T cell leukemia control via Ras-Raf pathway inhibition with peptides

RATIONALE: RAS-RAF-MEK-ERK pathway has been considered a promising target for anticancer therapy. However, tumor cells may develop resistance against such drugs via hyperactivation of N-Ras, which explains why novel therapeut-ic approaches. In this sense, the Institute Curie- Université Pierre et Marie Curie (Paris 6) designed peptides in order to disturb Ras/Raf interaction which showed pro-apoptotic properties. These peptides were patented as WO2015001045 A2 (PCT/EP2014/064243)5. OBJECTIVE: In order to check the anti-tumoral action of WO2015001045 A2 peptides in a very aggressive BALB/c mice spontaneous leukemia called LB, we performed the present study. METHOD & RESULTS: 50 BALB/c mice inoculated with 106 LB tumor cells were randomly assigned either to control (placebo) or treatment group (that daily received 3 mg of peptide per kg of mice) during 30 days. By day 15 only 24% of the control group was alive vs. 100% of the treatment group. The average survival in treated group was 20,27 days while in control group the mean survival was 15,48 days. Either bone marrow, spleen or axillary nodes demonstrated a higher level of malignant T cell presence compare with treated group (89,78% ; 95,64% & 77,68% versus 72,45%, 80,23% & 63.44% respectively for each organ inspected. DISCUSSION: Our study demonstrated an improvement in survival curves in mice model affected by spontaneous T lymphoid leukemia when peptides WO2015001045 A2 were used. These peptides might be a valid option to become part of the therapeutic armory for malignant lymphoproliferative diseases control.Facultad de Ciencias Médica

T cell leukemia control via Ras-Raf pathway inhibition with peptides

RATIONALE: RAS-RAF-MEK-ERK pathway has been considered a promising target for anticancer therapy. However, tumor cells may develop resistance against such drugs via hyperactivation of N-Ras, which explains why novel therapeut-ic approaches. In this sense, the Institute Curie- Université Pierre et Marie Curie (Paris 6) designed peptides in order to disturb Ras/Raf interaction which showed pro-apoptotic properties. These peptides were patented as WO2015001045 A2 (PCT/EP2014/064243)5. OBJECTIVE: In order to check the anti-tumoral action of WO2015001045 A2 peptides in a very aggressive BALB/c mice spontaneous leukemia called LB, we performed the present study. METHOD & RESULTS: 50 BALB/c mice inoculated with 106 LB tumor cells were randomly assigned either to control (placebo) or treatment group (that daily received 3 mg of peptide per kg of mice) during 30 days. By day 15 only 24% of the control group was alive vs. 100% of the treatment group. The average survival in treated group was 20,27 days while in control group the mean survival was 15,48 days. Either bone marrow, spleen or axillary nodes demonstrated a higher level of malignant T cell presence compare with treated group (89,78% ; 95,64% & 77,68% versus 72,45%, 80,23% & 63.44% respectively for each organ inspected. DISCUSSION: Our study demonstrated an improvement in survival curves in mice model affected by spontaneous T lymphoid leukemia when peptides WO2015001045 A2 were used. These peptides might be a valid option to become part of the therapeutic armory for malignant lymphoproliferative diseases control.Facultad de Ciencias Médica

T cell leukemia control via Ras-Raf pathway inhibition with peptides

RATIONALE: RAS-RAF-MEK-ERK pathway has been considered a promising target for anticancer therapy. However, tumor cells may develop resistance against such drugs via hyperactivation of N-Ras, which explains why novel therapeut-ic approaches. In this sense, the Institute Curie- Université Pierre et Marie Curie (Paris 6) designed peptides in order to disturb Ras/Raf interaction which showed pro-apoptotic properties. These peptides were patented as WO2015001045 A2 (PCT/EP2014/064243)5. OBJECTIVE: In order to check the anti-tumoral action of WO2015001045 A2 peptides in a very aggressive BALB/c mice spontaneous leukemia called LB, we performed the present study. METHOD & RESULTS: 50 BALB/c mice inoculated with 106 LB tumor cells were randomly assigned either to control (placebo) or treatment group (that daily received 3 mg of peptide per kg of mice) during 30 days. By day 15 only 24% of the control group was alive vs. 100% of the treatment group. The average survival in treated group was 20,27 days while in control group the mean survival was 15,48 days. Either bone marrow, spleen or axillary nodes demonstrated a higher level of malignant T cell presence compare with treated group (89,78% ; 95,64% & 77,68% versus 72,45%, 80,23% & 63.44% respectively for each organ inspected. DISCUSSION: Our study demonstrated an improvement in survival curves in mice model affected by spontaneous T lymphoid leukemia when peptides WO2015001045 A2 were used. These peptides might be a valid option to become part of the therapeutic armory for malignant lymphoproliferative diseases control.Facultad de Ciencias Médica

New forms of induction of apoptosis in aggressive lymphoma using peptides that interrupt the RAS / RAF interaction

RAS-RAF-MEK-ERK is a key pathway for apoptosis regulation in cancer cells. B-Raf-inhibitors such as PLX4032 peptide was developed by Institute Curie-Université Pierre et Marie Curie in order to induce apoptosis in cancer cells. Objective: To demonstrate pro-apoptotic properties and survival outcome of EP2014/064243 peptide in murine aggressive lymphoma. Material and methods: BALBc mice with T-lymphoma were randomized assigned either in Group A (peptide+cyclophosphamide-CFM); Group B (peptides), Group C (CFM-control) or Control D (Cl-Na 0.9%-SF control group). Survival probability was calculated by Kaplan-Meier analysis. Apoptosis was detected using TUNEL technique. The protocol was approved by the Institutional Committee for Animal Care (CICUAL: T04-01-2015). Results: The median survival was 24 days (21.6-26.4) for placebo, 33 days (28.0-35.4) for the CFM monotherapy group, 33 (27.1-35.8) for the peptide group and 34 days (24,4-40) for CFM-peptide combined treatment (p < 0.05). In lymph node tissue the mean TUNEL positive cells per field for each treatment group was 2, 12 and 13 and 35 for SF, CFM, peptide and combined therapy (p < 0.05). Conclusion: These findings suggest that in murine aggressive lymphoma treated by an experimental peptide in addition with CFM, had an exponentially pro-apoptotic effect than CFM alone, suggesting that the peptide potentiated the anti-tumoural effect of CFM.Facultad de Ciencias Médica

Distinct expression patterns of the E3 ligase SIAH-1 and its partner Kid/KIF22 in normal tissues and in the breast tumoral processes

SIAH proteins are the human members of an highly conserved family of E3 ubiquitin ligases. Several data suggest that SIAH proteins may have a role in tumor suppression and apoptosis. Previously, we reported that SIAH-1 induces the degradation of Kid (KIF22), a chromokinesin protein implicated in the normal progression of mitosis and meiosis, by the ubiquitin proteasome pathway. In human breast cancer cells stably transfected with SIAH-1, Kid/KIF22 protein level was markedly reduced whereas, the Kid/KIF22 mRNA level was increased. This interaction has been further elucidated through analyzing SIAH and Kid/KIF22 expression in both paired normal and tumor tissues and cell lines. It was observed that SIAH-1 protein is widely expressed in different normal tissues, and in cells lines but showing some differences in western blotting profiles. Immunofluorescence microscopy shows that the intracellular distribution of SIAH-1 and Kid/KIF22 appears to be modified in human tumor tissues compared to normal controls. When mRNA expression of SIAH-1 and Kid/KIF22 was analyzed by real-time PCR in normal and cancer breast tissues from the same patient, a large variation in the number of mRNA copies was detected between the different samples. In most cases, SIAH-1 mRNA is decreased in tumor tissues compared to their normal counterparts. Interestingly, in all breast tumor tissues analyzed, variations in the Kid/KIF22 mRNA levels mirrored those seen with SIAH-1 mRNAs. This concerted variation of SIAH-1 and Kid/KIF22 messengers suggests the existence of an additional level of control than the previously described protein-protein interaction and protein stability regulation. Our observations also underline the need to re-evaluate the results of gene expression obtained by qRT-PCR and relate it to the protein expression and cellular localization when matched normal and tumoral tissues are analyzed

T cell leukemia control via Ras-Raf pathway inhibition with peptides

RAS-RAF-MEK-ERK pathway has been considered a promising target for anticancer therapy. However, tumor cells may develop resistance against such drugs via hyperactivation of N-Ras, which explains why novel therapeut-ic approaches. In this sense, the Institute Curie- Université Pierre et Marie Curie (Paris 6) designed peptides in order to disturb Ras/Raf interaction which showed pro-apoptotic properties.Fil: Marin, G. H.. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; ArgentinaFil: Bruzzoni Giovanelli, H.. Universite de Paris; FranciaFil: Schinella, Guillermo Raúl. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; ArgentinaFil: Piazzon, Margarita Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Duarte, Alejandra Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Errecalde, J.. Universidad Nacional de la Plata. Facultad de Ciencias Médicas; Argentin

SIAH-1 inhibits cell growth by altering the mitotic process

International audienceSIAH-1, the human homologue of the drosophila seven in absentia gene, is a p53-p21Waf-1 inducible gene. We report that stable transfection with SIAH-1 of the epithelial breast cancer cell line MCF-7 blocks its growth process. The transfectants show a redistribution of SIAH-1 protein within the nucleus, more specifically to the nuclear matrix, associated to dramatic changes in cell morphology and defective mitosis. Multinucleated giant cells (2-12 nuclei in more than 50% cells) were a most striking observation associated with tubulin spindle disorganization and defective cytokinesis. There were also present at high frequency abortive mitotic figures, DNA bridges and persistance of intercellular bridges and midbodies, along with an increased expression of p21Waf-1. These results indicate that the mechanism of growth arrest induced by SIAH-1 in MCF-7 cells involves disorganization of the mitotic program, mainly during nuclei separation and cytokinesis

p21WAF-1 reorganizes the nucleus in tumor suppression

International audienceInterphasic nuclear organization has a key function in genome biology. We demonstrate that p21WAF-1, by influencing gene expression and inducing chromosomal repositioning in tumor suppression, plays a major role as a nuclear organizer. Transfection of U937 tumor cells with p21WAF-1 resulted in expression of the HUMSIAH (human seven in absentia homologue), Rb, and Rbr-2 genes and strong suppression of the malignant phenotype. p21(WAF-1) drastically modified the compartmentalization of the nuclear genome. DNase I genome exposure and fluorescence in situ hybridization show, respectively, a displacement of the sensitive sites to the periphery of the nucleus and repositioning of chromosomes 13, 16, 17, and 21. These findings, addressing nuclear architecture modulations, provide potentially significant perspectives for the understanding of tumor suppression