BACKGROUND: Poly adenosine-diphosphate-ribose polymerase (PARP) inhibitors (PARPi) have been approved to act as first-line maintenance (FL-M) therapy and as platinum-sensitive recurrent maintenance (PSR-M) therapy for ovarian cancer in China for >5 years. Herein, we have analyzed the clinical-application characteristics of olaparib and niraparib in ovarian cancer-maintenance therapy in a real-world setting to strengthen our understanding and promote their rational usage. METHODS: A retrospective chart review identified patients with newly diagnosed or platinum-sensitive recurrent ovarian cancer, who received olaparib or niraparib as maintenance therapy at Sichuan Cancer Hospital between August 1, 2018, and December 31, 2021. Patient medical records were reviewed. We grouped and analyzed patients based on the type of PARPi they used (the olaparib group and the niraparib group) and the line of PARPi maintenance therapy (the FL-M setting and the PSR-M setting). The primary endpoint was the 24-month progression-free survival (PFS) rate. RESULTS: In total, 131 patients (olaparib: n = 67, 51.1%; niraparib: n = 64, 48.9%) were enrolled. Breast cancer susceptibility genes ( BRCA ) mutations ( BRCA m) were significantly less common in the niraparib group than in the olaparib group [9.4% (6/64) vs . 62.7% (42/67), P <0.001], especially in the FL-M setting [10.4% (5/48) vs . 91.4% (32/35), P <0.001]. The 24-month progression-free survival (PFS) rates in the FL-M and PSR-M settings were 60.4% and 45.7%, respectively. In patients with BRCA m, the 24-month PFS rates in the FL-M and PSR-M settings were 62.2% and 72.7%, respectively. CONCLUSIONS Olaparib and niraparib were effective in patients with ovarian cancer without any new safety signals except for skin pigmentation. In patients with BRCA m, the 24-month PFS of the PARPi used in the PSR-M setting was even higher than that used in the FL-M setting.
Humans ; Female ; Ovarian Neoplasms/drug therapy* ; Piperazines/therapeutic use* ; Middle Aged ; Retrospective Studies ; Phthalazines/therapeutic use* ; Piperidines/therapeutic use* ; Indazoles/therapeutic use* ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Adult ; Aged ; China ; Neoplasm Recurrence, Local/drug therapy* ; Progression-Free Survival

Poly(ADP-ribose) polymerase (PARP) inhibitors (PARPis) have emerged as critical agents for cancer therapy. By inhibiting the catalytic activity of PARP enzymes and trapping them in the DNA, PARPis disrupt DNA repair, ultimately leading to cell death, particularly in cancer cells with homologous recombination repair deficiencies, such as those harboring BRCA mutations. This review delves into the mechanisms of action of PARPis in anticancer treatments, including the inhibition of DNA repair, synthetic lethality, and replication stress. Furthermore, the clinical applications of PARPis in various cancers and their adverse effects as well as their combinations with other therapies and the mechanisms underlying resistance are summarized. This review provides comprehensive insights into the role and mechanisms of PARP and PARPis in DNA repair, with a particular focus on the potential of PARPi-based therapies in precision medicine for cancer treatment.
Humans ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Neoplasms/genetics* ; DNA Repair/drug effects* ; Animals ; Antineoplastic Agents/therapeutic use*

Although olaparib has demonstrated substantial clinical benefits as maintenance therapy in BRCA mutation-carrying women with newly diagnosed advanced ovarian cancer, its effectiveness in patients without BRCA mutations remains poorly investigated. This study aims to provide the first evidence on the efficacy of mono-olaparib maintenance therapy in such context. Using real-world data from 11 high-volume tertiary care centers in China, a retrospective cohort study was conducted to assess the efficacy and safety of olaparib as first-line maintenance therapy in patients with BRCA wild-type ovarian cancer. The primary objective was 1-year progression-free survival rate. Safety was also evaluated. Fifty patients with a median age of 54 years were included, and all of them tested negative for BRCA mutations but positive for homologous recombination deficiency (HRD). The 1-year PFS rate was 75.2% (95% CI, 63.4 to 89.2), and the median PFS was 21.0 months (95% CI, 13.8 to 28.2). All the patients received olaparib at a starting dose of 300 mg twice daily, and none experienced serious adverse events (AEs). Eight (16%) patients had dose adjustment, but none discontinued olaparib treatment due to AEs. We provide the first evidence that mono-olaparib could be a safe and effective maintenance treatment option for patients newly diagnosed with HRD-positive/BRCA wild-type ovarian cancer.
Humans ; Female ; Phthalazines/adverse effects* ; Piperazines/administration & dosage* ; Middle Aged ; Ovarian Neoplasms/genetics* ; Retrospective Studies ; Adult ; Aged ; Poly(ADP-ribose) Polymerase Inhibitors/administration & dosage* ; China ; Maintenance Chemotherapy ; BRCA2 Protein/genetics* ; Antineoplastic Agents/adverse effects* ; Progression-Free Survival ; BRCA1 Protein/genetics*

Poly ADP-ribose polymerase inhibitors (PARPi), which approved in recent years, are recommended for ovarian cancer, breast cancer, pancreatic cancer, prostate cancer and other cancers by The National Comprehensive Cancer Network (NCCN) and Chinese Society of Clinical Oncology (CSCO) guidelines. Because most of PARPi are metabolized by cytochrome P450 enzyme system, there are extensive interactions with other drugs commonly used in cancer patients. By setting up a consensus working group including pharmaceutical experts, clinical experts and methodology experts, this paper forms a consensus according to the following steps: determine clinical problems, data retrieval and evaluation, Delphi method to form recommendations, finally formation expert opinion on PARPi interaction management. This paper will provide practical reference for clinical medical staff.
Male ; Female ; Humans ; Poly(ADP-ribose) Polymerase Inhibitors/pharmacology* ; Consensus ; Ovarian Neoplasms/drug therapy* ; Drug Interactions ; Adenosine Diphosphate Ribose/therapeutic use*

The common adverse reactions caused by poly (ADP-ribose) polymerase (PARP) inhibitors include hematological toxicity, gastrointestinal toxicity and fatigue. The main prevention and treatment of hematological toxicity include: regular blood tests, referral to hematology department when routine treatment is ineffective, and being alert of myelodysplastic syndrome/acute myeloid leukemia. The key points to deal with gastrointestinal toxicity include: taking medicine at the right time, light diet, appropriate amount of drinking water, timely symptomatic treatment, prevention of expected nausea and vomiting, and so on. For fatigue, full assessment should be completed before treatment because the causes of fatigue are various; the management includes massage therapy, psychosocial interventions and drugs such as methylphenidate and Panax quinquefolius according to the severity. In addition, niraparib and fluzoparib can cause hypertension, hypertensive crisis and palpitation. Blood pressure and heart rate monitoring, timely symptomatic treatment, and multidisciplinary consultation should be taken if necessary. When cough and dyspnea occur, high resolution CT and bronchoscopy should be performed to exclude pneumonia. If necessary, PARP inhibitors should be stopped, and glucocorticoid and antimicrobial therapy should be given. Finally, more attention should be paid to drug interaction management, patient self-management and regular monitoring to minimize the risk and harm of adverse reactions of PARP inhibitors.
Humans ; Poly(ADP-ribose) Polymerase Inhibitors/adverse effects* ; Phthalazines/pharmacology* ; Poly(ADP-ribose) Polymerases ; Fatigue/drug therapy*

OBJECTIVES: To investigate the effect of borneol on cutaneous toxicity of gilteritinib and to explore possible compounds that can intervene with the cutaneous toxicity. METHODS: C57BL/6J male mice were given gilteritinib by continuous gavage for 28 d and the damage to keratinocytes in the skin tissues was observed with hematoxylin and eosin (HE) staining, TUNEL assay and immunohistochemistry. Human keratinocytes HaCaT were treated with gilteritinib, and cell death and morphological changes were examined by SRB staining and microscopy; apoptosis of HaCaT cells was examined by Western blotting, flow cytometry with propidium iodide/AnnexinⅤ double staining and immunofluorescence; the accumulation of cellular reactive oxygen species (ROS) was examined by flow cytometry with DCFH-DA. Compounds that can effectively intervene the cutaneous toxicity of gilteritinib were screened from a natural compound library using SRB method, and the intervention effect of borneol on gilteritinib cutaneous toxicity was further investigated in HaCaT cells and C57BL/6J male mice. RESULTS: In vivo studies showed pathological changes in the skin with apoptosis of keratinocytes in the stratum spinosum and stratum granulosum in the modeling group. Invitro studies showed apoptosis of HaCaT cells, significant up-regulation of cleaved poly (ADP-ribose) polymerase (c-PARP) and gamma-H2A histone family member X (γ-H2AX) levels, and increased accumulation of ROS in gilteritinib-modeled skin keratinocytes compared with controls. Screening of the natural compound library revealed that borneol showed excellent intervention effects on the death of HaCaT cells. In vitro, cell apoptosis was significantly reduced in the borneol+gilteritinib group compared to the gilteritinib control group. The levels of c-PARP, γ-H2AX and ROS in cells were significantly decreased. In vivo, borneol alleviated gilteritinib-induced skin pathological changes and skin cell apoptosis in mice. CONCLUSIONS Gilteritinib induces keratinocytes apoptosis by causing intracellular ROS accumulation, resulting in cutaneous toxicity. Borneol can ameliorate the cutaneous toxicity of gilteritinib by reducing the accumulation of ROS and apoptosis of keratinocytes in the skin tissue.
Male ; Humans ; Animals ; Mice ; Reactive Oxygen Species/metabolism* ; Poly(ADP-ribose) Polymerase Inhibitors/pharmacology* ; Mice, Inbred C57BL ; Apoptosis ; Poly(ADP-ribose) Polymerases/metabolism*

OBJECTIVE: To explore the combined pro-apoptosis effect of HSP90 inhibitor BIIB021 and chloroquine (CQ) in chronic myeloid leukemia (CML) cells bearing T315I mutation and its mechanism. METHODS: The p210-T315I cells were divided into 4 groups by different treatment: control, BIIB021, CQ, and BIIB021 + CQ. After treated with BIIB021 or/and CQ for 24 hours, Annexin V/PI binding assay was used to detect apoptosis rates of CML cells. DAPI staining was used to observe nuclear fragmentation, and Western blot was used to detect the expression of caspase 3, PARP (apoptosis related proteins) and p62, LC3-I/II (autophagy related proteins). P210-T315I cells were inoculated subcutaneously into mice and CML mouse models were established. The mice in treatment groups were injected with BIIB021 and/or CQ while mice in control group were treated with PBS and normal saline. The tumor volume of mice was measured every 4 days, and protein level of cleaved-caspase 3 and LC3-II in tumor tissue were detected by immunohistochemistry. RESULTS: The results showed that BIIB021 induced apoptosis of CML cells in a dose-dependent manner ( r=0.91). CQ could enhance the apoptosis-inducing effect of BIIB021. Flow cytometry analysis results showed that the apoptosis rate of p210-T315I cells in combination group was higher than that in BIIB021 or CQ only group (P<0.05). DAPI staining showed nuclear fragmentation in combination group could be observed more obviously. Western blot analysis showed that BIIB021 could induce LC3-I to convert to LC3-II and decrease p62 protein levels (P<0.05). Moreover, the combination group had higher expression of LC3-II, p62 (P<0.05), activated PARP and activated caspase 3 than BIIB021 only group (P<0.05). Besides, experiment in vivo showed the mean tumor volume in co-treatment group was lower than that in single drug group (P<0.01). Immunohistochemistry of tumor tissue also showed the protein level of cleaved-caspase 3 and LC3-II in combined group was higher than that in BIIB021 only group. CONCLUSION HSP90 inhibitor BIIB021 induced significant apoptosis of CML cells bearing T315I both in vivo and in vitro. CQ can enhance this effect probably by autophagy inhibition.
Adenine/analogs & derivatives* ; Animals ; Apoptosis ; Autophagy ; Caspase 3/metabolism* ; Cell Line, Tumor ; Chloroquine/therapeutic use* ; Fusion Proteins, bcr-abl/pharmacology* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Mice ; Mutation ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Pyridines

OBJECTIVE: To investigate the effect of dihydroartemisinin (DHA) combined with arsenic trioxide (ATO) on the viability and apoptosis of acute myeloid leukemia (AML) FLT3-ITD mutant cell line MOLM13 and its mechanism. METHODS: MOLM13 cells were treated with DHA or ATO alone or in combination. The viability of MOLM13 cells was detected by CCK-8 assay, cell proliferation was observed by colony formation assay, cell apoptosis and reactive oxygen species (ROS) level were measured by flow cytometry, and the expression levels of proteins related to apoptosis were detected by Western blot. RESULTS: Compared with the control group, treatment with DHA and ATO alone or in combination could inhibit cell proliferation, activate ROS formation, and finally induce cell apoptosis. DHA in combination with ATO produced a synergistic effect. Western blot analysis showed that DHA combined with ATO could significantly upregulate the level of c-PARP and activate apoptosis via inhibition of Mcl-1 and FLT3-ITD. CONCLUSION DHA combined with ATO induces the apoptosis of FLT3-ITD AML cell line MOLM13 by inhibiting Mcl-1 pathway and activating FLT3-ITD protein degradation.
Apoptosis ; Arsenic Trioxide/therapeutic use* ; Artemisinins/therapeutic use* ; Cell Line, Tumor ; Humans ; Leukemia, Myeloid, Acute/drug therapy* ; Myeloid Cell Leukemia Sequence 1 Protein ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Reactive Oxygen Species/therapeutic use* ; Sincalide/therapeutic use* ; fms-Like Tyrosine Kinase 3

Objective: To determine the effect of tumor metastasis-associated gene 1 (MTA1) on the sensitivity of HeLa cells to radiotherapy, and to clarify its molecular mechanism. Methods: The transcriptome differences between MTA1 knocked down Hela cells and control cells were analyzed, and the differentially expressed genes (DEGs) was used to perform Gene-Set Enrichment Analysis (GSEA) and Gene Ontology (GO) cluster analysis. Flow cytometry was used to detect apoptosis in MTA1-overexpressed HeLa cells and control cells before and after 10 Gy X-ray irradiation. Cloning formation assay and real-time cellular analysis (RTCA) were used to monitor the cell proliferation before and after 2 Gy X-ray irradiation. To dissect the underlying molecular mechanisms of MTA1 affecting the sensitivity of radiotherapy, the proteins encoded by the DEGs were selected to construct a protein-protein interaction network, the expression of γ-H2AX was detected by immunofluorescence assay, and the expression levels of γ-H2AX, β-CHK2, PARP and cleaved caspase 3 were measured by western blot. Results: By transcriptome sequencing analysis, we obtained 649 DEGs, of which 402 genes were up-regulated in MTA1 knockdown HeLa cells and 247 genes were down-regulated. GSEA results showed that DEGs associated with MTA1 were significantly enriched in cellular responses to DNA damage repair processes. The results of flow cytometry showed that the apoptosis rate of MTA1 over-expression group (15.67±0.81)% after 10 Gy X-ray irradiation was significantly lower than that of the control group [(40.27±2.73)%, P<0.001]. After 2 Gy X-ray irradiation, the proliferation capacity of HeLa cells overexpressing MTA1 was higher than that of control cells (P=0.024). The numbers of colon in MTA1 over-expression group before and after 2 Gy X-ray irradiation were (176±7) and (137±7) respectively, higher than (134±4) and (75±4) in control HeLa cells (P<0.05). The results of immunofluorescence assay showed that there was no significant expression of γ-H2AX in MTA1 overexpressed and control HeLa cells without X-ray irradiation. Western blot results showed that the expression level of β-CHK2 in MTA1-overexpressing HeLa cells (1.04±0.06) was higher than that in control HeLa cells (0.58±0.25, P=0.036) after 10 Gy X-ray irradiation. The expression levels of γ-H2AX, PARP, and cleaved caspase 3 were 0.52±0.13, 0.52±0.22, and 0.63±0.18, respectively, in HeLa cells overexpressing MTA1, which were lower than 0.87±0.06, 0.78±0.12 and 0.90±0.12 in control cells (P>0.05). Conclusions: This study showed that MTA1 is significantly associated with radiosensitivity in cervical cancer HeLa cells. MTA1 over-expression obviously reduces the sensitivity of cervical cancer cells to X-ray irradiation. Mechanism studies initially indicate that MTA1 reduces the radiosensitivity of cervical cancer cells by inhibiting cleaved caspase 3 to suppress apoptosis and increasing β-CHK2 to promote DNA repair.
Apoptosis/genetics* ; Caspase 3/metabolism* ; Female ; HeLa Cells ; Humans ; Poly(ADP-ribose) Polymerase Inhibitors ; Radiation Tolerance/genetics* ; Repressor Proteins/metabolism* ; Trans-Activators/metabolism* ; Uterine Cervical Neoplasms/radiotherapy*

OBJECTIVE: To investigate the role of tumor necrosis factor receptor-associated factor 6 (TRAF6) in regulating Bacillus Calmette-Guérin (BCG)-induced macrophage apoptosis. METHODS: The expression of TRAF6 in peripheral blood samples of 50 patients with active tuberculosis (TB) and 50 healthy individuals were detected using quantitative real-time PCR (qPCR). RAW264.7 macrophages were infected with BCG at different MOI and for different lengths of time, and the changes in expressions of Caspase 3 and TRAF6 were detected with Western blotting and qPCR. In a RAW264.7 cell model of BCG infection with TRAF6 knockdown established using RNA interference technique, the bacterial load was measured and cell apoptotic rate and mitochondrial membrane potential (MMP) were determined with flow cytometry. The expression levels of TRAF6, Caspase 3, PARP, BAX and Bcl-2 in the cells were detected using Western blotting, and the expressions of TRAF6 and Caspase 3 were also examined with immunofluorescence assay. RESULTS: The expression of TRAF6 was significantly upregulated in the peripheral blood of patients with active TB as compared with healthy subjects (P < 0.001). In RAW264.7 cells, BCG infection significantly increased the expressions of Caspase 3 and TRAF6, which were the highest in cells infected for 18 h and at the MOI of 15. TRAF6 knockdown caused a significant increase of bacterial load in BCG-infected macrophages (P=0.05), lowered the cell apoptotic rate (P < 0.001) and reduced the expressions of Caspase 3 (P=0.002) and PARP (P < 0.001). BCG-infected RAW264.7 cells showed a significantly increased MMP (P < 0.001), which was lowered by TRAF6 knockdown (P < 0.001); the cells with both TRAF6 knockdown and BCG infection showed a lowered BAX expression (P=0.005) and an increased expression of Bcl-2 (P=0.04). CONCLUSION TRAF6 promotes BCG-induced macrophage apoptosis by regulating the intrinsic apoptosis pathway.
Apoptosis ; BCG Vaccine ; Caspase 3/metabolism* ; Humans ; Intracellular Signaling Peptides and Proteins ; Macrophages ; Mycobacterium bovis/metabolism* ; Poly(ADP-ribose) Polymerase Inhibitors ; TNF Receptor-Associated Factor 6/metabolism* ; bcl-2-Associated X Protein/metabolism*