2,3,5,4'-Tetrahydroxystilbene-2-O-ß-glucoside potentiates self-renewal of human dental pulp stem cells via the AMPK/ERK/SIRT1 axis.

AIM: To evaluate the effect of 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside (THSG) on cell proliferation and examine the mechanisms of THSG-enhanced proliferative potential in human dental pulp stem cells (hDPSC). METHODOLOGY: After treatment with THSG, hDPSC were collected. Cell viability was determined by MTS assay, while messenger RNA (mRNA) expressions of proliferation and stem cell markers were analyzed using real-time PCR. Flow cytometry was also conducted to analysis protein expression of stem cell markers. A colony-forming unit assay of hDPSC was carried out. Cellular telomerase activity was also identified using real-time PCR. In addition, proliferation-related proteins involved in the effects of THSG on hDPSC were analyzed by Western blotting. Data were analyzed using one-way analysis of variance and two-tailed Student's t-test. RESULTS: Cell viability, colony-forming rates and telomerase activities of hDPSCs were enhanced after THSG treatment. mRNA expressions of proliferation markers (including expressions of NAD+-dependent histone deacetylase sirtuin 1 (SIRT1), proliferating cell nuclear antigen (PCNA), cyclin D1 and ribonucleotide reductase subunit M2 (RRM2)) increased significantly after THSG treatment (P < 0.05). Treatment with THSG for 3 h significantly augmented SIRT1 protein expression (P < 0.05). Furthermore, activities of proliferation-related proteins (including AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase (ERK) had also significantly increased at 3 h (P < 0.05). After THSG treatment, increased gene and protein expressions of pluripotent-like stem cell markers (including NANOG, OCT4, and SOX2) were observed. CONCLUSIONS: 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-glucoside treatment enhanced the renewal ability and proliferative potential of hDPSCs via the AMPK/ERK/SIRT1 axis, which may provide a novel autogenic cell-based therapeutic strategy in regenerative dentistry.

The rectal mucosa and condomless receptive anal intercourse in HIV-negative MSM: implications for HIV transmission and prevention.

Most HIV transmissions among men who have sex with men (MSM), the group that accounted for 67% of new US infections in 2014, occur via exposure to the rectal mucosa. However, it is unclear how the act of condomless receptive anal intercourse (CRAI) may alter the mucosal immune environment in HIV-negative MSM. Here, we performed a comprehensive characterization of the rectal mucosal immune environment for the phenotype and production of pro-inflammatory cytokines by CD4 and CD8 T cells, global transcriptomic analyses, and the composition of microbiota in HIV-negative MSM. Our results show that compared with men who had never engaged in anal intercourse, the rectal mucosa of MSM engaging in CRAI has a distinct phenotype characterized by higher levels of Th17 cells, greater CD8+ T cell proliferation and production of pro-inflammatory cytokines, molecular signatures associated with mucosal injury and repair likely mediated by innate immune cells, and a microbiota enriched for the Prevotellaceae family. These data provide a high-resolution model of the immunological, molecular, and microbiological perturbations induced by CRAI, will have direct utility in understanding rectal HIV transmission among MSM, and will enhance the design of future biomedical prevention interventions, including candidate HIV vaccines.

Reactivation of Tert in the medial prefrontal cortex and hippocampus rescues aggression and depression of Tert(-/-) mice.

The role of telomerase reverse transcriptase (TERT) has been extensively investigated in the contexts of aging and cancer. Interestingly, Tert(-/-) mice exhibit additional but unexpected aggressive and depressive behaviors, implying the potential involvement of TERT function in mood control. Our conditional rescue experiments revealed that the depressive and aggressive behaviors of Tert(-/-) mice originate from Tert deficiency in two distinct brain structures. Reactivation of Tert in the hippocampus was sufficient to normalize the depressive but not the aggressive behaviors of Tert(-/-) mice. Conversely, re-expression of Tert in the medial prefrontal cortex (mPFC) reversed the aggressive but not the depressive behavior of Tert(-/-) mice. Mechanistically, decreased serotonergic signaling and increased nitric oxide (NO) transmission in the hippocampus transduced Tert deficiency into depression as evidenced by our observation that the infusion of a pharmacological agonist for serotonin receptor 1a (5-HTR1A) and a selective antagonist for neuronal NO synthase into the hippocampus successfully normalized the depressive behavior of Tert(-/-) mice. In addition, increased serotonergic transmission by the 5-HTR1A agonist in the mPFC was sufficient to rescue the aggressive behavior of Tert(-/-) mice. Thus, our studies revealed a novel function of TERT in the pathology of depression and aggression in a brain structure-specific manner, providing direct evidence for the contribution of TERT to emotional control.

CHIP-mediated degradation of transglutaminase 2 negatively regulates tumor growth and angiogenesis in renal cancer.

The multifunctional enzyme transglutaminase 2 (TG2) primarily catalyzes cross-linking reactions of proteins via (γ-glutamyl) lysine bonds. Several recent findings indicate that altered regulation of intracellular TG2 levels affects renal cancer. Elevated TG2 expression is observed in renal cancer. However, the molecular mechanism underlying TG2 degradation is not completely understood. Carboxyl-terminus of Hsp70-interacting protein (CHIP) functions as an ubiquitin E3 ligase. Previous studies reveal that CHIP deficiency mice displayed a reduced life span with accelerated aging in kidney tissues. Here we show that CHIP promotes polyubiquitination of TG2 and its subsequent proteasomal degradation. In addition, TG2 upregulation contributes to enhanced kidney tumorigenesis. Furthermore, CHIP-mediated TG2 downregulation is critical for the suppression of kidney tumor growth and angiogenesis. Notably, our findings are further supported by decreased CHIP expression in human renal cancer tissues and renal cancer cells. The present work reveals that CHIP-mediated TG2 ubiquitination and proteasomal degradation represent a novel regulatory mechanism that controls intracellular TG2 levels. Alterations in this pathway result in TG2 hyperexpression and consequently contribute to renal cancer.

Activation of nuclear PTEN by inhibition of Notch signaling induces G2/M cell cycle arrest in gastric cancer.

Mutation in PTEN has not yet been detected, but its function as a tumor suppressor is inactivated in many cancers. In this study we determined that, activated Notch signaling disables PTEN by phosphorylation and thereby contributes to gastric tumorigenesis. Notch inhibition by small interfering RNA or γ-secretase inhibitor (GSI) induced mitotic arrest and apoptosis in gastric cancer cells. Notch inhibition induced dephosphorylation in the C-terminal domain of PTEN, which led to PTEN nuclear localization. Overexpression of activated Notch1-induced phosphorylation of PTEN and reversed GSI-induced mitotic arrest. Dephosphorylated nuclear PTEN caused prometaphase arrest by interaction with the cyclin B1-CDK1 complex, resulting in their accumulation in the nucleus and subsequent apoptosis. We found a correlation between high expression levels of Notch1 and low survival rates and, similarly, between reduced nuclear PTEN expression and increasing the TNM classification of malignant tumours stages in malignant tissues from gastric cancer patients. The growth of Notch1-depleted gastric tumors was significantly retarded in xenografted mice, and in addition, PTEN deletion restored growth similar to control tumors. We also demonstrated that combination treatment with GSI and chemotherapeutic agents significantly reduced the orthotopically transplanted gastric tumors in mice without noticeable toxicity. Overall, our findings suggest that inhibition of Notch signaling can be employed as a PTEN activator, making it a potential target for gastric cancer therapy.

Auxiliary partial orthotopic liver transplantation as a treatment for hemophilia a: a case report.

A 37-year-old man with moderately severe hemophilia A (factor VIII of 1.2%), who had a normal liver without liver cirrhosis or hepatocellular carcinoma, was referred to our liver transplantation (LT) team. LT was planned for sufficient coagulation factor level maintenance and prophylaxis against future hemorrhagic complications. The donor was the patient's 35-year-old wife, who was nonhemophilic. We performed an auxiliary partial orthotopic liver transplantation (APOLT) with the approval of the Institutional Ethics Committee. A left partial liver graft taken from the donor was orthotopically transplanted to the recipient after resection of the native left hemiliver while preserving the native right lobe. After surgery, the patient tolerated the procedure, and tacrolimus was used to maintained immunosuppression. In this recipient, factor VIII activity significantly increased soon after the APOLT, and has been maintained at >20% without any further bleeding episodes for the past 74 months since the procedure. This finding suggests that APOLT may be an effective alternative treatment for patients with hemophilia A.

Fibroblast growth factor 21 analogue LY2405319 lowers blood glucose in streptozotocin-induced insulin-deficient diabetic mice by restoring brown adipose tissue function.

AIM: To investigate the effects of LY2405319, an analogue of fibroblast growth factor 21 (FGF21), on glucose homeostasis in streptozotocin (STZ)-induced insulin-deficient mice (STZ mice). METHODS: Nine-week-old male C57BL/6J mice were administered a single intraperitoneal injection of STZ (150 mg/kg). One week later, after confirmation of hyperglycaemia, saline or LY2405319 (5 mg/kg) was injected subcutaneously daily for 4 weeks. Changes in glucose homeostasis, energy metabolism and brown adipose tissue (BAT) function were assessed. RESULTS: The STZ mice had elevated blood glucose and reduced plasma FGF21 levels, impaired glucose uptake in the BAT, and BAT mitochondria with absent or swollen cristae and fewer lipid vacuoles. LY2405319 significantly reduced blood glucose levels and this was associated with increased BAT glucose uptake and changes in gene expression and morphology, indicating improved mitochondrial lipid metabolism in the BAT. Importantly, the ability of LY2405319 to lower blood glucose in STZ mice was compromised after removing interscapular BAT. CONCLUSIONS: Our results show that LY2405319 reduces blood glucose levels in insulin-deficient diabetes by improving BAT metabolism. Additional studies investigating the therapeutic potential of FGF21 for the treatment of type 1 diabetes are warranted.

Uncertain areas in the diagnosis of allergic bronchopulmonary aspergillosis in patients with asthma

BACKGROUND AND OBJECTIVE: The prevalence of allergic bronchopulmonary aspergillosis (ABPA) in patients with bronchial asthma remains unknown. We evaluated the roles of various laboratory tests in the diagnosis of ABPA, including, skin prick test (SPT) for Aspergillus fumigatus (Af), and serum Af specific IgE and IgG antibody measurement. METHODS: A total of 50 asthma patients with more than 1000 cell/μL of peripheral blood eosinophils were prospectively collected between January 2007 and September 2011. Evaluations using SPT for Af, serum total IgE and specific IgE antibody to Af by CAP system, IgG antibody to Af by enzyme immunoassay (EIA) or CAP system were performed according to the essential minimal criteria for the diagnosis of ABPA - asthma, immediate cutaneous reactivity to Af, elevated total IgE, and raised Af specific IgE and IgG. RESULTS: Among 50 patients, three patients (6.0%) were diagnosed as ABPA, of whom each confirmed five items of the essential minimal diagnostic criteria for the diagnosis of ABPA. Six patients (12.0%) showed negative responses to Af in SPT, but positive responses in specific IgE by CAP system. Eight patients (16.0%) showed negative responses to IgG to Af by CAP system, but positive responses by enzyme immunoassay (EIA). CONCLUSIONS: SPT and serum IgE to Af measurement by CAP system should be performed simultaneously. It is reasonable to set up cut-off values in Af specific IgE/IgG by CAP system for the differentiation of ABPA from Af sensitised asthma patients

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Ablation of galectin-3 induces p27(KIP1)-dependent premature senescence without oncogenic stress.

Premature senescence induced by oncogenic stimuli or tumor suppressor activation plays opposing roles in tumorigenesis. Here, we propose that galectin-3, a ß-galactoside-binding lectin, regulates premature senescence without oncogenic stress. We detected premature senescence, decreased Skp2, and increased p27(KIP1) expression in galectin-3 knockout MEFs and galectin-3-depleted gastric cancer cells. Interestingly, galectin-3 depletion did not affect other senescence inducers such as p14(ARF), p16(INK4A), and p21(WAF1/CIP1), suggesting that galectin-3-regulated senescence is p27(KIP1) dependent. We demonstrate that galectin-3 depletion decreases retinoblastoma protein (Rb) phosphorylation (Ser780, Ser807/811), cyclin D1 and CDK4 expression, and E2F1 transcriptional activation. Galectin-3 directly interacts with the cyclin D1/CDK4 complex and promotes hyperphosphorylation of Rb. It also blocks the inhibition of E2F1 transcription, thereby increasing the expression of Skp2 and reducing the stability of p27(KIP1) to promote the proliferation of gastric cancer cells. Xenograft mice with galectin-3-depleted gastric cancer cells display tumor growth retardation that is reversed by Skp2 overexpression. Increased expression of galectin-3 is also associated with the advanced TNM (tumor, lymph node, metastasis) system, clinicopathological stage, and lymph node metastases. The probability of survival was significantly decreased in gastric cancer patients with galectin-3(high) p27(KIP1-low)cells. Taken together, our results show that galectin-3 may accelerate gastric tumorigenesis by inhibiting premature senescence.

Chunggan extract (CGX), methionine-and choline-deficient (MCD) diet-induced hepatosteatosis and oxidative stress in C57BL/6 mice.

In the present study, we aimed to evaluate the hepatoprotective and antioxidant effects of Chunggan extract (CGX) in an animal model of hepatosteatosis. The C57BL/6N mice were fed either methionine- and choline-sufficient (MCS) diet (n = 10) or a methionine- and choline-deficient (MCD) diet (n = 50) for 4 weeks, and then they were treated orally with CGX (100 or 200 mg/kg), ursodeoxycholic acid (80 mg/kg, as a positive control), or distilled water (DW, MCS diet group, and MCD diet group) for the final 2 weeks (once per day). The MCD diet induced severe hepatic injury with the typical features of hepatosteatosis in both serum and hepatic tissues. CGX treatment significantly attenuated these alterations in the serum levels including triglyceride (TG), aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total bilirubin. Moreover, CGX also efficiently prevented from the hepatic TG accumulation in the hepatic tissue, evidenced by histopathological findings, compared with the MCD diet. In addition, CGX treatment significantly ameliorated the excessive oxidative stress and antioxidant markers in the serum as well as the hepatic levels of reactive oxygen species, the levels of malondialdehyde, the protein carbonyl, and total antioxidant capacity, and the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. In conclusion, our results indicate the experimental relevance of CGX for potential clinical application in patients with hepatosteatotic disorders and a possible mechanism related to its antioxidant properties.

Cryopreservation induces macrophage colony stimulating factor from human periodontal ligament cells in vitro.

Cryopreservation is used to protect vital periodontal ligaments during the transplantation of teeth. We investigated which gene products implicated in root resorption are upregulated in human periodontal ligament cells by cryopreservation, and whether cryopreservation affects the expression of macrophage-colony stimulating factor (M-CSF) in human periodontal ligament cells. We used customized microarrays to compare gene expression in human periodontal ligament cells cultured from teeth immediately after extraction and from cryopreserved teeth. Based on the result of these assays, we examined M-CSF expression in periodontal ligament cells from the immediately extracted tooth and cryopreserved teeth by real-time PCR, enzyme-linked immunosorbent assay (ELISA), Western blot analysis, and immunofluorescence. We also investigated whether human bone marrow cells differentiate into tartrate-resistant acid phosphatase (TRAP) positive osteoclasts when stimulated with RANKL (Receptor Activator for Nuclear Factor κ B Ligand) together with any secreted M-CSF present in the supernatants of the periodontal ligament cells cultured from the various groups of teeth. M-CSF was twofold higher in the periodontal ligament cells from the rapid freezing teeth than in those from the immediately extracted group (p < 0.05). Cryopreservation increased M-CSF expression in the periodontal ligament cells when analyzed by real time PCR, ELISA, Western blotting, and immunofluorescence (p < 0.05). TRAP positive osteoclasts were formed in response to RANKL and the secreted M-CSF present in the supernatants of all the experimental groups except negative control. These results demonstrate that cryopreservation promotes the production of M-CSF, which plays an important role in root resorption by periodontal ligament cells.

Stabilization of p21 (Cip1/WAF1) following Tip60-dependent acetylation is required for p21-mediated DNA damage response.

The molecular mechanisms controlling post-translational modifications of p21 have been pursued assiduously in recent years. Here, utilizing mass-spectrometry analysis and site-specific acetyl-p21 antibody, two lysine residues of p21, located at amino-acid sites 161 and 163, were identified as Tip60-mediated acetylation targets for the first time. Detection of adriamycin-induced p21 acetylation, which disappeared after Tip60 depletion with concomitant destabilization of p21 and disruption of G1 arrest, suggested that Tip60-mediated p21 acetylation is necessary for DNA damage-induced cell-cycle regulation. The ability of 2KQ, a mimetic of acetylated p21, to induce cell-cycle arrest and senescence was significantly enhanced in p21 null MEFs compared with those of cells expressing wild-type p21. Together, these observations demonstrate that Tip60-mediated p21 acetylation is a novel and essential regulatory process required for p21-dependent DNA damage-induced cell-cycle arrest.

Nitric oxide inhibits androgen receptor-mediated collagen production in human gingival fibroblasts.

UNLABELLED: Lin S-J, Lu H-K, Lee H-W, Chen Y-C, Li C-L, Wang L-F. Nitric oxide inhibits androgen receptor-mediated collagen production in human gingival fibroblasts. J Periodont Res 2012; 47: 701-710. © 2012 John Wiley & Sons A/S Background and Objective: In our previous study, we found that flutamide [an androgen receptor (AR) antagonist] inhibited the up-regulation of collagen induced by interleukin (IL)-1ß and/or nifedipine in gingival fibroblasts. The present study attempted to verify the role of nitric oxide (NO) in the IL-1ß/nifedipine-AR pathway in gingival overgrowth. MATERIAL AND METHODS: Confluent gingival fibroblasts derived from healthy individuals (n = 4) and those with dihydropyridine-induced gingival overgrowth (DIGO) (n = 6) were stimulated for 48 h with IL-1ß (10 ng/mL), nifedipine (0.34 µm) or IL-1ß + nifedipine. Gene and protein expression were analyzed with real-time RT-PCR and western blot analyses, respectively. Meanwhile, Sircol dye-binding and the Griess reagent were, respectively, used to detect the concentrations of total soluble collagen and nitrite in the medium. RESULTS: IL-1ß and nifedipine simultaneously up-regulated the expression of the AR and type-I collagen α1 [Colα1(I)] genes and the total collagen concentration in DIGO cells (p < 0.05). IL-1ß strongly increased the expression of inducible nitric oxide synthase (iNOS) mRNA and the nitrite concentration in both healthy and DIGO cells (p < 0.05). However, co-administration of IL-1ß and nifedipine largely abrogated the expression of iNOS mRNA and the nitrite concentration with the same treatment. Spearman's correlation coefficients revealed a positive correlation between the AR and total collagen (p < 0.001), but they both showed a negative correlation with iNOS expression and the NO concentration (p < 0.001). The iNOS inhibitor, 1400W, enhanced IL-1ß-induced AR expression; furthermore, the NO donor, NONOate, diminished the expression of the AR to a similar extent in gingival fibroblasts derived from both healthy patients and DIGO patients (p < 0.05). CONCLUSION: IL-1ß-induced NO attenuated AR-mediated collagen production in human gingival fibroblasts. The iNOS/NO system down-regulated the axis of AR/Colα1(I) mRNA expression and the production of AR/total collagen proteins by DIGO cells.

Poly(ADP-ribosyl)ation of p53 induces gene-specific transcriptional repression of MTA1.

The metastasis-associated protein 1 (MTA1) is overexpressed in various human cancers and is closely connected with aggressive phenotypes; however, little is known about the transcriptional regulation of the MTA1 gene. This study identified the MTA1 gene as a target of p53-mediated transrepression. The MTA1 promoter contains two putative p53 response elements (p53REs), which were repressed by the p53-inducing drug 5-fluorouracil (5-FU). Notably, 5-FU treatment decreased MTA1 expression only in p53 wild-type cells. p53 and histone deacetylases 1/2 were recruited, and acetylation of H3K9 was decreased on the promoter region including the p53REs after 5-FU treatment. Proteomics analysis of the p53 repressor complex, which was pulled down by the MTA1 promoter, revealed that the poly(ADP-ribose) polymerase 1 (PARP-1) was part of the complex. Interestingly, p53 was poly(ADP-ribose)ylated by PARP-1, and the p53-mediated transrepression of the MTA1 gene required poly(ADP-ribose)ylation of p53. In summary, we report a novel function for poly(ADP-ribose)ylation of p53 in the gene-specific regulation of the transcriptional mode of p53 on the promoter of MTA1.

Epidermal regeneration by ent-16α, 17-dihydroxy-kauran-19-oic acid isolated from Siegesbeckia pubescens.

OBJECTIVES: Keratinocyte stem/progenitor cells (KSCs) are known to regenerate epidermal tissue which they perform through to their great regenerative capacity. MATERIALS AND METHODS: Because stimulation of resident KSCs may regenerate epidermal tissue, we devised a strategy to find an appropriate KSC activator from natural products and to develop it as a skin-rejuvenating agent. RESULTS: Ent-16α, 17-dihydroxy-kauran-19-oic acid (DHK) isolated from Siegesbeckia pubescens exhibited a KSC-stimulating effect during screening of natural products. DHK increased proliferation and migration of KSCs using the Akt/ERK pathway. We further examined the mechanism of KSC stimulation and found that phosphorylation of Y1068 epithelial growth factor receptor (EGFR) was significantly increased. Functional inhibition of EGFR using neutralizing antibody and a chemical inhibitor, AG1478, attenuated DHK-induced KSC stimulation. In a 3D culture model of KSCs, DHK treatment significantly induced establishment of fully stratified epidermis and increased numbers of p63-positive cells. Likewise, DHK treatment significantly accelerated healing of epidermal wounds created by laser and dermatome, and increased p63-positive cells, in animal models. CONCLUSION: Collectively, these results indicate that DHK regenerates epidermal tissue mainly through EGFR phosphorylation. As DHK has diverse advantages over recombinant growth factors for commercialization (that is long-term stability and skin permeability), DHK might be applied to wound-healing agents and to a basic materials used in cosmetics.

Hdm2 negatively regulates telomerase activity by functioning as an E3 ligase of hTERT.

In this study, we identified posttranslational regulation of human telomerase reverse-transcriptase (hTERT) by the E3 ligase Hdm2. The telomerase activity generated by exogenous hTERT in U2OS cells was reduced on adriamycin treatment. The overexpressed levels of hTERT were also decreased under the same conditions. These processes were reversed by treatment with a proteasome inhibitor or depletion of Hdm2. Furthermore, intrinsic telomerase activity was increased in HCT116 cells with ablation of Hdm2. Immunoprecipitation analyses showed that hTERT and Hdm2 bound to each other in multiple domains. Ubiquitination analyses showed that Hdm2 could polyubiquitinate hTERT principally at the N-terminus, which was further degraded in a proteasome-dependent manner. An hTERT mutant with all five lysine residues at the N-terminus of hTERT that mutated to arginine became resistant to Hdm2-mediated ubiquitination and degradation. In U2OS cells, depletion of Hdm2 or addition of the Hdm2-resistant hTERT mutant strengthened the cellular protective effects against apoptosis. Similar results were obtained with the Hdm2-stable H1299 cell line. These observations indicate that Hdm2 is an E3 ligase of hTERT.

Runx3 is required for the differentiation of lung epithelial cells and suppression of lung cancer.

Human lung adenocarcinoma, the most prevalent form of lung cancer, is characterized by many molecular abnormalities. K-ras mutations are associated with the initiation of lung adenocarcinomas, but K-ras-independent mechanisms may also initiate lung tumors. Here, we find that the runt-related transcription factor Runx3 is essential for normal murine lung development and is a tumor suppressor that prevents lung adenocarcinoma. Runx3-/- mice, which die soon after birth, exhibit alveolar hyperplasia. Importantly, Runx3-/- bronchioli exhibit impaired differentiation, as evidenced by the accumulation of epithelial cells containing specific markers for both alveolar (that is SP-B) and bronchiolar (that is CC10) lineages. Runx3-/- epithelial cells also express Bmi1, which supports self-renewal of stem cells. Lung adenomas spontaneously develop in aging Runx3+/- mice ( approximately 18 months after birth) and invariably exhibit reduced levels of Runx3. As K-ras mutations are very rare in these adenomas, Runx3+/- mice provide an animal model for lung tumorigenesis that recapitulates the preneoplastic stage of human lung adenocarcinoma development, which is independent of K-Ras mutation. We conclude that Runx3 is essential for lung epithelial cell differentiation, and that downregulation of Runx3 is causally linked to the preneoplastic stage of lung adenocarcinoma.

Giant dermatofibroma with granular cell changes: side-effect of bee-venom acupuncture?

Dermatofibroma (DF) is a common benign fibrohistiocytic tumour with a predilection for the legs in middle-aged women. Giant DF, a rare clinical variant of DF, is characterized by its unusually large size. Granular cell change is typical of granular cell tumour, but can be observed in diverse cell lineages. Traumatic factors may be involved in the pathogenesis of giant DF and cellular granularity. We describe a 49-year-old Korean man with a giant DF showing granular cell differentiation, which may have been caused in part by multiple treatments with bee-venom acupuncture.

A standardized extract of Ginkgo biloba suppresses doxorubicin-induced oxidative stress and p53-mediated mitochondrial apoptosis in rat testes.

BACKGROUND AND PURPOSE: Doxorubicin evokes oxidative stress and precipitates cell apoptosis in testicular tissues. The aim of this study was to investigate whether the Ginkgo biloba extract 761 (EGb), a widely used herbal medicine with potent anti-oxidant and anti-apoptotic properties, could protect testes from such doxorubicin injury. EXPERIMENTAL APPROACH: Sprague-Dawley male rats (8 weeks old) were given vehicle, doxorubicin alone (3 mg kg(-1) every 2 days for three doses), EGb alone (5 mg kg(-1) every 2 days for three doses), or EGb followed by doxorubicin (each dose administered 1 day after EGb). At 7 days after the first drug treatment oxidative and apoptotic testicular toxicity was evaluated by biochemical, histological and flow cytometric analyses. KEY RESULTS: Compared with controls, testes from doxorubicin-treated rats displayed impaired spermatogenesis, depleted haploid germ cell subpopulations, increased lipid peroxidation products (malondialdehyde), depressed antioxidant enzyme activities (superoxide dismutase, glutathione peroxidase and glutathione), reduced antioxidant enzyme expression (superoxide dismutase) and elevated apoptotic indexes (pro-apoptotic modulation of Bcl-2 family proteins, intensification of p53 and Apaf-1, release of mitochondrial cytochrome c, activation of caspase-3 and increase of terminal deoxynucleotidyl transferase nick-end labelling/sub-haploid cells), while EGb pretreatment effectively alleviated all of these doxorubicin-induced abnormalities in testes. CONCLUSIONS AND IMPLICATIONS: These results demonstrate that EGb protected against the oxidative and apoptotic actions of doxorubicin on testes. EGb may be a promising adjuvant therapy medicine, potentially ameliorating testicular toxicity of this anti-neoplastic agent in clinical practice.

TERT promotes cellular and organismal survival independently of telomerase activity.

The expression level of the telomerase catalytic subunit (telomerase reverse transcriptase, TERT) positively correlates with cell survival after exposure to several lethal stresses. However, whether the protective role of TERT is independent of telomerase activity has not yet been clearly explored. Here, we genetically evaluated the protective roles of both TERT and telomerase activity against cell death induced by staurosporine (STS) and N-methyl-D-aspartic acid (NMDA). First generation (G1) TERT-deficient mouse embryonic fibroblasts (MEFs) displayed an increased sensitivity to STS, while TERT transgenic MEFs were more resistant to STS-induced apoptosis than wild-type. Deletion of the telomerase RNA component (TERC) failed to alter the sensitivity of TERT transgenic MEFs to STS treatment. Similarly, NMDA-induced excitotoxic cell death of primary neurons was suppressed by TERT, but not by TERC both in vitro and in vivo. Specifically, NMDA accelerated death of TERT-deficient mice, while TERT transgenic mice showed enhanced survival when compared with wild-type littermates after administration of NMDA. In addition, the transgenic expression of TERT protected motor neurons from apoptosis induced by sciatic nerve axotomy. These results indicate that telomerase activity is not essential for the protective function of TERT. This telomerase activity-independent TERT function may contribute to cancer development and aging independently of telomere lengthening.