Evaluation of the Association Between Congenital Cytomegalovirus Infection and Pediatric Acute Lymphoblastic Leukemia.

Importance: Acute lymphoblastic leukemia (ALL) is the most common form of pediatric cancer, and a leading cause of death in children. Understanding the causes of pediatric ALL is necessary to enable early detection and prevention; congenital cytomegalovirus (cCMV) has recently been identified as a potential moderate-to-strong factor associated with risk for ALL. Objective: To compare the prevalence of cCMV infection between ALL cases and matched controls. Design, Setting, and Participants: In this population-based case-control study of ALL cases and matched controls, cases consisted of children aged 0 to 14 years between 1987 and 2014 with an ALL diagnosis identified through the Michigan Cancer Surveillance Program and born in Michigan on or after October 1, 1987. Cancer-free controls were identified by the Michigan BioTrust for Health and matched on age, sex, and mother's race and ethnicity. Data were analyzed from November to May 2022. Exposures: cCMV infection measured by quantitative polymerase chain reaction in newborn dried blood spots. Main Outcomes and Measures: ALL diagnosed in children aged 0 to 14 years. Results: A total of 1189 ALL cases and 4756 matched controls were included in the study. Bloodspots were collected from participants at birth, and 3425 (57.6%) participants were male. cCMV was detected in 6 ALL cases (0.5%) and 21 controls (0.4%). There was no difference in the odds of cCMV infection comparing ALL cases with controls (odds ratio, 1.30; 95% CI, 0.52-3.24). Immunophenotype was available for 536 cases (45.1%) and cytogenetic data for 127 (27%). When stratified by subtype characteristics, hyperdiploid ALL (74 cases) was associated with 6.26 times greater odds of cCMV infection compared with unmatched controls (95% CI, 1.44-27.19). Conclusions and Relevance: In this case-control study of cCMV and pediatric ALL, cCMV was associated with increased risk of hyperdiploid ALL. These findings encourage continued research.

Genomic Status of MET Potentiates Sensitivity to MET and MEK Inhibition in NF1-Related Malignant Peripheral Nerve Sheath Tumors.

Malignant peripheral nerve sheath tumors (MPNST) are highly resistant sarcomas that occur in up to 13% of individuals with neurofibromatosis type I (NF1). Genomic analysis of longitudinally collected tumor samples in a case of MPNST disease progression revealed early hemizygous microdeletions in NF1 and TP53, with progressive amplifications of MET, HGF, and EGFR To examine the role of MET in MPNST progression, we developed mice with enhanced MET expression and Nf1 ablation (Nf1fl/ko;lox-stop-loxMETtg/+;Plp-creERTtg/+ ; referred to as NF1-MET). NF1-MET mice express a robust MPNST phenotype in the absence of additional mutations. A comparison of NF1-MET MPNSTs with MPNSTs derived from Nf1ko/+;p53R172H;Plp-creERTtg/+ (NF1-P53) and Nf1ko/+;Plp-creERTtg/+ (NF1) mice revealed unique Met, Ras, and PI3K signaling patterns. NF1-MET MPNSTs were uniformly sensitive to the highly selective MET inhibitor, capmatinib, whereas a heterogeneous response to MET inhibition was observed in NF1-P53 and NF1 MPNSTs. Combination therapy of capmatinib and the MEK inhibitor trametinib resulted in reduced response variability, enhanced suppression of tumor growth, and suppressed RAS/ERK and PI3K/AKT signaling. These results highlight the influence of concurrent genomic alterations on RAS effector signaling and therapy response to tyrosine kinase inhibitors. Moreover, these findings expand our current understanding of the role of MET signaling in MPNST progression and identify a potential therapeutic niche for NF1-related MPNSTs.Significance: Longitudinal genomic analysis reveals a positive selection for MET and HGF copy number gain early in malignant peripheral nerve sheath tumor progression. Cancer Res; 78(13); 3672-87. ©2018 AACR.

Wnt Signaling in Ewing Sarcoma, Osteosarcoma, and Malignant Peripheral Nerve Sheath Tumors.

PURPOSE OF REVIEW: Wnt signaling plays a central role in development and homeostasis, and its dysregulation is a common event in many types of human cancer. Here we explore in detail the contributions of Wnt signaling to the initiation and maintenance of three types of saroma: Ewing sarcoma, osteosarcoma, and malignant peripheral nerve sheath tumors. This review provides an overview of the Wnt signaling pathway and explores in detail the current knowledge about its role in the initiation or maintenance of three tumor types: Ewing sarcoma, osteosarcoma, and malignant peripheral nerve sheath tumors. RECENT FINDINGS: Recent work has assessed the role(s) of Wnt signaling within these cell types. This review provides an overview of the mechanistic insights that have been gained from a number of recent studies to set the foundation for potential therapeutic applications. Wnt signaling has emerged as a potentially critical pathway in maintaining the growth of these types of tumors. Given the fact that many new inhibitors of the pathway have recently or will soon enter Phase 1 clinical trials, it is likely that assessment of their activity in these tumor types will occur in human patients.