Modulation of anti-cancer drug sensitivity through the regulation of mitochondrial activity by adenylate kinase 4

Background: Adenylate kinase is a key enzyme in the high-energy phosphoryl transfer reaction in living cells. An isoform of this enzyme, adenylate kinase 4 (AK4), is localized in the mitochondrial matrix and is believed to be involved in stress, drug resistance, malignant transformation in cancer, and ATP regulation. However, the molecular basis for the AK4 functions remained to be determined. Methods: HeLa cells were transiently transfected with an AK4 small interfering RNA (siRNA), an AK4 short hairpin RNA (shRNA) plasmid, a control shRNA plasmid, an AK4 expression vector, and a control expression vector to examine the effect of the AK4 expression on cell proliferation, sensitivity to anti-cancer drug, metabolome, gene expression, and mitochondrial activity. Results: AK4 knockdown cells treated with short hairpin RNA increased ATP production and showed greater sensitivity to hypoxia and anti-cancer drug, cis-diamminedichloro-platinum (II) (CDDP). Subcutaneous grafting AK4 knockdown cells into nude mice revealed that the grafted cells exhibited both slower proliferation and reduced the tumor sizes in response to CDDP. AK4 knockdown cell showed a increased oxygen consumption rate with FCCP treatment, while AK4 overexpression lowered it. Metabolome analysis showed the increased levels of the tricarboxylic acid cycle intermediates, fumarate and malate in AK4 knockdown cells, while AK4 overexpression lowered them. Electron microscopy detected the increased mitochondrial numbers in AK4 knockdown cells. Microarray analysis detected the increased gene expression of two key enzymes in TCA cycle, succinate dehydrogenase A (SDHA) and oxoglutarate dehydrogenease L (OGDHL), which are components of SDH complex and OGDH complex, supporting the metabolomic results. Conclusions: We found that AK4 was involved in hypoxia tolerance, resistance to anti-tumor drug, and the regulation of mitochondrial activity. These findings provide a new potential target for efficient anticancer therapies by controlling AK4 expression

Anionic ordering in Pb₂Ti₄O₉F₂ revisited by nuclear magnetic resonance and density functional theory

複合アニオン材料の構造決定における実験と計算の融合的アプローチ. 京都大学プレスリリース. 2022-10-31.A combination of 19F magic angle spinning (MAS) nuclear magnetic resonance (NMR) and density functional theory (DFT) were used to study the ordering of F atoms in Pb₂Ti₄O₉F₂. This analysis revealed that F atoms predominantly occupy two of the six available inequivalent sites in a ratio of 73 : 27. DFT-based calculations explained the preference of F occupation on these sites and quantitatively reproduced the experimental occupation ratio, independent of the choice of functional. We concluded that the Pb atom's 6s2 lone pair may play a role (∼0.1 eV per f.u.) in determining the majority and minority F occupation sites with partial density of states and crystal orbital Hamiltonian population analyses applied to the DFT wave functions

Anionic ordering in Pb₂Ti₄O₉F₂ revisited by nuclear magnetic resonance and density functional theory

複合アニオン材料の構造決定における実験と計算の融合的アプローチ. 京都大学プレスリリース. 2022-10-31.A combination of 19F magic angle spinning (MAS) nuclear magnetic resonance (NMR) and density functional theory (DFT) were used to study the ordering of F atoms in Pb₂Ti₄O₉F₂. This analysis revealed that F atoms predominantly occupy two of the six available inequivalent sites in a ratio of 73 : 27. DFT-based calculations explained the preference of F occupation on these sites and quantitatively reproduced the experimental occupation ratio, independent of the choice of functional. We concluded that the Pb atom's 6s2 lone pair may play a role (∼0.1 eV per f.u.) in determining the majority and minority F occupation sites with partial density of states and crystal orbital Hamiltonian population analyses applied to the DFT wave functions

発症早期ALS患者に対する超高用量メチルコバラミンの有効性・安全性について : ランダム化比較試験

Importance: Post hoc analysis in a phase 2/3 trial indicated ultra-high dose methylcobalamin slowed decline of the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) total score at week 16 as well as at week 182, without increase of adverse events, in patients with amyotrophic lateral sclerosis (ALS) who were enrolled within 1 year from onset. Objective: To validate the efficacy and safety of ultra-high dose methylcobalamin for patients with ALS enrolled within 1 year of onset. Design: A multicenter, placebo-controlled, double-blind, randomized phase 3 trial with 12-week observation and 16-week randomized period, conducted from October 2017 to September 2019. Setting: Twenty-five neurology centers in Japan. Participants: Patients with ALS diagnosed within 1 year of onset by the updated Awaji criteria were initially enrolled. Of those, patients fulfilling the following criteria after 12-week observation were eligible for randomization: 1- or 2-point decrease in ALSFRS-R total score, a percent forced vital capacity over 60%, no history of noninvasive respiratory support and tracheostomy, and being ambulant. The target number was 64 in both methylcobalamin and placebo groups. Of 203 patients enrolled in the observation, 130 patients (age, 61.0 ± 11.7 years; female, 56) met the criteria and were randomly assigned through an electronic web-response system to methylcobalamin or placebo (65 for each). Of these, 129 patients were eligible for the full analysis set, and 126 completed the double-blind stage. Interventions: Intramuscular injection of methylcobalamin 50 mg or placebo twice weekly for 16 weeks. Main outcomes and measures: The primary endpoint was change in ALSFRS-R total score from baseline to week 16 in the full analysis set. Results: The least-squares mean difference in ALSFRS-R total score at week 16 of the randomized period was 1.97 points greater with methylcobalamin than placebo (−2.66 versus −4.63; 95% CI, 0.44–3.50; P = 0.012). The incidence of adverse events was similar between the two groups. Conclusions and relevance: Ultra-high dose methylcobalamin was efficacious in slowing functional decline and safe in the 16-week treatment period in ALS patients in the early stage and with moderate progression rate. Trial registration: UMIN-CTR Identifier: UMIN000029588 (umin.ac.jp/ctr); ClinicalTrials.gov Identifier: NCT03548311 (clinicaltrials.gov

Monitoring of CA19-9 and SPan-1 can facilitate the earlier confirmation of progressing pancreatic cancer during chemotherapy

Background: Measurement of objective response to chemotherapy using imaging modalities is sometimes difficult in pancreatic cancer (PC). We aimed to verify whether monitoring of serum tumor markers (TMs), namely carcinoembryonic antigen, CA19-9, DUPAN-2, SPan-1, can facilitate earlier confirmation of treatment failure. Methods: Monitoring of serum TMs and computed tomography were performed every 4 weeks until progression of disease in 90 patients with PC undergoing gemcitabine therapy. In Group A (January 2006 October 2007), we analyzed the fluctuation rates of TMs with high pretreatment positive rates, and defined the criteria of progressive disease under TM monitoring (TM-PD). In Group B (November 2007 October 2008), we calculated the time to progression (TTP) under this TM-PD criteria, which was compared with the UP under the RECIST criteria. Results: CA19-9 and SPan-1 had the highest pretreatment positive rates: 83% and 90%, respectively. In Group A (CA19-9, n = 38; SPan-1, n = 36), TM-PD criteria were defined as follows: fluctuation rates were >25% for a month or >= 10% for 2 consecutive months in CA19-9, and >= 10% for a month in SPan-1. In Group B (CA19-9, n = 18; SPan-1, n = 17), under these criteria, one-month earlier confirmation of treatment failure was feasible in 61% by CA19-9 and 59% by SPan-1. Furthermore, the combination could facilitate this determination in 72% (35/49), significantly better than CA19-9 alone (P = 0.004). Conclusion: Monitoring of serum CA19-9 and Span-1 is helpful for earlier confirmation of treatment failure during gemcitabine therapy in PC

Time trends (2012–2020) in glycated hemoglobin and adherence to the glycemic targets recommended for elderly patients by the Japan Diabetes Society/Japan Geriatrics Society Joint Committee among memory clinic patients with diabetes mellitus

ABSTRACT Aims/Introduction To investigate the changes in the glycated hemoglobin (HbA1c) levels and the relative status of the glycemic control related to the new glycemic targets recommended by the Japan Diabetes Society/Japan Geriatrics Society Joint Committee in 2016 in patients with diabetes mellitus visiting a memory clinic from 2012 to 2020. Materials and Methods This cross‐sectional study included 1,436 patients aged ≥65 years with diabetes. Patients were categorized into three categories as follows: category I, intact cognitive function and activities of daily living (ADL); category II, mild cognitive deficits or impaired instrumental ADL; and category III, moderate to severe cognitive impairment or impaired basic ADL. Trends in HbA1c levels, glycemic control status (optimally/poorly/excessively controlled) and proportion of individuals receiving drugs potentially associated with severe hypoglycemia among all patients and categories (I, II or III) from 2012 to 2020 were examined using linear, logistic and multinominal logistic regression models adjusted for confounding factors. Results Between 2012 and 2020, the HbA1c levels, as well as the proportion of patients with poor glycemic control, increased, whereas the proportion of patients with excessive glycemic control and those receiving drugs potentially associated with severe hypoglycemia decreased. Conclusions Increased levels of HbA1c and decreased proportions of individuals under excessive glycemic control might reflect recent treatment strategies that avoid hypoglycemia in older patients. Given the adverse complications associated with hyperglycemia, more flexible and individualized glycemic targets based on comprehensive assessments, including vascular complications and comorbidities, might be necessary