NUC-7738 regulates ß-catenin signalling resulting in reduced proliferation and self-renewal of AML cells.

Acute myeloid leukemia (AML) stem cells are required for the initiation and maintenance of the disease. Activation of the Wnt/ß-catenin pathway is required for the survival and development of AML leukaemia stem cells (LSCs) and therefore, targeting ß-catenin is a potential therapeutic strategy. NUC-7738, a phosphoramidate transformation of 3'-deoxyadenosine (3'-dA) monophosphate, is specifically designed to generate the active anti-cancer metabolite 3'-deoxyadenosine triphosphate (3'-dATP) intracellularly, bypassing key limitations of breakdown, transport, and activation. NUC-7738 is currently in a Phase I/II clinical study for the treatment of patients with advanced solid tumors. Protein expression and immunophenotypic profiling revealed that NUC-7738 caused apoptosis in AML cell lines through reducing PI3K-p110α, phosphorylated Akt (Ser473) and phosphorylated GSK3ß (Ser9) resulting in reduced ß-catenin, c-Myc and CD44 expression. NUC-7738 reduced ß-catenin nuclear expression in AML cells. NUC-7738 also decreased the percentage of CD34+ CD38- CD123+ (LSC-like cells) from 81% to 47% and reduced the total number and size of leukemic colonies. These results indicate that therapeutic targeting of the PI3K/Akt/GSK3ß axis can inhibit ß-catenin signalling, resulting in reduced clonogenicity and eventual apoptosis of AML cells.

A Comparison of Methods for Studying the Tumor Microenvironment's Spatial Heterogeneity in Digital Pathology Specimens.

BACKGROUND: The tumor microenvironment is highly heterogeneous, and it is understood to affect tumor progression and patient outcome. A number of studies have reported the prognostic significance of tumor-infiltrating lymphocytes and tumor budding in colorectal cancer (CRC). However, the significance of the intratumoral heterogeneity present in the spatial distribution of these features within the tumor immune microenvironment (TIME) has not been previously reported. Evaluating this intratumoral heterogeneity may aid the understanding of the TIME's effect on patient prognosis as well as identify novel aggressive phenotypes which can be further investigated as potential targets for new treatment. METHODS: In this study, we propose and apply two spatial statistical methodologies for the evaluation of the intratumor heterogeneity present in the distribution of CD3 + and CD8 + lymphocytes and tumor buds (TB) in 232 Stage II CRC cases. Getis-Ord hotspot analysis was applied to quantify the cold and hotspots, defined as regions with a significantly low or high number of each feature of interest, respectively. A novel spatial heatmap methodology for the quantification of the cold and hotspots of each feature of interest, which took into account both the interpatient heterogeneity and the intratumor heterogeneity, was further developed. RESULTS: Resultant data from each analysis, characterizing the spatial intratumor heterogeneity of lymphocytes and TBs were used for the development of two new highly prognostic risk models. CONCLUSIONS: Our results highlight the value of applying spatial statistics for the assessment of the intratumor heterogeneity. Both Getis-Ord hotspot and our proposed spatial heatmap analysis are broadly applicable across other tissue types as well as other features of interest. AVAILABILITY: The code underpinning this publication can be accessed at https://doi.org/10.17630/c2306fe9-66e2-4442-ad89-f986220053e2.