Manabu Kume

Association of toxicity of sorafenib and sunitinib for human keratinocytes with inhibition of signal transduction and activator of transcription 3 (STAT3).

Hand–foot skin reaction is a most common multi-kinase inhibitor-related adverse event. This study aimed to examine whether the toxicity of sorafenib and sunitinib for human keratinocytes was associated with inhibiting signal transduction and activator of transcription 3 (STAT3). We studied whether STAT3 activity affects sorafenib- and sunitinib-induced cell growth inhibition in HaCaT cells by WST-8 assay. Stattic enhanced the cell-growth inhibitory and apoptotic effects of sorafenib and sunitinib. HaCaT cells transfected with constitutively-active STAT3 (STAT3C) were resistant to the sorafenib- and sunitinib-induced cell growth inhibition. STAT3 activity decreased after short-term treatment with sorafenib and sunitinib in a dose-dependent manner and recovered after long-term treatment with sorafenib and sunitinib at low doses. Moreover, the expression of survivin and bcl-2 decreased after treatment with sorafenib and sunitinib was concomitant with variations in STAT3 activity. Sorafenib-induced STAT3 inhibition was mediated by regulation via MAPK pathways in HaCaT cells, while sunitinib-induced STAT3 inhibition was not. Thus, STAT3 activation mediating apoptosis suppressors may be a key factor in sorafenib and sunitinib-induced keratinocyte cytotoxicity.

Apoptotic Effects of the Extracts of Cordyceps militaris via Erk Phosphorylation in a Renal Cell Carcinoma Cell Line

Cordyceps militaris (CM) is gaining attention as a traditional medicinal food, but its molecular biological mechanisms for anti‐cancer activity are not identified or clarified. We aimed to elucidate the synthesizing apoptotic effects of CM extracts and to determine the biological effects of CM extract against cordycepin alone in a renal cell carcinoma (RCC) cell line. CM extract showed higher effects of growth inhibition, apoptotic effect, and cell cycle arrest than cordycepin alone. Moreover, CM extract activated extracellular signal‐regulated kinase (Erk) highly more than cordycepin alone. We suggest that cordycepin and CM extract induced apoptosis via the activation of Erk dominantly and AMP‐activated protein kinase slightly; CM extract has more potent effects on apoptotic effects associated with Erk activation than cordycepin alone. Copyright

Potentially inappropriate medications in elderly Japanese patients: effects of pharmacists’ assessment and intervention based on Screening Tool of Older Persons’ Potentially Inappropriate Prescriptions criteria ver.2

The Screening Tool of Older Persons’ Potentially Inappropriate Prescriptions (stopp) criteria were updated in 2014 (stopp criteria ver.2), but few studies have evaluated the usefulness of stopp criteria in elderly patients. This prospective observational study evaluated the prevalence of potentially inappropriate medications (PIMs), and the efficacy of hospital pharmacists’ assessment and intervention based on stopp criteria ver.2.

Everolimus-induced human keratinocytes toxicity is mediated by STAT3 inhibition

BackgroundMammalian target of rapamycin (mTOR) inhibitors are associated with dermatological adverse events. The chief aim of this study was to examine the relation between the signal transducer and activator of transcription 3 (STAT3) protein and the dermatological adverse events associated with the mTOR inhibitor everolimus.MethodsWe evaluated the effects of STAT3 activity and related signal transduction activities on everolimus-induced cell growth inhibition in the human keratinocyte HaCaT cell line via a WST-8 assay, and on signal transduction mechanisms involved in everolimus treatments via a western blot analysis. Apoptosis was evaluated using an imaging cytometric assay.ResultsThe cell growth inhibitory effects of everolimus were enhanced by stattic or STA-21, which are selective inhibitors of STAT3, treatment in HaCaT cells, although such effects were not observed in Caki-1 and HepG2 cells. Phosphorylation at tyrosine 705 of STAT3 was decreased by treatment with everolimus in a dose-dependent manner in HaCaT cells; in contrast, phosphorylation at serine 727 was not decreased by everolimus, but slightly increased. Furthermore, we found that pretreatment of p38 MAPK inhibitor and transfection with constitutively active form of STAT3 in HaCaT cells resisted the cytostatic activity of everolimus.ConclusionsThese findings suggest that STAT3 activity may be a biomarker of everolimus-induced dermatological toxicity.

Changes in blood concentrations of trace metals in cancer patients receiving cisplatin-based chemotherapy.

The administration of cisplatin (CDDP) may influence trace metal concentrations in body fluids. In order to test this hypothesis, the blood concentrations of trace metals were determined during the present study in eight Japanese esophageal and lung cancer patients receiving CDDP-based chemotherapy. The levels of manganese, iron (Fe), cobalt, copper, zinc (Zn), platinum and lead in the plasma were determined by inductively coupled plasma-mass spectrometry. In addition, the serum levels of Fe, transferrin and ferritin were evaluated. The baseline plasma concentration of Fe in patients with esophageal cancer was significantly lower than that in lung cancer patients (P=0.011), although there were no significant differences identified with respect to the plasma levels of other trace metals. The data obtained from six fasting patients without blood transfusion demonstrated that plasma concentrations of Fe increased 3.5-fold soon after CDDP treatment and returned to baseline levels ~10 days after therapy. The excessive Fe levels in the bloodstream induced changes in serum ferritin and transferrin levels. Furthermore, serum Zn levels increased 1.8-fold in the 1-3 days following CDDP treatment, and serum cystatin C levels transiently increased. These findings indicate that serum Fe and Zn levels may be useful to understanding the physiological responses in the early stages of CDDP-based chemotherapy, which may be associated with systemic inflammation and/or tissue distribution of CDDP.

Effects of Ascorbyl-2-phosphate Magnesium on Human Keratinocyte Toxicity and Pathological Changes by Sorafenib

Hand-foot skin reaction is recognized as one of the most common adverse events related to multiple tyrosine kinase inhibitors, but an effective prevention method has not been identified. The chief aim of this study was to find a mechanism-based preventive method for the skin toxicity induced by sorafenib using vitamin C derivatives. The effects of ascorbyl-2-phosphate magnesium (P-VC-Mg) on the molecular and pathological changes induced by sorafenib were investigated in human keratinocyte HaCaT cells. The cell growth inhibition and apoptotic effects of sorafenib were attenuated by P-VC-Mg. Moreover, P-VC-Mg inhibited the decrease of signal transducer and activator of transcription 3 (STAT3) phosphorylation and the expression of apoptosis suppressors treated by sorafenib. HaCaT cells transfected with the STAT3 dominant-negative form (STAT3DN) and STAT3 small interfering RNA (siRNA) combined with P-VC-Mg did not exhibit the attenuation of cell growth inhibition. Interestingly, after exposure to sorafenib in a three dimensional (3D) skin model assay, the basal layer was significantly thickened and the granular and spinous layers became thinner. In contrast, after exposure to sorafenib with P-VC-Mg, the thickness of the basal, granular, and spinous layers was similar to that of the control image. These findings suggest that P-VC-Mg attenuates sorafenib-induced apoptosis and pathological changes in human keratinocyte cells and in the 3D skin model mediated by the maintenance of STAT3 activity.