A model-based pharmacokinetic assessment of drug-drug interaction between tacrolimus and nirmatrelvir/ritonavir in a kidney transplant patient with COVID-19.

We experienced a patient with a remarkable and prolonged increase in tacrolimus blood concentrations when nirmatrelvir/ritonavir was concomitantly used. The inhibitory intensity and duration of nirmatrelvir/ritonavir on tacrolimus pharmacokinetics were examined using a model-based analysis. A renal transplant patient taking oral tacrolimus continuously was treated with nirmatrelvir/ritonavir for 5 days. The baseline tacrolimus trough blood concentration was 4.2 ng/mL. Tacrolimus was discontinued on Day 6 after the concomitant administration of nirmatrelvir/ritonavir, and the trough concentration increased to 96.4 ng/mL on Day 7. The model-based analysis showed that tacrolimus clearance decreased to 35% and bioavailability increased by 18.7-fold after the coadministration of nirmatrelvir/ritonavir, compared with before the coadministration. Therefore, nirmatrelvir/ritonavir drastically decreased both the apparent clearance and apparent volume of distribution. Simulated tacrolimus concentrations could be best fitted to the observed concentrations when the inhibitory effects of nirmatrelvir/ritonavir were modeled to disappear over about 10 days by first-order elimination. In conclusion, nirmatrelvir/ritonavir greatly increases tacrolimus concentrations by not only reducing clearance, but also increasing bioavailability. Interactions between nirmatrelvir/ritonavir and low-bioavailability drugs which are substrates for CYP3A and P-glycoprotein, such as tacrolimus, are harmful, and concomitant use of these medicines should be avoided.

Antibiotic Resistance in Non-Typhoidal Salmonella enterica Strains Isolated from Chicken Meat in Indonesia.

The increase in antibiotic resistance in non-typhoidal Salmonella enterica (NTS) has been confirmed in Indonesia by this study. We confirmed the virulence genes and antimicrobial susceptibilities of clinical NTS (n = 50) isolated from chicken meat in Indonesia and also detected antimicrobial resistance genes. Of 50 strains, 30 (60%) were non-susceptible to nalidixic acid (NA) and all of them had amino acid mutations in gyrA. Among 27 tetracycline (TC) non-susceptible strains, 22 (81.5%) had tetA and/or tetB. The non-susceptibility rates to ampicillin, gentamicin or kanamycin were lower than that of NA or TC, but the prevalence of blaTEM or aadA was high. Non-susceptible strains showed a high prevalence of virulence genes compared with the susceptible strains (tcfA, p = 0.014; cdtB, p < 0.001; sfbA, p < 0.001; fimA, p = 0.002). S. Schwarzengrund was the most prevalent serotype (23 strains, 46%) and the most frequently detected as multi-antimicrobial resistant. The prevalence of virulence genes in S. Schwarzengrund was significantly higher than other serotypes in hlyE (p = 0.011) and phoP/Q (p = 0.011) in addition to the genes above. In conclusion, NTS strains isolated from Indonesian chicken had a high resistance to antibiotics and many virulence factors. In particular, S. Schwarzengrund strains were most frequently detected as multi-antimicrobial resistant and had a high prevalence of virulence genes.

Sustained Improvements in Antimicrobial Therapy and Clinical Outcomes following a Pharmacist-Led Antimicrobial Stewardship Intervention: Uncontrolled Before-After Study.

Our antimicrobial pharmacist-led intervention included: (a) a structured review of antibiotic prescriptions; (b) educating prescribers on antimicrobial therapy; (c) monthly reporting of department-level rates of blood sampling for culture. Daily review began in May 2018 and was discontinued after 10 months; however, the other interventions were conducted throughout the study period. This study aimed to evaluate the sustained impact of pharmacist's interventions on antimicrobial therapy and clinical outcomes between the baseline (May-December 2017), intervention (May-December 2018), and post-intervention (May-December 2019) periods. The rate of blood culture collections before starting antipseudomonal agent therapy was significantly increased from the baseline to post-intervention periods (71% vs. 85%, p < 0.001). Antipseudomonal agent therapy was more frequently de-escalated in the post-intervention period than in the baseline period (73% vs. 54%, p = 0.038). Total use of antipseudomonal agents was reduced from the baseline to intervention periods and persisted during the post-intervention period (50.5 vs. 41.8 and 42.6 DDD per 1000 patient-days, p = 0.016 and p = 0.022, respectively). During the study period, there were significant reductions in the incidence of hospital-acquired Clostridioides difficile infection (1.12, 0.54, and 0.51 per 10,000 patient-days, respectively, p = 0.031) and 30-day mortality with bacteremia (19%, 18%, and 12%, respectively, p = 0.005). Our pharmacist-led interventions sustainably achieved appropriate antimicrobial therapy and improved clinical outcomes.

Effect of Antimicrobial Stewardship on Oral Quinolone Use and Resistance Patterns over 8 Years (2013-2020).

Since 2014, several global and national guidelines have been introduced to address the problem of antimicrobial resistance. We conducted a campaign in a tertiary hospital to promote appropriate quinolone use through educational lectures in 2018. The aim of this retrospective study was to evaluate the changes in the following: prescription characteristics, trend of oral quinolone use, and antibiotic susceptibility of bacteria from 2013 to 2020. Antimicrobial use was assessed as days of therapy per 1000 patient-days. We found a significant reduction in unnecessary antibiotic prescriptions between December 2013 and December 2020. Significant negative trends were detected in the use of quinolones over 8 years (outpatients, coefficient = -0.15655, p < 0.001; inpatients, coefficient = -0.004825, p = 0.0016). In particular, the monthly mean use of quinolones among outpatients significantly decreased by 11% from 2013 to 2014 (p < 0.05) and reduced further by 31% from 2017 to 2020 (p < 0.001). A significant positive trend was observed in the susceptibility of Pseudomonas aeruginosa to levofloxacin (p < 0.001). These results demonstrate that the use of oral quinolones was further reduced following educational intervention and the bacterial susceptibility improved with optimal quinolone usage compared to that in 2013.

Impact of Cefazolin Shortage on Clinical Outcomes of Adult Patients with Bacteremia Caused by Methicillin-Susceptible Staphylococcus aureus in a Tertiary Care University Hospital.

Cefazolin is an essential antibiotic used for treating bacteremia; in particular, it is recommended as a first-line agent for infections caused by methicillin-susceptible Staphylococcusaureus (MSSA). In March 2019, problems with a major antibiotic supplier caused a critical shortage of cefazolin in Japan; however, the impact of the cefazolin shortage on clinical outcomes remains unknown. This study aimed to evaluate the effect of the cefazolin shortage in patients with MSSA bacteremia. Data from 75 patients were compared between the pre-shortage (March 2018-January 2019, n = 39) and post-shortage (March 2019-January 2020, n = 36) periods. There were no significant differences in the demographic characteristics between the two groups, and the cefazolin shortage did not worsen clinical outcomes such as adverse drug reactions, treatment failure, and 30-day mortality. In the post-shortage group, ampicillin/sulbactam and benzylpenicillin were more frequently administered as alternative antibiotics for empirical and definitive therapy (10% vs. 31%, p = 0.042; 0% vs. 19%, p = 0.004, respectively). Multivariate analysis revealed that the broad-spectrum antibiotics for definitive therapy, such as antipseudomonal penicillin, were associated with treatment failure in patients with MSSA bacteremia (OR = 17, p = 0.003). Hence, narrow-spectrum antibiotics should be prescribed for MSSA bacteremia as alternatives during a cefazolin shortage.

Effect of educational intervention on the appropriate use of oral antimicrobials in oral and maxillofacial surgery: a retrospective secondary data analysis.

BACKGROUND: In Japan, oral third-generation cephalosporins with broad-spectrum activity are commonly prescribed in the practices of dentistry and oral surgery. However, there are few reports on the appropriate use of antibiotics in the field of oral surgery. This study aimed to evaluate the appropriateness of antibiotic use before and after an educational intervention in the Department of Oral and Maxillofacial Surgery, Kobe University Hospital. METHODS: The use of oral antibiotics was investigated among inpatients and outpatients before and after an educational intervention conducted by the antimicrobial stewardship team. Additionally, the frequency of surgical site infection after the surgical removal of an impacted third mandibular molar under general anesthesia and the prevalence of adverse effects of the prescribed antibiotics were comparatively evaluated between 2013 and 2018. RESULTS: After the educational intervention, a remarkable reduction was noted in the prescription of oral third-generation cephalosporins, but increased use of penicillins was noted among outpatients. There was reduced use of macrolides and quinolones in outpatients. Although a similar trend was seen for inpatients, the use of quinolones increased in this population. Despite the change in the pattern of antibiotic prescription, inpatients who underwent mandibular third molar extraction between 2013 and 2018 did not show a significant increase in the prevalence of surgical site infections (6.2% vs. 1.8%, p = .336) and adverse effects of drugs (2.1% vs. 0%, p = .466). CONCLUSIONS: This study suggests that the judicious use of oral antibiotics is possible through conscious and habitual practice of appropriate antibiotic use. However, further investigation is required to develop measures for appropriate use of oral antibiotics.

Risk Factors for the Acquisition of Enterococcus faecium Infection and Mortality in Patients with Enterococcal Bacteremia: A 5-Year Retrospective Analysis in a Tertiary Care University Hospital.

The incidence of bacteremia caused by Enterococcus faecium, which is highly resistant to multiple antibiotics, is increasing in Japan. However, risk factors for the acquisition of E. faecium infection and mortality due to enterococcal bacteremia are not well known. We compared demographic, microbiological, and clinical characteristics using a Cox regression model and univariate analysis. We performed a multivariate analysis to identify risk factors for patients treated between 2014 and 2018. Among 186 patients with enterococcal bacteremia, two groups included in the Kaplan-Meier analysis (E. faecalis (n = 88) and E. faecium (n = 94)) showed poor overall survival in the E. faecium group (HR: 1.92; 95% confidence interval: 1.01-3.66; p = 0.048). The median daily antibiotic cost per patient in the E. faecium group was significantly higher than that in the E. faecalis group ($23 ($13-$34) vs. $34 ($22-$58), p < 0.001). E. faecium strains were more frequently identified with previous use of antipseudomonal penicillins (OR = 4.04, p < 0.001) and carbapenems (OR = 3.33, p = 0.003). Bacteremia from an unknown source (OR = 2.79, p = 0.025) and acute kidney injury (OR = 4.51, p = 0.004) were associated with higher risks of 30-day mortality in patients with enterococcal bacteremia. Therefore, clinicians should provide improved medical management, with support from specialized teams such as those assisting antimicrobial stewardship programs.

The Antimicrobial Resistance Characteristics of Imipenem-Non-Susceptible, Imipenemase-6-Producing Escherichia coli.

Imipenemase-6 (IMP-6) type carbapenemase-producing Enterobacteriaceae is regarded as dangerous due to its unique lack of antimicrobial susceptibility. It is resistant to meropenem (MEPM) but susceptible to imipenem (IPM). In addition to carbapenemase, outer membrane porins and efflux pumps also play roles in carbapenem resistance by reducing the antimicrobial concentration inside cells. Extended-spectrum ß-lactamase (ESBL) is transmitted with IMP-6 by the plasmid and broadens the spectrum of antimicrobial resistance. We collected 42 strains of IMP-6-producing Escherichia coli and conducted a molecular analysis of carbapenemase, ESBL, porin, efflux, and epidemiological characteristics using plasmid replicon typing. Among the 42 isolates, 21 strains were susceptible to IPM (50.0%) and 1 (2.4%) to MEPM. Seventeen strains (40.5%) co-produced CTX-M-2 type ESBL. We found that the relative expression of ompC and ompF significantly correlated with the MIC of IPM (p = 0.01 and p = 0.03, respectively). Sixty-eight% of CTX-M-2-non-producing strains had IncI1, which was significantly different from CTX-M-2-producing strains (p < 0.001). In conclusion, 50.0% of our IMP-6-producing strains were non-susceptible to IPM, which is different from the typical pattern and can be attributed to decreased porin expression. Further studies investigating other types of carbapenemase are warranted.

How Does Antimicrobial Stewardship Affect Inappropriate Antibiotic Therapy in Urological Patients?

Antimicrobial stewardship teams (ASTs) have been well-accepted in recent years; however, their clinical outcomes have not been fully investigated in urological patients. The purpose of this study was to evaluate the outcomes of intervention via a retrospective review of urological patients, as discussed in the AST meetings, who were treated with broad-spectrum antibiotics between 2014 and 2018 at the Department of Urology, Kobe University Hospital in Japan. Interventions were discussed in AST meetings for patients identified by pharmacists as having received inappropriate antibiotic therapy. The annual changes in numbers of inappropriate medications and culture submissions over five years at the urology department were statistically analyzed. Among 1,033 patients audited by pharmacists, inappropriate antibiotic therapy was found in 118 cases (11.4%). The numbers of inappropriate antibiotic use cases and of interventions for indefinite infections had significantly decreased during the study period (p = 0.012 and p = 0.033, respectively). However, the number of blood and drainage culture submissions had significantly increased (p = 0.009 and p = 0.035, respectively). Our findings suggest that urologists have probably become more familiar with infectious disease management through AST intervention, leading to a decrease in inappropriate antibiotic use and an increase in culture submissions.

Efficacy of educational intervention on reducing the inappropriate use of oral third-generation cephalosporins.

PURPOSE: This study aimed to evaluate the efficacy of an educational intervention on reducing the inappropriate use of oral third-generation cephalosporins, the prevalence of resistant bacteria, and clinical outcomes. METHODS: A before-after study was conducted to compare the data for 1 year before and after intervention at a Japanese university hospital. Educational intervention included lectures for all medical staff on oral antibiotics and educational meetings with each medical department. The primary outcome was the use of oral third-generation cephalosporins in inpatients as measured by the monthly median days of therapy (DOTs) per 1000 patient days. Secondary outcomes included the use of each oral antibiotic in inpatients and outpatients, proportion of ß-lactamase-nonproducing ampicillin-resistant Haemophilus influenzae (BLNAR), penicillin-resistant Streptococcus pneumoniae (PRSP) and extended-spectrum ß-lactamase producing Escherichia coli (ESBLEC), the incidence of hospital-acquired Clostridioides difficile infection (HA-CDI), and hospital mortality. RESULTS: The use of oral third-generation cephalosporins in inpatients was significantly decreased after intervention [DOTs (interquartile range): 24.2 (23.5-25.1) vs. 3.7 (0.0-7.1), P < 0.001], and the value in outpatients was also decreased significantly. The use of fluoroquinolones and macrolides did not increase after intervention. The proportion of BLNAR, PRSP and ESBLEC did not change significantly during the study period. The incidence of HA-CDI was significantly decreased, and hospital mortality did not change after intervention. CONCLUSION: Educational intervention was effective in reducing the use of oral third-generation cephalosporins without increasing the use of broad-spectrum antibiotics and worsening clinical outcome. The prevalence of resistant bacteria did not change during the study period.

Antibiotic de-escalation therapy in patients with community-acquired nonbacteremic pneumococcal pneumonia.

Background De-escalation therapy is recommended as an effective antibiotic treatment strategy for several infectious diseases. While there is limited evidence supporting its clinical and cost-effective outcomes in patients with community-acquired bacteremic pneumonia, there is no evidence in patients with nonbacteremic pneumonia. Objective This study aimed to evaluate the antibiotic costs in patients who did and did not receive de-escalation therapy, based on the 2017 Japanese guidelines for the management of community-acquired nonbacteremic pneumococcal pneumonia of the Japanese Respiratory Society (JRS). Setting Kobe university hospital, Japan. Methods A retrospective case series review including antibiotic use and length of hospital stay was conducted using the medical records from April 2008 to May 2019 at a university hospital in Japan. Main outcome measure Impact of antibiotic de-escalation therapy on the antibiotic costs. Results Among 55 patients who were eligible, the treating physicians de-escalated antibiotics in 28 (51%). The differences in the median length of hospital stay and the incidence of adverse drug reactions between the two groups were not statistically significant (p = 0.67 and 1.0, respectively). However, the median total antibiotic cost per infected patient in the de-escalated group was significantly lower than that in the non-de-escalated group [$269.8 ($195-$389) vs. $420.5 ($221-$799), p = 0.048]. Conclusion Antibiotic de-escalation based on the 2017 JRS guidelines leads to a reduction in total antibiotic costs for the management of community-acquired nonbacteremic pneumococcal pneumonia.

Bitterness-Masking Effects of Different Beverages on Zopiclone and Eszopiclone Tablets.

The purpose of the study was to evaluate the ability of different beverages to mask the bitterness of zopiclone and eszopiclone in tablet formulations using the artificial taste sensor and human gustatory sensation testing. The beverages tested for bitterness-masking effects were: Mugicha, Sports beverage, Lactic acid drink, Orange juice and a diluted simple syrup (an 8.5% sucrose solution). The bitterness intensities estimated by the taste sensor of zopiclone or eszopiclone one-tablet solutions mixed with the various beverages, corresponded well with the observed bitterness intensities measured by gustatory sensation testing. The Sports beverage, Lactic acid drink and Orange juice significantly suppressed the bitterness intensity of both zopiclone and eszopiclone 1-tablet solutions compared with water when tested in the artificial taste sensor. Sports beverage, Lactic acid drink and Orange juice all contain citric acid as acidifier, so it was postulated that citric acid was involved in the mechanism of bitterness intensity suppression of zopiclone and eszopiclone 1-tablet solutions by these three beverages. It was then shown that citric acid suppressed the bitterness intensity of a zopiclone one-tablet sample solution in a dose-dependent manner. 1H-NMR spectroscopic analysis of mixtures of citric acid with zopiclone suggested that the carboxyl groups of citric acid interact with the amine group on zopiclone. This study therefore showed that the bitterness intensities of zopiclone and eszopiclone can be suppressed by citric-acid-contained beverages and suggests that this bitterness suppression is due to a direct electrostatic interaction between citric acid and the two drugs.

Bacteremia complicating urinary tract infection by Pseudomonas aeruginosa: Mortality risk factors.

OBJECTIVES: To examine the clinical risk factors for death within 30 days of diagnosis of Pseudomonas aeruginosa-causing bacteremia after a urinary tract infection. METHODS: A total of 62 patients with Pseudomonas aeruginosa isolated from both urine and blood at the same episode from January 2009 to December 2016 were enrolled in the present study. We retrospectively investigated clinical risk factors for death by comparison between surviving patients and those who died within 30 days after diagnosis of P. aeruginosa bacteremia. The comparison for risk factors for bacteremia-related death included 31 categories, such as age, laboratory data, underlying diseases, clinical history, history of surgery, care in the intensive care unit, P. aeruginosa susceptibility to the antibiotics used at the time of bacteremia diagnosis and consultation with urological department. RESULTS: The study included 48 men and 14 women aged 71.3 ± 10.4 years. Nine patients (14.5%) died of P. aeruginosa bacteremia. Statistical analysis showed that non-survivors had significantly lower albumin levels than survivors (2.07 ± 0.62 vs 2.62 ± 0.65; P = 0.023). The non-survivors had significantly higher rates of ventilator use, history of heart disease, septic shock and lower rates of consultation with urological departments after diagnosis (P < 0.05). CONCLUSIONS: Patients with bacteremia complicating urinary infection by P. aeruginosa have a low death rate. Earlier intervention by urologists might improve patients' outcome. Lower albumin levels, ventilator use, history of heart disease and septic shock are factors associated with higher mortality rate.

Long-term efficacy of comprehensive multidisciplinary antibiotic stewardship programs centered on weekly prospective audit and feedback.

OBJECTIVE: To evaluate the long-term effects of comprehensive antibiotic stewardship programs (ASPs) on antibiotic use, antimicrobial-resistant bacteria, and clinical outcomes. DESIGN: Before-after study. SETTING: National university hospital with 934 beds. INTERVENTION: Implementation in March 2010 of a comprehensive ASPs including, among other strategies, weekly prospective audit and feedback with multidisciplinary collaboration. METHODS: The primary outcome was the use of antipseudomonal antibiotics as measured by the monthly mean days of therapy per 1000 patient days each year. Secondary outcomes included overall antibiotic use and that of each antibiotic class, susceptibility of Pseudomonas aeruginosa, the proportion of patients isolated methicillin-resistant Staphylococcus aureus (MRSA) among all patients isolated S. aureus, the incidence of MRSA, and the 30-day mortality attributable to bacteremia. RESULTS: The mean monthly use of antipseudomonal antibiotics significantly decreased in 2011 and after as compared with 2009. Susceptibility to levofloxacin was significantly increased from 2009 to 2016 (P = 0.01 for trend). Its susceptibility to other antibiotics remained over 84% and did not change significantly during the study period. The proportion of patients isolated MRSA and the incidence of MRSA decreased significantly from 2009 to 2016 (P < 0.001 and = 0.02 for trend, respectively). There were no significant changes in the 30-day mortality attributable to bacteremia during the study period (P = 0.57 for trend). CONCLUSION: The comprehensive ASPs had long-term efficacy for reducing the use of the targeted broad-spectrum antibiotics, maintaining the antibiotic susceptibility of P. aeruginosa, and decreasing the prevalence of MRSA, without adversely affecting clinical outcome.

Factors associated with residual gastroesophageal reflux disease symptoms in patients receiving proton pump inhibitor maintenance therapy.

AIM: To elucidate the factors associated with residual gastroesophageal reflux disease (GERD) symptoms in patients receiving proton pump inhibitor (PPI) maintenance therapy in clinical practice. METHODS: The study included 39 GERD patients receiving maintenance PPI therapy. Residual symptoms were assessed using the Frequency Scale for Symptoms of GERD (FSSG) questionnaire and the Gastrointestinal Symptom Rating Scale (GSRS). The relationships between the FSSG score and patient background factors, including the CYP2C19 genotype, were analyzed. RESULTS: The FSSG scores ranged from 1 to 28 points (median score: 7.5 points), and 19 patients (48.7%) had a score of 8 points or more. The patients' GSRS scores were significantly correlated with their FSSG scores (correlation coefficient = 0.47, P < 0.005). In erosive esophagitis patients, the FSSG scores of the CYP2C19 rapid metabolizers (RMs) were significantly higher than the scores of the poor metabolizers and intermediate metabolizers (total scores: 16.7 ± 8.6 vs 7.8 ± 5.4, P < 0.05; acid reflux-related symptom scores: 12 ± 1.9 vs 2.5 ± 0.8, P < 0.005). In contrast, the FSSG scores of the CYP2C19 RMs in the non-erosive reflux disease patients were significantly lower than those of the other patients (total scores: 5.5 ± 1.0 vs 11.8 ± 6.3, P < 0.05; dysmotility symptom-related scores: 1.0 ± 0.4 vs 6.0 ± 0.8, P < 0.01). CONCLUSION: Approximately half of the GERD patients receiving maintenance PPI therapy had residual symptoms associated with a lower quality of life, and the CYP2C19 genotype appeared to be associated with these residual symptoms.

Prostaglandin E1 reduces the keratinocyte toxicity of sorafenib by maintaining signal transducer and activator of transcription 3 (STAT3) activity and enhancing the cAMP response element binding protein (CREB) activity.

Hand-foot skin reaction (HFSR) is a common side effect of multiple tyrosine kinase inhibitors (mTKIs). HFSR can necessitate dose reductions or interruption of therapy owing to its negative effect on the quality of life. Therefore, effective use of mTKIs requires measures to prevent HFSR. We evaluated the effect of prostaglandin E1 (PGE1) on HFSR, because PGE1 is already used to treat bed sores and skin ulcers and has established angiogenic and antiproliferative effects in keratinocytes. We found that the pathogenesis of sorafenib-induced HFSR is characterized by a decrease in levels of a phosphorylated signal transducer and activator of transcription 3 (STAT3). We investigated the effect of PGE1 on the sorafenib-mediated reduction in phosphorylated STAT3 levels in HaCaT human epidermal keratinocytes. In cells treated with sorafenib, phosphorylated STAT3 levels decreased in a concentration-dependent manner, and this effect was blocked in cells treated with sorafenib and PGE1. Furthermore, the expression of phosphorylated STAT3, the antiapoptotic proteins myeloid cell leukemia-1 (Mcl-1) and survivin decreased in cells pretreated with an inhibitor of cAMP response element binding protein (CREB). Cell viability increased in cells treated with sorafenib and PGE1 compared with that in cells treated with sorafenib alone, and these effects were not observed in STAT3 knockdown HaCaT cells. Collectively, these findings indicate that PGE1 blocks the inhibitory effects of sorafenib on cell growth by maintaining the activity of STAT3 and enhancing the CREB activity. Therefore, PGE1 might represent an effective treatment for the prevention of sorafenib-induced HFSR.

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.

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.

Everolimus-induced human keratinocytes toxicity is mediated by STAT3 inhibition.

BACKGROUND: Mammalian 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. METHODS: We 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. RESULTS: The 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. CONCLUSIONS: These findings suggest that STAT3 activity may be a biomarker of everolimus-induced dermatological toxicity.

Disturbance of cerebellar synaptic maturation in mutant mice lacking BSRPs, a novel brain-specific receptor-like protein family.

By DNA cloning, we have identified the BSRP (brain-specific receptor-like proteins) family of three members in mammalian genomes. BSRPs were predominantly expressed in the soma and dendrites of neurons and localized in the endoplasmic reticulum (ER). Expression levels of BSRPs seemed to fluctuate greatly during postnatal cerebellar maturation. Triple-knockout mice lacking BSRP members exhibited motor discoordination, and Purkinje cells (PCs) were often innervated by multiple climbing fibers with different neuronal origins in the mutant cerebellum. Moreover, the phosphorylation levels of protein kinase Calpha (PKCalpha) were significantly downregulated in the mutant cerebellum. Because cerebellar maturation and plasticity require metabotropic glutamate receptor signaling and resulting PKC activation, BSRPs are likely involved in ER functions supporting PKCalpha activation in PCs.