Comparison of the loci associated with HbA1c and blood glucose levels identified by a genome-wide association study in the Japanese population.

Aims: Hemoglobin A1c (HbA1c) levels are widely employed to diagnose diabetes. However, estimates of the heritability of HbA1c and glucose levels are different. Therefore, we explored HbA1c- and blood glucose-associated loci in a non-diabetic Japanese population. Methods: We conducted a two-stage genome-wide association study (GWAS) on variants associated with HbA1c and blood glucose levels in a Japanese population. In the initial stage, data of 4911 participants of the Japan Multi-Institutional Collaborative Cohort (J-MICC) were subjected to discovery analysis. In the second stage, two datasets from the Tohoku Medical Megabank project, with 8175 and 40,519 participants, were used for the replication study. Association of the imputed variants with HbA1c and blood glucose levels was determined via linear regression analyses adjusted for age, sex, body mass index (BMI), smoking, and genetic principal components (PC1-PC10). Moreover, we performed a BMI-stratified GWAS on HbA1c levels in the J-MICC. The discovery analysis and BMI-stratified GWAS results were validated with re-analyses of normalized HbA1c levels adjusted for site in addition to the above, and blood glucose adjusted for fasting time as an additional covariate. Results: Genetic variants associated with HbA1c levels were identified in KCNQ1 and TMC6. None of the genetic variants associated with blood glucose levels in the discovery analysis were replicated. Association of rs2299620 in KCNQ1 with HbA1c levels showed heterogeneity between individuals with BMI ≥ 25 kg/m2 and BMI < 25 kg/m2. Conclusions: The variant rs2299620 in KCNQ1 might affect HbA1c levels differentially based on BMI grouping in the Japanese population. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-023-00618-0.

Fibroblast growth factor receptor 3 overexpression mediates ALK inhibitor resistance in ALK-rearranged non-small cell lung cancer.

The rearrangement of anaplastic lymphoma kinase (ALK) occurs in 3%-5% of patients with non-small cell lung cancer (NSCLC) and confers sensitivity to ALK-tyrosine kinase inhibitors (TKIs). For the treatment of patients with ALK-rearranged NSCLC, various additional ALK-TKIs have been developed. Ceritinib is a second-generation ALK-TKI and has shown great efficacy in the treatment of patients with both newly diagnosed and crizotinib (a first-generation ALK-TKI)-refractory ALK-rearranged NSCLC. However, tumors can also develop ceritinib resistance. This may result from secondary ALK mutations, but other mechanisms responsible for this have not been fully elucidated. In this study, we explored the mechanisms of ceritinib resistance by establishing ceritinib-resistant, echinoderm microtubule-associated protein-like 4 (EML4)-ALK-positive H3122 cells and ceritinib-resistant patient-derived cells. We identified a mechanism of ceritinib resistance induced by bypass signals that is mediated by the overexpression and activation of fibroblast growth factor receptor 3 (FGFR3). FGFR3 knockdown by small hairpin RNA or treatment with FGFR inhibitors was found to resensitize the resistant cells to ceritinib in vitro and in vivo. FGFR ligands from either human serum or fetal bovine serum were able to activate FGFR3 and induce ceritinib resistance. A detailed analysis of ceritinib-resistant patient-derived specimens confirmed that tyrosine-protein kinase Met (cMET) amplification induces ceritinib resistance. Amplified cMET counteractivated EGFR and/or Her3 and induced ceritinib resistance. These results reveal multiple ceritinib resistance mechanisms and suggest that ceritinib resistance might be overcome by identifying precise resistance mechanisms.

Exploitation of Elevated Extracellular ATP to Specifically Direct Antibody to Tumor Microenvironment.

The extracellular adenosine triphosphate (ATP) concentration is highly elevated in the tumor microenvironment (TME) and remains tightly regulated in normal tissues. Using phage display technology, we establish a method to identify an antibody that can bind to an antigen only in the presence of ATP. Crystallography analysis reveals that ATP bound in between the antibody-antigen interface serves as a switch for antigen binding. In a transgenic mouse model overexpressing the antigen systemically, the ATP switch antibody binds to the antigen in tumors with minimal binding in normal tissues and plasma and inhibits tumor growth. Thus, we demonstrate that elevated extracellular ATP concentration can be exploited to specifically target the TME, giving therapeutic antibodies the ability to overcome on-target off-tumor toxicity.

Prediction of ALK mutations mediating ALK-TKIs resistance and drug re-purposing to overcome the resistance.

BACKGROUND: Alectinib has shown a greater efficacy to ALK-rearranged non-small-cell lung cancers in first-line setting; however, most patients relapse due to acquired resistance, such as secondary mutations in ALK including I1171N and G1202R. Although ceritinib or lorlatinib was shown to be effective to these resistant mutants, further resistance often emerges due to ALK-compound mutations in relapse patients following the use of ceritinib or lorlatinib. However, the drug for overcoming resistance has not been established yet. METHODS: We established lorlatinib-resistant cells harboring ALK-I1171N or -G1202R compound mutations by performing ENU mutagenesis screening or using an in vivo mouse model. We performed drug screening to overcome the lorlatinib-resistant ALK-compound mutations. To evaluate these resistances in silico, we developed a modified computational molecular dynamic simulation (MP-CAFEE). FINDINGS: We identified 14 lorlatinib-resistant ALK-compound mutants, including several mutants that were recently discovered in lorlatinib-resistant patients. Some of these compound mutants were found to be sensitive to early generation ALK-TKIs and several BCR-ABL inhibitors. Using our original computational simulation, we succeeded in demonstrating a clear linear correlation between binding free energy and in vitro experimental IC50 value of several ALK-TKIs to single- or compound-mutated EML4-ALK expressing Ba/F3 cells and in recapitulating the tendency of the binding affinity reduction by double mutations found in this study. Computational simulation revealed that ALK-L1256F single mutant conferred resistance to lorlatinib but increased the sensitivity to alectinib. INTERPRETATION: We discovered lorlatinib-resistant multiple ALK-compound mutations and an L1256F single mutation as well as the potential therapeutic strategies for these ALK mutations. Our original computational simulation to calculate the binding affinity may be applicable for predicting resistant mutations and for overcoming drug resistance in silico. FUND: This work was mainly supported by MEXT/JSPS KAKENHI Grants and AMED Grants.

P-glycoprotein Mediates Ceritinib Resistance in Anaplastic Lymphoma Kinase-rearranged Non-small Cell Lung Cancer.

The anaplastic lymphoma kinase (ALK) fusion oncogene is observed in 3%-5% of non-small cell lung cancer (NSCLC). Crizotinib and ceritinib, a next-generation ALK tyrosine kinase inhibitor (TKI) active against crizotinib-refractory patients, are clinically available for the treatment of ALK-rearranged NSCLC patients, and multiple next-generation ALK-TKIs are currently under clinical evaluation. These ALK-TKIs exhibit robust clinical activity in ALK-rearranged NSCLC patients; however, the emergence of ALK-TKI resistance restricts the therapeutic effect. To date, various secondary mutations or bypass pathway activation-mediated resistance have been identified, but large parts of the resistance mechanism are yet to be identified. Here, we report the discovery of p-glycoprotein (P-gp/ABCB1) overexpression as a ceritinib resistance mechanism in ALK-rearranged NSCLC patients. P-gp exported ceritinib and its overexpression conferred ceritinib and crizotinib resistance, but not to PF-06463922 or alectinib, which are next-generation ALK inhibitors. Knockdown of ABCB1 or P-gp inhibitors sensitizes the patient-derived cancer cells to ceritinib, in vitro and in vivo. P-gp overexpression was identified in three out of 11 cases with in ALK-rearranged crizotinib or ceritinib resistant NSCLC patients. Our study suggests that alectinib, PF-06463922, or P-gp inhibitor with ceritinib could overcome the ceritinib or crizotinib resistance mediated by P-gp overexpression.