PARP1 overexpression

In vivo experiments exhibited that PPNR-4 showed more effective than the positive controls in inhibiting the growth of tumors. Overall, these data suggest that PPNR-4 is an effective antitumor candidate and deserves further research.

Our work reveals a dual action of DTX3L on TIRR degradation and nuclear exportation and identifies DTX3L as an upstream regulator of the TIRR-53BP1 axis that governs DNA repair pathway choice and PARP inhibitor sensitivity. These findings suggest that TIRR ubiquitination and DTX3L overexpression could be viable biomarkers predicting PARP inhibitor sensitivity in cancers.

We developed paclitaxel-, doxorubicin-, and cisplatin-resistant MDA-MB-231 cells to study MYC's role in upregulating DNA repair genes during drug resistance development...The combined use of asiRNA-VP (Vinylphosphonate) with dacomitinib or talazoparib was synthetic lethal in TNBC cell lines...We confirmed that MYC knockdown upregulated cFLIP, BCL2, STAT1, pSTAT1, STAT2, and cleaved saspase-3 in both TNBC and non-small cell lung cancer (NSCLC) cell lines. Finally, we recommend a combination treatment approach that synergizes with MYC inhibition rather than monotherapy or indirect targeting via upstream regulators such as the BRD4 and RRM2 genes or selective modulation at the protein level to suppress anti-apoptotic genes (cFLIP and BCL2) at the same time.

The study indicates that targeting both HSP90AB1 and PARP1 presents a promising therapeutic strategy for prostate cancer. The synergistic combination of celastrol and olaparib enhances the efficacy of treatment against prostate cancer, offering a potent approach to combat this disease.

Analyses showed that both compounds accomplish Lipinski's Rule of 5, and they both fit into the criteria of good central nervous system (CNS) drugs. Altogether, our data support the idea that QCT and KMF might be plausible candidates for evaluation as therapeutic agents in preclinical models of glioblastoma.

This study discovered a new type of PTM of PARP1 in CC, and showed that PARP1 acetylation at K119 is essential in regulating the proliferation and progression of CC through ERK1/2. Further studies are required to investigate how PARP1 acetylation impact its function.

We previously showed that sensitivity to the PARP7 inhibitor (PARP7i) RBN-2397 could be enhanced by co-treatment with agonists of the Aryl Hydrocarbon Receptor (AHRa) in cell lines that show strong intrinsic sensitivity to RBN-2397...Both wildtype and hormone-resistant mutant forms of these receptors are degraded upon treatment with AHRa and PARP7i in breast and prostate cancer models. These results suggest that combining PARP7i with AHRa may extend the utility of these drugs to a wider range of tumors, including those that are refractory to hormone therapy.

PARP1 may serve as a potential therapeutic target for reversing EGFR-TKI resistance in NSCLC via the PI3K/AKT/mTOR/P70S6K pathway.

Further research showed that PARP-2 inhibited the expression and activity of SIRT1, which in turn was involved in the development of DOX-induced cardiomyocyte aging and injury. Our findings provide a preliminary experimental basis for establishing PARP-2 as a new target for preventing and treating DOX cardiomyopathy and related drug development.

Other cellular events such as Caspase-7 overexpression and PI3K, AKT, PARP, and mTOR inhibition led to the apoptosis in hepatic cancer cells. The mRNA expression profile of PTEN, PI3K, AKT3, caspase-7, PARP and mTOR proteins, primarily controlling the cancer cell proliferation and apoptosis, suggest that exogenous supply of PTEN could regulate the expression of oncogenic proteins and thus cancer progression.

Similar results were obtained by combining Talazoparib and different PARP inhibitors with the alkylating agent cisplatin, indicating a class effect. Importantly, PBMC-derived T cells from healthy donors did not show any sign of DNA damage accumulation upon exposure to Lonca, Talazoparib and the combination. These data provide the rationale for future therapeutic strategies based on selective induction of DNA damage in neoplastic B cells in combination with DDR inhibition in aggressive MYC-positive B cell lymphoma.

This protection may be attributed to the revival of p-Akt signaling for cell survival. It is concluded that the present study demonstrates the neuro-protective effects of friedelin and glutinol via modulating the capase-3 and PARP-1 expression and modulating the neuronal apoptotic pathways.

Notably, PARP1 overexpression reversed the radiosensitizing effect caused by AEG-1 deficiency. Collectively, these findings shed new light on the mechanism of ESCC radioresistance, providing potential therapeutic targets to enhance the efficacy of radiotherapy in ESCC.

Moreover, mitochondrial stress and ROS production induced by sulfatides are rescued by PARP-1 inhibition. Future studies will focus on the signaling cascades triggered by PARP-1-mediated currents in reactive astrocytes and Olaparib as a potential therapeutic target for MLD.

Finally, both USP1 and PARP1 are significantly associated with poor survival in CCA patients. These findings describe PARP1 as a novel deubiquitination target of USP1 and a potential therapeutic target for CCA.

CpG-ODNs may mitigate cervical cancer RKI by blocking the activation of the PARP1/XRCC1 signaling axis, inhibiting DNA damage and oxidative stress response in renal tubule epithelial cells.

Here, a standard frontline drug combination of cytarabine and idarubicin induces distinct features of caspase-independent, poly(ADP-ribose) polymerase 1 (PARP-1)-mediated programmed cell death "parthanatos" in acute myeloid leukemia (AML) cell lines (n = 3/10 tested), peripheral blood mononuclear cells from healthy human donors (n = 10/10 tested), and primary cell samples from patients with AML (n = 18/39 tested, French-American-British subtypes M4 and M5). Manipulation of PARP-1 activity in parthanatos-competent cells reveals higher drug sensitivity in cells that have basal PARP-1 levels as compared with those subjected to PARP-1 overexpression or suppression. The same trends are observed in RNA expression databases and support the conclusion that PARP-1 can have optimal levels for favorable chemotherapeutic responses.

PCC/PGL tumors have high levels of PARP-1 expression. SDHx-associated tumors have previously been shown to be exquisitely sensitive to PARP inhibitors, but in our study had lower levels of PARP-1 and phosphoATM, a marker of DNA damage when compared with tumors without SDHx mutations. These findings suggest that PARP inhibitor susceptibility is independent of SDHx status, and that all PCC/PGL tumors may be susceptible to PARP inhibition.

Furthermore, we found that co-treatment of MCF-7 cells with an inhibitor of AKT (LY294002) or an inhibitor of the proteasome (MG-132) significantly augmented the DRB-induced apoptosis. These data suggested that DRB in combination with LY294002 or MG-132 may have a greater therapeutic potency against breast cancer cells.

The results of this study underscore the significance of BLM overexpression as a prognostic biomarker for PCa, while also demonstrating the negative regulatory impact of PARP1 on BLM transcription. The concurrent targeting of BLM and PARP1 emerges as a promising therapeutic approach for PCa treatment, holding potential clinical significance.

The combination of a WEE1 inhibitor and PARP-1 inhibitor had enhanced efficacy and is proposed as a new therapeutic option for patients with MDS or AML. Our findings have clinical implications for a potential novel therapeutic strategy for MDS and AML patients.

Analysis of RNA sequencing data of HOS cells revealed elevated levels of SH3KBP1 transcript levels in cells resistant to doxorubicin and methotrexate compared to parental cells. Therefore, HOS subclones with Ruk/CIN85 up-regulation were generated, and it was found that these cells are characterized by elevated expression levels of epithelial-mesenchymal transition (EMT) markers vimentin, SNAIL, and SLUG, and decreased E-cadherin content. Also, Ruk/CIN85 overexpression resulted in increased content of PARP and Bcl-XL, indicating resistance to apoptosis.ConclusionThus, elevated expression of adaptor protein Ruk/CIN85 in osteosarcoma cells is associated with resistance to chemotherapeutics and may also influence metastasis propensity.

PARP-1 inhibition by Olaparib or its KO mediates melanoma cell sensitivity to radiotherapy (RT). Similarly, specific inhibition of c-Met by Crizotinib or its KO radiosensitizes the melanoma cell lines...Accordingly, RT associated with the inhibition of both c-Met and PARP-1 resulted in a synergistic effect not only on tumor growth inhibition but also on tumor regrowth control in all animals following the stop of the treatment. We thus show that combining PARP and c-Met inhibition with RT appears a promising therapeutic approach in WTBRAF melanoma.

Candidate genes associated with necroptosis may provide a powerful prognostic tool for precision oncology. Dexmedetomidine may target PARP1 to promote necroptosis and then affect NSCLC.

Prostate cancer cells with TRABID overexpression exhibit a high sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors. Our work shows that TRABID facilitates NHEJ repair over HR during DNA repair by inducing prolonged 53BP1 retention at DSB sites, suggesting that TRABID overexpression may predict HR deficiency and the potential therapeutic use of PARP inhibitors in prostate cancer.

We have not come across any study in the literature to compare PARP expression in BC and BBD patients. On the basis of our observations, we concluded that PARP overexpression is a poor prognostic marker in BC.

By contrast, those features were reduced in mutated p53 cells. These results could implicate that patients with elevated PARP-1 expression and wild type p53 could benefit from PARP-1 inhibition therapies, meanwhile it could have adverse effects for those carrying mutated p53 tumours.

Furthermore, we showed that overexpression of BRCA1 significant increase the olaparib resistance in TRIM47-overexpression-induced PARP inhibitions sensitivity. Taken together, our results uncover a novel mechanism for BRCA1-deficient in TNBC and targeting TRIM47/BRCA1 axis may be a promising prognostic factor and a valuable therapeutic target for TNBC.

Moderate concordance was found with combinations of mASH1 and INSM1 and traditional NE markers, respectively. Consistent overexpression of PARP1 in high-grade tumors with NE differentiation in the HN and lung opens eligibility for PARP1 inhibitor trials.

The elevated DNA damage level in BCAT1 overexpression condition may be therapeutically exploited using therapies that induce or augment DNA damage, such as chemotherapy and PARP inhibitor, Next, we tried to compare the responses of BCAT1 overexpression and control AML cells to the PARP inhibitor BMN673(Talazoparib)...In summary, this study verified BCAT1 high expression is an independent prognostic predictor of CN-AML.BCAT1 reduces intracellular αKG levels, inhibits αKG-dependent histone demethylation enzymes to inhibit H3K9me3 demethylation, thereby suppressing ATM expression and inhibiting DNA damage response in AML cells. Therefore, BCAT1 high expressing AML cells have higher sensitivity to PARP inhibitors.

These results provide critical insights that GA could induce apoptosis in CB3 cells through targeting miR-17-5p by attenuating PARP-1. Thus, GA could act as a novel therapeutic agent for erythroleukemia.

Finally, we identify the CDK2-Cyclin E1 complex as essential for proliferation of PARP10-knockout cells. Our work identifies a network of functionally relevant PARP10 synthetic interactions, and reveals a set of factors which can potentially be targeted in personalized cancer therapy.

To the best of our knowledge we are the first to report that there is a PBX1-SIRT1-PARP1 axis that plays a critical role in alleviating HF-MSCs senescence and apoptosis. We provide a new perspective on the mechanisms underlying stem cell senescence as well as age-related disease prevention and treatment.

We document for the first time that the activation of PARP-1 is an early event during bile reflux-related head and neck carcinogenesis and that NF-κB can mediate DNA damage and PARP-1 activation. Our data encourage further investigation into how acidic bile-induced activated NF-κB mediates DNA damage in hypopharyngeal carcinogenesis.

In 10 μmol/L oxaliplatin treated cells, the apoptosis rate was (6.54±0.68)% in the NAT10 overexpression group and (12.98±2.54)% in the NAT10 knockdown group, both of which were statistically significant (P<0.05) compared with (9.67±0.37)% in wild-type cells. NAT10 overexpression enhances the binding of NAT10 to PARP1 and promotes the acetylation of PARP1, which in turn prolongs the half-life of PARP1, thus enhancing PARP1 recruitment of DNA damage repair related proteins to the damage sites, promoting DNA damage repair and ultimately the survival of breast cancer cells.

Hagiwara, European Urology 2021 2. Motzer, Cancer Cell 2020

All synthesized compounds were more potent than Olaparib (ola) in killing tumor cells, especially in TNBC. Therefore, compound 7 can effectively inhibit TNBC cells with high expression of EGFR. In addition, significant synergistic effect of anti-tumor effect of new PARP inhibitors and adriamycin was also observed.

M7 and M8 were predominantly found in metastatic TNBC patients (p = 0.014 and p = 0.002). Thus, PARP-1 expression and increased mutagenic burden in TNBC patients' CTCs, could be used as an indicator to stratify patients regarding therapeutic approaches.

Autophagy is involved in these processes; miR-126 accumulation induced a protective autophagy and the inhibition of this process by GW4869 generates a metabolic crisis that promotes necroptosis, which was associated with PARP-1 over-expression and cyt-c and AIF release. Here, for the first time, we proposed a therapy against CSCs, a heterogeneous cell population involved in cancer development and relapse.

Idarubicin (IDA), an anthracycline antineoplastic drug, is commonly used in the treatment of acute myeloid leukemia (AML) with reasonable response rates and clinical benefits. Our results suggest that Olaparib attenuates the activity of the NF-κB pathway and decreases the DNA damage response induced by IDA. Therefore, we conclude that Olaparib is a potentially valuable chemosensitizer for leukemia patients.

Therefore, we investigated whether the combination of olaparib and savolitinib, a novel cMET inhibitor, could overcome PARP inhibitor resistance on resistant patient-derived xenografts (PDXs). In this study, cMET inhibition sensitized the resistant tumor to PARP inhibitor. These results indicated that savolitinib, novel cMET inhibitor, could have synergy with the PARP inhibitor for patients with PARP inhibitor resistant ovarian cancer.

Previous data in our lab shows that loss of PARP10 reduces cell proliferation in HeLa cells and its overexpression in RPE-1 cells promotes cellular proliferation. These findings suggest that PARP10 may play a crucial role in cancer biology.