118 research outputs found
RelA/NF-kappaB recruitment on the bax gene promoter antagonizes p73-dependent apoptosis in costimulated T cells
The balance between antiapoptotic and proapoptotic proteins of the Bcl-2 family is critical in determining the fate of T cells in response to death stimuli. Proapoptotic genes, such as bax, are generally regulated by the p53 family of transcription factors, whereas NF-kappaB subunits can activate the transcription of antiapoptotic Bcl-2 members. Here, we show that CD28 activation protects memory T cells from irradiation-induced apoptosis by both upregulating bcl-xL and inhibiting bax gene expression. We found that p73, but not p53, binds to and trans-activates the bax gene promoter in irradiated T cells. The activation of RelA/NF-kappaB subunit in CD28 costimulated T cells and its binding onto the bax gene promoter results in suppression of bax transcription and decrease in both p73 and RNA polymerase II recruitment in vivo. RelA recruitment on the bax gene promoter is also accompanied by the lost of p300 binding and the parallel appearance of histone deacetylase-1-containing complexes. These findings identify RelA/NF-kappaB as a critical regulator of T-cell survival by affecting the balance of Bcl-2 family members
Long‐Term prognosis in children with hypertrophic cardiomyopathy: An analysis of 37 patients aged ≤ 14 years at diagnosis
The relation of clinical, electrocardiographic, and hemodynamic findings at diagnosis to presenting features and prognosis of hypertrophic cardiomyopathy in childhood was evaluated in 37 consecutive patients below 14 years of age at time of diagnosis (24 males and 13 females, mean age 7 +/- 4 years). A left ventricular out-flow tract gradient (mean 42 +/- 27 mmHg) was detected at cardiac catheterization in 13 (35%) patients. Clinical, electrocardiographic, and hemodynamic features in patients with and without a pressure gradient were similar. Patients who had moderate to severe functional limitation had a higher incidence of syncopal episodes (p less than 0.001), lower ejection fraction (p less than 0.01), raised pulmonary artery pressure (p less than 0.001), and left ventricular end-diastolic pressure (p less than 0.01). During a follow-up of 9.2 +/- 5.1 years (range 2-18), 9 (24%) patients died suddenly (2 with a recorded left ventricular outflow tract gradient). Univariate analysis showed that reduced ejection fraction (p = 0.0001), syncopal episodes (p = 0.003), increased left ventricular end-diastolic pressure (p = 0.03), and severe dyspnea (p = 0.04) were associated with a poor prognosis. However, multivariate analysis revealed ejection fraction (p = 0.0001) and syncopal episodes (p = 0.0097) as independent predictors of survival. In conclusion, sudden cardiac death was common and was well predicted by the combination of left ventricular dysfunction and syncope at time of diagnosis
Distal left circumflex coronary artery flow reserve recorded by transthoracic Doppler echocardiography: a comparison with Doppler-wire
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Beta 1-integrin-c-Met cooperation reveals an inside-in survival signalling on autophagy-related endomembranes
This work is licensed under a Creative Commons Attribution 4.0
International License. The images or other third party material in this
article are included in the article’s Creative Commons license, unless indicated otherwise
in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material.
To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/R.B.M. was a recipient of a UK Medical Research Council (MRC) studentship, MRC
Centenary Award, Barts and The London Charity (472/1711) and Rosetrees Trust
(M314), N.K. was a recipient of an MRC studentship (MR/J500409/1), C.J. was a recipient
of the Barts and The London Charitable Foundation Scholarship (RAB 05/PJ/07),
L.M. was supported by CR-UK, Breast Cancer Now (2008NovPR10) and Rosetrees Trust
(M346), A.H. was a recipient of a CR-UK studentship (C236/A11795). P.J.P. was
supported by CR-UK. J.I. was supported by grants from the Academy of Finland, ERC
Starting grant, Finnish Cancer Organisations and Sigrid Juselius Foundation. S.K. was
supported by the MRC (G0501003) and The British Lung Foundation (CAN09-4)
Response of Estrogen Receptor-Positive Breast Cancer Tumorspheres to Antiestrogen Treatments
Estrogen signaling plays a critical role in the pathogenesis of breast cancer.
Because the majority of breast carcinomas express the estrogen receptor ERα,
endocrine therapy that impedes estrogen-ER signaling reduces breast cancer
mortality and has become a mainstay of breast cancer treatment. However,
patients remain at continued risk of relapse for many years after endocrine
treatment. It has been proposed that cancer recurrence may be attributed to
cancer stem cells (CSCs)/tumor-initiating cells (TICs). Previous studies in
breast cancer have shown that such cells can be enriched and propagated
in vitro by culturing the cells in suspension as
mammospheres/tumorspheres. Here we established tumorspheres from
ERα-positive human breast cancer cell line MCF7 and investigated their
response to antiestrogens Tamoxifen and Fulvestrant. The tumorsphere cells
express lower levels of ERα and are more tumorigenic in xenograft assays
than the parental cells. Both 4-hydroxytamoxifen (4-OHT) and Fulvestrant
attenuate tumorsphere cell proliferation, but only 4-OHT at high concentrations
interferes with sphere formation. However, treated tumorsphere cells retain the
self-renewal capacity. Upon withdrawal of antiestrogens, the treated cells
resume tumorsphere formation and their tumorigenic potential remains undamaged.
Depletion of ERα shows that ERα is dispensable for tumorsphere formation
and xenograft tumor growth in mice. Surprisingly, ERα-depleted tumorspheres
display heightened sensitivity to 4-OHT and their sphere-forming capacity is
diminished after the drug is removed. These results imply that 4-OHT may inhibit
cellular targets besides ERα that are essential for tumorsphere growth, and
provide a potential strategy to sensitize tumorspheres to endocrine
treatment
Re-surgery and chest wall re-irradiation for recurrent breast cancer - a second curative approach
A phase II study of sequential neoadjuvant gemcitabine plus doxorubicin followed by gemcitabine plus cisplatin in patients with operable breast cancer: prediction of response using molecular profiling
This study examined the pathological complete response (pCR) rate and safety of sequential gemcitabine-based combinations in breast cancer. We also examined gene expression profiles from tumour biopsies to identify biomarkers predictive of response. Indian women with large or locally advanced breast cancer received 4 cycles of gemcitabine 1200 mg m−2 plus doxorubicin 60 mg m−2 (Gem+Dox), then 4 cycles of gemcitabine 1000 mg m−2 plus cisplatin 70 mg m−2 (Gem+Cis), and surgery. Three alternate dosing sequences were used during cycle 1 to examine dynamic changes in molecular profiles. Of 65 women treated, 13 (24.5% of 53 patients with surgery) had a pCR and 22 (33.8%) had a complete clinical response. Patients administered Gem d1, 8 and Dox d2 in cycle 1 (20 of 65) reported more toxicities, with G3/4 neutropenic infection/febrile neutropenia (7 of 20) as the most common cycle-1 event. Four drug-related deaths occurred. In 46 of 65 patients, 10-fold cross validated supervised analyses identified gene expression patterns that predicted with ⩾73% accuracy (1) clinical complete response after eight cycles, (2) overall clinical complete response, and (3) pCR. This regimen shows strong activity. Patients receiving Gem d1, 8 and Dox d2 experienced unacceptable toxicity, whereas patients on other sequences had manageable safety profiles. Gene expression patterns may predict benefit from gemcitabine-containing neoadjuvant therapy
Lack of evidence for KRAS oncogenic mutations in triple-negative breast cancer
<p>Abstract</p> <p>Background</p> <p>Mutational analysis of the <it>KRAS </it>gene has recently been established as a complementary <it>in vitro </it>diagnostic tool for the identification of patients with colorectal cancer who will not benefit from anti-epidermal growth factor receptor (EGFR) therapies. Assessment of the mutation status of <it>KRAS </it>might also be of potential relevance in other EGFR-overexpressing tumors, such as those occurring in breast cancer. Although <it>KRAS </it>is mutated in only a minor fraction of breast tumors (5%), about 60% of the basal-like subtype express EGFR and, therefore could be targeted by EGFR inhibitors. We aimed to study the mutation frequency of <it>KRAS </it>in that subtype of breast tumors to provide a molecular basis for the evaluation of anti-EGFR therapies.</p> <p>Methods</p> <p>Total, genomic DNA was obtained from a group of 35 formalin-fixed paraffin-embedded, triple-negative breast tumor samples. Among these, 77.1% (27/35) were defined as basal-like by immunostaining specific for the established surrogate markers cytokeratin (CK) 5/6 and/or EGFR. <it>KRAS </it>mutational status was determined in the purified DNA samples by Real Time (RT)-PCR using primers specific for the detection of wild-type <it>KRAS </it>or the following seven oncogenic somatic mutations: Gly12Ala, Gly12Asp, Gly12Arg, Gly12Cys, Gly12Ser, Gly12Val and Gly13Asp.</p> <p>Results</p> <p>We found no evidence of <it>KRAS </it>oncogenic mutations in all analyzed tumors.</p> <p>Conclusions</p> <p>This study indicates that <it>KRAS </it>mutations are very infrequent in triple-negative breast tumors and that EGFR inhibitors may be of potential benefit in the treatment of basal-like breast tumors, which overexpress EGFR in about 60% of all cases.</p
Integrins as therapeutic targets: lessons and opportunities.
The integrins are a large family of cell adhesion molecules that are essential for the regulation of cell growth and function. The identification of key roles for integrins in a diverse range of diseases, including cancer, infection, thrombosis and autoimmune disorders, has revealed their substantial potential as therapeutic targets. However, so far, pharmacological inhibitors for only three integrins have received marketing approval. This article discusses the structure and function of integrins, their roles in disease and the chequered history of the approved integrin antagonists. Recent advances in the understanding of integrin function, ligand interaction and signalling pathways suggest novel strategies for inhibiting integrin function that could help harness their full potential as therapeutic targets
Phase 1 trial of the antiangiogenic peptide ATN-161 (Ac-PHSCN-NH2), a beta integrin antagonist, in patients with solid tumours
To evaluate the toxicity, pharmacological and biological properties of ATN-161, a five –amino-acid peptide derived from the synergy region of fibronectin, adult patients with advanced solid tumours were enrolled in eight sequential dose cohorts (0.1–16 mg kg−1), receiving ATN-161 administered as a 10-min infusion thrice weekly. Pharmacokinetic sampling of blood and urine over 7 h was performed on Day 1. Twenty-six patients received from 1 to 14 4-week cycles of treatment. The total number of cycles administered to all patients was 86, without dose-limiting toxicities. At dose levels above 0.5 mg kg−1, mean total clearance and volume of distribution showed dose-independent pharmacokinetics (PKs). At 8.0 and 16.0 mg kg−1, clearance of ATN-161 was reduced, suggesting saturable PKs. Dose escalation was halted at 16 mg kg−1 when drug exposure (area under the curve) exceeded that associated with efficacy in animal models. There were no objective responses. Six patients received more than four cycles of treatment (>112 days). Three patients received 10 or more cycles (⩾280 days). ATN-161 was well tolerated at all dose levels. Approximately, 1/3 of the patients in the study manifested prolonged stable disease. These findings suggest that ATN-161 should be investigated further as an antiangiogenic and antimetastatic cancer agent alone or with chemotherapy
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