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Triple-negative breast cancers (TNBC) have an aggressive phenotype with a relatively high rate of recurrence and poor overall survival. To date, there is no approved targeted therapy for TNBCs. Aurora kinases act as regulators of mammalian cell division. They are important for cell-cycle progression and are frequently overexpressed or mutated in human tumors, including breast cancer. In this study, we investigated the therapeutic potential of targeting Aurora kinases in preclinical models of human breast cancers using a pan-inhibitor of Aurora kinases, AS703569. In vitro, AS703569 was tested in 15 human breast cancer cell lines. TNBC cell lines were more sensitive to AS703569 than were other types of breast cancer cells. Inhibition of proliferation was associated with cell-cycle arrest, aneuploidy, and apoptosis. In vivo, AS703569 administered alone significantly inhibited tumor growth in seven of 11 patient-derived breast cancer xenografts. Treatment with AS703569 was associated with a decrease of phospho-histone H3 expression. Finally, AS703569 combined to doxorubicin–cyclophosphamide significantly inhibited in vivo tumor recurrence, suggesting that Aurora kinase inhibitors could be used both in monotherapy and in combination settings. In conclusion, these data indicate that targeting Aurora kinases could represent a new effective approach for TNBC treatment. Mol Cancer Ther; 11(12); 2693–703. ©2012 AACR.

The mesenchymal–epithelial transition factor (MET) proto-oncogene encodes the MET receptor tyrosine kinase. MET aberrations drive tumorigenesis in several cancer types through a variety of molecular mechanisms including MET mutations, gene amplification, rearrangement, and overexpression. Therefore, MET is a therapeutic target and the selective type Ib MET inhibitor, tepotinib, was designed to potently inhibit MET kinase activity. In vitro, tepotinib inhibits MET in a concentration-dependent manner irrespective of the mode of MET activation, and in vivo, tepotinib exhibits marked, dose-dependent antitumor activity in MET-dependent tumor models of various cancer indications. Tepotinib penetrates the blood–brain barrier and demonstrates strong anti-tumor activity in subcutaneous and orthotopic brain metastasis models, in-line with clinical activity observed in patients. MET amplification is an established mechanism of resistance to EGFR tyrosine kinase inhibitors (TKIs) and preclinical studies show that tepotinib in combination with EGFR TKIs can overcome this resistance. Tepotinib is currently approved for the treatment of adult patients with advanced or metastatic non-small cell lung cancer harboring METex14 skipping alterations. This review focuses on the pharmacology of tepotinib in preclinical cancer models harboring MET alterations, and demonstrates that strong adherence to the principles of the Pharmacological Audit Trail may result in a successful discovery and development of a precision medicine.

Central nervous system-penetrant therapies with intracranial efficacy against non-small cell lung cancer (NSCLC) brain metastases are urgently needed. We report preclinical studies investigating brain penetration and intracranial activity of the MET inhibitor tepotinib. After intravenous infusion of tepotinib in Wistar rats (n = 3), mean (±standard deviation) total tepotinib concentration was 2.87-fold higher in brain (505 ± 22 ng/g) than plasma (177 ± 20 ng/mL). In equilibrium dialysis experiments performed in triplicate, mean tepotinib unbound fraction was 0.35% at 0.3 and 3.0 µM tepotinib in rat brain tissue, and 4.0% at 0.3 and 1.0 µM tepotinib in rat plasma. The calculated unbound brain-to-plasma ratio was 0.25, indicating brain penetration sufficient for intracranial target inhibition. Of 20 screened subcutaneous patient-derived xenograft (PDX) models from lung cancer brain metastases (n = 1), two NSCLC brain metastases models (LU5349 and LU5406) were sensitive to the suboptimal dose of tepotinib of 30 mg/kg/qd (tumor volume change [%TV]: -12% and -88%, respectively). Molecular profiling (nCounter®; NanoString) revealed high-level MET amplification in both tumors (mean MET gene copy number: 11.2 and 24.2, respectively). Tepotinib sensitivity was confirmed for both subcutaneous models at a clinically relevant dose (125 mg/kg/qd; n = 5). LU5349 and LU5406 were orthotopically implanted into brains of mice and monitored by magnetic resonance imaging (MRI). Tepotinib 125 mg/kg/qd induced pronounced tumor regression, including complete or near-complete regressions, compared with vehicle in both orthotopic models (n = 10; median %TV: LU5349, -84%; LU5406, -63%). Intracranial antitumor activity of tepotinib did not appear to correlate with blood-brain barrier leakiness assessed in T1-weighted gadolinium contrast-enhanced MRI.

Herein, we report the discovery of a novel class of quinazoline carboxamides as dual p70S6k/Akt inhibitors for the treatment of tumors driven by alterations to the PI3K/Akt/mTOR (PAM) pathway. Through the screening of in-house proprietary kinase library, 4-benzylamino-quinazoline-8-carboxylic acid amide 1 stood out, with sub-micromolar p70S6k biochemical activity, as the starting point for a structurally enabled p70S6K/Akt dual inhibitor program that led to the discovery of M2698, a dual p70S6k/Akt inhibitor. M2698 is kinase selective, possesses favorable physical, chemical, and DMPK profiles, is orally available and well tolerated, and displayed tumor control in multiple in vivo studies of PAM pathway-driven tumors.

Activation of the PI3K/Akt/mTOR kinase pathway is associated with human cancers. A dual p70S6K/Akt inhibitor is sufficient to inhibit strong tumor growth and to block negative impact of the compensatory Akt feedback loop activation. A scaffold docking strategy based on an existing quinazoline carboxamide series identified 4-aminopyrimidine analog 6, which showed a single-digit nanomolar and a micromolar potencies in p70S6K and Akt enzymatic assays. SAR optimization improved Akt enzymatic and p70S6K cellular potencies, reduced hERG liability, and ultimately discovered the promising candidate 37, which exhibited with a single digit nanomolar value in both p70S6K and Akt biochemical assays, and hERG activities (IC50 = 17.4 μM). This agent demonstrated dose-dependent efficacy in inhibiting mice breast cancer tumor growth and covered more than 90% pS6 inhibition up to 24 h at a dose of 200 mg/kg po.

The influence of the 2008 election of President Barack Obama on the naming of children born to African American mothers was investigated. Results indicated that children born after the election were given names that sounded more ‘African American’ than were children born before the election. In addition, African American mother’s Collective Self-Esteem scores were positively correlated with the ethnic sound of a child’s name. It was concluded that this difference in naming behaviour could be viewed through a social identity theory approach and might indicate a desire to ‘bask in the reflected glory’ of President Obama’s election.

Background Patients with advanced non-small cell lung cancer (NSCLC) harboring oncogenic MET alterations, such as MET exon 14 skipping or MET amplification (MET amp), benefit from MET tyrosine kinase inhibitor (TKI) treatment. Brain metastases are common in patients with advanced NSCLC. In preclinical studies in rats, tepotinib had relatively high binding to brain tissue (fu br=0.4%, fu pl=4%) and free tepotinib concentrations in brain were 25% of the concentrations found in plasma (Kp u,u=0.25). In this study we investigated the efficacy of the MET TKIs tepotinib, capmatinib, savolitinib and crizotinib in mice implanted orthotopically with MET-dependent tumor explants derived from human NSCLC brain metastases. Methods The antitumor activity of tepotinib (30 mg/kg qd) was investigated in a screen of 21 subcutaneous lung cancer patient-derived xenograft (PDX) models of brain metastases grown in NOD-SCID mice (n=1/model). 20 of these tumors were retrospectively analyzed for cancer-specific mutations, gene copy number (GCN) and gene expression by Nanostring. 2 responding models, both found to harbor MET amp, were tested again subcutaneously in NOD-SCID mice treated with vehicle or tepotinib (125 mg/kg qd; n=5). Both models were orthotopically implanted into brains of NOD-SCID mice and tumor growth was monitored by MRI. Established tumors were treated with MET TKIs (n=10) tepotinib (125 mg/kg qd), capmatinib (30 mg/kg bid), savolitinib (60 mg/kg qd) or crizotinib (50 mg/kg qd). Results 2 of 21 subcutaneous PDX tumors (LU5406 and LU5349) regressed in response to tepotinib treatment. When implanted subcutaneously again into mice, both models regressed completely upon treatment with tepotinib. Molecular profiles revealed that these were the only tumors of the 20 models investigated by Nanostring that had MET amp (high-level increase in MET GCN of >10). Both models grew orthotopically when implanted into brains of mice. Contrast-weighted MRI indicated regions with intact and disrupted blood–brain barrier (BBB) in all implanted tumors. Tumor regression of orthotopic LU5406 tumors was observed with all MET TKIs (% median tumor volume changes [%TV]: tepotinib, –63%; capmatinib, –24%; savolitinib, –38%; crizotinib, –27%). In the orthotopic LU5349 tumors, treatment with crizotinib or savolitinib led to growth inhibition (%TV: +88% and –13%, respectively), whereas tepotinib and capmatinib induced tumor regression (%TV: –84% and –63%, respectively). Conclusions The heterogenous pattern of regions with intact and disrupted BBB in the orthotopic brain metastases models is thought to mirror the clinical situation. Tepotinib was efficacious in the two MET-driven orthotopic brain metastases PDX tumors characterized by pronounced tumor regression and may be relevant to patients with brain metastases. Relationships between efficacy and BBB leakiness will be discussed. Citation Format: Manja Friese-Hamim, Anderson Clark, Lindsey Crowley, Christof Reusch, Olga Bogatyrova, Claudia Wilm, Hong Zhang, Timothy Crandall, Jing Lin, Jianguo Ma, David Bachner, Jürgen Schmidt, Martin Schaefer, Christopher Stroh. Anti-tumor activity of tepotinib in orthotopic models of lung cancer patient-derived brain metastases with MET amplification [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3407.

Small Cell Lung Cancer (SCLC) is characterized by rapid tumor growth and currently, there are few therapeutic options or predictive biomarkers. Patient derived xenograft (PDX) models are capable of recapitulating solid tumor growth including the intra-tumor heterogeneity (ITH) observed in the original patient tumor. The present study aimed to correlate surface marker profiles of SCLC PDX models with previously observed drug responses to M2698, a potent, selective inhibitor of p70S6K and AKT 1/3, and investigate ITH through gene expression profiling of tumor cell subpopulations. Drug response data had been established in a preclinical screen of 45 PDX models of SCLC, in which two mice were implanted subcutaneously with tumors from each model; one mouse was treated with vehicle while the other was treated with M2698 25 mg/kg QD po until the tumor in the vehicle-treated mouse reached ~1200 mm3. Tumor control (stasis or regression) was seen in 12 (27%) of the models. We showed previously that cell surface marker profiles of PDX tumor tissue demonstrated high intra-model reproducibility for many surface markers and uniquely associate with each model. Also, distinctly heterogeneous markers were identified that allowed FACS sorting of tumor cell subpopulations with similarly distinct gene expression profiles. To build on these data, a subset of models that were the most and the least sensitive to M2698 (n=7) in the above described screen were selected for implantation into a new set of mice. Tumors were profiled once they reached ~800 mm3. We evaluated 80+ markers commonly used to identify tumor initiating cells (e.g. CD44, CD90, CD133, CD166, CD184), EMT or aggressiveness (e.g. CD166, EphB2, CD324, CD325), poor outcome in SCLC (CD49b, CD221, claudin3) or drug targets (e.g. CD184, EGFR, Her2) to establish extensive marker profiles. Our data reveal that surface marker profiles in these models allow a meaningful subclassification of SCLC PDX tissue. Correlation of these profiles with efficacy of M2698 (above) suggest that surface markers may have predictive value. Our results prequalify a number of these markers for validation. Furthermore, several models harbor cell subpopulations identifiable by various surface markers. Along with their distinct gene expression profiles this suggests an equilibrium between functionally different compartments within a lesion. In one case, the ratio of two populations shifted concurrently with growth differences, raising the possibility of a dynamic relationship between this equilibrium and the growth stage. Overall, our workflow may provide tools for sample characterization, quality control and elucidation of cellular response markers to varying selective pressures, such as drug challenges. Citation Format: Warren Porter, Eileen Snowden, Friedrich Hahn, Mitchell Ferguson, Frances Tong, William S. Dillmore, Anderson Clark, Hong Zhang, Rainer Blaesius. Surface protein marker and single cell gene expression profiling of individual tumor cells dissociated from small cell lung cancer pdx mouse models can be correlated with in vivo sensitivity to the p70S6K/AKT1/3 inhibitor M2698 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4710.