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Background: The considerable prevalence and worse outcomes of asthma-COPD overlap (ACO) in COPD have been reported, and optimal introduction of ICS is essential for ACO. However, diagnostic criteria for ACO consist of multiple laboratory tests, which is challenging during this COVID-19 era. The purpose of this study was to create a simple questionnaire to diagnose ACO in patients with COPD. Methods: Among 100 COPD patients, 53 were diagnosed with ACO based on the Japanese Respiratory Society Guidelines for ACO. Firstly, 10 candidate questionnaire items were generated and further selected by a logistic regression model. An integer-based scoring system was generated based on the scaled estimates of items. Results: Five items, namely a history of asthma, wheezing, dyspnea at rest, nocturnal awakening, and weather- or season-dependent symptoms, contributed significantly to the diagnosis of ACO in COPD. History of asthma was related to FeNO >35 ppb. Two points were assigned to history of asthma and 1 point to other items in the ACO screening questionnaire (ACO-Q), and the area under the receiver operating characteristic curve was 0.883 (95% CI: 0.806–0.933). The best cutoff point was 1 point, and the positive predictive value was 100% at a cutoff of 3 points or higher. The result was reproducible in the validation cohort of 53 patients with COPD. Conclusions: A simple questionnaire, ACO-Q, was developed. Patients with scores ≥3 could be reasonably recommended to be treated as ACO, and additional laboratory testing would be recommended for patients with 1 and 2 points.

Background: Extramammary Paget's disease (EMPD) is a rare intraepithelial adenocarcinoma that mainly affects the anogenital and axillary regions. Although its etiology has not been fully elucidated, there is evidence that androgen receptors (AR) are expressed in most cases of EMPD. However, the role of androgen signaling in the pathogenesis of EMPD remains unclear., Objective: To evaluate the role of androgen signaling in tumor growth of AR-positive EMPD., Methods: Patient-derived organoids were established and cultured from two AR-positive EMPD patients: one man and one woman. Cultured organoids were treated with androgen agonists and/or antagonists, then subjected to analysis of changes in organoid proliferation, as well as changes in androgen signaling pathway-specific genes., Results: Organoid cultures were established from each EMPD sample. These organoids were immunohistologically and genetically identical to the original tumor. For each organoid sample, viable cell number increased in response to androgen exposure. The mRNA level of Fkbp5, a known AR target gene, increased in a concentration-dependent manner in organoids exposed to the synthetic androgen R1881. Conversely, the AR inhibitor darolutamide suppressed the viable cell number in a concentration-dependent manner. The mRNA expression levels of MKI67 and Fkbp5 were also suppressed by darolutamide., Conclusion: Our results indicate that androgen signaling is a key pathway involved in the growth of AR-positive EMPD. Therefore, androgen signaling inhibition may be a novel treatment option for EMPD patients who require systemic therapy., Competing Interests: Conflict of interest HM, TT and MU belong to JSR corporation., (Copyright © 2023. Published by Elsevier B.V.)

Mammalian auditory hair cells are not spontaneously replaced. Their number and coordinated polarization are fairly well-maintained and both these factors might be essential for the cochlear amplifier. Cell cycle regulation has critical roles in regulating appropriate cell size and cell number. However, little is known about the physiological roles of the Hippo pathway, which is one of the most important signaling cascades that regulates cell growth, differentiation, and regenerative capacity in the cochlear sensory epithelium. Herein, we investigated the in vivo role of the large tumor suppressor 1 (LATS1), an essential kinase in the Hippo/yes-associated protein pathway, in the cochlea using the LATS1 knockout mice. LATS1 was expressed in hair cells and supporting cells. It was strongly expressed on the surface of the cuticular plate of the organ of Corti. We found that LATS1 knockout caused congenital hearing loss due to the irregular orientation and slightly reduced number of hair cells, whereas the number of supporting cells remained unchanged. On the surface of the hair cells, the kinocilium and stereocilia were dispersed during and after morphogenesis. However, the expression of the receptor-independent polarity regulators, such as Par3 or Gαi, was not affected. We concluded that LATS1 has an indispensable role in the maturation of mammalian auditory hair cells, but not in the development of the supporting cells, and thus, has a role in the hearing acquisition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: Chemical intervention of autophagy has been investigated in clinical trials for various age-related conditions such as sarcopenia and neurodegeneration. However, at present, no autophagy inducer has been established as a disease-modifying agent against neurodegenerative diseases., Methods: We screened a library consisting of 796 medicines clinically approved (in Japan) for autophagy enhancers as potential neurodegeneration therapeutics using HeLa cells stably expressing green fluorescent protein-microtubule-associated protein light chain 3 (GFP-LC3) followed by an analysis of the molecular mechanisms using various neuronal models., Results: The primary screening identified 152 hits in a static cellular state. A widely available Alzheimer's disease drug, memantine, which antagonizes N-Methyl-d-aspartate receptor (NMDAR), was one of the hits. Memantine increased the levels of LC3-II in a dose-dependent and time-dependent manner, and upregulated autophagic flux. In addition, the pharmacological effects of memantine on autophagy were independent of mTORC1 activity and NMDAR activation. Furthermore, a VPS34 inhibitor suppressed the memantine-induced LC3-II upregulation, suggesting that memantine may affect VPS34 complex activity. Notably, intracellular Huntington's disease-specific aggregates of elongated huntingtin, a well-established autophagy substrate, were significantly decreased by memantine. In addition, memantine enhanced elimination of degraded mitochondrial in neurons derived from induced pluripotent stem cells of PARK2 or PARK6 patients, who exhibited defective PINK1/parkin-mediated mitophagy, suggests that memantine accelerated the clearance of damaged mitochondria., Conclusion: These findings indicate that memantine may be beneficial for the treatment of neurodegeneration characterized by the abnormal accumulation of autophagy or mitophagy substrates., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The low turnover rate of thyroid follicular cells and the lack of a long-term thyroid cell culture system have hampered studies of thyroid carcinogenesis. We have now established a thyroid organoid culture system that supports thyroid cell proliferation in vitro. The established mouse thyroid organoids performed thyroid functions including thyroglobulin synthesis, iodide uptake, and the production and release of thyroid hormone. Furthermore, transplantation of the organoids into recipient mice resulted in the formation of normal thyroid-like tissue capable of iodide uptake and thyroglobulin production in vivo. Finally, forced expression of oncogenic NRAS (NRAS Q61R ) in thyroid organoids established from p53 knockout mice and transplantation of the manipulated organoids into mouse recipients generated a model of poorly differentiated thyroid cancer. Our findings suggest that this newly developed thyroid organoid culture system is a potential research tool for the study of thyroid physiology and pathology including thyroid cancer., (Copyright © 2018 Elsevier Inc. All rights reserved.)

FZR1 (fizzy-related protein homolog; also known as CDH1 [cell division cycle 20 related 1]) functions in the cell cycle as a specific activator of anaphase-promoting complex or cyclosome ubiquitin ligase, regulating late mitosis, G 1 phase, and activation of the G 2 -M checkpoint. FZR1 has been implicated as both a tumor suppressor and oncoprotein, and its precise contribution to carcinogenesis remains unclear. Here, we examined the role of FZR1 in tumorigenesis and cancer therapy by analyzing tumor models and patient specimens. In an Fzr1 gene-trap mouse model of B-cell acute lymphoblastic leukemia (B-ALL), mice with Fzr1 -deficient B-ALL survived longer than those with Fzr1 -intact disease, and sensitivity of Fzr1 -deficient B-ALL cells to DNA damage appeared increased. Consistently, conditional knockdown of FZR1 sensitized human B-ALL cell lines to DNA damage-induced cell death. Moreover, multivariate analyses of reverse-phase protein array of B-ALL specimens from newly diagnosed B-ALL patients determined that a low FZR1 protein expression level was an independent predictor of a longer remission duration. The clinical benefit of a low FZR1 expression level at diagnosis was no longer apparent in patients with relapsed B-ALL. Consistent with this result, secondary and tertiary mouse recipients of Fzr1 -deficient B-ALL cells developed more progressive and radiation-resistant disease than those receiving Fzr1 -intact B-ALL cells, indicating that prolonged inactivation of Fzr1 promotes the development of resistant clones. Our results suggest that reduction of FZR1 increases therapeutic sensitivity of B-ALL and that transient rather than tonic inhibition of FZR1 may be a therapeutic strategy., (© 2017 by The American Society of Hematology.)

Purpose: The variant isoforms of CD44 (CD44v), which has been associated with treatment resistance and tumor recurrence, are contributed to the feature of some of the new cell surface markers for cancer stem cells. The aim of this study is to address the prognostic significant of CD44v expression in upper tract urothelial cancer (UTUC)., Materials and Methods: We retrospectively analyzed the medical records of 110 patients treated surgically for≥pT2 UTUC. To determine the biological significance of CD44v in UTUC, we examined the immunohistochemical expression of CD44v9 and its association with clinical features and oncological outcomes., Results: During the mean follow-up of 4.8 years, tumor recurrence, including local and distant metastasis, was observed in 57 patients (51.8%), and 42 patients (38.2%) died of the disease. The incidence of ureter cancers was significantly higher in patients expressing CD44v9. In this series, 37 patients in the CD44v9-positive group (45.1%) and 5 (17.9%) in the CD44v9-negative group died of the disease. Kaplan-Meier curves revealed that cancer-specific survival and recurrence-free survival rates were significantly lower in the CD44v9-positive group than in the CD44v9-negative group (P = 0.032 and P = 0.038, respectively). A multivariate analysis identified the expression of CD44v9 as one of the independent risk factors for cancer-specific survival (P = 0.040, hazard ratio = 2.67) in addition to tumor grade G3, and also for recurrence-free survival (P = 0.028, hazard ratio = 2.33), in addition to tumor grade G3 and lymphovascular invasion., Conclusions: The expression of CD44v9 may be a new biomarker of malignant potential in muscle invasive UTUC and provide additional prognostic information in patients with UTUC., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

CD44 expressed in cancer cells was shown to stabilize cystine transporter (xCT) that uptakes cystine and excretes glutamate to supply cysteine as a substrate for reduced glutathione (GSH) for survival. While targeting CD44 serves as a potentially therapeutic stratagem to attack cancer growth and chemoresistance, the impact of CD44 targeting in cancer cells on metabolic systems of tumors and host tissues in vivo remains to be fully determined. This study aimed to reveal effects of CD44 silencing on alterations in energy metabolism and sulfur-containing metabolites in vitro and in vivo using capillary electrophoresis-mass spectrometry and quantitative imaging mass spectrometry (Q-IMS), respectively. In an experimental model of xenograft transplantation of human colon cancer HCT116 cells in superimmunodeficient NOG mice, snap-frozen liver tissues containing metastatic tumors were examined by Q-IMS. As reported previously, short hairpin CD44 RNA interference (shCD44) in cancer cells caused significant regression of tumor growth in the host liver. Under these circumstances, the CD44 knockdown suppressed polyamines, GSH and energy charges not only in metastatic tumors but also in the host liver. In culture, HCT116 cells treated with shCD44 decreased total amounts of methionine-pool metabolites including spermidine and spermine, and reactive cysteine persulfides, suggesting roles of these metabolites for cancer growth. Collectively, these results suggest that CD44 expressed in cancer accounts for a key regulator of metabolic interplay between tumor and the host tissue., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Cancer stem-like cells express high amount of CD44 variant8-10 which protects cancer cells from redox stress. We have demonstrated by immunohistochemical analysis and Western blotting, and reverse-transcription polymerase chain reaction, that CD44 variant8-10 and c-Myc tend to show the inversed expression manner in gastric cancer cells. That is attributable to the oxidative stress-induced canonical Wnt activation, and furthermore, the up-regulation of the downstream molecules, one of which is oncogenic c-Myc, is not easily to occur in CD44 variant-positive cancer cells. We have also found out that CD44v8-10 expression is associated with the turn-over of the c-Myc with the experiments using gastric cancer cell lines. This cannot be simply explained by the model of oxidative stress-induced Wnt activation. CD44v8-10-positive cancer cells are enriched at the invasive front. Tumor tissue at the invasive area is considered to be composed of heterogeneous cellular population; dormant cancer stem-like cells with CD44v8-10 (high)/ Fbw7 (high)/ c-Myc (low) and proliferative cancer stem-like cells with CD44v8-10 (high)/ Fbw7 (low)/ c-Myc (high)., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Introduction: Epithelial cell adhesion molecule (EpCAM) is expressed in tumors with an epithelial cell of origin, in a heterogeneous manner. Prostate cancer stem-like cells highly express EpCAM. However, little is known about how EpCAM is involved in the ability of cells to adapt to micro-environmental changes in available growth factors, which is one of the essential biological phenotypes of cancer stem-like cells (CSCs)., Methods: EpCAM-high and EpCAM-low subpopulations of cells were established from the prostate cancer cell line PC-3. Signal transductions in response to serum starvation, and on the exposure to EGF ligand or the specific inhibitor were analyzed in terms. Furthermore, we analyzed the expression level of amino acid transporters which contribute to the activation of mTOR signal between the two subgroups., Results: EpCAM-high and EpCAM-low PC-3 subpopulations showed markedly different responses to serum starvation. EpCAM expression was positively correlated with activation of the mTOR and epithelial growth factor receptor (EGFR) signaling pathways. Furthermore, AMP-activated protein kinase (AMPK) was gradually de-activated in EpCAM-low PC-3 cells in the absence of serum., Conclusions: EpCAM regulates the AMPK signaling pathway, essential for the response to growth factors characterized by EGF. LAT1, the amino acid transporter stabilized at the cellular membrane by EpCAM, is likely to be responsible for the difference in the susceptibility to EGF between EpCAM-high and EpCAM-low PC-3 cells., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Prostaglandin E2 (PGE2) is a proinflammatory mediator and activates the canonical Wnt-β-catenin signaling pathway in hematopoietic stem cells. The SZ95 cell line was established from human sebaceous gland cells and is studied as a model system for these cells. Given that 2D culture of SZ95 cells does not recapitulate the organization of sebaceous glands in situ, we developed a 3D culture system for these cells and examined the effects of PGE2 on cell morphology and function., Results: SZ95 cells maintained in 3D culture formed organoids that mimicked the organization of sebaceous glands in situ, including the establishment of a basement membrane. Organoids exposed to PGE2 were larger and adopted a more complex organization compared with control organoids. PGE2 activated the canonical Wnt signaling pathway as well as increased cell viability and proliferation, mitochondrial metabolism, and lipid synthesis in the organoids., Conclusions: Culture of SZ95 cells in 3D culture system recapitulates the structure and susceptibility to PGE2 of sebaceous glands in situ and should prove useful for studies of the response of these glands to inflammation and other environmental stressors. Our results also implicate PGE2-induced activation of canonical Wnt signaling pathway in regulation of the morphology,proliferation, and function of "semi-vivo" sebaceous glands., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Normal cells undergo a growth-arrested status that is produced by p53-dependent down-regulation of histone H2AX. Immortality is developed after abrogation of the H2AX-diminished state, which is associated with genomic instability (often with tetraploidy) and the induction of mutations in either the Arf or p53 gene. However, the role of Arf in control of H2AX expression and genome stability is still unclear. Here, we show that both Arf and p53 are required for the down-regulation of H2AX and formation of the growth-arrested state. Wild-type (WT) mouse embryonic fibroblasts (MEFs) subjected to tetraploidization with DNA lesions did not undergo mitotic catastrophe-associated cell death and stayed in a growth-arrested state, until immortality was attained with mutations in the Arf/p53 module and recovery of H2AX expression. Whereas tetraploidization was essential for immortalization of WT MEFs, this event was not required for immortalization of MEFs containing mutations in Arf/p53 and these cells still underwent mitotic catastrophe-associated cell death. Thus, WT MEFs are protected from immortalization with genome stability, which is abrogated with tetraploidization and mutation of either Arf or p53., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Gestational choriocarcinoma is a malignant trophoblastic tumor that usually occurs in the uterus after pregnancy. The tumor is curable with advanced chemotherapy, but the molecular mechanism of choriocarcinoma tumorigenesis remains unclear. This is partly because the low incidence makes it difficult to obtain clinical samples for investigation and because an appropriate choriocarcinoma cell model to study the tumorigenesis has not been developed. We have established a new choriocarcinoma cell line, induced choriocarcinoma cell-1 (iC(3)-1), that possesses unique characteristics compared to other choriocarcinoma cell lines, including production of tumors that consist of the two types of cells commonly found in choriocarcinoma and mimicking of the clinical pathology. Existing trophoblast cell lines utilized in previous choriocarcinoma studies have had significantly dissimilar gene expression profiles. Therefore, it is important to choose an appropriate cell line for a particular study based on the characteristics of the cell line. In this study, to clarify the genetic characteristics of iC(3)-1 and to explore the tumorigenesis mechanism, we examined the gene profile of iC(3)-1 compared to those of existing cell lines and normal placental tissue. Bioinformatics analysis showed that several characteristic genes, IGF1R, CHFR, MUC3A, TAF7, PARK7, CDC123 and PSMD8, were significantly upregulated in iC(3)-1 compared to BeWo and JEG3 cells. Interestingly, HAS2, CD44 and S100P were significantly upregulated in iC(3)-1 compared to parental HTR8/SVneo cells and normal third trimester placenta. Choriocarcinoma samples also showed immunoreactivity to HAS2, CD44 and S100. In summary, the gene expression profile of iC(3)-1 suggests that studies using this cell line can make an important contribution to improved understanding of choriocarcinoma tumorigenesis., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Differentiation of placental trophoblast stem (TS) cells to trophoblast giant (TG) cells is accompanied by transition from a mitotic cell cycle to an endocycle. Here, we report that Cdh1, a regulator of the anaphase-promoting complex/cyclosome (APC/C), negatively regulates mitotic entry upon the mitotic/endocycle transition. TS cells derived from homozygous Cdh1 gene-trapped (Cdh1(GT/GT)) murine embryos accumulated mitotic cyclins and precociously entered mitosis after induction of TS cell differentiation, indicating that Cdh1 is required for the switch from mitosis to the endocycle. Furthermore, the Cdh1(GT/GT) TS cells and placenta showed aberrant expression of placental differentiation markers. These data highlight an important role of Cdh1 in the G2/M transition during placental differentiation., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Invasiveness, cellular atypia, and proliferation are hallmarks of malignant gliomas. To effectively target each of these characteristics, it is important to understand their sequence during tumorigenesis. However, because most gliomas are diagnosed at an advanced stage, the chronology of gliomagenesis milestones is not well understood. The aim of the present study was to determine the onset of these characteristics during tumor development. Brain tumor-initiating cells (BTICs) were established by overexpressing H-Ras(V12) in normal neural stem/progenitor cells isolated from the subventricular zone of adult mice harboring a homozygous deletion of the Ink4a/Arf locus. High-grade malignant brain tumors were then created by orthotopic implantation of 10(5) BTICs into the forebrain of 6-week-old wild-type mice. Micewere killed every week for 5 weeks, and tumors were assessed for cellular atypia, proliferation, hemorrhage, necrosis, and invasion. All mice developed highly invasive, hypervascular glioblastoma-like tumors. A 100% penetrance rate and a 4-week median survival were achieved. Tumor cell migration along fiber tracts started within days after implantation and was followed by perivascular infiltration of tumor cells with marked recruitment of reactive host cells. Next, cellular atypia became prominent. Finally, mass proliferation and necrosis were observed in the last stage of the disease. Video monitoring of BTICs in live brain slices confirmed the early onset of migration, as well as the main cell migration patterns. Our results showed that perivascular and intraparenchymal tumor cell migration precede tumor mass formation in the adult brain, suggesting the need for an early and sustained anti-invasion therapy.

Gestational choriocarcinoma is a malignant trophoblastic tumor. The development of novel molecular-targeted therapies is needed to reduce the toxicity of current multiagent chemotherapy and to treat successfully the chemoresistant cases. The molecular mechanisms underlying choriocarcinoma tumorigenesis remain uncharacterized, however, and appropriate choriocarcinoma animal models have not yet been developed. In this study, we established a choriocarcinoma model by inoculating mice with induced-choriocarcinoma cell-1 (iC³-1) cells, generated from HTR8/SVneo human trophoblastic cells retrovirally transduced with activated H-RAS (HRASV12). The iC³-1 cells exhibited constitutive activation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways and developed into lethal tumors in all inoculated mice. Histopathological analysis revealed that the tumors consisted of two distinct types of cells, reminiscent of syncytiotrophoblasts and cytotrophoblasts, as seen in the human choriocarcinoma. The tumors expressed HLA-G and cytokeratin (trophoblast markers) and hCG (a choriocarcinoma marker). Comparative analysis of gene expression profiles between iC³-1 cells and parental HTR8/SVneo cells revealed that iC³-1 cells expressed matrix metalloproteinases, epithelial-mesenchymal transition-related genes, and SOX3 at higher levels than parental trophoblastic cells. Administration of SOX3-specific short-hairpin RNA decreased SOX3 expression and attenuated the tumorigenic activity of iC³-1 cells, suggesting that SOX3 overexpression might be critically involved in the pathogenesis of choriocarcinoma. Our murine model represents a potent new tool for studying the pathogenesis and treatment of choriocarcinoma., (Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

L-type amino-acid transporter 1 (LAT1) is the first identified light chain of CD98 molecule, disulfide-linked to a heavy chain of CD98. Following cDNA cloning of chicken full-length LAT1, we have constructed targeting vectors for the disruption of chicken LAT1 gene from genomic DNA of chicken LAT1 consisting of 5.4kb. We established five homozygous LAT1-disrupted (LAT1(-/-)) cell clones, derived from a heterozygous LAT1(+/-) clone of DT40 chicken B cell line. Reactivity of anti-chicken CD98hc monoclonal antibody (mAb) with LAT1(-/-) DT40 cells was markedly decreased compared with that of wild-type DT40 cells. All LAT1(-/-) cells were deficient in L-type amino-acid transporting activity, although alternative-splice variant but not full-length mRNA of LAT1 was detected in these cells. LAT1(-/-) DT40 clones showed outstandingly slow growth in liquid culture and decreased colony-formation capacity in soft agar compared with wild-type DT40 cells. Cell-cycle analyses indicated that LAT1(-/-) DT40 clones have prolonged cell-cycle phases compared with wild-type or LAT1(+/-) DT40 cells. Knockdown of human LAT1 by small interfering RNAs resulted in marked in vitro cell-growth inhibition of human cancer cells, and in vivo tumor growth of HeLa cells in athymic mice was significantly inhibited by anti-human LAT1 mAb. All these results indicate essential roles of LAT1 in the cell proliferation and occurrence of malignant phenotypes and that LAT1 is a promising candidate as a molecular target of human cancer therapy., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Serum stimulation leads to activation of the serum response factor (SRF)-mediated transcription of immediate-early genes such as c-fos via various signal transduction pathways. We have previously reported that promyelocytic leukemia protein (PML) is involved in the transcriptional regulation by SRF. PML is one of the well-known substrates for modification by small ubiquitin-related modifier-1 (SUMO-1) and several SUMO-1-modified proteins associate with PML. Here, we report that SRF is modified by SUMO-1 chiefly at lysine(147) within the DNA-binding domain. Substitution of this target lysine for alanine did not affect the translocation of SRF to PML-nuclear bodies. The SRF mutant augmented the transcriptional activity under Rho A-stimulated condition but not under serum-starved condition, suggesting that activated SRF is suppressed by its sumoylation. These data support the transcriptional role of SUMO-1 conjugating system in cellular serum response.

In this study, we tested the polymerase chain reaction (PCR)-method to diagnose cutaneous leishmaniasis (CL) by taking exudate materials from lesions with cotton swabs, using our previously tested (PCR) panel comprised of Leishmania (Viannia) panamensis, L. (V.) braziliensis, L. (V.) guyanensis, L. (Leishmania) mexicana and L. (L.) amazonensis. The objectives of the present study were to improve the sampling method convenient for the patients and to test the usefulness of samples taken with cotton swabs. Sixteen patients were clinically diagnosed to have CL including one case of diffuse cutaneous leishmaniasis (DCL) in Ecuador and the causative Leishmania parasites were identified by PCR. All the 12 samples from CL patients of La Mana, positive for Leishmania DNA, were identified as L. (V.) panamensis, while two from CL of Huigra and one from DCL of San Ignacio were L. (L.) mexicana. In the field condition, taking biopsy material is not only painful but sometimes causes iatrogenic bacterial infections. Considering the sensitivity of the test, and convenient sampling procedure, it may be suggested that collection of exudates using cotton swabs may be a better alternative to biopsy sample for PCR-diagnosis of CL.

Cell surface adhesion molecules are crucial for the development and/or pathogenesis of various diseases including cancer. CD44 has received much interest as a major adhesion molecule that is involved in tumor progression. We have previously demonstrated that the ectodomain of CD44 undergoes proteolytic cleavage by membrane-associated metalloproteases in various tumor cell lines. The remaining membrane-bound CD44 cleavage product can be detected using antibodies against the cytoplasmic domain of CD44 (anti-CD44cyto antibody). However, the cleavage of CD44 in primary human tumors has not been investigated. Using Western blots with anti-CD44cyto antibody to assay human tumor tissues, we show that the CD44 cleavage product can be detected in 58% (42 of 72) of gliomas but not in normal brain. Enhanced CD44 cleavage was also found in 67% (28 of 42) of breast carcinomas, 45% (5 of 11) of non-small cell lung carcinomas, 90% (9 of 10) of colon carcinomas, and 25% (3 of 12) of ovarian carcinomas. Tumors expressing a CD44 splice variant showed a significantly higher incidence of enhanced CD44 cleavage. The wide prevalence of CD44 cleavage suggests that it plays an important role in the pathogenesis of human tumors.

We cloned a novel human gene encoding a tissue-specific calpain, termed htra-3, which is highly homologous to the tra-3 sex determination gene of Caenorhabditis elegans. The predicted htra-3 polypeptide had similarity to the calpain large subunits in domain organization throughout domains I to III, but the sequences of domain IV lacked calcium-binding motifs. Northern blot analysis revealed high expression in the colon, small intestine and testis. Radiation hybrid mapping localized the htra-3 gene to chromosome 11q14 (2.53cR apart from WI-3895). Western blot analysis demonstrated that the approximately 73-kDa htra-3 protein was transiently expressed in COS-7 cells. These observations, together with the genetic information in C.elegans, suggest a unique function for htra-3 protein.

CD44 is a cell surface adhesion molecule postulated to control lymphocyte recirculation by facilitating entry into lymphoid tissue. Tumour cells transfected to overexpress the epithelial variant CD44R1 readily gain access to lymph nodes and distant metastatic sites in animal models, possibly by mimicking circulating lymphocytes. To investigate if human tumours display altered CD44 expression we performed reverse transcriptase a polymerase chain reaction (PCR) analysis of CD44 in 49 specimens from normal colonic mucosa, primary colon and rectal tumours, normal liver, and metastases of 20 patients. The haematopoietic variant CD44H was the principal isoform amplified in all of the specimens, However, 12/14 primary tumours and 16/16 metastatic potential. Moreover, the relative increase with only 2 of 13 normal mucosa specimens. This increase in CD44R1 relative to CD44H expressed by human colon carcinoma cells may increase their metastatic potential. Moreover, the relative increase in PCR amplification of CD44R1 compared with that of CD44H may provide a sensitive method for detecting primary and metastatic colon carcinoma cells in small biopsy specimens.

Chronic lymphocytic leukemia (CLL) is a usually indolent disease that can assume an aggressive clinical course in some patients. To develop assays that would be predictive of how a particular patient's disease would evolve, we studied the expression of proliferating cell nuclear antigen (PCNA) by Western blotting in 40 patients with CLL. The concentration of PCNA, a cofactor for delta DNA-dependent DNA polymerase, is indicative of the proliferative state of the cell. Significantly lower PCNA levels were observed in earlier stage CLL when compared with more advanced disease. The leukemic cell proliferative rate, assessed by lymphocyte doubling time and flow cytometry, also correlated significantly with the level of PCNA expression. These results suggest that a high level of PCNA in the cells of CLL patients at presentation identifies a subgroup of patients whose CLL cells have a higher proliferative activity and who may, therefore, have a potentially shorter survival.