PARP Inhibitors in Ovarian Cancer: A Review

Patients with advanced ovarian cancer and their experiences and perceptions of sleep disturbance and fatigue across the treatment trajectory: A qualitative study

OBJECTIVE

Sleep disturbance and fatigue are prevalent among patients with advanced ovarian cancer (OC) and associated with poor health-related quality of life (HRQoL). This study aimed to illustrate the lived experiences of OC patients with sleep disturbance and fatigue and the range of factors that they perceive as contributing to these symptoms.

METHODS

Individual semi-structured interviews were conducted with twenty patients with Stage III and IV OC diagnosed and treated within three years (17/20 receiving treatment). Interview transcripts were analyzed based on emergent themes in the data and study goals.

RESULTS

Participants reported high levels of sleep disturbance and fatigue, which interfered with their cognitive, social, and physical function. The nature of their sleep and fatigue issues varied across the treatment trajectory. The majority (16/20) used chemotherapy as a benchmark to assess their current symptom burden. Fatigue and sleep disturbance were described as more intense and cyclic, with the highest symptom burden immediately following chemotherapy infusions followed by periodic improvement between treatments, whereas symptoms were less intense, but more persistent during maintenance therapy. Participants pursued a variety of strategies to manage symptoms, but fatigue persisted among thirteen of twenty participants. Participants were dissatisfied with providers' lack of communication and recommendations to manage symptoms.

CONCLUSION

Findings underscore that while sleep disturbance and fatigue are intense among participants with OC, the lived experiences of these symptoms are qualitatively distinct at different points during treatment. Participants' dissatisfaction with providers' communication suggests the need for improved screening and scaled interventions for advanced OC patients.

Real-world outcomes in molecular subgroups for patients with advanced or recurrent endometrial cancer treated with platinum-based chemotherapy

OBJECTIVE

There is scarce real-world evidence on patients with advanced/recurrent endometrial cancer treated with platinum-based chemotherapy. We assessed the oncological outcome in groups by molecular classification.

METHODS

This retrospective cohort study included patients with advanced/recurrent endometrial cancer treated with platinum-based chemotherapy after hysterectomy at The Norwegian Radium Hospital, Oslo University Hospital, Norway, between January 2006 and December 2017. Patients were molecularly classified as pathogenic POLE mutated, mismatch repair deficient, p53 abnormal, or no specific molecular profile. Time-to-recurrence and cancer-specific survival were calculated.

RESULTS

We identified 264 advanced-stage patients (stage III/IV) and 96 patients with recurrent disease. The molecular classification was prognostic for time-to-recurrence (p < .0001) and cancer-specific survival (p < .0001) in patients with advanced disease, but the outcome did not differ significantly by molecular groups in recurrent patients. In all molecular groups, patients with stage III disease had longer time-to-recurrence and cancer-specific survival compared to patients with stage IV disease. The worst outcome was observed in patients with p53 abnormal tumors with an HR of 1.57 (95% CI 1.07 to 2.30) for time-to-recurrence and HR of 1.78 (95% CI 1.19 to 2.65) for cancer-specific survival in stage III/IV disease and an HR of 1.45 (95% CI 0.83 to 2.52) for time-to-recurrence and HR of 1.60 (95% CI 0.99 to 2.68) for cancer-specific survival in patients with recurrent disease. The few patients with POLE mutated tumors had favorable outcomes despite the advanced/recurrent disease status.

CONCLUSIONS

Oncological outcomes differ by molecular groups, in particular among patients with advanced disease. Patients with p53 abnormal tumors have the worst outcome, while patients with POLE mutated tumors have favorable outcomes even with recurrent disease. Implementation of the addition of immunotherapy to chemotherapy is expected to lead to substantial improvement of outcome, particularly in patients with mismatch repair deficient advanced/recurrent disease. There is still a high unmet need in advanced/recurrent patients with p53 abnormal and no specific molecular profile tumors.

Germline-Somatic Interactions in BRCA-Associated Cancers: Unique Molecular Profiles and Clinical Outcomes Linking ATM to TP53 Synthetic Essentiality

PURPOSE

Germline alterations in homologous recombination repair (gHRR) genes affect the pathogenesis, treatment options, and survival of patients with cancer. However, distinct gHRR gene alterations may differentially affect treatment response and oncogenic signaling. In this study, we interrogated genomic and transcriptomic data and assessed clinical outcomes of patients with gHRR mutations across four BRCA-associated cancers (breast, ovarian, pancreatic, and prostate cancers) to identify therapeutic vulnerabilities.

EXPERIMENTAL DESIGN

We assessed 24,309 patients undergoing matched tumor/normal next-generation DNA and RNA sequencing. Annotated gHRR gene variants [germline BRCA1, germline BRCA2, germline PALB2, germline ATM (gATM), and germline CHEK2] were analyzed. HRs were used to assess survival outcomes comparing germline versus sporadic groups. Somatic alterations and their frequencies were compared across gHRR-altered groups. Differential gene expression and gene set enrichment analysis were used to compare transcriptomic profiles.

RESULTS

Somatic TP53 mutations were depleted in gATM carriers (P < 0.05) across all four BRCA-associated cancers by up to 2.5-fold. Tumors with germline BRCA1/2 mutations were associated with improved survival in patients with ovarian cancer and had consistent enrichment of TP53 mutations in all four cancers. gATM mutations displayed elevated p53 transcriptional activity in all four cancers, with significance reached in breast and prostate cancers (P < 0.01). In breast, ovarian, and prostate cancers, gATM tumors demonstrated significantly increased inflammatory pathways (P < 0.001). Finally, using gene dependency data, we found that cell lines that were highly dependent on ATM were co-dependent on canonical p53 function.

CONCLUSIONS

gATM-associated cancers seem to require intact p53 activity and this synthetic essentiality may be used to guide targeted therapies that perturb canonical TP53 function.

PARP Inhibitors in the Neoadjuvant Setting; A Comprehensive Overview of the Rationale for their Use, Past and Ongoing Clinical Trials

PURPOSEOF REVIEW

Poly (ADP-ribose) polymerases (PARPs) are enzymes essential for detecting and repairing DNA damage through poly-ADP-ribosylation. In cancer, cells with deficiencies in homologous recombination repair mechanisms often become more dependent on PARP-mediated repair mechanisms to effectively repair dsDNA breaks. As such, PARP inhibitors (PARPis) were introduced into clinical practice, serving as a key targeted therapy option through synthetic lethality in the treatment of cancers with homologous recombination repair deficiency (HRD). Though PARPis are currently approved in the adjuvant setting for several cancer types such as ovarian, breast, prostate and pancreatic cancer, their potential role in the neoadjuvant setting remains under investigation. This review outlines the rationale for using PARPi in the neoadjuvant setting and evaluates findings from early and ongoing clinical trials.

RECENT FINDINGS

Our analysis indicates that numerous studies have explored PARPi as a neoadjuvant treatment for HRD-related cancers. The majority of neoadjuvant PARPi trials have been performed in breast and ovarian cancer, while phase II/III evidence supporting efficacy in prostate and pancreatic cancers remains limited. Studies are investigating PARPi in the neoadjuvant setting of HRD-related cancers. Future research should prioritize combination strategies with immune checkpoint inhibitors and expand outcome measures to include patient satisfaction and quality-of-life metrics.

A necrosis inducer promotes an immunogenic response and destroys ovarian cancers in mouse xenografts and patient ascites organoids

Most ovarian cancer patients present with advanced disease and there are few targeted therapies; consequently, five-year survival for ovarian cancer remains below 50%. We described the anticipatory unfolded protein response (a-UPR) hyperactivator, ErSO, which induced profound and often complete regression of breast cancer in mouse models. Here we explore the effectiveness of ErSO against ovarian cancer. ErSO induced death of human PEO4 and Caov-3 ovarian cancer cells in vitro. In mouse xenografts, injected ErSO induced rapid complete, or near complete, regression of orthotopic metastatic PEO4 tumors and of Caov-3 ovarian tumors. Ovarian cancer patients often develop malignant ascites containing ovarian cancer organoids that drive metastasis. ErSO showed activity against 7/7 fresh patient derived ascites organoids (PDAOs). Low nanomolar ErSO destroyed 2/7 PDAOs. ErSO-mediated cell death in PDAOs occurred through the same a-UPR activation mechanism seen in cell culture. Moreover, ErSO family compound-induced a-UPR activation in ovarian cancer cells triggers necrotic cell death and release of damage associated molecular patterns (DAMPs), which strongly activated human macrophage and induced monocyte migration. These studies suggest ErSO has unusual potential for treatment of advanced ovarian cancer.

Maintenance olaparib monotherapy in patients with platinum-sensitive relapsed ovarian cancer without a germline BRCA1 and/or BRCA2 mutation: Final overall survival results from the OPINION trial

OBJECTIVE

Maintenance olaparib demonstrated clinical activity for progression-free survival in patients without a germline BRCA1 and/or BRCA2 mutation (non-gBRCAm) who had platinum-sensitive relapsed ovarian cancer in the phase IIIb, open-label, single-arm, non-comparator, international OPINION trial (NCT03402841). We report final overall survival (OS; secondary endpoint), prespecified secondary endpoint updates and ad hoc OS analysis by homologous recombination deficiency (HRD) and somatic BRCAm (sBRCAm) status.

METHODS

Patients with non-gBRCAm platinum-sensitive relapsed ovarian cancer, ≥2 prior lines of platinum-based chemotherapy, and in response following their last platinum-based chemotherapy received 300 mg olaparib tablets twice daily until disease progression or unacceptable toxicity.

RESULTS

279 patients were enrolled and treated. With a median follow-up in patients censored for OS of 33.1 months (data cut-off September 17, 2021), median OS was 32.7 months (95 % CI 29.5-35.3); the 24-month OS rate was 65.8 %. In ad hoc subgroup analyses, OS rates tended to be higher in patients with HRD-positive tumors; 24-month OS rates were 81.5 %, 74.2 %, 72.0 % and 55.8 % in the sBRCAm, HRD-positive including sBRCAm, HRD-positive excluding sBRCAm, and HRD-negative subgroups, respectively. Grade ≥ 3 treatment-emergent adverse events were reported in 82 patients (29.4 %), most commonly anemia (13.6 %). Overall, two cases of myelodysplastic syndrome were reported (no new cases since the primary analysis).

CONCLUSION

These data provide additional evidence of olaparib as maintenance therapy in patients with non-gBRCAm platinum-sensitive relapsed ovarian cancer, with longer OS observed in those with HRD-positive tumors. The safety profile was consistent with the primary analysis and known safety profile of olaparib, with no new safety findings.

Exploring the Genetic and Clinical Landscape of Dedifferentiated Endometrioid Carcinoma

Dedifferentiated endometrioid carcinoma (DDEC) is rare, has a poor prognosis, and the genes responsible for dedifferentiation remain unclear. This study aimed to clarify the characteristics of DDEC in Japanese patients and develop treatment strategies. Eighteen DDEC cases were included; their clinicopathological features and prognoses were analyzed and compared to those of other histological subtypes. The samples were divided into well-differentiated and undifferentiated components; immunostaining and whole-exome sequencing (n = 3 cases) were conducted. The incidence of DDEC was 2.0% among endometrial cancers. The 5-year progression-free survival and the 5-year overall survival for DDEC was approximately 40% and 30%, respectively. Immunohistochemistry showed that 66.7% of patients were mismatch repair deficient. The rate of p53 mutations was higher than that reported in previous studies, and patients with p53 mutations in the undifferentiated components had a poor prognosis. Whole-exome sequencing revealed different gene mutations and mutation signatures between well-differentiated and undifferentiated components. New genetic mutations in undifferentiated regions were uncommon in all three cases. One case (case 1) exhibited homologous recombination deficiency, whereas the other two showed microsatellite instability-high and hypermutator phenotypes. Genetic analysis suggests that immune checkpoint and poly (ADP-ribose) polymerase inhibitors and drugs targeting the p53 pathway may be effective against DDEC.

Ovarian cancer survival by residual disease following cytoreductive surgery: a nationwide study in Norway

BACKGROUND

Residual disease (RD) following cytoreductive surgery is prognostic for epithelial ovarian cancer (EOC) patients. Few studies have evaluated RD and survival by tumor histotype and across continuous RD diameter.

METHODS

2608 individuals with stages III-IV invasive EOC diagnosed between 2013 and 2022 were identified using the Cancer Registry of Norway. In flexible parametric models, we compared excess mortality comparing RD versus no macroscopic residual disease (NMRD); systemic anti-cancer therapy was evaluated in a sub-cohort from 2019. Excess mortality was assessed across continuous RD size using restricted cubic splines.

RESULTS

Among 1849 patients with cytoreductive surgery, survival was worse for individuals with RD (vs. NMRD), excess hazard ratio (EHR) = 2.62 (95% confidence interval = (2.27-3.01)); no heterogeneity was observed by histotype (p = 0.21). Patients with 0.1-0.4 cm RD had 2-fold higher risk of death (EHR = 2.09 (1.63-2.68)) relative to women with NMRD; ~3-fold higher risk was observed for all other categories (e.g., 0.5-0.9 cm, EHR = 2.97 (2.26-3.89); 3.0-20 cm, 2.75 (2.05-3.70)). No significant difference in three-year survival was observed across continuous RD diameter (p ≥ 0.17). NMRD was associated with better survival regardless of neoadjuvant chemotherapy.

DISCUSSION

Achieving NMRD resulted in the best survival outcomes. Among patients with RD, we observed no significant difference in survival by RD diameter.

Clinical differences among the PARP inhibitors in the first-line treatment of advanced-stage ovarian carcinoma

INTRODUCTION

Despite favorable patient response rates to first-line chemotherapy, 5-year overall survival rates in ovarian cancer are dismal. Fortunately, the inclusion of PARP inhibitors (e.g. olaparib, niraparib, and rucaparib) following the completion of primary induction chemotherapy, has conferred improved progression-free survival rates.

AREAS COVERED

There are treatment outcome differences among the various PARP inhibitors that coincide with a patient's specific homologous recombination deficit (HRD) status; moreover, only single-agent olaparib and olaparib with bevacizumab have conferred a 5-year overall survival benefit. In the current review, we recount the clinical differences associated with the available PARP inhibitors in the management of advanced-stage ovarian carcinoma.

EXPERT OPINION

The inclusion of PARP inhibitors has significantly improved survival benefits in advanced-stage ovarian cancer, especially among patients with an identifiable HRD. While there are tolerability differences inherent to the specific PARP inhibitors, not to mention approval distinctions, olaparib is the only PARP inhibitor that has demonstrated consistent overall survival benefits.

Population Pharmacokinetic Modeling of Total and Unbound Pamiparib in Glioblastoma Patients: Insights into Drug Disposition and Dosing Optimization

Background: This study aimed to develop a population pharmacokinetic (PK) model that characterized the plasma concentration-time profiles of the total and unbound pamiparib, a PARP inhibitor, in glioblastoma patients and identified patient factors influencing the PK. Methods: The total and unbound pamiparib plasma concentration data were obtained from 41 glioblastoma patients receiving 60 mg of pamiparib twice daily. Nonlinear mixed-effects modeling was performed using Monolix (2024R1) to simultaneously fit the total and unbound drug plasma concentration data. The covariate model was developed by covariate screening using generalized additive modeling followed by stepwise covariate modeling. Model simulations were performed following oral doses of 10-60 mg BID. Results: The total and unbound pamiparib plasma concentration-time profiles were best described by a one-compartment model with first-order absorption and elimination. Creatinine clearance and age were the significant covariates on the apparent volume of distribution (V/F) and apparent clearance (CL/F), respectively, explaining ~22% and ~5% of IIV of V/F and CL/F. Population estimates of the absorption rate constant (Ka), V/F, CL/F, and unbound fraction for the total drug were 1.58 h-1, 44 L, 2.59 L/h, and 0.041. Model simulations suggested that doses as low as 20 mg BID may be adequate for therapeutic effects in a general patient population, assuming that a target engagement ratio (i.e., unbound Css,min/IC50) of 5 or above is sufficient for full target engagement. Conclusions: The total and unbound pamiparib plasma PK are well characterized by a linear one-compartment model, with creatinine clearance as the significant covariate on V/F. Model simulations support further clinical investigation into dose reduction to optimize the benefit-to-risk ratio of pamiparib, particularly in combination therapies.

LIG1 Is a Synthetic Lethal Target in BRCA1 Mutant Cancers

Synthetic lethality approaches in BRCA1/2-mutated cancers have focused on PARP inhibitors, which are subject to high rates of innate or acquired resistance in patients. In this study, we used CRISPR/Cas9-based screening to identify DNA ligase I (LIG1) as a novel target for synthetic lethality in BRCA1-mutated cancers. Publicly available data supported LIG1 hyperdependence of BRCA1 mutant cells across a variety of breast and ovarian cancer cell lines. We used CRISPRn, CRISPRi, RNAi, and protein degradation to confirm the lethal effect of LIG1 inactivation at the DNA, RNA, and protein level in BRCA1 mutant cells in vitro. LIG1 inactivation resulted in viability loss across multiple BRCA1-mutated cell lines, whereas no effect was observed in BRCA1/2 wild-type cell lines, demonstrating target selectivity for the BRCA1 mutant context. On-target nature of the phenotype was demonstrated through rescue of viability with exogenous wild-type LIG1 cDNA. Next, we demonstrated a concentration-dependent relationship of LIG1 protein expression and BRCA1 mutant cell viability using a titratable, degradable LIG1 fusion protein. BRCA1 mutant viability required LIG1 catalytic activity, as catalytically dead mutant LIG1K568A failed to rescue viability loss caused by endogenous LIG1 depletion. LIG1 perturbation produced proportional increases in PAR staining in BRCA1 mutant cells, indicating a mechanism consistent with the function of LIG1 in sealing ssDNA nicks. Finally, we confirmed LIG1 hyperdependence in vivo using a xenograft model in which LIG1 loss resulted in tumor stasis in all mice. Our cumulative findings demonstrate that LIG1 is a promising synthetic lethal target for development in patients with BRCA1-mutant cancers.

KPNA5 Suppresses Malignant Progression of Ovarian Cancer Through Importing the PTPN4 Into the Nucleus

BACKGROUND

Abnormal protein localization due to disrupted nucleoplasmic transport is common in tumor cells, but its mechanisms are not well understood. Nuclear pore complexes and nuclear transporter proteins are crucial for protein transport between the nucleus and cytoplasm. Evidence increasingly shows that abnormal expression of karyopherin family proteins disrupts protein translocation, affecting processes like cell differentiation, proliferation, apoptosis, and transcriptional regulation. However, their functions and roles in ovarian cancer remain unclear.

METHODS

The expression level of KPNA5 in ovarian cancer tissues and cells was detected by IHC, Western blot, and qPCR. CCK-8 and colony formation assays were used to assess cell proliferation ability. Transwell assay was conducted to determine cell migration and invasion capacity. A xenograft model was used to assess the effect of KPNA5 on tumor growth in vivo.

RESULTS

KPNA5 expression is downregulated in ovarian cancer (OC) tissues. Low KPNA5 levels were associated with poor survival in OC patients, validated by an OC tissue sample cohort. Overexpression of KPNA5 significantly suppressed OC cell proliferation, tumor growth, and invasion in both in vitro and in vivo studies. Mechanistically, KPNA5 recognizes nuclear localization signals (NLSs) in PTPN4, mediating its nuclear transport and inhibiting STAT3 phosphorylation and its downstream signaling pathway. Similarly, PTPN4 overexpression reduced OC cell viability and invasion, also suppressing STAT3 phosphorylation.

CONCLUSIONS

Our findings identify KPNA5 as a tumor suppressor in OC, presenting a potential therapeutic target for OC treatment.

Dual targeting of Aurora Kinase A and poly (ADP-ribose) polymerase as a therapeutic option for patients with ovarian cancer: preclinical evaluations

PURPOSE

Epithelial ovarian cancers (EOCs) are often diagnosed at an advanced stage, leading to poor survival outcomes despite chemotherapeutic and surgical advances. Precision oncology strategies have been developed to treat EOCs characterized by BRCA1 and BRCA2 inactivation with consequent homologous recombination (HR) repair defects. HR deficiency enhances tumor sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis), approved for EOCs as maintenance therapy, although they have been discontinued as recurrent EOC monotherapy. However, combination treatment with PARPis may be a viable alternate strategy for EOCs. Moreover, EOC patients with wild-type BRCA are ineligible for PARPs, necessitating novel approaches. We previously discovered that inhibiting Aurora kinase A (AURKA) downregulates PARP and BRCA1/2 expression in EOCs and may constitute a viable approach for EOCs.

METHODS

Herein, we evaluated combined PARPi olaparib with the selective AURKA inhibitor (AURKAi) VIC-1911 in six different patient-derived xenograft (PDX) EOC models, including two with mutant BRCA1, two with mutant BRCA2, one with mutant BRCA1/2, and one with wild-type BRCA1/2.

RESULTS

We found that combined olaparib + VIC-1911 treatment reduced tumor volumes and weights by up 90% in some PDX models, with synergistic effect compared to olaparib and VIC-1911 monotherapy. Additionally, combined olaparib + VIC-1911 treatment improved survival of mice harboring both mutant BRCA1 and wild-type BRCA1/2 PDXs. Generally, mice tolerated the drug combinations well during treatment, though loss of body weight was observed at higher drug dosages and with intensive treatment regimens.

CONCLUSION

Our studies indicate a synergistic benefit from combined PARPi and AURKAi in mutant and wild-type BRCA EOC tumors.

EM-12, a natural sesquiterpene lactone extracted from Elephantopus mollis, promotes cancer cell apoptosis by activating ER stress

The Elephantopus mollis H.B.K. contains various sesquiterpene lactones that have shown anti-proliferative and proapoptotic effects in various cancers, although the underlying mechanisms are partially understood. Inducing of excessive ER stress is a potential cancer therapeutic strategy. However, ER stress activator remain limited in current clinical applications. In this study, we identified that EM-12, an uncovered sesquiterpene lactone isolated from Elephantopus mollis H.B.K., as a BiP ATPase activity inhibitor through BiP ATPase activity assay in vitro. This molecule also exhibits significantly greater cytotoxicity in numerous ovarian cancer cell lines, including paclitaxel-resistance ovarian cancer cell line, compared to transformed ovarian epithelial cell lines. In addition, EM-12 exerts broad-spectrum cytotoxicity against various human cancer cell lines, including liver, nasopharyngeal, and breast cancer cell lines. Mechanically, EM-12 promotes ER stress and ER-stress-related apoptosis to against cancer cells through inhibiting BiP ATPase activity.

PARylation-mediated post-transcriptional modifications in cancer immunity and immunotherapy

Poly-ADP-ribosylation (PARylation) is a post-translational modification in which ADP-ribose is added to substrate proteins. PARylation is mediated by a superfamily of ADP-ribosyl transferases known as PARPs and influences a wide range of cellular functions, including genome integrity maintenance, and the regulation of proliferation and differentiation. We and others have recently reported that PARylation of SH3 domain-binding protein 2 (3BP2) plays a role in bone metabolism, immune system regulation, and cytokine production. Additionally, PARylation has recently gained attention as a target for cancer treatment. In this review, we provide an overview of PARylation, its involvement in several signaling pathways related to cancer immunity, and the potential of combination therapies with PARP inhibitors and immune checkpoint inhibitors.

A Rapid and Reliable Test for BRCA1 Promoter Hypermethylation in Paraffin Tissue Using Pyrosequencing

Background: Ovarian cancers harboring inactivating mutations in BRCA1 or BRCA2 demonstrate increased sensitivity to poly (ADP-ribose) polymerase inhibitors (PARPis). BRCA1 promoter methylation could serve as a more precise biomarker for therapy response, as it reflects a dynamic mechanism, compared with genomic scarring, which remains persistent and lacks real-time prediction of sensitivity after prior lines of treatment. Additionally, the BRCA1 promoter methylation may provide a more precise biomarker for identifying homologous recombination deficiency compared to genomic scars. In this study, we describe the validation of a pyrosequencing method to assess BRCA1 promoter methylation status. Methods: Tumor DNA from high-grade serous ovarian carcinoma was tested targeting 11 CpG sites adjacent to the BRCA1 transcription start site. All cases had concordant results compared with TCGA methylation data or real-time PCR results. To determine the sensitivity of this assay, we performed a dilution series experiment using seven mixtures of methylated DNA and unmethylated genomic DNA (100%, 50%, 25%, 12.5%, 6.25%, 3.125%, and 1.56%). Results: We observed a high degree of correlation (R2 = 0.9945) between predicted and observed results. Intra- and inter-run reproducibility was established by performing six cases in triplicate in the same run and in three different runs. Conclusions: By applying 10% as the cutoff for detection of methylation, the PyroMark Q24 pyrosequencing assay demonstrated 100% concordance across all the ovarian cancer cases included in this validation. This assay has been approved by the New York State Department of Health as a laboratory-specific assay for clinical use.

Niraparib Maintenance Therapy in Patients with Platinum-Sensitive Recurrent Ovarian Cancer: Real-World Experience at Hospitals in Spain

BACKGROUND

The reported benefit of poly (ADP-ribose) polymerase inhibitor (PARPi) maintenance in patients with newly diagnosed and platinum (Pt)-sensitive recurrent ovarian cancer (OC) included in randomized clinical trials needs to be corroborated in a less selected population.

OBJECTIVE

The aim is to increase the evidence on niraparib in a real-world setting.

METHODS

This is a retrospective observational study including women with platinum-sensitive relapsed high-grade serous OC who started niraparib maintenance between August 2019 (marketing data, Spain) and May 2022. Patients received ≥ 2 previous lines of therapy with complete or partial response to prior chemotherapy. Patient characteristics, niraparib dose, adequacy of dose individualization, effectiveness (progression-free survival [PFS] and overall survival), safety, and economic savings with an individualized starting dose (ISD) strategy were assessed.

RESULTS

The study included 217 patients with a median of 8.9 months of niraparib duration: breast cancer gene (BRCA) wild-type OC, 70%; two prior treatment lines, 49%; Research on Adverse Drug Events and Reports (RADAR) criteria, 82% (receiving mainly 200 mg of niraparib, 79%). Median PFS was 10.8 months (95% confidence interval [CI], 8.4-14.8) without statistically significant differences based on starting dose strategy, contrary to what was observed on the basis of prior lines, response to prior chemotherapy, BRCA mutational status, and International Federation of Gynecology and Obstetrics (FIGO) stage at diagnosis. The last three variables also showed a statistically significant predictive prognostic value for effectiveness. Dose interruptions due to toxicity were required in 7% of patients, and dose adjustments in 56% were mainly due to hematologic toxicities. The actual dose of niraparib reveals economic savings versus the theoretical cost.

CONCLUSION

This large real-world analysis corroborates the tolerability and activity of niraparib maintenance for platinum-sensitive recurrent OC and economic savings.

The efficacy and safety of mirvetuximab soravtansine in FRα-positive, third-line and later, recurrent platinum-sensitive ovarian cancer: the single-arm phase II PICCOLO trial

BACKGROUND

Mirvetuximab soravtansine-gynx (MIRV) is a first-in-class, folate receptor alpha (FRα)-targeting antibody-drug conjugate with United States Food and Drug Administration approval for FRα-positive platinum-resistant ovarian cancer. PICCOLO is a phase II, global, open-label, single-arm trial of MIRV as third-line or greater (≥3L) treatment in patients with FRα-positive (≥75% of cells with ≥2+ staining intensity) recurrent platinum-sensitive ovarian cancer (PSOC).

PATIENTS AND METHODS

Participants received MIRV (6 mg/kg adjusted ideal body weight every 3 weeks) until progressive disease (PD), unacceptable toxicity, withdrawal of consent, or death. Primary endpoint was investigator-assessed objective response rate (ORR). Key secondary endpoint was investigator-assessed duration of response (DOR). Additional endpoints included investigator-assessed progression-free survival (PFS), overall survival (OS), and safety. Analyses of subgroups by disease characteristics (e.g. platinum-free interval) and treatment history [e.g. prior bevacizumab and poly (adenosine diphosphate [ADP]-ribose) polymerase inhibitor (PARPi) treatment] were exploratory.

RESULTS

Seventy-nine participants were enrolled and efficacy assessable. The primary endpoint was met; ORR was 51.9% [95% confidence interval (CI) 40.4% to 63.3%]. Median DOR was 8.25 months (95% CI 5.55-10.78 months) and median PFS was 6.93 months (95% CI 5.85-9.59 months). OS was not mature at data cut-off. ORR was 45.8% (95% CI 32.7% to 59.2%) in participants with PD while on/within 30 days of prior PARPi (n = 59) and 60.0% (95% CI 14.7% to 94.7%) in those without PD with prior PARPi (n = 5). No new safety signals occurred; most common treatment-emergent adverse events (TEAEs) were gastrointestinal, neurosensory, and resolvable ocular events. TEAEs led to discontinuation in 13 participants (16%) and death in 2 participants (3%).

CONCLUSIONS

MIRV as ≥3L treatment in heavily pretreated recurrent FRα-positive PSOC demonstrated notable efficacy and tolerable safety, including among those with prior PD on or within 30 days of PARPi (NCT05041257).

A Novel Insight into the Role of Obesity-Related Adipokines in Ovarian Cancer-State-of-the-Art Review and Future Perspectives

Ovarian cancer (OC) is one of the most fatal gynecological neoplasms. Meta-analyses have shown that the relationship between body mass index (BMI) and ovarian cancer incidence was detected in some types of ovarian cancer. Chronic inflammation and excessive accumulation of free fatty acids are key adipose tissue-derived factors initiating cancer development. Cancer cells transform adipose-derived stem cells into cancer-associated adipocytes, which produce adipokines and interleukins. It was revealed that adipokines exert a pleiotropic role in ovarian cancer pathogenesis. Chemerin presents both pro-cancer and anti-cancer action in ovarian cancer development. Chemerin induces angiogenesis and increases programmed death ligand-1 (PD-L1) expression, leading to enhanced proliferation and migration of OC cells. Apelin impacts cancer cell migration and acts as a mitogenic factor. Moreover, apelin exerts influence on lipid uptake into cancer cells and accelerates fatty acid oxidation, which provides energy for cancer cells. Visfatin induces matrix metallopeptidase 2 (MMP2) expression involved in extracellular matrix degradation and suppresses claudin 3 and 4 expression. Visfatin also induces a shift to anaerobic glucose metabolism and influences poly-ADP ribose polymerase (PARP). Resistin induces MMP2 and vascular endothelial growth factor (VEGF) expression and contributes to cisplatin-resistance development. A substantial body of evidence indicates that antagonists of adipokines mitigate OC progression, and adipokines are gaining gradual recognition as a potential therapeutic aim in ovarian cancer targeted therapy.

Real-world duration of first-line maintenance niraparib monotherapy in patients with epithelial ovarian cancer in the United States: the CHAR1ZMA study

OBJECTIVE

The CHAR1ZMA study described real-world duration of first-line maintenance niraparib monotherapy among patients with epithelial ovarian cancer.

METHODS

This retrospective study used a US nationwide, electronic-health-record-derived, de-identified database. Eligible patients were aged ≥18 years with epithelial ovarian cancer who initiated first-line maintenance niraparib monotherapy (January 2017-December 2022 [inclusive]) following first-line platinum-based chemotherapy. Niraparib monotherapy duration was measured as the time to treatment discontinuation, estimated using Kaplan-Meier methodology, overall and stratified by treatment duration (early discontinuers [≤90 days]; non-early discontinuers [>90 days or did not discontinue]). Analyses were repeated in a sub-group of patients with homologous recombination-deficient tumors.

RESULTS

Toxicity was the most common reason for niraparib discontinuation among early discontinuers (67.7%) and was less frequent among non-early discontinuers (18.1%). Dose modifications were less frequent among early discontinuers (29.8%) than non-early discontinuers (53.6%). Disease progression was the most common reason for niraparib discontinuation among non-early discontinuers (74.8%) and was less frequent among early discontinuers (30.4%). The observed median treatment duration was 7.2 months (95% CI 6.0 to 8.1) overall (N = 560) and was 4.5 months longer among non-early discontinuers (11.7 months [95% CI 9.8 to 14.7]; n = 399). In the homologous recombination-deficient sub-group (n = 144), the observed median treatment duration was 11.6 months (95% CI 7.8. to 16.1) and was 5.1 months longer among non-early discontinuers (16.7 months [95% CI 12.0 to 22.8]; n = 114).

CONCLUSION

In this real-world study of patients with epithelial ovarian cancer receiving first-line maintenance niraparib monotherapy, drug toxicity was the most common reason for treatment discontinuation in early discontinuers. Effective and early clinical management of drug toxicity may help mitigate these adverse events, allowing patients to remain on niraparib maintenance treatment longer and experience the potential full therapeutic benefit.

Unlocking the future: mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

Background

Mitochondrial genes are involved in the tumor metabolism of ovarian cancer (OC), affecting immune cell infiltration and treatment response. We aimed to utilize mitochondrial genes to predict OC prognosis and immunotherapy response.

Methods

The prognosis data, immunotherapy efficacy and next generation sequencing data of OC patients were downloaded from The Cancer Genome Atlas Program (TCGA) and Gene Expression Omnibus (GEO). Mitochondrial genes were sourced from the MitoCarta3.0 database. Seventy percent of the patients were randomly selected as the discovery cohort for model construction, while the remaining 30% constituted the validation cohort for model assessment. Using the expression of mitochondrial genes as the predictor variable and based on the neural network algorithm, the overall survival (OS) time and immunotherapy efficacy (complete or partial response) of the included patients were predicted.

Results

There were 375 OC patients included to construct the prognostic model, and 26 patients were included to construct the immune efficacy model. The average area under the receiver operating characteristic curve (AUC) of the prognostic model was: 0.7268 [95% confidence interval (CI), 0.7258-0.7278] in the discovery cohort and 0.6475 (95% CI: 0.6466-0.6484) in the validation cohort. The average AUC of the immunotherapy efficacy model was: 0.9444 (95% CI: 0.8333-1.0000) in the discovery cohort and 0.9167 (95% CI: 0.6667-1.0000) in the validation cohort.

Conclusions

The application of mitochondrial genes and neural networks shows potential in predicting the prognosis and immunotherapy response in OC patients. And this approach could provide valuable insights for personalized treatment strategies.

A comprehensive comparison of PARP inhibitors as maintenance therapy in platinum-sensitive recurrent ovarian cancer: a systematic review and network meta-analysis

BACKGROUND

PARP inhibitors (PARPis) have shown promising effectiveness for ovarian cancer. This network meta-analysis (PROSPERO registration number CRD42024503390) comprehensively evaluated the effectiveness and safety of PARPis in platinum-sensitive recurrent ovarian cancer (PSROC).

METHODS

Articles published before January 6, 2024 were obtained from electronic databases. The study assessed and compared survival outcomes including overall survival (OS), progression-free survival (PFS), second progression-free survival (PFS2), time to first subsequent treatment (TFST), time to second subsequent treatment (TSST), and chemotherapy-free interval (CFI). Additionally, safety outcomes were investigated, specifically focusing on grade 3-4 treatment-emergent adverse effects (TEAEs). The evaluation of OS and PFS was also conducted based on the BRCA and HRD (homologous recombination deficiency) statuses.

RESULTS

Six randomized controlled trials were examined and the four PARPis (olaparib, niraparib, rucaparib and fuluzolparib) have been found to significantly increase the PFS in entire population as well as in subgroups of HRD and BRCAm (BRCA mutation). Only olaparib demonstrated a substantial improvement in OS compared to placebo in entire population (hazard ratio [HR] 0.73; 95% confidence interval [CI] 0.60-0.90), as well as in the subgroup of BRCAm. All analyzed PARPis had significant efficacy in prolonging PFS2, TFST, TSST and CFI. For safety concerns, PARPis could significantly increase incidence of TEAEs (grade3-4), while olaparib had least haematological TEAEs (grade3-4) events compared to other PARPis.

CONCLUSION

All included PARPis showed various degrees of benefit in survival outcomes and safety profile was acceptable for PSROC patients. Among them olaparib had the best performance in both efficacy and safety.

Unlocking the future: Mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

BACKGROUND

Mitochondrial genes are involved in tumor metabolism in ovarian cancer (OC) and affect immune cell infiltration and treatment responses.

AIM

To predict prognosis and immunotherapy response in patients diagnosed with OC using mitochondrial genes and neural networks.

METHODS

Prognosis, immunotherapy efficacy, and next-generation sequencing data of patients with OC were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus. Mitochondrial genes were sourced from the MitoCarta3.0 database. The discovery cohort for model construction was created from 70% of the patients, whereas the remaining 30% constituted the validation cohort. Using the expression of mitochondrial genes as the predictor variable and based on neural network algorithm, the overall survival time and immunotherapy efficacy (complete or partial response) of patients were predicted.

RESULTS

In total, 375 patients with OC were included to construct the prognostic model, and 26 patients were included to construct the immune efficacy model. The average area under the receiver operating characteristic curve of the prognostic model was 0.7268 [95% confidence interval (CI): 0.7258-0.7278] in the discovery cohort and 0.6475 (95%CI: 0.6466-0.6484) in the validation cohort. The average area under the receiver operating characteristic curve of the immunotherapy efficacy model was 0.9444 (95%CI: 0.8333-1.0000) in the discovery cohort and 0.9167 (95%CI: 0.6667-1.0000) in the validation cohort.

CONCLUSION

The application of mitochondrial genes and neural networks has the potential to predict prognosis and immunotherapy response in patients with OC, providing valuable insights into personalized treatment strategies.

Promising new drugs and therapeutic approaches for treatment of ovarian cancer-targeting the hallmarks of cancer

Ovarian cancer remains the most lethal gynecological malignancy. Despite the approval of promising targeted therapy such as bevacizumab and PARP inhibitors, 5-year survival has not improved significantly. Thus, there is an urgent need for new therapeutics. New advancements in therapeutic strategies target the pivotal hallmarks of cancer. This review is giving an updated overview of innovative and upcoming therapies for the treatment of ovarian cancer that focuses specific on the hallmarks of cancer. The hallmarks of cancer constitute a broad concept to reenact complexity of malignancies and furthermore identify possible targets for new treatment strategies. For this purpose, we analyzed approvals and current clinical phase III studies (registered at ClinicalTrials.gov (National Library of Medicine, National Institutes of Health; U.S. Department of Health and Human Services, 2024)) for new drugs on the basis of their mechanisms of action and identified new target approaches. A broad spectrum of new promising drugs is currently under investigation in clinical phase III studies targeting mainly the hallmarks "self-sufficiency in growth signals," "genomic instability," and "angiogenesis." The benefit of immune checkpoint inhibitors in ovarian cancer has been demonstrated for the first time. Besides, targeting the tumor microenvironment is of growing interest. Replicative immortality, energy metabolism, tumor promoting inflammation, and the microbiome of ovarian cancer are still barely targeted by drugs. Nevertheless, precision medicine, which focuses on specific disease characteristics, is becoming increasingly important in cancer treatment.

The association of the chemotherapy response score and homologous recombination deficiency in patients undergoing interval tumor reductive surgery following neoadjuvant chemotherapy

OBJECTIVES

In patients undergoing interval tumor reductive surgery, a good response to neoadjuvant chemotherapy may limit available tumor for homologous recombination deficiency testing. The objective of this study was to assess whether the chemotherapy response score predicts homologous recombination status.

METHODS

We identified patients with advanced epithelial ovarian cancer (diagnosed January 2019 to 20 June 2023) who received neoadjuvant chemotherapy, underwent interval surgery, and for whom a chemotherapy response score was reported (1=no or minimal tumor response, 2=appreciable tumor response, 3=complete or near complete response with no residual tumor). Comparisons were made using ANOVAs or Kruskal-Wallis test for continuous variables and χ2 or Fisher's exact test for categorical variables.

RESULTS

The cohort consisted of 234 patients with advanced ovarian cancer who underwent interval surgery following neoadjuvant chemotherapy. Of those who underwent germline genetic testing, 22% (51/232) had a pathogenic BRCA1 or BRCA2 mutation and of those with tumors sent for testing, 65% were found to have homologous recombination deficiency (66/146). With increasing chemotherapy response scores, a higher likelihood of a complete gross resection was observed (50% (chemotherapy response score, CRS 1) vs 77% (CRS 2) vs 88% (CRS 3), p<0.001). On multivariable analysis, CRS 2 (adjusted odds ratio=3.28, 95% CI 1.12 to 9.60, p=0.03) and CRS 3 (5.83, 1.79 to 18.93, p=0.003) were independently associated with homologous recombination deficiency compared with CRS 1.

CONCLUSION

A positive response to chemotherapy at the time of interval tumor reductive surgery defined by the chemotherapy response score was associated with homologous recombination status and the likelihood of achieving a complete gross resection.

Genomic scarring score predicts the response to PARP inhibitors in non-small cell lung cancer

PARP inhibitors (PARPi) have shown efficacy in tumours harbouring mutations in homologous recombination repair (HRR) genes. Somatic HRR mutations have been described in patients with Non-Small Cell Lung Cancer (NSCLC), but PARP inhibitors (PARPi) are not yet a therapeutic option. Here we assessed the homologous recombination status of early-stage NSCLC and explored the therapeutic benefit of PARPi in preclinical models. The Genomic Scarring Score GSS (GSS) and HRR mutation profile of 136 patients were assessed. High GSS (h-GSS) was observed in 39 (28.7%) patients half of which carried pathogenic/likely pathogenic somatic HRR mutations. TP53 mutations were significantly enriched in h-GSS tumours (p < 0.001). Olaparib significantly delayed tumour growth in h-GSS but not l-GSS Patient-derived Xenografts (PDXs), while patients with h-GSS/TP53mut tumours respond favourably to adjuvant platinum-based chemotherapy. Our functional data clearly support the idea that the use of GSS rather than the mutational status of HRR genes could select patients for administration of PARPi.

Pharmacoproteomics reveals energy metabolism pathways as therapeutic targets of ivermectin in ovarian cancer toward 3P medical approaches

Objective

Ovarian cancer is the malignant tumor with the highest mortality rate in the female reproductive system, enormous socio-economic burden, and limited effective drug therapy. There is an urgent need to find novel effective drugs for ovarian cancer therapy. Our previous in vitro studies demonstrate that ivermectin effectively inhibits ovarian cancer cells and affects energy metabolism pathways. This study aims to clarify in vivo mechanisms and therapeutic targets of ivermectin in the treatment of ovarian cancer to establish predictive biomarkers, guide personalized treatments, and improve preventive strategies in the framework of 3P medicine.

Methods

A TOV-21G tumor-bearing mouse model was constructed based on histopathological data and biochemical parameters. TMT-based proteomic analysis was performed on tumor tissues from the different treatment groups. All significantly differentially abundant proteins were characterized by hierarchical clustering, Gene Ontology (GO) enrichment analyses, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. In addition, the data were integrated and analyzed with the proteomic data of clinical ovarian cancer tissues from our previous study and the proteomic data of ivermectin intervention in ovarian cancer cells to identify key regulators of ivermectin.

Results

Ivermectin (10 mg/kg) had a significant anti-ovarian cancer effect in mice, with a tumor inhibitory rate of 61.5%. Molecular changes in tumor tissue of ivermectin-treated mice were established, and protein-protein interaction (PPI) analysis showed that the main differential pathway networks included the TCA cycle, propanoate metabolism, 2-0xocarboxyacid metabolism, and other pathways. Integrating our previous clinical ovarian cancer tissue and cell experimental data, this study found that ivermectin significantly interfered with the energy metabolic pathways of ovarian cancer, including glycolysis, TCA cycle, oxidative phosphorylation, and other related pathways.

Conclusions

This study evaluated the anti-ovarian cancer effect in vitro and in vivo, and its specific regulatory effect on energy metabolism. The expressions of drug target molecules in the energy metabolism pathway of ovarian cancer will be used to guide the diagnosis and prevention of ovarian cancer. The significant efficacy of ivermectin will be applied to the treatment of ovarian cancer and personalized medication. This has guiding significance for the clinical diagnosis, treatment, personalized medication, and prognosis evaluation of ovarian cancer.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00385-1.

Differential Receipt of Genetic Services Among Patients With Gynecologic Cancer and Their Relatives: A Review of Challenges to Health Equity

Up to 14% of endometrial cancers and 23% of epithelial ovarian cancers are associated with genetic predispositions. Referral for genetic testing and counseling can significantly impact a patient's oncologic outcomes. However, significant disparities in genetic referral and testing exist within medically underserved and minority populations in the United States. These disparities in care and access to care are multifactorial, often involving patient-level, health care-level, and system-level factors. In this review, we focus on disparities in genetic testing among patients with ovarian and uterine cancer, and the missed opportunities for primary cancer prevention among their relatives.

PARG inhibitor sensitivity correlates with accumulation of single-stranded DNA gaps in preclinical models of ovarian cancer

Poly (ADP-ribose) glycohydrolase (PARG) is a dePARylating enzyme which promotes DNA repair by removal of poly (ADP-ribose) (PAR) from PARylated proteins. Loss or inhibition of PARG results in replication stress and sensitizes cancer cells to DNA-damaging agents. PARG inhibitors are now undergoing clinical development for patients having tumors with homologous recombination deficiency (HRD), such as cancer patients with germline or somatic BRCA1/2-mutations. PARP inhibitors kill BRCA-deficient cancer cells by increasing single-stranded DNA gaps (ssGAPs) during replication. Here, we report that, like PARP inhibitor (PARPi), PARG inhibitor (PARGi) treatment also causes an accumulation of ssGAPs in sensitive cells. PARGi exposure increased accumulation of S-phase-specific PAR, a marker for Okazaki fragment processing (OFP) defects on lagging strands and induced ssGAPs, in sensitive cells but not in resistant cells. PARGi also caused accumulation of PAR at the replication forks and at the ssDNA sites in sensitive cells. Additionally, PARGi exhibited monotherapy activity in specific HR-deficient, as well as HR-proficient, patient-derived, or patient-derived xenograft (PDX)-derived organoids of ovarian cancer, and drug sensitivity directly correlated with the accumulation of ssGAPs. Taken together, PARGi treatment results in toxic accumulation of PAR at replication forks resulting in ssGAPs due to OFP defects during replication. Regardless of the BRCA/HRD-status, the induction of ssGAPs in preclinical models of ovarian cancer cells correlates with PARGi sensitivity. Patient-derived organoids (PDOs) may be a useful model system for testing PARGi sensitivity and functional biomarkers.

Efficacy and safety of angiogenesis inhibitors combined with poly ADP ribose polymerase inhibitors in the maintenance treatment of advanced ovarian cancer: a meta-analysis

INTRODUCTION

This meta-analysis was performed to evaluate the efficacy and safety of angiogenesis inhibitors (Ais) combined with poly ADP ribose polymerase inhibitors (PARPi) in the maintenance treatment of advanced ovarian cancer (OC).

MATERIALS AND METHODS

A systematic search was conducted in four databases (Pubmed, Embase, Web of Science, and Cochrane) for articles published from the inception of the databases until January 15, 2024. The focus of the search was on articles investigating the combination of Ais with PARPi in the maintenance treatment of ovarian cancer. Meta-analyses were conducted to assess the objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and the risk of Grade ≥ 3 adverse events (Grade≥ 3 AEs).

RESULTS

Totally nine studies were included for meta-analysis. The overall pooled ORR of Ais combined with PARPi was 57% (95% CI, 35% to 77%). Subgroup analyses showed that the ORR for patients with platinum-resistant recurrent ovarian cancer, platinum-sensitive recurrent ovarian cancer and newly diagnosed advanced ovarian cancer were 30% (95% CI, 12% to 52%), 70% (95% CI, 61% to 78%) and 59% (95% CI, 55% to 63%), respectively. The median PFS was 5.8 months (95% CI, 5.3 to 7.1), 12.4 months (95% CI, 10.6 to 13.2) and 22.4 months (95% CI, 21.5 to 24.2), respectively. The median OS was 15.5 months (95% CI, 12.3 to 24.8), 40.8 months (95% CI, 33.4 to 45.2) and 56.3 months (95% CI, 49.0 to 62.0), respectively. The rate Grade≥ 3 TRAEs rate was found to be 0.22 (95% CI, 0.13 to 0.33).

CONCLUSIONS

Our results confirmed that PARPi plus Ais was a feasible and safe option for the maintenance treatment of advanced ovarian cancer. The combination therapy should be recommended as the first-line maintenance treatment for patients with advanced ovarian cancer. PARPi plus Ais yielded more favorable oncological prognosis for patients with platinum-sensitive recurrent ovarian cancer, compared to patients with platinum-resistant recurrent ovarian cancer.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024543590, identifier CRD42024543590.

Long-read sequencing of an advanced cancer cohort resolves rearrangements, unravels haplotypes, and reveals methylation landscapes

The Long-Read Personalized OncoGenomics (POG) dataset comprises a cohort of 189 patient tumors and 41 matched normal samples sequenced using the Oxford Nanopore Technologies PromethION platform. This dataset from the POG program and the Marathon of Hope Cancer Centres Network includes DNA and RNA short-read sequence data, analytics, and clinical information. We show the potential of long-read sequencing for resolving complex cancer-related structural variants, viral integrations, and extrachromosomal circular DNA. Long-range phasing facilitates the discovery of allelically differentially methylated regions (aDMRs) and allele-specific expression, including recurrent aDMRs in the cancer genes RET and CDKN2A. Germline promoter methylation in MLH1 can be directly observed in Lynch syndrome. Promoter methylation in BRCA1 and RAD51C is a likely driver behind homologous recombination deficiency where no coding driver mutation was found. This dataset demonstrates applications for long-read sequencing in precision medicine and is available as a resource for developing analytical approaches using this technology.

Case report: High grade serous fallopian tube carcinoma with rare NRG1 gene fusion presenting as widespread peritoneal carcinomatosis

The discovery of gene fusions involving Neuregulin-1 (NRG1) within solid tumors has important therapeutic implications, as they are being actively explored as targets for emerging ERBB/ERBB2/ERBB3-directed anti-cancer agents. NRG1 fusions are very uncommon across all tumor types and are infrequently documented in the medical literature. We report a female patient presenting with widespread peritoneal carcinomatosis diagnosed as high grade serous fallopian tube carcinoma, which harbored a previously undescribed MYH10::NRG1 fusion. Moreover, we queried the whole transcriptome sequencing results of neoplasms analyzed by a commercial laboratory (Caris Life Sciences) to determine the overall incidence of NRG1 fusions in carcinomas of the ovary, fallopian tube, and peritoneum (0.18%). Twenty-five additional tumors were found to demonstrate NRG1 fusions, including 20 new genes partners that had not been previously identified in gynecologic carcinomas. Overall, NRG1 fusion events are rare in ovarian, fallopian tube, and primary peritoneal carcinomas, but they may carry diagnostic significance in the context of borderline/low grade serous tumors, which demonstrated exclusively CLU::NRG1 fusions, and could have important predictive implications for response to ERBB/ERBB2/ERBB3-directed therapies.

PARP inhibitors in ovarian cancer: Mechanisms, resistance, and the promise of combination therapy

Current approaches to treating ovarian cancer focus mainly on surgical cytoreduction and chemotherapy using platinum-based drugs, while newer methods such as immunotherapy are being investigated to enhance treatment outcomes. Treating ovarian cancer is complicated by challenges such as late-stage detection, tumor diversity, and limited treatment choices. Therefore, innovative strategies such as precision medicine and targeted therapies like PARPi (Poly ADP-Ribose Polymerase inhibitors) are increasingly necessary. The article highlights the significance of an innovative therapeutic approach focusing on PARPi in revolutionizing ovarian cancer treatment and improving patient outcomes. It covers the basic knowledge of PARP, its structure, and its function in DNA repair. It further emphasizes how inhibiting PARP can help in treating ovarian cancer. It elaborates on the mechanism of action of PARPi. It covers the clinical trials governing PARPi and the combination of drugs used with PARPi. It mentions how the resistance is developed to PARPi and the strategies to overcome the resistance developed.

Role of Fyn expression in predicting the sensitivity to platinum‑based chemotherapy in patients with ovarian serous carcinoma

Ovarian serous carcinoma is a gynecological malignancy associated with a high mortality rate, which is commonly diagnosed in the first instance at a late stage and has a propensity to develop resistance to platinum-based chemotherapy. Identifying reliable biomarkers for platinum sensitivity is critical for improving patient outcomes. The present retrospective study included 64 patients with high-grade serous ovarian carcinoma (Federation of Gynecology and Obstetrics stages III or IV). Patients were classified as platinum-sensitive (no relapse within 6 months of the last platinum administration) or platinum-resistant (relapse within 6 months). Immunohistochemical analysis was performed to evaluate Fyn expression in tumor tissues, and Fyn knockdown experiments were performed using the OVSAHO ovarian cancer cell line to assess carboplatin sensitivity. Fyn expression was significantly higher in platinum-resistant patients compared with in platinum-sensitive patients (P<0.01). A weighted Fyn expression score was developed and a cutoff score of 6 was determined to predict platinum sensitivity with a specificity of 65.5% and a sensitivity of 62.9%. Patients with low Fyn expression (score ≤6) exhibited higher platinum sensitivity and longer overall survival (P<0.05). Multivariate analysis identified Fyn expression and postoperative residual tumor size as independent predictors of platinum sensitivity (P=0.033 and P=0.023, respectively). In vitro, Fyn knockdown significantly increased carboplatin sensitivity in ovarian cancer cells (P<0.05). Fyn, a member of the Src family of kinases, serves a crucial role in various cellular functions and has been implicated in chemotherapy resistance. The results demonstrated a notable association between Fyn expression and platinum sensitivity in ovarian serous carcinoma. The findings suggested that Fyn may serve as a predictive biomarker for response to platinum-based chemotherapy, offering the potential for more personalized treatment strategies. To the best of our knowledge, the present study is the first to establish an association between Fyn expression and platinum sensitivity in advanced ovarian serous carcinoma. Prospective studies with larger, multi-center cohorts and comprehensive biomarker analyses are recommended to validate and extend these results, ultimately improving therapeutic strategies and patient prognosis.

PARP inhibitor-related acute renal failure: a real-world study based on the FDA adverse event reporting system database

BACKGROUND

Current clinical trial data on PARP inhibitors (PARPis)-related acute renal failure (ARF) are not entirely representative of real-world situations. Therefore, in this study, the US Food and Drug Administration Adverse Event Reporting System (FAERS) was used to evaluate PARPis-related ARF.

RESEARCH DESIGN AND METHODS

Data were obtained from 1 January 2015, to 30 September 2023. ARF event reports were analyzed based on four algorithms. The time-to-onset (TTO) and clinical outcomes of PARPis-associated ARF were assessed.

RESULTS

The total included cases were 2726. Significant signals were observed for olaparib, niraparib, and rucaparib (reporting odds ratio (ROR): 1.62, 95% confidence interval (CI): 1.49-1.78, 1.25, 95% CI: 1.19-1.32 and 1.59, 95% CI: 1.47-1.72 respectively). The median TTO of ARF onset was 57, 36, and 85 days for olaparib, niraparib, and rucaparib, respectively. The proportion of deaths with olaparib (9.88%) was significantly higher than for niraparib (2.52%) and rucaparib (2.94%) (p < 0.005). The proportion of life-threatening adverse events associated with niraparib (4.89%) was significantly higher than for rucaparib (0.98%) (p < 0.005).

CONCLUSIONS

ARF and PARPi were related, with the exception of talazoparib. More emphasis should be given to PARPis-related ARF due to the high proportion of serious AEs and delayed adverse reactions.

Impact of PARP inhibitors on progression-free survival in platinum-sensitive recurrent epithelial ovarian cancer: a retrospective analysis

OBJECTIVE

Poly (ADP-ribose) polymerase (PARP) inhibitors such as olaparib and niraparib have shown promise in extending progression-free survival (PFS) in patients with platinum-sensitive recurrent (PSR) epithelial ovarian cancer. In this retrospective study, we aimed to present our own data on the effect of PARP inhibitors on PFS in recurrent epithelial ovarian cancer.

METHODS

82 patients diagnosed with PSR epithelial ovarian, tubal, or primary peritoneal cancer between May 2017 and September 2023 were initially enrolled from our hospital. However, 16 patients had prior exposure to PARP inhibitors during primary treatment, and 11 were lost to follow-up. Consequently, the study focused on 55 eligible patients. PFS was compared between patients receiving PARP inhibitor maintenance therapy and those who did not.

RESULTS

Among the 55 patients with PSR epithelial ovarian cancer, 18 received olaparib as maintenance therapy, 19 received niraparib, and 18 opted for observation. PARP inhibitor therapy significantly extended PFS (mean 24.0 months) compared to observation (mean 9.0 months, p = 0.0005), regardless of BRCA mutation status (HR = 0.20, 95% CI: 0.08-0.50). Subgroup analysis showed no statistical difference between olaparib and niraparib. Additionally, there was no PFS difference based on BRCA mutation status within both PARP inhibitor groups.

CONCLUSION

Our retrospective study demonstrates that PARP inhibitor maintenance therapy, including olaparib and niraparib, significantly prolongs PFS in patients with PSR epithelial ovarian, tubal, or primary peritoneal cancer, These findings support the broad utilization of PARP inhibitors as a standard maintenance therapy for PSR epithelial ovarian cancer irrespective of BRCA mutation status.

Cabozantinib inhibits tumor growth in mice with ovarian cancer

Ovarian cancer is usually detected in the advanced stages. Existing treatments for high grade serous ovarian cancer (HGSOC) are not adequate and approximately fifty percent of patients succumb to this disease and die within five years after diagnosis. We conducted pre-clinical studies in a mouse model of ovarian cancer to evaluate disease outcome in response to treatment with the multi-kinase inhibitor cabozantinib. Cabozantinib is a receptor tyrosine kinase inhibitor with multiple targets including vascular endothelial growth factor receptor-2 (VEGFR-2), associated with immune suppression in ovarian cancer. Mice (C57BL/6) were injected with ID8-RFP ovarian tumor cells and treated with cabozantinib. Studies investigated ascites development, tumor burden and regulation of anti-tumor immunity with treatment. Mice treated with cabozantinib had significantly decreased solid tumor burden and decreased malignant ascites as compared to untreated controls. Improved outcome in cabozantinib treated mice was associated with a significantly higher percentage of CD69 early activated T cells, a higher percentage of granzyme B secreting CD8 T cells, the enhanced release of cytokines and chemokines known to recruit CD8 T cells and amplify T cell function, as well as reduced VEGFR-2. Findings suggest that cabozantinib is an important clinical agent capable of improving ovarian cancer in mice potentially in part by priming the autologous immune system to promote anti-tumor immunity.

Synthesis of 5-hydroxyisatin thiosemicarbazones, spectroscopic investigation, protein-ligand docking, and in vitro anticancer activity

A series of novel modifications were performed at the N(4) position of 5-hydroxyisatin thiosemicarbazone (TSC). The structure-activity approach is applied to design and synthesize derivatives by condensing thiosemicarbazides with 5-hydroxy isatin. The TSCs were characterized by various spectroscopic techniques viz. FTIR, 1H NMR, 13C NMR, UV-Vis, HRMS data, CHN elemental analysis, and single crystal X-ray diffraction. Biological evaluation of the synthesized compounds revealed the anticancer potency of the TSC analogues against breast cancer (MD-AMD-231, MCF-7), lung cancer (A549, NCI-H460), prostate cancer (PC3), and skin cancer (A431). The molecules, L2, L3, and L6 showed activity in the micromolar range (IC50; 0.19-2.19 μM). L6 exhibited the highest potency against skin cancer A431 cell line, with an IC50 of 0.19 μM compared to 1.8 μM with triapine and showed low toxicity against PNT-2 cells with an SI index of >100 μM. The mechanistic study revealed that L6 inhibited cancer cell proliferation, colony formation, and 3-dimensional spheroid formation by targeting the Ras/MAPK axis. It induced DNA damage and impaired DNA damage repair machinery, which led to the accumulation of DSB. Also, it lowered the ERK1/2 expression, which affected the caspase 3 activity and showed higher binding affinity compared to the FDA-approved drug Lenalidomide in molecular docking studies. Our findings demonstrated the possible future anticancer drug potency of L6 in the skin cancer A431 cells.

Poly(ADP-Ribose) Polymerase (PARP) Inhibitors for Cancer Therapy: Advances, Challenges, and Future Directions

Poly(ADP-ribose) polymerases (PARPs) are crucial nuclear proteins that play important roles in various cellular processes, including DNA repair, gene transcription, and cell death. Among the 17 identified PARP family members, PARP1 is the most abundant enzyme, with approximately 1-2 million molecules per cell, acting primarily as a DNA damage sensor. It has become a promising biological target for anticancer drug studies. Enhanced PARP expression is present in several types of tumors, such as melanomas, lung cancers, and breast tumors, correlating with low survival outcomes and resistance to treatment. PARP inhibitors, especially newly developed third-generation inhibitors currently undergoing Phase II clinical trials, have shown efficacy as anticancer agents both as single drugs and as sensitizers for chemo- and radiotherapy. This review explores the properties, characteristics, and challenges of PARP inhibitors, discussing their development from first-generation to third-generation compounds, more sustainable synthesis methods for discovery of new anti-cancer agents, their mechanisms of therapeutic action, and their potential for targeting additional biological targets beyond the catalytic active site of PARP proteins. Perspectives on green chemistry methods in the synthesis of new anticancer agents are also discussed.

Design, synthesis and antitumor activities of phthalazinone derivatives as PARP-1 inhibitors and PARP-1/HDAC-1 inhibitors

In recent years, poly(ADP-ribose)polymerase-1 (PARP-1) and histone deacetylase (HDAC) have emerged as significant targets in tumor therapy, garnering widespread attention. In this study, we designed and synthesized two novel phthalazinone PARP-1 inhibitors and dual PARP-1/HDAC-1 inhibitors, named DLC-1-46 containing dithiocarboxylate fragments and DLC-47-63 containing hydroxamic acid fragments, and evaluated their inhibitory activities on enzymes and cells. Among the PARP-1 inhibitors, most compounds exhibited high inhibitory activity against the PARP-1 enzyme, with DLC-1-6 being particularly notable, showing IC50 values <0.2 nM. Notably, DLC-1 demonstrated significant anti-proliferative activity, with IC50 values for inhibiting the proliferation of MDA-MB-436, MDA-MB-231, and MCF-7 cells reaching 0.08, 26.39, and 1.01 μM, respectively. Further investigation revealed that DLC-1 arrested MDA-MB-231 cells in the G1 phase and induced apoptosis in a dose-dependent manner. Among the designed dual PARP-1/HDAC-1 inhibitors, several compounds exhibited potent dual-target inhibitory activity, with DLC-49 displaying IC50 values of 0.53 nM and 17 nM for PARP-1 and HDAC-1, respectively. DLC-50 demonstrated the most potent anti-proliferative activity, with IC50 values for inhibiting the proliferation of MDA-MB-436, MDA-MB-231, and MCF-7 cells at 0.30, 2.70, and 2.41 μM, respectively. Cell cycle arrest and apoptosis assays indicated that DLC-50 arrested the cell cycle in the G2 phase and induced apoptosis in HCT-116 cells. Our findings present a novel avenue for further exploration of PARP-1 inhibitors and dual PARP-1/HDAC-1 inhibitors.

A comprehensive review on the potential of coumarin and related derivatives as multi-target therapeutic agents in the management of gynecological cancers

Current treatments for gynecological cancers include surgery, radiotherapy, and chemotherapy. However, these treatments often have significant side effects. Phytochemicals, natural compounds derived from plants, offer promising anticancer properties. Coumarins, a class of benzopyrone compounds found in various plants like tonka beans, exhibit notable antitumor effects. These compounds induce cell apoptosis, target PI3K/Akt/mTOR signaling pathways, inhibit carbonic anhydrase, and disrupt microtubules. Additionally, they inhibit tumor multidrug resistance and angiogenesis and regulate reactive oxygen species. Specific coumarin derivatives, such as auraptene, praeruptorin, osthole, and scopoletin, show anti-invasive, anti-migratory, and antiproliferative activities by arresting the cell cycle and inducing apoptosis. They also inhibit metalloproteinases-2 and -9, reducing tumor cell migration, invasion, and metastasis. These compounds can sensitize tumor cells to radiotherapy and chemotherapy. Synthetic coumarin derivatives also demonstrate potent antitumor and anticancer activities with minimal side effects. Given their diverse mechanisms of action and minimal side effects, coumarin-class phytochemicals hold significant potential as therapeutic agents in gynecological cancers, potentially improving treatment outcomes and reducing side effects. This review will aid in the synthesis and development of novel coumarin-based drugs for these cancers.

Genetic landscape of homologous recombination repair and practical outcomes of PARPi therapy in ovarian cancer management

Background

Genetic studies of ovarian cancer (OC) have historically focused on BRCA1/2 mutations, lacking other studies of homologous recombination repair (HRR). Poly (ADP-ribose) polymerase inhibitors (PARPi) exploit synthetic lethality to significantly improve OC treatment outcomes, especially in BRCA1/2 deficiency patients.

Objectives

Our study aims to construct a mutation map of HRR genes in OC and identify factors influencing the efficacy of PARPi.

Design

A retrospective observational analysis of HRR gene variation data from 695 OC patients from March 2019 to February 2022 was performed.

Methods

The HRR gene variation data of 695 OC patients who underwent next-generation sequencing (NGS) in the First Affiliated Hospital of Zhengzhou University were retrospectively collected. Clinical data on the use of PARPi in these patients were also gathered to identify factors that may interfere with the efficacy of PARPi.

Results

Out of 127 pathogenic variants in the BRCA1/2 genes, 104 (81.9%) were BRCA1 mutations, and 23 (18.1%) were BRCA2 mutations. Among the 59 variants of uncertain significance (VUS), 20 (33.9%) were BRCA1, while 39 (66.1%) were BRCA2 mutations. In addition to BRCA1/2, HRR gene results showed that 9 (69%) of 13 were HRR pathway pathogenic variants; and 16 (1.7%) of 116 VUS were Food and Drug Administration (FDA)-approved mutated HRR genes. Notably, the treatment regimen significantly influenced the effectiveness of PARPi, especially when using first-line maintenance therapy, leading to enhanced progression-free survival (PFS) compared to alternative protocols.

Conclusion

Focusing on HRR gene mutations and supporting clinical research about PARPi in OC patients is crucial for developing precision treatment strategies and enhancing prognosis.

Association of PARP1 Expression Levels and Clinical Parameters in Different Leukemic Subtypes With BCR::ABL1 p190+ Translocation

Background/Aim

Although the reciprocal translocation t(9;22)(q34;q11) is a hallmark of chronic myeloid leukemia (CML), it is also present in acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). Depending on the gene's breakpoint, it is possible to obtain three isoforms, among which p190 stands out for the poor prognosis it induces whenever it appears. Due to the genomic instability induced by BCR::ABL1, it is proposed to expand the applicability of poly-ADP-ribose polymerase-1 (PARP1) and its inhibitors in hematological neoplasms.

Materials and Methods

We measured the expression levels of PARP1 by quantitative real-time PCR (qPCR) using TaqMan®, correlating its expression with BCR::ABL1 p190+, to evaluate its influence in the clinic of adult patients.

Results

We found that PARP1 is expressed differently in ALL, AML and CML and that p190 transcripts do not follow a linear pattern in these populations. We also found that PARP1 expression is not correlated with age, white blood cell and the amount of p190 transcripts.

Conclusion

Despite the lack of statistical correlation between the variables analyzed, the role of PARP1 in BCR::ABL1 leukemia cannot be ruled out, given the instability profile promoted by this translocation. Finally, further studies involving a larger sample of patients are needed, as well as investigations into other molecular pathways that may impact on the pathogenesis of different BCR::ABL1 leukemic subtypes.

Guidelines of the Brazilian Society of Surgical Oncology for anatomopathological, immunohistochemical, and molecular testing in female tumors

INTRODUCTION

Precision medicine has revolutionized oncology, providing more personalized diagnosis, treatment, and monitoring for patients with cancer. In the context of female-specific tumors, such as breast, ovarian, endometrial, and cervical cancer, proper tissue collection and handling are essential for obtaining tissue, immunohistochemical (IHC), and molecular data to guide therapeutic decisions.

OBJECTIVES

To establish guidelines for the collection and handling of tumor tissue, to enhance the quality of samples for histopathological, IHC, genomic, and molecular analyses. These guidelines are fundamental in informing therapeutic decisions in cancer treatment.

METHOD

The guidelines were developed by a multidisciplinary panel of renowned specialists between June 12, 2013 and February 12, 2024. Initially, the panel deliberated on critical and controversial topics related to conducting precision medicine studies focusing on female tumors. Subsequently, 22 pivotal topics were identified within the framework and assigned to groups. These groups reviewed relevant literature and drafted preliminary recommendations. Following this, the recommendations were reviewed by the coordinators and received unanimous approval. Finally, the groups made the final adjustments, classified the level of evidence, and ranked the recommendations.

CONCLUSION

The collection of surgical samples requires minimum quality standards to enable histopathological, IHC, genomic, and molecular analyses. These analyses provide crucial data for informing therapeutic decisions, significantly impacting potential survival gains for patients with female tumors.

Overview of BH3 mimetics in ovarian cancer

Ovarian carcinoma is the leading cause of gynecological cancer-related death, still with a dismal five-year prognosis, mainly due to late diagnosis and the emergence of resistance to cytotoxic and targeted agents. Bcl-2 family proteins have a key role in apoptosis and are associated with tumor development/progression and response to therapy in different cancer types, including ovarian carcinoma. In tumors, evasion of apoptosis is a possible mechanism of resistance to therapy. BH3 mimetics are small molecules that occupy the hydrophobic pocket on pro-survival proteins, allowing the induction of apoptosis, and are currently under study as single agents and/or in combination with cytotoxic and targeted agents in solid tumors. Here, we discuss recent advances in targeting anti-apoptotic proteins of the Bcl-2 family for the treatment of ovarian cancer, focusing on BH3 mimetics, and how these approaches could potentially offer an alternative/complementary way to treat patients and overcome or delay resistance to current treatments.

Leveraging PARP-1/2 to Target Distant Metastasis

Poly (ADP-Ribose) Polymerase (PARP) inhibitors have changed the outcomes and therapeutic strategy for several cancer types. As a targeted therapeutic mainly for patients with BRCA1/2 mutations, PARP inhibitors have commonly been exploited for their capacity to prevent DNA repair. In this review, we discuss the multifaceted roles of PARP-1 and PARP-2 beyond DNA repair, including the impact of PARP-1 on chemokine signalling, immune modulation, and transcriptional regulation of gene expression, particularly in the contexts of angiogenesis and epithelial-to-mesenchymal transition (EMT). We evaluate the pre-clinical role of PARP inhibitors, either as single-agent or combination therapies, to block the metastatic process. Efficacy of PARP inhibitors was demonstrated via DNA repair-dependent and independent mechanisms, including DNA damage, cell migration, invasion, initial colonization at the metastatic site, osteoclastogenesis, and micrometastasis formation. Finally, we summarize the recent clinical advancements of PARP inhibitors in the prevention and progression of distant metastases, with a particular focus on specific metastatic sites and PARP-1 selective inhibitors. Overall, PARP inhibitors have demonstrated great potential in inhibiting the metastatic process, pointing the way for greater use in early cancer settings.

FLT1 activation in cancer cells promotes PARP-inhibitor resistance in breast cancer

Acquired resistance to PARP inhibitors (PARPi) remains a treatment challenge for BRCA1/2-mutant breast cancer that drastically shortens patient survival. Although several resistance mechanisms have been identified, none have been successfully targeted in the clinic. Using new PARPi-resistance models of Brca1- and Bard1-mutant breast cancer generated in-vivo, we identified FLT1 (VEGFR1) as a driver of resistance. Unlike the known role of VEGF signaling in angiogenesis, we demonstrate a novel, non-canonical role for FLT1 signaling that protects cancer cells from PARPi in-vivo through a combination of cell-intrinsic and cell-extrinsic pathways. We demonstrate that FLT1 blockade suppresses AKT activation, increases tumor infiltration of CD8+ T cells, and causes dramatic regression of PARPi-resistant breast tumors in a T-cell-dependent manner. Moreover, PARPi-resistant tumor cells can be readily re-sensitized to PARPi by targeting Flt1 either genetically (Flt1-suppression) or pharmacologically (axitinib). Importantly, a retrospective series of breast cancer patients treated with PARPi demonstrated shorter progression-free survival in cases with FLT1 activation at pre-treatment. Our study therefore identifies FLT1 as a potential therapeutic target in PARPi-resistant, BRCA1/2-mutant breast cancer.

Prescribers and patients drive maintenance therapy patterns in a community oncology practice: National guidelines versus the real-world experience

Objective

Previous studies have shown that first-line (1L) maintenance therapy (MT) with poly(ADP-ribose) polymerase inhibitors and/or bevacizumab improves outcomes among patients with advanced ovarian cancer (OC); however, these treatments are underutilized. This study aimed to provide a real-world understanding of MTs among patients with advanced OC who received 1L platinum-based chemotherapy (PBC).

Methods

A retrospective chart review using iKnowMed electronic health records to identify patients aged ≥18 years with advanced OC who initiated 1L PBC between January 1, 2018-December 31, 2020. Following 1L PBC, patients could have received MT or active surveillance (AS). Kaplan-Meier methods were used to estimate time to treatment discontinuation (TTD), real-world progression-free survival (rwPFS), and overall survival (OS).

Results

Of the 600 chart-reviewed patients included, 239 (39.8 %) received MT and 315 (52.5 %) received AS. Patients who were <65 years of age, or those with higher-stage disease or those who had received neoadjuvant treatment, were more likely to initiate MT than AS. Genetic testing rates were low across both cohorts. Median (95 % confidence interval [CI]) TTD for the MT cohort was 13.6 months (11.0, 21.2). Median (95 % CI) rwPFS was 26.9 months (21.3, not reached) and 11.3 months (9.5, 13.0) for the 1L MT and AS cohorts, respectively (p < 0.0001). OS at 36 months was 82.4 % in the 1L MT cohort and 58.0 % in the 1L AS cohort.

Conclusions

This study reinforces clinical trial findings that 1L MT improves outcomes in patients with advanced OC; however, genetic testing rates and 1L MT remained low.

Trends in estimated PARP inhibitor eligibility and benefit among US epithelial ovarian cancer patients

OBJECTIVE

To estimate the annual percentage of patients with epithelial ovarian cancer (EOC) who could be eligible for and benefit from PARP inhibitor therapy amidst changing US Food and Drug Administration (FDA)-approved indications.

METHODS

This is a simulated retrospective observational study using publicly available data on patients with advanced-stage EOC. PARPi eligibility is based on FDA approvals and withdrawals from 2014 through 2023, along with published demographic and genomic data. Clinical trial data is used to estimate treatment benefit. PARPi including olaparib, niraparib, and rucaparib are analyzed in aggregate with sub-analyses by molecular classification and treatment timing. Results are reported as the percentage of EOC patients appropriate for any cancer-directed therapy.

RESULTS

PARPi were approved for 9 different indications in EOC between 2014 and 2021; reduced to 6 indications by 2023. Eligibility increased from 2.0% (95% CI,1.3%-1.6%) in 2014 to a maximum of 93.4% (95% CI,90.1%-94.6%) in 2021. The maximum percentage of patients with 2-year PFS benefit was 22.0% (95% CI, 17.2%-26.8%) in 2021, projected to decrease to 13.0% (95% CI, 9.9%-15.9%) in 2024. Most of this decrease was seen in the homologous recombination deficient, BRCA wild-type population (8.4% to 4.0%).

CONCLUSIONS

PARPi eligibility increased at a greater rate than benefit resulting in a low population-level benefit-to-eligibility ratio until 2021. Recent FDA withdrawals improved this ratio with an accompanied decrease in the absolute number of patients benefiting. To further optimize population-level benefit-to-eligibility ratio of targeted therapies in ovarian cancer, we need to identify better biomarkers, treatment combinations, and novel therapeutic targets.