The diagnosis of childhood haematological malignancy with first bony presentation to the ER was challenging, with a high prevalence of 71.4% undiagnosed cases at first visit. We highlight the common misdiagnoses because failure to correctly diagnose could delay timely institution of treatment. Trauma or normal investigations do not exclude an underlying haematological malignancy. This rare diagnosis in the ER should always be considered when challenged with recurrent bony complaints.
Diffuse invasion is the primary cause of treatment failure of glioblastoma (GBM). Previous studies on GBM invasionhave long been forced to use the resected tumor mass cells. Here, a strategy to reliably isolate matching pairs of invasive (GBM INV ) and tumor core (GBM TC ) cells from the brains of 6 highly invasive patient-derived orthotopic models is described. Direct comparison of these GBM INV and GBM TC cells reveals a significantly elevated invasion capacity in GBM INV cells, detects 23/768 miRNAs over-expressed in the GBM INV cells (miRNA INV ) and 22/768 in the GBM TC cells (miRNA TC ), respectively. Silencing the top 3 miRNAs INV (miR-126, miR-369-5p, miR-487b) successfully blocks invasion of GBM INV cells in vitro and in mouse brains. Integrated analysis with mRNA expression identifies miRNA INV target genes and discovers KCNA1 as the sole common computational target gene of which 3 inhibitors significantly suppress invasion in vitro. Furthermore, in vivo treatment with 4-aminopyridine (4-AP) effectively eliminates GBM invasion and significantly prolongs animal survival times (P = 0.035). The results highlight the power of spatial dissection of functionally accurate GBM INV and GBM TC cells in identifying novel drivers of GBM invasion and provide strong rationale to support the use of biologically accurate starting materials in understanding cancer invasion and metastasis.
Introduction
The importance of fatty acid oxidation (FAO) in the bioenergetics of glioblastoma (GBM) is being realized. Etomoxir (ETO), a carnitine palmitoyltransferase 1 (CPT1) inhibitor exerts cytotoxic effects in GBM, which involve interrupting the FAO pathway. We hypothesized that FAO inhibition could affect the outcomes of current standard temozolomide (TMZ) chemotherapy against GBM.
Methods
The FAO-related gene expression was compared between GBM and the tumor-free cortex. Using four different GBM tumorspheres (TSs), the effects of ETO and/or TMZ was analyzed on cell viability, tricarboxylate (TCA) cycle intermediates and adenosine triphosphate (ATP) production to assess metabolic changes. Alterations in tumor stemness, invasiveness, and associated transcriptional changes were also measured. Mouse orthotopic xenograft model was used to elucidate the combinatory effect of TMZ and ETO.
Results
GBM tissues exhibited overexpression of FAO-related genes, especially CPT1A, compared to the tumor-free cortex. The combined use of ETO and TMZ further inhibited TCA cycle and ATP production than single uses. This combination treatment showed superior suppression effects compared to treatment with individual agents on the viability, stemness, and invasiveness of GBM TSs, as well as better downregulation of FAO-related gene expression. The results of in vivo study showed prolonged survival outcomes in the combination treatment group.
Conclusion
ETO, an FAO inhibitor, causes a lethal energy reduction in the GBM TSs. When used in combination with TMZ, ETO effectively reduces GBM cell stemness and invasiveness and further improves survival. These results suggest a potential novel treatment option for GBM.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.