Prognostic value of an eighteen-genes panel in acute myeloid leukemia by analyzing TARGET and TCGA databases.

BACKGROUND: Acute myeloid leukemia (AML) has a poor prognosis, and the current 5-year survival rate is less than 30%. OBJECTIVE: The present study was designed to identify the significant genes closely related to AML prognosis and predict the prognostic value by constructing a risk model based on their expression. METHODS: Using bioinformatics (Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, univariate and multivariate Cox regression analysis, Kaplan-Meier survival analysis, and receiver operating characteristic (ROC) analysis) to identify a prognostic gene signature for AML. Finally, The Cancer Genome Atlas (TCGA) database was used to validate this prognostic signature. RESULTS: Based on univariate and multivariate Cox regression analysis, eighteen prognostic genes were identified, and the gene signature and risk score model were constructed. Multivariate Cox analysis showed that the risk score was an independent prognostic factor [hazard ratio (HR) = 1.122, 95% confidence interval (CI) = 1.067-1.180, P< 0.001]. ROC analysis showed a high predictive value of the risk model with an area under the curve (AUC) of 0.705. CONCLUSIONS: This study evaluated a potential prognostic signature with eighteen genes and constructed a risk model significantly related to the prognosis of AML patients.

Novel gene signature reveals prognostic model in acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is a type of hematological malignancy and has a poor prognosis. In our study, we aimed to construct a prognostic model of ALL by identifying important genes closely related to ALL prognosis. We obtained transcriptome data (RNA-seq) of ALL samples from the GDC TARGET database and identified differentially expressed genes (DEGs) using the "DESeq" package of R software. We used univariate and multivariate cox regression analyses to screen out the prognostic genes of ALL. In our results, the risk score can be used as an independent prognostic factor to predict the prognosis of ALL patients [hazard ratio (HR) = 2.782, 95% CI = 1.903-4.068, p < 0.001]. Risk score in clinical parameters has high diagnostic sensitivity and specificity for predicting overall survival of ALL patients, and the area under curve (AUC) is 0.864 in the receiver operating characteristic (ROC) analysis results. Our study evaluated a potential prognostic signature with six genes and constructed a risk model significantly related to the prognosis of ALL patients. The results of this study can help clinicians to adjust the treatment plan and distinguish patients with good and poor prognosis for targeted treatment.

Identification of a novel GLUT1 inhibitor with in vitro and in vivo anti-tumor activity.

Glucose transporter (GLUT) is a group of membrane proteins which transport extracellular glucoses into cytoplasm, amongst GLUT1 is widely up-regulated in tumor cells. However, no FDA approved GLUT drug has been developed. In this study, we synthesized and identified a novel GLUT1 inhibitor (SMI277) based on in vitro assays and in vivo experiments. Compared with a known GLUT1 inhibitor, SMI277 showed stronger inhibitory activity to glucose uptake, and the inhibition was increased by 40 %. Lactate secretions were decreased by SMI277 in a dose dependent manner. SMI277 was able to inhibit cell proliferations and induce apoptosis of tumor cells. Compared to that of the control group, the tumor growth in mouse model with the administration of 10 mg/kg SMI277 was significantly alleviated and the tumor size was reduced by 58 % on day 21 after inoculation. Interestingly, SMI277 could negatively regulate the expression of GLUT1 protein. Ex vivo experiments showed that SMI277 was capable to enhance CD8+ T cell response. Residues Q283, F379 and E380 were identified as contact residues for GLUT1/SMI277 interactions by mutagenesis based binding affinity measurement. In conclusion, SMI277 appeared to be a good lead compound for drug development with specific GLUT1+ cancer treatment.

Identification of Novel CD39 Inhibitors Based on Virtual Screening and Enzymatic Assays.

The accumulation of adenosine in the tumor microenvironment mediates immunosuppression and promotes tumor growth and proliferation. Intervention of the adenosine pathway is an important direction of antitumor immunity research. CD39 is an important ecto-nucleotidases for adenosine generation, therefore targeting the CD39-adenosine pathway is an emerging immune checkpoint for anticancer treatment. However, currently no CD39 inhibitor has been approved by the U.S. Food and Drug Administration. The development of CD39 drugs is urgent for clinical application. In this study, we combined homology modeling, virtual screening, and in vitro enzymatic activity to characterize the structural features of the CD39 protein and identify a triazinoindole-based compound as a CD39 inhibitor. The identified inhibitor and one of its analogues could effectively prevent the enzymatic activity of CD39 with IC50 values of 27.42 ± 5.52 and 79.24 ± 12.21 µM, respectively. At the same time, the inhibitor significantly inhibited the adenosine monophosphate production in colorectal cancer cell lines (HT29 and MC38) and thereafter prevented cell proliferation. Molecular docking studies, mutagenesis, and microscale thermophoresis indicated that residues such as R85 could be the main contributor in binding triazinoindole compounds. The binding mode can potentially be utilized for hit-to-lead optimization, and the identified inhibitor can be further tested for its anticancer activity in vivo or may serve as a chemical agent to study CD39-related functions.

Discovery of bilirubin as novel P2X7R antagonist with anti-tumor activity.

As a unique ligand gated ion channel in the P2-receptor family, P2X7R is highly expressed in various tumors. The activated P2X7R facilitates tumor growth and metastasis. Hypoxia, inflammation and necrosis in the tumor microenvironment (TME) cause a large amount of adenosine triphosphate (ATP) accumulated in the TME. High concentration of ATP can abnormally activate P2X7R, which induces pore formation and further facilitates the Ca2+ ion influx and non-specific substance intake. Therefore, inhibition of P2X7R activation can be applied as a potential anti-tumor therapy strategy. However, there is currently no FDA approved drugs for this target for anti-tumor treatment. In this study, we identified bilirubin as novel P2X7R antagonist by using structure based virtual screening combined with cell based assays. Molecular docking studies indicated that bilirubin probably interacted with P2X7R by forming hydrogen-π interactions with residues V173, E174 and K311. The compound bilirubin inhibited the P2X7R gated EB intake by cancer cells. Meanwhile, bilirubin was capable to inhibit the cell proliferation and migration of P2X7R expressed HT29 cells. The phosphorylation of mTOR, STAT3 and GSK3ß were significantly decreased when bilirubin was present. Finally, in vivo experiment exhibited the anti-tumor effect of bilirubin in the MC38 bearing mice model, but did not show tissue damage in different organs. In conclusion, bilirubin was identified as a novel P2X7R antagonist and it may have potential for anti-cancer treatment, although various functions of the molecule should be considered.

Identification of novel inhibitors of GLUT1 by virtual screening and cell-based assays.

In order to fuel the uncontrolled cell proliferation and division, tumor cells reprogram the energy metabolism to Warburg effect, where glucose is preferably converted by glycolysis even in the presence of oxygen. However, the high energetic demand of tumor cells require upregulating the expression of glucose transporters, notably GLUT1, which substantially increases glucose uptake into cytoplasm. GLUT1 is overexpressed in a variety of tumor cells and is likely to be a potential drug target in the treatment of pan-cancers. Although many small molecules were reported to inhibit the glucose uptake function by various measurements, several shortcomings such as weak binding affinity, low specificity of the known inhibitors demand the identification of alternative inhibitors with novel scaffolds. In this study, we performed a virtual screening campaign by docking each compound from Chemdiv database to the glucose binding pocket based on the crystal structure of GLUT1 (PDB ID 4PYP) and four small molecules with novel scaffolds were identified to inhibit the glucose uptake of cancer cells at the sub-micromole level. The identified compounds may serve as starting points for the development of anti-cancer drugs via the manipulation of the energy metabolism.