Development of patient-derived xenograft models from a spontaneously immortal low-grade meningioma cell line, KCI-MENG1.

Background: There is a paucity of effective therapies for recurrent/aggressive meningiomas. Establishment of improved in vitro and in vivo meningioma models will facilitate development and testing of novel therapeutic approaches.

Methods: A primary meningioma cell line was generated from a patient with an olfactory groove meningioma.

Targeting and killing of glioblastoma with activated T cells armed with bispecific antibodies.

Background: Since most glioblastomas express both wild-type EGFR and EGFRvIII as well as HER2/neu, they are excellent targets for activated T cells (ATC) armed with bispecific antibodies (BiAbs) that target EGFR and HER2.

Methods: ATC were generated from PBMC activated for 14 days with anti-CD3 monoclonal antibody in the presence of interleukin-2 and armed with chemically heteroconjugated anti-CD3 × anti-HER2/neu (HER2Bi) and/or anti-CD3 × anti-EGFR (EGFRBi). HER2Bi- and/or EGFRBi-armed ATC were examined for in vitro cytotoxicity using MTT and 51Cr-release assays against malignant glioma lines (U87MG, U118MG, and U251MG) and primary glioblastoma lines.

In vivo metabolism of tryptophan in meningiomas is mediated by indoleamine 2,3-dioxygenase 1.

Expression and activity of indoleamine 2,3-dioxygenase (IDO), the first and rate-limiting step of the kynurenine pathway of tryptophan catabolism, can enable tumor cells to effectively evade the host's immune response. The potential role of this system was investigated in meningiomas. Surgical specimens from 22 patients with meningiomas were used for cellular, immunological and molecular techniques (immunofluorescence, western blotting, RT-PCR and biochemical assay of enzyme activity) to investigate the expression and activity of IDO.

Tryptophan metabolism in breast cancers: molecular imaging and immunohistochemistry studies.

Introduction: Tryptophan oxidation via the kynurenine pathway is an important mechanism of tumoral immunoresistance. Increased tryptophan metabolism via the serotonin pathway has been linked to malignant progression in breast cancer. In this study, we combined quantitative positron emission tomography (PET) with tumor immunohistochemistry to analyze tryptophan transport and metabolism in breast cancer.

Increased tryptophan transport in epileptogenic dysembryoplastic neuroepithelial tumors.

Dysembryoplastic neuroepithelial tumors (DNTs) are typically hypometabolic but can show increased amino acid uptake on positron emission tomography (PET). To better understand mechanisms of amino acid accumulation in epileptogenic DNTs, we combined quantitative α-[(11)C]methyl-L: -tryptophan (AMT) PET with tumor immunohistochemistry. Standardized uptake values (SUVs) of AMT and glucose were measured in 11 children with temporal lobe DNT.