occur largely postnatally during puberty and pregnancy. To explore the role of DNA methylation in luminal cell differentiation and pregnancy-induced changes, we determined the genome-wide DNA methylation and gene expression profiles of mammary epithelial stem, luminal progenitor, and mature luminal cells at different reproductive stages. We found that pregnancy had the most significant effects on stem cells, inducing a distinct epigenetic state that remained stable through life. Integrated analysis of gene expression, DNA methylation, and histone modification profiles revealed cell type and reproductive stage-specific changes in molecular signatures. We also identified p27 and TGF signaling as key regulators of luminal progenitor cell proliferation based on their expression patterns and by the use of explant cultures. Our results suggest relatively minor changes in DNA methylation during luminal cell differentiation as compared to the significant effects of pregnancy on mammary epithelial stem cells.
Age- and pregnancy-associated DNA methylation changes in mammary epithelial cells.
Sex, Specimen part
View SamplesSeptic shock is the most severe complication of sepsis, associated with high mortality. The patient's response to supportive therapy is very heterogeneous and the underlying mechanisms are still elusive. In order to identify which are the actors (genes and pathways) that play a role in establishing the response, we investigate the whole blood transcriptome in septic shock patients with positive and negative responses to early supportive hemodynamic therapy, assessed by changes in SOFA scores within the first 48 hours from ICU admission. We pinpointed genes and pathways that are differently modulated and enriched respectively within 48hrs between responders and non-responders. Overall design: We analyzed 31 patients (17 Responders and 14 Not Responders to early therapy). For each patient, 2 samples were collected. In particular the first sample (T1) collected within 16 hours from ICU admission whereas the second (T2) collected within 48 hours from ICU admission. Experimental groups (Responders and Not Responders) are defined accordingly with SOFA scores improvements within 48 hours.
Identification of a transcriptome profile associated with improvement of organ function in septic shock patients after early supportive therapy.
Specimen part, Subject, Time
View Samples