ASXL2 promotes proliferation of breast cancer cells by linking ERα to histone methylation.

Estrogen receptor alpha (ERα) has a pivotal role in breast carcinogenesis by associating with various cellular factors. Selective expression of additional sex comb-like 2 (ASXL2) in ERα-positive breast cancer cells prompted us to investigate its role in chromatin modification required for ERα activation and breast carcinogenesis. Here, we observed that ASXL2 interacts with ligand E2-bound ERα and mediates ERα activation. Chromatin immunoprecipitation-sequencing analysis supports a positive role of ASXL2 at ERα target gene promoters. ASXL2 forms a complex with histone methylation modifiers including LSD1, UTX and MLL2, which all are recruited to the E2-responsive genes via ASXL2 and regulate methylations at histone H3 lysine 4, 9 and 27. The preferential binding of the PHD finger of ASXL2 to the dimethylated H3 lysine 4 may account for its requirement for ERα activation. On ASXL2 depletion, the proliferative potential of MCF7 cells and tumor size of xenograft mice decreased. Together with our finding on the higher ASXL2 expression in ERα-positive patients, we propose that ASXL2 could be a novel prognostic marker in breast cancer.

Efficacy and safety of hepatitis A vaccination in kidney transplant recipients.

BACKGROUND: In recent years, symptomatic hepatitis A virus (HAV) infection has been reported with increasing frequency in Korea. Therefore, HAV vaccination should be considered in kidney transplant recipients (KTRs). The study investigated the efficacy and safety of HAV vaccination in KTRs under modern triple immunosuppressive agents. METHODS: We evaluated the seroprevalence of anti-HAV immunoglobulin-G (IgG) in KTRs who had visited the Seoul National University Hospital from March 2011 to August 2012. Seronegative patients were immunized with 2 doses of HAV vaccine at a 6-month interval. Seroconversion of anti-HAV IgG was determined 1 month after the second vaccine dose, and adverse effects were monitored after each vaccination. RESULTS: Among a total 416 KTRs who were screened, 338 (81.2%) patients were seropositive for anti-HAV IgG. However, among patients who were under 40 years of age, only 31.8% were seropositive. Fifty-two seronegative recipients (mean age 34.1 years, 71.2% male) had received 2 doses of vaccine, and only 14 of these patients (26.9%) showed seroconversion. Vaccine responders had lower serum creatinine (1.19 ± 0.24 vs. 1.45 ± 0.49 mg/dL, P = 0.013), higher plasma hemoglobin levels (14.4 ± 1.9 vs. 12.8 ± 1.8 g/dL, P = 0.006), and had lower tacrolimus use than cyclosporine use (57.1% vs. 84.2%, P = 0.040) compared with non-responders. Responders had a tendency of taking lower dose of prednisolone (3.5 ± 1.6 vs. 4.3 ± 1.2 mg/day, P = 0.076), and having fewer infection events (14.3 vs. 40.5%, P = 0.076). Multivariate analysis indicated that higher hemoglobin levels and lower serum creatinine levels were significant prognostic factors for seroconversion. Overall, the vaccine was well tolerated in all patients. CONCLUSION: HAV IgG screening is necessary for KTRs, especially young recipients. HAV vaccination was safe in KTRs; however, poor response to HAV vaccination makes it important to identify seronegative patients as early as possible and vaccinate them before end-stage renal disease occurs.

Initial report of the Korean Organ Transplant Registry: the first report of national kidney transplantation data.

PURPOSE: A national organ transplant registry is an indispensable organizational requirement for patient care, research, and planning. Even though the Korean Network for Organ Sharing (KONOS) has established a database for a waiting list, organ allocation, and incidence of organ transplantation since 2000, an integrated registry including post-transplantation data is needed for better understanding of organ transplantation. Recently, the Korean Society for Transplantation (KST) and the Korean Center for Disease Control (KCDC) designed a web-based organ transplant registry, named the Korean Organ Transplant Registry (KOTRY). As an initial project of KOTRY, we retrospectively analyzed kidney transplantations (KTs) performed in 2009 and 2010. METHODS: A total of 2292 KTs (91.9%) from 46 hospitals (80.7%) were collected and analyzed. Ninety-five elements related to KT were selected and analyzed. RESULTS: Proportions of male recipients and retransplantations were 58.4% and 7.1%, respectively. Even though glomerulonephritis was the most common cause of end-stage renal disease (ESRD) (28.4%), the number of diabetic nephropathy cases was increasing. The living donor (LD) to deceased donor (DD) ratio was 1.69:1. Because of a serious organ shortage in Korea, DD kidneys with a low initial estimated glomerular filtration rate (eGFR) of <45 mL/min/1.73 m(2) (21.2%) and expanded criteria donors (ECDs; 18.3%) are frequently used. Other noticeable findings are the increasing number of wife donors and ABO-incompatible (ABOi) transplants for O(+) recipients. CONCLUSIONS: The epidemiological profile of transplantation is different from country to country. The number of organ transplantations in East Asian countries is rapidly growing, however, there are few epidemiological data about this region in the literature. With the establishment of KOTRY, it was possible to present the first nationwide epidemiological data of Korean KTs.

Utility of QuantiFERON-TB assay for prediction of tuberculosis development in kidney transplant patients in an intermediate-tuberculosis-burden country: lack of evidence for enhanced prediction for short-term tuberculosis development.

INTRODUCTION: Although a latent tuberculosis (TB) infection is a risk factor for active TB, the diagnosis of latent TB infection is difficult in end-stage renal disease patients. PATIENTS AND METHODS: We retrospectively compared the results of the QuantiFERON-TB (QFT) test and the tuberculin skin test in patients on the waiting list for kidney transplantation (KT), and investigated whether the QFT test can predict TB development in KT recipients in an intermediate-TB-burden country. RESULTS: The incidence of post-KT TB was 283 cases/100,000 patient-years among 1274 KT recipients at the Seoul National University Hospital. The overall standardized incidence ratio of TB was 4.358 compared with the general population. A past history of TB infection, smoking history, myocardial infarction after KT, and pneumocystis infection were significant predictors of subsequent TB development (adjusted odds ratios were 3.618, 2.959, 9.993, and 5.708, respectively). Among the 129 recipients who had the QFT test, 42 patients (32.5%) had positive a QFT. At a median follow-up of 8.4 ± 6.8 months, 1 patient with positive QFT results developed TB after KT, and 1 of the 87 patients with negative QFT results developed TB after KT. In both of these 2 cases, active TB developed despite isoniazid prophylaxis. Among 272 patients on the waiting list for KT, the tuberculin skin test and QFT were positive in 22.8% and 35.3%, respectively. The degree of agreement between the 2 tests was poor (κ = 0.352). CONCLUSIONS: The QFT test did not predict subsequent short-term TB development. Furthermore, a long-term and larger-scale study is needed to confirm our results.

Impact of vitamin D, bisphosphonate, and combination therapy on bone mineral density in kidney transplant patients.

BACKGROUND: Osteoporosis can develop and become aggravated in kidney transplant patients; however, the best preventive options for post-transplantation osteoporosis remain controversial. METHODS: We retrospectively analyzed cohort of 182 renal transplant recipients of mean age 46.7 ± 12.1 years including 47.3% women. Seventy-three patients received neither vitamin D nor bisphosphonate after transplantation (group 1). The other patients were classified into the following 3 groups: calcium plus vitamin D (group 2; n = 40); bisphosphonate (group 3; n = 18); and both regimens (group 4; n = 51). Bone mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry at baseline and at 1 year after transplantation. RESULTS: At 1 year after transplantation, T-scores of the femoral neck and entire femur were significantly decreased in group 1 (-0.23 ± 0.65 [P = .004] and -0.21 ± 0.74 [P = .018], respectively), whereas the lumbar spine was significantly increased in group 4 (0.27 ± 0.79; P = .020). Post hoc analysis demonstrated that the delta T-score was significantly lower in group 1 than in group 4 (P = .009, 0.035, and 0.031 for lumbar spine, femoral neck, and entire femur, respectively). In a multivariate analysis adjusted by age, sex, body mass index, dialysis duration, diabetes, calcineurin inhibitors, estimated glomerular filtration rate, and persistent hyperparathyroidism, both group 2 and group 4 showed protective effects on BMD reduction (odds ratio [OR], 0.165; 95% confidence interval [CI] 0.032-0.845 [P = .031]; and OR, 0.169; 95% CI, 0.045-0.626 [P = .008]; respectively). However, group 3 did not show a protective effect (OR, 0.777; 95% CI, 0.198-3.054; P = .718), because their incidence of persistent hyperparathyroidism after transplantation was significantly higher (50.0%) than the other groups (P < .001). The incidence of bone fractures did not differ among the groups. CONCLUSIONS: Combination therapy with vitamin D and bisphosphonate was the most effective regimen to improve BMD among kidney recipients.

Outcomes of management for potential deceased donors.

BACKGROUNDS: Potential deceased donor management optimization is important for organ recovery maximization. Before optimization, the current state of donor management and predictors for organ recovery require analysis. METHODS: We retrospectively analyzed organ procurement activity and medical management for 2005 to 2010 potential brain death donors at Seoul National University Hospital. RESULTS: Of 316 contacts for potential brain-dead donors, 129 (39.7%) patients were transferred to the donor management team. Among the causes of transfer failure, issues related to proper donor management affected 33%. Expanded criteria donors were 17.9% of transferred donors. Organ recovery was successful in 111 (90.2%) donors. A total of 360 organs were recovered, corresponding to a mean of 2.92 ± 1.37 organs per donor. The absence of organ demand was an important cause of recovery failure among less transplanted organs. Brain death-related complications were identified as follows: acute kidney injury (AKI), defined by AKI network criteria, occurred in 19 (15.4%); cardiopulmonary resuscitation in 5 (3.1%); bacteremia in 12 (9.7%); thrombocytopenia in 24 (19.5%); and diabetes insipidus in 42 (34.1%). AKI was a significant independent risk factor for organ recovery failure in both the liver and kidney (odds ratio [OR] 0.147, 95% confidence interval [0.045, 0.473], P = .001; OR 0.096, 95% confidence interval [0.023, 0.392], P = .001, for kidney and liver, respectively). CONCLUSIONS: Both the transfer success rate and rate of organs transplanted per donor of potential deceased donors remained low in Korea. AKI during potential donor management was a risk factor for kidney and liver recovery failure.

Clinical manifestations of hypercalcemia and hypophosphatemia after kidney transplantation.

INTRODUCTION: Abnormalities of calcium and phosphorus metabolism in end-stage renal disease patients can persist after transplantation. We investigated their natural courses after transplantation, their risk factors for posttransplantation hypercalcemia and hypophosphatemia, and their impacts on allograft outcomes. METHODS: We retrospectively analyzed a total of 490 adult patients who underwent kidney transplantations between 2000 and 2009. RESULTS: The serum calcium continued to increase, and reaching a plateau at around 3 months after transplantation. Thereafter it decreased, reaching a stable level by 2 years. Forty-four patients (9.0%) displayed hypercalcemia within 1 year; it persisted longer than that in 23 subjects (4.7%). Both longer dialysis duration (odds ratio [OR] 1.423; 95% confidence interval [CI], 1.192-1.699) and high intact serum parathyroid hormone (iPTH) level before transplantation (OR 1.002; 95% CI, 1.000-1.003) increased the risk for posttransplantation hypercalcemia. After a significant decrease during the first week, the serum phosphorus level increased, becoming stable between 1 and 6 months after transplantation. Hypophsphatemia occurred in 379 patients (77.3%) with 336 patients displaying hypophosphatemia without hypercalcemia. However, neither hypercalcemia nor hypophosphatemia influenced graft outcomes. Eight patients underwent pretransplantation parathyroidectomy, whereas 4 patients underwent posttransplantation parathyroidectomy. Neither group of patients experienced posttransplantation hypercalcemia. CONCLUSIONS: Both hypercalcemia and hypophosphatemia are common after renal transplantation, especially among patients with a long history of dialysis before transplantation. Strict control of hyperparathyroidism including parathyroidectomy before transplantation may be the appropriate approach to these abnormalities.

Kidney transplantation using expanded criteria donors in Korea.

BACKGROUND: Use of expanded criteria donor (ECD) grafts seeks to solve the organ shortage. We investigated the current status of donor selection and transplantation outcomes. METHODS: We retrospectively analyzed 791 kidney transplantations performed between 1997 and 2009. An expanded criteria deceased donor (ECDD) was defined as an individual who fulfilled the United Network for Organ Sharing criteria or, the Nyberg criteria. An expanded criteria living donor (ECLD) was determined by fulfillment of 1 or more of 5 criteria. RESULTS: Deceased and living donor kidney transplantations were performed in 228 (28.8%) and 563 (71.2%) cases, respectively. Forty-three cases (18.9%) belonged to the ECDDs. The ECDD group showed a lower posttransplantation 1-year estimated glomerular filtration rate (eGFR) than that of the standard criteria deceased donor (SCDD) group (70.7 ± 19.2 vs 48.6 ± 11.5; P < .001). The ECDDs were allocated to older recipients or recipients with more HLA mismatches than SCDDs. The number of ECLD cases was 173 (30.7%). The proportions of each medical abnormality of living donors were as follows: age older than 60 years (0.5%), hypertension (2.5%), obesity (2.1%), low eGFR (25.9%), proteinuria (0%), and microscopic hematuria (1.4%). The ECLD group showed a lower posttransplantation 1-year eGFR than that of the standard criteria living donor (SCLD) group (66.9 ± 16.0 vs 58.3 ± 11.2; P < .001). Graft survival was not different among the donor types (P = .518). CONCLUSIONS: eCDs were 27.3% of the total kidney donors. Posttransplantation 1-year eGFR was lower in the ECD group. However, there was no difference in the graft survival among the different donor types.

Management of patients on the waiting list for deceased donor kidney transplantation.

BACKGROUND: Although the number of wait-listed patients for deceased donor kidney transplantation has been continuously increasing in Korea, no standard guidelines exist for their management. METHODS: We retrospectively analyzed the medical records of our 1,231 wait-listed patients between 2000 and 2010. RESULTS: The time to transplantation of the 201 recipients was 51.9 ± 31.2 months. Ninety-seven patients died while waiting. Diabetic or older patients have increased among new registrants; however, <50% of them have undergone regular screening for malignancy or cardiovascular diseases. Patients with regular screening were more likely to get a chance to receive a transplant (P = .016). Malignancy was newly diagnosed in 26 patients (2.1%) and reversible cardiac ischemia was detected in 9.7%. The presence of anti-HLA antibodies was strongly associated with a lower transplantation rate, whereas blood type O was not. Although use of expanded criteria donor (ECD) kidneys increased, many patients avoided them. CONCLUSION: It is necessary to improve management programs for wait-listed patients by establishing comorbidity screening and ECD education.

Determination of beraprost in human plasma by a high-performance liquid chromatography-tandem mass spectrometry.

A simple, rapid, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for quantification of beraprost, a stable, orally active prostacyclin analogue with vasodilatory, antiplatelet and cytoprotective effects. The analyte and internal standard, indomethacin, were extracted by solid-phase extraction using OASIS HLB cartridge. The chromatographic separation was performed on a C18 column with a mobile of 0.1% formic acid-methanol (30:70, v/v). The highest daughter ion of deprotonated analyte was quantitated in negative ionization by multiple reactions monitoring with a mass spectrometer. The mass transitions m/z 397>269 and m/z 356>312 were used to measure beraprost and internal standard, respectively. The assay exhibited a linear range from 0.02 to 2 ng/mL for beraprost in human plasma. The lower limit of quantitation was 20 pg/mL with a relative standard deviation of less than 20%. The method was validated with respect to linearity, sensitivity, specificity, recovery, accuracy and precision. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic study.

AtBAG6, a novel calmodulin-binding protein, induces programmed cell death in yeast and plants.

Calmodulin (CaM) influences many cellular processes by interacting with various proteins. Here, we isolated AtBAG6, an Arabidopsis CaM-binding protein that contains a central BCL-2-associated athanogene (BAG) domain. In yeast and plants, overexpression of AtBAG6 induced cell death phenotypes consistent with programmed cell death (PCD). Recombinant AtBAG6 had higher affinity for CaM in the absence of free Ca2 + than in its presence. An IQ motif (IQXXXRGXXXR, where X denotes any amino-acid) was required for Ca2 +-independent CaM complex formation and single amino-acid changes within this motif abrogated both AtBAG6-activated CaM-binding and cell death in yeast and plants. A 134-amino-acid stretch, encompassing both the IQ motif and BAG domain, was sufficient to induce cell death. Agents generating oxygen radicals, which are known to be involved in plant PCD, specifically induced the AtBAG6 transcript. Collectively, these results suggest that AtBAG6 is a stress-upregulated CaM-binding protein involved in plant PCD.

Cold accumulation of SCOF-1 transcripts is associated with transcriptional activation and mRNA stability.

Cold acclimation enhances the transcription of several cold regulated (COR) genes. However, little is known about whether the elevation of the transcriptional level of the COR genes is due to transcriptional activation, or mRNA stability by a low temperature. Recently, we cloned a novel cold-inducible zinc finger protein gene from soybean, SCOF-1, which may function as a positive regulator of the COR gene expression . Here we report that the elevation of the SCOF-1 transcript level by cold stress is associated with both transcriptional activation and post-transcriptional mRNA stability under a low temperature. A nuclear run-on assay reveals that cold acclimation elevates the SCOF-1 transcript about three-fold compared to that of non-acclimated soybean nuclei. Furthermore, SCOF-1 transcripts increased substantially by a low temperature in transgenic tobacco plants that constitutively expressed SCOF-1 under the control of a constitutive cauliflower mosaic virus (CaMV) 35S promoter. When a transcription inhibitor, cordycepin, was treated with the deacclimating soybean cell, the decay level of the SCOF-1 transcripts was delayed significantly. This suggests that it may affect de novo protein synthesis, which degrades the SCOF-1 mRNA at room temperature. In addition, a secondary structure may be involved in the mRNA stability of SCOF-1 under a low temperature.

Salviae radix extract prevents cisplatin-induced acute renal failure in rabbits.

The present study was carried out to determine if salviae radix extract (SRE) exerts a beneficial effect against cisplatin-induced renal failure in rabbits. Rabbits were pretreated with SRE orally for 7 days, followed by cisplatin injection (5 mg/kg i.p.). Cisplatin injection caused a reduction in GFR, which was accompanied by an increase in serum creatinine levels. The fractional Na+ excretion was increased by cisplatin injection. PAH uptake by renal cortical slices was inhibited by the administration of cisplatin. Such changes were prevented by SRE pretreatment. Cisplatin injection increased lipid peroxidation, which was prevented by SRE pretreatment. The protective effect of SRE was supported by morphological studies. Cisplatin injection reduced renal blood flow that was not affected by SRE pretreatment. Cisplatin treatment in vitro in renal cortical slices increased LDH release and lipid peroxidation, which were prevented by 0.05% SRE. These results indicate that lipid peroxidation plays a critical role in cisplatin-induced acute renal failure. SRE exerts a protective effect against renal cell injury induced by cisplatin, and its effect may be attributed to its antioxidant action. However, the underlying mechanism by which SRE has antioxidant action remains to be defined.

A unique pattern of mycelial elongation of Blakeslea trispora and its effect on morphological characteristics and beta-carotene synthesis.

The mycelial morphology of Blakeslea trispora was of crucial importance in the production of beta-carotene in submerged cultures of B. trispora. After the spores were inoculated, the time-course variation of mycelial morphology was closely examined under the microscope. With the addition of the non-ionic surfactant (Span 20: Sorbitan monolaurate, E493) to the culture medium, a unique pattern of mycelial elongation was observed: 1) slow formation of germ tubes from spores and 2) appearance of mycelia with very short length, which allowed a well-dispersed growth of B. trispora without significant pellet aggregation. Span 20 appears to act like a paramorphogen. Without Span 20, however, the fungal culture finally formed a big clump of mycelium owing to heavy cross-linking of long mycelia. But the short mycelium maintained in the course of cultivation seemed to be irrelevant to growth inhibition, because the final concentration of dry mycelium was much higher with Span 20 after 3-day cultivation. The 20-fold increase in specific yield of beta-carotene (mg beta-carotene produced per g mycelium) was achieved with this drastic change in the pattern of mycelial elongation. The reason for this result might be more effective mass transfer and/or enhanced sensitivity to environmental oxidative stress in the well-dispersed mycelial cultures of B. trispora.

Bombycis corpus extract prevents amyloid-beta-induced cytotoxicity and protects superoxide dismutase activity in cultured rat astrocytes.

Bombycis corpus(BC) or Bombyx Batryticatus, a batryticated silkworm and white-stiff silkworm, is a drug consisting of the dried larva of silkworm, Mobyz mori L., dead and stiffened due to the infection of Beauveria (Bals.) Vuill. In the present study, we have examined the protective effect of the water extracts against Amyloid- beta(A beta) 25-35 peptide-induced cytotoxicity by microscopic observation and LDH assay, and its action on antioxidative enzymes using cultured astrocyte cells. A beta 25-35-induced cell death was protected by the application of water extract of BC in a dose-dependent manner, and concentrations of 10(-6)to 10(-7)g ml(-1)showed a significant effect compared to exposure of A beta 25-35 alone. When antioxidative enzyme activities such as catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione-S transferase (GST) were assayed after A beta 25-35 treatment, most enzyme activities were decreased in a similar fashion. BC treatment of A beta 25-35-treated astrocytes did not affect the enzyme activities of catalase, GSH-Px and GST. However, only SOD activity was enhanced by BC treatment and this may result from the potentiation of the antioxidative ability of BC. The protective effect of BC against cytotoxicity induced by Abeta 25-35 strongly indicates that BC could be a protective agent for free radical generating compounds, and that Abeta 25-35 is not only a potent lipid peroxide inducer, but can also cause changes in antioxidative enzymes. From the results, it was concluded that BC has a protective effect against Abeta -induced cytotoxicity in cultured astrocyte cells through the inhibition of lipid peroxidation and protection of antioxidative enzymes.