Functional consequence and therapeutic targeting of cryptic ALK fusions in monosomy 7 acute myeloid leukemia.

Acute myeloid leukemia (AML) patients have a wide array of cytogenetic and molecular aberrations, which can influence response to therapy. Monosomy 7 is a rare subset within pediatric AML (prevalence of <2%) that is highly associated with poor outcomes. Fusions involving the anaplastic tyrosine kinase (ALK) gene were exclusively identified in 14.3% of this high-risk cohort, while absent across all other AML. Given the dismal outcomes of monosomy 7, we evaluated the use of crizotinib, an FDA-approved tyrosine kinase inhibitor, used to treat patients with ALK fusions. Our findings suggest that crizotinib may serve as a novel therapy for these patients.

Therapeutic targeting of PRAME with mTCRCAR T cells in acute myeloid leukemia.

Preferentially Expressed Antigen in Melanoma (PRAME), a cancer-testis antigen, provides an ideal target for immunotherapy in acute myeloid leukemia (AML). We have shown expression of PRAME in a significant subset of childhood and adult AML and lack of expression in normal hematopoiesis. Although an intracellular antigen, we developed a novel approach to target PRAME using a chimeric antigen receptor (CAR) construct encoding a targeting domain based on T-cell receptor (TCR) mimic antibodies that target the peptide-HLA complex. We used the antibody sequence from a previously designed TCR mimic (mTCR) antibody, Pr20, that recognizes the PRAME ALY peptide in complex with HLA-A∗02 and verified expression of PRAME in AML cell lines and primary AML blasts. Using the Pr20 antibody sequence, we developed CAR T cells (PRAME mTCRCAR T) to be tested against primary samples from patients with AML and AML cell lines that express the PRAME antigen in the context of HLA-A2 expression. In contrast to appropriate controls, PRAME mTCRCAR T cells demonstrate target-specific and HLA-mediated in vitro activity in OCI-AML2 and THP-1 cell lines, HLA-A2 cell lines expressing the PRAME antigen, and against primary AML patient samples. In vivo cell-derived xenograft models treated with PRAME mTCRCAR T cells demonstrated potent leukemia clearance and improved survival compared with unmodified T-cell controls. Furthermore, the cytolytic activity of PRAME mTCRCAR T cells was enhanced by treating the target cells with interferon gamma, which increases PRAME antigen expression. These results demonstrate the feasibility and efficacy of targeting PRAME with novel PRAME mTCRCAR T cells.

Using Self-Determination Theory to Drive an Evidence-Based Medicine Curriculum for Pediatric Residents: A Mixed Methods Study.

OBJECTIVE: The ability to incorporate evidence-based medicine (EBM) into clinical practice is an Accreditation Council for Graduate Medical Education competency, yet many pediatric residents have limited knowledge in this area. The objective of this study is to describe the effect of an EBM curriculum on resident attitudes and clinical use of EBM. METHODS: We implemented a longitudinal EBM curriculum to review key literature and guidelines and teach EBM principles. In this Institutional Review Board-exempt mixed methods study, we surveyed residents, fellows, and faculty about resident use of EBM at baseline, 6 months, and 12 months after the beginning of the intervention. We conducted point prevalence surveys of faculty about residents' EBM use on rounds. Residents participated in focus groups, which were audio-recorded, transcribed, and coded using conventional content analysis to develop themes. RESULTS: Residents (N = 61 pre- and 70 post-curriculum) reported an increased appreciation for the importance of EBM and comfort generating a search question. Faculty reported that residents cited EBM on rounds, with an average of 2.4 citations/week. Cited evidence reinforced faculty's plans 79% of the time, taught faculty something new 57% of the time, and changed management 21% of the time. Focus groups with 22 trainees yielded 4 themes: 1) increased competence in understanding methodology and evidence quality; 2) greater autonomy in application of EBM; 3) a call for relatedness from faculty role models and a culture that promotes EBM; and 4) several barriers to successful use of EBM. CONCLUSIONS: After implementation of a longitudinal EBM curriculum, trainees described increased use of EBM in clinical practice.