Impact of Helicobacter pylori infection on gastric cancer incidence in a general Japanese population: the Hisayama study

BACKGROUND

Several nested case-control studies have reported the potentially causal relationship between Helicobacter pylori infection and the development of gastric cancer. However, there has been no prospective study evaluating this issue. The purpose of this study is to examine the impact of H pylori infection on gastric cancer occurrence in a general Japanese population (Hisayama, Japan) stratified according to sex, using a prospective study design.

METHODS

A total of 2602 subjects aged 40 years or older (1070 men; mean age, 57 years; 1532 women; mean age, 59 years) without a history of gastrectomy or gastric cancer were classified according to the status of the serum IgG antibodies to H pylori and observed prospectively for 9 years from 1988.

RESULTS

Infection of H pylori was more common in men (71.5%) than in women (62.5%; P<.001). The age-adjusted incidence of gastric cancer for men (5.3 per 1000 person-years) was 4-fold higher than that for women (1.3; P<.001). In men, the age-adjusted incidence of gastric cancer was significantly higher in the subjects with H pylori infection than in those without it (6.2 vs 2.5; relative risk, 2.59 [95% confidence interval, 1.03-6.50]), whereas no significant difference was observed in women (1.2 vs 1.1; relative risk, 0.99 [95% confidence interval, 0.36-2.68]). These results were similar even after controlling for other risk factors in multivariate analysis. It was estimated that 40.1% of gastric cancers for men in this cohort were attributable to H pylori infection.

CONCLUSION

A significant relationship exists between infection with H pylori and subsequent occurrence of gastric cancer for men but not for women in this Japanese population.

Coreceptor function of mutant human CD4 molecules without affinity to gp120 of human immunodeficiency virus

Despite extensive mutational studies on the human CD4 molecule and its affinity to human immunodeficiency virus (HIV) envelope glycoprotein gp120, coreceptor functions of such mutant molecules have only been examined by indirect measurement of their affinity to class II major histocompatibility complex (MHC) molecules. In this report, coreceptor functions of mutant human CD4 molecules, which have no or reduced affinity to an HIV envelope protein, gp120, were assessed in a murine T cell receptor/class II MHC recognition system. The substitution of human C" beta strand with the murine homologous segment resulted in the loss of the coreceptor function as well as in the complete loss of gp120 binding capacity, corroborating the consensus that Phe-43 in C" beta strand plays crucial roles in both situations. However, simultaneous replacement of the C'-C" loop along with the C" beta strand by homologous murine segments rescued the coreceptor function, whereas gp120 binding capacity remained negative. Further analysis indicated that insertion of lysine between Gly-41 and Ser-42 can partially compensate for the coreceptor function lost by the Phe-43 --> Val mutation. Although the coreceptor function of these mutant CD4 molecules in a human T cell recognition system is yet to be determined, these observations necessitate a re-evaluation of the role played by Phe-43 in coreceptor function. Examination of the sensitivities of the mutant CD4 molecules expressed on HeLa cells to infection by a T cell-tropic HIV-1 strain indicated that only those mutants that had completely lost gp120 binding capacity were resistant to the infection. All mutants having whole C" substitution, irrespective of additional substitutions or their coreceptor functions, were resistant to the infection.

Cell death-associated translocation of plasma membrane components induced by CTL

In the very early stages of target cell apoptosis induced by CTL, we found that fluorescence of labeling probes of the target plasma membrane, such as N-(3-triethylammoniumpropyl)-4-(p-dibutylaminostyryl)pyridin ium dibromide (FM1-43), was translocated into intracellular membrane structures including nuclear envelope and mitochondria. This translocation was associated with the execution of CTL-mediated killing, because neither the CTL-target conjugation alone nor the binding of noncytotoxic Th2 clone with target cell was sufficient to provoke the process. Although FM1-43 translocation was observed in perforin-mediated cytotoxicity, examinations with several other dyes failed to detect the evidence for membrane damages that may cause influx of the dye. Moreover, the translocation was also observed in Fas-dependent apoptosis. These data indicate that the translocation precedes the damage of plasma membrane and intracellular organella in the course of apoptotic cell death and may represent the existence of a membrane trafficking that mediates the translocation of plasma membrane components in the early onset of apoptotic cell death.

The relationship between technical parameters of external beam radiation therapy and complications for localized prostate cancer

BACKGROUND

This study was performed to review retrospectively the clinical course of chronic rectal bleeding as a complication of external beam radiation therapy for localized prostate cancer and to analyze the relationship between technical parameters of radiation therapy and the complications.

METHODS

Seventy-one patients with stages A2, B and C were treated with local-field radiotherapy (total dose 52.5-66 Gy, daily dose 2.0-3.28 Gy, field area 30-81 cm2, number of fields 3-15 ports, planning simulations X-ray or CT-based) between 1989 and 1998 at three institutions. The protocols were consistent during this same period at these institutions.

RESULTS

Multivariate analysis revealed pretreatment PSA and Gleason sum to be statistically significant predictors of 5 year prostatic specific antigen (PSA) relapse-free rates in a median follow-up period of 42 months (range 12-119 months). The significant risk factors for higher grading of acute morbidity were a biological equivalent dose, alpha/beta = 10(BED10) > or =65 Gy, dose per fraction > or =3.0 Gy, field area > or =42 cm2, fewer ports and X-ray planning simulation. However, no parameter was associated with higher grading of late morbidity. Eleven patients (15.4%) experienced a late GI complication: grade 1 (4.2%), grade 2 (9.8%), grade 3 (1.4%). The median time to occurrence of rectal bleeding was 12 months after radiotherapy and the mean duration of morbidity was 11 months.

CONCLUSIONS

Higher total dose and dose per fraction, larger field area, fewer ports and X-ray simulation increased the grades of acute morbidity. A majority of chronic rectal bleedings were transient and responded to conservative treatment.

Significance of the Grb2 and son of sevenless (Sos) proteins in human bladder cancer cell lines

The epidermal growth factor (EGF) receptor has been suggested to have an important role in tumor initiation and progression of human bladder cancers. Grb2 protein, which is the downstream effector of the EGF receptor, acts as an adaptor protein between the EGF receptor and the Ras guanine-nucleotide exchange factor, son of sevenless (Sos) protein. Sos protein regulates the action of Ras protein by promoting the exchange of GDP for GTP. However, the significance of Grb2 and Sos proteins, which is related to EGF-triggered Ras activation, has not been elucidated in human bladder cancer. The aim of the present study is to clarify the significance of these proteins in human bladder cancer cell lines. In the present study, we used four human bladder cancer cell lines (T24, KU-7, UMUC-2, UMUC-6) and two kinds of cultured normal urothelial cells (HMKU-1, HMKU-2) isolated from patients with no malignancy. We examined the expression of EGF receptor, Grb2, and Sos proteins in these cells by Western blot analysis. Furthermore, the bladder cancer cell lines were subjected to sequence analysis to identify a point mutation in the c-H-ras gene at codon 12. There was no marked difference in the expression of the EGF receptor between human bladder cancer cell lines and cultured normal urothelial cells. On the other hand, expression of Grb2 and Sos proteins was substantially increased in all human bladder cancer cell lines examined in comparison with cultured normal urothelial cells, whether codon 12 of H-ras was mutated or not. These results suggest that the amplification of both Grb2 and SOS proteins plays an important role in the carcinogenesis of human bladder cancer.

Isolation of a vascular cell wall-specific monoclonal antibody recognizing a cell polarity by using a phage display subtraction method

Using a strategy consisting of (i) the isolation of cell walls from synchronously differentiating cells of Zinnia, (ii) the generation of mAbs with an antibody phage display method, and (iii) screening with a subtraction method, we isolated mAbs recognizing vascular development-specific cell wall components without prior antigen identification. One of the isolated mAbs, designated CN 8, recognized a cell wall component contained in the hemicellulosic fraction. Immunohistochemical analyses showed that the CN 8 epitope was localized to the cell wall of immature tracheary elements and xylem parenchyma cells. In immature tracheary elements, the CN 8 epitope had a polarized localization pattern regardless of whether the cells are formed as parts of vessels in situ or as single tracheary elements in vitro, suggesting that cell polarity autonomously formed on the cell wall may function in tracheary element differentiation.

Gonadotropin-releasing hormone analog therapy failed to improve predicted final height in two children with central precocious puberty and microcephalus

Long-acting gonadotropin-releasing hormone (GnRH) analog treatment for central precocious puberty (CPP) suppresses excessive bone maturation by inhibiting the pituitary-gonadal axis, and usually assures favorable results for growth potential. Recently, we encountered two children with CPP and microcephalus in whom GnRH analog therapy arrested pubertal development, but could not suppress bone age maturation effectively. Eventually, their final height deteriorated rather than improved. The reason why these two cases did not respond to GnRH analog therapy remains unknown. However, microcephalus and minor cerebral anomalies may have some links to deterioration of final height. Our cases suggest that careful evaluation will be required especially for CPP with microcephalus throughout treatment with GnRH analog.

Suppressive effects of dominant negative ras mutant N116Y on transformed phenotypes of human bladder cancer cells

To investigate the suppressive effect of dominant negative H-ras mutant N116Y on transformed phenotypes, we established two N116Y ras mutant stable transfectant clones (C5, C13) of human bladder cancer cell line, UMUC-2. These N116Y ras mutant transfectants, especially the C5 cells, showed a dramatic change of cellular morphology and significantly reduced growth in soft agar compared to their control. Furthermore, phosphorylation of the Jun NH2-terminal kinase (JNK) was significantly decreased in these transfectants compared to the control. These results suggest that the N116Y-induced suppression of transformed phenotypes in UMUC-2 cells is associated with inhibition of JNK phosphorylation.

Germ-line mutation analysis in patients with von Hippel-Lindau disease in Japan: an extended study of 77 families

We have previously reported on the analysis of germ-line mutations in Japanese von Hippel-Lindau disease (VHL) patients and found mutations in 26 families. We have now extended these studies to include an additional 41 VHL families. Germ-line mutation of the VHL gene was screened by DNA-SSCP, direct sequencing, and Southern blot analysis. To summarize all of the data we have studied in this and our previous report, germ-line mutations have been detected in 55 of 77 (73%) (type 1: 41/62 (66%) and type 2: 14/15 (93%)) families. We found similarities in the nature of germ-line mutations including mutational incidence, location, and DNA substitution patterns between Japanese and Western VHL. These similarities may reflect the predominance of endogenous mutational processes. We also found several interesting characteristics in Japanese VHL. Twenty of 41 (49%) intragenic mutations were unique and not reported in the Western VHL. Four mutations (Arg113Stop, Gln132Stop, Leu158Val, and Cys162Tyr) previously characterized as type 1 mutations were identified in the type 2 (with pheochromocytoma) Japanese families. Genotype-phenotype correlation study suggested non-missense mutations predicted to result in the loss of VHL function were associated with the occurrence of renal cell carcinoma, as in sporadic tumors. Our data add to the diversity of VHL germ-line mutations and provide a better understanding of VHL disease in terms of both clinical management and molecular pathogenesis.

[A case of localized fibrous tumor of the pleura after four years follow up and evaluate the doubling time with computed tomography]

Thirty-five-year female had taken video assisted thoraco-surgery (VATS) and resected her localized fibrous tumor of parietal pleura. She suspected chest tumor with annual X-ray survey for lung disease four years ago. She complained of left side back pain recently. Her chest CT revealed that the tumor enlarged than before. She was performed video assisted thoraco-surgery. The tumor was solid hard and connected to the parietal pleura with pedicle, which was resected easily from her pleural cavity. Histrogical examination detected that her tumor was localized fibrous tumor of parietal pleura. CD 34 and Vimentin were positive and cytokeratin was negative in this case. Four year and two examinations of the chest CT later, we could determine the doubling time (800.7 days) of localized fibrous tumor in this case.

Near-normal linear growth in the setting of markedly reduced growth hormone and IGF-1. A case report

A 14.2-year-old prepubertal boy diagnosed with complete-type growth hormone deficiency and tertiary hypothyroidism, keeps growing in the height range between -1 and -2 SD. He has been treated with levothyroxine only. To understand the growth mechanism of this boy, we analyzed the serum growth hormone (GH) with a radioimmunoassay (RIA), serum GH bioactivity with Nb2 and erythroid progenitor cell bioassays, and growth hormone-binding protein (GHBP) with a ligand-mediated immunofunctional assay (LIFA). In addition, IGF-1 and free IGF-1 were analyzed by immunoradiometric assay (IRMA) and insulin-like growth factor-binding protein-3 (IGFBP-3) by Western immunoblot. Peak GH-RIA responses to insulin, arginine and GH-releasing factor, and nocturnal GH secretion, were low (0.5-2.3 ng/ml); bioactive GH was low (0.313 ng/ml), and GHBP was elevated (84 ng/ml). The serum levels of IGF-1 and free IGF-1 were continuously low, 17.1-39.3 and 0.17-0.26 ng/ml, respectively. Moreover, serum IGFBP-3 levels were low (1.68- 1.39 mg/l) and IGFBP-3 protease activity was negative. Prolactin and insulin were in the normal range. The result of the assay for growth-promoting activity showed that the patient's serum stimulated normal erythroid progenitor cells twice as potently as did healthy thin adult control serum. These results suggest that GH and IGF-1 are not indispensable for maintaining physical growth in this boy. Thus, it appears that circulating GH and IGF-1 are not mandatory requirements for maintaining normal physical growth, and other, as yet uncharacterized, pathways or growth factors might be sufficiently compensatory under certain conditions.

Gelsolin gene therapy by retrovirus producer cells for human bladder cancer in nude mice

Gelsolin, a regulator of the actin cytoskeleton, has been shown previously to act as a tumor suppressor in vitro and in vivo when introduced into certain cancer cell lines. To investigate the in vivo efficacy of gene therapy with the gelsolin gene, we inoculated nude mice with human urinary bladder cancer cells (UMUC-2 or DAB-1) and tested the effects of adding either retroviral DNA constructs containing gelsolin cDNA or retrovirus producer cells that produce the same retroviral constructs at high levels. The addition of retroviral gelsolin cDNA constructs did not inhibit tumor growth; however, this form of gene therapy, in which retrovirus producer cells were introduced, resulted in marked and reproducible tumor growth inhibition and prolonged survival time in the majority of animals tested. These findings demonstrate the potential for treating human urinary bladder carcinomas with the gelsolin gene.

Severe impairment of B cell function in lpr/lpr mice expressing transgenic Fas selectively on B cells

Transgenic lpr/lpr mice expressing functional Fas selectively on B cells were produced in an attempt to elucidate the role of Fas on B cells in the regulation of autoantibody production. The homozygous lpr/lpr mice carrying the transgene did not produce anti-double-stranded DNA antibodies throughout their lives, whereas the development of abnormal lpr T cells (double negative, B220(+)) was not suppressed. Further analyses, however, revealed that the expression of the transgenic Fas on B cells of lpr/lpr homozygous mice resulted in severe impairment of the B cell function. The defect was characterized by a decrease in the number of mature peripheral B cells, a reduction in the serum Ig level and the total failure of B cells to mount antibody responses to stimulations of T-dependent as well as T-independent antigens. Such a defect was prominent only when the transgene was expressed on the lpr/lpr homozygous background. On the contrary, B cells of the transgenic lpr/lpr mice were shown to be capable of producing Ig when stimulated with anti-CD40 in the presence of IL-4 and IL-5. Furthermore, lpr/lpr T cells showed enhanced non-specific cytolytic activity. These observations suggested that the observed B cell defect was probably attributable to the destruction of activated B cells expressing transgenic Fas by aggressive lpr/lpr T cells.

[An autopsy case of pulmonary embolism due to renal angiomyolipoma in an elderly woman]

An 86-year-old woman with a 13-year history of hypertension was admitted because of consciousness disturbance, hypotension, tachycardia, and cyanosis at her extremities. Enhanced computed tomography showed a thrombus in the truncus pulmonalis and right pulmonary artery, and also showed a left renal mass and a right renal cyst. Under a diagnosis of pulmonary embolism we started anticoagulant therapy, but the patient died five days after admission. At autopsy, a saddle-like thrombus was found in the truncus pulmonalis and bilateral trunks of pulmonary arteries. Microscopic examination showed smooth muscle cells in the thrombus. We could not find any other thrombus in the inferior vena cava, intrapelvic veins, nor in veins of lower extremities by milking. We also found tumors in both kidneys. Microscopically all tumors were diagnosed as angiomyolipoma. There were many fibrin thrombi in the sinuses of the tumors but there was no evidence of malignancy. We finally diagnosed pulmonary embolism due to renal angiomyolipoma because there was no other thrombus origin and microscopically the same smooth muscle cells were found both in the renal tumor and the pulmonary thrombus. There is only one case report concerning pulmonary embolism due to renal angiomyolipoma which happened during operative treatment. The treatment method of renal angiomyolipoma is determined by tumor size and symptoms, and usually intensive treatment is not performed in cases without symptoms. Our patient had no symptoms until the onset of severe complication of pulmonary embolism, suggesting that radical treatment is necessary for renal angiomyolipoma with a thrombus even when there are no symptoms.

Novel missense mutation (Leu466Arg) of the DAX1 gene in a patient with X-linked congenital adrenal hypoplasia

We identified a DAX1 missense mutation, a substitution of arginine for leucine at codon 466 (Leu466Arg), in an infant with X-linked congenital adrenal hypoplasia (AHC). A heterozygous substitution, Leu466Arg, was also identified in his mother and sister. Since leucine at position 466 is well conserved among other orphan nuclear hormone receptor superfamilies and Leu466Arg was not detected among 50 normal Japanese control individuals, the mutation is most likely responsible for X-linked AHC. It is interesting to note that Leu466Arg among all mutations ever reported is located at the most C-terminal region of the DAX-1 protein. Most mutations identified previously were located in the C-terminal presumptive ligand binding domain. Hence, the C-terminal end of the DAX-1 protein may play an important role in the biological function, such as in normal adrenal embryogenesis.

[Assessment of QOL and survival for patients undergoing radical cystectomy or bladder preservation for invasive bladder cancer]

PURPOSE

In this study, we have retrospectively compared patient backgrounds, prognosis and QOL (quality of life) in patients with invasive bladder cancer treated by radical cystectomy or by bladder preservation.

PATIENTS AND METHODS

This study enrolled recent 30 cases from each institutions, totally 120 cases from four institutions. All patients were diagnosed with invasive bladder cancer in stage T 2 or T 3, N 0, M 0. The patients planned for preserving the bladder were treated with a combination of intra-arterial chemotherapy and radiation as an induction therapy. The questionnaire used to assess QOL was the EORTC QLQ-C 30 (Japanese-language edition).

RESULTS

Radical cystectomy was selected as the initial treatment in 60 cases (the planned radical cystectomy group). Bladder preservation was planned but the presence of residual tumors after induction therapy underwent radical cystectomy in 18 cases (the preservation-radical cystectomy group). Bladder preservation was achieved in 42 cases (the preservation group). In a comparison of background factors, histologically grade 3 tumor and cases with histology other than transitional cell carcinoma, were significantly common in the planned radical cystectomy group. Because this study is not an randomized test, it is difficult to compare the outcomes between the patients treated by radical cystectomy or by bladder preservation. However, it is indicated that the candidates for bladder preservation therapy exist among the patients with T 2 or T 3, N 0, M 0 bladder cancer. Quality of life, as evaluated from global QL and from physical, cognitive, and emotional function, tended to be better in the patients with their bladder, although no difference was noted among the groups with regard to life role or social function. Symptoms such as sleep disturbance and diarrhea were common in the radical cystectomy groups, and financial impact, constipation, appetite loss, and dyspnea also tended to more frequently affect patients in these groups.

CONCLUSION

Our results indicate that bladder preservation treatment using an induction therapy is one of option of the treatment for clinically T 2 or T 3, N 0, M 0 bladder cancer. We need a prospective randomized study with a long-term follow-up to elucidate true candidates for this treatment.