Spheroid Drug Sensitivity Screening in Glioma Stem Cell Lines.

In vitro drug sensitivity screens are important tools in the discovery of anti-cancer drug combination therapies. Typically, these in vitro drug screens are performed on cells grown in a monolayer. However, these two-dimensional (2D) models are considered less accurate compared to three-dimensional (3D) spheroid cell models; this is especially true for glioma stem cell lines. Cells grown in spheres activate different signaling pathways and are considered more representative of in vivo models than monolayer cell lines. This protocol describes a method for in vitro drug screening of spheroid lines; mouse and human glioma stem cell lines are used as an example. This protocol describes a 3D spheroid drug sensitivity and synergy assay that can be used to determine if a drug or drug combination induces cell death and if two drugs synergize. Glioma stem cell lines are modified to express RFP. Cells are plated in low attachment round well bottom 96 plates, and spheres are allowed to form overnight. Drugs are added, and the growth is monitored by measuring the RFP signal over time using the Incucyte live imaging system, a fluorescence microscope embedded in the tissue culture incubator. Half maximal inhibitory concentration (IC50), median lethal dose (LD50), and synergy score are subsequently calculated to evaluate sensitivities to drugs alone or in combination. The three-dimensional nature of this assay provides a more accurate reflection of tumor growth, behavior, and drug sensitivities in vivo, thus forming the basis for further preclinical investigation.

Knowledge and Self-Efficacy Assessment of Residents and Fellows Following Palliative Care Unit Rotation: A Pilot Study.

BACKGROUND: In Germany, some units of specialized palliative care (SPC) offer a 6- to 12-month rotation for resident physicians (RPs) and fellows from different specialties. OBJECTIVE: This pilot study aimed to evaluate feasibility of assessing palliative care knowledge (PCK) and palliative care self-efficacy (PCSE) using a paper-based questionnaire. METHODS: Palliative care knowledge and PCSE were assessed by introducing a score, followed by a descriptive analysis (determination of frequency, mean, median, and range) using nonparametric tests (χ2 test, Mann-Whitney U test). RESULTS: We assessed 17 RPs following SPC rotation and 16 board-certified specialists (BCSs) who had no experience in SPC from 3 German comprehensive cancer centers. Resident physicians were predominantly enrolled in residency programs of hematology and oncology (n = 6), anesthesiology (n = 6), and psychosomatic medicine (n = 3). Resident physicians rotated between year 1 and 8 of residency. Fifteen RPs (88%) had elected this rotation and 72% preferred 12-month duration. The total PCK score of PCK was 27 (RPs) and 24 (BCSs; P = .002). Mean PCSE scores were 46 (RPs) and 39 (BCSs; P = .016). Of 71% of RPs, only 27% of BCSs knew how support of hospice service was initiated ( P = .004). Participants rated the items as comprehensible (n = 24; 73%), relevant (n = 25; 76%) and the questionnaire as adequately long (n = 23; 70%). CONCLUSION: An improved PCK and PCSE were observed in physicians who rotated through an SPC unit; this resulted in an increased tangibility of local palliative care and hospice services. The questionnaire was comprehensible, relevant in terms of content, and adequate in length for a prospective multicenter survey.

Combinatorial therapy with tamoxifen and trifluoperazine effectively inhibits malignant peripheral nerve sheath tumor growth by targeting complementary signaling cascades.

Chemotherapeutic agents effective against malignant peripheral nerve sheath tumors (MPNSTs) are urgently needed. We recently found that tamoxifen potently impedes xenograft growth. In vitro, tamoxifen inhibits MPNST proliferation and survival in an estrogen receptor-independent manner; these effects are phenocopied by the calmodulin inhibitor trifluoperazine. The present study was performed to establish the mechanism of action of tamoxifen in vivo and optimize its therapeutic effectiveness. To determine if tamoxifen has estrogen receptor-dependent effects in vivo, we grafted MPNST cells in castrated and ovariectomized mice; xenograft growth was unaffected by reductions in sex hormones. To establish whether tamoxifen and trifluoperazine additively or synergistically impede MPNST growth, mice xenografted with neurofibromatosis type 1-associated or sporadic MPNST cells were treated with tamoxifen, trifluoperazine, or both drugs for 30 days. Both monotherapies inhibited graft growth by 50%, whereas combinatorial treatment maximally reduced graft mass by 90% and enhanced decreases in proliferation and survival. Kinomic analyses showed that tamoxifen and trifluoperazine have both shared and distinct targets in MPNSTs. In addition, trifluoperazine prevented tamoxifen-induced increases in serum/glucocorticoid regulated kinase 1, a protein linked to tamoxifen resistance. These findings suggest that combinatorial therapy with tamoxifen and trifluoperazine is effective against MPNSTs because these agents target complementary pathways that are essential for MPNST pathogenesis.