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Recent Patents on Anti-cancer Drug... 2018Treatment of Epithelial Ovarian Cancer (EOC), historically based on surgery and platinum doublet chemotherapy, is associated with high risk of relapse and poor prognosis... (Review)
Review
BACKGROUND
Treatment of Epithelial Ovarian Cancer (EOC), historically based on surgery and platinum doublet chemotherapy, is associated with high risk of relapse and poor prognosis for recurrent disease. In this landscape, the innovative treatment with PARP inhibitors (PARPis) demonstrated an outstanding activity in EOC, and is currently changing clinical practice in BRCA mutant patients.
OBJECTIVES
The study aimed to highlight the mechanism of action, pharmacokinetics, clinical activity, indications and current strategies of development of Olaparib, Niraparib, Rucaparib, Talazoparib and Veliparib, the 5 most relevant PARPis.
METHODS
We performed a review on Pubmed using 'ovarian cancer' and the name of each PARPi (PARP inhibitor) discussed in the review as Medical Subject Headings (MeSH) keywords. The same search was performed on "clinicaltrial.gov" to identify ongoing clinical trials and on "google. com/patents" and "uspto.gov" for recent patents exploring PARPIs in ovarian cancer.
RESULTS
Olaparib, Niraparib and Rucaparib are already approved for the treatment of recurrent EOC and their indications are partially overlapping. Talazoparib and Veliparib are promising PARPis, but currently under investigation in early phase trials. Several studies are evaluating PARPis in monotherapy or in associations, in a wide range of settings (i.e. first line, neoadjuvant, platinum-sensitive and resistant disease).
CONCLUSION
PARPis are valuable options in patients with recurrent ovarian cancer with promising activity in different stages of this disease. Further studies are required to better define optimal clinical settings, predictors of response beyond BRCA mutations and strategies to overcome secondary resistance of PARPis therapy in EOC.
Topics: Animals; Antineoplastic Agents; Drug Resistance, Neoplasm; Female; Humans; Ovarian Neoplasms; Phthalazines; Piperazines; Poly(ADP-ribose) Polymerase Inhibitors
PubMed: 29512470
DOI: 10.2174/1574892813666180305165256 -
Targeted Oncology May 2021Loss-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... (Review)
Review
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.
Topics: Breast Neoplasms; Female; Humans; Poly(ADP-ribose) Polymerase Inhibitors
PubMed: 33710534
DOI: 10.1007/s11523-021-00796-4 -
Pharmacological Research Sep 2021Glioblastoma multiforme (GBM) is a WHO grade IV glioma and the most common malignant, primary brain tumor with a 5-year survival of 7.2%. Its highly infiltrative nature,...
Glioblastoma multiforme (GBM) is a WHO grade IV glioma and the most common malignant, primary brain tumor with a 5-year survival of 7.2%. Its highly infiltrative nature, genetic heterogeneity, and protection by the blood brain barrier (BBB) have posed great treatment challenges. The standard treatment for GBMs is surgical resection followed by chemoradiotherapy. The robust DNA repair and self-renewing capabilities of glioblastoma cells and glioma initiating cells (GICs), respectively, promote resistance against all current treatment modalities. Thus, durable GBM management will require the invention of innovative treatment strategies. In this review, we will describe biological and molecular targets for GBM therapy, the current status of pharmacologic therapy, prominent mechanisms of resistance, and new treatment approaches. To date, medical imaging is primarily used to determine the location, size and macroscopic morphology of GBM before, during, and after therapy. In the future, molecular and cellular imaging approaches will more dynamically monitor the expression of molecular targets and/or immune responses in the tumor, thereby enabling more immediate adaptation of tumor-tailored, targeted therapies.
Topics: Animals; Antineoplastic Agents; Brain Neoplasms; Drug Resistance, Neoplasm; Glioblastoma; Humans
PubMed: 34302977
DOI: 10.1016/j.phrs.2021.105780 -
Clinical Cancer Research : An Official... Nov 2019Irinotecan and topotecan have been widely used as anticancer drugs for the past 20 years. Because of their selectivity as topoisomerase I (TOP1) inhibitors that trap... (Review)
Review
Irinotecan and topotecan have been widely used as anticancer drugs for the past 20 years. Because of their selectivity as topoisomerase I (TOP1) inhibitors that trap TOP1 cleavage complexes, camptothecins are also widely used to elucidate the DNA repair pathways associated with DNA-protein cross-links and replication stress. This review summarizes the basic molecular mechanisms of action of TOP1 inhibitors, their current use, and limitations as anticancer agents. We introduce new therapeutic strategies based on novel TOP1 inhibitor chemical scaffolds including the indenoisoquinolines LMP400 (indotecan), LMP776 (indimitecan), and LMP744, and on tumor-targeted delivery TOP1 inhibitors using liposome, PEGylation, and antibody-drug conjugates. We also address how tumor-specific determinants such as homologous recombination defects (HRD and BRCAness) and Schlafen 11 (SLFN11) expression can be used to guide clinical application of TOP1 inhibitors in combination with DNA damage response inhibitors including PARP, ATR, CHEK1, and ATM inhibitors.
Topics: Antineoplastic Combined Chemotherapy Protocols; Benzimidazoles; DNA Topoisomerases, Type I; Humans; Irinotecan; Molecular Targeted Therapy; Neoplasms; Poly(ADP-ribose) Polymerase Inhibitors; Precision Medicine; Topoisomerase I Inhibitors; Topotecan
PubMed: 31227499
DOI: 10.1158/1078-0432.CCR-19-1089 -
The New England Journal of Medicine Dec 2019Data are limited regarding the use of poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors, such as veliparib, in combination with chemotherapy followed by... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Data are limited regarding the use of poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors, such as veliparib, in combination with chemotherapy followed by maintenance as initial treatment in patients with high-grade serous ovarian carcinoma.
METHODS
In an international, phase 3, placebo-controlled trial, we assessed the efficacy of veliparib added to first-line induction chemotherapy with carboplatin and paclitaxel and continued as maintenance monotherapy in patients with previously untreated stage III or IV high-grade serous ovarian carcinoma. Patients were randomly assigned in a 1:1:1 ratio to receive chemotherapy plus placebo followed by placebo maintenance (control), chemotherapy plus veliparib followed by placebo maintenance (veliparib combination only), or chemotherapy plus veliparib followed by veliparib maintenance (veliparib throughout). Cytoreductive surgery could be performed before initiation or after 3 cycles of trial treatment. Combination chemotherapy was 6 cycles, and maintenance therapy was 30 additional cycles. The primary end point was investigator-assessed progression-free survival in the veliparib-throughout group as compared with the control group, analyzed sequentially in the -mutation cohort, the cohort with homologous-recombination deficiency (HRD) (which included the -mutation cohort), and the intention-to-treat population.
RESULTS
A total of 1140 patients underwent randomization. In the -mutation cohort, the median progression-free survival was 34.7 months in the veliparib-throughout group and 22.0 months in the control group (hazard ratio for progression or death, 0.44; 95% confidence interval [CI], 0.28 to 0.68; P<0.001); in the HRD cohort, it was 31.9 months and 20.5 months, respectively (hazard ratio, 0.57; 95 CI, 0.43 to 0.76; P<0.001); and in the intention-to-treat population, it was 23.5 months and 17.3 months (hazard ratio, 0.68; 95% CI, 0.56 to 0.83; P<0.001). Veliparib led to a higher incidence of anemia and thrombocytopenia when combined with chemotherapy as well as of nausea and fatigue overall.
CONCLUSIONS
Across all trial populations, a regimen of carboplatin, paclitaxel, and veliparib induction therapy followed by veliparib maintenance therapy led to significantly longer progression-free survival than carboplatin plus paclitaxel induction therapy alone. The independent value of adding veliparib during induction therapy without veliparib maintenance was less clear. (Funded by AbbVie; VELIA/GOG-3005 ClinicalTrials.gov number, NCT02470585.).
Topics: Administration, Oral; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Benzimidazoles; Carboplatin; Combined Modality Therapy; Cystadenocarcinoma, Serous; Double-Blind Method; Female; Genes, BRCA1; Genes, BRCA2; Humans; Intention to Treat Analysis; Maintenance Chemotherapy; Middle Aged; Mutation; Ovarian Neoplasms; Paclitaxel; Poly(ADP-ribose) Polymerase Inhibitors; Progression-Free Survival; Quality of Life
PubMed: 31562800
DOI: 10.1056/NEJMoa1909707 -
Cancer Research Nov 2012Small-molecule inhibitors of PARP are thought to mediate their antitumor effects as catalytic inhibitors that block repair of DNA single-strand breaks (SSB). However,...
Small-molecule inhibitors of PARP are thought to mediate their antitumor effects as catalytic inhibitors that block repair of DNA single-strand breaks (SSB). However, the mechanism of action of PARP inhibitors with regard to their effects in cancer cells is not fully understood. In this study, we show that PARP inhibitors trap the PARP1 and PARP2 enzymes at damaged DNA. Trapped PARP-DNA complexes were more cytotoxic than unrepaired SSBs caused by PARP inactivation, arguing that PARP inhibitors act in part as poisons that trap PARP enzyme on DNA. Moreover, the potency in trapping PARP differed markedly among inhibitors with niraparib (MK-4827) > olaparib (AZD-2281) >> veliparib (ABT-888), a pattern not correlated with the catalytic inhibitory properties for each drug. We also analyzed repair pathways for PARP-DNA complexes using 30 genetically altered avian DT40 cell lines with preestablished deletions in specific DNA repair genes. This analysis revealed that, in addition to homologous recombination, postreplication repair, the Fanconi anemia pathway, polymerase β, and FEN1 are critical for repairing trapped PARP-DNA complexes. In summary, our study provides a new mechanistic foundation for the rational application of PARP inhibitors in cancer therapy.
Topics: Animals; Antineoplastic Agents; Birds; Cell Line; DNA Repair; Enzyme Inhibitors; Gene Knockout Techniques; Humans; Immunoblotting; Phthalazines; Piperazines; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; RNA, Small Interfering; Transfection
PubMed: 23118055
DOI: 10.1158/0008-5472.CAN-12-2753 -
Annals of Oncology : Official Journal... Sep 2020In recurrent ovarian cancer, poly(ADP-ribose) polymerase (PARP)-inhibiting agents have transformed the treatment of platinum-sensitive disease. New data support use of... (Review)
Review
BACKGROUND
In recurrent ovarian cancer, poly(ADP-ribose) polymerase (PARP)-inhibiting agents have transformed the treatment of platinum-sensitive disease. New data support use of PARP inhibitors earlier in the treatment algorithm.
DESIGN
We review results from recent phase III trials evaluating PARP inhibitors as treatment and/or maintenance therapy for patients with newly diagnosed ovarian cancer. We discuss the efficacy and safety of these agents in the all-comer and biomarker-selected populations studied in clinical trials, and compare the strengths and limitations of the various trial designs. We also consider priorities for future research, with a particular focus on patient selection and future regimens for populations with high unmet need.
RESULTS
Four phase III trials (SOLO-1, PAOLA-1/ENGOT-OV25, PRIMA/ENGOT-OV26 and VELIA/GOG-3005) demonstrated remarkable improvements in progression-free survival with PARP inhibitor therapy (olaparib, niraparib or veliparib) for newly diagnosed ovarian cancer. Differences in trial design (treatment and/or maintenance setting; single agent or combination; bevacizumab or no bevacizumab), patient selection (surgical outcome, biomarker eligibility, prognosis) and primary analysis population (intention-to-treat, BRCA mutated or homologous recombination deficiency positive) affect the conclusions that can be drawn from these trials. Overall survival data are pending and there is limited experience regarding long-term safety.
CONCLUSIONS
PARP inhibitors play a pivotal role in the management of newly diagnosed ovarian cancer, which will affect subsequent treatment choices. Refinement of testing for patient selection and identification of regimens to treat populations that appear to benefit less from PARP inhibitors are a priority.
Topics: Carcinoma, Ovarian Epithelial; Clinical Trials as Topic; Female; Humans; Neoplasm Recurrence, Local; Ovarian Neoplasms; Poly(ADP-ribose) Polymerase Inhibitors
PubMed: 32569725
DOI: 10.1016/j.annonc.2020.06.004 -
Pharmacological Research Jun 2018In women, breast cancer is the most common cancer diagnosis and second most common cause of cancer death. More than half of breast cancer patients will develop... (Review)
Review
In women, breast cancer is the most common cancer diagnosis and second most common cause of cancer death. More than half of breast cancer patients will develop metastases to the bone, liver, lung, or brain. Breast cancer brain metastases (BCBM) confers a poor prognosis, as current therapeutic options of surgery, radiation, and chemotherapy rarely significantly extend life and are considered palliative. Within the realm of chemotherapy, the last decade has seen an explosion of novel chemotherapeutics involving targeting agents and unique dosage forms. We provide a historical overview of BCBM chemotherapy, review the mechanisms of new agents such as poly-ADP ribose polymerase inhibitors, cyclin-dependent kinase 4/6 inhibitors, phosphatidyl inositol 3-kinaseinhibitors, estrogen pathway antagonists for hormone-receptor positive BCBM; tyrosine kinase inhibitors, antibodies, and conjugates for HER2 BCBM; repurposed cytotoxic chemotherapy for triple negative BCBM; and the utilization of these new agents and formulations in ongoing clinical trials. The mechanisms of novel dosage formulations such as nanoparticles, liposomes, pegylation, the concepts of enhanced permeation and retention, and drugs utilizing these concepts involved in clinical trials are also discussed. These new treatments provide a promising outlook in the treatment of BCBM.
Topics: Animals; Antineoplastic Agents; Blood-Brain Barrier; Brain Neoplasms; Breast Neoplasms; Drug Delivery Systems; Humans
PubMed: 29604436
DOI: 10.1016/j.phrs.2018.03.021 -
Cell Nov 2020Strategies for installing authentic ADP-ribosylation (ADPr) at desired positions are fundamental for creating the tools needed to explore this elusive post-translational...
Strategies for installing authentic ADP-ribosylation (ADPr) at desired positions are fundamental for creating the tools needed to explore this elusive post-translational modification (PTM) in essential cellular processes. Here, we describe a phospho-guided chemoenzymatic approach based on the Ser-ADPr writer complex for rapid, scalable preparation of a panel of pure, precisely modified peptides. Integrating this methodology with phage display technology, we have developed site-specific as well as broad-specificity antibodies to mono-ADPr. These recombinant antibodies have been selected and characterized using multiple ADP-ribosylated peptides and tested by immunoblotting and immunofluorescence for their ability to detect physiological ADPr events. Mono-ADPr proteomics and poly-to-mono comparisons at the modification site level have revealed the prevalence of mono-ADPr upon DNA damage and illustrated its dependence on PARG and ARH3. These and future tools created on our versatile chemical biology-recombinant antibody platform have broad potential to elucidate ADPr signaling pathways in health and disease.
Topics: ADP-Ribosylation; Amino Acid Sequence; Antibodies; Benzimidazoles; Carrier Proteins; Cell Line, Tumor; Cell Surface Display Techniques; DNA Damage; Glycoside Hydrolases; Histones; Humans; Nuclear Proteins; Phosphates; Phosphoric Monoester Hydrolases; Phthalazines; Piperazines; Poly (ADP-Ribose) Polymerase-1; Recombinant Proteins; Serine; Tyrosine
PubMed: 33186521
DOI: 10.1016/j.cell.2020.09.055 -
Journal of Experimental & Clinical... Jul 2018The poly ADP ribose polymerase (PARP) inhibitor olaparib has been approved for treating prostate cancer (PCa) with BRCA mutations, and veliparib, another PARP inhibitor,...
BACKGROUND
The poly ADP ribose polymerase (PARP) inhibitor olaparib has been approved for treating prostate cancer (PCa) with BRCA mutations, and veliparib, another PARP inhibitor, is being tested in clinical trials. However, veliparib only showed a moderate anticancer effect, and combination therapy is required for PCa patients. Histone deacetylase (HDAC) inhibitors have been tested to improve the anticancer efficacy of PARP inhibitors for PCa cells, but the exact mechanisms are still elusive.
METHODS
Several types of PCa cells and prostate epithelial cell line RWPE-1 were treated with veliparib or SAHA alone or in combination. Cell viability or clonogenicity was tested with violet crystal assay; cell apoptosis was detected with Annexin V-FITC/PI staining and flow cytometry, and the cleaved PARP was tested with western blot; DNA damage was evaluated by staining the cells with γH2AX antibody, and the DNA damage foci were observed with a fluorescent microscopy, and the level of γH2AX was tested with western blot; the protein levels of UHRF1 and BRCA1 were measured with western blot or cell immunofluorescent staining, and the interaction of UHRF1 and BRCA1 proteins was detected with co-immunoprecipitation when cells were treated with drugs. The antitumor effect of combinational therapy was validated in DU145 xenograft models.
RESULTS
PCa cells showed different sensitivity to veliparib or SAHA. Co-administration of both drugs synergistically decreased cell viability and clonogenicity, and synergistically induced cell apoptosis and DNA damage, while had no detectable toxicity to normal prostate epithelial cells. Mechanistically, veliparib or SAHA alone reduced BRCA1 or UHRF1 protein levels, co-treatment with veliparib and SAHA synergistically reduced BRCA1 protein levels by targeting the UHRF1/BRCA1 protein complex, the depletion of UHRF1 resulted in the degradation of BRCA1 protein, while the elevation of UHRF1 impaired co-treatment-reduced BRCA1 protein levels. Co-administration of both drugs synergistically decreased the growth of xenografts.
CONCLUSIONS
Our studies revealed that the synergistic lethality of HDAC and PARP inhibitors resulted from promoting DNA damage and inhibiting HR DNA damage repair pathways, in particular targeting the UHRF1/BRCA1 protein complex. The synergistic lethality of veliparib and SAHA shows great potential for future PCa clinical trials.
Topics: Animals; Benzimidazoles; DNA Damage; Drug Synergism; Histone Deacetylase Inhibitors; Humans; Male; Mice; Mice, Nude; Poly(ADP-ribose) Polymerase Inhibitors; Prostatic Neoplasms
PubMed: 30012171
DOI: 10.1186/s13046-018-0810-7