Clinicomicrobiological risk factors for infective endocarditis in viridans group streptococci bacteraemia.

BACKGROUND: When to perform echocardiography to rule out infective endocarditis (IE) in patients with viridans group streptococci (VGS) bloodstream infections (BSIs) is unclear. OBJECTIVES: We aimed to identify independent risk factors for IE in patients with VGS BSI. METHODS: This retrospective study conducted at Seoul National University Hospital from January 2013 to December 2022 involved patients with VGS and nutritionally variant streptococcal BSI, excluding single positive blood cultures and polymicrobial BSI cases. Independent risk factors were identified by multivariate logistic regression and sensitivity analyses according to echocardiography results, VGS species or the inclusion of possible IE cases. RESULTS: Of 845 VGS BSI cases, 349 were analysed and 86 IE cases were identified (24.6%). In the multivariate analysis, heart valve disease [adjusted odds ratio (aOR), 14.14, 95% CI, 6.14-32.58; P < 0.001], persistent bacteraemia (aOR, 5.12, 95% CI, 2.03-12.94; P = 0.001), age (per year, aOR, 0.98; 95% CI, 0.96-1.00; P = 0.015), solid cancer (aOR, 0.26; 95% CI, 0.13-0.53; P < 0.001) and haematologic malignancy (aOR, 0.04; 95% CI, 0.01-0.41; P = 0.006) were independently associated with IE. Sensitivity analyses yielded consistent results; also, infection by a member of the mitis group was independent risk factor for IE (aOR, 6.50; 95% CI, 2.87-14.68; P < 0.001). CONCLUSIONS: Younger age, heart valve disease, persistent bacteraemia, absence of underlying malignancy and BSI by a member of the mitis group were independent risk factors for IE in patients with VGS BSI. Echocardiographic evaluation could be prudently considered based on these clinicomicrobiological risk factors.

Factors associated with sedentary behavior among community-dwelling breast cancer survivors aged 50 years or older.

Although increased sedentary behavior is associated with poor health outcomes among breast cancer survivors, the factors associated with high sedentary time in community-dwelling breast cancer survivors are unknown. This study aimed to identify factors associated with sedentary behavior in Korean community-dwelling breast cancer survivors aged ≥ 50 years. We included 205 breast cancer survivors from the Korea National Health and Nutrition Examination Survey. Total daily sedentary time was evaluated using questions from the Korean version of the Global Physical Activity Questionnaire. We used complex-sample multivariable-adjusted logistic regression analyses to analyze the associations between sociodemographic factors, medical factors, and health-related quality of life and high sedentary time (≥ 420 min/day). Among the Korean community-dwelling breast cancer survivors, 48.2% had a high daily sedentary time. Insufficient aerobic exercise (OR 2.29; 95% CI 1.12-4.69), diabetes (OR 3.37; 95% CI 1.22-9.33), and unemployed status (OR 2.29; 95% CI 1.05-5.02) were independently associated with high sedentary time after the adjustment for multiple sociodemographic and medical confounders. Participants with a low sedentary time (< 420 min/day) showed a significantly higher mean European Quality of Life 5-Dimensions (EQ-5D) index than those with a high sedentary time after adjusting for multiple confounders (0.89 ± 0.03 vs. 0.82 ± 0.04; P = 0.001). Among the EQ-5D dimensions, problems in mobility (OR 3.37; 95% CI 1.42-7.98) and pain/discomfort (OR 2.64; 95% CI 1.24-5.63) dimensions showed positive associations with high sedentary time. Middle- or older-aged breast cancer survivors with insufficient aerobic exercise, diabetes, unemployed status, and impaired quality of life are more likely to have a high sedentary time. Reducing sedentary behavior in this population requires a tailored approach that considers diverse sociodemographic, medical, and quality-of-life factors.

Differential association between physical activity behaviours and dynapenia by comorbid diseases in community-dwelling Korean older adults.

BACKGROUND: Physical activity (PA) behaviours and comorbid diseases are associated with muscle strength. However, the association between dynapenia and detailed PA behaviours, including participation in aerobic and resistance exercises and sedentary behaviour (SB), in relation to comorbid diseases has not yet been investigated. Using nationwide data, this study aimed to evaluate the independent association of dynapenia with detailed PA behaviour (participation in aerobic and resistance exercises and SB), and assess the differential associations of detailed PA behaviour with dynapenia according to comorbid diseases with prevalent sarcopenia. METHODS: A total of 7,558 community-dwelling older adults aged ≥ 65 years who were included in the Korea National Health and Nutrition Examination Survey from 2014 to 2019 were included in the present study. Cross-sectional associations between PA behaviours (participation in aerobic exercise, participation in resistance exercise, and SB) and dynapenia were analysed using complex-sample multivariable-adjusted logistic regression models according to the type of comorbid disease (cardiovascular disease [CVD], diabetes mellitus [DM], and chronic lung disease [CLD]). RESULTS: Sufficient aerobic exercise, sufficient resistance exercise, and low sedentary time of < 420 min/day showed independent negative associations with dynapenia (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.60-0.83; OR, 0.54; 95% CI, 0.42-0.69; and OR, 0.84; 95% CI, 0.72-0.97, respectively). Among the participants with CVD or CLD, the associations of sufficient resistance exercise (OR, 0.46; 95% CI, 0.26-0.82 and OR, 0.51; 95% CI, 0.35-0.75 for CVD and CLD, respectively) and low sedentary time (OR, 0.66; 95% CI, 0.45-0.98 and OR, 0.71; 95% CI, 0.55-0.93 for CVD and CLD, respectively) with dynapenia were significant, whereas the association of sufficient aerobic exercise with dynapenia was insignificant. Meanwhile, in participants with DM, sufficient aerobic exercise (OR, 0.70; 95% CI, 0.52-0.94) and sufficient resistance exercise (OR, 0.45; 95% CI, 0.29-0.70) were independently associated with dynapenia, whereas no association between SB and dynapenia was found. CONCLUSION: We observed an independent inverse association between PA behaviours and dynapenia. Disease-specific associations between each PA behaviour (sufficient aerobic exercise, sufficient resistance exercise, and low sedentary time) and dynapenia differed in the older adults. Therefore, these differences should be acknowledged during interventions for this population.

Prosthetic valve endocarditis caused by Campylobacter fetus: a case report and literature review.

Campylobacter fetus is a Gram-negative bacillus typically associated with bacteremia in immunocompromised patients. Prosthetic valve endocarditis (PVE) is a serious complication of prosthetic valve surgery, with a high mortality rate if not treated promptly. We present a rare case of PVE caused by C. fetus. A man in his mid-60s presented to the Emergency Department with a fever and showed elevated C-reactive protein concentrations. He had prosthetic mitral and aortic valve replacement surgery 15 years previously. Gram-negative rods were detected in a blood culture. These rods were identified as C. fetus using matrix-assisted laser desorption ionization time-of-flight mass spectrometry and confirmed by 16S rRNA sequencing. The patient was treated with gentamicin and imipenem, and underwent valve replacement surgery. C. fetus was isolated in a left atrial appendage swab obtained during the surgery. Follow-up blood cultures were negative after treatment. However, after a cardiac arrest event, the patient's general condition deteriorated, and he died. To the best of our knowledge, this is the first case of PVE caused by C. fetus in Korea and the second fatality to date. This case highlights the importance of considering C. fetus as a potential cause of PVE, even in patients without known risk factors.

A pilot randomized study for optimal red cell transfusion in acute myeloid leukemia patients with intensive chemotherapy.

BACKGROUND: Although blood transfusion is fundamental throughout the course of hematologic malignancies, acute myeloid leukemia (AML) patients requiring intensive chemotherapy are left at the edges of patient blood management programs because current guidelines do not have established recommendations for red blood cell (RBC) transfusion threshold in patients treated for hematological disorders with anemia and accompanied severe thrombocytopenia. To provide answers for the trigger and doses of ideal RBC transfusion in such situation, we conducted this prospective randomized trial. MATERIALS AND METHODS: Newly diagnosed non-acute promyelocytic AML patients undergoing chemotherapy were considered eligible for enrollment. Patients were randomized into 4 groups using a 2 by 2 factorial design, according to the RBC transfusion trigger (hemoglobin [Hb], 7 vs 8 g/dL) and the number of units per transfusion episode (quantity, single vs double-unit). RESULTS: Initially 91 patients were randomized into 4 groups, but the protocol adherence rate was 90.1%. Hb trigger did not affect the amount of RBC transfusion required during treatment. Patients receiving RBC transfusion at Hb <7 g/dL used a median of 4 units of RBC (range 0-12), and those receiving transfusion at Hb <8 g/dL also used a median of 4 units of RBC (range 0-24) (p=0.305). The number of RBC units per transfusion did not affect the total amount of RBC transfusion required during treatment. AML treatment outcomes and bleeding events did not differ across the 4 groups. DISCUSSION: This study demonstrated the feasibility for restrictive RBC transfusion (Hb <7 g/dL, RBC 1 unit) in AML patients undergoing chemotherapy, regardless of chemotherapy intensity.

Anti-inflammatory effect and metabolic mechanism of BS012, a mixture of Asarum sieboldii, Platycodon grandiflorum, and Cinnamomum cassia extracts, on atopic dermatitis in vivo and in vitro.

BACKGROUND: Atopic dermatitis (AD) is a chronic, relapsing skin disease accompanied by itchy and dry skin. AD is caused by complex interactions between innate and adaptive immune response. AD treatment include glucocorticoids and immunosuppressants. However, long-term treatment can have serious side effects. Thus, an effective AD treatment with fewer side effects is required. Natural materials, including herbal medicines, have potential applications. PURPOSE: This study evaluated the in vivo and in vitro therapeutic effects of BS012, a mixture of Asarum sieboldii, Platycodon grandiflorum, and Cinnamomum cassia extracts, on AD and investigated the underlying metabolic mechanisms. METHODS: The anti-inflammatory effects of BS012 were assessed using a mouse model of AD induced by 1­chloro-2,4-dinitrobenzene (DNCB) and in tumor necrosis factor-alpha/interferon-gamma (TNF-α/IFN-γ) stimulated normal human epidermal keratinocytes (NHEKs). In DNCB-induced mice, total dermatitis score, histopathological analysis, and immune cell factors were assessed to evaluate the anti-atopic activity. In TNF-α/IFN-γ-stimulated NHEKs, pro-inflammatory cytokines, chemokines, and related signaling pathways were investigated. Serum and intracellular metabolomics were performed to identify the metabolic mechanism underlying the therapeutic effects of BS012 treatment. RESULTS: In DNCB-induced mice, BS012 showed potent anti-atopic activity, including reducing AD-like skin lesions and inhibiting the expression of Th2 cytokines and thymic stromal lymphopoietin. In TNF-α/IFN-γ-stimulated keratinocytes, BS012 dose-dependently inhibited the expression of pro-inflammatory cytokines and chemokines by blocking nuclear factor-kappa B and signal transducer and activator of transcription signaling pathways. Serum metabolic profiles of mice revealed significant changes in lipid metabolism related to inflammation in AD. Intracellular metabolome analysis revealed that BS012 treatment affected the metabolism associated with inflammation, skin barrier function, and lipid organization of the stratum corneum. CONCLUSION: BS012 exerts anti-atopic activity by reducing the Th2-specific inflammatory response and improving skin barrier function in AD in vivo and in vitro. These effects are mainly related to the inhibition of inflammation and recovery of metabolic imbalance in lipid organization. BS012, a novel combination with strong activity in suppressing the Th2-immune response, could be a potential alternative for AD treatment. Furthermore, the metabolic mechanism in vivo and in vitro using a metabolomics approach will provide crucial information for the development of natural products for AD treatment.

Apocynin abrogates methotrexate-induced nephrotoxicity: role of TLR4/NF-κB-p65/p38-MAPK, IL-6/STAT-3, PPAR-γ, and SIRT1/FOXO3 signaling pathways.

The present study was designed to evaluate the potential renoprotective impacts of apocynin (APC) against nephrotoxicity induced by methotrexate (MTX) administration. To fulfill this aim, rats were allocated into four groups: control; APC (100 mg/kg/day; orally); MTX (20 mg/kg; single intraperitoneal dose at the end of the 5th day of the experiment); and APC +MTX (APC was given orally for 5 days before and 5 days after induction of renal toxicity by MTX). On the 11th day, samples were collected to estimate kidney function biomarkers, oxidative stress, pro-inflammatory cytokines, and other molecular targets. Compared to the MTX control group, treatment with APC significantly decreased urea, creatinine, and KIM-1 levels and improved kidney histological alterations. Furthermore, APC restored oxidant/antioxidant balance, as evidenced by a remarkable alleviation of MDA, GSH, SOD, and MPO levels. Additionally, the iNOS, NO, p-NF-κB-p65, Ace-NF-κB-p65, TLR4, p-p38-MAPK, p-JAK1, and p-STAT-3 expressions were reduced, while the IκBα, PPAR-γ, SIRT1, and FOXO3 expressions were significantly increased. In NRK-52E cells, MTX-induced cytotoxicity was protected by APC in a concentration-dependent manner. In addition, increased expression of p-STAT-3 and p-JAK1/2 levels were reduced in MTX-treated NRK-52E cells by APC. The in vitro experiments revealed that APC-protected MTX-mediated renal tubular epithelial cells were damaged by inhibiting the JAK/STAT3 pathway. Besides, our in vivo and in vitro results were confirmed by predicting computational pharmacology results using molecular docking and network pharmacology analysis. In conclusion, our findings proved that APC could be a good candidate for MTX-induced renal damage due to its strong antioxidative and anti-inflammatory bioactivities.

RecQ dysfunction contributes to social and depressive-like behavior and affects aldolase activity in mice.

RecQ helicase family proteins play vital roles in maintaining genome stability, including DNA replication, recombination, and DNA repair. In human cells, there are five RecQ helicases: RECQL1, Bloom syndrome (BLM), Werner syndrome (WRN), RECQL4, and RECQL5. Dysfunction or absence of RecQ proteins is associated with genetic disorders, tumorigenesis, premature aging, and neurodegeneration. The biochemical and biological roles of RecQ helicases are rather well established, however, there is no systematic study comparing the behavioral changes among various RecQ-deficient mice including consequences of exposure to DNA damage. Here, we investigated the effects of ionizing irradiation (IR) on three RecQ-deficient mouse models (RecQ1, WRN and RecQ4). We find abnormal cognitive behavior in RecQ-deficient mice in the absence of IR. Interestingly, RecQ dysfunction impairs social ability and induces depressive-like behavior in mice after a single exposure to IR, suggesting that RecQ proteins play roles in mood and cognition behavior. Further, transcriptomic and metabolomic analyses revealed significant alterations in RecQ-deficient mice, especially after IR exposure. In particular, pathways related to neuronal and microglial functions, DNA damage repair, cell cycle, and reactive oxygen responses were downregulated in the RecQ4 and WRN mice. In addition, increased DNA damage responses were found in RecQ-deficient mice. Notably, two genes, Aldolase Fructose-Bisphosphate B (Aldob) and NADPH Oxidase 4 (Nox4), were differentially expressed in RecQ-deficient mice. Our findings suggest that RecQ dysfunction contributes to social and depressive-like behaviors in mice, and that aldolase activity may be associated with these changes, representing a potential therapeutic target.

Analysis of clinical and genomic profiles of therapy-related myeloid neoplasm in Korea.

BACKGROUND: Therapy-related myeloid neoplasm (T-MN) rarely occurs among cancer survivors, and was characterized by poor prognosis. T-MN has germline predisposition in a considerable proportion. Here, clinical characteristics and germline/somatic variant profiles in T-MN patients were investigated, and the findings were compared with those of previous studies. METHODS: A review of medical records, cytogenetic study, targeted sequencing by next-generation sequencing, and survival analysis were performed on 53 patients with T-MN at a single institution in Korea. RESULTS: The patients were relatively younger compared to T-MN patients in other studies. Our T-MN patients showed a high frequency of complex karyotypes, -5/del(5q), and -7/del(7q), which was similar to the Japanese study group but higher than the Australian study group. The most common primary disease was non-Hodgkin lymphoma, followed by breast cancer. The detailed distributions of primary diseases were different across study groups. Seven patients (13.2%) harbored deleterious presumed/potential germline variants in cancer predisposition genes (CPG) such as BRIP1, CEBPA, DDX41, FANCM, NBN, NF1, and RUNX1. In the somatic variant profile, TP53 was the most frequently mutated gene, which was consistent with the previous studies about T-MN. However, the somatic variant frequency in our study group was lower than in other studies. Adverse factors for overall survival were male sex, older age, history of previous radiotherapy, previous longer cytotoxic therapy, and -5/del(5q). CONCLUSION: The findings of our study corroborate important information about T-MN patients. As well as a considerable predisposition to CPG, the clinical characteristics and somatic variant profile showed distinctive patterns. Germline variant testing should be recommended for T-MN patients. If the T-MN patients harbor pathogenic germline variants, the family members for stem cell donation should be screened for carrier status through germline variant testing to avoid donor-derived myeloid neoplasm. For the prediction of the prognosis in T-MN patients, sex, age, past treatment history, and cytogenetic findings can be considered.

Pyruvate Kinase M2: A New Biomarker for the Early Detection of Diabetes-Induced Nephropathy.

Diabetic nephropathy (DN) is a common complication of diabetes. DN progresses to end-stage renal disease, which has a high mortality rate. Current research is focused on identifying non-invasive potential biomarkers in the early stage of DN. We previously indicated that pyruvate kinase M2 (PKM2) is excreted in the urine of rats after cisplatin-induced acute kidney injury (AKI). However, it has not been reported whether PKM2 can be used as a biomarker to diagnose DN. Therefore, we try to compare whether the protein PKM2 can be detected in the urine samples from diabetic patients as shown in the results of DN models. In this study, high-fat diet (HFD)-induced Zucker diabetic fatty (ZDF) rats were used for DN phenotyping. After 19 weeks of receiving a HFD, the DN model's blood glucose, blood urea nitrogen, and serum creatinine levels were significantly increased; severe tubular and glomerular damages were also noted. The following protein-based biomarkers were increased in the urine of these models: kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and PKM2. PKM2 had the earliest detection rate. In the urine samples of patients, PKM2 protein was highly detected in the urine of diabetic patients but was not excreted in the urine of normal subjects. Therefore, PKM2 was selected as the new biomarker for the early diagnosis of DN. Our results reflect current knowledge on the role of PKM2 in DN.

Low-dose Pimecrolimus, an FDA-approved Calcineurin Inhibitor, Sensitizes Drug-resistant Cancer Cells via Strong P-gp Inhibition.

BACKGROUND/AIM: Co-treatment with calcineurin inhibitors, such as tacrolimus and cyclosporin A, can sensitize chemotherapy-resistant cancer cells with P-glycoprotein (P-gp)-over-expression. Pimecrolimus (PIME) is a clinically available calcineurin inhibitor with a structure similar to that of tacrolimus. Whether PIME can sensitize P-gp-over-expressing resistant cancer cells remains unclear. MATERIALS AND METHODS: Cell viability assay, annexin V analyses, cellular morphology and density observation with a microscope, western-blotting, fluorescence-activated cell sorting (FACS), and analysis for P-gp inhibitory activity were performed to investigate the mechanism of action. RESULTS: PIME exhibited strong cytotoxicity to vincristine (VIC)-treated drug-resistant cell lines (KBV20C and MCF-7/ADR) over-expressing P-gp. Co-treatment with VIC and PIME increased apoptosis and down-regulated the ERK signaling pathway, resulting in G2 arrest. PIME could be co-administered with vinorelbine or eribulin to sensitize resistant KBV20C or MCF-7/ADR cancer cells. Moreover, PIME strongly inhibited the efflux of both rhodamine 123 and calcein-AM substrates through P-gp after 4 h of treatment, indicating that VIC+PIME sensitized cancer cells by inhibiting VIC efflux via direct PIME binding to P-gp. Low doses of PIME, tacrolimus, and cyclosporin A showed similar sensitizing efficiencies in resistant KBV20C cells. These drugs showed similar P-gp inhibitory activities using both rhodamine 123 and calcein-AM substrates, suggesting that calcineurin inhibitors generally have strong P-gp inhibitory activities that sensitize drug-resistant cancer cells with P-gp over-expression. CONCLUSION: PIME, currently used in clinics, can be repositioned for treating patients with P-gp-over-expressing resistant cancer (stem) cells.

Effect of chlorhexidine Mouthrinse on prevention of microbial contamination during EBUS-TBNA: a randomized controlled trial.

BACKGROUND: Although endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure, fatal infectious complications have been reported. However, adequate preventive strategies have not been determined. We aimed to investigate the effect of chlorhexidine mouthrinse on the prevention of microbial contamination during EBUS-TBNA. METHODS: In this single-center, assessor-blinded, parallel-group randomized controlled trial, we randomly assigned adult participants undergoing EBUS-TBNA using a convex probe to gargle for 1 minute with 100 mL of 0.12% chlorhexidine gluconate before EBUS-TBNA or to receive usual care (no chlorhexidine mouthrinse). Aspiration needle wash samples were collected immediately after completion of EBUS-TBNA by instilling sterile saline into the used needle. The primary outcome was colony forming unit (CFU) counts per mL of needle wash samples in aerobic cultures. Secondary outcomes were CFU counts per mL of needle wash samples in anaerobic cultures, fever within 24 hours after EBUS-TBNA, and infectious complications within 4 weeks after EBUS-TBNA. RESULTS: From January 2021 to June 2021, 106 patients received either chlorhexidine mouthrinse (n = 51) or usual care (n = 55). The median CFU counts of needle wash samples in aerobic cultures were not significantly different in the two groups (10 CFU/mL vs 20 CFU/mL; P = 0.70). There were no significant differences between the groups regarding secondary outcomes, including median CFU counts in anaerobic cultures (P = 0.41) and fever within 24 hours after EBUS-TBNA (11.8% vs 5.6%, P = 0.31). There were no infectious complications within 4 weeks in both groups. CONCLUSIONS: Chlorhexidine mouthrinse did not reduce CFU counts in needle wash samples of EBUS-TBNA. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04718922 . Registered on 22/01/2021.

Novel THPO variant in hereditary thrombocytopenia: A potential candidate variant for predisposition to myeloid neoplasm.

Hereditary thrombocytopenia is a heterogeneous group of congenital disorders with a wide range of symptoms depending on the severity of platelet dysfunction or thrombocytopenia. Because of its clinical phenotypes and the bone marrow morphology associated with this condition, hereditary thrombocytopenia can be misdiagnosed as primary immune thrombocytopenia and myelodysplastic syndrome. Therefore, genetic evidence is necessary for the accurate diagnosis of hereditary thrombocytopenia. Refractory cytopenia of childhood is a subgroup of myelodysplastic syndrome that was added to the World Health Organization classification in 2008. To investigate the germline and somatic variants associated with refractory cytopenia of childhood, we performed targeted multigene sequencing in three patients with refractory cytopenia of childhood. Of the three patients, one progressed from megakaryocytic hypoplasia with thrombocytopenia, and targeted multigene sequencing revealed THPO variants in this patient and his sister. We propose that the monoallelic deletion of THPO is a potential candidate for germline predisposition to myeloid malignancy.

Terconazole, an Azole Antifungal Drug, Increases Cytotoxicity in Antimitotic Drug-Treated Resistant Cancer Cells with Substrate-Specific P-gp Inhibitory Activity.

Azole antifungal drugs have been shown to enhance the cytotoxicity of antimitotic drugs in P-glycoprotein (P-gp)-overexpressing-resistant cancer cells. Herein, we examined two azole antifungal drugs, terconazole (TCZ) and butoconazole (BTZ), previously unexplored in resistant cancers. We found that both TCZ and BTZ increased cytotoxicity in vincristine (VIC)-treated P-gp-overexpressing drug-resistant KBV20C cancer cells. Following detailed analysis, low-dose VIC + TCZ exerted higher cytotoxicity than co-treatment with VIC + BTZ. Furthermore, we found that VIC + TCZ could increase apoptosis and induce G2 arrest. Additionally, low-dose TCZ could be combined with various antimitotic drugs to increase their cytotoxicity in P-gp-overexpressing antimitotic drug-resistant cancer cells. Moreover, TCZ exhibited P-gp inhibitory activity, suggesting that the inhibitory activity of P-gp plays a role in sensitization afforded by VIC + TCZ co-treatment. We also evaluated the cytotoxicity of 12 azole antifungal drugs at low doses in drug-resistant cancer cells. VIC + TCZ, VIC + itraconazole, and VIC + posaconazole exhibited the strongest cytotoxicity in P-gp-overexpressing KBV20C and MCF-7/ADR-resistant cancer cells. These drugs exerted robust P-gp inhibitory activity, accompanied by calcein-AM substrate efflux. Given that azole antifungal drugs have long been used in clinics, our results, which reposition azole antifungal drugs for treating P-gp-overexpressing-resistant cancer, could be employed to treat patients with drug-resistant cancer rapidly.

Combination Treatment Using Pyruvate Kinase M2 Inhibitors for the Sensitization of High Density Triple-negative Breast Cancer Cells.

BACKGROUND/AIM: Few studies have examined the correlation between pyruvate kinase M2 (PKM2) overexpression and triple-negative breast cancer (TNBC). TNBC is considered incurable with the currently available treatments, highlighting the need for alternative therapeutic targets. MATERIALS AND METHODS: PKM2 expression was examined immunohistochemically in human breast tumor samples. Furthermore, we studied the effect of three PKM2 inhibitors (gliotoxin, shikonin, and compound 3K) in the MDA-MB-231 TNBC cell line. RESULTS: PKM2 overexpression correlates with TNBC. Interestingly, most TNBC tissues showed increased levels of PKM2 compared to those of receptor-positive breast cancer tissues. This suggests that PKM2 overexpression is an important factor in the development of TNBC. MDA-MB-231 TNBC cells are resistant to anticancer drugs, such as vincristine (VIC) compared to other cancer cells. We found that the recently developed PKM2 inhibitor gliotoxin sensitized MDA-MB-231 cells at a relatively low dose to the same extent as the known PKM2 inhibitor shikonin, suggesting that PKM2 inhibitors could be an effective treatment for TNBC. Detailed sensitization mechanisms were also analyzed. Both gliotoxin and shikonin highly increased late apoptosis in MDA-MB-231 cells, as revealed by annexin V staining. However, MDA-MB-231 cells with high cellular density inhibited the sensitizing effect of PKM2 inhibitors; therefore, we investigated ways to overcome this inhibitory effect. We found that gliotoxin+shikonin co-treatment highly increased toxicity in MDA-MB-231 cells with high density, whereas either VIC+gliotoxin or VIC+shikonin were not effective. Thus, combination therapy with various PKM2 inhibitors may be more effective than combination therapy with anticancer drugs. Gliotoxin+shikonin co-treatment did not increase S or G2 arrest in cells, suggesting that the co-treatment showed a high increase in apoptosis without S or G2 arrest. We confirmed that another recently developed PKM2 inhibitor compound 3K had similar mechanisms of sensitizing MDA-MB-231 cells, suggesting that PKM2 inhibitors have similar sensitization mechanisms in TNBC. CONCLUSION: PKM2 is a regulator of the oncogenic function of TNBC, and combination therapy with various PKM2 inhibitors may be effective for high-density TNBC. Targeting PKM2 in TNBC lays the foundation for the development of PKM2 inhibitors as promising anti-TNBC agents.

Glycolytic Metabolic Remodeling by the Truncate of Glioma-Associated Oncogene Homolog 1 in Triple-Negative Breast Cancer Cells.

Hedgehog (Hh) signaling pathway plays an essential role in embryonic development, tissue regeneration, and stem cell renewal. In particular, terminal effectors of the Hh signaling pathway are associated with the regulation of glioma-associated oncogene homolog 1 (GLI1) transcription factors. Overexpression of GLI1 is closely associated with poor prognosis in breast cancer. The Hh-GLI1 signaling pathway is activated and participates in the tumorigenesis and progression of breast cancer, especially in the aggressive subtype of triple-negative breast cancer (TNBC). However, the role of GLI1 in regulating TNBC metabolism remains unclear. This study aimed to explore the functional role of GLI1 in glycolytic metabolism in TNBC. Immunohistochemical analysis of GLI1 expression in a tissue microarray revealed significant correlations between GLI1 expression and advanced tumor stage and grade. GLI1 expression levels were drastically increased in MDA-MB-231 cells compared to those in other cell lines. Inhibition of GLI1 expression using GLI1 small interfering RNA (siRNA) in MDA-MB-231 cells resulted in a significant reduction in cell proliferation and induced cell cycle arrest at the G1 phase. Furthermore, GLI1 downregulation significantly reduced the expression of glycolysis-regulated proteins. GLI1 knockdown resulted in reduced glycolytic rates and extracellular lactate levels. Moreover, metabolic stress after GLI1 knockdown activated the energy sensor, adenosine monophosphate-activated protein kinase, which subsequently resulted in autophagy induction. In conclusion, this study indicates that targeting GLI1 reprograms the tumor glucose metabolism to suppress breast cancer cell growth and proliferation.

Heterogeneous genetic landscape of congenital neutropenia in Korean patients revealed by whole exome sequencing: genetic, phenotypic and histologic correlations.

Congenital neutropenia (CN) is a hematological disease heterogeneous in its genetic, phenotypic and histologic aspects. We aimed to identify the genetic etiology of Korean CN patients in the context of bone marrow (BM) histology and clinical phenotype. Whole-exome sequencing (WES) or targeted sequencing was performed on the BM or peripheral blood specimens of 16 patients diagnosed with CN based on BM exam from 2009 to 2018. Absolute count of myeloperoxidase (MPO)-positive cells was calculated using ImageJ software. Semi-quantitation of MPO-positive cells in BM sections was performed by MPO grading (grades 0-3). Comprehensive retrospective review on real-world data of 345 pediatric patients with neutropenia including 16 patients in this study during the same period was performed. Seven disease-causing variants were identified in ELANE, G6PC3 and CXCR4 in 7 patients. A novel homozygous G6PC3 variant (K72fs) of which the mechanism was copy-neutral loss of heterozygosity was detected in two brothers. A low myeloid-to-erythroid ratio (0.5-1.5) was consistently observed in patients with ELANE mutations, while MPO-positive cells (40%-50%) with MPO grade 1 or 2 were detected in myelokathexis caused by G6PC3 and CXCR4 mutations. Meanwhile, disease-causing variants were detected in ELANE, TAZ and SLC37A4 in 5 patients by retrospective review of medical records. Our results suggest that following the immunological study and BM exam, WES or an expanded next generation sequencing panel that covers genes related to immunodeficiency and other inherited bone marrow failures as well as CN is recommended for neutropenia patient diagnosis.

JAK2 Inhibitor, Fedratinib, Inhibits P-gp Activity and Co-Treatment Induces Cytotoxicity in Antimitotic Drug-Treated P-gp Overexpressing Resistant KBV20C Cancer Cells.

P-glycoprotein (P-gp) overexpression is one of the major mechanisms of multidrug resistance (MDR). Previously, co-treatment with Janus kinase 2 (JAK2) inhibitors sensitized P-gp-overexpressing drug-resistant cancer cells. In this study, we assessed the cytotoxic effects of JAK2 inhibitor, fedratinib, on drug-resistant KBV20C cancer cells. We found that co-treatment with fedratinib at low doses induced cytotoxicity in KBV20C cells treated with vincristine (VIC). However, fedratinib-induced cytotoxicity was little effect on VIC-treated sensitive KB parent cells, suggesting that these effects are specific to resistant cancer cells. Fluorescence-activated cell sorting (FACS), Western blotting, and annexin V analyses were used to further investigate fedratinib's mechanism of action in VIC-treated KBV20C cells. We found that fedratinib reduced cell viability, increased G2 arrest, and upregulated apoptosis when used as a co-treatment with VIC. G2 phase arrest and apoptosis in VIC-fedratinib-co-treated cells resulted from the upregulation of p21 and the DNA damaging marker pH2AX. Compared with dimethyl sulfoxide (DMSO)-treated cells, fedratinib-treated KBV20C cells showed two-fold higher P-gp-inhibitory activity, indicating that VIC-fedratinib sensitization is dependent on the activity of fedratinib. Similar to VIC, fedratinib co-treatment with other antimitotic drugs (i.e., eribulin, vinorelbine, and vinblastine) showed increased cytotoxicity in KBV20C cells. Furthermore, VIC-fedratinib had similar cytotoxic effects to co-treatment with other JAK2 inhibitors (i.e., VIC-CEP-33779 or VIC-NVP-BSK805) at the same dose; similar cytotoxic mechanisms (i.e., early apoptosis) were observed between treatments, suggesting that co-treatment with JAK2 inhibitors is generally cytotoxic to P-gp-overexpressing resistant cancer cells. Given that fedratinib is FDA-approved, our findings support its application in the co-treatment of P-gp-overexpressing cancer patients showing MDR.

Co-treatment of Low Dose Pacritinib, a Phase III Jak2 Inhibitor, Greatly Increases Apoptosis of P-gp Over-expressing Cancer Cells With Multidrug Resistance.

BACKGROUND/AIM: The over-expression of P-glycoprotein (P-gp) is a major mechanism underlying multidrug resistance (MDR). Co-treatment with Janus kinase 2 (Jak2) inhibitors sensitizes P-gp-over-expressing drug-resistant cancer cells. In this study, we evaluated pacritinib, a Jak2 inhibitor currently in phase III clinical trials. MATERIALS AND METHODS: Microscopic observation, cell viability assay, colony forming assay, rhodamine uptake tests, annexin V analyses, fluorescence-activated cell sorting (FACS), and western-blot analysis were performed to further investigate the mechanism of action. RESULTS: We found that pacritinib reduced cell viability, induced G2 arrest, and upregulated early apoptosis when administered to P-gp-over-expressing resistant KBV20C cells with vincristine (VIC). Moreover, apoptosis and G2 arrest in VIC-pacritinib-treated cells were involved in the upregulation of pH2AX expression. Pacritinib had an approximately 2-fold higher P-gp-inhibitory activity than the dimethyl sulfoxide (DMSO)-treated control, indicating that VIC-pacritinib sensitization involves the P-gp-inhibitory effects of pacritinib. Similar to VIC, other antimitotic drugs (vinorelbine, vinblastine, and eribulin) could also sensitize against KBV20C cells by co-treatment with pacritinib. Furthermore, comparison of pacritinib with previously characterized Jak2 inhibitors revealed that the VIC-pacritinib combination had sensitization effects similar to those of VIC- CEP-33779 or VIC-NVP-BSK805 combinations at lower doses in KBV20C cells. Generally, Jak2 inhibitor and VIC co-treatment sensitized P-gp-over-expressing resistant cancer cells by inducing early apoptosis. CONCLUSION: Collectively, pacritinib, induced G2 arrest, reduced cell viability, had high P-gp inhibitory activity, and upregulated the expression of pH2AX when used in combination with VIC. As pacritinib is a Jak2 inhibitor currently in phase III clinical trials, our findings may facilitate the application of this co-treatment in patients with MDR cancer.