Rationale for combination PARP inhibitor and antiangiogenic treatment in advanced epithelial ovarian cancer: A review

Does Aspirin Use Reduce the Risk for Ovarian Cancer?

Ovarian cancer is an aggressive malignancy and the leading cause of death among gynecologic cancers. Researchers have evaluated prophylactic medications that potentially avert the manifestation of ovarian cancer, but currently, there are no reliable screening measures for this disease. Nevertheless, the largest study involving aspirin use and ovarian cancer reported a substantive risk reduction from enduring aspirin use. Since there are countervailing data to impugn the potential benefits of aspirin use in staving off ovarian cancer, further research should scrutinize the use of this medication as a prophylactic intervention, especially in women who are at higher risk for developing the disease.

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.

The first real-world study on the role of carbon ion radiotherapy for oligo-metastatic, persistent, or recurrent (MPR) ovarian/fallopian tube cancer

Introduction

In the multidisciplinary management of oligometastatic, persistent, or recurrent (MPR) ovarian cancer, radiotherapy (RT) is becoming a more and more worthwhile treatment to potentially improve the chronicity of the disease. Particle beam RT has proved to be effective in several gynecological malignancies, but so far no data are available for ovarian cancer.

Material and Methods

This is a real-world, retrospective, bi-institutional, single-arm study aimed to assess the effectiveness and the safety of carbon ion RT (CIRT) in this setting. The co-first endpoints are 1-year and 2-year actuarial local control (LC) rates and the objective response rate (ORR) defined on a "per lesion" basis. The secondary endpoint was toxicity. Actuarial outcomes were evaluated using the Kaplan-Meier method while potential predictors were explored using the Log-rank test. Bi-variable logistic regression was employed in the analysis of factors predicting the complete response on a per-lesion basis.

Results

26 patients accounting for a total of 36 lesions underwent CIRT with a total median dose of 52.8 Gy[RBE] (range: 39-64 Gy[RBE]). Five patients received CIRT for re-irradiation. No concomitant systemic therapies were administered during CIRT. Within 12 months after the treatment, 17 lesions (47 %) achieved complete response while 18 (50 %) obtained a partial response with an ORR of 97 %. The achievement of a complete response is related to the dose per fraction (>4.2 Gy[RBE], p = 0.04) and total dose (>52,8 Gy[RBE], p = 0.05). The 1-year LC was 92 % and the 2-year LC was 83 %, according to the achievement of a CR (p = 0.007) and GTV ≤ 14 cm3 (p = 0.024). No grade > 3 toxicities were recorded both in naïve and re-irradiated patients. PARP-i and anti-VEGF seemed not to exacerbate the risk of severe toxicities.

Conclusions

CIRT was effective and safe in MPR ovarian cancers, even in the case of re-irradiation. Largest cohort studies and longer follow-up are needed to confirm these data.

Prospects and challenges of CAR-T in the treatment of ovarian cancer

Ovarian cancer ranks as the seventh most prevalent cancer among women and is considered the most lethal gynecological malignancy on a global scale. The absence of reliable screening techniques, coupled with the insidious onset of nonspecific symptoms, often results in a delayed diagnosis, typically at an advanced stage characterized by peritoneal involvement. Management of advanced tumors typically involves a combination of chemotherapy and cytoreductive surgery. However, the therapeutic arsenal for ovarian cancer patients remains limited, highlighting the unmet need for precise, targeted, and sustained-release pharmacological agents. Genetically engineered T cells expressing chimeric antigen receptors (CARs) represent a promising novel therapeutic modality that selectively targets specific antigens, demonstrating robust and enduring antitumor responses in numerous patients. CAR T cell therapy has exhibited notable efficacy in hematological malignancies and is currently under investigation for its potential in treating various solid tumors, including ovarian cancer. Currently, numerous researchers are engaged in the development of novel CAR-T cells designed to target ovarian cancer, with subsequent evaluation of these candidate cells in preclinical studies. Given the ability of chimeric antigen receptor (CAR) expressing T cells to elicit potent and long-lasting anti-tumor effects, this therapeutic approach holds significant promise for the treatment of ovarian cancer. This review article examines the utilization of CAR-T cells in the context of ovarian cancer therapy.

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.

Current Analytical Methods for the Sensitive Assay of New-Generation Ovarian Cancer Drugs in Pharmaceutical and Biological Samples

Ovarian cancer, which affects the female reproductive organs, is one of the most common types of cancer. Since this type of cancer has a high mortality rate from gynaecological cancers, the scientific community shows great interest in studies on its treatment. Chemotherapy, radiotherapy, and surgical treatment methods are used in its treatment. In the absence of targeted treatments in these treatment methods, side effects occur in patients, and patients show resistance to the drug. In addition, the underlying causes of ovarian cancer are still not fully known. The scientific world thinks that genetic factors, environmental conditions, and consumed foods may cause this cancer. The most important factor in the treatment of ovarian cancer is early diagnosis. Therefore, the drugs used in the treatment of ovarian cancer are platinum-based anticancer drugs. In addition to these drugs, the most preferred treatment method recently is targeted treatment approaches using poly(adenosine diphosphate ribose) polymerase (PARP) inhibitors. In this review, studies on the sensitive analysis of the treatment methods of these new-generation drugs used in the treatment of ovarian cancer have been comprehensively examined. In addition, the basic features, structural aspects, and biological data of analytical methods used in treatments with new-generation drugs are explained. Analytical studies carried out in the literature in recent years aim to show future developments in how these new-generation drugs are used today and to guide future studies by comprehensively examining and explaining the structure-activity relationship, mechanism of action, toxicity, and pharmacokinetic studies. Finally, in this study, the methods used in the analysis of drugs used in the treatment of ovarian cancer and the studies conducted between 2015 and 2023 were discussed in detail.

Efficacy and safety of PARP inhibitors combined with antiangiogenic agents in the maintenance treatment of ovarian cancer: a systematic review and meta-analysis with trial sequential analysis of randomized controlled trials

Background: Poly (ADP-ribose) polymerase (PARP) inhibitor and antiangiogenic agent monotherapy have shown to be effective as maintenance treatment in patients with ovarian cancer (OC). However, there is currently a lack of evidence-based study to directly compare the effects of combination therapy with these two drugs. Therefore, this study aimed to compare the efficacy and safety of combination therapy with PARP inhibitors and antiangiogenic agents in women with OC using a meta-analysis. Methods: An exhaustive search of literature was undertaken using multiple databases, including PubMed, Web of Science, Embase, and the Cochrane Library to identify pertinent randomized controlled trials (RCTs) published up until 17 December 2023. The data on progression-free survival (PFS), overall survival (OS), and adverse events (AEs) were pooled. We computed the pooled hazard ratios (HRs) and their 95% confidence intervals (CIs) for PFS and OS, along with the relative risks (RRs) and 95% CIs for AEs. Trial sequential analysis, heterogeneity test, sensitivity analysis, and publication bias assessment were performed. Stata 12.0 and Software R 4.3.1 were utilized for all analyses. Results: This meta-analysis included 7 RCTs with a total of 3,388 participants. The overall analysis revealed that combination therapy of PARP inhibitors and antiangiogenic agents significantly improved PFS (HR = 0.615, 95% CI = 0.517-0.731; 95% PI = 0.379-0.999), but also increased the risk of AEs, including urinary tract infection (RR = 1.500, 95% CI = 1.114-2.021; 95% PI = 0.218-10.346), fatigue (RR = 1.264, 95% CI = 1.141-1.400; 95% PI = 1.012-1.552), headache (RR = 1.868, 95% CI = 1.036-3.369; 95% PI = 0.154-22.642), anorexia (RR = 1.718, 95% CI = 1.320-2.235; 95% PI = 0.050-65.480), and hypertension (RR = 5.009, 95% CI = 1.103-22.744; 95% PI = 0.016-1580.021) compared with PARP inhibitor or antiangiogenic agent monotherapy. Our study has not yet confirmed the benefit of combination therapy on OS in OC patients (HR = 0.885, 95% CI = 0.737-1.063). Additionally, subgroup analyses further showed that combination therapy resulted in an increased risk of AEs, encompassing thrombocytopenia, vomiting, abdominal pain, proteinuria, fatigue, headache, anorexia, and hypertension (all p < 0.05). Conclusion: Our study demonstrated the PFS benefit of combination therapy with PARP inhibitors and antiangiogenic agents in patients with OC. The OS result need to be updated after the original trial data is mature. Clinicians should be vigilant of AEs when administering the combination therapy in clinical practice. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023494482.

Identification of potentially actionable genetic variants in epithelial ovarian cancer: a retrospective cohort study

Ovarian cancer is the most lethal gynecologic malignancy, mainly due to late-stage diagnosis, frequent recurrences, and eventually therapy resistance. To identify potentially actionable genetic variants, sequencing data of 351 Belgian ovarian cancer patients were retrospectively captured from electronic health records. The cohort included 286 (81%) patients with high-grade serous ovarian cancer, 17 (5%) with low-grade serous ovarian cancer, and 48 (14%) with other histotypes. Firstly, an overview of the prevalence and spectrum of the BRCA1/2 variants highlighted germline variants in 4% (11/250) and somatic variants in 11% (37/348) of patients. Secondly, application of a multi-gene panel in 168 tumors revealed a total of 214 variants in 28 genes beyond BRCA1/2 with a median of 1 (IQR, 1-2) genetic variant per patient. The ten most often altered genes were (in descending order): TP53, BRCA1, PIK3CA, BRCA2, KRAS, ERBB2 (HER2), TERT promotor, RB1, PIK3R1 and PTEN. Of note, the genetic landscape vastly differed between the studied histotypes. Finally, using ESCAT the clinical evidence of utility for every genetic variant was scored. Only BRCA1/2 pathogenic variants were classified as tier-I. Nearly all patients (151/168; 90%) had an ESCAT tier-II variant, most frequently in TP53 (74%), PIK3CA (9%) and KRAS (7%). In conclusion, our findings imply that although only a small proportion of genetic variants currently have direct impact on ovarian cancer treatment decisions, other variants could help to identify novel (personalized) treatment options to address the poor prognosis of ovarian cancer, particularly in rare histotypes.

Combined inhibition of HER2 and VEGFR synergistically improves therapeutic efficacy via PI3K-AKT pathway in advanced ovarian cancer

BACKGROUND

Ovarian cancer (OC) is a prevalent malignancy in the female reproductive system, and developing effective targeted therapies for this disease remains challenging. The aim of this study was to use clinically-relevant OC models to evaluate the therapeutic effectiveness of RC48, an antibody-drug conjugate (ADC) targeting HER2, either alone or in combination with the VEGFR inhibitor Cediranib Maleate (CM), for the treatment of advanced OC.

METHODS

OC tumor specimens and cell lines were analyzed to determine HER2 and VEGFR expression by Western blot, immunocytochemistry and immunofluorescence. Moreover, the OC cell lines, cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models were treated with RC48 and/or CM and then subjected to cell proliferation, viability, apoptosis, and tumor growth analyses to evaluate the feasibility of combination therapy for OC both in vitro and in vivo. Additionally, RNA-Seq was performed to investigate the critical mechanism underlying the combination therapy of RC48 and CM.

RESULTS

Our results demonstrated that RC48 alone effectively targeted and inhibited the growth of HER2-positive OC tumors in both cell lines and PDX models. Furthermore, the combination of RC48 and CM synergistically induced tumor regression in human OC cell lines, as well as CDX and PDX models. Mechanistically, we observed that the combination treatment inhibited the growth of OC cells involved inducing apoptosis and suppressing cell motility. RNA-seq analysis provided further mechanistic insights and revealed that co-administration of RC48 and CM downregulated multiple cancer-related pathways, including the AKT/mTOR pathway, cell cycle, and cell proliferation. Notably, our data further confirmed that the PI3K-AKT pathway played a key role in the inhibition of proliferation triggered by combinational treatment of RC48 and CM in OC cells.

CONCLUSIONS

These findings provide a preclinical framework supporting the potential of dual targeting HER2 and VEGFR as a promising therapeutic strategy to improve outcomes in patients with OC.

Cediranib ameliorates portal hypertensive syndrome via inhibition of VEGFR-2 signaling in cirrhotic rats

Portal hypertension (PHT) is a syndrome caused by systemic and portal hemodynamic disturbances with the progression of cirrhosis. However, the exact mechanisms regulating angiogenesis-related responses in PHT remain unclear. Cediranib is a potent inhibitor of vascular endothelial growth factor receptor (VEGFR) tyrosine kinases, exhibiting a greater affinity for VEGFR-2. Liver cirrhosis was induced by common bile duct ligation (BDL) in Sprague-Dawley rats. Sham-operated rats were controls. BDL and sham rats were randomly allocated to receive Cediranib or vehicle after BDL. On the 28th day, portal hypertension related parameters were surveyed. Cediranib treatment could significantly reduce the portal pressure (PP) in BDL rats, while it did not affect the mean arterial pressure (MAP) in sham groups and BDL groups. Cediranib treatment could significantly affect the stroke volume (SV), cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR), superior mesenteric artery (SMA) flow and SMA resistance in BDL groups and BDL with Cediranib groups. Cediranib treatment could improve the mesenteric vascular remodeling and contractility. Cediranib treatment significantly reduced mesenteric vascular density. And phospho-VEGFR-2 was significantly downregulated by Cediranib. On the other hand, phospho-endothelial Nitric Oxide Synthases (phospho-eNOS) expressions were upregulated. Cediranib not only improved splanchnic hemodynamics, extrahepatic vascular remodeling and vasodilation, but also alleviated intrahepatic fibrosis and collagen deposition significantly. Cediranib treatment could reduce intrahepatic angiogenesis between BDL-vehicle and BDL-Cediranib rats. In conclusion, Cediranib could improve extrahepatic hyperdynamic circulation by inhibiting extrahepatic angiogenesis through inhibition of the VEGFR-2 signaling pathway, portal collateral circulation formation, as well as eNOS-mediated vasodilatation and vascular remodeling, and at the same time, Cediranib improved intrahepatic fibrogenesis and angiogenesis, which together alleviate cirrhotic PHT syndrome.

Preclinical Evaluation of Novel Folate Receptor 1-Directed CAR T Cells for Ovarian Cancer

Treatment options for ovarian cancer patients are limited, and a high unmet clinical need remains for targeted and long-lasting, efficient drugs. Genetically modified T cells expressing chimeric antigen receptors (CAR), are promising new drugs that can be directed towards a defined target and have shown efficient, as well as persisting, anti-tumor responses in many patients. We sought to develop novel CAR T cells targeting ovarian cancer and to assess these candidates preclinically. First, we identified potential CAR targets on ovarian cancer samples. We confirmed high and consistent expressions of the tumor-associated antigen FOLR1 on primary ovarian cancer samples. Subsequently, we designed a series of CAR T cell candidates against the identified target and demonstrated their functionality against ovarian cancer cell lines in vitro and in an in vivo xenograft model. Finally, we performed additional in vitro assays recapitulating immune suppressive mechanisms present in solid tumors and developed a process for the automated manufacturing of our CAR T cell candidate. These findings demonstrate the feasibility of anti-FOLR1 CAR T cells for ovarian cancer and potentially other FOLR1-expressing tumors.

Suppression of NBS1 Upregulates CyclinB to Induce Olaparib Sensitivity in Ovarian Cancer

Background: Deficiencies in DNA damage repair responses promote chemotherapy sensitivity of tumor cells. The Nibrin homolog encoding gene Nijmegen Breakage Syndrome 1 (NBS1) is a crucial component of the MRE11-RAD50-NBN complex (MRN complex) and is involved in the response to DNA double-strand breaks (DSBs) repair that has emerged as an attractive strategy to overcome tumor drug resistance, but the functional relationship between NBS1 regulated DNA damage repair and cell cycle checkpoints has not been fully elucidated. Methods: In this study, lentivirus-mediated RNAi was used to construct NBS1-downregulated cells. Flow cytometry, qPCR, and immunohistochemistry were used to explore the regulatory relationship between NBS1 and CyclinB in vivo and in vitro. Results: Our findings suggest that NBS1 deficiency leads to defective homologous recombination repair. Inhibition of NBS1 expression activates CHK1 and CyclinB signaling pathways leading to cell cycle arrest and sensitizes ovarian cancer cells to Olaparib treatment in vitro and in vivo. NBS1-deficient ovarian cancer cells tend to maintain sensitivity to chemotherapeutic drugs through activation of cell cycle checkpoints. Conclusions: NBS1 may be a potential therapeutic target for epithelial ovarian cancer as it plays a role in the regulation of the DNA damage response and cell cycle checkpoints. Suppression of NBS1 upregulates CyclinB to induce Olaparib sensitivity in ovarian cancer.

Dual role of PRDX1 in redox-regulation and tumorigenesis: Past and future

Tumour cells often display an active metabolic profile, leading to the intracellular accumulation of reactive oxygen species. As a member of the peroxidase family, peroxiredoxin 1 (PRDX1) functions generally in protecting against cell damage caused by H2O2. Additionally, PRDX1 plays a role as a molecular chaperone in various malignant tumours, exhibiting either tumour-promoting or tumour-suppressing effects. Currently, PRDX1-targeting drugs have demonstrated in vitro anticancer effects, indicating the potential of PRDX1 as a molecular target. Here we discussed the diverse functions of PRDX1 in tumour biology and provided a comprehensive analysis of the therapeutic potential of targeting PRDX1 signalling across various types of cancer.

The impact of PARP inhibitors in the whole scenario of ovarian cancer management: A systematic review and network meta-analysis

BACKGROUND

Carboplatin is still the cornerstone of the first-line treatment in advanced Epithelial Ovarian Cancer (aEOC) management and the clinical response to platinum-derived agents remains the major predictor of long-term outcomes.

PATIENT AND METHODS

We aimed to identify the best treatment of the aEOC in terms of efficacy and safety, considering all treatment phases. A systematic literature search has been done to compare all treatments in aEOC population. Randomized trials with available survival and safety data published in the 2011-2022 timeframe were enclosed. Only trials reporting the BRCA or HRD (Homologous Recombination Deficiency) status were considered.

DATA EXTRACTION AND SYNTHESIS

A ranking of treatment schedules on the progression-free survival (PFS) endpoint was performed. The random-effect model was used to elaborate and extract data. The Network Meta-Analysis (NMA) by Bayesian model was performed by STATA v17. Data on PFS were extracted in terms of Hazard ratio with relative confidence intervals.

RESULTS

This NMA involved 18 trials for a total of 9105 patients. Within 12 treatment groups, we performed 3 different sensitivity analyses including "all comers" Intention to Treat (ITT) population, BRCA-mutated (BRCAm), and HRD subgroups, respectively. Considering the SUCRA-reported cumulative PFS probabilities, we showed that in the ITT population, the inferred best treatment was niraparib plus bevacizumab with a SUCRA of 96.7. In the BRCAm subgroup, the best SUCRA was for olaparib plus chemotherapy (96,9). The HRD population showed an inferred best treatment for niraparib plus bevacizumab (SUCRA 98,4). Moreover, we reported a cumulative summary of PARPi toxicity, in which different 3-4 grade toxicity profiles were observed, despite the PARPi "class effect" in terms of efficacy.

CONCLUSIONS

Considering all aEOC subgroups, the best therapeutical option was identified as PARPi plus chemotherapy and/or antiangiogenetic agents, suggesting the relevance of combinatory approaches based on molecular profile. This work underlines the potential value of "chemo-free" regimens to prolong the platinum-free interval (PFI).

Complete clinical remission of malignant peritoneal mesothelioma with systemic pemetrexed and bevacizumab in a patient with a BAP1 mutation

Malignant peritoneal mesothelioma (MPeM) is a rare malignancy with historically poor prognosis. Recent research has started to reveal increasingly prevalent genetic mutations seen in this malignancy. Here, we report a case of complete clinical remission of unresectable, metastatic MPeM with systemic chemotherapy. Immunohistochemistry of our patient's malignant cytology sample showed loss of Breast Cancer Gene 1-associated protein-1 expression (BAP1). The patient had synchronous diagnoses of primary squamous cell carcinoma of the anus, benign schwannoma and meningioma. Following the completion of 18 cycles of pemetrexed and bevacizumab, the patient has remained in clinical remission for 8 months. We examine the unusual susceptibility of unresectable MPeM to systemic chemotherapy and attribute susceptibility to the molecular milieu created by mutations in multiple DNA repair pathways. We encourage increased testing for and analysis of mutations in DNA repair pathways to improve future treatment outcomes in this rare malignancy.

Diagnostics and treatment of ovarian cancer in the era of precision medicine - opportunities and challenges

Due to predictions of increasing incidences and deaths from ovarian cancer, this neoplasm is a challenge for modern health care. The advent of NGS technology has made it possible to understand the molecular characteristics of many cancers, including ovarian cancer. The data obtained in research became the basis for the development of molecularly targeted therapies thus leading to the entry of NGS analysis into the diagnostic process of oncological patients. This review presents targeted therapies currently in preclinical or clinical trials, whose promising results offer hope for their use in clinical practice in the future. As more therapeutic options emerge, it will be necessary to modify molecular diagnostic regimens to select the best treatment for a given patient. New biomarkers are needed to predict the success of planned therapy. An important aspect of public health is molecular testing in women with a familial predisposition to ovarian cancer enabling patients to be included in prevention programs. NGS technology, despite its high throughput, poses many challenges, from the quality of the diagnostic material used for testing to the interpretation of results and classification of sequence variants. The article highlights the role of molecular testing in ongoing research and also its role in the diagnostic and therapeutic process in the era of personalized medicine. The spread of genetic testing in high-risk groups, the introduction of more targeted therapies and also the possibility of agnostic therapies could significantly improve the health situation for many women worldwide.

Poly(ADP-ribose) polymerase inhibitors in the treatment landscape of triple-negative breast cancer (TNBC)

OBJECTIVE

Chemotherapy is the mainstay for triple-negative breast cancer (TNBC) patients. Over the years, the use of chemotherapy for these patients has demonstrated many adversities, including toxicity and resistance, which suggested the need to develop novel alternative therapeutic options, such as poly(ADP-ribose) polymerase inhibitors (PARPi). Herein, we provide an overview on PARPi, mechanisms of action and the role of biomarkers in PARPi sensitivity trials, clinical advances in PARPi therapy for TNBC patients based on the most recent studies and findings of clinical trials, and challenges that prevent PARP inhibitors from achieving high efficacy such as resistance and overlapping toxicities with other chemotherapies.

DATA SOURCES

Searching for relevant articles was done using PubMed and Cochrane Library databases by using the keywords including TNBC; chemotherapy; PARPi; BRCA; homologous recombination repair (HRR). Studies had to be published in full-text in English in order to be considered.

DATA SUMMARY

Although PARPi have been used in the treatment of local/metastatic breast malignancies that are HER2 negative and has a germline BRCA mutation, several questions are still to be answered in order to maximize the clinical benefit of PARP inhibitors in TNBC treatment, such as questions related to the optimal use in the neoadjuvant and metastatic settings as well as the best combinations with various chemotherapies.

CONCLUSIONS

PARPi are emerging treatment options for patients with gBRCA1/2 mutations. Determining patients that are most likely to benefit from PARPi and identifying the optimal treatment combinations with high efficacy and fewer side effects are currently ongoing.

Exploration of pyroptosis-associated prognostic gene signature and lncRNA regulatory network in ovarian cancer

Ovarian cancer (OC), is a tumor that poses a serious threat to women's health due to its high mortality rate and bleak prognosis. Pyroptosis, a type of programmed cell death, is important for determining the prognosis of a patient's prognosis for cancer and may represent a novel target for treatment. However, research into how prognosis is impacted by pyroptosis-related genes (PRGs) is poorly understood. In this study, a prognostic model was created using bioinformatic analysis of PRGs in OC. In OC, we discovered 18 pyroptosis regulators that were either up- or down-regulated. By analyzing prognoses, we developed a 9-genes based prognostic model. Each OC patient received a risk score that could be used to categorize them into two subgroups: those with high risk and/or low chance of survival and those with low risk and/or high chance of survival. Functional enrichment and immunoinfiltration analysis indicated that low expression of immune pathways in high-risk group may account for the decrease of survival possibility. In Multivariable cox regression studies, age, clinical stage and the prognostic model were discovered to be independent factors impacting the prognosis for OC. To forecast OC patient survival, a predictive nomogram was developed. Furthermore, we found a correlation between predictive PRGs and clinical stage, indicating that AIM2, CASP3, ZBP1 and CASP8 may play a role in the growth of tumor in OC. After detailed and complete bioinformatics analysis, the lncRNA RP11-186B7.4/hsa-miR-449a/CASP8/AIM2/ZBP1 regulatory axis was identified in OC. Our study may provide a novel approach for prognostic biomarkers and therapeutic targets of OC.

Consensus statements and treatment algorithm to guide clinicians in the selection of maintenance therapy for patients with newly diagnosed, advanced ovarian carcinoma: Results of a Delphi study

INTRODUCTION

Standard treatment of newly diagnosed, advanced ovarian carcinoma (OC) consists of cytoreductive surgery followed by platinum-based chemotherapy with or without bevacizumab. Maintenance therapy with PARP inhibitors and olaparib-bevacizumab has recently shown to significantly improve progression-free survival in the first-line setting. Some practical aspects of maintenance therapy, however, are still poorly defined.

AIM OF THE STUDY

To provide guidance to clinicians in the selection of maintenance therapy for newly diagnosed, advanced ovarian carcinoma.

METHODS

A board of six gynecologic oncologists with expertise in the treatment of OC in Italy convened to address issues related to the new options for maintenance treatment. Based on scientific evidences, the board produced practice-oriented statements. Consensus was reached via a modified Delphi study that involved a panel of 22 experts from across Italy.

RESULTS

Twenty-seven evidence- and consensus-based statements are presented, covering the following areas of interest: use of biomarkers (BRCA mutations and presence of homologous recombination deficiency); timing and outcomes of surgery; selection of patients eligible for bevacizumab; definition of response to treatment; toxicity and contraindications; evidence of synergy of bevacizumab plus PARP inhibitor. Two treatment algorithms are also included, for selecting maintenance therapy based on timing and outcomes of surgery, response to platinum-based chemotherapy and biomarker status. A score for the assessment of response to chemotherapy is proposed, but its validation is ongoing.

CONCLUSIONS

We provide here consensus statements and treatment algorithms to guide clinicians in the selection of appropriate and personalized maintenance therapy in the first-line setting of advanced OC management.

ATAD2 is a driver and a therapeutic target in ovarian cancer that functions by upregulating CENPE

Ovarian cancer is a complex disease associated with multiple genetic and epigenetic alterations. The emergence of treatment resistance in most patients causes ovarian cancer to become incurable, and novel therapies remain necessary. We identified epigenetic regulator ATPase family AAA domain-containing 2 (ATAD2) is overexpressed in ovarian cancer and is associated with increased incidences of metastasis and recurrence. Genetic knockdown of ATAD2 or its pharmacological inhibition via ATAD2 inhibitor BAY-850 suppressed ovarian cancer growth and metastasis in both in vitro and in vivo models. Transcriptome-wide mRNA expression profiling of ovarian cancer cells treated with BAY-850 revealed that ATAD2 inhibition predominantly alters the expression of centromere regulatory genes, particularly centromere protein E (CENPE). In ovarian cancer cells, changes in CENPE expression following ATAD2 inhibition resulted in cell-cycle arrest and apoptosis induction, which led to the suppression of ovarian cancer growth. Pharmacological CENPE inhibition phenotypically recapitulated the cellular changes induced by ATAD2 inhibition, and combined pharmacological inhibition of both ATAD2 and CENPE inhibited ovarian cancer cell growth more potently than inhibition of either alone. Thus, our study identified ATAD2 as regulators of ovarian cancer growth and metastasis that can be targeted either alone or in combination with CENPE inhibitors for effective ovarian cancer therapy.

Exploring the Control of PARP1 Levels in High-Grade Serous Ovarian Cancer

High-grade serous ovarian cancer (HGSOC) is a leading cause of mortality from gynecologic malignancies worldwide. Although a transformative improvement has been shown with the introduction of PARP (poly(ADP-ribose) polymerase) inhibitors, the emergence of resistance to these drugs represents a therapeutic challenge. Hence, expanding our understanding of mechanisms behind the control of PARP1 expression can provide strategic guidance for the translation of novel therapeutic strategies. The Signal Transducer and Activator of Transcription (STAT) family of proteins consists of transcription factors critically involved in the regulation of important cellular functions. Notably, we recently demonstrated that, in cervical cancer cells, STAT1 controls PARP1 levels through multiple mechanisms, possibly involving also STAT3. Here, we tested the hypothesis that a similar mechanism might be operative in HGSOC. To this end, the impact of STAT1/STAT3 modulation on PARP1 expression was assessed in established and primary HGSOC cells, and molecular biology studies proved that STAT1 might act at both transcriptional and post-transcriptional levels to modulate the PARP1 level. Notably, bioinformatics analysis of TCGA databases demonstrated that increased STAT1 mRNA expression levels are associated with a favorable prognosis and with response to chemotherapy in HGSOC patients. Our findings suggest an alternative strategy for targeting HGSOC cells based on their dependency on PARP1.

Angiogenesis inhibitors for the treatment of epithelial ovarian cancer

BACKGROUND

Many women, and other females, with epithelial ovarian cancer (EOC) develop resistance to conventional chemotherapy drugs. Drugs that inhibit angiogenesis (development of new blood vessels), essential for tumour growth, control cancer growth by denying blood supply to tumour nodules.

OBJECTIVES

To compare the effectiveness and toxicities of angiogenesis inhibitors for treatment of epithelial ovarian cancer (EOC).

SEARCH METHODS

We identified randomised controlled trials (RCTs) by searching CENTRAL, MEDLINE and Embase (from 1990 to 30 September 2022). We searched clinical trials registers and contacted investigators of completed and ongoing trials for further information.

SELECTION CRITERIA

RCTs comparing angiogenesis inhibitors with standard chemotherapy, other types of anti-cancer treatment, other angiogenesis inhibitors with or without other treatments, or placebo/no treatment in a maintenance setting, in women with EOC.  DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our outcomes were overall survival (OS), progression-free survival (PFS), quality of life (QoL), adverse events (grade 3 and above) and hypertension (grade 2 and above).

MAIN RESULTS

We identified 50 studies (14,836 participants) for inclusion (including five studies from the previous version of this review): 13 solely in females with newly-diagnosed EOC and 37 in females with recurrent EOC (nine studies in platinum-sensitive EOC; 19 in platinum-resistant EOC; nine with studies with mixed or unclear platinum sensitivity). The main results are presented below.  Newly-diagnosed EOC Bevacizumab, a monoclonal antibody that binds vascular endothelial growth factor (VEGF), given with chemotherapy and continued as maintenance, likely results in little to no difference in OS compared to chemotherapy alone (hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.88 to 1.07; 2 studies, 2776 participants; moderate-certainty evidence). Evidence is very uncertain for PFS (HR 0.82, 95% CI 0.64 to 1.05; 2 studies, 2746 participants; very low-certainty evidence), although the combination results in a slight reduction in global QoL (mean difference (MD) -6.4, 95% CI -8.86 to -3.94; 1 study, 890 participants; high-certainty evidence). The combination likely increases any adverse event (grade ≥ 3) (risk ratio (RR) 1.16, 95% CI 1.07 to 1.26; 1 study, 1485 participants; moderate-certainty evidence) and may result in a large increase in hypertension (grade ≥ 2) (RR 4.27, 95% CI 3.25 to 5.60; 2 studies, 2707 participants; low-certainty evidence). Tyrosine kinase inhibitors (TKIs) to block VEGF receptors (VEGF-R), given with chemotherapy and continued as maintenance, likely result in little to no difference in OS (HR 0.99, 95% CI 0.84 to 1.17; 2 studies, 1451 participants; moderate-certainty evidence) and likely increase PFS slightly (HR 0.88, 95% CI 0.77 to 1.00; 2 studies, 2466 participants; moderate-certainty evidence). The combination likely reduces QoL slightly (MD -1.86, 95% CI -3.46 to -0.26; 1 study, 1340 participants; moderate-certainty evidence), but it increases any adverse event (grade ≥ 3) slightly (RR 1.31, 95% CI 1.11 to 1.55; 1 study, 188 participants; moderate-certainty evidence) and may result in a large increase in hypertension (grade ≥ 3) (RR 6.49, 95% CI 2.02 to 20.87; 1 study, 1352 participants; low-certainty evidence).  Recurrent EOC (platinum-sensitive) Moderate-certainty evidence from three studies (with 1564 participants) indicates that bevacizumab with chemotherapy, and continued as maintenance, likely results in little to no difference in OS (HR 0.90, 95% CI 0.79 to 1.02), but likely improves PFS (HR 0.56, 95% CI 0.50 to 0.63) compared to chemotherapy alone. The combination may result in little to no difference in QoL (MD 0.8, 95% CI -2.11 to 3.71; 1 study, 486 participants; low-certainty evidence), but it increases the rate of any adverse event (grade ≥ 3) slightly (RR 1.11, 1.07 to 1.16; 3 studies, 1538 participants; high-certainty evidence). Hypertension (grade ≥ 3) was more common in arms with bevacizumab (RR 5.82, 95% CI 3.84 to 8.83; 3 studies, 1538 participants).  TKIs with chemotherapy may result in little to no difference in OS (HR 0.86, 95% CI 0.67 to 1.11; 1 study, 282 participants; low-certainty evidence), likely increase PFS (HR 0.56, 95% CI 0.44 to 0.72; 1 study, 282 participants; moderate-certainty evidence), and may have little to no effect on QoL (MD 6.1, 95% CI -0.96 to 13.16; 1 study, 146 participants; low-certainty evidence). Hypertension (grade ≥ 3) was more common with TKIs (RR 3.32, 95% CI 1.21 to 9.10). Recurrent EOC (platinum-resistant) Bevacizumab with chemotherapy and continued as maintenance increases OS (HR 0.73, 95% CI 0.61 to 0.88; 5 studies, 778 participants; high-certainty evidence) and likely results in a large increase in PFS (HR 0.49, 95% CI 0.42 to 0.58; 5 studies, 778 participants; moderate-certainty evidence). The combination may result in a large increase in hypertension (grade ≥ 2) (RR 3.11, 95% CI 1.83 to 5.27; 2 studies, 436 participants; low-certainty evidence). The rate of bowel fistula/perforation (grade ≥ 2) may be slightly higher with bevacizumab (RR 6.89, 95% CI 0.86 to 55.09; 2 studies, 436 participants). Evidence from eight studies suggest TKIs with chemotherapy likely result in little to no difference in OS (HR 0.85, 95% CI 0.68 to 1.08; 940 participants; moderate-certainty evidence), with low-certainty evidence that it may increase PFS (HR 0.70, 95% CI 0.55 to 0.89; 940 participants), and may result in little to no meaningful difference in QoL (MD ranged from -0.19 at 6 weeks to -3.40 at 4 months). The combination increases any adverse event (grade ≥ 3) slightly (RR 1.23, 95% CI 1.02 to 1.49; 3 studies, 402 participants; high-certainty evidence). The effect on bowel fistula/perforation rates is uncertain (RR 2.74, 95% CI 0.77 to 9.75; 5 studies, 557 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Bevacizumab likely improves both OS and PFS in platinum-resistant relapsed EOC. In platinum-sensitive relapsed disease, bevacizumab and TKIs probably improve PFS, but may or may not improve OS. The results for TKIs in platinum-resistant relapsed EOC are similar. The effects on OS or PFS in newly-diagnosed EOC are less certain, with a decrease in QoL and increase in adverse events. Overall adverse events and QoL data were more variably reported than were PFS data. There appears to be a role for anti-angiogenesis treatment, but given the additional treatment burden and economic costs of maintenance treatments, benefits and risks of anti-angiogenesis treatments should be carefully considered.

Combined treatment of disulfiram with PARP inhibitors suppresses ovarian cancer

Introduction

Due to the difficulty of early diagnosis, nearly 70% of ovarian cancer patients are first diagnosed at an advanced stage. Thus, improving current treatment strategies is of great significance for ovarian cancer patients. Fast-developing poly (ADP-ribose) polymerases inhibitors (PARPis) have been beneficial in the treatment of ovarian cancer at different stages of the disease, but PARPis have serious side effects and can result in drug resistance. Using PARPis in combination with other drug therapies could improve the efficacy of PRAPis.In this study, we identified Disulfiram as a potential therapeutic candidate through drug screening and tested its use in combination with PARPis.

Methods

Cytotoxicity tests and colony formation experiments showed that the combination of Disulfiram and PARPis decreased the viability of ovarian cancer cells.

Results

The combination of PARPis with Disulfiram also significantly increased the expression of DNA damage index gH2AX and induced more PARP cleavage. In addition, Disulfiram inhibited the expression of genes associated with the DNA damage repair pathway, indicating that Disulfiram functions through the DNA repair pathway.

Discussion

Based on these findings, we propose that Disulfiram reinforces PARPis activity in ovarian cancer cells by improving drug sensitivity. The combined use of Disulfiram and PARPis provides a novel treatment strategy for patients with ovarian cancer.

Kinase Inhibitors in the Treatment of Ovarian Cancer: Current State and Future Promises

Ovarian cancer is the deadliest gynecological cancer, the high-grade serous ovarian carcinoma (HGSC) being its most common and most aggressive form. Despite the latest therapeutical advancements following the introduction of vascular endothelial growth factor receptor (VEGFR) targeting angiogenesis inhibitors and poly-ADP-ribose-polymerase (PARP) inhibitors to supplement the standard platinum- and taxane-based chemotherapy, the expected overall survival of HGSC patients has not improved significantly from the five-year rate of 42%. This calls for the development and testing of more efficient treatment options. Many oncogenic kinase-signaling pathways are dysregulated in HGSC. Since small-molecule kinase inhibitors have revolutionized the treatment of many solid cancers due to the generality of the increased activation of protein kinases in carcinomas, it is reasonable to evaluate their potential against HGSC. Here, we present the latest concluded and on-going clinical trials on kinase inhibitors in HGSC, as well as the recent work concerning ovarian cancer patient organoids and xenograft models. We discuss the potential of kinase inhibitors as personalized treatments, which would require comprehensive assessment of the biological mechanisms underlying tumor spread and chemoresistance in individual patients, and their connection to tumor genome and transcriptome to establish identifiable subgroups of patients who are most likely to benefit from a given therapy.

A novel combination of niraparib and anlotinib in platinum-resistant ovarian cancer: Efficacy and safety results from the phase II, multi-center ANNIE study

BACKGROUND

Patients with platinum-resistant recurrent ovarian cancer (PROC) face poor prognosis and limited treatment options. Single-agent antiangiogenics and poly (ADP-ribose) polymerase (PARP) inhibitors both show some activities in platinum-resistant diseases. The ANNIE study aimed to evaluate the efficacy and safety of the novel combination of the PARP inhibitor niraparib and the antiangiogenic anlotinib in patients with PROC.

METHODS

ANNIE is a multicentre, single-arm, phase 2 study (ClinicalTrials.gov identifier NCT04376073) conducted at three hospitals in China. Eligible patients had histologically confirmed epithelial ovarian, fallopian tube, or primary peritoneal cancer that recurred within 6 months of last platinum-based chemotherapy. Patients with prior PARP inhibitor exposure were excluded. The enrolled patients received oral niraparib 200 mg or 300 mg (baseline body weight-directed) once daily continuously and anlotinib 10 mg (12 mg before protocol amendment) once daily on days 1-14 of each 21-day cycle until disease progression or intolerable toxicity. The primary endpoint was objective response rate (ORR).

FINDINGS

Between May 22, 2020, and April 22, 2021, 40 patients were enrolled and treated. Thirty-six patients underwent post-baseline tumour assessments. By data cut-off (January 31, 2022), median follow-up was 15.4 months (95% CI 12.6-17.7). Intention-to-treat ORR was 50.0% (95% CI 33.8-66.2), including one complete response and 19 partial responses. Median (95% CI) progression-free survival and overall survival were 9.2 months (7.4-11.9) and 15.3 months (13.9-not evaluable), respectively. Drug-related, grade ≥3 TEAEs were reported in 26 (68%) patients. There were no treatment-related deaths.

INTERPRETATION

Niraparib plus anlotinib showed promising antitumour activity in patients with PROC. This oral combination warrants further investigation as a potential novel, convenient treatment option for patients with PROC.

FUNDING

Zai Lab (Shanghai) Co., Ltd; Jiangsu Chia Tai-Tianqing Pharmaceutical Co., Ltd; the National Natural Science Foundation of China (No. 82102783).

Is there a "low-risk" patient population in advanced epithelial ovarian cancer?: a critical analysis

Ovarian cancer is the leading cause of gynecologic cancer-related death in the United States. Historically, studies have demonstrated that ovarian cancer is a heterogeneous disease with several patient and oncologic characteristics, including BRCA status and residual disease at surgery, known to be predictive of clinical outcomes. However, during the last decade, the discovery and approval of bevacizumab and poly(adenosine diphosphate-ribose) polymerase inhibitors have moved the frontline treatment paradigm beyond platinum-doublet therapy for women with advanced ovarian cancer. Subsequently, investigators have sought to assess the therapeutic efficacy of these agents in women who are considered "high" risk and "low" risk to determine which patients may benefit the most from aggressive therapy and in whom additional treatment may be avoided. We reviewed historic and contemporary definitions of "high-risk" and "low-risk" ovarian cancer and how this has been incorporated into the subset analyses of randomized, clinical trials of therapeutic agents, including bevacizumab and poly(adenosine diphosphate-ribose) polymerase inhibitors. Next, we provided an in-depth discussion of landmark trials for frontline maintenance therapy with bevacizumab and/or poly(adenosine diphosphate-ribose) polymerase inhibitors, focusing on the impact of treatment efficacy according to a "high-risk" and "low-risk" paradigm. Furthermore, we highlighted that recent data have challenged this dichotomous classification, notably from the Gynecologic Oncology Group-0218, ICON7, SOLO-1, and PAOLA-1 trials. Although some studies have suggested that certain populations of women with advanced ovarian cancer may have a more favorable prognosis and be considered "low risk," the risk of progression and death remains unacceptably high in all women. Furthermore, in many cases, those considered the lowest risk have the most treatment benefit from maintenance therapy with poly(adenosine diphosphate-ribose) polymerase inhibitors and/or bevacizumab. From these data, we have advocated that virtually all women with advanced ovarian cancer are high risk and that the use of our most effective therapies in the frontline setting holds promise for potentially curing more patients. Lastly, we critically discuss the practice of using subanalyses in clinical trials, with emphasis that although this practice is important for hypothesis generation, caution must be taken before accepting findings from subanalyses as actual treatment effects.

Emerging perspectives on growth factor metabolic relationships in the ovarian cancer ascites environment

The ascites ecosystem in ovarian cancer is inhabited by complex cell types and is bathed in an environment rich in cytokines, chemokines, and growth factors that directly and indirectly impact metabolism of cancer cells and tumor associated cells. This milieu of malignant ascites, provides a 'rich' environment for the disease to thrive, contributing to every aspect of advanced ovarian cancer, a devastating gynecological cancer with a significant gap in targeted therapeutics. In this perspective we focus our discussions on the 'acellular' constituents of this liquid malignant tumor microenvironment, and how they influence metabolic pathways. Growth factors, chemokines and cytokines are known modulators of metabolism and have been shown to impact nutrient uptake and metabolic flexibility of tumors, yet few studies have explored how their enrichment in malignant ascites of ovarian cancer patients contributes to the metabolic requirements of ascites-resident cells. We focus here on TGF-βs, VEGF and ILs, which are frequently elevated in ovarian cancer ascites and have all been described to have direct or indirect effects on metabolism, often through gene regulation of metabolic enzymes. We summarize what is known, describe gaps in knowledge, and provide examples from other tumor types to infer potential unexplored roles and mechanisms for ovarian cancer. The distribution and variation in acellular ascites components between patients poses both a challenge and opportunity to further understand how the ascites may contribute to disease heterogeneity. The review also highlights opportunities for studies on ascites-derived factors in regulating the ascites metabolic environment that could act as a unique signature in aiding clinical decisions in the future.

Efficacy evaluation of multi-immunotherapy in ovarian cancer: From bench to bed

Ovarian cancer, one of the most common gynecological malignancies, is characterized by high mortality and poor prognosis. Cytoreductive surgery and chemotherapy remain the mainstay of ovarian cancer treatment, and most women experience recurrence after standard care therapies. There is compelling evidence that ovarian cancer is an immunogenic tumor. For example, the accumulation of tumor-infiltrating lymphocytes is associated with increased survival, while increases in immunosuppressive regulatory T cells are correlated with poor clinical outcomes. Therefore, immunotherapies targeting components of the tumor microenvironment have been gradually integrated into the existing treatment options, including immune checkpoint blockade, adoptive cell therapy, and cancer vaccines. Immunotherapies have changed guidelines for maintenance treatment and established a new paradigm in ovarian cancer treatment. Despite single immunotherapies targeting DNA repair mechanisms, immune checkpoints, and angiogenesis bringing inspiring efficacy, only a subset of patients can benefit much from it. Thus, the multi-immunotherapy investigation remains an active area for ovarian cancer treatment. The current review provides an overview of various clinically oriented forms of multi-immunotherapy and explores potentially effective combinational therapies for ovarian cancer.

Targeted Ultrafine Iron Oxide Nanoparticles for Delivery of the Topoisomerase Inhibitor SN38 and Ovarian Cancer Treatment

Ovarian cancer remains a challenge to decrease mortality and improve diagnostic efficiency in gynecological cancers. To develop a delivery system capable of efficient cancer cell targeting and delivering novel efficacious therapeutics, we assembled folic acid (FA) conjugated ultrafine iron oxide nanoparticles (uIONP) with encapsulation of DNA topoisomerase inhibitor SN38, which target ovarian cancer cells with over-expression of folate receptor alpha (FRα) and deliver SN38 to induce apoptosis. The assembled FA-uIONP-SN38 exhibited higher drug loading efficiency than the larger counterparts with core diameters more than 10 nm. The targeting specificity of FA-uIONP-SN38 for SKOV-3 cancer cells was validated, with HEK293 kidney cells and Raw264.7 macrophages as non-targeted cell line control. It was found that more SKOV-3 cancer cells were killed due to apoptosis by FA-uIONP-SN38 at the same SN38 dosages compared with uIONP-SN38 and free SN38, respectively. The delivery of this inhibitor to SKOV-3 cancer cells by FRα-targeted FA-uIONP carrier was enhanced by about 10-folds with less cytotoxicity comparing to the free drug SN38. The developed FA-uIONP-SN38 holds a great potential as a theranostic approach in treating ovarian cancer.

Evolutionary perspectives, heterogeneity and ovarian cancer: a complicated tale from past to present

Ovarian cancer is composed of a complex system of cells best described by features such as clonal evolution, spatial and temporal genetic heterogeneity, and development of drug resistance, thus making it the most lethal gynecologic cancer. Seminal work on cancer as an evolutionary process has a long history; however, recent cost-effective large-scale molecular profiling has started to provide novel insights coupled with the development of mathematical algorithms. In the current review, we have systematically searched for articles that focused on the clonal evolution of ovarian cancer to offer the whole landscape of research that has been done and highlight future research avenues given its characteristic features and connections to evolutionary biology.

Everything Comes with a Price: The Toxicity Profile of DNA-Damage Response Targeting Agents

Simple Summary

DNA damage induces genome instability, which may elicit cancer development. Defects in the DNA repair machinery further enhance cancer predisposition, but can also be exploited as a therapeutic target. Indeed, targeted agents against specific components of DNA repair, such as PARP inhibitors, are employed in various tumor types, while others, such as ATR, CHK1 or WEE1 inhibitors, are in clinical development. Even though these molecules have proven to be effective in different settings, they display several on- and off-target toxicities, shared by the whole pharmacological class or are drug specific. Among these effects, hematological and gastrointestinal toxicities are the most common, while others are less frequent but potentially life-threatening (e.g., myelodysplastic syndromes). Particular caution is needed in the case of combinatorial therapeutic approaches, which are currently being developed in clinical trials. In any case, it is necessary to recognize and properly manage adverse events of these drugs. This review provides a comprehensive overview on the safety profile of DDR-targeting agents, including indications for their management in clinical practice.

Abstract

Targeting the inherent vulnerability of cancer cells with an impaired DNA Damage Repair (DDR) machinery, Poly-ADP-Ribose-Polymerase (PARP) inhibitors have yielded significant results in several tumor types, eventually entering clinical practice for the treatment of ovarian, breast, pancreatic and prostate cancer. More recently, inhibitors of other key components of DNA repair, such as ATR, CHK1 and WEE1, have been developed and are currently under investigation in clinical trials. The inhibition of DDR inevitably induces on-target and off-target adverse events. Hematological and gastrointestinal toxicities as well as fatigue are common with all DDR-targeting agents, while other adverse events are drug specific, such as hypertension with niraparib and transaminase elevation with rucaparib. Cases of pneumonitis and secondary hematological malignancies have been reported with PARP inhibitors and, despite being overly rare, they deserve particular attention due to their severity. Safety also represents a crucial issue for the development of combination regimens incorporating DDR-targeting agents with other treatments, such as chemotherapy, anti-angiogenics or immunotherapy. As such, overlapping and cumulative toxicities should be considered, especially when more than two classes of drugs are combined. Here, we review the safety profile of DDR-targeting agents when used as single agents or in combination and we provide principles of toxicity management.

Dual targeting, a new strategy for novel PARP inhibitor discovery

As a hallmark for cancer treatment, PARP inhibitors can effectively kill tumor cells with a mechanism termed as synthetic lethality, and are used to treat various cancers including ovarian, breast, prostate, pancreatic and others with DNA repair defects. However, along with the clinical trials progressing, the limitations of PARP-1 inhibitors became apparent such as limited activity and indications. Studies have shown that a molecule that is able to simultaneously restrict two or more targets involving in tumors is more effective in preventing and treating cancers due to the enhancing synergies. In order to make up for the shortcomings of PARP inhibitors, reduce the development cost and overcome the pharmacokinetic defects, multiple works were carried out to construct dual targeting PARP inhibitors for cancer therapy. Herein, they were summarized briefly.

PARP Inhibitors in Pancreatic Cancer

ABSTRACT

Despite representing only 5% of all annual cancer diagnoses in the United States, pancreatic cancer is projected to become the second leading cause of cancer-related death within the next 10 years. Progress in the treatment of advanced pancreatic cancer has been slow. Systemic therapies rely on combination cytotoxic agents, with limited options at progression. Recently, poly(ADP-ribose) polymerase inhibitors have demonstrated clinical activity in patients with advanced pancreatic cancer and pathogenic variants in BRCA1, BRCA2, and PALB2. In this review, we discuss the development of poly(ADP-ribose) polymerase inhibitors in pancreatic cancer, relevant clinical trials, and future directions.