mln-8237 and Neoplasms

Centrosomes are the major microtubule organizing centers in a large number of animal cells. They are involved in diverse cellular functions like cell division, migration, sensing and motility. Despite being identified more than 100 years ago, they did not receive much attention until recent discoveries suggesting their association with human diseases. Centrosome-related defects have been observed in several human diseases including cancers, brain disorders and ciliopathies. Researchers in the field are trying to understand the relationship between centrosomes and these diseases. Accordingly, this review provides an overview of the current knowledge regarding the role of centrosomes during ciliogenesis and neural stem cell division. The review primarily focuses on the impairment of centrosome number, organization and functioning leading to a wide range of human diseases. Finally, we discuss the scope of targeting centrosomes for therapeutic purposes.

Topics: Animals; Antineoplastic Agents; Azepines; Centrosome; Cilia; Ciliopathies; Gene Expression Regulation; Humans; Liver Cirrhosis; Microcephaly; Microtubules; Neoplasms; Nerve Tissue Proteins; Neural Stem Cells; Phthalazines; Pyrimidines; Retinal Degeneration; Signal Transduction

Aurora kinases (AURKs) are serine/threonine protein kinases that play a critical role during cell proliferation. Three isoforms of AURKs reported in mammals include AURKA, AURKB, AURKC, and all share a similar C-terminal catalytic domain with differences in their subcellular location, substrate specificity, and function. Recent research reports indicate an elevated expression of these kinases in several cancer types highlighting their role as oncogenes in tumorigenesis. Inhibition of AURKs is an attractive strategy to design potent inhibitors modulating this target. The last few years have witnessed immense research in the development of AURK inhibitors with few FDA approvals. The current clinical therapeutic regime in cancer is associated with severe side-effects and emerging resistance to existing drugs. This has been the key driver of research initiatives toward designing more potent drugs that can potentially circumvent the emerging resistance. This review is a comprehensive summary of recent research on AURK inhibitors and presents the development of scaffolds, their synthetic schemes, structure-activity relationships, biological activity, and enzyme inhibition potential. We hope to provide the reader with an array of scaffolds that can be selected for further research work and mechanistic studies in the development of new AURK inhibitors.

Topics: Animals; Antineoplastic Agents; Aurora Kinase A; Azepines; Benzamides; Drug Approval; Drug Resistance; Drug Screening Assays, Antitumor; Flavones; Gene Expression Regulation; Humans; Indazoles; Neoplasms; Organophosphates; Protein Binding; Protein Conformation; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Quinazolines; Structure-Activity Relationship

Aurora kinases are essential mediators in cell mitosis. Amplification of these kinases can lead to the development of malignancy and may be associated with inferior survival. Alisertib is an oral aurora kinase inhibitor which has been shown to induce cell-cycle arrest and apoptosis in preclinical studies. It is currently under investigation for a wide variety of malignancies including hematologic (specifically Non-Hodgkin's lymphoma) and solid tumors. Areas covered: A PubMed search was performed to identify clinical studies reporting outcomes with alisertib. Promising results are notable in patients with peripheral T cell lymphoma in particular, forming the basis for the first phase 3 randomized trial of alisertib. Although it did show encouraging response rates, it failed to demonstrate superiority over the comparator arm at an interim analysis, halting further enrollment. Expert opinion: Despite disappointing early results, alisertib remains under investigation in a number of cancer types both as monotherapy and in combination with traditional cytotoxic chemotherapy, with encouraging results. Most common toxicities in early trials include myelosuppression alopecia, mucositis and fatigue. The relatively manageable toxicity profile of alisertib along with ease of dosing may allow it to be combined with other oral agents or traditional chemotherapy across a wide variety of malignancy types.

Topics: Animals; Antineoplastic Agents; Apoptosis; Aurora Kinase A; Azepines; Humans; Lymphoma, Non-Hodgkin; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Randomized Controlled Trials as Topic

The Myc proteins comprise a family of ubiquitous regulators of gene expression implicated in over half of all human cancers. They interact with a large number of other proteins, such as transcription factors, chromatin-modifying enzymes and kinases. Remarkably, few of these interactions have been characterized structurally. This is at least in part due to the intrinsically disordered nature of Myc proteins, which adopt a defined conformation only in the presence of binding partners. Owing to this behaviour, crystallographic studies on Myc proteins have been limited to short fragments in complex with other proteins. Most recently, we determined the crystal structure of Aurora-A kinase domain bound to a 28-amino acid fragment of the N-Myc transactivation domain. The structure reveals an α-helical segment within N-Myc capped by two tryptophan residues that recognize the surface of Aurora-A. The kinase domain acts as a molecular scaffold, independently of its catalytic activity, upon which this region of N-Myc becomes ordered. The binding site for N-Myc on Aurora-A is disrupted by certain ATP-competitive inhibitors, such as MLN8237 (alisertib) and CD532, and explains how these kinase inhibitors are able to disrupt the protein-protein interaction to affect Myc destabilization. Structural studies on this and other Myc complexes will lead to the design of protein-protein interaction inhibitors as chemical tools to dissect the complex pathways of Myc regulation and function, which may be developed into Myc inhibitors for the treatment of cancer.

Topics: Aurora Kinase A; Azepines; Humans; Neoplasms; Phenylurea Compounds; Protein Binding; Protein Interaction Domains and Motifs; Protein Kinase Inhibitors; Protein Structure, Tertiary; Proto-Oncogene Proteins c-myc; Pyrimidines

Many current anticancer chemotherapeutics suffer from significant side effects, which have led to the exploration of more targeted therapies. This resulted in the exploration of inhibitors of Aurora A kinase as a potential anti-cancer treatment. Alisertib (MLN8237) has proven to be a potent Aurora A kinase inhibitor that had the highest safety profile among its therapeutic family. Phase I/II/III clinical trials with Alisertib have been carried out and reported promising efficacy, yet serious side effects. This article attempts to assess the clinical effect of Alisertib administration in various cancer phenotypes while describing the reported side effects.. Alisertib clinical data were systematically retrieved from Medline, CINAHL, PubMed, and Cochrane Central Register of Controlled Trials and analyzed for quality, relevance, and originality in three stages prior to inclusion.. Overall, seven studies met inclusion criteria and enrolled a total of 630 patients. The reported "potential" clinical effect of Alisertib in various tumours is promising as it improved time to disease progression, progression-free survival, and the duration of disease stability. The achieved improvement therefore rationalizes its further investigation as a novel anticancer therapy. However, the administration of the drug was associated with serious haematological disturbances in a relatively high percentage of patients.. The evidence of the anti-tumour effect of Alisertib administration is compelling in various types of malignancies. The reported side effects were serious but manageable in many cases. Topical or more targeted routes of administration are suggested when possible to overcome off-target events with systematic administration of the drug.

Topics: Aurora Kinase A; Azepines; Humans; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Risk Assessment

Topics: Animals; Antineoplastic Agents; Aurora Kinases; Drug Discovery; Humans; Mitosis; Neoplasms; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases

Aurora Kinase A (AKA) inhibition with gemcitabine represents a potentially synergistic cancer treatment strategy via mitotic catastrophe. The feasibility, safety, and preliminary efficacy of alisertib (MLN8237), an oral AKA inhibitor, with gemcitabine was evaluated in this open-label phase I trial with dose escalation and expansion.. Key inclusion criteria included advanced solid tumor with any number of prior chemotherapy regimens in the dose escalation phase, and advanced pancreatic adenocarcinoma with up to two prior chemotherapy regimens. Four dose levels (DLs 1-4) of alisertib (20, 30, 40, or 50 mg) were evaluated in 3 + 3 design with gemcitabine 1000 mg/m. In total, 21 subjects were treated in dose escalation and 5 subjects were treated in dose expansion at DL4. Dose-limiting toxicities were observed in 1 of 6 subjects each in DL3 and DL4. All subjects experienced treatment-related adverse events. Grade ≥ 3 treatment-related adverse events were observed in 73% of subjects, with neutropenia observed in 54%. Out of 22 subjects evaluable for response, 2 subjects (9%) had partial response and 14 subjects (64%) had stable disease. Median PFS was 4.1 months (95% CI 2.1-4.5). No significant changes in pharmacokinetic parameters for gemcitabine or its metabolite dFdU were observed with alisertib co-administration.. This trial established the recommended phase 2 dose of alisertib 50 mg to be combined with gemcitabine. Gemcitabine and alisertib are a feasible strategy with potential for disease control in multiple heavily pre-treated tumors, though gastrointestinal and hematologic toxicity was apparent.

Topics: Adenocarcinoma; Antineoplastic Combined Chemotherapy Protocols; Azepines; Deoxycytidine; Gemcitabine; Humans; Maximum Tolerated Dose; Neoplasms; Pancreatic Neoplasms; Pyrimidines

Aurora kinases are overexpressed or amplified in numerous malignancies. This study was designed to determine the safety and tolerability of the Aurora A kinase inhibitor alisertib (MLN8237) when combined with weekly irinotecan.. In this single-center phase 1 study, adult patients with refractory advanced solid tumors received 100 mg/m. A total of 17 patients enrolled at three dose levels. Dose-limiting toxicities included diarrhea, dehydration, and neutropenia. The MTD of alisertib combined with weekly irinotecan was 20 mg twice per day on days 1-3 and 8-10. One fatal cardiac arrest at the highest dose level tested was deemed possibly related to drug treatment. One partial response in 11 efficacy evaluable patients (9%) occurred in a patient with small cell lung cancer. The study was terminated prior to the planned expansion in patients with colorectal cancer.. In contrast to prior results in a pediatric population, adult patients did not tolerate alisertib combined with irinotecan at clinically meaningful doses due to hematologic and gastrointestinal toxicities. The study was registered with ClinicalTrials.gov under study number NCT01923337 on Aug 15, 2013.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Azepines; Cohort Studies; Drug Administration Schedule; Female; Humans; Irinotecan; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Young Adult

The purpose of this study was to evaluate the rational combination of TORC1/2 inhibitor TAK-228 and Aurora A kinase inhibitor alisertib in preclinical models of triple-negative breast cancer (TNBC) and to conduct a phase I dose escalation trial in patients with advanced solid tumors.. TNBC cell lines and patient-derived xenograft (PDX) models were treated with alisertib, TAK-228, or the combination and evaluated for changes in proliferation, cell cycle, mTOR pathway modulation, and terminal cellular fate, including apoptosis and senescence. A phase I clinical trial was conducted in patients with advanced solid tumors treated with escalating doses of alisertib and TAK-228 using a 3+3 design to determine the maximum tolerated dose (MTD).. The combination of TAK-228 and alisertib resulted in decreased proliferation and cell-cycle arrest in TNBC cell lines. Treatment of TNBC PDX models resulted in significant tumor growth inhibition and increased apoptosis with the combination. In the phase I dose escalation study, 18 patients with refractory solid tumors were enrolled. The MTD was alisertib 30 mg b.i.d. days 1 to 7 of a 21-day cycle and TAK-228 2 mg daily, continuous dosing. The most common treatment-related adverse events were neutropenia, fatigue, nausea, rash, mucositis, and alopecia.. The addition of TAK-228 to alisertib potentiates the antitumor activity of alisertib

Topics: Aged; Animals; Antineoplastic Combined Chemotherapy Protocols; Aurora Kinase A; Azepines; Benzoxazoles; Cell Line, Tumor; Drug Resistance, Neoplasm; Female; Humans; Male; Maximum Tolerated Dose; Mechanistic Target of Rapamycin Complex 1; Mechanistic Target of Rapamycin Complex 2; Mice; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Xenograft Model Antitumor Assays

Aurora A kinase (AAK) plays an integral role in mitotic entry, DNA damage checkpoint recovery, and centrosome and spindle maturation. Alisertib (MLN8237) is a potent and selective AAK inhibitor. In pediatric preclinical models, antitumor activity was observed in neuroblastoma, acute lymphoblastic leukemia, and sarcoma xenografts. We conducted a phase 2 trial of alisertib in pediatric patients with refractory or recurrent solid tumors or acute leukemias (NCT01154816).. A total of 139 children and adolescents (median age, 10 years) were enrolled, 137 were evaluable for response. Five objective responses were observed (2 complete responses and 3 partial responses). The most frequent toxicity was myelosuppression. The median alisertib trough concentration on day 4 was 1.3 μmol/L, exceeding the 1 μmol/L target trough concentration in 67% of patients. No correlations between PG or PK and toxicity were observed.. Despite alisertib activity in pediatric xenograft models and cogent pharmacokinetic-pharmacodynamic relationships in preclinical models and adults, the objective response rate in children and adolescents receiving single-agent alisertib was less than 5%.

Topics: Adolescent; Animals; Antineoplastic Agents; Azepines; Biomarkers, Tumor; Child; Child, Preschool; Disease Models, Animal; Drug Resistance, Neoplasm; Female; Humans; Leukemia; Male; Mice; Multimodal Imaging; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Recurrence; Retreatment; Treatment Outcome; Xenograft Model Antitumor Assays; Young Adult

Pazopanib is a multikinase angiogenesis inhibitor. Alisertib is a highly selective inhibitor of mitotic Aurora A kinase. There is preclinical evidence that mitosis-targeting agents exhibit antiangiogenic effects. Thus, the combination of these 2 agents may have a synergistic effect on tumor vasculature. The primary objective of this study is to determine the optimal tolerated dose (OTD) for alisertib and pazopanib.. This phase 1b study evaluated the OTD of alisertib twice a day, on days 1 to 7 with pazopanib, once a day, continuously in a 21-day cycle, both taken orally. Disease response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.1 every 2 cycles. OTD cohort was expanded to assure safety and perform pharmacokinetics analysis.. A total of 27 patients received treatment. Seventy-seven percent of the patients had received at least 3 prior chemotherapy regimens. Dose-limiting toxicities occurred in dose level (DL) 2+ (grade 4 thrombocytopenia and grade 3 mucositis) and DL 3 (grade 3 liver transaminases elevation and grade 3 abdominal pain). The OTD was determined to be DL 2: alisertib 20 mg twice daily and pazopanib 600 mg daily. Pharmacokinetic analysis revealed that clearance of alisertib was reduced by ∼40% in the presence of pazopanib compared with clearance in the absence of pazopanib. Fourteen patients had stable disease and 2 patients had a partial response.. The combination of alisertib with pazopanib demonstrates manageable safety and early clinical evidence of antitumor activity in patients with advanced malignancies (NCT01639911).

Topics: Adult; Age Factors; Aged; Azepines; Cohort Studies; Disease-Free Survival; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Therapy, Combination; Female; Humans; Indazoles; Kaplan-Meier Estimate; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Invasiveness; Neoplasm Staging; Neoplasms; Patient Safety; Pyrimidines; Response Evaluation Criteria in Solid Tumors; Retrospective Studies; Risk Assessment; Sex Factors; Sulfonamides; Survival Analysis; Treatment Outcome

This clinical trial was designed to evaluate the effect of moderate or severe hepatic impairment on the single-dose pharmacokinetics (PK) of the investigational anticancer agent, alisertib, in adult patients with advanced solid tumors or lymphoma. Patients with normal hepatic function (total bilirubin and alanine transaminase [ALT] ≤ upper limit of normal [ULN]), moderate hepatic impairment (1.5 × ULN < total bilirubin ≤ 3 × ULN, with any ALT) or severe hepatic impairment (total bilirubin > 3 × ULN, with any ALT), received a single 50-mg oral dose of alisertib. Blood samples for PK were collected up to 168 hours postdose. Predose samples were also used to assess alisertib plasma protein binding. Patients could continue to receive alisertib for 7 days in 21-day cycles (50, 30, or 10 mg twice daily for normal hepatic function, moderate hepatic impairment, and severe hepatic impairment, respectively). Alisertib was approximately 99% protein bound in all hepatic function groups. Alisertib exposure was similar in moderate and severe hepatic impairment groups, but higher than the normal hepatic function group. The geometric least-squares mean ratios (90% confidence intervals) for unbound alisertib area under the curve extrapolated to infinity for moderate/severe impairment groups versus the normal hepatic function group was 254% (184%, 353%). Patients with moderate or severe hepatic impairment have approximately 150% higher unbound alisertib exposures compared with patients with normal hepatic function. An approximately 60% reduction of the starting dose of alisertib in patients with moderate/severe hepatic impairment is recommended based on pharmacokinetic considerations.

Topics: Adult; Aged; Antineoplastic Agents; Area Under Curve; Aurora Kinase A; Azepines; Drugs, Investigational; Female; Humans; Liver Diseases; Lymphoma; Male; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines

Aims A primary objective of this study was to investigate the effect of single and multiple doses of alisertib, an investigational Aurora A kinase inhibitor, on the QTc interval in patients with advanced malignancies. The dose regimen used was the maximum tolerated dose which was also the recommended phase 3 dose (50 mg twice daily [BID] for 7 days in 21-day cycles). Methods Patients received a single dose of alisertib (50 mg) on Day 1, and multiple doses of alisertib (50 mg BID) on Days 4 through to the morning of Day 10 of the first cycle of treatment. Triplicate ECGs were collected at intervals over 10 to 24 h via Holter recorders on Days -1 (baseline), 1 and 10. Changes from time-matched baseline values were calculated for various ECG parameters including QTc, heart rate, PR and QRS intervals. Alisertib pharmacokinetics were also assessed during the study, and an exposure-QTc analysis was conducted. Results Fifty patients were included in the QTc analysis. The upper bounds of the 95% confidence intervals for changes from time-matched baseline QTcF and QTcI values were <5 ms across all study days, time points and correction methods. Alisertib did not produce clinically relevant effects on heart rate, PR or QRS intervals. There was no evidence of a concentration-QTc effect relationship. Conclusions Alisertib does not cause QTc prolongation and can be concluded to not have any clinically relevant effects on cardiac repolarization or ECG parameters at the single agent maximum tolerated dose of 50 mg BID.

Topics: Aurora Kinase A; Azepines; Drugs, Investigational; Electrocardiography; Female; Heart Rate; Humans; Male; Metabolome; Neoplasms; Protein Kinase Inhibitors; Pyrimidines

Alisertib (MLN8237) is an investigational, oral, selective Aurora A kinase inhibitor. Aurora A contains two functional single nucleotide polymorphisms (SNPs; codon 31 [F/I] and codon 57 [V/I]) that lead to functional changes. This study investigated the prognostic and predictive significance of these SNPs.. This study evaluated associations between Aurora A SNPs and overall survival (OS) in The Cancer Genome Atlas (TCGA) database. The Aurora A SNPs were also evaluated as predictive biomarkers for clinical outcomes to alisertib in two phase 2 studies (NCT01045421 and NCT01091428). Aurora A SNP genotyping was obtained from 85 patients with advanced solid tumors receiving single-agent alisertib and 122 patients with advanced recurrent ovarian cancer treated with alisertib plus weekly paclitaxel (n=62) or paclitaxel alone (n=60). Whole blood was collected prior to treatment and genotypes were analyzed by PCR.. TCGA data suggested prognostic significance for codon 57 SNP; solid tumor patients with VV and VI alleles had significantly reduced OS versus those with II alleles (HR 1.9 [VI] and 1.8 [VV]; p<0.0001). In NCT01045421, patients carrying the VV alleles at codon 57 (n=53, 62%) had significantly longer progression-free survival (PFS) than patients carrying IV or II alleles (n=32, 38%; HR 0.5; p=0.0195). In NCT01091428, patients with the VV alleles at codon 57 who received alisertib plus paclitaxel (n=47, 39%) had a trend towards improved PFS (7.5months) vs paclitaxel alone (n=32, 26%; 3.8months; HR 0.618; p=0.0593). In the paclitaxel alone arm, patients with the VV alleles had reduced PFS vs modified intent-to-treat (mITT) patients (3.8 vs 5.1months), consistent with the TCGA study identifying the VV alleles as a poor prognostic biomarker. No significant associations were identified for codon 31 SNP from the same data set.. These findings suggest that Aurora A SNP at codon 57 may predict disease outcome and response to alisertib in patients with solid tumors. Further investigation is warranted.

Topics: Adult; Aged; Alleles; Aurora Kinase A; Azepines; Biomarkers, Tumor; Disease-Free Survival; Female; Humans; Male; Middle Aged; Neoplasm Staging; Neoplasms; Paclitaxel; Polymorphism, Single Nucleotide; Protein Kinase Inhibitors; Pyrimidines; Treatment Outcome

This study was conducted to characterize the effects of food on single-dose pharmacokinetics (PK) of the investigational Aurora A kinase inhibitor alisertib (MLN8237) in patients with advanced solid tumors.. Following overnight fasting for 10 h, a single 50 mg enteric-coated tablet (ECT) of alisertib was administered under either fasted (alisertib with 240 mL of water) or fed (high-fat meal consumed 30 min before receiving alisertib with 240 mL of water) conditions using a two-cycle, two-way crossover design. Patients on both arms were not allowed food for 4 h post-dose. Water was allowed as desired, except for 1 h before and after alisertib administration.. Twenty-four patients were enrolled and 14 patients were PK-evaluable (ten patients were not PK-evaluable due to insufficient data). Following a single oral dose of alisertib, median t max was 6 h and 3 h under fed and fasted conditions, respectively. The geometric mean ratio of AUCinf (fed- vs. fasted-state dosing) was 0.94 [90% confidence interval (CI) 0.68-1.32]. The geometric mean C max under fed conditions was 84% of that under fasted conditions (90% CI 66-106). Alisertib was generally well-tolerated; most common drug-related grade 3/4 adverse events included neutropenia (50%), leukopenia (38%), and thrombocytopenia (21%).. Systemic exposures achieved following a single 50 mg dose of alisertib administered as an ECT formulation after a high-fat meal are similar to those observed in the fasted state. Alisertib 50 mg ECT can be administered without regard for food. CLINICALTRIALS.. NCT00962091.

Topics: Adult; Aged; Antineoplastic Agents; Aurora Kinase A; Azepines; Cross-Over Studies; Dose-Response Relationship, Drug; Female; Food-Drug Interactions; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines

This study was designed to determine the safety, tolerability, and pharmacokinetics (PK) of alisertib (MLN8237) in combination with docetaxel and to identify a recommended dose for the combination.. Adults with metastatic cancer were treated on 21-day cycles with alisertib (10, 20, 30, or 40 mg) twice daily on days 1 to 7 or days 1 to 5 and with docetaxel (75 or 60 mg/m(2) ) on day 1. The primary objectives were to assess the safety and tolerability of the combination and to determine the recommended phase 2 dose (RP2D) for future studies. Secondary objectives included an efficacy assessment and PK analyses of docetaxel and alisertib.. Forty-one patients participated. Eight dose levels were explored with various doses of alisertib and docetaxel. The dose-limiting toxicities were neutropenic fever, neutropenia without fever, stomatitis, and urinary tract infection. The RP2D of this combination was 20 mg of alisertib twice daily on days 1 to 7 and intravenous docetaxel at 75 mg/m(2) on day 1 in 21-day cycles. Eight of the 28 patients (29%) who were efficacy-evaluable had objective responses. These included 1 complete response in a patient with bladder cancer, 6 partial responses in patients with castration-resistant prostate cancer, and 1 partial response in a patient with angiosarcoma. Concomitant administration of alisertib did not produce any clinically meaningful change in docetaxel PK.. Alisertib at 20 mg twice daily on days 1 to 7 with intravenous docetaxel at 75 mg/m(2) on day 1 in a 21-day cycle was well tolerated, and the combination demonstrated antitumor activity. Cancer 2016;122:2524-33. © 2016 American Cancer Society.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Aurora Kinase A; Azepines; Biomarkers; Docetaxel; Drug Administration Schedule; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Grading; Neoplasm Staging; Neoplasms; Pyrimidines; Taxoids; Treatment Outcome

Alisertib (MLN8237) is an investigational, oral, small-molecule, selective inhibitor of Aurora A kinase. Phase I/II studies of powder-in-capsule (PIC) and enteric-coated tablet formulations of alisertib have determined the recommended phase II dose and have demonstrated anti-tumor activity. This phase I relative bioavailability study characterized the pharmacokinetics of a prototype oral solution (OS) of alisertib (developed for patients unable to swallow solid dosage forms) in reference to the PIC formulation in adult cancer patients.. A safety evaluation was undertaken first following a 3+3 design (OS starting dose, 15 mg). The relative bioavailability of alisertib OS vs. PIC was then evaluated following single dose administration of alisertib OS 25 mg and PIC 50 mg, using a 2-way crossover study design.. The relative bioavailability (geometric mean dose-normalized AUCinf ratio) of alisertib OS vs. PIC formulation was 1.26 (90% confidence interval (CI): 1.09-1.47 (OS, n=17; PIC, n=18 evaluable patients)). These results support a distinguishable difference in bioavailability of alisertib between the two formulations (lower bound of 90% CI>1), with an estimated 26% higher total systemic exposure with alisertib OS vs. PIC. Alisertib absorption from OS was faster than from PIC, with a shorter median tmax (OS, 1 hour; PIC, 2 hours) and a geometric mean dose-normalized Cmax ratio (OS vs. PIC) of 1.90 (90% CI: 1.52 - 2.37).. These findings inform the starting dose of alisertib OS to support further clinical evaluation of alisertib in patients unable to swallow solid dosage forms.

Topics: Administration, Oral; Adult; Aged; Antineoplastic Agents; Area Under Curve; Aurora Kinase A; Azepines; Biological Availability; Capsules; Chemistry, Pharmaceutical; Cross-Over Studies; Female; Gastrointestinal Absorption; Humans; Male; Middle Aged; Neoplasms; Pharmaceutical Solutions; Powders; Protein Kinase Inhibitors; Pyrimidines; Treatment Outcome; United States; Young Adult

This phase 1 study assessed the pharmacokinetics (PK), maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), safety, and preliminary efficacy of the investigational Aurora A kinase inhibitor, alisertib, in East Asian patients with advanced solid tumors or lymphomas.. Patients received alisertib twice-daily (BID) for 7 days in 21-day cycles. Doses were escalated (3 + 3) from 30 mg BID based on cycle 1 dose-limiting toxicities (DLTs) until the MTD, followed by expansion for PK/safety characterization.. Thirty-six patients (61 % Chinese, 36 % Korean, 3 % Malay) received alisertib (30 mg BID, n = 30; 40 mg BID, n = 6; median, 2.5 cycles). Alisertib exposures increased approximately dose proportionally, and mean half-life was 16 h. Geometric mean apparent oral clearance (2.65 L/h) was 40 % lower than previous estimates in Western patients, resulting in approximately 70 % higher mean dose-normalized, steady-state exposures (735 nM*h/mg) in East Asian patients. Two patients experienced DLTs at 40 mg BID (grade 3 stomatitis; grade 4 neutropenia); the MTD/RP2D was 30 mg BID. Common toxicities (grade ≥3 at RP2D) were neutropenia (50 %), diarrhea (13 %), and stomatitis (10 %). One patient with extranodal T-/NK-cell lymphoma (nasal type) achieved a partial response and 18 (51 %) had stable disease.. The MTD/RP2D of alisertib in East Asian patients (30 mg BID) was lower than in Western patients (50 mg BID), consistent with higher systemic exposures in the East Asian population. Alisertib was generally well tolerated and showed signs of antitumor activity in East Asian cancer patients.

Topics: Adult; Aged; Antineoplastic Agents; Asian People; Aurora Kinase A; Azepines; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Treatment Outcome; Young Adult

This phase 1b study evaluated an enteric-coated tablet (ECT) formulation of the investigational Aurora A kinase inhibitor, alisertib (MLN8237).. Patients with advanced, non-hematologic malignancies received oral alisertib ECT for 7 d BID followed by 14 d treatment-free (21-day cycles; 3 + 3 dose escalation schema). Objectives were to assess safety, pharmacokinetics, and antitumor activity, and to define a recommended phase 2 dose (RP2D) of alisertib.. 24 patients were treated. Median age was 57 years. Patients received a median of 2 cycles (range 1-12). The RP2D was determined as 50 mg BID for 7 d (21-day cycles). A cycle 1 dose-limiting toxicity of grade 4 febrile neutropenia was observed in 1 of 13 patients at RP2D. The most common drug-related adverse event (AE) was neutropenia (50%). At doses ≥ 40 mg BID, 7 patients had drug-related AEs that were serious but largely reversible/manageable by dose reduction and supportive care, including 3 with febrile neutropenia. Pharmacokinetic data were available in 24 patients. Following administration of alisertib ECT, the plasma peak concentration of alisertib was achieved at ~3 h; systemic exposure increased with increasing dose over 10-60 mg BID. Mean t½ was ~21 h following multiple dosing. Renal clearance was negligible. Nine patients achieved stable disease (3.98*, 5.59, 1.28*, 2.56, 5.45*, 3.48, 3.15, 8.31, and 6.93* months; *censored).. Alisertib ECT was generally well tolerated in adults with advanced, non-hematologic malignancies. The RP2D is 50 mg BID for 7 d and is being evaluated in ongoing phase 2 studies.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Aurora Kinase A; Azepines; Dose-Response Relationship, Drug; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines; Response Evaluation Criteria in Solid Tumors; Tablets

Aurora A kinase (AAK) is a key regulator of mitosis and a target for anticancer drug development. This phase I study investigated the safety, pharmacokinetics, and pharmacodynamics of MLN8237 (alisertib), an investigational, oral, selective AAK inhibitor, in 59 adults with advanced solid tumors.. Patients received MLN8237 once daily or twice daily for 7, 14, or 21 consecutive days, followed by 14 days recovery, in 21-, 28-, or 35-day cycles. Dose-limiting toxicities (DLT) and the maximum-tolerated dose (MTD) for the 7- and 21-day schedules were determined. Pharmacokinetic parameters were derived from plasma concentration-time profiles. AAK inhibition in skin and tumor biopsies was evaluated and antitumor activity assessed.. Neutropenia and stomatitis were the most common DLTs. The MTD for the 7- and 21-day schedules was 50 mg twice daily and 50 mg once daily, respectively. MLN8237 absorption was fast (median time to maximum concentration, 2 hours). Mean terminal half-life was approximately 19 hours. At steady state, pharmacodynamic effects were shown by accumulation of mitotic and apoptotic cells in skin, and exposure-related increases in numbers of mitotic cells with characteristic spindle and chromosomal abnormalities in tumor specimens, supporting AAK inhibition by MLN8237. Stable disease was observed and was durable with repeat treatment cycles, administered over 6 months, in 6 patients, without notable cumulative toxicity.. The recommended phase II dose of MLN8237 is 50 mg twice daily on the 7-day schedule, which is being evaluated further in a variety of malignancies, including in a phase III trial in peripheral T-cell lymphoma.

Topics: Adult; Aged; Antineoplastic Agents; Aurora Kinases; Azepines; Biopsy; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Staging; Neoplasms; Neutropenia; Protein Serine-Threonine Kinases; Pyrimidines; Stomatitis

This phase I study evaluated the safety, pharmacokinetics, pharmacodynamics, and efficacy of the investigational oral drug MLN8237 (alisertib), a small-molecule Aurora A kinase (AAK) inhibitor, in 87 adult patients with advanced solid tumors.. Sequential cohorts of patients received MLN8237 5 to 150 mg orally once daily or twice daily for 7, 14, or 21 days, followed by 14 days' rest per cycle. MLN8237 pharmacokinetics was characterized, and the relative bioavailability of an enteric-coated tablet (ECT) formulation was evaluated in reference to the original powder-in-capsule (PIC) formulation. Pharmacodynamic effects of MLN8237 on inhibition of AAK activity were evaluated in skin biopsies. Tolerability and response to treatment were assessed.. Common toxicities included fatigue, nausea, and neutropenia. Plasma exposures increased dose proportionally (5-150 mg/d), and were similar for PIC and ECT. The terminal half-life was 23 hours. At the maximum tolerated dose of 50 mg twice daily on the 7-day schedule, the mitotic index of the skin basal epithelium was increased within 24 hours after MLN8237 administration on days 1 and 7, a finding consistent with AAK inhibition. One (1%) patient achieved a partial response lasting for more than 1 year and received MLN8237 for 51 cycles; 20 (23%) patients achieved stable disease for ≥3 months.. This first-in-human trial of MLN8237 showed tolerability and favorable pharmacokinetics in this patient population. The recommended phase II dose of MLN8237 is 50 mg twice daily orally for 7 days in 21-day cycles, which is being evaluated further in the treatment of various solid tumors and hematologic malignancies.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Aurora Kinases; Azepines; Biological Availability; Biopsy; Dose-Response Relationship, Drug; Fatigue; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Nausea; Neoplasm Staging; Neoplasms; Neutropenia; Protein Serine-Threonine Kinases; Pyrimidines

MLN8237, a selective small-molecule inhibitor of Aurora kinase A, has activity in a broad range of preclinical pediatric cancer models. We conducted a phase I trial in children with refractory/recurrent solid tumors to define the maximum-tolerated dose, toxicities, and pharmacokinetic properties of MLN8237.. MLN8237 was administered orally either once daily or divided twice daily for seven days, every 21 days. Using a rolling-six design, four dose levels (45, 60, 80, and 100 mg/m(2)/day) were evaluated on the once-daily schedule, and two dose levels (60 and 80 mg/m(2)/d) on the twice-daily schedule. Pharmacokinetic studies were conducted with the initial dose and trough drug concentrations also measured at the steady state.. Thirty-seven patients were enrolled. On the once-daily dosing schedule, myelosuppression was dose limiting in three of four patients at 100 mg/m(2), and one of six patients had dose-limiting mood alteration at 80 mg/m(2). At 45 mg/m(2), one of six patients experienced dose-limiting mucositis. Mucositis and myelosuppression were dose limiting at 80 mg/m(2) on the twice-daily schedule, and one of five patients at 60 mg/m(2) on the twice-daily schedule experienced a dose-limiting alkaline phosphatase. Five of 11 patients experienced hand-foot-skin syndrome with twice-daily dosing versus one of 21 after once-daily dosing. There was one partial response and six with prolonged stable disease among 33 evaluable subjects.. The twice-daily dose regimen is well tolerated in adults; however, children experienced a greater frequency of myelosuppression and hand-foot-skin syndrome on this schedule. Children tolerated a higher dose and the recommended pediatric phase II dose is 80 mg/m(2)/d once daily for seven days.

Topics: Adolescent; Antineoplastic Agents; Azepines; Child; Child, Preschool; Female; Humans; Male; Neoplasms; Pyrimidines; Treatment Outcome; Young Adult

Cellular senescence is characterized as a stable proliferation arrest that can be triggered by multiple stresses. Most knowledge about senescent cells is obtained from studies in primary cells. However, senescence features may be different in cancer cells, since the pathways that are involved in senescence induction are often deregulated in cancer. We report here a comprehensive analysis of the transcriptome and senolytic responses in a panel of 13 cancer cell lines rendered senescent by two distinct compounds. We show that in cancer cells, the response to senolytic agents and the composition of the senescence-associated secretory phenotype are more influenced by the cell of origin than by the senescence trigger. Using machine learning, we establish the SENCAN gene expression classifier for the detection of senescence in cancer cell samples. The expression profiles and senescence classifier are available as an interactive online Cancer SENESCopedia.

Topics: Aniline Compounds; Azepines; Cell Line, Tumor; Cellular Senescence; Etoposide; Gene Expression Regulation, Neoplastic; Humans; Neoplasms; Pyrimidines; Reproducibility of Results; Senescence-Associated Secretory Phenotype; Senotherapeutics; Sulfonamides

Alisertib (MLN8237) is an investigational, orally available, selective aurora A kinase inhibitor in clinical development for the treatment of solid tumors and hematologic malignancies. This metabolic profiling analysis was conducted as part of a broader phase 1 study evaluating mass balance, pharmacokinetics, metabolism, and routes of excretion of alisertib following a single 35-mg dose of [

Topics: Administration, Oral; Aged; Antineoplastic Agents; Aurora Kinase A; Azepines; Biotransformation; Cytochrome P-450 CYP3A; Feces; Female; Glucuronides; Humans; Male; Middle Aged; Neoplasms; Protein Kinase Inhibitors; Pyrimidines

Overexpressed Aurora-A kinase promotes tumor growth through various pathways, but whether Aurora-A is also involved in metabolic reprogramming-mediated cancer progression remains unknown. Here, we report that Aurora-A directly interacts with and phosphorylates lactate dehydrogenase B (LDHB), a subunit of the tetrameric enzyme LDH that catalyzes the interconversion between pyruvate and lactate. Aurora-A-mediated phosphorylation of LDHB serine 162 significantly increases its activity in reducing pyruvate to lactate, which efficiently promotes NAD

Topics: Animals; Aurora Kinase A; Azepines; Cell Line, Tumor; Glycolysis; HEK293 Cells; HeLa Cells; Humans; Isoenzymes; L-Lactate Dehydrogenase; Lactic Acid; Male; Mice, Inbred BALB C; Mice, Nude; Mutation; Neoplasms; Phosphorylation; Pyrimidines; Pyruvic Acid; Serine; Substrate Specificity; Tumor Burden; Xenograft Model Antitumor Assays

This population pharmacokinetic analysis was conducted to describe quantitatively the regional differences and sources of interpatient variability on the apparent oral clearance of alisertib.. A population pharmacokinetic analysis was performed on data from 671 cancer patients in Western countries and in Japan/East Asia to whom alisertib 5-150 mg once or twice daily (b.i.d.) was administered in multiple dosing schedules. The final model was used to simulate alisertib pharmacokinetics in patients in the West and East Asian regions in the single-agent schedule of 7 days of dosing in a 21-day cycle. Exposure-safety relationships for mechanism-related antiproliferative toxicities (neutropenia, mucositis and diarrhoea) were estimated by logistic regression.. Alisertib pharmacokinetics were described by a two-compartment model with four-transit compartment absorption and linear elimination. The final model included a covariate effect of region on relative bioavailability, with patients in the East Asian region estimated to have a 52% higher bioavailability compared with Western patients. Population simulated exposure at 30 mg b.i.d. in patients in Asia was similar to that at 50 mg b.i.d. in Western patients [geometric mean (coefficient of variation) steady state area under the concentration-time curve over the dosing interval (AUC. Model-based simulations support the achievement of similar alisertib exposures in patients in Asia who are administered a 40% lower dose compared with the Western population, thereby providing a quantitative clinical pharmacology bridging and regional dosing rationale for global drug development.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Asian People; Aurora Kinase A; Azepines; Biological Availability; Diarrhea; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Incidence; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Neutropenia; Protein Kinase Inhibitors; Pyrimidines; Stomatitis; Young Adult

Transcriptional co-activators YES-associated protein (YAP) and transcriptional coactivator with PDZ-motif (TAZ) stimulate the expression of cell cycle-related genes to permit for tumour cell growth. MLN8237 is a potent aurora-A kinase inhibitor; however, patients responding to MLN8237 are limited. Therefore, rational combination therapy could enhance their response.. YAP and TAZ were depleted using siRNA and then treated with MLN8237 in YAP/TAZ-dependent OVCAR-8 and MDA-MB-231 cell lines. MLN8237 was combined with fluvastatin, an agent constraining nuclear localisation of YAP/TAZ for potential combination therapy in vitro.. Depletion of either YAP or TAZ sensitised these cell lines to MLN8237, resulting in apoptosis and reduction in aurora-A. MLN8237 reduced YAP/TAZ expression. A combination of MLN8237 with fluvastatin effectively reduced the cell viability of OVCAR-8 and MDA-MB-231 cell lines.. A combination of MLN8237 and small-molecule agents inactivating YAP/TAZ, such as statins, could be a novel therapeutic strategy for YAP/TAZ-dependent cancer.

Topics: Adaptor Proteins, Signal Transducing; Apoptosis; Aurora Kinase A; Azepines; Cell Line, Tumor; Cell Survival; Drug Synergism; Fatty Acids, Monounsaturated; Fluvastatin; Gene Expression Regulation, Neoplastic; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Indoles; Intracellular Signaling Peptides and Proteins; Neoplasms; Phosphoproteins; Pyrimidines; RNA Interference; Trans-Activators; Transcription Factors; Transcriptional Coactivator with PDZ-Binding Motif Proteins; YAP-Signaling Proteins

De novo and acquired resistance to platinum therapy such as cisplatin (CDDP) is a clinical challenge in gastric cancer treatment. Aberrant expression and activation of aurora kinase A (AURKA) and eukaryotic translation initiation factor 4E (eIF4E) are detected in several cancer types. Herein, we investigated the role of AURKA in CDDP resistance in gastric cancer. Western blot analysis demonstrated overexpression of AURKA and phosphorylation of eIF4E in acquired and de novo CDDP-resistant gastric cancer models. Inhibition of AURKA with MLN8237 (alisertib) alone or in combination with CDDP significantly suppressed viability of CDDP-resistant cancer cells (P < 0.01). Additionally, inhibition or knockdown of AURKA decreased protein expression of p-eIF4E (S209), HDM2, and c-MYC in CDDP-resistant cell models. This was associated with a significant decrease in cap-dependent translation levels (P < 0.01). In vivo tumor xenografts data corroborated these results and confirmed that inhibition of AURKA was sufficient to overcome CDDP resistance in gastric cancer. Our data demonstrate that AURKA promotes acquired and de novo resistance to CDDP through regulation of p-eIF4E (S209), c-MYC, HDM2, and cap-dependent translation. Targeting AURKA could be an effective therapeutic approach to overcome CDDP resistance in refractory gastric cancer and possibly other cancer types.

Topics: Animals; Aurora Kinase A; Azepines; Cell Line, Tumor; Cisplatin; Drug Resistance, Neoplasm; Female; Humans; Mice; Mice, Nude; Neoplasm Proteins; Neoplasms; Pyrimidines; Xenograft Model Antitumor Assays

Topics: Aurora Kinase A; Azepines; Humans; Neoplasms; Polymorphism, Single Nucleotide; Precision Medicine; Protein Kinase Inhibitors; Pyrimidines

Myc family proteins promote cancer by inducing widespread changes in gene expression. Their rapid turnover by the ubiquitin-proteasome pathway is regulated through phosphorylation of Myc Box I and ubiquitination by the E3 ubiquitin ligase SCF

Topics: Aurora Kinase A; Azepines; Binding Sites; Catalytic Domain; Crystallography, X-Ray; Humans; N-Myc Proto-Oncogene Protein; Neoplasms; Phenylurea Compounds; Phosphorylation; Polyubiquitin; Protein Binding; Protein Kinase Inhibitors; Pyrimidines; SKP Cullin F-Box Protein Ligases

The Aurora family of serine/threonine kinases is essential for mitosis. Their crucial role in cell cycle regulation and aberrant expression in a broad range of malignancies have been demonstrated and have prompted intensive search for small molecule Aurora inhibitors. Indeed, over 10 of them have reached the clinic as potential anticancer therapies. We report herein the discovery and optimization of a novel series of tricyclic molecules that has led to SAR156497, an exquisitely selective Aurora A, B, and C inhibitor with in vitro and in vivo efficacy. We also provide insights into its mode of binding to its target proteins, which could explain its selectivity.

Topics: Animals; Antineoplastic Agents; Aurora Kinase A; Aurora Kinase B; Aurora Kinase C; Aurora Kinases; Benzimidazoles; Female; HCT116 Cells; Humans; Mice, SCID; Models, Chemical; Models, Molecular; Molecular Structure; Neoplasms; Protein Binding; Protein Kinase Inhibitors; Protein Structure, Tertiary; Quinolones; Sf9 Cells; Small Molecule Libraries; Xenograft Model Antitumor Assays

Immunohistochemistry-based biomarkers are commonly used to understand target inhibition in key cancer pathways in preclinical models and clinical studies. Automated slide-scanning and advanced high-throughput image analysis software technologies have evolved into a routine methodology for quantitative analysis of immunohistochemistry-based biomarkers. Alongside the traditional pathology H-score based on physical slides, the pathology world is welcoming digital pathology and advanced quantitative image analysis, which have enabled tissue- and cellular-level analysis. An automated workflow was implemented that includes automated staining, slide-scanning, and image analysis methodologies to explore biomarkers involved in 2 cancer targets: Aurora A and NEDD8-activating enzyme (NAE). The 2 workflows highlight the evolution of our immunohistochemistry laboratory and the different needs and requirements of each biological assay. Skin biopsies obtained from MLN8237 (Aurora A inhibitor) phase 1 clinical trials were evaluated for mitotic and apoptotic index, while mitotic index and defects in chromosome alignment and spindles were assessed in tumor biopsies to demonstrate Aurora A inhibition. Additionally, in both preclinical xenograft models and an acute myeloid leukemia phase 1 trial of the NAE inhibitor MLN4924, development of a novel image algorithm enabled measurement of downstream pathway modulation upon NAE inhibition. In the highlighted studies, developing a biomarker strategy based on automated image analysis solutions enabled project teams to confirm target and pathway inhibition and understand downstream outcomes of target inhibition with increased throughput and quantitative accuracy. These case studies demonstrate a strategy that combines a pathologist's expertise with automated image analysis to support oncology drug discovery and development programs.

Topics: Algorithms; Animals; Apoptosis; Aurora Kinase A; Automation; Azepines; Biomarkers, Pharmacological; Biopsy; Cyclopentanes; Drug Discovery; Drug Evaluation, Preclinical; Humans; Image Processing, Computer-Assisted; Immunohistochemistry; Mitosis; Neoplasms; Pyrimidines; Skin

To gain a greater understanding of the potential of the Aurora kinase A inhibitor MLN8237 in the treatment of pediatric malignancies.. The activity of MLN8237 was evaluated against 28 neuroblastoma and Ewing sarcoma cell lines, and its in vivo efficacy was studied over a range of doses against 12 pediatric tumor xenograft models. Pharmacokinetic, pharmacodynamic, and genomic studies were undertaken.. In vitro neuroblastoma cell lines were generally more sensitive to MLN8237 than Ewing sarcoma lines. MLN8237 demonstrated significant activity in vivo against solid tumor models at the maximum tolerated dose (MTD); however, only 2 of 6 neuroblastoma models had objective responses at 0.25MTD. In contrast, MLN8237 induced objective responses at its MTD and at 0.5MTD in three ALL models and in two out of three at 0.25MTD. Pharmacokinetic studies at 0.5MTD demonstrated a T (max) of 0.5 h, C (max) of 24.8 μM, AUC((0-24)) of 60.3 μM h, and 12 h trough level of 1.2 μM. Mitotic indices increased 6-12 h after MLN8237 administration. AURKA copy number variation was frequent in xenografts, and expression was highly correlated with copy number.. Objective responses were more frequent in tumors with decreased AURKA copy number (5/8) compared to those with increased gene copy number (2/14). This report confirms the significant activity against both solid tumor and ALL xenografts at the MTD, with a steep dose response. These data support clinical development of MLN8237 in childhood cancer. Because of the steep dose-response relationship, such studies should target achieving trough levels of 1 μM or higher for sustained periods of treatment.

Topics: Animals; Aurora Kinase A; Aurora Kinases; Azepines; Cell Line, Tumor; Child; Dose-Response Relationship, Drug; Enzyme Inhibitors; Female; Gene Dosage; Humans; Mice; Mice, SCID; Neoplasms; Protein Serine-Threonine Kinases; Pyrimidines

Small-molecule inhibitors of Aurora A (AAK) and B (ABK) kinases, which play important roles in mitosis, are currently being pursued in oncology clinical trials. We developed three novel assays to quantitatively measure biomarkers of AAK inhibition in vivo. Here, we describe preclinical characterization of alisertib (MLN8237), a selective AAK inhibitor, incorporating these novel pharmacodynamic assays.. We investigated the selectivity of alisertib for AAK and ABK and studied the antitumor and antiproliferative activity of alisertib in vitro and in vivo. Novel assays were used to assess chromosome alignment and mitotic spindle bipolarity in human tumor xenografts using immunofluorescent detection of DNA and alpha-tubulin, respectively. In addition, 18F-3'-fluoro-3'-deoxy-l-thymidine positron emission tomography (FLT-PET) was used to noninvasively measure effects of alisertib on in vivo tumor cell proliferation.. Alisertib inhibited AAK over ABK with a selectivity of more than 200-fold in cells and produced a dose-dependent decrease in bipolar and aligned chromosomes in the HCT-116 xenograft model, a phenotype consistent with AAK inhibition. Alisertib inhibited proliferation of human tumor cell lines in vitro and produced tumor growth inhibition in solid tumor xenograft models and regressions in in vivo lymphoma models. In addition, a dose of alisertib that caused tumor stasis, as measured by volume, resulted in a decrease in FLT uptake, suggesting that noninvasive imaging could provide value over traditional measurements of response.. Alisertib is a selective and potent inhibitor of AAK. The novel methods of measuring Aurora A pathway inhibition and application of tumor imaging described here may be valuable for clinical evaluation of small-molecule inhibitors.

Topics: Animals; Aurora Kinase A; Aurora Kinases; Azepines; Cell Line, Tumor; Cell Proliferation; Dideoxynucleosides; Female; Fluorine Radioisotopes; HCT116 Cells; HeLa Cells; Humans; Lymphoma; Mice; Mice, Nude; Mice, SCID; Mitotic Index; Molecular Structure; Neoplasms; Phosphorylation; Positron-Emission Tomography; Protein Serine-Threonine Kinases; Pyrimidines; Spindle Apparatus; Tumor Burden; Xenograft Model Antitumor Assays

Topics: Animals; Antineoplastic Agents; Aurora Kinase A; Aurora Kinases; Azepines; Cell Proliferation; Drug Screening Assays, Antitumor; Humans; Mice; Neoplasms; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Pyrimidines