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Pulmonary lymphangitic carcinomatosis (PLC) is associated with a poor prognosis in patients with non-small cell lung cancer (NSCLC). We sought to determine prognostic value of pretherapeutic fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in NSCLC with radiologically diagnosed PLC. We retrospectively reviewed 50 NSCLC patients with radiologically diagnosed PLC. Among eight clinical variables and five imaging parameters, metabolic PLC burden, which represents the overall tumor burden of PLC, and cPLC, which represents the location and extent of PLC in a three-grade system, were used. In multivariate analyses for progression-free survival, metabolic PLC burden (P = 0.0181), cPLC (P = 0.0401), and clinical stage (P = 0.0284) were identified as independent prognostic factors. High metabolic PLC burden had a worse prognosis, and the prognosis of cPLC3 was significantly worse than that of cPLC1 or cPLC2. In univariate analyses for overall survival, only age (P = 0.0073) was identified a prognostic factor. In conclusion, FDG PET/CT parameters were identified as independent prognostic factors in NSCLC with radiologically diagnosed PLC. Furthermore, a combination of anatomical and metabolic information about PLC obtained using FDG PET/CT provides insight into the overall tumor burden of PLC and is useful in predicting prognosis., (© 2023. The Author(s).)

Mycobacterium avium complex pulmonary disease (MAC-PD) requires long-term treatment. We analyzed the outcomes of 992 MAC-PD patients according to disease severity and compared the outcomes of intermittent and daily therapy for mild disease. Patients were divided into groups according to severity using the body mass index, age, cavity, erythrocyte sedimentation rate, and sex (BACES) system, and culture conversion rates were evaluated. We also evaluated the effects of intermittent treatment on the culture conversion rates in mild disease group. Using the BACES, 992 patients were divided into mild (n = 331), moderate (n = 503), and severe (n = 158) disease groups, and culture conversion at the end of treatment was achieved in 85% (282/331), 80% (403/503), and 61% (97/158), respectively. Differences in culture conversion among the severity groups were significant (p < 0.001). In patients with mild disease, culture conversion rates were similar between intermittent (84%, 166/198) and daily (87%, 116/133) treatment (p = 0.396), and intermittent antibiotic therapy did not negatively impact culture conversion (adjusted hazard ratio 1.08; confidence interval 0.83-1.41; p = 0.578). MAC-PD patients with mild disease had higher culture conversion rates. Daily and intermittent therapy yielded similar culture conversion rates for mild disease. Treatment strategies with lower pill burden may be applicable in mild MAC-PD., (© 2022. The Author(s).)

Macrophages are increased in human benign prostatic hyperplasia and prostate cancer. We generate a Pb-Csf1 mouse model with prostate-specific overexpression of macrophage colony-stimulating factor (M-Csf/Csf1). Csf1 overexpression promotes immune cell infiltration into the prostate, modulates the macrophage polarity in a lobe-specific manner, and induces senescence and low-grade prostatic intraepithelial neoplasia (PIN). The Pb-Csf1 prostate luminal cells exhibit increased stem cell features and undergo an epithelial-to-mesenchymal transition. Human prostate cancer patients with high CSF-1 expression display similar transcriptional alterations with the Pb-Csf1 model. P53 knockout alleviates senescence but fails to progress PIN lesions. Ablating epithelial Gp130 but not Il1r1 substantially blocks PIN lesion formation. The androgen receptor (AR) is downregulated in Pb-Csf1 mice. ChIP-Seq analysis reveals altered AR binding in 2482 genes although there is no significant widespread change in global AR transcriptional activity. Collectively, our study demonstrates that increased macrophage infiltration causes PIN formation but fails to transform prostate cells., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Chronic obstructive pulmonary disease (COPD), an established risk factor for lung cancer, remains largely undiagnosed and untreated before lung cancer surgery. We evaluated the effect of perioperative bronchodilator therapy on lung function changes in COPD patients who underwent surgery for non-small cell lung cancer (NSCLC). From a database including NSCLC patients undergoing lung resection, COPD patients were identified and divided into two groups based on the use of bronchodilator during the pre- and post-operative period. Changes in forced expiratory volume in 1 s (FEV 1 ) and postoperative complications were compared between patients treated with and without bronchodilators. Among 268 COPD patients, 112 (41.8%) received perioperative bronchodilator, and 75% (84/112) were newly diagnosed with COPD before surgery. Declines in FEV 1 after surgery were alleviated by perioperative bronchodilator even after adjustments for related confounding factors including surgical extent, surgical approach and preoperative FEV 1 (adjusted mean difference in FEV 1 decline [95% CI] between perioperative bronchodilator group and no perioperative bronchodilator group; - 161.1 mL [- 240.2, - 82.0], - 179.2 mL [- 252.1, - 106.3], - 128.8 mL [- 193.2, - 64.4] at 1, 4, and 12 months after surgery, respectively). Prevalence of postoperative complications was similar between two groups. Perioperative bronchodilator therapy was effective to preserve lung function, after surgery for NSCLC in COPD patients. An active diagnosis and treatment of COPD are required for surgical candidates of NSCLC.

Prostate adenocarcinoma undergoes neuroendocrine differentiation to acquire resistance toward antihormonal therapies. The underlying mechanisms have been investigated extensively, among which Sox2 has been shown to play a critical role. However, genetic evidence in mouse models for prostate cancer to support the crucial role of Sox2 is missing. The adult mouse prostate luminal cells contain both castration-resistant Sox2-expressing Sca-1 + cells and castration-responsive Sca-1 - cells. We show that both types of the luminal cell are susceptible to oncogenic transformation induced by loss of function of the tumor suppressor Pten. The tumors derived from the Sca-1 + cells are castration resistant and are more inclined to develop castration-induced neuroendocrine differentiation. Genetic ablation of Sox2 suppresses neuroendocrine differentiation but does not impact the castration-resistant property. This study provides direct genetic evidence that Sox2 is necessary for androgen ablation-induced neuroendocrine differentiation of Pten null prostate adenocarcinoma, corroborates that the lineage status of the prostate cancer cells is a determinant for its propensity to exhibit lineage plasticity, and supports that the intrinsic features of cell-of-origin for prostate cancers can dictate their clinical behaviors.

Neuroendocrine prostate cancer (NEPC) is an aggressive variant of prostate cancer that either develops de novo or arises from prostate adenocarcinoma as a result of treatment resistance. Although the prostate basal cells have been shown to directly generate tumor cells with neuroendocrine features when transduced with oncogenic signaling, the identity of the cell-of-origin for de novo NEPC remains unclear. We show that the TACSTD2 high human prostate luminal epithelia cells highly express SOX2 and are relatively enriched in the transition zone prostate. Both TACSTD2 high and TACSTD2 low luminal cells transduced by constitutively activated AKT1 (caAKT1), and c-Myc can form organoids containing versatile clinically relevant tumor cell lineages with regard to the expression of AR and the neuroendocrine cell markers Synaptophysin and Chromogranin A. Tumor organoid cells derived from the TACSTD2 high luminal cells are more predisposed to neuroendocrine differentiation along passaging and are relatively more castration-resistant. Knocking down TACSTD2 and SOX2 both attenuate neuroendocrine differentiation of tumor organoid cells. This study demonstrates de novo neuroendocrine differentiation of the human prostate luminal epithelial cells induced by caAKT1 and c-Myc and reveals an impact of cellular status on initiation of lineage plasticity.

Pulmonary disease (PD) due to nontuberculous mycobacteria (NTM) is increasing globally, but specific biomarkers for NTM-PD have not been established. As circulating miRNAs are promising biomarkers for various diseases, we investigated whether miRNAs have potential as NTM-PD biomarkers. Sera from 12 NTM-PD patients due to Mycobacterium avium, M. intracellulare, M. abscessus, or M. massiliense and three healthy controls were initially evaluated via small RNA sequencing. Multiple miRNAs showed significant differences in expression in patients compared to in healthy controls, with some expression differences unique to PD caused by a specific mycobacterial species. Notably, 14 miRNAs exhibited significant expression differences in PD associated with all four mycobacteria. Validation by quantitative reverse-transcription-PCR in an additional 40 patients with NTM-PD and 40 healthy controls confirmed that four differentially expressed miRNAs (hsa-miR-484, hsa-miR-584-5p, hsa-miR-625-3p, and hsa-miR-4732-5p) showed significantly higher serum expressions in NTM-PD patients than in controls. Receiver operating characteristic curve analysis of these four miRNAs supported the discriminative potential for NTM-PD and their combination provided an improved diagnostic value for NTM-PD. Furthermore, bioinformatics analysis revealed their 125 target genes, which were mostly associated with immune responses. Collectively, this study identified four miRNAs as potential biomarkers for NTM-PD and provided insight into NTM-PD pathophysiology.

The cancer risk among solid organ transplantation recipients in East-Asia has been insufficiently studied. This study estimated de novo cancer incidence in kidney and liver recipients 2008-2015, compared with the general population in Korea using nationwide data. This is a retrospective cohort study using nationwide health insurance claims data. The study population was comprised of cancer-free 10,085 kidney recipients and 3,822 liver recipients. Standardized incidence ratio (SIR) of cancer using indirect standardization was calculated. Compared with the general population, the cancer risk increased by 3.19-fold in male and 2.56-fold in female kidney recipients. By cancer type, a notably increased SIR was observed for Kaposi sarcoma, renal cancer, skin cancer, and non-Hodgkin's lymphoma in male and for bladder cancer, renal cancer, and non-Hodgkin's lymphoma in female kidney recipients. In liver recipients, the SIR of all cancers was 3.43 in males and 2.30 in females. In male liver recipients, the SIRs for Kaposi sarcoma, non-Hodgkin's lymphoma, myeloid leukemia, and skin cancer and in female recipients those for non-Hodgkin's lymphoma and liver cancer were prominent. A greatly higher SIRs for overall cancer and non-Hodgkin's lymphoma in kidney and liver recipients aged 0-19 were observed, compared with recipients in other age group. The incidence of de novo cancer in kidney and liver recipients was higher than the general population and common types were different. Strategies of cancer prevention and screening after kidney and liver transplantation should be developed in response to the incidence of common types of de novo cancers.

The peroxisome proliferator-activated receptor-γ (PPARγ) improves whole-body insulin sensitivity by regulating the adipogenic and metabolic functions of mature adipocytes. We have previously demonstrated that an active splice variant of X-box binding protein 1 (XBP1s) enhances PPARγ expression during adipogenesis. In this study, we investigated the role of XBP1s, particularly with respect to PPARγ, in the mechanisms underlying insulin sensitivity in mature adipocytes. Insulin was able to stimulate XBP1s generation by activating inositol-requiring enzyme 1 (IRE1) α and was also able to increase its transcriptional activity by inducing nuclear translocation. XBP1s also upregulated the levels of phosphorylated IRS1 and AKT, demonstrating a positive feedback regulatory mechanism linking insulin and XBP1s. XBP1s enhanced the expression of fibroblast growth factor 21 and, in turn, increased PPARγ activity, translocation of GLUT4 to the cell surface, and glucose uptake rate in adipocytes. In addition, XBP1s abolished palmitate-induced insulin resistance in adipocytes by increasing adiponectin secretion, repressing the secretion of pro-inflammatory adipokines such as leptin, monocyte chemoattractant protein 1, and tumor necrosis factor α, and decreasing fatty acid release. These findings provide a novel mechanism by which XBP1s stimulate insulin sensitivity in adipocytes through fibroblast growth factor 21 induction and PPARγ activation.

In-depth molecular pathogenesis of ground-glass nodular lung adenocarcinoma has not been well understood. The objectives of this study were to identify genomic alterations in ground-glass nodular lung adenocarcinomas and to investigate whether viral transcripts were detected in these tumors. Nine patients with pure (n = 4) and part-solid (n = 5) ground-glass nodular adenocarcinomas were included. Six were females with a median age of 58 years. We performed targeted exon sequencing and RNA sequencing. EGFR (n = 10), IDH2 (n = 2), TP53 (n = 1), PTEN (n = 1), EPHB4 (n = 1), and BRAF (n = 1) were identified as driver mutations by targeted exon sequencing. Vasculogenesis-associated genes including NOTCH4 and TGFBR3 expression were significantly downregulated in adenocarcinoma tissue versus normal tissue (adjusted P values < 0.001 for both NOTCH4 and TGFBR3). In addition, five novel fusion gene loci were identified in four lung adenocarcinomas. However, no significant virus-associated transcripts were detected in tumors. In conclusions, EGFR, IDH2, TP53, PTEN, EPHB4, and BRAF were identified as putative driver mutations of ground-glass nodular adenocarcinomas. Five novel fusion genes were also identified in four tumors. Viruses do not appear to be involved in the tumorigenesis of ground-glass nodular lung adenocarcinoma.

Glioblastoma is a highly aggressive and malignant type of cancer that is apoptosis resistant and difficult to cure by conventional cancer therapies. In this regard, an oncolytic adenovirus that selectively targets the tumour tissue and induces tumour cell lysis is a promising treatment option. We designed and constructed a hypoxia-responsive and cancer-specific modified human telomerase reverse transcriptase (H5CmTERT) promoter to drive replication of an oncolytic adenovirus (H5CmTERT-Ad). To enhance the anti-tumour efficacy of H5CmTERT-Ad against malignant glioblastoma, we also generated an H5CmTERT-Ad expressing secretable trimeric tumour necrosis factor-related apoptosis-inducing ligand (H5CmTERT-Ad/TRAIL). H5CmTERT promoter-regulated oncolytic adenoviruses showed cancer-specific and superior cell-killing effect in contrast to a cognate control oncolytic adenovirus replicating under the control of the endogenous adenovirus promoter. The cancer cell-killing effects of H5CmTERT-Ad and H5CmTERT-Ad/TRAIL were markedly higher during hypoxia than normoxia owing to hypoxia responsiveness of the promoter. H5CmTERT-Ad/TRAIL showed more potent anti-tumour efficacy than H5CmTERT-Ad did in a xenograft model of TRAIL-resistant subcutaneous and orthotopic glioblastoma through superior induction of apoptosis and more extensive virus distribution in the tumour tissue. Altogether, our findings show that H5CmTERT-Ad/TRAIL can promote dispersion of an oncolytic adenovirus through robust induction of apoptosis in a highly TRAIL-resistant glioblastoma.

The E3 ubiquitin ligase adaptor speckle-type POZ protein (SPOP) is frequently dysregulated in prostate adenocarcinoma (PC), via either somatic mutations or mRNA downregulation, suggesting an important tumour suppressor function. To examine its physiologic role in the prostate epithelium in vivo, we generated mice with prostate-specific biallelic ablation of Spop. These mice exhibited increased prostate mass, prostate epithelial cell proliferation, and expression of c-MYC protein compared to littermate controls, and eventually developed prostatic intraepithelial neoplasia (PIN). We found that SPOP WT can physically interact with c-MYC protein and, upon exogenous expression in vitro, can promote c-MYC ubiquitination and degradation. This effect was attenuated in PC cells by introducing PC-associated SPOP mutants or upon knockdown of SPOP via short-hairpin-RNA, suggesting that SPOP inactivation directly increases c-MYC protein levels. Gene Set Enrichment Analysis revealed enrichment of Myc-induced genes in transcriptomic signatures associated with SPOP MT . Likewise, we observed strong inverse correlation between c-MYC activity and SPOP mRNA levels in two independent PC patient cohorts. The core SPOP MT ;MYC High transcriptomic response, defined by the overlap between the SPOP MT and c-MYC transcriptomic programmes, was also associated with inferior clinical outcome in human PCs. Finally, the organoid-forming capacity of Spop-null murine prostate cells was more sensitive to c-MYC inhibition than that of Spop-WT cells, suggesting that c-MYC upregulation functionally contributes to the proliferative phenotype of Spop knock-out prostates. Taken together, our data highlight SPOP as an important regulator of luminal epithelial cell proliferation and c-MYC expression in prostate physiology, identify c-MYC as a novel bona fide SPOP substrate, and help explain the frequent inactivation of SPOP in human PC. We propose SPOP MT -induced stabilization of c-MYC protein as a novel mechanism that can increase total c-MYC levels in PC cells, in addition to amplification of c-MYC locus.

The development of a low cost and highly active alternative to the commercial Pt/C catalysts used in the oxygen reduction reaction (ORR) requires a facile and environmentally-friendly synthesis process to facilitate large-scale production and provide an effective replacement. Transition metals, in conjunction with nitrogen-doped carbon, are among the most promising substitute catalysts because of their high activity, inexpensive composition, and high carbon monoxide tolerance. We prepared a polyaniline-derived Fe-N-C catalyst for oxygen reduction using a facile one-pot process with no additional reagents. This process was carried out by ultrasonicating a mixture containing an iron precursor, an aniline monomer, and carbon black. The half-wave potential of the synthesized Fe-N-C catalyst for the ORR was only 10 mV less than that of a commercial Pt/C catalyst. The optimized Fe-N-C catalyst showed outstanding performance in a practical anion exchange membrane fuel cell (AEMFC), suggesting its potential as an alternative to commercial Pt/C catalysts for the ORR.

Wnt10b, an endogenous inhibitor of adipogenesis, maintains preadipocytes in an undifferentiated state by suppressing adipogenic transcription factors. We have previously demonstrated that Wnt10b transcription during adipogenesis is negatively regulated by X-box-binding protein 1 (XBP1), an important transcription factor of the unfolded protein response. In this report, we demonstrate that XBP1s can directly induce the transcription of microRNA-148a, which in turn mediates the silencing of Wnt10b mRNA during adipogenic differentiation of 3T3-L1 cells. Stability of Wnt10b mRNA was found to be significantly increased by knockdown of XBP1s. Using computational algorithms, a set of microRNAs was predicted to bind Wnt10b mRNA, of which microRNA-148a was selected as a potential target for XBP1s. Our results revealed that microRNA-148a could bind to the 3'UTR of Wnt10b mRNA. Its ectopic expression significantly suppressed both Wnt10b expression and β-catenin activity. When we altered the expression of XBP1 in 3T3-L1 cells, microRNA-148a levels changed accordingly. A potential XBP1 response element was found in the promoter region of microRNA-148a, and XBP1s directly bound to this response element as shown by point mutation analysis and chromatin immunoprecipitation assay. In addition, a microRNA-148a mimic significantly restored adipogenic potential in XBP1-deficient 3T3-L1 cells. These findings provide the first evidence that XBP1s can regulate Wnt10b by a post-transcriptional mechanism through directly inducing microRNA-148a.

The clinical efficacy of conventional chemotherapeutic agent, methotrexate (MTX), can be limited by its very short plasma half-life, the drug resistance, and the high dosage required for cancer cell suppression. In this study, a new drug delivery system is proposed to overcome such limitations. To realize such a system, MTX was intercalated into layered double hydroxides (LDHs), inorganic drug delivery vehicle, through a co-precipitation route to produce a MTX-LDH nanohybrid with an average particle size of approximately 130 nm. Biodistribution studies in mice bearing orthotopic human breast tumors revealed that the tumor-to-liver ratio of MTX in the MTX-LDH-treated-group was 6-fold higher than that of MTX-treated-one after drug treatment for 2 hr. Moreover, MTX-LDH exhibited superior targeting effect resulting in high antitumor efficacy inducing a 74.3% reduction in tumor volume compared to MTX alone, and as a consequence, significant survival benefits. Annexin-V and propidium iodine dual staining and TUNEL analysis showed that MTX-LDH induced a greater degree of apoptosis than free MTX. Taken together, our data demonstrate that a new MTX-LDH nanohybrid exhibits a superior efficacy profile and improved distribution compared to MTX alone and has the potential to enhance therapeutic efficacy via inhibition of tumor proliferation and induction of apoptosis.

With the increasing use of culture-expanded mesenchymal stromal cells (MSCs) for cell therapies, factors that regulate the cellular characteristics of MSCs have been of major interest. Oxygen concentration has been shown to influence the functions of MSCs, as well as other normal and malignant stem cells. However, the underlying mechanisms of hypoxic responses and the precise role of hypoxia-inducible factor-1α (Hif-1α), the master regulatory protein of hypoxia, in MSCs remain unclear, due to the limited span of Hif-1α stabilization and the complex network of hypoxic responses. In this study, to further define the significance of Hif-1α in MSC function during their self-renewal and terminal differentiation, we established adult bone marrow (BM)-derived MSCs that are able to sustain high level expression of ubiquitin-resistant Hif-1α during such long-term biological processes. Using this model, we show that the stabilization of Hif-1α proteins exerts a selective influence on colony-forming mesenchymal progenitors promoting their self-renewal and proliferation, without affecting the proliferation of the MSC mass population. Moreover, Hif-1α stabilization in MSCs led to the induction of pluripotent genes (oct-4 and klf-4) and the inhibition of their terminal differentiation into osteogenic and adipogenic lineages. These results provide insights into the previously unrecognized roles of Hif-1α proteins in maintaining the primitive state of primary MSCs and on the cellular heterogeneities in hypoxic responses among MSC populations.

Adenoviruses (Ad) have been investigated for their efficacy in reducing primary tumors after local intratumoral administration. Despite high Ad concentrations and repetitive administration, the therapeutic efficacy of Ad has been limited because of rapid dissemination of the Ad into the surrounding normal tissues and short maintenance of Ad biological activity in vivo. To maximize the therapeutic potential of Ad-mediated gene therapeutics, we investigated the efficacy of local, sustained Ad delivery, using an injectable alginate gel matrix system. The biological activity of Ad loaded in alginate gel was prolonged compared with naked Ad, as evidenced by the high green fluorescent protein gene transduction efficiency over an extended time period. Moreover, oncolytic Ad encapsulated in alginate gel elicited 1.9- to 2.4-fold greater antitumor activity than naked Ad in both C33A and U343 human tumor xenograft models. Histological and quantitative PCR analysis confirmed that the oncolytic Ad/alginate gel matrix system significantly increased preferential replication and dissemination of oncolytic Ad in a larger area of tumor tissue in vivo. Taken together, these results show that local sustained delivery of oncolytic Ad in alginate gel augments therapeutic effect through selective infection of tumor cells, sustained release and prolonged maintenance of Ad activity.

Brown adipose tissue is specialized to burn lipids for thermogenesis and energy expenditure. Second-generation antipsychotics (SGA) are the most commonly used drugs for schizophrenia with several advantages over first-line drugs, however, it can cause clinically-significant weight gain. To reveal the involvement of brown adipocytes in SGA-induced weight gain, we compared the effect of clozapine, quetiapine, and ziprasidone, SGA with different propensities to induce weight gain, on the differentiation and the expression of brown fat-specific markers, lipogenic genes and adipokines in a mouse brown preadipocyte cell line. On Oil Red-O staining, the differentiation was inhibited almost completely by clozapine (40 μM) and partially by quetiapine (30 μM). Clozapine significantly down-regulated the brown adipogenesis markers PRDM16, C/EBPβ, PPARγ2, UCP-1, PGC-1α, and Cidea in dose- and time-dependent manners, whereas quetiapine suppressed PRDM16, PPARγ 2, and UCP-1 much weakly than clozapine. Clozapine also significantly inhibited the mRNA expressions of lipogenic genes ACC, SCD1, GLUT4, aP2, and CD36 as well as adipokines such as resistin, leptin, and adiponectin. In contrast, quetiapine suppressed only resistin and leptin but not those of lipogenic genes and adiponectin. Ziprasidone (10 μM) did not alter the differentiation as well as the gene expression patterns. Our results suggest for the first time that the inhibition of brown adipogenesis may be a possible mechanism to explain weight gain induced by clozapine and quetiapine.

When we treated rat bone marrow stromal cells (rBMSCs) with neuronal differentiation induction media, typical unfolded protein response (UPR) was observed. BIP/GRP78 protein expression was time-dependently increased, and three branches of UPR were all activated. ATF6 increased the transcription of XBP1 which was successfully spliced by IRE1. PERK was phosphorylated and it was followed by eIF2alpha phosphorylation. Transcription of two downstream targets of eIF2alpha, ATF4 and CHOP/GADD153, were transiently up-regulated with the peak level at 24 h. Immunocytochemical study showed clear coexpression of BIP and ATF4 with NeuN and Map2, respectively. UPR was also observed during the neuronal differentiation of mouse embryonic stem (mES) cells. Finally, chemical endoplasmic reticulum (ER) stress inducers, thapsigargin, tunicamycin, and brefeldin A, dose-dependently increased both mRNA and protein expressions of NF-L, and, its expression was specific to BIP-positive rBMSCs. Our results showing the induction of UPR during neuronal differentiations of rBMSCs and mES cells as well as NF-L expression by ER stress inducers strongly suggest the potential role of UPR in neuronal differentiation.

We have previously isolated a novel protein "B/K" that contains two C2-like domains. Here, we report the isolation and mRNA distribution of a human B/K isoform, and protein kinase A (PKA)-dependent phosphorylation of the B/K protein. The 1.5 kb human B/K cDNA clone exhibits 89% and 97% identities with rat B/K in the sequences of nucleotide and amino acid, respectively. Human B/K isoform encodes a 474 amino acid protein and shows structural features similar to the rat counterpart including two C2 domains, three consensus sequences for PKA, absence of a transmembrane region, and conservation of the N-terminal cysteine cluster. On Northern and dot blot analyses, a 3.0 kb B/K transcript was abundantly present in human brain, kidney, and prostate. Among the brain regions, strong signals were observed in the frontal and temporal lobes, the hippocampus, the hypothalamus, the amygdala, the substantia nigra, and the pituitary. Recombinant B/K proteins containing three consensus sites for PKA was very efficiently phosphorylated in vitro by PKA catalytic subunit. B/K protein which was overexpressed in LLC-PK1 cells was also strongly phosphorylated in vivo by vasopressin analog DDAVP, and PKA-specific inhibitor H 89 as well as type 2 vasopressin receptor antagonist specifically suppressed DDAVP-induced B/K phosphorylation. These results suggest that B/K proteins play a role as potential substrates for PKA in the area where they are expressed.

Liver cirrhosis is one of the major complications of hepatitis C virus (HCV) infection, but the mechanisms underlying HCV-related fibrogenesis are still not clear. Although the roles of HCV core protein remain poorly understood, it is supposed to play an important role in the regulation of cellular growth and hepatocarcinogenesis. The aim of this study was to examine the role of HCV core protein on the hepatic fibrogenesis. We established an in vitro co-culture system with primary hepatic stellate cell (HSC) isolated from rats, and a stable HepG2-HCV core cell line which had been transfected with HCV core gene. The expressions of fibrosis-related molecules transforming growth factor beta1 (TGF-beta1), transforming growth factor beta receptor II (TGFbetaRII), alpha-smooth muscle actin (alpha-SMA) and connective tissue growth factor (CTGF) were analyzed via histological or molecular methods. In addition, the expression levels of matrix metaloprotinase-2 (MMP-2) and collagen type I (Col I) from the co-cultured media were measured by zymogram and ELISA, respectively. The expressions of alpha-SMA, TGF-beta1, Col I, TGFbetaRII and MMP-2 were significantly increased in the co-culture of stable HepG2-HCV core with HSC. Moreover, the significant increases of CTGF and TGF-beta1 in the HCV core-expressing cells were observed by either Northern or Western blot analysis. These results suggest that HCV core protein may contribute to the hepatic fibrogenesis via up-regulation of CTGF and TGF-beta1.

Delta(12)-Prostaglandin (PG) J(2) is known to elicit an anti-neoplastic effects via apoptosis induction. Previous study showed Delta(12)-PGJ(2)-induced apoptosis utilized caspase cascade through cytochrome c-dependent pathways in HeLa cells. In this study, the cellular mechanism of Delta(12)-PGJ(2)- induced apoptosis in HeLa cells, specifically, the role of two mitochondrial factors; bcl-2 and apoptosis-inducing factor (AIF) was investigated. Bcl-2 attenuated Delta(12)-PGJ(2)-induced caspase activation, loss of mitochondrial transmembrane potential (Deltapsi(m)), nuclear fragmentation, DNA laddering, and growth curve inhibition for approximately 24 h, but not for longer time. AIF was not released from mitochondria, even if the Deltapsi(m) was dissipated. One of the earliest events observed in Delta(12)-PGJ(2)-induced apoptotic events was dissipation of Deltapsi(m), the process known to be inhibited by bcl-2. Pre-treatment of z-VAD- fmk, the pan-caspase inhibitor, resulted in the attenuation of ym depolarization in Delta(12)-PGJ(2)-induced apoptosis. Up-regulation of Sox-4 protein by Delta(12)-PGJ(2) was observed in HeLa and bcl-2 overexpressing HeLa B4 cell lines. Bcl-2 overexpression did not attenuate the expression of Sox-4 and its expression coincided with other apoptotic events. These results suggest that Delta(12)-PGJ(2) induced Sox-4 expression may activate another upstream caspases excluding the caspase 9-caspase 3 cascade of mitochondrial pathway. These and previous findings together suggest that Delta(12)-PGJ(2)-induced apoptosis in HeLa cells is caspase-dependent, AIF-independent events which may be affected by Sox-4 protein expression up-regulated by Delta(12)-PGJ(2).

The levels of expressions and catalytic activities of cytochrome P450 (CYP1A1) and glutathione-S-transferase class mu (GSTM1) enzymes in lungs and their metabolic balance may be an important determinant host factor underlying lung cancer. Genetic differences in metabolism, MspI restriction sites, Ile-Val polymorphism of CYP1A1 gene, and the null genotype of GSTM1 have been reported to be associated with susceptibility to lung cancer. The present studies were undertaken to establish frequencies of the polymorphic genotypes of CYP1A1 and GSTM1 in Koreans, and to evaluate linkage disequilibrium of the genotypes associated with higher lung cancer risks among Koreans. GSTM1(-) genotype was found in 52% of control subjects, whereas it was found in 55% of lung cancer patients. The allelic variants in CYP1A1 were distributed differently in lung cancer patients and controls. The heterozygous genotype frequency of the MspI site in lung cancer patients (53%) was higher than in controls (49%). The frequency of Ile/Val genotype of CYP1A1 was low in lung cancer patients, which are mostly squamous cell carcinoma.