Distinct roles for PARP-1 and PARP-2 in c-Myc-driven B-cell lymphoma in mice

Dysregulation of the c-Myc oncogene occurs in a wide variety of hematologic malignancies, and its overexpression has been linked with aggressive tumor progression. Here, we show that poly (ADP-ribose) polymerase 1 (PARP-1) and PARP-2 exert opposing influences on progression of c-Myc-driven B-cell lymphoma. PARP-1 and PARP-2 catalyze the synthesis and transfer of ADP-ribose units onto amino acid residues of acceptor proteins in response to DNA strand breaks, playing a central role in the response to DNA damage. Accordingly, PARP inhibitors have emerged as promising new cancer therapeutics. However, the inhibitors currently available for clinical use are not able to discriminate between individual PARP proteins. We found that genetic deletion of PARP-2 prevents c-Myc-driven B-cell lymphoma, whereas PARP-1 deficiency accelerates lymphomagenesis in the E¿-Myc mouse model of aggressive B-cell lymphoma. Loss of PARP-2 aggravates replication stress in preleukemic E¿-Myc B cells, resulting in accumulation of DNA damage and concomitant cell death that restricts the c-Myc-driven expansion of B cells, thereby providing protection against B-cell lymphoma. In contrast, PARP-1 deficiency induces a proinflammatory response and an increase in regulatory T cells, likely contributing to immune escape of B-cell lymphoma, resulting in an acceleration of lymphomagenesis. These findings pinpoint specific functions for PARP-1 and PARP-2 in c-Myc-driven lymphomagenesis with antagonistic consequences that may help inform the design of new PARP-centered therapeutic strategies, with selective PARP-2 inhibition potentially representing a new therapeutic approach for the treatment of c-Myc-driven tumors.The J.Y. laboratory is funded by the Spanish Ministerio de Economía, Industria y Competitividad (grant SAF2017-83565-R), Spanish Ministerio de Ciencia e Innovación (grant PID2020-112526RB-I00), and Fundación Científica de la Asociación Española Contra el Cáncer (grant PROYEI6018YÉLA). Work in the J.E.S. laboratory is supported by a core grant to the Laboratory of Molecular Biology from the Medical Research Council (U105178808). The F.D. laboratory is supported by a Laboratory of Excellence grant (ANR-10-LABX-0034_Medalis) to Strasbourg University, Centre National de la Recherche Scientifique. The P.N. laboratory is supported by grants from the Spanish Ministry of Economy and Competitiveness/Instituto de Salud Carlos III–Fondo Europeo de Desarrollo Regional (FEDER; PI17/00199 and PI20/00625) and the Generalitat de Catalunya (2017-SGR-225). The P.M. laboratory acknowledges support from Centres de Recerca de Catalunya/Generalitat de Catalunya and Fundació Josep Carreras-Obra Social la Caixa for core support, the Spanish Ministry of Economy and Competitiveness (grant SAF-2019-108160-R), the Fundación Uno entre Cienmil, the Obra Social La Caixa (grant LCF/PR/HR19/52160011), and the German Josep Carreras Leukamie Stiftung. Work at the G.R. and P.M. laboratories are cofinanced by the European Regional Development Fund through the Interreg V-A Spain-France-Andorra Program (project PROTEOblood; grant EFA360/19). The O.F.-C. laboratory is funded by grants from the Spanish Ministry of Science, Innovation and Universities (RTI2018-102204-B-I00; cofinanced with European FEDER funds) and the European Research Council (ERC-617840). T.V.-H. was supported by a Marie Sklodowska Curie fellowship (GA792923). The A.B. laboratory is supported by the Spanish Ministry of Economy and Competitiveness (grant PID2019-104695RB-I00)

Pharmacogenetic profile of xenobiotic enzyme metabolism in survivors of the Spanish toxic oil syndrome

7 pages, 3 figures, 5 tables.-- PMID: 11335185 [PubMed].-- PMCID: PMC1240277.-- Printed version published Apr 2001.In 1981, the Spanish toxic oil syndrome (TOS) affected more than 20,000 people, and over 300 deaths were registered. Assessment of genetic polymorphisms on xenobiotic metabolism would indicate the potential metabolic capacity of the victims at the time of the disaster. Thus, impaired metabolic pathways may have contributed to the clearance of the toxicant(s) leading to a low detoxification or accumulation of toxic metabolites contributing to the disease. We conducted a matched case-control study using 72 cases (54 females, 18 males) registered in the Official Census of Affected Patients maintained by the Spanish government. Controls were nonaffected siblings (n =72) living in the same household in 1981 and nonaffected nonrelatives (n = 70) living in the neighborhood at that time, with no ties to TOS. Genotype analyses were performed to assess the metabolic capacity of phase I [cytochrome P450 1A1 (CYP1A1), CYP2D6] and phase II [arylamine N-acetyltransferase-2 (NAT2), GSTM1 (glutathione S-transferase M1) and GSTT1] enzyme polymorphisms. The degree of association of the five metabolic pathways was estimated by calculating their odds ratios (ORs) using conditional logistic regression analysis. In the final model, cases compared with siblings (72 pairs) showed no differences either in CYP2D6 or CYP1A1 polymorphisms, or in conjugation enzyme polymorphisms, whereas cases compared with the unrelated controls (70 pairs) showed an increase in NAT2 defective alleles [OR = 6.96, 95% confidence interval (CI), 1.46-33.20] adjusted by age and sex. Glutathione transferase genetic polymorphisms (GSTM1, GSTT1) showed no association with cases compared with their siblings or unrelated controls. These findings suggest a possible role of impaired acetylation mediating susceptibility in TOS.The study was supported by grants 94/1828–1829 from the Fondo de Investigación Sanitaria (Spain). The present study generated a patient DNA collection deposited in the CISAT Center (Madrid), Centro de Investigación Sobre el Síndrome del Aceite de Colza.Peer reviewe

Selective PARP 2 inhibition hampers pancreatic cancer tumorigenesis and progression

Trabajo presentado en el 18th ASEICA International Congress, celebrado en Santiago de Compostela (España), del 16 al 18 de noviembre de 202

Attenuation of tumor burden in response to rucaparib in lung aAdenocarcinoma: the contribution of oxidative stress, apoptosis, and DNA damage

In cancer, overactivation of poly (ADPribose) polymerases (PARP) plays a relevant role in DNA repair. We hypothesized that treatment with the PARP inhibitor rucaparib may reduce tumor burden via several biological mechanisms (apoptosis and oxidative stress) in mice. In lung tumors (LP07 lung adenocarcinoma) of mice treated/non-treated (control animals) with PARP inhibitor (rucaparib,150 mg/kg body weight/24 h for 20 day), PARP activity and expression, DNA damage, apoptotic nuclei, cell proliferation, and redox balance were measured using immunoblotting and immunohistochemistry. In lung tumors of rucaparib-treated mice compared to non-treated animals, tumor burden, PARP activity, and cell proliferation decreased, while DNA damage, TUNEL-positive nuclei, protein oxidation, and superoxide dismutase content (SOD)2 increased. In this experiment on lung adenocarcinoma, the pharmacological PARP inhibitor rucaparib elicited a significant improvement in tumor size, probably through a reduction in cell proliferation as a result of a rise in DNA damage and apoptosis. Oxidative stress and SOD2 also increased in response to treatment with rucaparib within the tumor cells of the treated mice. These results put the line forward to the contribution of PARP inhibitors to reduced tumor burden in lung adenocarcinoma. The potential implications of these findings should be tested in clinical settings of patients with lung tumors.This study has been funded by Instituto de Salud Carlos III through the project “FI19/00001” (Co-funded by European Social Fund “Investing in your future”). María Pérez-Peiró was a recipient of a predoctoral fellowship from FIS Contratos Predoctorales de Formación en Investigación en Salud. The current research has been supported by project FIS 18/00075 funded by Instituto de Salud Carlos III (ISCIII) and co-funded by the European Union and Consorcio Centro de Investigación Biomédica en Red (CIBERES) 2022 funded by Instituto de Salud Carlos III (ISCIII), Spanish Ministry of Science and Innovation and European Union; Spanish Respiratory Society (SEPAR), contract grant numbers, SEPAR 2018. The Yélamos lab is funded by the Spanish Ministry of Science and Innovation (grant PID2020-112526RB-I00 funded by MCIN/AEI/10.13039/501100011033)

Pharmacogenetic profile of xenobiotic enzyme metabolism in survivors of the Spanish toxic oil syndrome

In 1981, the Spanish toxic oil syndrome (TOS) affected more than 20,000 people, and over 300 deaths were registered. Assessment of genetic polymorphisms on xenobiotic metabolism would indicate the potential metabolic capacity of the victims at the time of the disaster. Thus, impaired metabolic pathways may have contributed to the clearance of the toxicant(s) leading to a low detoxification or accumulation of toxic metabolites contributing to the disease. We conducted a matched case-control study using 72 cases (54 females, 18 males) registered in the Official Census of Affected Patients maintained by the Spanish government. Controls were nonaffected siblings (n =72) living in the same household in 1981 and nonaffected nonrelatives (n = 70) living in the neighborhood at that time, with no ties to TOS. Genotype analyses were performed to assess the metabolic capacity of phase I [cytochrome P450 1A1 (CYP1A1), CYP2D6] and phase II [arylamine N-acetyltransferase-2 (NAT2), GSTM1 (glutathione S-transferase M1) and GSTT1] enzyme polymorphisms. The degree of association of the five metabolic pathways was estimated by calculating their odds ratios (ORs) using conditional logistic regression analysis. In the final model, cases compared with siblings (72 pairs) showed no differences either in CYP2D6 or CYP1A1 polymorphisms, or in conjugation enzyme polymorphisms, whereas cases compared with the unrelated controls (70 pairs) showed an increase in NAT2 defective alleles [OR = 6.96, 95% confidence interval (CI), 1.46-33.20] adjusted by age and sex. Glutathione transferase genetic polymorphisms (GSTM1, GSTT1) showed no association with cases compared with their siblings or unrelated controls. These findings suggest a possible role of impaired acetylation mediating susceptibility in TOS.The study was supported by grants 94/1828-1829 from the Fondo de Investigación Sanitaria (Spain). The present study generated a patient DNA collection deposited in the CISAT Center (Madrid), Centro de Investigación Sobre el Síndrome del Aceite de Colza.S

Increased PARP activity and DNA damage in NSCLC patients: the influence of COPD

Background: Lung cancer (LC) is a major leading cause of death worldwide. Poly (ADP-ribose) polymerase (PARP)-1 and PARP-2 are key players in cancer. We aimed to assess PARP-1 and PARP-2 expression and activity and DNA damage in tumors and non-tumor lungs from patients with/without chronic obstructive pulmonary disease (COPD). (2) Methods: Lung tumor and non-tumor specimens were obtained through video-assisted thoracoscopic surgery (VATS) in LC patients with/without underlying COPD (two groups of patients, n = 15/group). PARP-1 and PARP-2 expression (ELISA), PARP activity (PARP colorimetric assay kit) and DNA damage (immunohistochemistry) levels were identified in all samples. (3) Results: Both PARP-1 and PARP-2 expression levels were significantly lower in lung tumors (irrespective of COPD)compared to non-tumor specimens, while DNA damage and PARP activity levels significantly increased in lung tumors compared to non-tumor specimens only in LC-COPD patients. PARP-2 expression was positively correlated with smoking burden in LC-COPD patients. (4) Conclusions: In lung tumors of COPD patients, an overactivation of PARP enzyme was observed. A decline in PARP-1 and PARP-2 protein expression was seen in lung tumors irrespective of COPD. Other phenotypic features (airway obstruction) beyond cancer may account for the increase in PARP activity seen in the tumors of patients with underlying COPD

Coordinated signals from the DNA repair enzymes PARP-1 and PARP-2 promotes B-cell development and function

International audiencePoly (ADP-ribose) polymerase (PARP)-1 and PARP-2 regulate the function of various DNA-interacting proteins by transferring ADP-ribose emerging from catalytic cleavage of cellular β-NAD+. Hence, mice lacking PARP-1 or PARP-2 show DNA perturbations ranging from altered DNA integrity to impaired DNA repair. These effects stem from the central role that PARP-1 and PARP-2 play on the cellular response to DNA damage. Failure to mount a proper response culminates in cell death. Accordingly, PARP inhibitors are emerging as promising drugs in cancer therapy. However, the full impact of these inhibitors on immunity, including B-cell antibody production, remains elusive. Given that mice carrying dual PARP-1 and PARP-2 deficiency develop early embryonic lethality, we crossed PARP-1-deficient mice with mice carrying a B-cell-conditional PARP-2 gene deletion. We found that the resulting dually PARP-1 and PARP-2 deficient mice had perturbed bone-marrow B-cell development as well as profound peripheral depletion of transitional and follicular but not marginal zone B-cells. Of note, bone-marrow B-cell progenitors and peripheral mature B-cells were conserved in mice carrying either PARP-1 or PARP-2 deficiency. In dually PARP-1 and PARP-2 deficient mice, B-cell lymphopenia was associated with increased DNA damage and accentuated death in actively proliferating B-cells. Moreover, dual PARP-1 and PARP-2 deficiency impaired antibody responses to T-independent carbohydrate but not to T-dependent protein antigens. Notwithstanding the pivotal role of PARP-1 and PARP-2 in DNA repair, combined PARP-1 and PARP-2 deficiency did not perturb the DNA-editing processes required for the generation of a protective antibody repertoire, including Ig V(D)J gene recombination and IgM-to-IgG class switching. These findings provide key information as to the potential impact of PARP inhibitors on humoral immunity, which will facilitate the development of safer PARP-targeting regimens against cancer