No in vitro method for culturing Primary Leukemia Cells exists. Thus, study of Primary Leukemia biology requires immunodeficient mouse models, which is costly and time consuming. Identifying a method to grow and maintain Primary Leukemia Cells in vitro would allow biological and molecular assays to facilitate bench to bedside translation.

Rhabdoid tumor of the kidney (RTK) is a rare but aggressive cancer that occurs in infancy and early childhood.[1] Current treatment protocols for RTK included a combination of surgery, radiation therapy, and chemotherapy, however the prognosis remains poor with a 5-year survival between 20-25%.[1] Therefore, the need to develop therapeutic strategies to treat RTK is still greatly unmet. High dependence on glycolysis by cancer cells, known as the Warburg effect [2], demonstrates a weakness that can be harnessed to target cancer cells and provides rationale for exploring antiglycolytic approaches for targeting cancer cells. Glyceraldehye-3-phosphate dehydrogenase (GAPDH) is an essential enzyme within the glycolysis pathway (Figure 1) making GAPDH a potential therapeutic target for inhibiting tumor growth and progression [3]. Aspergillus oryzae is a probiotic fungus that is used in the production of Japanese fermented food, including soybean paste and soy sauce. Heptelidic acid (HA) is a sesquiterpene lactone derived from A. oryzae and has recently been shown to exert antitumor effects against multiple cancers including pancreatic and extraintestinal melanomas. [4,5] HA is a specific and irreversible inhibitor of GAPDH.[6] Its GAPDH inhibition activity is shown to contribute to its antitumor effects. [4,5]. The purpose of this study is to assess the therapeutic potential of HA on RTK. This study gives the first evidence that HA shows cytotoxicity in RTK and provides rationale to ultimately develop a therapy using HA for RTK.

Compound 10357 is an amiloride derivative with potential promise as an adjunct to current chemotherapeutics. This study investigates the therapeutic efficacy of Compound 10357 in B-Cell Acute Lymphoblastic Leukemia (B-ALL).

B-cell acute lymphoblastic leukemia (B-ALL) is the most common type of cancer found in children. Although the overall survival rates are now >80%, 15%-20% of pediatric patients relapse, with survival rates subsequently dropping to 5%-10%. Cmpd10357, 3-amino-5-arylamino-6-chloro-N- (diaminomethylene) pyrazine-2-carboximide, is a highly potent, cell-permeant compound recently shown to have cytotoxic effects on solid tumors, including human breast cancer and high-grade gliomas, independent of their proliferative status. Cmpd10357 demonstrated concentration-dependent cytotoxicity in two human B-ALL cell lines, JM1 and Reh, at half-maximal inhibitory concentrations (IC₅₀) of 3.2 and 3.3 μM, respectively. Cmpd10357, at a dose of 5 mg/kg, significantly prolonged survival in our B-ALL xenograft mouse model, with a median survival time of 49.0 days compared with 45.5 days in the control group (p < 0.05). The cytotoxicity of Cmpd10357 demonstrated caspase-independent, nonapoptotic cancer cell demise associated with the nuclear translocation of apoptosis-inducing factor (AIF). The cytotoxicity of Cmpd10357 in B-ALL cells was inhibited by Necrostatin-1 but not by Necrosulfonamide. These studies suggest that an AIF-mediated, caspase-independent necrosis mechanism of Cmpd10357 in B-ALL could be used in combination with traditional apoptotic chemotherapeutic agents.

In leukemia, a distinct subpopulation of cancer-initiating cells called leukemia stem cells (LSCs) is believed to drive population expansion and tumor growth. Failing to eliminate LSCs may result in disease relapse regardless of the amount of non-LSCs destroyed. The first step in targeting and eliminating LSCs is to identify and characterize them. Acute precursor B lymphoblastic leukemia (B-ALL) cells derived from patients were incubated with fluorescent glucose analog 2-(N-(7-Nitrobenz-2-oxa-1, 3-diazol-4-yl) Amino)-2-Deoxyglucose (NBDG) and sorted based on NBDG uptake. Cell subpopulations defined by glucose uptake were then serially transplanted into mice and evaluated for leukemia initiating capacity. Gene expression profiles of these cells were characterized using RNA-Sequencing (RNA-Seq). A distinct population of NBDG-low cells was identified in patient B-ALL samples. These cells are a small population (1.92% of the entire leukemia population), have lower HLA expression, and are smaller in size (4.0 to 7.0 μm) than the rest of the leukemia population. All mice transplanted with NBDG-low cells developed leukemia between 5 and 14 weeks, while those transplanted with NBDG-high cells did not develop leukemia (p ≤ 0.0001-0.002). Serial transplantation of the NBDG-low mouse model resulted in successful leukemia development. NBDG-medium (NBDG-med) populations also developed leukemia. Interestingly, comprehensive molecular characterization of NBDG-low and NBDG-med cells from patient-derived xenograft (PDX) models using RNA-Seq revealed a distinct profile of 2,162 differentially-expressed transcripts (DETs) (p<0.05) with 70.6% down-regulated in NBDG-low cells. Hierarchical clustering of DETs showed distinct segregation of NBDG-low from NBDG-med and NBDG-high groups with marked transcription expression alterations in the NBDG-low group consistent with cancer survival. In conclusion, A unique subpopulation of cells with low glucose uptake (NBDG-low) in B-ALL was discovered. These cells, despite their quiescence characteristics, once transplanted in mice, showed potent leukemia initiating capacity. Although NBDG-med cells also initiated leukemia, gene expression profiling revealed a distinct signature that clearly distinguishes NBDG-low cells from NBDG-med and the rest of the leukemia populations. These results suggest that NBDG-low cells may represent quiescent LSCs. These cells can be activated in the appropriate environment in vivo, showing leukemia initiating capacity. Our study provides insight into the biologic mechanisms of B-ALL initiation and survival.