mk-1775 and Triple-Negative-Breast-Neoplasms

Adavosertib (AZD1775) is a first-in-class, selective, small-molecule inhibitor of Wee1.. The safety, tolerability, pharmacokinetics, and efficacy of adavosertib monotherapy were evaluated in patients with various solid-tumor types and molecular profiles.. Eligible patients had the following: confirmed diagnosis of ovarian cancer (OC), triple-negative breast cancer (TNBC), or small-cell lung cancer (SCLC); previous treatment for metastatic/recurrent disease; and measurable disease. Patients were grouped into six matched cohorts based on tumor type and presence/absence of biomarkers and received oral adavosertib 175 mg twice a day on days 1-3 and 8-10 of a 21-day treatment cycle.. Eighty patients received treatment in the expansion phase; median total treatment duration was 2.4 months. The most common treatment-related adverse events (AEs) were diarrhea (56.3%), nausea (42.5%), fatigue (36.3%), vomiting (18.8%), and decreased appetite (12.5%). Treatment-related grade ≥ 3 AEs and serious AEs were reported in 32.5% and 10.0% of patients, respectively. AEs led to dose interruptions in 22.5%, reductions in 11.3%, and discontinuations in 16.3% of patients. One patient died following serious AEs of deep vein thrombosis (treatment related) and respiratory failure (not treatment related). Objective response rate, disease control rate, and progression-free survival were as follows: 6.3%, 68.8%, 4.5 months (OC BRCA wild type); 3.3%, 76.7%, 3.9 months (OC BRCA mutation); 0%, 69.2%, 3.1 months (TNBC biomarker [CCNE1/MYC/MYCL1/MYCN] non-amplified [NA]); 0%, 50%, 2 months (TNBC biomarker amplified); 8.3%, 33.3%, 1.3 months (SCLC biomarker NA); and 0%, 33.3%, 1.2 months (SCLC biomarker amplified).. Adavosertib monotherapy was tolerated and demonstrated some antitumor activity in patients with advanced solid tumors.. ClinicalTrials.gov identifier NCT02482311; registered June 2015.

Topics: Female; Humans; Lung Neoplasms; Ovarian Neoplasms; Pyrazoles; Pyrimidinones; Small Cell Lung Carcinoma; Triple Negative Breast Neoplasms

We report results from a phase II study assessing the efficacy of the WEE1 inhibitor adavosertib with cisplatin in metastatic triple-negative breast cancer (mTNBC).. Patients with mTNBC treated with 0-1 prior lines of chemotherapy received cisplatin 75 mg/m. A total of 34 patients initiated protocol therapy; median age was 56 years, 2 patients (6%) had. Among patients with mTNBC treated with 0-1 prior lines, adavosertib combined with cisplatin missed the prespecified ORR cutoff of >30%. The finding of immune-infiltrated tumors in patients with clinical benefit warrants validation.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Cell Cycle Proteins; Chemotherapy, Adjuvant; Cisplatin; Female; Humans; Middle Aged; Progression-Free Survival; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidinones; Triple Negative Breast Neoplasms; Young Adult

Due to its regulation of CDK1/2 phosphorylation, WEE1 plays essentially roles in the regulations of G2/M checkpoint and DNA damage response (DDR). WEE1 inhibition can increase genomic instability by inducing replication stress and G2/M checkpoint inactivation, which result in increased cellular sensitivity to DNA damaging agents. We considered an increase in genomic instability induced by WEE1 inhibition might be used to augment the effects of drugs targeting DNA repair protein. Typically, PARP inhibitors are effective in germline BRCA 1/2 mutated breast and ovarian cancer, but their applicabilities in triple-negative breast cancer (TNBC) are limited. This study was conducted to investigate the anti-tumor effects of the WEE1 inhibitor, AZD1775, and the mechanism responsible for its potentiation of sensitivity to olaparib (a PARP inhibitor) via the modulation of DDR in TNBC cells. Our results suggest that AZD1775 could be used to broaden the application range of olaparib in TNBC and provide a rationale for a clinical trial of combined olaparib and AZD1775 therapy.

Topics: Animals; Apoptosis; Cell Cycle; Cell Cycle Proteins; Cell Proliferation; DNA Damage; DNA Repair; Drug Resistance, Neoplasm; Drug Synergism; Enzyme Inhibitors; Female; Gene Expression Regulation, Neoplastic; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Phthalazines; Piperazines; Poly(ADP-ribose) Polymerase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidinones; Triple Negative Breast Neoplasms; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Triple negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer that poses a clinical challenge. Thus, new therapy strategies are urgently needed. The selective WEE1 inhibitor, AZD1775, has shown strong anti-proliferative effects on a variety of tumors. Here, we first demonstrate that inhibition of ATR by selective inhibitor AZD6738 can enhance AZD1775-caused growth inhibition in TNBC. Our results show that the enhanced cell death is attributed to repressed DNA damage repair and excessive replication stress, thereby causing increased DNA damage reflected by accumulation of the DNA double-strand-break marker γH2AX. On the other hand, combined treatment with AZD6738 and AZD1775 forces mitotic entry of cells with DNA damages by activating CDK1 activity, inducing severely aberrant mitosis and mitotic catastrophe, ultimately resulting in cell death. Dual inhibition of WEE1 and ATR also inactivated RAD51-mediated homologous recombination, which sensitized TNBC cells to cisplatin and PARP inhibitor. Here, based on the preclinical results that ATR inhibition synergizes with WEE1 inhibition in TNBC, we propose that this combination therapy alone, or in parallel with chemotherapy, represents an innovative and potent targeted therapy in TNBC.

Topics: Animals; Antineoplastic Agents; Apoptosis; Ataxia Telangiectasia Mutated Proteins; Cell Cycle Proteins; Cell Death; Cell Line, Tumor; Cell Proliferation; DNA Damage; DNA Repair; Female; Humans; Indoles; MCF-7 Cells; Mice; Mitosis; Morpholines; Nuclear Proteins; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones; Sulfonamides; Sulfoxides; Triple Negative Breast Neoplasms; Xenograft Model Antitumor Assays

Poor prognosis in triple-negative breast cancer (TNBC) is due to an aggressive phenotype and lack of biomarker-driven targeted therapies. Overexpression of cyclin E and phosphorylated-CDK2 are correlated with poor survival in patients with TNBC, and the absence of CDK2 desensitizes cells to inhibition of Wee1 kinase, a key cell-cycle regulator. We hypothesize that cyclin E expression can predict response to therapies, which include the Wee1 kinase inhibitor, AZD1775.. Mono- and combination therapies with AZD1775 were evaluated in TNBC cell lines and multiple patient-derived xenograft (PDX) models with different cyclin E expression profiles. The mechanism(s) of cyclin E-mediated replicative stress were investigated following cyclin E induction or CRISPR/Cas9 knockout by a number of assays in multiple cell lines.. Cyclin E overexpression (i) is enriched in TNBCs with high recurrence rates, (ii) sensitizes TNBC cell lines and PDX models to AZD1775, (iii) leads to CDK2-dependent activation of DNA replication stress pathways, and (iv) increases Wee1 kinase activity. Moreover, treatment of cells with either CDK2 inhibitors or carboplatin leads to transient transcriptional induction of cyclin E (in cyclin E-low tumors) and result in DNA replicative stress. Such drug-mediated cyclin E induction in TNBC cells and PDX models sensitizes them to AZD1775 in a sequential treatment combination strategy.

Topics: Animals; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Cell Cycle Proteins; Cell Line, Tumor; Cyclic N-Oxides; Cyclin E; Disease Models, Animal; DNA Repair; DNA Replication; Drug Resistance, Neoplasm; Gene Expression; Humans; Indolizines; Mice; Mice, Knockout; Models, Biological; Nuclear Proteins; Prognosis; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyridinium Compounds; Pyrimidinones; Stress, Physiological; Triple Negative Breast Neoplasms; Xenograft Model Antitumor Assays