Sulfide-Induced Dimerization Versus Demetallation of Tricopper(I) Clusters Protected by Tris-Thiolato Metalloligands

Goo Z.L., Yoshinari N., Yasukawa Y., et al. Sulfide-Induced Dimerization Versus Demetallation of Tricopper(I) Clusters Protected by Tris-Thiolato Metalloligands. Chemistry - An Asian Journal 19, e202400266 (2024); https://doi.org/10.1002/asia.202400266.Here, we report the reactivity of copper(I) clusters toward sulfide ions; these sulfide copper(I) clusters have attracted much attention due to their relevance to biologically active centers and their fascinating structural and photophysical properties. Treatment of the CuI3RhIII2 pentanuclear complex, [Cu3{Rh(aet)3}2]3+ (aet=2-aminoethanethiolate), in which a {CuI3}3+ cluster moiety is bound by two fac-[Rh(aet)3] metalloligands, with NaSH in water produced the CuI6RhIII4 decanuclear complex, [Cu6S{Rh(aet)3}4]4+, accompanied by the dimerization of [Cu3{Rh(aet)3}2]3+ and the incorporation of a sulfide ion at the center. While similar treatment using the analogous CuI3IrIII2 complex with fac-[Ir(aet)3] metalloligands, [Cu3{Ir(aet)3}2]3+, produced the isostructural CuI6IrIII4 decanuclear complex, [Cu6S{Ir(aet)3}4]4+, the use of the CuI3RhIII2 complex with fac-[Rh(apt)3] metalloligands, [Cu3{Rh(apt)3}2]3+ (apt=3-aminopropanethiolate), resulted in the removal of one of the three CuI atoms from {CuI3}3+ to afford the CuI2RhIII2 tetranuclear complex, [Cu2{Rh(apt)3}2]2+

Sarcopenia, intramuscular fat deposition, and visceral adiposity independently predict the outcomes of hepatocellular carcinoma

Background & AimsObesity defined by body mass index (BMI) significantly increases the risk of hepatocellular carcinoma (HCC). In contrast, not only obesity but also underweight is associated with poor prognosis in patients with HCC. Differences in body composition rather than BMI were suggested to be true determinants of prognosis. However, this hypothesis has not been demonstrated conclusively.MethodsWe measured skeletal muscle index (SMI), mean muscle attenuation (MA), visceral adipose tissue index, subcutaneous adipose tissue index, and visceral to subcutaneous adipose tissue area ratios (VSR) via computed tomography in a large-scale retrospective cohort of 1257 patients with different stages of HCC, and comprehensively analyzed the impact of body composition on the prognoses.ResultsAmong five body composition components, low SMI (called sarcopenia), low MA (called intramuscular fat [IMF] deposition), and high VSR (called visceral adiposity) were significantly associated with mortality, independently of cancer stage or Child-Pugh class. A multivariate analysis revealed that sarcopenia (hazard ratio [HR], 1.52; 95% confidence interval [CI], 1.18–1.96; p=0.001), IMF deposition (HR, 1.34; 95% CI, 1.05–1.71; p=0.020), and visceral adiposity (HR, 1.35; 95% CI, 1.09–1.66; p=0.005) but not BMI were significant predictors of survival. The prevalence of poor prognostic body composition components was significantly higher in underweight and obese patients than in normal weight patients.ConclusionsSarcopenia, IMF deposition, and visceral adiposity independently predict mortality in patients with HCC. Body composition rather than BMI is a major determinant of prognosis in patients with HCC

Thymidine Catabolism as a Metabolic Strategy for Cancer Survival

Thymidine phosphorylase (TP), a rate-limiting enzyme in thymidine catabolism, plays a pivotal role in tumor progression; however, the mechanisms underlying this role are not fully understood. Here, we found that TP-mediated thymidine catabolism could supply the carbon source in the glycolytic pathway and thus contribute to cell survival under conditions of nutrient deprivation. In TP-expressing cells, thymidine was converted to metabolites, including glucose 6-phosphate, lactate, 5-phospho-α-D-ribose 1-diphosphate, and serine, via the glycolytic pathway both in vitro and in vivo. These thymidine-derived metabolites were required for the survival of cells under low-glucose conditions. Furthermore, activation of thymidine catabolism was observed in human gastric cancer. These findings demonstrate that thymidine can serve as a glycolytic pathway substrate in human cancer cells

Thymidine catabolism promotes NADPH oxidase-derived reactive oxygen species (ROS) signalling in KB and yumoto cells

Thymidine phosphorylase (TP) is a rate-limiting enzyme in the thymidine catabolic pathway. TP is identical to platelet-derived endothelial cell growth factor and contributes to tumour angiogenesis. TP induces the generation of reactive oxygen species (ROS) and enhances the expression of oxidative stress-responsive genes, such as interleukin (IL)-8. However, the mechanism underlying ROS induction by TP remains unclear. In the present study, we demonstrated that TP promotes NADPH oxidase-derived ROS signalling in cancer cells. NADPH oxidase inhibition using apocynin or small interfering RNAs (siRNAs) abrogated the induction of IL-8 and ROS in TP-expressing cancer cells. Meanwhile, thymidine catabolism induced by TP increased the levels of NADPH and intermediates of the pentose phosphate pathway (PPP). Both siRNA knockdown of glucose 6-phosphate dehydrogenase (G6PD), a rate-limiting enzyme in PPP, and a G6PD inhibitor, dihydroepiandrosterone, reduced TP-induced ROS production. siRNA downregulation of 2-deoxy-D-ribose 5-phosphate (DR5P) aldolase, which is needed for DR5P to enter glycolysis, also suppressed the induction of NADPH and IL-8 in TP-expressing cells. These results suggested that TP-mediated thymidine catabolism increases the intracellular NADPH level via the PPP, which enhances the production of ROS by NADPH oxidase and activates its downstream signalling

Advanced Technologies for Oral Controlled Release: Cyclodextrins for oral controlled release

Cyclodextrins (CDs) are used in oral pharmaceutical formulations, by means of inclusion complexes formation, with the following advantages for the drugs: (1) solubility, dissolution rate, stability and bioavailability enhancement; (2) to modify the drug release site and/or time profile; and (3) to reduce or prevent gastrointestinal side effects and unpleasant smell or taste, to prevent drug-drug or drug-additive interactions, or even to convert oil and liquid drugs into microcrystalline or amorphous powders. A more recent trend focuses on the use of CDs as nanocarriers, a strategy that aims to design versatile delivery systems that can encapsulate drugs with better physicochemical properties for oral delivery. Thus, the aim of this work was to review the applications of the CDs and their hydrophilic derivatives on the solubility enhancement of poorly water soluble drugs in order to increase their dissolution rate and get immediate release, as well as their ability to control (to prolong or to delay) the release of drugs from solid dosage forms, either as complexes with the hydrophilic (e.g. as osmotic pumps) and/ or hydrophobic CDs. New controlled delivery systems based on nanotechonology carriers (nanoparticles and conjugates) have also been reviewed

Tonsillar metastasis of gastric cancer

Metastasis from a malignant tumor to the palatine tonsils is rare, with only 100 cases reported in the English-language literature. Tonsillar metastasis from a gastric cancer is very rare. We report here a case of palatine tonsillar metastasis after gastric cancer surgery. The patient was an 88-year-old woman who had gastric cancer with abdominal wall invasion. She had undergone a distal gastrectomy with abdominal wall resection and D2 lymph node dissection. Histologically, the tumor was primarily a moderately differentiated adenocarcinoma. It was stage IV (T4, N1, M0) using TNM clinical classification. The patient developed pharyngeal discomfort and abdominal pain and was hospitalized during the follow-up period, 1 year 9 months post-operatively. Multiple lung metastases, Virchow’s lymph node metastasis, and adrenal metastasis were observed. A mass of 2.5 cm was also observed in the right palatine tonsil. It was diagnosed as a moderately differentiated adenocarcinoma, a metastasis from gastric cancer. There was a concern of asphyxiation due to hemorrhage of the tumor; however, the tumor dislodged approximately 10 days after biopsy and tonsillar recurrence was not observed. The patient died 1 year 10 months post-operatively. In the literature there are cases with tonsillar metastases where surgical treatment, radiotherapy, and chemotherapy were performed and extension of survival was seen. Tonsillar metastasis is a form of systemic metastasis of a malignant tumor, and there is a high risk for asphyxiation from tumor dislodgement or hemorrhage. Thus, it is important to recognize tonsillar metastasis as an oncologic emergency

リチウムイオン伝導性Li2S-SiS2-Li3PO4系オキシスルフィドガラスの結晶化に伴う構造変化

The structural change of the (100-x) (0.6Li2S⋅0.4SiS2)⋅xLi3PO4 oxysulfide glasses during crystallization was analyzed by means of solid-state nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS). The unique tetrahedral units of SiOnS4-n (n=1, 2, 3) and POnS4-n (n=1, 2, 3) present in the glass samples vanished and the SiS4, SiO4, PS4 and PO4 units increased with proceeding of the crystallization process. Nonbridging sulfur and oxygen atoms decreased while bridging oxygens and S2- increased with proceeding of the crystallization process. Large structural difference between the glass and the corresponding crystallized sample explained the high stability against crystallization found in the oxysulfide glass with the composition of x=5

Role of Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand in Immune Response to Influenza Virus Infection in Mice

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis of various tumor cells but not normal cells. However, various cytokines and virus infection differentially regulate TRAIL and TRAIL receptor expression. It has been demonstrated that virus infection changes the pattern of human TRAIL-receptor expression on normal cells, which were resistant to TRAIL-mediated apoptosis, and makes them susceptible to TRAIL-mediated apoptosis. Since previous studies on the function of TRAIL have been performed mainly in vitro, its physiological role in the immune response to virus infection remains unknown. In the present study, we investigated the expression of TRAIL in the lungs of influenza virus-infected mice and the function of TRAIL in the immune response to infection. Influenza virus infection increased TRAIL mRNA expression in the lung. TRAIL protein expression was induced on NK cells in the lung 4 days after infection. At 7 days after infection, TRAIL protein expression was also detected on CD4(+) and CD8(+) T cells. However, NK cells and T cells in the lungs of uninfected mice did not express a detectable level of TRAIL on their cell surfaces. DR5, which is a mouse TRAIL receptor, was also induced to express after virus infection. Expression of both TRAIL and DR5 mRNAs was reduced to normal level at 6 weeks after virus infection. Administration of anti-TRAIL monoclonal antibody, which blocks TRAIL without killing TRAIL-expressing cells, to mice during influenza virus infection significantly delayed virus clearance in the lung. These results suggest that TRAIL plays an important role in the immune response to virus infection