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 DNA damage response is critical for cells to maintain genome stability and survival. In this review, we discuss approaches to targeting critical elements of the DNA damage response for radiosensitization and chemosensitization. In addition, we also discuss strategies for targeting DNA damage response and DNA repair defects in cancer cells for synthetic lethality.
Antineoplastic Agents ; therapeutic use ; Cell Death ; DNA Damage ; genetics ; DNA Repair ; genetics ; Dose-Response Relationship, Radiation ; Drug Resistance, Neoplasm ; Genomic Instability ; Humans ; Neoplasms ; drug therapy ; genetics ; pathology ; radiotherapy ; Poly(ADP-ribose) Polymerase Inhibitors ; Poly(ADP-ribose) Polymerases ; pharmacology ; Radiation Dosage

BACKGROUNDPoly (ADP-ribose) polymerase (PARP) has been proposed to play an important role in the pathogenesis of heart ischaemia/reperfusion (I/R) injury. 3,4-dihydro-5-[4-(1-piperidinyl)butoxy]-1(2H)-isoquinolinone (DPQ), a potent PARP inhibitor, has cardiac protective effects. Because the underlying mechanisms are not understood, we investigated the effect of DPQ on heart I/R injury and its mechanisms.

METHODSStudies were performed with I/R rats' hearts. DPQ was used to inhibit the activation of PARP. Cardiac function and cellular apoptosis were assessed. The activation of PARP, transcription factor nuclear factor-kappaB (NF-κB), intercellular adhesion molecule-1 (ICAM-1), cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9) were evaluated. We also evaluated expression of Akt and two of its downstream targets, glycogen synthase kinase-3β (GSK-3β) and forkhead transcription factor FOXO3a.

RESULTSAdministration of DPQ significantly decreased the activation of PARP and cellular apoptosis from (35 ± 5)% to (20 ± 4)% and simultaneously improved the cardiac function. DPQ reduced the expressions of NF-κB, ICAM-1, COX-2 and MMP-9 in rat heart and facilitated the activations of phosphor-Akt, phosphor-GSK-3β and phosphor-FOXO3a.

CONCLUSIONThe protective effects of DPQ were associated with the suppression of inflammation and the activation of the Akt signalling pathways suggesting that the inhibition of poly (ADP-ribose) polymerase reduced heart I/R injury in rats.

Animals ; Blotting, Western ; Enzyme Inhibitors ; therapeutic use ; Female ; Isoquinolines ; therapeutic use ; Myocardial Reperfusion Injury ; drug therapy ; Piperidines ; therapeutic use ; Poly(ADP-ribose) Polymerase Inhibitors ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Rats, Wistar

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

BACKGROUNDBrain dysfunction is a frequent complication of sepsis, usually defined as sepsis-associated encephalopathy (SAE). Although the Notch signaling pathway has been proven to be involved in both ischemia and neuronal proliferation, its role in SAE is still unknown. Here, the effect of the Notch signaling pathway involved γ-secretase inhibitor DAPT on SAE in septic rats was investigated in a cecal ligation and puncture (CLP) model.

METHODSFifty-nine Sprague-Dawley rats were randomly divided into four groups, with the septic group receiving the CLP operation. Twenty-four hours after CLP or sham treatment, rats were sacrificed and their hippocampus was harvested for Western blot analysis. TNF-α expression was determined using an enzyme-linked immunosorbent assay (ELISA) kit. Neuronal apoptosis was assessed by TUNEL staining, and neuronal cell death was detected by H&E staining. Finally, a novel object recognition experiment was used to evaluate memory impairment.

RESULTSOur data showed that sepsis can increase the expression of hippocampal Notch receptor intracellular domain (NICD) and poly (adenosine diphosphate [ADP]-ribose) polymerase-1 (PARP-1), as well as the inflammatory response, neuronal apoptosis, neuronal death, and memory dysfunction in rats. The γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butyl ester (DAPT) can significantly decrease the level of NICD and PARP-1, reduce hippocampal neuronal apoptosis and death, attenuate TNF-α release and rescue cognitive impairment caused by CLP.

CONCLUSIONThe neuroprotective effect of DAPT on neuronal death and memory impairment in septic rats, which could be a new therapeutic approach for treating SAE in the future.

Amyloid Precursor Protein Secretases ; antagonists & inhibitors ; Animals ; Apoptosis ; drug effects ; Dipeptides ; therapeutic use ; Hippocampus ; drug effects ; metabolism ; Male ; Neurons ; cytology ; drug effects ; Neuroprotective Agents ; Poly (ADP-Ribose) Polymerase-1 ; Poly(ADP-ribose) Polymerases ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Notch ; metabolism ; Sepsis ; complications ; Sepsis-Associated Encephalopathy ; drug therapy ; enzymology ; Signal Transduction ; drug effects

The poly(ADP-ribose) polymerases (PARPs) is an important group of enzymes in DNA repair pathways, especially the base excision repair (BER) for DNA single-strand breaks (SSBs) repair. Inhibition of PARP in DNA repair-defective tumors (like those with BRAC1/2 mutations) can lead to cell death and genomic instability, what is so called "synthetic lethality". Currently, PARP inhibitors combined with cytotoxic chemotherapeutic agents in the treatment of BRCA-1/2 deficient cancers are in the clinical development. In this review, we will be focused on the development of combination application of PARP inhibitors with other anticancer agents in clinical trials.
Animals ; Antineoplastic Agents ; therapeutic use ; Benzimidazoles ; therapeutic use ; Breast Neoplasms ; drug therapy ; genetics ; DNA Repair ; Drug Therapy, Combination ; Enzyme Inhibitors ; therapeutic use ; Female ; Humans ; Indoles ; therapeutic use ; Melanoma ; drug therapy ; Mutation ; Ovarian Neoplasms ; drug therapy ; genetics ; Phthalazines ; therapeutic use ; Piperazines ; therapeutic use ; Poly(ADP-ribose) Polymerase Inhibitors

PARP is an important protein in DNA repair pathways especially the base excision repair (BER). BER is involved in DNA repair of single strand breaks (SSBs). If BER is impaired, inhibiting poly(ADP-ribose) polymerase (PARP), SSBs accumulate and become double stand breaks (DSBs). The cells with increasing number of DSBs become more dependent on other repair pathways, mainly the homologous recombination (HR) and the nonhomologous end joining. Patients with defective HR, like BRCA-deficient cell lines, are even more susceptible to impairment of the BER pathway. Inhibitors of PARP preferentially kill cancer cells in BRCA-mutation cancer cell lines over normal cells. Also, PARP inhibitors increase cytotoxicity by inhibiting repair in the presence of chemotherapies that induces SSBs. These two principles have been tested clinically. Over the last few years, excitement over this class of agents has escalated due to reported activity as single agent in BRCA1- or BRCA2-associated ovarian or breast cancers, and in combination with chemotherapy in triple negative breast cancer. This review covers the current results of clinical trials testing those two principles. It also evaluates future directions for the field of PARP inhibitor development.
Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Benzamides ; administration & dosage ; Benzimidazoles ; administration & dosage ; Breast Neoplasms ; drug therapy ; enzymology ; genetics ; DNA Breaks, Double-Stranded ; DNA Breaks, Single-Stranded ; DNA End-Joining Repair ; DNA Repair ; Enzyme Inhibitors ; therapeutic use ; Female ; Genes, BRCA1 ; Genes, BRCA2 ; Homologous Recombination ; Humans ; Mutation ; Ovarian Neoplasms ; drug therapy ; enzymology ; genetics ; Phthalazines ; administration & dosage ; Piperazines ; administration & dosage ; Poly(ADP-ribose) Polymerase Inhibitors ; Poly(ADP-ribose) Polymerases ; metabolism

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

This study aims to investigate the effect of ethoxysanguinarine(Eth) on cisplatin(DDP)-resistant human gastric cancer cells and decipher the underlying mechanism. The human gastric cancer cell line SGC7901 and the DDP-resistant cell line SGC7901/DDP were used as the cell models. Western blot was employed to determine the expression levels of multidrug resistance-related proteins, and methyl thiazolyl tetrazolium(MTT) assay to detect the proliferation of SGC7901 and SGC7901/DDP cells exposed to DDP. After treatment with different concentrations of Eth, the proliferation of SGC7901 and SGC7901/DDP cells was detected by MTT assay, trypan blue exclusion assay, colony formation assay, and high-content imaging and analysis system. The apoptosis of SGC7901/DDP cells was detected by flow cytometry with Annexin V-FITC/PI staining. GFP-LC3 transfection was carried out to detect the effect of Eth on the autophagy of SGC7901/DDP cells. The expression levels of the multidrug resistance-related protein P-glycoprotein(P-gp), the apoptosis-related proteins [caspase-9, caspase-3, and poly(ADP-ribose) polymerase(PARP)], the autophagy-related protein light chain 3-Ⅱ(LC3-Ⅱ), the key effectors [mammalian target of rapamycin(mTOR), 70 kDa ribosomal protein S6 kinase(P70 S6 K), and 4 E binding protein 1(4 E-BP1)] of the mammalian target of rapamycin complex 1(mTORC1) signaling pathway, cancerous inhibitor of protein phosphatase 2A(CIP2A), and protein kinase B(Akt) were measured by Western blot. The mRNA level of CIP2A in the SGC7901/DDP cells exposed to Eth for 24 h was analyzed by RT-qPCR. After SGC7901/DDP cells were transfected with CIP2A expression vector pcDNA3.1-HA-CIP2A and treated with different concentrations of Eth, MTT assay was used to determine the prolife-ration of SGC7901/DDP cells and Western blot to detect the expression levels of related proteins. The interaction sites of Eth and CIP2A were predicted by molecular docking. The affinity between Eth and CIP2A was determined by drug affinity responsive target stability(DARTS) assay. The pharmacokinetic properties and drug-like activity of Eth were predicted by SwissADME. The results indicated that SGC7901/DDP cells were more sensitive to Eth than SGC7901 cells. Eth significantly inhibited proliferation and colony formation and changed the morphology, roundness, and area of SGC7901/DDP cells. Eth treatment caused the nucleus shrinking and significantly increased the apoptosis rate of the cells. Furthermore, Eth down-regulated the expression of caspase-9 and caspase-3 precursors and promoted the cleavage of PARP, which suggested that Eth induced the apoptosis of SGC7901/DDP cells. The GFP-LC3 in Eth-treated cells showed speckled aggregation. The up-regulated expression of LC3-Ⅱ by Eth indicated that Eth activated the autophagy of SGC7901/DDP cells. Eth down-regulated the expression of P-gp, the phosphorylation of mTOR, P70 S6K, and 4E-BP1, the expression of CIP2A, and the phosphorylation of Akt. Additionally, it increased the activity of PP2A, and had no significant effect on the expression of CIP2A in SGC7901/DDP cells. CIP2A overexpression antagonized the inhibition of cell proliferation and the activation of autophagy by Eth. Molecular docking suggested that Eth bound to CIP2A. The results of DARTS assay further proved the above binding effect. Eth has potential drug-like activity. The above results demonstrated that Eth inhibited the proliferation, induced the apoptosis, and activated the autophagy of SGC7901/DDP cells by targeting CIP2A and then down-regulating PP2A/mTORC1 signaling pathway. This study provided a new target for the treatment of cisplatin-resistant gastric cancer.
Humans ; Cisplatin/therapeutic use* ; Caspase 9/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Caspase 3/metabolism* ; Stomach Neoplasms/metabolism* ; Drug Resistance, Neoplasm ; Antineoplastic Agents/therapeutic use* ; Molecular Docking Simulation ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Autophagy ; Apoptosis ; Cell Proliferation ; Apoptosis Regulatory Proteins/metabolism* ; Mechanistic Target of Rapamycin Complex 1/metabolism* ; Cell Line, Tumor

OBJECTIVE: "Multi-targeting" drugs can prove fruitful to combat drug-resistance of multifactorial disease-cervical cancer. This study envisioned to reveal if Thuja homeopathic mother tincture (MT) and its bioactive component could combat human papillomavirus (HPV)-16-infected SiHa cervical cancer cells since it is globally acclaimed for HPV-mediated warts. METHODS: Thuja MT was studied for its antiproliferative and antimigratory properties in SiHa cells followed by microscopic determination of reactive oxygen species (ROS) generation by 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) staining and loss in mitochondrial membrane potential (MtMP) by rhodamine 123 (Rh123) staining. Apoptosis and autophagy inductions were studied by acridine orange/ethidium bromide (AO/EB) staining and immunoblot analyses of marker proteins. The bioactive component of Thuja MT detected by gas chromatography-mass spectrometry was studied for antiproliferative and antimigratory properties along with in silico prediction of its cellular targets by molecular docking and oral drug forming competency. RESULTS: Thuja MT showed significant antiproliferative and antimigratory potential in SiHa cells at a 50% inhibitory concentration (IC₅₀) of 17.3 µL/mL. An increase in DCFDA fluorescence and loss in Rh123 fluorescence prove that Thuja MT acted through the burst of ROS and loss in MtMP respectively. AO/EB-stained cells under the microscope and immunoblot analyses supported Thuja-induced cellular demise via dual pathways-apoptosis and autophagy. Immunoblots showed cleavage of caspase-3 and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) along with upregulation of Beclin-1, microtubule-associated protein 1 light chain 3B (LC3B)-II, and p62 proteins. Hence, the apoptotic cascade followed a caspase-3-dependent pathway supported by PARP-1 cleavage, while autophagic death was Beclin-1-dependent and mediated by accumulation of LC3BII and p62 proteins. Thujone, detected as the bioactive principle of Thuja MT, showed greater anti-proliferative and anti-migratory potential at an IC₅₀ of 77 µg/mL, along with excellent oral drug competency with the ability for gastrointestinal absorption and blood-brain-barrier permeation with nil toxicity. Molecular docking depicted thujone with the strongest affinity for mammalian target of rapamycin, phosphoinositide 3-kinase, and protein kinase B followed by B-cell lymphoma 2, murine double minute 2 and adenosine monophosphate-activated protein kinase, which might act as upstream triggers of apoptotic-autophagic crosstalk. CONCLUSION Robust "multi-targeting" anticancer potential of Thuja drug and thujone for HPV-infected cervical cancer ascertained its therapeutic efficacy for HPV infections.
Animals ; Apoptosis ; Autophagy ; Beclin-1/pharmacology* ; Bicyclic Monoterpenes ; Caspase 3 ; Cell Line, Tumor ; Female ; Humans ; Mammals/metabolism* ; Mice ; Molecular Docking Simulation ; Papillomavirus Infections/drug therapy* ; Phosphatidylinositol 3-Kinases ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Reactive Oxygen Species/metabolism* ; Thuja/metabolism* ; Uterine Cervical Neoplasms/pathology*