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Ependymal cilia play pivotal roles in cerebrospinal fluid flow. In the primary culture system, undifferentiated glial cells differentiate well into ependymal multiciliated cells (MCCs) in the absence of fetal bovine serum (FBS). However, the substances included in FBS which inhibit this differentiation process have not been clarified yet. Here, we constructed the polarized primary culture system of ependymal cells using a permeable filter in which they retained ciliary movement. We found that transforming growth factor-β1 (TGF-β1) as well as Bone morphogenetic protein (BMP)-2 inhibited the differentiation with ciliary movement. The inhibition on the differentiation by FBS was recovered by the TGF-β1 and BMP-2 inhibitors in combination.

Despite increased aerobic glycolysis is generally seen in human cancers, pancreatic ductal adenocarcinoma (PDAC) cells keep alive in glycolysis-suppressed conditions (1). Here, we sought there are potential therapeutic targets in glycolysis-suppressed PDAC cells. By screening anti-cancer metabolism compounds, we identified SP2509, a selective lysine specific demethylase 1 (LSD1) inhibitor (2). We also tested the effect of another three LSD1 inhibitors (Iadademstat, OG-L002 and T-3775440) on PDAC cells viability. The results showed that OG-L002, but not Iadademstat or T-3775440, lowered glycolysis-suppressed PDAC cells viability, like SP2509. Importantly, only knockdown of LSD1 or LSD2 failed to lower the viability of glycolysis suppressed PDAC cells. In our previous study, we proved that glucose-starvation make PDAC cells yield survival to mitochondrial oxidative phosphorylation (1). In this study, we cleared fatty acids metabolism played a crucial role for glycolysis suppressed PDAC cells survival. Then, we confirmed that SP2509 and OG-L002 can lead lipid droplets accumulation in glycolysis-suppressed conditions. In conclusion, our results showed that SP2509 and OG-L002 may involve regulatory effects on lipid droplets homeostasis, which control storage and release of fatty acids, not only by targeting LSD1 or LSD2. Moreover, SP2509 and OG-L002 significantly lowered viability of glycolysis-suppressed PDAC cells, supposing a novel therapeutic potential of approaches to override resistance of glucose-starvation in PDAC cells. 1.Shiratori R, Furuichi K, Yamaguchi M, Miyazaki N, Aoki H, Chibana H, et al. Glycolytic suppression dramatically changes the intracellular metabolic profile of multiple cancer cell lines in a mitochondrial metabolism-dependent manner. Sci Rep. 2019;9(1):18699. 2.Fiskus W, Sharma S, Shah B, Portier BP, Devaraj SGT, Liu K, et al. Highly effective combination of LSD1 (KDM1A) antagonist and pan-histone deacetylase inhibitor against human AML cells. Leukemia. 2017;31(7):1658. Citation Format: Zhiheng Zhang, Haruna Aoki, Keitaro Umezawa, Taichi Oshima, Takuya Hirao, Yuri Miura, Kousei Ito, Shigeki Aoki. Several LSD1 inhibitors have a potential to disturb fatty acid metabolism necessary &It glycolysis-inhibited pancreatic cancers to survive [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2673.

Tyrosine kinase inhibitors (TKIs) are widely utilized in clinical practice to treat carcinomas, but secondary tumor resistance during chronic treatment can be problematic. AKR1B1 and AKR1B10 of the aldo-keto reductase (AKR) superfamily are highly expressed in cancer cells and are believed to be involved in drug resistance. The aim of this study was to understand how TKI treatment of chronic myelogenous leukemia (CML) cells changes their glucose metabolism and if inhibition of AKRs can sensitize CML cells to TKIs. K562 cells were treated with the TKIs imatinib, nilotinib, or bosutinib, and the effects on glucose metabolism, cell death, glutathione levels, and AKR levels were assessed. To assess glucose dependence, cells were cultured in normal and low-glucose media. Pretreatment with AKR inhibitors, including epalrestat, were used to determine AKR-dependence. Treatment with TKIs increased intracellular glucose, AKR1B1/10 levels, glutathione oxidation, and nuclear translocation of nuclear factor erythroid 2-related factor 2, but with minimal cell death. These effects were dependent on intracellular glucose accumulation. Pretreatment with epalrestat, or a selective inhibitor of AKR1B10, exacerbated TKI-induced cell death, suggesting that especially AKR1B10 was involved in protection against TKIs. Thus, by disrupting cell protective mechanisms, AKR inhibitors may render CML more susceptible to TKI treatments.

Tyrosine kinase inhibitors (TKI), including imatinib (IM), improve the outcome of CML therapy. However, TKI treatment is long-term and can induce resistance to TKI, which often leads to a poor clinical outcome in CML patients. Here, we examined the effect of continuous IM exposure on intracellular energy metabolism in K562 cells, a human Philadelphia chromosome-positive CML cell line, and its subsequent sensitivity to anti-cancer agents. Contrary to our expectations, we found that continuous IM exposure increased sensitivity to TKI. Cancer energy metabolism, characterized by abnormal glycolysis, is linked to cancer cell survival. Interestingly, glycolytic activity was suppressed by continuous exposure to IM, and autophagy increased to maintain cell viability by compensating for glycolytic suppression. Notably, increased sensitivity to TKI was not caused by glycolytic inhibition but by altered intracellular signaling, causing glycolytic suppression and increased autophagy, as evidenced by suppression of p70 S6 kinase 1 (S6K1) and activation of AMP-activated protein kinase (AMPK). Using another human CML cell line (KCL22 cells) and BCR/ABL+ Ba/F3 cells (mimicking Philadelphia chromosome-positive CML cells) confirmed that suppressing S6K1 and activating AMPK increased sensitivity to TKI. Furthermore, suppressing S6K1 and activating AMPK had a synergistic anti-cancer effect by inhibiting autophagy in the presence of TKI. The present study provides new insight into the importance of signaling pathways that affect cellular energy metabolism, and suggests that co-treatment with agents that disrupt energy metabolic signaling (using S6K1 suppressors and AMPK activators) plus blockade of autophagy may be strategies for TKI-based CML therapy.

// Shigeki Aoki 1, * , Michie Morita 1, * , Takuya Hirao 1 , Masashi Yamaguchi 2 , Reika Shiratori 1 , Megumi Kikuya 1 , Hiroji Chibana 2 and Kousei Ito 1 1 Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba-city, Chiba 260-8675, Japan 2 Medical Mycology Research Center, Chiba University, Chiba-city, Chiba 260-8673, Japan * These authors have contributed equally to this work Correspondence to: Shigeki Aoki, email: aokishigeki@chiba-u.jp Keywords: ALL, autophagy, glucocorticoids, glycolysis, oxidative phosphorylation Received: June 16, 2017 Accepted: September 21, 2017 Published: October 09, 2017 ABSTRACT Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Treatments include glucocorticoids (GCs) such as dexamethasone (Dex) and prednisolone, which may be of value when used alongside cytotoxic anti-cancer drugs. To predict therapeutic efficacy of GCs, their activity against ALL cells is usually examined prior to chemotherapy; however, few studies have examined their effects when used in combination with other drugs. The paradox is that cytotoxic anti-cancer drugs that are effective against proliferating cancer cells show synergistic effects when used with GCs that prevent cell proliferation. To address this point, we investigated intracellular energy metabolism in ALL CCRF-CEM cell clones classified according to their sensitivity to Dex and cytotoxic anti-cancer drugs in bulk cultures of mixed cells. We found that Dex suppressed glycolysis, the most important metabolic system in cancer cells, in cells that were damaged by etoposide (a cytotoxic anti-cancer drug), and the cells showed a concomitant increase in mitochondrial oxidative phosphorylation. Furthermore, autophagy, an intracellular bulk degradation system, regulated mitochondrial viability. We also found that mitochondria, whose function is enhanced by Dex, were susceptible to anti-cancer drugs that inhibit respiratory complexes (e.g., etoposide and daunorubicin), resulting in increased production of reactive oxygen species and subsequent cytotoxicity. Taken together, the present study points the way toward a more accurate prediction of the sensitivity of ALL cells to the combined action of anti-cancer drugs and GCs, by taking into consideration the shift in intracellular energy metabolism caused by GCs: namely, from glycolysis to mitochondrial oxidative phosphorylation mediated by autophagy.

Word2vec is a tool that produces a vector representation of words from a large amount of text data. In this paper, we show that only a part of the vector space produced by word2vec is enough to represent the collective sense of a set of related words in the Japanese WordNet. Further, we will show that there is a subspace in the vector space which do not relate to the collective sense. We construct a compact decision tree by using the vectors in order to distinguish whether a given word belongs to the set of related words.

Clenbuterol is a long-acting β2-adrenoceptor agonist and bronchodilator that is used for the treatment of asthma, but the desired activities reside almost exclusively in the (-)-R-enantiomer. This study examined enantioselectivity in the disposition of clenbuterol following administration of clenbuterol racemate to rats. Concentrations of clenbuterol enantiomers in plasma, urine and bile were determined by LC-MS/MS assay with a Chirobiotic T column. This method was confirmed to show high sensitivity, specificity and precision, and clenbuterol enantiomers in 0.1 ml volumes of plasma were precisely quantified at concentrations as low as 0.25 ng/ml. The pharmacokinetic profiles of clenbuterol enantiomers following intravenous and intraduodenal administration of clenbuterol racemate (2 mg/kg) in rats were significantly different. The distribution volume of (-)-R-clenbuterol (9.17 l/kg) was significantly higher than that of (+)-S-clenbuterol (4.14 l/kg). The total body clearance of (-)-R-clenbuterol (13.5 ml/min/kg) was significantly higher than that of the (+)-S-enantiomer (11.5 ml/min/kg). An in situ absorption study in jejunal loops showed no difference in the residual amount between the (-)-R- and (+)-S-enantiomers. Urinary clearance was the same for the two enantiomers, but biliary excretion of (-)-R-clenbuterol was higher than that of the (+)-S-enantiomer. The fractions of free (non-protein-bound) (-)-R- and (+)-S-clenbuterol in rat plasma were 48.8% and 33.1%, respectively. These results indicated that there are differences in the distribution and excretion of the clenbuterol enantiomers, and these may be predominantly due to enantioselective protein binding.

Word2vec is a tool that produces vector representation of words from a large amount of text data. In this paper, we show that only a part of the vector space produced by word2vec is enough to represent the collective sense of a set of related words in the Japanese Word Net. Further, we will show that there is a subspace in the vector space which do not relate to the collective sense. We construct a compact decision tree by using the vectors in order to distinguish whether a given word belongs to the set of related words.

Lexical database the Japanese WordNet is a useful tool in natural language processing. However, it is officially announced that the Japanese WordNet contains 5% errors. In this paper, we classify errors in the Japanese WordNet and discuss error detection methods.

We have observed a photoinduced phase transition (PIPT) in a spin-crossover Fe (II) complex Nafion–[Fe(Htrz) 3 ] film (Nafion is an ion exchange polymer film, and Htrz=1, 2, 4-1H-triazole) from a low-spin (LS) state ( S =0) to a high-spin (HS) state ( S =2) below 150 K. The phototransferred HS state relaxes to the initial LS state, exhibiting a nonexponential time behavior, which has been interpreted in terms of the critical nucleation and subsequent growth of the LS clusters. We have also observed that the decay time τ c is approximately temperature-independent in the low temperature range of 4.2–20 K, and then decreases exponentially with temperature.

Clenbuterol is a long-acting β2-adrenoceptor agonist and bronchodilator that is used for the treatment of asthma, but the desired activities reside almost exclusively in the (-)-R-enantiomer. This study examined enantioselectivity in the disposition of clenbuterol following administration of clenbuterol racemate to rats. Concentrations of clenbuterol enantiomers in plasma, urine and bile were determined by LC-MS/MS assay with a Chirobiotic T column. This method was confirmed to show high sensitivity, specificity and precision, and clenbuterol enantiomers in 0.1 ml volumes of plasma were precisely quantified at concentrations as low as 0.25 ng/ml. The pharmacokinetic profiles of clenbuterol enantiomers following intravenous and intraduodenal administration of clenbuterol racemate (2 mg/kg) in rats were significantly different. The distribution volume of (-)-R-clenbuterol (9.17 l/kg) was significantly higher than that of (+)-S-clenbuterol (4.14 l/kg). The total body clearance of (-)-R-clenbuterol (13.5 ml/min/kg) was significantly higher than that of the (+)-S-enantiomer (11.5 ml/min/kg). An in situ absorption study in jejunal loops showed no difference in the residual amount between the (-)-R- and (+)-S-enantiomers. Urinary clearance was the same for the two enantiomers, but biliary excretion of (-)-R-clenbuterol was higher than that of the (+)-S-enantiomer. The fractions of free (non-protein-bound) (-)-R- and (+)-S-clenbuterol in rat plasma were 48.8% and 33.1%, respectively. These results indicated that there are differences in the distribution and excretion of the clenbuterol enantiomers, and these may be predominantly due to enantioselective protein binding.