Arsenic Disulfide Combined with L-Buthionine-(S, R)-Sulfoximine Induces Synergistic Antitumor Effects in Two-Dimensional and Three-Dimensional Models of MCF-7 Breast Carcinoma Cells.

Three-dimensionally (3D) cultured tumor cells (spheroids) exhibit more resistance to therapeutic agents than the cells cultured in traditional two-dimensional (2D) system (monolayers). We previously demonstrated that arsenic disulfide (As2S2) exerted significant anticancer efficacies in both 2D- and 3D-cultured MCF-7 cells, whereas 3D spheroids were shown to be resistant to the As2S2 treatment. L-buthionine-(S, R)-sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, has been regarded to be a potent candidate for combinatorial treatment due to its GSH modulation function. In the present study, we introduced BSO in combination with As2S2 at a low concentration to investigate the possible enhancing anticancer efficacy by the combinatorial treatment on 2D- and 3D-cultured MCF-7 cells. Our results presented for the first time that the combination of As2S2 and BSO exerted potent anticancer synergism in both MCF-7 monolayers and spheroids. The IC50 values of As2S2 in combinatorial treatment were significantly lower than those in treatment of As2S2 alone in both 2D- and 3D-cultured MCF-7 cells (P<0.01, respectively). In addition, augmented induction of apoptosis and enhanced cell cycle arrest along with the regulation of apoptosis- and cell cycle-related proteins, as well as synergistic inhibitions of PI3K/Akt signals, were also observed following co-treatment of As2S2 and BSO. Notably, the combinatorial treatment significantly decreased the cellular GSH levels in both 2D- and 3D-cultured MCF-7 cells in comparison with each agent alone (P<0.05 in each). Our results suggest that the combinatorial treatment with As2S2 and BSO could be a promising novel strategy to reverse arsenic resistance in human breast cancer.

Plant-derived alkaloid sinomenine potentiates glucocorticoid pharmacodynamics in mitogen-activated human peripheral blood mononuclear cells by regulating the translocation of glucocorticoid receptor.

Sinomenine has been used as an antirheumatic drug in China. Glucocorticoid combined with sinomenine could be an alternative therapeutic approach. In this study, we evaluated the sinomenine potential effect on glucocorticoid pharmacodynamics in vitro using a human peripheral blood mononuclear cell (PBMC) culture system. We also disclosed the possible action mechanism of sinomenine with a focus on P-glycoprotein function and glucocorticoid receptor (GR) translocation into nucleus. The median (range) of methylprednisolone IC50 values against the PBMC proliferation was 3.18 (0.45-6.81) ng/mL, whereas the median (range) IC50 values of methylprednisolone combined with 0.03, 0.3, 3, and 30 µM sinomenine were 1.85 (0.05-5.15), 0.83 (0.10-3.90), 0.56(0.09-1.62), and 0.59(0.05-1.30) ng/mL, respectively. Sinomenine significantly decreased the IC50 values of methylprednisolone and enhanced the immunosuppressive effect of methylprednisolone (p < 0.05). Sinomenine alone regulated the GR translocation in both Jurkat T cells and normal human PBMCs, and the combination of sinomenine and methylprednisolone showed stronger GR-modulatory activity than methylprednisolone alone. Thus, the additive effect of sinomenine to promote the methylprednisolone immunosuppressive efficacy was suggested to be related to nuclear GR-translocation. However, sinomenine did not significantly inhibit the P-glycoprotein function in the activated PBMCs, suggesting that sinomenine's additive effect seemed to be unrelated with the P-glycoprotein inhibition.

Treatment of Myasthenia Gravis With High-Dose Cholinesterase Inhibitors and Calcineurin Inhibitors Caused Spontaneous Muscle Cramps in Patients.

OBJECTIVES: The objective of this study was to investigate the influence of treatment with cholinesterase inhibitors (ChEIs) and calcineurin inhibitors (CNIs) on the occurrence of cramps in myasthenia gravis (MG) patients. METHODS: The frequency and duration of cramp and serum electrolytes were evaluated in 81 patients with MG. The patients were classified using Myasthenia Gravis Foundation of America postintervention status scores based on the treatment and the responsiveness to the treatment. Quantitative MG score, MG activities of daily living score, MG composite score, or MG quality of life 15 score was used to assess the health-related quality of life (QOL). RESULTS: Muscle cramps developed in 44 (54.3%) of 81 MG patients. The scores of MG activities of daily living, MG composite, or MG-QOL 15-item questionnaire in patients with cramp were significantly higher than those in patients without cramps (P = 0.002, P = 0.01, or P = 0.0022, respectively). The serum magnesium concentrations were lower in patients treated with CNI (n = 16) than in those not treated with CNI (n = 65) (P = 0.002). The probability of cramps was significantly higher in patients treated with ChEIs (≥180 mg/d) in addition to CNI than in patients who were treated with a low dose of ChEIs (≤60 mg/d) without concomitant CNI treatment (P = 0.017). CONCLUSIONS: Our data suggested that treatment with a high dose of ChEI and CNI accelerated the probability of cramps and reduced the QOL in MG patients.

Influence of High-Dose Folic Acid on Methotrexate Efficacies and Safety in Japanese Rheumatoid Arthritis Patients.

Backgrounds Folic acid dose at ≦5 mg/week has been recommended for rheumatoid arthritis (RA) patients to decrease risk of methotrexate adverse effects. However, higher doses of folic acid is used in some cases. We examined the influence of high-dose folic acid on methotrexate efficacies and safety in Japanese RA patients. Methods 502 RA patients of four hospitals prescribed methotrexate and folic acid were included. These patients were divided into two subgroups according to the threshold of folic acid dose by 5 mg/week. Basic patient characteristics, methotrexate doses, and the efficacies or adverse effects of methotrexate were retrospectively compared between the two patient subgroups. Results The frequency of folic acid use at doses higher than 5 mg/week was significantly different between the four hospitals (P<0.001). The prevalence of methotrexate adverse effects was not significantly different between the patients taking folic acid less and more than 5 mg/week. However, in the lower dose methotrexate subgroup (≦8 mg/week), the prevalence of patients exhibiting abnormal serum ALT concentrations in the patients using higher (>5 mg/week) dose of folic acid was significantly higher than that in the lower (≦5 mg/week) folic acid-treated subgroup (P=0.029). Folic acid dose between patients taking methotrexate less and more than 8 mg/week was not significantly different. Major conclusion Folic acid dose was dependent on the hospitals, while efficacies and hepatotoxicity of methotrexate was not basically different between patients taking less and more than 5 mg/week of folic acid.

[A case of interstitial pneumonia exacerbated by kampo-induced pneumonitis].

A 65-year-old woman who had complained of non-productive cough since May 1998 visited our hospital on November 5, 2000. She had been treated at another hospital with Kampo (Chinese herbal medicine), including Moku-boui-to, Bakumon-do-to, and Saiko-keishi-kankyo-to for chronic non-productive cough. Chest radiographs and CT films showed the reticular shadows that had been present in 1998, in both lower lung fields, and also demonstrated new reticular shadows in the right upper lung field and left lingular segment. Laboratory data revealed hypoxemia and pulmonary function tests revealed restrictive ventilatory disturbance, so she was admitted to our hospital on November 9, 2000. After the cessation of Kampo treatment, her symptoms disappeared, and the hypoxemia, restrictive disturbance, and reticular shadows in the chest radiograph gradually improved. Video-assisted lung biopsy specimens showed thickened alveolar walls with lymphocyte and eosinophil infiltration. A leukocyte migration test was positive for Moku-boui-to, Bakumon-do-to, and weakly positive for Saiko-keishi-kankyo-to. Although no challenge test for Kampo was performed, we diagnosed this case as interstitial pneumonia exacerbated Kampo-induced pneumonitis based on these clinical, laboratory and histological findings.