Deficiency in p53 is required for doxorubicin induced transcriptional activation of NF-кB target genes in human breast cancer

NF-кB has been linked to doxorubicin resistance in breast cancer patients. NF- кB nuclear translocation and DNA binding in doxorubicin treated-breast cancer cells have been extensively examined; however its functional relevance at transcriptional level on NF-кB -dependent genes and the biological consequences are unclear. We studied NF-кB -dependent gene expression induced by doxorubicin in breast cancer cells and fresh human cancer specimens with different genetic backgrounds focusing on their p53 status. NF-кB –dependent signature of doxorubicin was identified by gene expression microarrays in breast cancer cells treated with doxorubicin and the IKKβ-inhibitor MLN120B, and confirmed ex vivo in human cancer samples. The association with p53 was functionally validated. Finally, NF-кB activation and p53 status was determined in a cohort of breast cancer patients treated with adjuvant doxorubicin-based chemotherapy. Doxorubicin treatment in the p53-mutated MDA-MB-231 cells resulted in NF NF- кB driven-gene transcription signature. Modulation of genes related with invasion, metastasis and chemoresistance (ICAM-1, CXCL1, TNFAIP3, IL8) were confirmed in additional doxorubicin-treated cell lines and fresh primary human breast tumors. In both systems, p53-deficient background correlated with the activation of the NF-кB –dependent signature. Furthermore, restoration of p53WT in the mutant p53 MDAMB- 231 cells impaired NF-кB driven transcription induced by doxorubicin. Moreover, a p53 deficient background and nuclear NF-кB /p65 in breast cancer patients correlated with reduced disease free-survival. This study supports that p53 deficiency is necessary for a doxorubicin driven NF-кB -response that limits doxorubicin cytotoxicity in breast cancer and is linked to an aggressive clinical behavior.Financial support: This work was supported by RD12/0036/0051 (J.A.), RD09/0076/0101, RD09/0076/0036, RD12/0036/0054 (A.B), RD12/0036/0070 (A. Ll), PI12/00680 (J.A.), PI12/01552 (F.R.), PI12/01421 (A.Ll.), 2009 SGR 321 (J.A.), FMM 9757/002 (F.R.), and the “Xarxa de Bancs de tumors sponsored by Pla Director d’Oncologia de Catalunya (XBTC). J.A. and F.R. are recipients of intensification program ISCIII/FEDER. We thank Fundació Cellex (Barcelona) for a generous donation to the Hospital del Mar Medical Oncology Service. We thank Millenium for generously providing MLN120B

Inhibition of Specific NF-κB Activity Contributes to the Tumor Suppressor Function of 14-3-3σ in Breast Cancer

14-3-3σ is frequently lost in human breast cancers by genetic deletion or promoter methylation. We have now investigated the involvement of 14-3-3σ in the termination of NF-κB signal in mammary cells and its putative role in cancer relapse and metastasis. Our results show that 14-3-3σ regulates nuclear export of p65-NF-κB following chronic TNFα stimulation. Restoration of 14-3-3σ in breast cancer cells reduces migration capacity and metastatic abilities in vivo. By microarray analysis, we have identified a genetic signature that responds to TNFα in a 14-3-3σ-dependent manner and significantly associates with different breast and other types of cancer. By interrogating public databases, we have found that over-expression of this signature correlates with poor relapse-free survival in breast cancer patients. Finally, screening of 96 human breast tumors showed that NF-κB activation strictly correlates with the absence of 14-3-3σ and it is significantly associated with worse prognosis in the multivariate analysis. Our findings identify a genetic signature that is important for breast cancer prognosis and for future personalized treatments based on NF-κB targeting

Famílies botàniques de plantes medicinals

Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia, Assignatura: Botànica Farmacèutica, Curs: 2013-2014, Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són els recull de 175 treballs d’una família botànica d’interès medicinal realitzats de manera individual. Els treballs han estat realitzat per la totalitat dels estudiants dels grups M-2 i M-3 de l’assignatura Botànica Farmacèutica durant els mesos d’abril i maig del curs 2013-14. Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pel professor de l’assignatura i revisats i finalment co-avaluats entre els propis estudiants. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica

Acquired resistance to the anti-EFGR monoclonal antibody cetuximab in colorectal cancer

EGFR is a transmembrane tyrosine kinase receptor from the HER family which, upon ligand stimulation, activates different signaling pathways involved in tumorogenesis. EGFR can be targeted by monoclonal antibodies, as cetuximab and panitumumab, which bind to EGFR preventing ligand stimulation of the receptor. Cetuximab and panitumumab are approved for colorectal cancer treatment. However, its clinical success is uniformily limited by the development of acquired drug resistance. We describe a new mechanism of acquired resistance to cetuximab in colorectal cancer that was due to a missense mutation in the EGFR ectodomain (S492R mutation). Upon chronic exposure to cetuximab, colorectal cancer cell lines acquired S492R mutation and became resistant to the treatment. We observed that cetuximab was not able to bind mutant EGFR. Notably, this amino acid change did not affect the ability of panitumumab to bind to EGFR, and panitumumab effectively suppressed growth of mutant cells. EGFRS492R mutation was detected in 2 out of 10 tumor specimens from patients following progression on cetuximab. One of these patients was subsequently treated with single agent panitumumab yielding a partial response. The S492R mutation defines a novel biomarker of resistance to cetuximab but not to panitumumab in colorectal cancerEGFR és un receptor transmembrana tirosina cinasa de la família HER el qual, després de l’estimulació mitjançant lligands, activa vies de senyalització involucrades en processos tumorogènics. L’EGFR es pot inhibir amb anticossos monoclonals, com cetuximab i panitumumab, que s’uneixen al receptor prevenint-ne l’activació per part dels lligands. Cetuximab i panitumumab estan aprovats per al tractament del càncer colorectal, però el seu ús es veu limitat per el desenvolupament de resistència adquirida al tractament. Nosaltres describim un mecanisme de resistència adquirida a cetuximab en càncer colorectal degut a l’adquisió d’una mutació en el domini extracel•lular de l’EGFR, la mutació S492R. Durant l’exposició crònica a cetuximab, linies cel•lulars de càncer colorectal van adquirir la mutació S492R tornat-se resistents al tractament. Cetuximab no era capaç d’unir-se a l’EGFR mutat. Aquests canvi d’aminoàcid no afectava a l’habilitat que té panitumumab a unir-se al EGFR, pertant, panitumumab suprimia el creixement de les cèl•lules tumorals mutades. Vam detectar la mutació EGFRS492R en 2 de 10 mostres tumorals de pacients que havien recaigut al tractament amb cetuximab. Un d’aquest pacients va ser posteriorment tractat amb panitumumab obtenint-ne una resposta tumoral parcial. La mutació S492R defineix un nou mecanisme de resistència a cetuximab però no a panitumumab en el tractament del càncer colorectal

Predictors of Metachronous Risk Polyps After Index Colonoscopy

Altres ajuts: Associación Española Contra el Cáncer (AECC) (PS14152544ANDR)We included patients with high-risk lesions (HRLs), defined as advanced adenoma (AA), large serrated polyps (SPs), and multiplicity (≥3 of any adenomas/SPs). Data on age, sex, cardiovascular risk factors, pharmacological treatment, and the histological characteristics in each individual, and mutations in genes involved in the most advanced index polyp, were collected. Parameters independently associated with a metachronous HRL diagnosis were evaluated through univariate and multivariate analyses. The results are reported as odds ratios and 95% confidence intervals along with P values. A total of 537 cases (median age: 60.7 years; 66% male) were included. Dyslipidemia and smoking correlated with metachronous HRLs. Multivariate logistic regression analysis showed that the presence of multiplicity with ≥3 polyps on the index colonoscopy was significantly associated with metachronous HRL, AA, proximal AA, and ≥3 polyps at 3 years. In addition, independent predictors of metachronous proximal AA were increasing age, female sex, and the loss of expression of the MLH1 protein. Multiplicity was a strong predictor of HRLs at 3 years, although the inclusion of other clinical variables (age, sex, smoking status, and dyslipidemia) improves surveillance recommendations. Without these risk factors, the surveillance could be extended to 5 years; we propose examining the somatic expression of MHL1 in all patients

Inhibition of specific NF-KB activity contributes to the tumor suppressor function of 14-3-3omega in breast cancer

14-3-3σ is frequently lost in human breast cancers by genetic deletion or promoter methylation. We have now investigated the involvement of 14-3-3σ in the termination of NF-κB signal in mammary cells and its putative role in cancer relapse and metastasis. Our results show that 14-3-3σ regulates nuclear export of p65-NF-κB following chronic TNFα stimulation. Restoration of 14-3-3σ in breast cancer cells reduces migration capacity and metastatic abilities in vivo. By microarray analysis, we have identified a genetic signature that responds to TNFα in a 14-3-3σ-dependent manner and significantly associates with different breast and other types of cancer. By interrogating public databases, we have found that over-expression of this signature correlates with poor relapse-free survival in breast cancer patients. Finally, screening of 96 human breast tumors showed that NF-κB activation strictly correlates with the absence of 14-3-3σ and it is significantly associated with worse prognosis in the multivariate analysis. Our findings identify a genetic signature that is important for breast cancer prognosis and for future personalized treatments based on NF-κB targeting.This work was funded by ISCIII/FEDER-Subdirección General de Evaluación y Fomento de la Investigación (PI07/0778, PI10/01128, PS09/1296 and PS09/01285), AGAUR (2009SGR23 and 2009SGR321) and Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+I), iniciativa Ingenio 2010, Programa Consolider and Instituto de Salud Carlos III (ISCIII)/FEDER (RD06/0020/0098 and RD06/0020/0109). Financial support was provided to RRG by BBVA foundation and Asociación Española Contra el Cáncer. NLB acknowledges funding from the Spanish Ministry of Science and Technology (SAF2009-06954). AJ-S was funded by Science and Education Spanish Ministry (MEC) FPI predoctoral fellowship (BES-2008-001850). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip

Relapse-free survival analysis.

<p>Abreviations: DFS, disease free survival; HR, hazard ratio; CI, confidence interval; HER2, human epidermal growth factor receptor 2.</p><p>Relapse free survival analysis of the group of patients that were studied for the presence of nuclear p65. Commonly used clinical predictors such as tumor grade and size, or the number of infiltrated lymph nodes were studied in comparison with the status of p65.</p