buparlisib and Brain-Neoplasms

To estimate the maximum tolerated dose (MTD) and/or identify the recommended Phase II dose (RP2D) for combined INC280 and buparlisib in patients with recurrent glioblastoma with homozygous phosphatase and tensin homolog (PTEN) deletion, mutation or protein loss.. This multicenter, open-label, Phase Ib/II study included adult patients with glioblastoma with mesenchymal-epithelial transcription factor (c-Met) amplification. In Phase Ib, patients received INC280 as capsules or tablets in combination with buparlisib. In Phase II, patients received INC280 only. Response was assessed centrally using Response Assessment in Neuro-Oncology response criteria for high-grade gliomas. All adverse events (AEs) were recorded and graded.. 33 patients entered Phase Ib, 32 with altered PTEN. RP2D was not declared due to potential drug-drug interactions, which may have resulted in lack of efficacy; thus, Phase II, including 10 patients, was continued with INC280 monotherapy only. Best response was stable disease in 30% of patients. In the selected patient population, enrollment was halted due to limited activity with INC280 monotherapy. In Phase Ib, the most common treatment-related AEs were fatigue (36.4%), nausea (30.3%) and increased alanine aminotransferase (30.3%). MTD was identified at INC280 Tab 300 mg twice daily + buparlisib 80 mg once daily. In Phase II, the most common AEs were headache (40.0%), constipation (30.0%), fatigue (30.0%) and increased lipase (30.0%).. The combination of INC280/buparlisib resulted in no clear activity in patients with recurrent PTEN-deficient glioblastoma. More stringent molecular selection strategies might produce better outcomes.. NCT01870726.

Topics: Adult; Aged; Aminopyridines; Antineoplastic Combined Chemotherapy Protocols; Benzamides; Brain Neoplasms; Female; Follow-Up Studies; Glioblastoma; Humans; Imidazoles; Male; Maximum Tolerated Dose; Middle Aged; Morpholines; Neoplasm Recurrence, Local; Prognosis; Proto-Oncogene Proteins c-met; PTEN Phosphohydrolase; Tissue Distribution; Triazines

Phosphatidylinositol 3-kinase (PI3K) signaling is highly active in glioblastomas. We assessed pharmacokinetics, pharmacodynamics, and efficacy of the pan-PI3K inhibitor buparlisib in patients with recurrent glioblastoma with PI3K pathway activation.. This study was a multicenter, open-label, multi-arm, phase II trial in patients with PI3K pathway-activated glioblastoma at first or second recurrence. In cohort 1, patients scheduled for re-operation after progression received buparlisib for 7 to 13 days before surgery to evaluate brain penetration and modulation of the PI3K pathway in resected tumor tissue. In cohort 2, patients not eligible for re-operation received buparlisib until progression or unacceptable toxicity. Once daily oral buparlisib 100 mg was administered on a continuous 28-day schedule. Primary end points were PI3K pathway inhibition in tumor tissue and buparlisib pharmacokinetics in cohort 1 and 6-month progression-free survival (PFS6) in cohort 2.. Sixty-five patients were treated (cohort 1, n = 15; cohort 2, n = 50). In cohort 1, reduction of phosphorylated AKT. Buparlisib had minimal single-agent efficacy in patients with PI3K-activated recurrent glioblastoma. Although buparlisib achieved significant brain penetration, the lack of clinical efficacy was explained by incomplete blockade of the PI3K pathway in tumor tissue. Integrative results suggest that additional study of PI3K inhibitors that achieve more-complete pathway inhibition may still be warranted.

Topics: Adult; Aged; Aged, 80 and over; Aminopyridines; Antineoplastic Agents; Brain Neoplasms; Chemotherapy, Adjuvant; Disease Progression; Enzyme Activation; Female; Glioblastoma; Humans; Male; Middle Aged; Morpholines; Neoadjuvant Therapy; Neoplasm Recurrence, Local; Phosphatidylinositol 3-Kinase; Phosphoinositide-3 Kinase Inhibitors; Progression-Free Survival; Time Factors

A Phase Ib study in patients with trastuzumab-resistant, human epidermal growth factor receptor-2- (HER2)-positive advanced breast cancer defined the recommended Phase II dose of buparlisib as 100 mg/day in combination with 2 mg/kg weekly trastuzumab, and reported preliminary signs of clinical activity. Here we present results from the Phase II portion.. Patients with trastuzumab-resistant, HER2-positive advanced breast cancer received buparlisib plus trastuzumab. Study endpoints included safety/tolerability and antitumour activity. The study was extended to include a Phase Ib dose-escalation phase, in which patients with progressive brain metastases also received capecitabine.. In the Phase II portion, of 50 patients treated with buparlisib and trastuzumab, the most common (≥ 30%) all-grade adverse events (AEs) were diarrhoea (54%), nausea (48%), decreased appetite, increased alanine aminotransferase (36% each), increased aspartate aminotransferase (34%), fatigue, rash (32% each), cough and hyperglycemia (30% each). One (2%) patient achieved complete response and four (8%) patients had confirmed partial responses [PR; including two patients with phosphatidylinositol 3-kinase (PI3 K) pathway-activated tumours]. Overall response rate (ORR) was 10%: the primary endpoint (ORR ≥ 25%) was therefore not met. In the Phase Ib portion, all patients with measurable brain lesions at baseline showed tumour shrinkage to some degree; due to low enrollment, maximum tolerated dose of buparlisib in combination with trastuzumab and capecitabine was not determined.. Buparlisib plus trastuzumab, as a chemotherapy-free regimen, demonstrated an acceptable safety profile but limited efficacy in patients with heavily pretreated, trastuzumab-resistant HER2-positive breast cancer, and in patients with progressive brain metastases also receiving capecitabine.

Topics: Adult; Aged; Aminopyridines; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Brain Neoplasms; Breast Neoplasms; Capecitabine; Disease Progression; Drug Resistance, Neoplasm; Female; Humans; Maximum Tolerated Dose; Middle Aged; Morpholines; Receptor, ErbB-2; Response Evaluation Criteria in Solid Tumors; Trastuzumab

Malignant melanoma is the most aggressive type of skin cancer and is closely associated with the development of brain metastases. Despite aggressive treatment, the prognosis has traditionally been poor, necessitating improved therapies. In melanoma, the mitogen activated protein kinase and the phosphoinositide 3-kinase signaling pathways are commonly altered, and therapeutically inhibiting one of the pathways often upregulates the other, leading to resistance. Thus, combined treatment targeting both pathways is a promising strategy to overcome this. Here, we studied the in vitro and in vivo effects of the PI3K inhibitor buparlisib and the MEK1/2 inhibitor trametinib, used either as targeted monotherapies or in combination, on patient-derived melanoma brain metastasis cell lines. Scratch wound and trans-well assays were carried out to assess the migratory capacity of the cells upon drug treatment, whereas flow cytometry, apoptosis array and Western blots were used to study apoptosis. Finally, an in vivo treatment experiment was carried out on NOD/SCID mice. We show that combined therapy was more effective than monotherapy. Combined treatment also more effectively increased apoptosis, and inhibited tumor growth in vivo. This suggests a clinical potential of combined treatment to overcome ceased treatment activity which is often seen after monotherapies, and strongly encourages the evaluation of the treatment strategy on melanoma patients with brain metastases.

Topics: Aminopyridines; Animals; Antineoplastic Combined Chemotherapy Protocols; Brain Neoplasms; Cell Line, Tumor; Melanoma; Mice, Inbred NOD; Mice, SCID; Mitogen-Activated Protein Kinases; Morpholines; Phosphatidylinositol 3-Kinases; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Signal Transduction; Skin Neoplasms; Treatment Outcome; Tumor Burden; Xenograft Model Antitumor Assays

Mutations and activation of the PI3K signaling pathway in breast cancer cells have been linked to brain metastases. However, here we describe that in some breast cancer brain metastases samples the protein expression of PI3K signaling components is restricted to the metastatic microenvironment. In contrast to the therapeutic effects of PI3K inhibition on the breast cancer cells, the reaction of the brain microenvironment is less understood. Therefore we aimed to quantify the PI3K pathway activity in breast cancer brain metastasis and investigate the effects of PI3K inhibition on the central nervous system (CNS) microenvironment. First, to systematically quantify the PI3K pathway activity in breast cancer brain metastases, we performed a prospective biomarker study using a reverse phase protein array (RPPA). The majority, namely 30 out of 48 (62.5%) brain metastatic tissues examined, revealed high PI3K signaling activity that was associated with a median overall survival (OS) of 9.41 months, while that of patients, whose brain metastases showed only moderate or low PI3K activity, amounted to only 1.93 and 6.71 months, respectively. Second, we identified PI3K as a master regulator of metastasis-promoting macrophages/microglia during CNS colonization; and treatment with buparlisib (BKM120), a pan-PI3K Class I inhibitor with a good blood-brain-barrier penetrance, reduced their metastasis-promoting features. In conclusion, PI3K signaling is active in the majority of breast cancer brain metastases. Since PI3K inhibition does not only affect the metastatic cells but also re-educates the metastasis-promoting macrophages/microglia, PI3K inhibition may hold considerable promise in the treatment of brain metastasis and the respective microenvironment.

Topics: Adult; Aged; Aminopyridines; Animals; Brain Neoplasms; Breast Neoplasms; Calcium-Binding Proteins; Disease Models, Animal; Enzyme Inhibitors; Female; Gene Expression Regulation, Neoplastic; Glial Fibrillary Acidic Protein; Humans; Macrophages; Mice; Mice, Inbred BALB C; Microfilament Proteins; Microglia; Middle Aged; Morpholines; Phosphatidylinositol 3-Kinases; Signal Transduction; TOR Serine-Threonine Kinases

Glioblastoma is an aggressive, invasive tumor of the central nervous system (CNS). There is a widely acknowledged need for anti-invasive therapeutics to limit glioblastoma invasion. BKM-120 is a CNS-penetrant pan-class I phosphatidyl-inositol-3 kinase (PI3K) inhibitor in clinical trials for solid tumors, including glioblastoma. We observed that BKM-120 has potent anti-invasive effects in glioblastoma cell lines and patient-derived glioma cells in vitro. These anti-migratory effects were clearly distinguishable from cytostatic and cytotoxic effects at higher drug concentrations and longer durations of drug exposure. The effects were reversible and accompanied by changes in cell morphology and pronounced reduction in both cell/cell and cell/substrate adhesion. In vivo studies showed that a short period of treatment with BKM-120 slowed tumor spread in an intracranial xenografts. GDC-0941, a similar potent and selective PI3K inhibitor, only caused a moderate reduction in glioblastoma cell migration. The effects of BKM-120 and GDC-0941 were indistinguishable by in vitro kinase selectivity screening and phospho-protein arrays. BKM-120 reduced the numbers of focal adhesions and the velocity of microtubule treadmilling compared with GDC-0941, suggesting that mechanisms in addition to PI3K inhibition contribute to the anti-invasive effects of BKM-120. Our data suggest the CNS-penetrant PI3K inhibitor BKM-120 may have anti-invasive properties in glioblastoma.

Topics: Aminopyridines; Animals; Blood-Brain Barrier; Brain Neoplasms; Cell Adhesion; Cell Culture Techniques; Cell Line, Tumor; Cell Movement; Cell Proliferation; Enzyme Inhibitors; Glioblastoma; Humans; Mice; Mice, Nude; Microtubules; Morpholines; Neoplasm Invasiveness; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Spheroids, Cellular; Transplantation, Heterologous; Vimentin

Brain metastases represent the greatest clinical challenge in treating HER2-positive breast cancer. We report the development of orthotopic patient-derived xenografts (PDXs) of HER2-expressing breast cancer brain metastases (BCBM), and their use for the identification of targeted combination therapies. Combined inhibition of PI3K and mTOR resulted in durable tumor regressions in three of five PDXs, and therapeutic response was correlated with a reduction in the phosphorylation of 4EBP1, an mTORC1 effector. The two nonresponding PDXs showed hypermutated genomes with enrichment of mutations in DNA-repair genes, which suggests an association of genomic instability with therapeutic resistance. These findings suggest that a biomarker-driven clinical trial of PI3K inhibitor in combination with an mTOR inhibitor should be conducted for patients with HER2-positive BCBM.

Topics: Adaptor Proteins, Signal Transducing; Aminopyridines; Animals; Antineoplastic Agents; Apoptosis; Brain Neoplasms; Breast Neoplasms; Carrier Proteins; Caspase 3; Cell Cycle Proteins; DNA Repair; Drug Resistance, Neoplasm; Drug Therapy, Combination; Eukaryotic Initiation Factors; Everolimus; Female; Gene Expression Profiling; Genomic Instability; Humans; Immunohistochemistry; Ki-67 Antigen; Magnetic Resonance Imaging; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, SCID; Molecular Targeted Therapy; Morpholines; Multiprotein Complexes; Neoplasm Transplantation; Phosphoinositide-3 Kinase Inhibitors; Phosphoproteins; Phosphorylation; Receptor, ErbB-2; Remission Induction; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Glioblastomas (GBMs) are aggressive brain tumours with a dismal prognosis, despite combined surgery, radio- and chemotherapy. Close to 90 % of all GBMs harbour a deregulated PI3K pathway, which is essential in regulating central cellular functions such as proliferation, cell growth, motility and survival. Thus, PI3K represents a potential target for molecular therapy in GBM. We investigated the anti-tumour efficacy of the PI3K inhibitor buparlisib (NVP-BKM120) in GBM cell lines in vitro and in vivo, when treatment was initiated after MRI-confirmed tumour engraftment. We found that buparlisib inhibited glioma cell proliferation in a dose dependent manner, demonstrated by MTS assay, manual cell count and BrdU incorporation. A dose dependent increase in apoptosis was observed through flow cytometric analysis. Furthermore, by immunocytochemistry and western blot, we found a dose dependent inhibition of Akt phosphorylation. Moreover, buparlisib prolonged survival of nude rats harboring human GBM xenografts in three independent studies and reduced the tumours' volumetric increase, as determined by MRI. In addition, histological analyses of xenograft rat brains showed necrotic areas and change in tumour cell nuclei in buparlisib-treated animals. The rats receiving buparlisib maintained their weight, activity level and food- and water intake. In conclusion, buparlisib effectively inhibits glioma cell proliferation in vitro and growth of human GBM xenografts in nude rats. Moreover, the compound is well tolerated when administered at doses providing anti-tumour efficacy. Thus, buparlisib may have a future role in glioma therapy, and further studies are warranted to validate this compound for human use.

Topics: Aminopyridines; Animals; Antineoplastic Agents; Apoptosis; Brain Neoplasms; Cell Line, Tumor; Cell Proliferation; Cell Survival; Glioblastoma; Humans; Morpholines; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats, Nude; Survival Analysis; Xenograft Model Antitumor Assays

We previously observed that glioma cells are differentially sensitive to TRAIL-induced toxicity. Based on our observation that TRAIL-resistant glioma cell lines typically exhibited high levels of Akt activation, we hypothesized that inhibition of Akt signaling using the PI3 kinase inhibitor NVP-BKM120 could promote TRAIL-induced apoptosis in gliomas. We assessed this combination in established and primary cultured glioma cells. Combination treatment led to significant cellular death when compared to either drug alone, but had no effect in normal human astrocytes, and demonstrated activation of the caspase cascade. This enhanced apoptosis appears dependent upon the loss of mitochondrial membrane potential and the release of Smac/DIABLO, AIF and cytochrome c into the cytosol. The upregulation of Noxa and sequestration of Mcl-1 by Noxa were important factors for cell death. Knockdown of Noxa abrogated apoptosis and suggested dependency on Noxa in combination-induced apoptosis. BKM120 upregulated cell surface expression of death receptor 5 (DR5), but did not increase levels of the other major TRAIL receptor, death receptor 4 (DR4). This study demonstrates that antagonizing apoptosis-resistance pathways, such as the PI3/Akt pathway, in combination with death receptor activation, may induce cell death in TRAIL-resistant glioma.

Topics: Aminopyridines; Antineoplastic Agents; Apoptosis; Astrocytes; Brain Neoplasms; Cell Line, Tumor; Drug Resistance, Neoplasm; Drug Synergism; Glioma; Humans; Morpholines; Proto-Oncogene Proteins c-bcl-2; Receptors, TNF-Related Apoptosis-Inducing Ligand; TNF-Related Apoptosis-Inducing Ligand; Up-Regulation

Combined targeting with a PI3-kinase inhibitor, BKM120, and an Hsp90 inhibitor, HSP990, was investigated as a multi-targeted approach to potentiate cell death in glioblastoma (GBM). Additionally, the effect of dual drug treatment combined with cytotoxic stress (radiation therapy) was examined.. Four human GBM cell lines containing wild-type or mutated PTEN and/or p53 were studied. The effects of drug treatments on cell viability, apoptosis induction, pAKt activity, cell cycle arrest, clonogenicity, and tumor growth delay were studied.. Combined concurrent treatment with both drugs produced more cell killing in cell viability and apoptosis assays than either drug alone. BKM120 plus HSP990 induced suppression of baseline Akt signaling as well as radiation (RT)-induced pAkt signaling in all cell lines. Cell cycle analysis revealed that HSP990 and BKM120, singly or combined, induced G2/M arrest leading to apoptosis/necrosis and polyploidy. Additionally, the drugs radiosensitized GBM cells in clonogenic assays. In vivo tumor growth delay studies demonstrated the effectiveness of combined drug treatment with HSP990 and BKM120 over single drug treatment, as well as the effectiveness of combined drug treatment in enhancing the effectiveness of radiation therapy.. In conclusion, HSP990 and BKM120, with and without RT, are active agents against glioma tumors. The sensitivity to these agents does not appear to depend on PTEN/p53status in the cell lines tested. We suggest that the combined action of both drugs is a viable multi-targeted strategy with the potential to improve clinical outcome for patients with high-grade glioma.

Topics: Aminopyridines; Animals; Apoptosis; Blotting, Western; Brain Neoplasms; Cell Proliferation; Flow Cytometry; Gene Expression Regulation, Neoplastic; Glioblastoma; HSP90 Heat-Shock Proteins; Humans; Mice; Mice, Nude; Morpholines; Phosphatidylinositol 3-Kinase; Phosphoinositide-3 Kinase Inhibitors; Radiation Tolerance; Radiation-Sensitizing Agents; Tumor Cells, Cultured

In glioblastoma, phosphatidylinositol 3-kinase (PI3K) signaling is frequently activated by loss of the tumor suppressor phosphatase and tensin homolog (PTEN). However, it is not known whether inhibiting PI3K represents a selective and effective approach for treatment. We interrogated large databases and found that sonic hedgehog (SHH) signaling is activated in PTEN-deficient glioblastoma. We demonstrate that the SHH and PI3K pathways synergize to promote tumor growth and viability in human PTEN-deficient glioblastomas. A combination of PI3K and SHH signaling inhibitors not only suppressed the activation of both pathways but also abrogated S6 kinase (S6K) signaling. Accordingly, targeting both pathways simultaneously resulted in mitotic catastrophe and tumor apoptosis and markedly reduced the growth of PTEN-deficient glioblastomas in vitro and in vivo. The drugs tested here appear to be safe in humans; therefore, this combination may provide a new targeted treatment for glioblastoma.

Topics: Aminopyridines; Animals; Biphenyl Compounds; Brain Neoplasms; Cell Line, Tumor; Enzyme Inhibitors; Glioblastoma; Hedgehog Proteins; Humans; Mice; Mice, Nude; Morpholines; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; PTEN Phosphohydrolase; Pyridines; Ribosomal Protein S6 Kinases; Signal Transduction; Xenograft Model Antitumor Assays

The aim of this study was to show preclinical efficacy and clinical development potential of NVP-BKM120, a selective pan class I phosphatidylinositol-3 kinase (PI3K) inhibitor in human glioblastoma (GBM) cells in vitro and in vivo.. The effect of NVP-BKM120 on cellular growth was assessed by CellTiter-Blue assay. Flow cytometric analyses were carried out to measure the cell-cycle, apoptosis, and mitotic index. Mitotic catastrophe was detected by immunofluorescence. The efficacy of NVP-BKM120 was tested using intracranial U87 glioma model.. We tested the biologic effects of a selective PI3K inhibitor NVP-BKM120 in a set of glioma cell lines. NVP-BKM120 treatment for 72 hours resulted in a dose-dependent growth inhibition and effectively blocked the PI3K/Akt signaling cascade. Although we found no obvious relationship between the cell line's sensitivity to NVP-BKM120 and the phosphatase and tensin homolog (PTEN) and epidermal growth factor receptor (EGFR) statuses, we did observe a differential sensitivity pattern with respect to p53 status, with glioma cells containing wild-type p53 more sensitive than cells with mutated or deleted p53. NVP-BKM120 showed differential forms of cell death on the basis of p53 status of the cells with p53 wild-type cells undergoing apoptotic cell death and p53 mutant/deleted cells having a mitotic catastrophe cell death. NVP-BKM120 mediates mitotic catastrophe mainly through Aurora B kinase. Knockdown of p53 in p53 wild-type U87 glioma cells displayed microtubule misalignment, multiple centrosomes, and mitotic catastrophe cell death. Parallel to the assessment of the compound in in vitro settings, in vivo efficacy studies using an intracranial U87 tumor model showed an increased median survival from 26 days (control cohort) to 38 and 48 days (treated cohorts).. Our present findings establish that NVP-BKM120 inhibits the PI3K signaling pathways, leading to different forms of cell death on the basis of p53 statuses. Further studies are warranted to determine if NVP-BKM120 has potential as a glioma treatment.

Topics: Aminopyridines; Animals; Apoptosis; Blotting, Western; Brain Neoplasms; Cell Cycle; Cell Proliferation; Enzyme Inhibitors; Fluorescent Antibody Technique; Glioma; Humans; Immunoenzyme Techniques; Mice; Mice, Nude; Morpholines; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Real-Time Polymerase Chain Reaction; RNA, Messenger; Tissue Distribution; Tumor Cells, Cultured; Tumor Suppressor Protein p53