Purpose of review To review recent original data on leptomeningeal metastases in patients with solid cancer. Recent findings Lung and breast cancer as well as melanoma remain the most common primaries. Advanced cytological methods and targeted sequencing for candidate tumor-specific mutations may improve the sensitivity of cerebrospinal fluid diagnostics in leptomeningeal metastases. Targeted treatments like epidermal growth factor receptor tyrosine kinase inhibitors for non-small cell lung cancer, anti-human epidermal growth factor receptor-2 treatments for breast cancer or B-rapidly accelerated fibrosarcoma-targeted or immunotherapy for melanoma have an emerging role in the management of this condition. Summary Novel diagnostic approaches and the introduction of targeted agents may improve the clinical management of patients with leptomeningeal metastases from solid cancers.
Abstract 3313: Pharmacologic targeting of Aurora-A kinase restores ERα expression and endocrine sensitivity through impairment of breast cancer stemness
Cancer Research | July 26, 2016 | Volume: 76 | Issue: 14_Supplement | Pages: 3313-3313
Abstract Background: Intrinsic resistance has been linked to ER down-regulation and poor clinical outcome in breast tumors. Aurora-A kinase (AURKA) promotes distant metastases through activation of epithelial to mesenchymal transition (EMT) programming and expansion of breast tumor initiating cells (BTICs) harboring a CD44high/CD24low phenotype. Moreover, AURKA induces down-regulation of ERα expression and resistance to endocrine therapy that is mediated by SMAD5 transcription factor (D’Assoro et al., Oncogene 2014: 33:599-610). The aim of this study was to evaluate the role of AURKA in endocrine resistance induced by breast cancer stemness and ER down-regulation. Materials and Methods: We employed parental MCF-7 and variant MCF-7 cells ex-vivo (vMCF- 7/LCC9, vMCF-7/FR) that have high endogenous levels of AURKA, are ERlow, and exhibit in vivo resistance to fulvestrant. Real-Time Cell Proliferation and Apoptosis assays were performed to assess response to endocrine and/or AURKA-targeted therapy using the innovative IncuCyte ZOOM System. Stemness activity was assessed by culturing breast cancer cells under non-adherent conditions to generate mammospheres. Expression of ER, CD44 and CD24 markers was characterized by FACS analysis and immunofluorescence. Results: Pharmacologic inhibition of AURKA activity with the small molecule, alisertib, significantly restored sensitivity to fulvestrant in vMCF-7/LCC9 and vMCF-7/FR cells. To establish whether fulvestrant resistance was linked to enrichment of BTICs, breast cancer cells were cultured under non-adherent conditions to generate mammospheres. vMCF-7/FR cells generated mammospheres at higher efficiency compared to parental cells suggesting that vMCF-7/FR cells exhibited high self-renewal activity. vMCF-7/FR-derived mammospheres displayed a stem cell-like CD44high/CD24low phenotype that was further characterized by low levels of ER expression and resistance to fulvestrant. When vMCF-7 FR-derived mammospheres were treated with alisertib alone or combined with fulvestrant, the combination was more effective in mediating restoration of endocrine sensitivity. The phenotype of the alisertib-treated mammospheres was functionally linked to loss of CD44 expression, restoration of CD24 and ER expression, and sensitivity to fulvestrant. Conclusions: These findings provide further evidence that AURKA activity plays a central role in breast cancer progression through the genesis and clonal expansion of BTICs that are characterized by ER down-regulation and resistance to endocrine therapy. These results are important for the treatment of endocrine resistant breast tumors because they provide the rationale for the development of an innovative therapeutic approach to combine endocrine therapy with a targeted inhibitor of AURKA activity. Citation Format: Antonino B. D’Assoro, Tufia Haddad, Matthew Goetz, Mary Kuffel, John Hawse, Vera Suman, Jeffrey Salisbury, James Ingle, Evanthia Galanis. Pharmacologic targeting of Aurora-A kinase restores ERα expression and endocrine sensitivity through impairment of breast cancer stemness. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3313.
Effect of Radiosurgery Alone vs Radiosurgery With Whole Brain Radiation Therapy on Cognitive Function in Patients With 1 to 3 Brain Metastases
AbstractThe population pharmacokinetic model reported here was developed using data from 2 phase 2 trials of irinotecan for treatment of malignant glioma to quantify the impact of concomitant therapy with enzyme‐inducing antiepileptic drugs (EIAEDs) on irinotecan pharmacokinetics. Patients received weekly irinotecan doses of 100 to 400 mg/m2, and plasma samples were collected and analyzed for irinotecan and its APC, SN‐38, and SN‐38G metabolites. Nonlinear mixed‐effects modeling was employed for population pharmacokinetic analysis. Concomitant therapy with phenytoin, phenobarbital, or carbamazepine increased the clearances of irinotecan, SN‐38, and SN‐38G but not APC. SN‐38 clearance was 2‐fold higher with concomitant EIAED use, resulting in 40% lower SN‐38 exposure. Evaluation of additional covariates revealed no clinically relevant effects of sex or concomitant corticosteroid use. The population pharmacokinetic model suggests that a 1.7‐fold increase in irinotecan dose may compensate for decreases in SN‐38 exposure in the presence of concomitant EIAEDs. Although slightly more conservative, this dose adjustment is consistent with those recommended based on increases in the maximally tolerated dose for malignant glioma patients receiving EIAEDs and may be an appropriate starting point for further investigation when extrapolating to other cancer types or alternative regimens.
Oncolytic Measles Virus Expressing the Sodium Iodide Symporter to Treat Drug-Resistant Ovarian Cancer
Cancer Research | November 15, 2014 | Volume: 75 | Issue: 1 | Pages: 22-30