An update on PARP inhibitors for the treatment of cancer.
Ontology highlight
ABSTRACT:
SUBMITTER: Benafif S
PROVIDER: S-EPMC4348139 | biostudies-literature | 2015
REPOSITORIES: biostudies-literature
Publications
An update on PARP inhibitors for the treatment of cancer.
OncoTargets and therapy 20150226
The development of poly (adenosine diphosphate [ADP]) ribose polymerase (PARP) inhibitors (PARPi) has progressed greatly over the last few years and has shown encouraging results in the BRCA1/2 mutation-related cancers. This article attempts to summarize the rationale and theory behind PARPi, the clinical trials already reported, as well as ongoing studies designed to determine the role of PARPi in patients with and without germline mutations of BRCA genes. Future plans for PARPi both as monothe ...[more]
Similar Datasets
Project description:OPINION STATEMENT:The single agent activity of PARP inhibitors (PARPi) in germline BRCA mutated (gBRCAm) breast and ovarian cancer suggests untapped potential for this new class of drug in breast cancer. The US Food and Drug Administration has approved three PARPi (olaparib, rucaparib, and niraparib) so far to treat certain ovarian cancers, including those with gBRCAm and olaparib for treatment of gBRCAm breast cancers. Several PARPi are now under clinical development for breast cancer in the various treatment settings. Recently, two phase III trials of olaparib (OlympiaD) and talazoparib (EMBRACA) demonstrated 3-month progression-free survival improvement with PARPi compared to physician's choice single agent chemotherapy in metastatic gBRCAm breast cancer. To date, PARPi seems less efficacious in metastatic breast cancer patients than those with BRCA mutated platinum-sensitive recurrent ovarian cancer, perhaps reflecting the biologic heterogeneity and low somatic BRCA mutation rate in breast cancer. The use of PARPi is gradually evolving, including combination strategies with chemotherapy, targeted agents, radiotherapy, or immunotherapy in women with and without gBRCAm. The role of predictive biomarkers, including molecular signatures and homologous recombination repair deficiency scores based on loss of heterozygosity and other structural genomic aberrations, will be crucial to identify a subgroup of patients who may have benefit from PARPi. An improved understanding of the mechanisms underlying PARPi clinical resistance will also be important to enable the development of new approaches to increase efficacy. This is a field rich in opportunity, and the coming years should see a better understanding of which breast cancer patients we should treat with PARPi and where these agents should come in over the course of treatment.
| S-EPMC7430202 | biostudies-literature
Project description:Oxidative and replication stress underlie genomic instability of cancer cells. Amplifying genomic instability through radiotherapy and chemotherapy has been a powerful but nonselective means of killing cancer cells. Precision medicine has revolutionized cancer therapy by putting forth the concept of selective targeting of cancer cells. Poly(ADP-ribose) polymerase (PARP) inhibitors represent a successful example of precision medicine as the first drugs targeting DNA damage response to have entered the clinic. PARP inhibitors act through synthetic lethality with mutations in DNA repair genes and were approved for the treatment of BRCA mutated ovarian and breast cancer. PARP inhibitors destabilize replication forks through PARP DNA entrapment and induce cell death through replication stress-induced mitotic catastrophe. Inhibitors of poly(ADP-ribose) glycohydrolase (PARG) exploit and exacerbate replication deficiencies of cancer cells and may complement PARP inhibitors in targeting a broad range of cancer types with different sources of genomic instability. Here I provide an overview of the molecular mechanisms and cellular consequences of PARP and PARG inhibition. I highlight clinical performance of four PARP inhibitors used in cancer therapy (olaparib, rucaparib, niraparib, and talazoparib) and discuss the predictive biomarkers of inhibitor sensitivity, mechanisms of resistance as well as the means of overcoming them through combination therapy.
| S-EPMC7050487 | biostudies-literature
Project description:Poly(ADP-ribose) polymerase (PARP), which was first described over 50 years ago by Mandel, are a family of protein enzymes involved in DNA damage response and works by recognizing the single-strand DNA break (ssDNA) and then effecting DNA repair. A double-strand DNA (dsDNA) break can be repaired by one of two different pathways: homologous recombination (HR) or non-homologous end joining (NHEJ). Homologous recombination occurs in the G2 or M phase of the cell cycle when a sister chromatid is available to use as a template for repair. Because a template is available, HR is a high fidelity, error-free form of DNA repair. With NHEJ there is not a template and the DNA is trimmed and ligated which is a very error-prone process of repair which can lead to genetic instability. Exploiting these mechanism led to development of PARP inhibitors with the idea of utilizing synthetic lethality, where two deficiencies each having no effect on the cellular outcome become lethal when combined, as single agent in BRCA deficient patients or as chemotherapy/radiotherapy combinations to inhibit ssDNA repair. The recent approval of olaparib in BRCA deficient ovarian cancer patients in US and Europe has opened up a whole new treatment option for ovarian cancer patients. This review will discuss the different PARP inhibitors in development and the potential use of this class of agents in the future.
| S-EPMC4880823 | biostudies-literature
Project description:In our previous studies of the molecular mechanisms of poly(ADP-ribose) polymerase 1 (PARP-1)-mediated transcriptional regulation we identified a novel class of PARP-1 inhibitors targeting the histone-dependent route of PARP-1 activation. Because histone-dependent activation is unique to PARP-1, non-NAD-like PARP-1 inhibitors have the potential to bypass the off-target effects of classical NAD-dependent PARP-1 inhibitors, such as olaparib, veliparib, and rucaparib. Furthermore, our recently published studies demonstrate that, compared to NAD-like PARP-1 inhibitors that are used clinically, the non-NAD-like PARP-1 inhibitor 5F02 exhibited superior antitumor activity in cell and animal models of human prostate cancer (PC). In this study, we further evaluated the antitumor activity of 5F02 and several of its novel analogues against PC cells. In contrast to NAD-like PARP-1 inhibitors, non-NAD-like PARP-1 inhibitors demonstrated efficacy against androgen-dependent and -independent routes of androgen receptor signaling activation. Our experiments reveal that methylation of the quaternary ammonium salt and the presence of esters were critical for the antitumor activity of 5F02 against PC cells. In addition, we examined the role of a related regulatory protein of PARP-1, called Poly(ADP-ribose) glycohydrolase (PARG), in prostate carcinogenesis. Our study reveals that PARG expression is severely disrupted in PC cells, which is associated with decreased integrity and localization of Cajal bodies (CB). Overall, the results of our study strengthen the justification for using non-NAD-like PARP-1 inhibitors as a novel therapeutic strategy for the treatment of advanced prostate cancer.
| S-EPMC6702078 | biostudies-literature
Project description:IntroductionDue to the difficulty of early diagnosis, nearly 70% of ovarian cancer patients are first diagnosed at an advanced stage. Thus, improving current treatment strategies is of great significance for ovarian cancer patients. Fast-developing poly (ADP-ribose) polymerases inhibitors (PARPis) have been beneficial in the treatment of ovarian cancer at different stages of the disease, but PARPis have serious side effects and can result in drug resistance. Using PARPis in combination with other drug therapies could improve the efficacy of PRAPis.In this study, we identified Disulfiram as a potential therapeutic candidate through drug screening and tested its use in combination with PARPis.MethodsCytotoxicity tests and colony formation experiments showed that the combination of Disulfiram and PARPis decreased the viability of ovarian cancer cells.ResultsThe combination of PARPis with Disulfiram also significantly increased the expression of DNA damage index gH2AX and induced more PARP cleavage. In addition, Disulfiram inhibited the expression of genes associated with the DNA damage repair pathway, indicating that Disulfiram functions through the DNA repair pathway.DiscussionBased on these findings, we propose that Disulfiram reinforces PARPis activity in ovarian cancer cells by improving drug sensitivity. The combined use of Disulfiram and PARPis provides a novel treatment strategy for patients with ovarian cancer.
| S-EPMC10151711 | biostudies-literature
Project description:Ovarian cancer is the fifth leading cause of female cancer deaths in the Western world. Significant progress has been made in the treatment of patients with ovarian cancer, however, the majority of patients experience disease recurrence and new therapies are being sought for such patients. Clinical investigation of poly(ADP-ribose) polymerase (PARP) inhibitors for ovarian cancer treatment has demonstrated promising activity in this disease. Here, we review the development of PARP inhibitors and their future role in the treatment of patients with ovarian cancer. Studies of olaparib, the first PARP inhibitor to be approved in Europe and the USA, in patients with recurrent ovarian cancer have demonstrated clinical efficacy with improvements in progression-free survival. In maintenance therapy of platinum-sensitive ovarian cancer there is supporting evidence of clinical benefit from exploratory endpoints that include time to first subsequent treatment and time to second subsequent treatment. Adverse events that should be monitored following treatment with PARP inhibitors include nausea, vomiting, fatigue and anaemia. Based on the evidence presented, patients who will receive the greatest benefit from PARP inhibition are those with platinum-sensitive relapsed ovarian cancer and a BRCA mutation.
| S-EPMC4816268 | biostudies-literature
Project description:The prognosis for metastatic castration-resistant prostate cancer is unfavorable, and although Poly(ADP)-ribose polymerase-1 (PARP-1) inhibitors have shown efficacy in the treatment of androgen-receptor dependent malignancies, the limited number of options present obstacles for patients that are not responsive to these treatments. Here we utilize an integrated screening strategy that combines cellular screening assays, informatics, in silico computational approaches, and dose-response testing for reducing a compound library of confirmed PARP-1 inhibitors. Six hundred and sixty-four validated PARP-1 inhibitors were reduced to 9 small molecules with favorable physicochemical/ADME properties, unique chemical fingerprints, high dissimilarity to existing drugs, few off-target effects, and dose-responsivity in the 1 µmol/L - 20 µmol/L range. The top 9 unique molecules identified by our integrated screening strategy will be selected for further preclinical development including cytotoxicity testing, effects on mitosis, structure-activity relationship, physicochemical/ADME studies, and in vivo testing.
| S-EPMC7186898 | biostudies-literature
Project description:Loss-of-function mutations in BRCA1 and BRCA2 are detected in at least 5% of unselected patients with breast cancer (BC). These BC susceptibility genes encode proteins critical for DNA homologous recombination repair (HRR). This review provides an update on oral poly(ADP-ribose) polymerase (PARP) inhibitors for the treatment of BC. Olaparib and talazoparib are PARP inhibitors approved as monotherapies for deleterious/suspected deleterious germline BRCA-mutated, HER2-negative BC. Olaparib is approved in the USA for metastatic BC and in Europe for locally advanced/metastatic BC. Talazoparib is approved for locally advanced/metastatic BC in the USA and Europe. In phase 3 trials, olaparib and talazoparib monotherapies demonstrated significant progression-free survival benefits compared with chemotherapy. Common toxicities were effectively managed by supportive treatment and dose interruptions/reductions. Veliparib combined with platinum-based chemotherapy has also shown promise for locally advanced/metastatic BC in a phase 3 trial. Differences in efficacy and safety across PARP inhibitors (olaparib, talazoparib, veliparib, niraparib, rucaparib) may relate to differences in potency of PARP trapping on DNA and cytotoxic specificity. PARP inhibitors are being investigated in early BC, in novel combinations, and in patients without germline BRCA mutations, including those with somatic BRCA mutations and other HRR gene mutations. Ongoing phase 2/3 studies include PARP inhibitors combined with immune checkpoint inhibitors for the treatment of triple-negative BC. Wider access to testing for BRCA and other mutations, and to genetic counseling, are required to identify patients who could benefit from PARP inhibitor therapy. The advent of PARP inhibitors has potential benefits for BC treatment beyond the locally advanced/metastatic setting.
| S-EPMC8105250 | biostudies-literature
Project description:Opinion statementUse of poly(ADP-ribose) polymerase (PARP) inhibitors has greatly increased over the past 5 years. With several new Food and Drug Administration (FDA) approvals, three PARP inhibitors have entered into standard of care treatment for epithelial ovarian cancer (including ovarian, fallopian tube, and primary peritoneal cancer). Olaparib and rucaparib currently have indications for treatment of recurrent BRCA mutant ovarian cancer. Olaparib, rucaparib, and niraparib all have indications for maintenance therapy in recurrent platinum-sensitive ovarian cancer after response to platinum-based therapy. In our practice, we use both olaparib and rucaparib in the recurrent setting, and all three PARP inhibitors in the maintenance setting. Choice of which PARP inhibitor to use in either setting is largely based upon baseline laboratory values, number of prior therapies, and presence of a BRCA mutation and/or homologous recombination deficiency (HRD). As (HRD) and other biomarker assessments continue to improve, we anticipate being able to better identify which patients might most benefit from PARP inhibitor therapy in the future. The clinically available PARP inhibitors are currently undergoing extensive investigations in clinical trials. Other newer agents such as talazoparib, veliparib, 2X-121, and CEP-9722 are in earlier stages of development. As more FDA-approved indications for PARP inhibitor therapy in ovarian cancer become available, we anticipate the decision of which PARP inhibitor to use will become increasingly complex.
| S-EPMC8240125 | biostudies-literature
Project description:AbstractDespite representing only 5% of all annual cancer diagnoses in the United States, pancreatic cancer is projected to become the second leading cause of cancer-related death within the next 10 years. Progress in the treatment of advanced pancreatic cancer has been slow. Systemic therapies rely on combination cytotoxic agents, with limited options at progression. Recently, poly(ADP-ribose) polymerase inhibitors have demonstrated clinical activity in patients with advanced pancreatic cancer and pathogenic variants in BRCA1, BRCA2, and PALB2. In this review, we discuss the development of poly(ADP-ribose) polymerase inhibitors in pancreatic cancer, relevant clinical trials, and future directions.
| S-EPMC8682800 | biostudies-literature