Exclusion of Patients With Brain Metastases in Published Phase III Clinical Trials for Advanced Breast Cancer.

Metastatic HER2-positive (HER2+) and triple-negative breast cancer (TNBC) confer a 30% or higher risk of developing brain metastases (BrM), but BrM is typically an exclusion criteria for clinical trials, which limits the generalizability of trial results to these patients. We therefore analysed trends in the enrollment of patients with BrM, as well as the use of outcomes specific to the central nervous system (CNS), in phase III clinical trials evaluating systemic therapy for patients with advanced HER2+ and/or TNBC. Notably, 10 of the 34 trials (29%, 95% confidence interval = 15.1%-47.5%) evaluated CNS-specific outcomes and trials that completely excluded patients with BrM were significantly less likely to meet their primary endpoint (n = 6/17, 35%) than those that permitted conditional enrollment (n = 13/15, 87%) (P = .005), suggesting that enrollment of patients with BrM is not detrimental to trial success.

Evaluation of the impact of patient involvement in health technology assessments: A scoping review.

OBJECTIVES: While involving patients in health technology assessment (HTA) has become increasingly common and important around the world, little is known about the optimal methods of evaluating patients' involvement (PI) in HTA. This scoping review was undertaken to provide an overview of currently available methods for the evaluation of PI, specifically the impact of PI on HTA recommendations. METHODS: A literature search was conducted using nine databases as well as a grey literature search of the websites of 26 organizations related to the conduct, practice or research of HTA to identify articles, reports and abstracts related to the evaluation of PI impact in HTA. RESULTS: We identified 1,248 unique citations, six of which met our eligibility criteria. These six records (five articles, and one report) were all published after 2012. Four assessed the impact of patient experience submissions on final HTA recommendations; one evaluated the impact of direct involvement on HTA committees, and one assessed impact of multiple forms of involvement. Methods of evaluation included quantitative analyses of reimbursement decisions, qualitative interviews with those directly involved in an assessment, surveys of patient groups and committee members, and the review of HTA reports. CONCLUSIONS: Quantitative evaluation of PI based on associations with funding decisions may not be feasible or fully capture the relevant impact of PI in the assessment of health technologies. Rather, a combination of both qualitative and quantitative strategies may allow for the most comprehensive assessment of the impact of PI on HTA recommendations when possible.

Central nervous system-specific efficacy of CDK4/6 inhibitors in randomized controlled trials for metastatic breast cancer.

Importance: Metastatic breast cancer with central nervous system (CNS) metastases carries a poor prognosis. Recently, CDK4/6 inhibitors have demonstrated a progression free survival (PFS) and overall survival benefit when combined with standard endocrine therapy in advanced hormone receptor (HR)+/HER2- breast cancer. Pre-clinical data suggests possible activity of CDK4/6 inhibitors in the brain, but their CNS-specific benefit has not been explored in clinical practice. Methods: We reviewed clinical trials investigating the efficacy of CDK4/6 inhibitors for advanced or metastatic HR+/HER2- breast cancer. We also reviewed pre-clinical studies that demonstrated the ability of CDK4/6 inhibitors to cross the blood-brain barrier (BBB) and halt the growth of brain metastases in animal models. Findings: An ongoing phase II trial (NCT02308020) was designed to investigate the safety and tolerability of abemaciclib for treatment of patients with CNS metastases, with preliminary data showing partial response in some patients. Review of key randomized phase III trials revealed a scarcity of data pertaining to the development of new CNS metastases. Pre-clinical models demonstrate that CDK4/6 inhibitors are able to cross the BBB and can delay the growth of brain metastases. Conclusions: Despite encouraging pre-clinical evidence, there is a lack of clinical data to inform CNS-specific response rates to CDK4/6 inhibitors among patients with metastatic breast cancer. Given that the treatment of patients with breast cancer brain metastases represents an area of unmet medical need, enrollment of patients with CNS metastases in ongoing clinical trials should be encouraged; innovative trials that examine response of CNS metastases to CDK4/6 inhibitors are also of interest.

Invadopodia are chemosensing protrusions that guide cancer cell extravasation to promote brain tropism in metastasis.

Invadopodia are cell protrusions that mediate cancer cell extravasation but the microenvironmental cues and signaling factors that induce invadopodia formation during extravasation remain unclear. Using intravital imaging and loss of function experiments, we determined invadopodia contain receptors involved in chemotaxis, namely GABA receptor and EGFR. These chemotaxis capabilities are mediated in part by PAK1 which controls invadopodia responsiveness to ligands such as GABA and EGF via assembly, stability, and turnover of invadopodia in vivo. PAK1 knockdown rendered cells unresponsive to chemotactic stimuli present in the stroma, resulting in dramatically lower rates of cancer cell extravasation and metastatic colony formation compared to stimulated cancer cells. In an experimental mouse model of brain metastasis, inhibition of PAK1 significantly reduced overall tumor burden and reduced the average size of brain metastases. In summary, invadopodia contain chemotaxis receptors that can respond to microenvironmental cues to guide cancer cell extravasation, and when PAK1 is depleted, brain tropism of metastatic breast cancer cells is significantly reduced, blocking secondary colony growth at sites otherwise permissive for metastatic outgrowth.

Lestaurtinib is a potent inhibitor of anaplastic thyroid cancer cell line models.

Anaplastic thyroid cancer (ATC) is a rare and lethal human malignancy with no known effective therapies in the majority of cases. Despite the use of conventional treatments such as chemotherapy, radiation and surgical resection, this disease remains almost universally fatal. In the present study, we identified the JAK2 inhibitor Lestaurtinib as a potent compound when testing against 13 ATC cell lines. Lestaurtinib demonstrated a potent antiproliferative effect in vitro at nanomolar concentrations. Furthermore, Lestaurtinib impeded cell migration and the ability to form colonies from single cells using scratch-wound and colony formation assays, respectively. Flow cytometry was used for cell cycle analysis following drug treatment and demonstrated arrest at the G2/M phase of the cell cycle, indicative of a cytostatic effect. In vivo studies using the chick chorioallantoic membrane xenograft models demonstrated that treatment with Lestaurtinib resulted in a significant decrease in endpoint tumor volume and vascularity using power Doppler ultrasound imaging. Overall, this study provides evidence that Lestaurtinib is a potent antiproliferative agent with potential antiangiogenic activity that warrants further investigation as a targeted therapy for ATC.