Identification of treatment strategies for Mycoplasma genitalium-related urethritis in male patients by culturing and antimicrobial susceptibility testing

Mycoplasma genitalium was first isolated from urethral swab specimens of male patients with non-gonococcal urethritis. However, the isolation of M. genitalium strains from clinical specimens has been difficult. Co-cultivation with Vero cells is one available technique for the isolation of M. genitalium. The strains that can be used for antimicrobial susceptibility testing by broth dilution or agar dilution methods are limited. Macrolides, such as azithromycin (AZM), have the strongest activity against M. genitalium. However, AZM-resistant strains have emerged and spread. Mutations in the 23S rRNA gene contribute to the organism's macrolide resistance, which is similar to the effects of the mutations in macrolide-resistant Mycoplasma pneumoniae. Of the fluoroquinolones, moxifloxacin (MFLX) and sitafloxacin have the strongest activities against M. genitalium, while levofloxacin and ciprofloxacin are not as effective. Some clinical trials on the treatment of M. genitalium-related urethritis are available in the literature. A doxycycline regimen was microbiologically inferior to an AZM regimen. For cases of treatment failure with AZM regimens, MFLX regimens were effective.

Variability of trinucleotide tandem repeats in the MgPa operon and its repetitive chromosomal elements in Mycoplasma genitalium

Mycoplasma genitalium, a human pathogen associated with sexually transmitted diseases, is unique in that it has the smallest genome of any known free-living organism. Despite its small genome, 4.7 % of the total genomic sequence is devoted to making the MgPa adhesin operon (containing the MG190, MG191 and MG192 genes) and its repetitive chromosomal sequences (known as MgPars). The goals of this study were to investigate the location, organization and variability of trinucleotide tandem repeats (TTRs) in the MgPa operon and MgPars and to explore the possible mechanisms and role of TTR variations. By analysing the complete MgPa operon and complete or partial MgPar sequences in a collection of 15 geographically diverse clinical strains of M. genitalium, TTR sequences were identified in four regions in MG191, one region in MG192, and two or three regions in each of all nine MgPars except for MgPar 3. These TTRs were variable not only in the repeat copy number but also in the repeat unit sequence among or within strains. The key mechanisms for the TTR variations likely include recombination between MgPa and MgPars, and slipped-strand mispairing. TTR variation may represent a mechanism to maximize the variation of the MgPa operon, which is complementary to genetic variation involving segmental recombination between MgPa and MgPars, thus enhancing the organism's ability to adhere to and colonize host cells as well as evasion of the host immune system.

Effect of gatifloxacin against Mycoplasma genitalium-related urethritis: an open clinical trial

Objectives

Mycoplasma genitalium and Chlamydia trachomatis are the primary pathogens detected from non-gonococcal urethritis (NGU). In this study, the efficacy of gatifloxacin was examined against M genitalium-related urethritis.

Methods

The study was an open clinical trial evaluating the effectiveness of gatifloxacin with 200 mg doses twice a day for 7 days against male NGU.

Results

Between March and September 2008, 169 male patients were enrolled, and microbiological and clinical cure rates could be evaluated in 86 patients detected with C trachomatis or M genitalium and in 135 with NGU, respectively. Microbiological cure rates of gatifloxacin against C trachomatis and M genitalium were 100% and 83%, respectively, and the total clinical cure rate was 99%.

Conclusion

Analysis of in-vivo and in-vitro data from the literature of fluoroquinolone efficacies against M genitalium suggests that a MIC90 of 0.125 μg/ml or less may be useful for optimal activity against M genitalium infection.

[Usefulness of real-time PCR in detecting Chlamydia trachomatis and Neisseria gonorrhoeae in endocervical swabs and first-voided urine specimens]

We evaluated performance of Abbott RealTime CT/NG assay (real-time PCR, Abbott Japan) for detect Chlamydia trachomatis and Neisseria gonorrhoeae by real-time PCR in 88 female patients with cervicitis symptoms seen at gynecological clinics and 100 male patients with urethritis symptoms seen at urological or dermatology clinics in Kitakyushu, Japan. Endocervical swab and first-voided urine (FVU) specimens were then collected from women and FVU specimens from men. Detection rates of C. trachomatis and N. gonorrhoeae by real-time PCR in the 3 types of specimens were compared to those by ProbeTec ET assay (ProbeTec, BD Diagnostic System). The overall positive concordance between real-time PCR and ProbTec were 97.1% (66/68) for C. trachomatis and 100% (33/33) for N. gonorrhoeae, C. trachomatis detection yielded 3 discordant results in endocervical specimens and 1 discordant result in male FVU by real-time PCR and ProbTec. Three of 4 reexamined using Aptime Combo 2 Assay (Fuji Rebio Inc.) were positive for C. trachomatis. Endocervical swab and FVU specimen results for C. trachomatis were discordant in 3 cases in real-time PCR and 4 in ProbeTec. Subjects with 2 or more positive endocervical awab results in female or male FVU specimens were assumed to be "true positive" for C. trachomatis. The sensitivities of real-time PCR for detecting C. trachomatis was 94.4% in endocervical swabs, 77.8% in female FVU and 97.4% in the male FVU. The sensitivities for real-time PCR for detecting N. gonorrhoeae was 100% in all 3 specimentypes. Abbott RealTime CT/NG assay was useful for detecting C. trachomatis using endocervical swabs or male FVU specimens and for detecting N. gonorrhoeae using endocervical swabs and all FVU specimens.

The nationwide study of bacterial pathogens associated with urinary tract infections conducted by the Japanese Society of Chemotherapy

This study was conducted by the Japanese Society of Chemotherapy and is the first nationwide study on bacterial pathogens isolated from patients with urinary tract infections at 28 hospitals throughout Japan between January 2008 and June 2008. A total of 688 bacterial strains were isolated from adult patients with urinary tract infections. The strains investigated in this study are as follows: Enterococcus faecalis (n = 140), Escherichia coli (n = 255), Klebsiella pneumoniae (n = 93), Proteus mirabilis (n = 42), Serratia marcescens (n = 44), and Pseudomonas aeruginosa (n = 114). The minimum inhibitory concentrations of 39 antibacterial agents used for these strains were determined according to the Clinical and Laboratory Standards Institute (CLSI) manual. All Enterococcus faecalis strains were susceptible to ampicillin and vancomycin. Although a majority of the E. faecalis strains were susceptible to linezolid, 11 strains (7.8%) were found to be intermediately resistant. The proportions of fluoroquinolone-resistant Enterococcus faecalis, Escherichia coli, Proteus mirabilis, and S. marcescens strains were 35.7%, 29.3%, 18.3%, and 15.2%, respectively. The proportions of E. coli, P. mirabilis, K. pneumoniae, and S. marcescens strains producing extended-spectrum β-lactamase were 5.1%, 11.9%, 0%, and 0%, respectively. The proportions of Pseudomonas aeruginosa strains resistant to carbapenems, aminoglycosides, and fluoroquinolones were 9.2%, 4.4%, and 34.8%, respectively, and among them, 2 strains (1.8%) were found to be multidrug resistant. These data present important information for the proper treatment of urinary tract infections and will serve as a useful reference for periodic surveillance studies in the future.

Population-based study of asymptomatic infection with Chlamydia trachomatis among female and male students

There are few epidemiological studies of asymptomatic chlamydial infection among students in non-medical settings with minimal bias and improved accuracy; thus, useful data from screening among students are limited. We aimed to obtain accurate epidemiological information about asymptomatic chlamydial infection among students in non-medical settings. A population-based cross-sectional survey of 10,440 >or=18-year-old asymptomatic students who volunteered for a urine screening test for chlamydia was conducted. The prevalences of asymptomatic infection were 9.5% for women and 6.7% for men. Multivariate analysis revealed the risk factors to be a lifetime history of >or=4 sexual partners for women (odds ratio [OR] 3.17) and inconsistent condom use for men (OR 4.18). For both sexes, younger age at first intercourse was associated with a higher rate of inconsistent condom use. This study produced accurate epidemiological information on asymptomatic chlamydial infection. These results may contribute to the establishment of preventive countermeasures against such infection.

Prevalence of Mycoplasma genitalium among female students in vocational schools in Japan

OBJECTIVE

In Japan it was reported that about 9% of sexually active female teenagers had Chlamydia trachomatis. Most of them were asymptomatic, which may lead to continuing spread of the infection. Like C trachomatis, Mycoplasma genitalium is a pathogen in male non-gonococcal urethritis. However, few studies of the prevalence of M genitalium in the general population have been reported. The objective of this study was to determine the prevalence of M genitalium infection among younger females and to determine risk factors for this infection.

METHODS

The study was conducted between October 2005 and January 2006 using first voided urine specimens and questionnaires from female students of three vocational schools in the Miyazaki prefecture, Japan. C trachomatis was detected with Amplicor PCR. M genitalium was detected with inhibitor controlled real-time TaqMan PCR detecting the MgPa adhesion gene and with a PCR detecting the 16S rRNA. Risk factors associated with infection of M genitalium or C trachomatis were analysed with Fisher's exact test.

RESULTS

Among 298 female, 249 (84%) had had experience of sexual intercourse. The prevalence of M genitalium was 2.8% (95% CI 0.76% to 4.86%) and the prevalence of C trachomatis was 8.8% (95% CI 5.31% to 12.36%).

CONCLUSIONS

The risk factors of infection with M genitalium were more than five lifetime sexual partners and co-infection with C trachomatis.

Usefulness of oral wash specimens for detecting Chlamydia trachomatis from high-risk groups in Japan

Orogenital sex is recognized as a route for the transmission of Chlamydia trachomatis (CT) which thus causes male chlamydial urethritis. Patients with a pharyngeal CT infection have no gross lesions, but CT was tested by pharyngeal swabs. In this study, the usefulness of oral wash specimens for detecting CT was compared to that of swab specimens. In addition, oral wash specimens were also used to screen for CT pharyngeal infection. Eighteen female commercial sex workers in whom CT was detected from pharyngeal swabs were re-examined using both methods. The positive rate for CT was 44% by swabs and 61% by oral wash specimens. Forty-eight male students with CT-positive urine were also screened for pharyngeal CT infection. The positive rates were 6% by swabs and 10% by oral wash specimens. Our findings therefore indicate that oral wash specimens more effectively detected pharyngeal CT infection than pharyngeal swabs.

Enhanced expression of hepatocyte growth factor activator inhibitor type 2-related small peptide at the invasive front of colon cancers

BACKGROUND

Hepatocyte growth factor activator inhibitor type 2-related small peptide (H2RSP) is a small nuclear protein abundantly expressed in the gastrointestinal epithelium. However, its functions remain unknown.

AIMS

To investigate the expression and localisation of H2RSP in normal, injured and neoplastic human intestinal tissue.

METHODS

Immunohistochemical examination and in situ hybridisation for H2RSP were performed using normal and diseased intestinal specimens. Its subcellular localisation and effects on the cellular proliferation and invasiveness were examined using cultured cells.

RESULTS

In the normal intestine, H2RSP was observed in the nuclei of surface epithelial cells and this nuclear localisation was impaired in regenerating epithelium. In vitro, the nuclear translocation of H2RSP was observed along with increasing cellular density, and an overexpression of H2RSP resulted in a reduced growth rate and enhanced invasiveness. H2RSP expression was down regulated in well-differentiated colorectal adenocarcinomas. However, a marked up regulation of the cytoplasmic H2RSP immunoreactivity was observed in cancer cells at the invasive front. These cells showed low MIB-1 labelling, an enhanced p16 expression and nuclear beta-catenin. The number of H2RSP-positive cells in the invasive front of well-differentiated adenocarcinomas was considerably higher in the cases with lymph node metastases than in node-negative ones.

CONCLUSION

In the normal intestine, the nuclear accumulation of H2RSP is a marker of differentiated epithelial cells. Although H2RSP was down regulated in colorectal adenocarcinomas, a paradoxical up regulation was observed in actively invading carcinoma cells. H2RSP immunoreactivity at the invasive front may serve as a marker of invasive phenotype of well-differentiated colon cancers.

Isolation of Mycoplasma genitalium from first-void urine specimens by coculture with Vero cells

Isolation of Mycoplasma genitalium from clinical specimens remains difficult. We describe an improvement of the Vero cell coculture method in which the growth of M. genitalium was monitored by quantitative real-time PCR. Four new M. genitalium strains were isolated from six first-void urine specimens of male Japanese patients with urethritis. In two of them, only M. genitalium was detected: one also contained Ureaplasma urealyticum, and one contained Chlamydia trachomatis, Neisseria gonorrhoeae, U. urealyticum, and Ureaplasma parvum. In the specimens yielding isolates of M. genitalium, growth was documented by quantitative PCR after two to five passages in Vero cells. The complete isolation procedure from the initial inoculation to completion of single-colony cloning took about 1 year. Isolation of M. genitalium from urine specimens proved to be more difficult than from swab specimens. Due to the cytotoxic effect of urine, a procedure involving washing of the urinary sediment was introduced. Furthermore, prolonged storage of the urine specimens before culture was shown to be detrimental to the success of isolation, as shown by the lack of success in attempts to isolate M. genitalium from mailed urine specimens as well as by simulation experiments. High concentrations of penicillin G and amphotericin B were surprisingly inhibitory to the growth of wild-type M. genitalium strains, but penicillin G at 200 IU/ml and polymyxin B at 500 microg/ml could be used as selective antibiotics to avoid bacterial overgrowth in the Vero cell cultures.

Antibiotic susceptibility testing of Mycoplasma genitalium by TaqMan 5' nuclease real-time PCR

Mycoplasma genitalium is an important pathogen in male nongonococcal urethritis (NGU). Isolation of M. genitalium from clinical specimens by axenic culture is very difficult and time-consuming, and very few strains are available for antibiotic susceptibility testing. Primary isolation of M. genitalium by coculture with Vero cells improves the isolation rate significantly. However, some strains cannot be adapted to axenic culture. In this study, we determined the antibiotic susceptibility of M. genitalium strains grown in Vero cell culture with dilutions of antibiotics. Growth of M. genitalium was monitored by a quantitative PCR assay detecting a single-copy region of the mgpB adhesin gene. Growth inhibition in the presence of antibiotics was expressed as a percentage of the DNA load of controls grown in the absence of antibiotics. Eighteen strains were examined, including 6 new strains isolated from urethral swab specimens and 4 new strains isolated from urine specimens collected from Japanese men. Eight strains adapted to axenic culture were also tested by the conventional broth dilution method. The two methods had an acceptable correlation. Azithromycin was the most active drug against M. genitalium. Among the fluoroquinolones, moxifloxacin had the highest activity, with MICs ranging from 0.03 to 0.5 mg/liter, whereas ciprofloxacin and levofloxacin were considerably less active, with MICs ranging from 0.5 to 16 mg/liter and 0.25 to 4 mg/liter, respectively. MICs for tetracycline ranged from 0.125 to 4 mg/liter. This new method could increase the number of M. genitalium strains available for antibiotic susceptibility testing and significantly shorten the time from sampling to MIC results.

Bacteria of preoperative urinary tract infections contaminate the surgical fields and develop surgical site infections in urological operations

BACKGROUND

The risk factors for surgical site infection (SSI) following urological operations have not been clearly identified, although the presence of a preoperative urinary tract infection (UTI) is thought to be one risk factor. We studied potential risk factors to clarify when and how bacteria contaminate wounds and SSI develop.

METHODS

Objects of the present study were patients with SSI after open urological operations that were performed at the Department of Urology, Miyazaki Medical College Hospital, University of Miyazaki, Kiyotake, Miyazaki, Japan, during the period between June 1999 and December 2000. Endourological operations, operations on children and short operations of less than 2 h duration were excluded. Patients were screened for the presence of UTI before the operation and subcutaneous swabs for culture were collected at the end of the operation by brushing with a sterile cotton-swab just before skin closure.

RESULTS

Surgical site infections occurred in 20 of 134 patients. Bacteria from the subcutaneous swabs were detected in 15 (75.0%) of the patients with SSI. All patients received antimicrobial prophylaxis (AMP), but bacteria from the subcutaneous swabs of patients with SSI were less susceptible to the agents (20.0%). Preoperative UTI were observed in 11 (55.0%) of the patients with SSI. In these patients, four had the same species of bacteria detected from urine, swab and wound, three had the same species from swab and wound and one had the same species from urine and wound.

CONCLUSIONS

Preoperative UTI was the most important risk factor for SSI following urological operations. It is most likely that the bacteria in the urine contaminated the surgical fields and the AMP resistant strains produced SSI.

Prevalence and risk factors of asymptomatic chlamydial infection among students in Japan

The objective was to determine the prevalence of asymptomatic Chlamydia trachomatis infection (CTI) among students in Japan, and to examine risk factors and methods of prevention. A total of 1004 students were analysed. Urine samples were checked for chlamydial DNA using polymerase chain reaction techniques. Prevalence of CTI was 8.3%. Risk factors were age and a history of four or more sexual partners for females, and history of CTI and contact with new sexual partners for males. Age did not represent a risk factor for male students. A correlation was identified between history of genital infection and experience with commercial sex workers for male students. Sex education programmes should be implemented encouraging use of condoms not only by students over 18 years, but also by senior high school students. Development of efficient and practical screening systems tailored to the current status of school health management in Japan is also needed.

[Recurrence of vesicoureteral reflux detected 19 years after ureterocystoneostomy: a case report]

A 21-year-old male, who had been operated on for bilateral vesicoureteral refluxes (VURs) with bilateral ureterocystoneostomy (Politano-Leadbetter's method) 19 years before, was admitted to our hospital due to recurrent VUR. Since the former operation, he had undergone voiding cystography (VCUG) twice for two years, and no refluxes were found. Moreover, no evidence of upper urinary tract deterioration was found by either intravenous pyelography (IVP) or renal ultrasound scanning taken the year before this admission. Nineteen years after the operation, the dilation of the left lower ureter was found on IVP and, consequently, he suffered from pyelonephritis. The VCUG revealed the recurrence of left VUR. Because of his allergic reaction to collagen, we again performed left ureterocystoneostomy (Politano-Leadbetter's method). At three months postoperatively, there was no VUR found on VCUG.

Reduced expression of hepatocyte growth factor activator inhibitor type-2/placental bikunin (HAI-2/PB) in human glioblastomas: implication for anti-invasive role of HAI-2/PB in glioblastoma cells

Hepatocyte growth factor activator inhibitor type-2/placental bikunin (HAI-2/PB) is a serine proteinase inhibitor that contains 2 Kunitz-domains and a presumed transmembrane domain. It has broad inhibitory spectra against various serine proteinases showing potent inhibitory activities not only to hepatocyte growth factor activator but also to plasmin, trypsin and kallikreins. In this study, we investigated the expression of HAI-2/PB in human gliomas in vivo and the effects of HAI-2/PB on the fibrinolytic and invasive capabilities of human glioblastoma cells in vitro. With RNA blot analysis, HAI-2/PB mRNA was expressed in normal brain and in low-grade astrocytomas, but was hardly detectable in anaplastic astrocytomas and glioblastomas, indicating that its expression levels were inversely correlated with the histological grade of human gliomas. To further explore the possible role of HAI-2/PB in glioma progression, cultured human glioblastoma cell lines (U251 and YKG-1) were transiently transfected with an expression vector harboring human HAI-2/PB cDNA. Subsequent analysis indicated that the expression of HAI-2/PB suppressed the fibrinolytic activities of both glioblastoma cell lines. Moreover, HAI-2/PB inhibited Matrigel invasion of U251 and YKG-1 cells by 30% and 64%, respectively. This anti-invasive effect appeared to be mediated primarily by the inhibitory activity of HAI-2/PB against the serine proteinase-dependent matrix degradation. These findings suggest that the reduced expression of HAI-2/PB is possibly involved in the progression of human gliomas.

Mouse hepatocyte growth factor activator inhibitor type 1 (HAI-1) and type 2 (HAI-2)/placental bikunin genes and their promoters

Hepatocyte growth factor (HGF) activator inhibitor type 1 (HAI-1) and type 2 (HAI-2) were recently discovered as specific inhibitors of HGF activator. Each of them contains two Kunitz-type serine protease inhibitor domains and a transmembrane domain, so that their overall structures are similar to each other. In this study, mouse genes encoding HAI-1 and HAI-2 were cloned by screening of a mouse genomic bacterial artificial chromosome library and by polymerase chain reaction of mouse genomic DNA, respectively. The genes (mHAI-1 and mHAI-2) were defined to consist of 11 and eight exons spanning 11 kbp and 9.5 kbp, respectively. Neither a TATA nor CAAT box was found in 5'-flanking regions of both genes and no apparent homologous portion was observed between mHAI-1 and mHAI-2 promoter regions. Promoter assay of mHAI-1 and human HAI-1 revealed that the potential binding sites of a complex of Egr-1-3 and Sp1, which was well-conserved between human (-42 to -58) and mouse (-44 to -57), might be a key portion of its transcriptional regulation to function as not only house-keeping but also early responsive genes.

Pericellular activation of hepatocyte growth factor/scatter factor (HGF/SF) in colorectal carcinomas: roles of HGF activator (HGFA) and HGFA inhibitor type 1 (HAI-1)

Activation of hepatocyte growth factor/scatter factor (HGF/SF) is a critical limiting step in the HGF/SF-induced signaling pathway mediated by MET receptor tyrosine kinase. Although HGF/SF-MET signaling could have potentially important roles in the invasive growth of tumors and tumor angiogenesis, little is known about the regulation of HGF/SF activation in the tumor tissues. This activation occurs in the extracellular milieu caused by proteolytic cleavage at the bond between Arg194-Val195 in the single-chain HGF precursor to generate the active two-chain heterodimeric form. Here we show that activation of HGF/SF is significantly enhanced in colorectal carcinoma tissues compared with normal colorectal mucosa, and HGF activator (HGFA), a recently identified factor XII-like serine proteinase, is critically involved in this process. Furthermore, we also show that HGF activator inhibitor type 1 (HAI-1) should have an important regulatory role in the pericellular activation of HGF/SF having diverse roles acting as a cell surface specific inhibitor of active HGFA and a reservoir of this enzyme on the cell surface. The latter property might paradoxically ensure the concentrated pericellular HGFA activity in certain cellular conditions in which shedding of HAI-1/HGFA complex from the plasma membrane is upregulated.

Simultaneous up-regulation of urokinase-type plasminogen activator (uPA) and uPA receptor by hepatocyte growth factor/scatter factor in human glioma cells

Several lines of evidence indicate that hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, c-Met, may play an important role in progression of human glioma. In this study, effects of HGF/SF on urokinase- type plasminogen activator (uPA)-mediated proteolysis network were examined in c-Met-positive human glioma cell lines. Treatment of the glioma cells with various concentrations of HGF/SF resulted in an enhanced secretion of uPA proteins accompanying increased transcription of uPA mRNA in a dose dependent fashion. The levels of uPA receptor (uPAR) mRNAs were also elevated simultaneously upon HGF/SF stimulation, and the cell-surface associated uPA activity was also elevated by the treatment. Since concomitant expression of HGF and its receptor c-Met are frequently observed in malignant gliomas, these results suggest that HGF/SF participates in invasive process of malignant glioma cells not only by its motility-stimulating activity but also through enhanced degradation of the extracellular matrix induced by autocrine activation of uPA proteolysis network.

[Small cell carcinoma of the prostate: a case report]

A 81-year-old man was admitted to our department with the chief complaints of pollakisuria and difficulty in voiding. He presented with increased serum PSA level (over 100 ng/ml). We performed biopsy of the prostate and found a moderately differentiated adenocarcinoma. Various urological examinations showed metastases to paraaortic lymph nodes and systemic bones. He was started-on hormonal therapy. Nine months from the start of hormonal therapy, this therapy was effective and the serum PSA level was decreased to 14 ng/ml. Thereafter, the serum PSA level and the tumor volume were increased and he died 29 months from the start of treatment. The autopsy revealed small cell carcinoma with adenocarcinoma of the prostate.

Hepatocyte growth factor activator inhibitor type 1 is a specific cell surface binding protein of hepatocyte growth factor activator (HGFA) and regulates HGFA activity in the pericellular microenvironment

Hepatocyte growth factor activator (HGFA) is responsible for proteolytic activation of the precursor form of hepatocyte growth factor in injured tissues. To date, two specific inhibitors of HGFA have been identified, namely HGFA inhibitor type 1 (HAI-1) and type 2 (HAI-2)/placental bikunin (PB). Both inhibitors are first synthesized as integral membrane proteins having two Kunitz domains and a transmembrane domain, and are subsequently released from cell surface by shedding. Here we show that an active form of HGFA is specifically complexed with membrane-form HAI-1, but not with HAI-2/PB, on the surface of epithelial cells expressing both inhibitors. This binding required the enzyme activity of HGFA. The selective binding of HGFA to the cell surface HAI-1 was further confirmed in an engineered system using Chinese hamster ovary cells, in which only the cells expressing HAI-1 retained exogenous HGFA. The binding of HGFA to HAI-1 was reversible, and no irreversible modifications affecting the enzyme activity occurred during the binding. Importantly, HAI-1 and the HGFA.HAI-1 complex were quickly released from the cell surface by treatment with phorbol 12-myristate 13-acetate or interleukin 1beta accompanying the generation of 58-kDa fragments of HAI-1, which are less potent against HGFA, as well as significant recovery of HGFA activity in the culture supernatant. This regulated shedding was completely inhibited by BB3103, a synthetic zinc-metalloproteinase inhibitor. We conclude that HAI-1 is not only an inhibitor but also a specific acceptor of active HGFA, acting as a reservoir of this enzyme on the cell surface. The latter property appears to ensure the concentrated pericellular HGFA activity in certain cellular conditions, such as tissue injury and inflammation, via the up-regulated shedding of HGFA.HAI-1 complex. These findings shed light on a novel function of the integral membrane Kunitz-type inhibitor in the regulation of pericellular proteinase activity.

Localization of hepatocyte growth factor activator inhibitor type 1 in Langhans' cells of human placenta

Activation of hepatocyte growth factor (HGF) is a crucial limiting step in HGF-induced signaling pathway. The HGF activator inhibitor type 1 (HAI-1) was identified as a potent inhibitor of HGF activator (HGFA), a serine proteinase that is responsible for the activation of HGF in vivo. HAI-1 is an integral membrane Kunitz-type serine proteinase inhibitor, and its mRNA has been reported to be most abundant in the placenta. In this report, specific antibody to HAI-1 was used in an immunohistochemical procedure to determine the localization of HAI-I in human placenta. HAI-1 was expressed in cytotrophoblasts (Langhans' cells) of the double-layered trophoblastic epithelium of chorionic villi tissue, and syncytiotrophoblasts were almost negative. On the other hand, extravillous trophoblasts of cytotrophoblastic columns showed markedly decreased immunoreactivity, and those infiltrating into the superficial decidua membrane of early placenta were hardly stainable. The amnionic epithelial cells were also immunostained intensely. The presence of HAI-1 mRNA was also confirmed in a cultured human cytotrophoblastic cell line. In addition to HAI-1, low but distinct expression of HGFA mRNA was observed in the placenta tissue and cultured cytotrophoblasts by using a sensitive RT-PCR method. Since HGF plays an essential role in the placenta development, expression of HAI-1 and HGFA may have an important regulatory role in the placenta. The localization of HAI-I in the proliferating trophoblastic stem cells (Langhans' cells), but not in syncytiotrophoblasts and extravillous trophoblasts, suggest a possible role of HAI-1 in the proliferation of trophoblasts.

Activation of hepatocyte growth factor/scatter factor in colorectal carcinoma

Activation of hepatocyte growth factor/scatter factor (HGF/SF) in the extracellular milieu is a critical limiting step in the HGF/SF-induced signaling pathway mediated by Met receptor tyrosine kinase, which has potentially important roles in tumor biology and progression. However, little is known concerning the regulation of HGF/SF activation in tumors. Immunoblot analysis revealed that the activation of HGF/SF was enhanced significantly in colorectal carcinoma tissues compared with the corresponding normal mucosa. Serum-free conditioned media of cultured human colorectal carcinoma cell lines contained HGF/SF-activating activity, and the addition of a single-chain precursor form of HGF/SF to the serum-free culture of these cells resulted in HGF/SF-dependent modulation of cellular phenotypes, such as increased scattering and enhanced secretion of vascular endothelial growth factor. This processing activity was enhanced by thrombin treatment but was inhibited significantly by a neutralizing antibody against HGF activator (HGFA), a factor XIIa-like serine proteinase believed to be expressed mainly in the liver. The activity was also inhibited by recombinant HGFA inhibitor type 1 (HAI-1). The presence of HGFA mRNA and secretion of HGFA protein were confirmed in the cell lines. Therefore, extrahepatic expression of HGFA in the colorectal carcinoma cells could be responsible for the single-chain HGF/SF-processing activity of the cells. We examined the expression of HGFA and HAI-1 in human colorectal mucosa and adenoma-carcinoma sequence. Immunohistochemically, HGFA was stained weakly in the normal enterocytes, and immunoreactivity was increased modestly in the neoplastic differentiation. The subcellular localization of HGFA immunoreactivity was altered in carcinoma cells showing basal or cell-stroma interface staining patterns, compared with normal and adenoma cells with a supranuclear or apical staining pattern. In contrast to HGFA, the expression of HAI-1 decreased significantly in carcinoma cells relative to the adjacent normal or adenoma cells, indicating that the net balance between HGFA and HAI-1 shifts in favor of HGFA in carcinomas. In fact, pro-HGFA and the active form of HGFA proteins increased in carcinoma tissue compared with the corresponding normal mucosa. It was concluded that HGFA is expressed in colorectal mucosa and tumors and could be involved in the activation of HGF/SF in colorectal carcinomas. Therefore, the balance between HGFA and HAI-1 could play an important role in the regulation of HGF/SF activity in colorectal carcinomas.

Genomic structure and chromosomal localization of the human hepatocyte growth factor activator inhibitor type 1 and 2 genes

Hepatocyte growth factor activator inhibitor type 1 (HAI-1) and type 2 (HAI-2) are recently discovered Kunitz-type serine protease inhibitors which can be purified and cloned from human stomach cancer cell line MKN45 as specific inhibitors against hepatocyte growth factor activator (HGFA). HAI-2 was identical with the protein originally reported as placental bikunin. Both proteins contain two Kunitz inhibitor domains (KDs), of which the first domain (KD1) is mainly responsible for the inhibitory activity against HGFA, and are expressed ubiquitously in various tissues. In this study, we cloned the genes coding for these two structurally similar proteins by screening of human genomic bacterial artificial chromosome (BAC) library and their genomic structures were compared. HAI-1 and -2 genes consist of 11 and 8 exons spanning 12 kbp and 12.5 kbp, respectively. Three exons were inserted between KD1 and KD2 of each gene, of which the middle one was the low-density lipoprotein (LDL) receptor-like domain (HAI-1) and the testis specific exon (HAI-2). Apparently homologous regions between HAI-1 and -2 were not found in 5'-flanking region and neither TATA nor CAAT box was present. The genes were mapped to chromosome 15q15 (HAI-1) and 19q13.11 (HAI-2). These results suggested that although HAI-1 and -2 genes might be derived from same ancestor gene, they acquired distinctive in vivo roles during their evolution.

Carcinoembryonic antigen and carbohydrate antigen 19-9-producing adenocarcinoma of the prostate: report of an autopsy case

Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) are well known as specific tumor markers of prostate cancer, but carcinoembryonic antigen (CEA)- and carbohydrate antigen 19-9 (CA19-9)-producing adenocarcinoma originating in the prostate is rare. We report here a case of prostatic adenocarcinoma positive for these 4 tumor markers in a 50-year-old man who had initially complained about chest pain due to metastatic bone tumor. In spite of the extensive treatment involving hormone and radiation therapy, the patient died of rapid tumor extension only 4 months after initial diagnosis. Autopsy revealed multiple metastases to the bone, liver, lungs and lymph nodes. Histologically, two types of adenocarcinoma were involved in both primary prostate and metastatic sites: one was a poorly differentiated adenocarcinoma positive for PSA and PAP but not CEA or CA19-9, and the other one was a less differentiated adenocarcinoma partially positive for CEA and CA19-9 but not for PSA or PAP. Based on this case and previous cases by review of the literature, CEA- and CA19-9-producing adenocarcinoma of the prostate was suggested to rapidly progress with multiple metastases and to show poor prognosis with strong resistance to any treatment.

Mouse hepatocyte growth factor activator gene: its expression not only in the liver but also in the gastrointestinal tract

A cDNA encoding mouse hepatocyte growth factor activator (HGFA) has been cloned by RT-PCR, based on the screening result from the database of expressed sequence tags. Subsequently, its gene was cloned from a mouse genomic bacterial artificial chromosome library using the cDNA as a probe. Sequencing analysis revealed that mouse HGFA protein deduced from the cDNA, similar to its human and rat counterparts, has two epidermal growth factor-like domains, type 1 and 2 fibronectin homology domains, a single kringle domain and a catalytic domain of serine proteinase, and the gene consists of 14 exon spanning approximately 7.5 kb. Interestingly, mouse HGFA mRNA was detected not only in the liver but also in the gastrointestinal tract by RNA blot analysis. Since hepatocyte growth factor (HGF) is up-regulated in the damaged gastrointestinal mucosa, our present data suggest that HGFA might activate proHGF directly in the gastrointestinal mucosa and play an important role in wound repair throughout the gastrointestinal tract.

Upregulation of HGF activator inhibitor type 1 but not type 2 along with regeneration of intestinal mucosa

Hepatocyte growth factor (HGF) activator inhibitor type 1 (HAI-1) and type 2 (HAI-2) are new Kunitz-type serine protease inhibitors that were recently purified and cloned from the human stomach cancer cell line MKN45 as specific inhibitors against HGF activator. Both proteins contain two Kunitz inhibitor domains and are expressed abundantly throughout the gastrointestinal tract, in addition to the placenta, pancreas, and kidney. In this study, to assess the possible roles of HAI-1 and HAI-2 in the intestinal mucosa, we examined the expression of HAI-1 and HAI-2 during regeneration of the intestinal mucosa. Immunohistochemical studies revealed that HAI-1 but not HAI-2 was detected more strongly in regenerative epithelium than in normal epithelium, although both proteins were detected throughout the human gastrointestinal tract. During the course of acetic acid-induced experimental colitis in an in vivo mouse model, HAI-1 but not HAI-2 was upregulated in the recovery phase, suggesting that HAI-1 but not HAI-2 is associated with the regeneration of damaged colonic mucosa. Upregulation of HAI-1 may serve to downregulate the proliferative response after initial activation of MET receptor by HGF/scatter factor after an injury.

Conserved expression of hepatocyte growth factor activator inhibitor type-2/placental bikunin in human colorectal carcinomas

Hepatocyte growth factor activator inhibitor type 2 (HAI-2) was recently identified as a potent inhibitor of hepatocyte growth factor activator. It was also independently reported as placental bikunin (PB) and as a protein over-expressed in pancreatic cancer. The expression of HAI-2/PB was analyzed in human normal colon mucosa, adenomas, and carcinomas. HAI-2/PB mRNA was consistently expressed in the colorectal mucosa. The expression was conserved in the neoplastic colorectal mucosa, and no relationship was found between HAI-2/PB mRNA levels and tumor stages. Moreover, 13 out of 14 colorectal carcinoma cell lines expressed HAI-2/PB mRNA. Immunohistochemically, HAI-2/PB proteins were predominantly stained beneath the apical surface of normal enterocytes. In tumor tissues, rather disarranged intracytoplasmic granular staining was observed. The HAI-2/PB immunoreactivity was well conserved in the colonic adenoma-carcinoma sequence, and this protein may have important unknown function in the intestinal mucosa.

Overexpression of intestinal trefoil factor in human colon carcinoma cells reduces cellular growth in vitro and in vivo

BACKGROUND & AIMS

Intestinal trefoil factor (ITF) has a role in gastrointestinal mucosal integrity and the repair of damaged mucosa. However, little is known about its role in tumors. To analyze the role of ITF in colon carcinomas, overexpression of the ITF gene in colon carcinoma cells was used.

METHODS

Human colon carcinoma cell lines LoVo and SW837, expressing no endogenous ITF, and WiDr expressing a low level of ITF were stably transfected with an expression vector harboring human ITF complementary DNA. The effects of ITF overexpression on in vitro growth, morphology in collagen gel, response to epidermal growth factor (EGF), mitogen-activated protein kinase (MAPK) activity, and growth in nude mice were assessed.

RESULTS

Overexpression of ITF in LoVo and SW837 resulted in significantly reduced growth in vitro and in vivo. In collagen gels, the ITF-expressing LoVo clones formed smaller, more dispersed colonies. EGF-induced phosphorylation of MAPKs was modestly reduced in the ITF-expressing clones. The growth of WiDr was modestly suppressed only in vivo by ITF overexpression.

CONCLUSIONS

Overexpression of ITF suppressed the growth of colon carcinoma cells. ITF may function as an inhibitory factor for the growth of colonic neoplasm.

[Acute renal failure due to over-infusion in a child with bilateral obstruction of the pyeloureteral junction]

A 2-year-old boy was hospitalized with the chief complaint of oliguria and dyspnea. Bilateral hydronephrosis and obstruction of the pyeloureteral junction were detected by ultrasonography. Pulmonary edema was also found on chest radiographs. The clinical diagnosis was acute post renal failure due to bilateral pyeloureteral obstruction and pulmonary edema due to overtransfusion. After we performed bilateral percutaneous nephrostomy, the patient recovered from renal failure and pulmonary edema. Both nephrostomies were removed after we confirmed a non-obstructing pattern using the Whitaker test.

Solitary fibrous tumor of the spinal nerve rootlet: case report and literature survey

Solitary fibrous tumor (SFT) is a rare tumor that arises most commonly in the pleura. Recent evidence indicated that it is a tumor that originates from mesenchymal, probably fibroblastic, cells and is not restricted to the pleura. This report presents a case of primary SFT occurring as a dumbbell-shaped tumor of the cervical spine (C4/5) in a 46-year-old Japanese female, probably originating from the spinal rootlet. The tumor was predominantly extradural, loosely attached to the dura mater, with a small intradural extramedullary part attached to the C5 anterior and posterior rootlets. Histologically, the tumor was predominantly composed of a haphazard proliferation of spindle cells separated by abundant collagen. Immunohistochemically, the cells were strongly positive for CD34, bcl-2 and vimentin, but were negative for S-100 protein, neuron specific enolase, cytokeratin and epithelial membrane antigen. The present case and review of the literature strongly suggest that SFT is an entity that should be considered in the differential diagnosis of tumors of the cerebrospinal region.

Regulation of matrix metalloproteinase-2 (MMP-2) by hepatocyte growth factor/scatter factor (HGF/SF) in human glioma cells: HGF/SF enhances MMP-2 expression and activation accompanying up-regulation of membrane type-1 MMP

Hepatocyte growth factor/scatter factor (HGF/SF) contributes to the malignant progression of human gliomas. We investigated the effect of HGF/SF on matrix metalloproteinase-2 (MMP-2), membrane type 1 matrix metalloproteinase (MT1-MMP) and tissue inhibitors of metalloproteinases (TIMPs), expressions of c-Met/HGF receptor-positive human glioblastoma cells. Treatment of U251 human glioblastoma cells with HGF/SF resulted in enhanced secretion of MMP-2 with an increased level of the active form. This was accompanied by enhanced expression (2.5-fold) of mRNA specific for MMP-2. The stimulatory effect of HGF/SF on MMP-2 expression did not occur in the presence of herbimycin A, a protein tyrosine kinase inhibitor. MT1 -MMP, a cell-surface activator of proMMP-2, was also up-regulated by HGF/SF in a dose-dependent manner. By contrast, the level of TIMP- 1 mRNAs was not altered significantly and that of TIMP-2 was reduced mildly by the HGF/SF treatment, suggesting that HGF/SF may eventually modulate a balance between MMP-2 and TIMPs in favor of the proteinase activity in the glioma cell microenvironment. HGF/SF also stimulated MMP-2 expression of other glioblastoma cell lines. Since glioblastomas frequently co-express HGF/SF and its receptor, our results suggest that HGF/SF might contribute to the invasiveness of glioblastoma cells through autocrine induction of MMP-2 expression and activation.

Regulation of matrix metalloproteinase-2 (MMP-2) by hepatocyte growth factor/scatter factor (HGF/SF) in human glioma cells: HGF/SF enhances MMP-2 expression and activation accompanying up-regulation of membrane type-1 MMP

Hepatocyte growth factor/scatter factor (HGF/SF) contributes to the malignant progression of human gliomas. We investigated the effect of HGF/SF on matrix metalloproteinase-2 (MMP-2), membrane type 1 matrix metalloproteinase (MT1-MMP) and tissue inhibitors of metalloproteinases (TIMPs), expressions of c-Met/HGF receptor-positive human glioblastoma cells. Treatment of U251 human glioblastoma cells with HGF/SF resulted in enhanced secretion of MMP-2 with an increased level of the active form. This was accompanied by enhanced expression (2.5-fold) of mRNA specific for MMP-2. The stimulatory effect of HGF/SF on MMP-2 expression did not occur in the presence of herbimycin A, a protein tyrosine kinase inhibitor. MT1 -MMP, a cell-surface activator of proMMP-2, was also up-regulated by HGF/SF in a dose-dependent manner. By contrast, the level of TIMP- 1 mRNAs was not altered significantly and that of TIMP-2 was reduced mildly by the HGF/SF treatment, suggesting that HGF/SF may eventually modulate a balance between MMP-2 and TIMPs in favor of the proteinase activity in the glioma cell microenvironment. HGF/SF also stimulated MMP-2 expression of other glioblastoma cell lines. Since glioblastomas frequently co-express HGF/SF and its receptor, our results suggest that HGF/SF might contribute to the invasiveness of glioblastoma cells through autocrine induction of MMP-2 expression and activation.

Hepatocyte growth factor activator inhibitor type 2 lacking the first Kunitz-type serine proteinase inhibitor domain is a predominant product in mouse but not in human

Hepatocyte growth factor activator inhibitor type 2 (HAI-2) is a new Kunitz-type serine protease inhibitor, which is purified and cloned from human stomach cancer cell line MKN45. The mature HAI-2 protein contains two Kunitz domains and the first domain is mainly responsible for the inhibitory activity against hepatocyte growth factor activator (HGFA). In this study, we identified the mouse homolog of HAI-2 (mHAI-2) by screening the data base of public expressed sequence tag (dbEST). In addition to a full-length cDNA corresponding to human HAI-2, a shorter size of mHAI-2 cDNA was obtained from mouse kidney by reverse-transcription polymerase chain reaction (RT-PCR). Sequence analysis of this shorter cDNA revealed that the region encoding the first Kunitz domain was completely deleted. Analysis of mouse genomic DNA showed that the deleted cDNA was generated by an alternative splicing mechanism. Surprisingly, the spliced form lacking the first Kunitz domain was a predominant transcript in all tissues of mice tested but not in those of human as assessed by RT-PCR analysis. This phenomenon is also confirmed by Western blot analysis using the specific antiserum against human HAI-2 protein. These results suggest that most of HAI-2 expressed in various tissues of mice may be unable to inhibit HGFA efficiently.

Retroperitoneal bronchogenic cyst: report of a case and literature review

A large cystic mass was found in the subdiaphragmatic region of a 46-year-old woman who had complained of continuous pain in the left flank . The cyst was located in the retroperitoneum just below the diaphragm and was adhered to the diaphragmatic skeletal muscle and abdominal aorta, but was separate from the spleen, pancreas, left adrenal gland and left kidney. The surgically resected cyst measured 8 x 8 x 7 cm and was filled with protein-rich fluid, which contained amylase and embryonal proteins such as carcinoembryonic antigen, CA125 and CA19-9. Histologically, the cyst wall was composed of a fibrovascular connective tissue containing thin smooth muscle layers and mucus-secreting glands and was lined by a ciliated pseudostratified or tall columnar epithelium without dysplastic changes. Thus, a diagnosis of bronchogenic cyst, which is usually discovered in the posterior part of the mediastinum, was made. A rare case of bronchogenic cyst and a literature review is presented.

Up-regulation of vascular endothelial growth factor induced by hepatocyte growth factor/scatter factor stimulation in human glioma cells

Recent findings suggest that hepatocyte growth factor/scatter factor (HGF/SF) contributes to the malignant progression of human gliomas. We investigated the effect of HGF/SF on vascular endothelial growth factor (VEGF) expression of c-Met/HGF receptor-positive human glioma cell lines. Treatment of the glioma cells with various concentrations of HGF/SF resulted in an enhanced secretion of VEGF proteins accompanying increased transcription of VEGF mRNA in a dose-dependent fashion. Since malignant gliomas frequently co-express HGF/SF and its receptor, these results suggest that HGF/SF could act as an indirect angiogenic factor through autocrine induction of VEGF expression and secretion in malignant gliomas.