INTRODUCTION: The risk for diabetes progression varies greatly in individuals with type 2 diabetes mellitus (T2DM). We aimed to study the clinical determinants of diabetes progression in multiethnic Asians with T2DM. MATERIALS AND METHODS: A total of 2057 outpatients with T2DM from a secondary-level Singapore hospital were recruited for the study. Diabetes progression was defined as transition from non-insulin use to requiring sustained insulin treatment or glycated haemoglobin (HbA1c) ≥8.5% when treated with 2 or more oral hypoglycaemic medications. Multivariable logistic regression (LR) was used to study the clinical and biochemical variables that were independently associated with diabetes progression. Forward LR was then used to select variables for a parsimonious model. RESULTS: A total of 940 participants with no insulin use or indication for insulin treatment were analysed. In 3.2 ± 0.4 (mean ± SD) years' follow-up, 163 (17%) participants experienced diabetes progression. Multivariable LR revealed that age at T2DM diagnosis (odds ratio [95% confidence interval], 0.96 [0.94-0.98]), Malay ethnicity (1.94 [1.19-3.19]), baseline HbA1c (2.22 [1.80-2.72]), body mass index (0.96 [0.92-1.00]) and number of oral glucose-lowering medications (1.87 [1.39-2.51]) were independently associated with diabetes progression. Area under receiver operating characteristic curve of the parsimonious model selected by forward LR (age at T2DM diagnosis, Malay ethnicity, HbA1c and number of glucose-lowering medication) was 0.76 (95% CI, 0.72-0.80). CONCLUSION Young age at T2DM diagnosis, high baseline HbA1c and Malay ethnicity are independent determinants of diabetes progression in Asians with T2DM. Further mechanistic studies are needed to elucidate the pathophysiology underpinning progressive loss of glycaemic control in patients with T2DM.

Glioblastoma multiforme (GBM), a highly malignant and heterogeneous brain tumor, contains various types of tumor and non-tumor cells. Whether GBM cells can trans-differentiate into non-neural cell types, including mural cells or endothelial cells (ECs), to support tumor growth and invasion remains controversial. Here we generated two genetic GBM models de novo in immunocompetent mouse brains, mimicking essential pathological and molecular features of human GBMs. Lineage-tracing and transplantation studies demonstrated that, although blood vessels in GBM brains underwent drastic remodeling, evidence of trans-differentiation of GBM cells into vascular cells was barely detected. Intriguingly, GBM cells could promiscuously express markers for mural cells during gliomagenesis. Furthermore, single-cell RNA sequencing showed that patterns of copy number variations (CNVs) of mural cells and ECs were distinct from those of GBM cells, indicating discrete origins of GBM cells and vascular components. Importantly, single-cell CNV analysis of human GBM specimens also suggested that GBM cells and vascular cells are likely separate lineages. Rather than expansion owing to trans-differentiation, vascular cell expanded by proliferation during tumorigenesis. Therefore, cross-lineage trans-differentiation of GBM cells is very unlikely to occur during gliomagenesis. Our findings advance understanding of cell lineage dynamics during gliomagenesis, and have implications for targeted treatment of GBMs.
Mice ; Animals ; Humans ; Glioblastoma/pathology* ; Endothelial Cells/pathology* ; DNA Copy Number Variations ; Brain/metabolism* ; Brain Neoplasms/pathology*