Sensory system-predominant distribution of leukotriene A4 hydrolase and its colocalization with calretinin in the mouse nervous system.

Leukotriene B4 is a potent lipid mediator, which has been identified as a potent proinflammatory and immunomodulatory compound. Although there has been robust evidence indicating that leukotriene B4 is synthesized in the normal brain, detailed distribution and its functions in the nervous system have been unclear. To obtain insight into the possible neural function of leukotriene B4, we examined the immunohistochemical distribution of leukotriene A4 hydrolase, an enzyme catalyzing the final and committed step in leukotriene B4 biosynthesis, in the mouse nervous system. Immunoreactivity for leukotriene A4 hydrolase showed widespread distribution with preference to the sensory-associated structures; i.e. neurons in the olfactory epithelium and vomeronasal organ, olfactory glomeruli, possibly amacrine cells, neurons in the ganglion cell layer and three bands in the inner plexiform layer of the retina, axons in the optic nerve and tract up to the superior colliculus, inner and outer hair cells and the spiral ganglion cells in the cochlea, vestibulocochlear nerve bundle, spinal trigeminal tract, and lamina II of the spinal cord. Double immunofluorescence staining demonstrated that most of the leukotriene A4-hydrolase-immunopositive neurons coexpressed calretinin, a calcium-binding protein in neurons. The ubiquitous distribution of leukotriene A4 hydrolase was in sharp contrast with the distribution of leukotriene C4 synthase [Shimada A, Satoh M, Chiba Y, Saitoh Y, Kawamura N, Keino H, Hosokawa M, Shimizu T (2005) Highly selective localization of leukotriene C4 synthase in hypothalamic and extrahypothalamic vasopressin systems of mouse brain. Neuroscience 131:683-689] which was confined to the hypothalamic and extrahypothalamic vasopressinergic neurons. These results suggest that leukotriene B4 may exert some neuromodulatory function mainly in the sensory nervous system, in concert with calretinin.

Changing incidence of hepatocellular carcinoma in Japan.

A trend in the incidence of hepatocellular carcinoma (HCC) in Japan was studied from the data of the Osaka Cancer Registry (population, 8,512,351 in 1981) for the period of 1963-1983, the Vital Statistics of Japan, Ministry of Health and Welfare, and the Japan Autopsy Registry which contained 594,132 individually filed cases in the 26-year period from 1958 to 1983. Both cancer registry data and autopsy records showed a more than 2-fold increase in HCC incidence, particularly in the last 10 years or so, among males and a less pronounced increase in females. The same trend was borne out by the cancer registries of Nagasaki City and Miyagi Prefecture and the Vital Statistics. When studied with the autopsy data, it was found that the numbers of autopsies for cirrhosis without HCC and autopsies for HCC (with and without cirrhosis) were about the same in 1958-1961 and that currently (1980-1983) the latter is about 2 times the former. As one of the possible causes of increase in HCC incidence other than prolonged survival of patients with cirrhosis, chronic non-A, non-B hepatitis is discussed.

A method of record linkage.

In cancer epidemiology, prospective approaches are very important both in testing etiological hypotheses and in evaluating preventive procedures. Prospective studies, however, are very difficult and expensive, because a large number of people and a long period of observation are necessary for a satisfactory study. As a data source for follow-up studies, population-based cancer registry is very useful. The Osaka Cancer Registry has been in operation since December, 1962. Since 1968 the data processing, including the work of collation, has been semicomputerized. In order to identify cancer patients, we use the following six indices: date of birth, first Chinese character of a person's family name, address a: city, ward, town or village, address b: further details. i.e., street, avenue, section, hamlet etc., site, and sex. When we have data on the collation indices for the subjects to be followed up, we can conduct follow-up studies easily and accurately, using a semicomputerized collation method similar to that in the cancer registration system. Because the master file of the Osaka Cancer Registry contains the data of cancer cases reported and all cancer deaths among the residents of Osaka Prefecture, we can follow up the subjects living in Osaka Prefecture and obtain data about vitually all cancer incidences and deaths among them. In this follow-up method by means of record linkage to the cancer registry, some considerations should be taken into account for the following factors; coverage of cancer data in the Osaka Cancer Registry, reliability of the collation method, and address of the subjects to be followed up. As an example of a study with this method, we present the follow-up study of the screenees of a mass screening program for stomach cancer.

Chromosomal localization of a gene responsible for vestibulocochlear defects of BUS/Idr mice: identification as an allele of waltzer.

Mice of the bustling mutant strain BUS/Idr have vestibulocochlear defects. bus/bus homozygotes, but not heterozygotes, are hyperactive and display an abnormal behavior such as circling, head bobbing and head tilting. To characterize BUS mice further, the auditory brain-stem response of the mutant was examined. In +/bus heterozygotes as well as control animals, the auditory brain-stem response was developmentally first recorded as early as 11 days of age and heterozygous and normal adults showed typical auditory brain-stem responses with five peaks in a threshold of 40-45 dB SPL. In contrast, bus/bus homozygotes showed no auditory brain-stem response at any age in response to stimuli up to 130 dB SPL, indicating that they are deaf throughout life. Linkage analysis revealed that the responsible gene, originally designated as bus, maps on chromosome 10, 1.09+/-0.9 cM distal to D10Mit127 and D10Mit59, and 0.72+/-0.51 cM proximal to three markers, D10Mit48, D10Mit112 and D10Mit258, at a site indistinguishable from that of the Albany waltzer, v(A/b). The results of allelism tests between BUS and Albany waltzer indicated that bus is allelic with v(Alb). From these data, we propose here that the bus mutation could represent another allele of waltzer, now designated v(bus).

A new mouse model with cochleo-saccular type inner ear defects.

We found a new inner ear mutant exhibiting abnormal behavior, such as circling and head shaking, in a breeding stock of SJL/J mice. The traits are inherited in a simple autosomal-recessive fashion. Animals homozygous for the responsible gene, designated cosa, show no startle response to sounds and an inability to swim. In the inner ears of cosa/cosa homozygous, but not +/cosa heterozygous adults, histopathological features of severe damage that are typical for 'cochleo-saccular' or 'spotting' mutants have been demonstrated. We suggest here that the abnormal mice carry a mutation of a gene that is developmentally switched on in the early stages of development and is involved in endolymph homeostasis.

Degenerative hairlets on the vestibular sensory cells in mutant bustling (BUS/Idr) mice.

The bustling mouse (BUS/Idr: bus) is a mutant mouse strain which exhibits deafness, bustling/hyperkinetic behaviour and functional disorders seemingly related to the vestibular system. This phenotype develops in homozygous (bus/bus) mice and has been shown from cross experiments to be genetically induced by a single autosomal recessive gene. We previously detected, with light and electron microscopy, post-natal degeneration of the inner ear sensory cells in homozygotes. In the present study, we examined, by electron microscopy, the development of pathological changes in the sensory epithelia of the macula acustica and crista ampullaris of homozygous mice of various ages, paying special attention to the detailed morphology of the sensory hairlets. The homozygous mice exhibited specific pathological changes: a decrease in the number of hairs; disarrangement of the kinocilium-stereocilia pattern; and, fused and/or very large stereocilia. Homozygotes also frequently exhibited apical cytoplasmic herniation, or bleb of hair cells, as well as a degenerated kinocilium in the sensory epithelium. Heterozygotes showed similar changes, but to a lesser degree and frequency. As for the vestibular organs, similar pathological changes had developed at day, 17 of gestation. These pathological findings and onset suggest that the BUS mouse may be a mutant mouse strain distinct from other reported strains which display similar behaviour, and may be a useful animal model for the study of human degenerative vestibular disorders.

[Role of population-based cancer registry in cancer epidemiology--epidemiological studies in the Cancer Registration Scheme in Osaka, Japan].

A population-based cancer registration scheme started in three areas in Japan in the 1950s solely for studying cancer incidence in their respective areas. Soon thereafter, several prefectural governments started their own schemes as part of their cancer control programs, effectively expanding the aims of cancer registration: to clarify cancer facts, to elevate the medical care for cancer patients, and to plan and evaluate cancer control programs. The Osaka Cancer Registry (OCR) started in 1962, and has been using epidemiological methods as a tool in constructing its registration scheme, as well as analyzing and utilizing registry data. This report deals with the results obtained in the OCR, classifying these results into four activities of epidemiology. 1. Clarifying cancer facts (descriptive epidemiology): The OCR has been observing incidence, medical care for cancer patients, distribution of cases by clinical stage, and the 5-year relative survival rate, and has estimated the prevalence rate, cured-case rate, and future incidence into the 21st century. Population-based data on histology and multiple cancers collected at the OCR have also contributed to the new approaches in cancer epidemiology. 2. Research on risk factors (analytical epidemiology): The OCR developed a computerized record-linkage system in 1970. This not only made registry work more effective and reliable, but many cohort studies were able to be conducted with relatively little effort and highly reliable results. The cancer case file in the OCR has been linked with the newly prepared data file of the study group, and cancer incidence among the study group has been observed. Finally, cancer risks of possible causal factors in that group have been estimated quantitatively. 3. Evaluation of control programs: Secondary prevention programs (early detection) have been conducted in Japan as major cancer control programs, because effective risk factors were not previously defined. OCR data have been used for estimating sensitivity and specificity of screening tests for various cancers, as well as for evaluating the effect of clinical work on improving survival and on decreasing cancer deaths. 4. Planning future cancer control programs: The OCR has reported on the probable rapid increase of cancer incidence in the 21st century, especially of elderly cancer cases, and cancer cases with poor survival. To control these difficult problems, new cancer programs should be urgently designed and implemented. The authors have recommended that programs be prepared by cancer site, and have already presented a detailed program for lung cancer control.

[A retrospective cohort study of workers in small asbestos industries in south Osaka].

A retrospective cohort study was carried out on asbestos workers who had received health examinations in 1972 to 1974 conducted by the Osaka Health Center. The subjects, total of 789 (329 males, 460 females) were followed-up for 10 years (Jan. 1, 1975-Dec. 31, 1984). There were sixty-one deaths in the cohort--4 tuberculosis, 12 malignant neoplasms (4 stomach cancers, 8 respiratory cancers including one case of pleural mesothelioma), 18 circulatory diseases, 24 respiratory diseases, and 3 other causes of death. Standardized mortality ratio (SMR) was calculated age and sex-specific death rates for the general population in Osaka between 1975-79 and 1980-84. SMR for all causes of death, stomach cancer, respiratory cancer, circulatory diseases, and respiratory diseases were 1.15, 3.29, 0.75, 3.88, 0.93 and 8.63 respectively. Respiratory cancer and respiratory diseases showed statistically significant (p less than 0.01) excess death with a mean death age of 59 and 56 years old respectively.

[Time trends in cancer incidence in Osaka].

Changes in environments and life styles in Japan have caused the recent changes in the time trends of cancer incidence for various sites. Using the data from the Osaka Cancer Registry, time trends during 1966-80 were analysed for cancer incidence of the leading 5 sites: stomach, lung, liver, uterus and breast. Age-adjusted incidence rates of cancers of the stomach (both sexes) and uterus (invasive cancer) decreased to 75% and 64% respectively between the two periods of 1966-68 and 1978-80 while cancers of the lung, liver, and breast reached 163%, 140%, and 143 % during the same period. Decrease of stomach cancer incidence was observed in all age-groups under 79, however, not in the 25-44 age-groups among females. Analyzing the histological data in the registry, it was noticed that estimated incidence of the intestinal type of stomach carcinoma had decreased more rapidly than the diffuse type. In the 30-49 age-groups among females, no decrease was observed of the diffuse type of carcinoma. Concerning lung cancer, a marked increase was observed over 60 years of age. The age-specific incidence curves by birth cohort showed no or very small cohort effects for the population born 1920-29. Among males, percentages of adenocarcinoma and undifferentiated carcinoma have increased and that of epidermoid carcinoma decreased. The change was more marked in the age-groups younger than 59. Liver cancer showed the 3rd highest incidence rate among males and 6th among females. A rising trend in recent years was noticeable over 45 years of age among males. For the invasive uterine carcinoma, the incidence rate has been decreasing in all ages. Comparing these figures with those of whites in Connecticut or of Japanese in Hawaii, the former was higher than the latter and the difference was larger in age-groups over 40. The recent age incidence curve of breast cancer in Osaka came to be close to that in Iceland in 1930-49 when the curve had kept a constant level for age-groups after menopause. Birth cohort effect was observed for in these age classes.

[Trends of cancer occurrence and survival in Japan, and in Osaka].

Recent improvements in cancer medical care in Osaka have resulted in the elevation of survival rates of cancer patients, except for the so-called "refractory" cancers. Five-year relative survival rates for reported patients diagnosed in 1981-1983 were higher than 60% for cancers of the breast, uterus and bladder, and around 40% for rectum, colon and stomach cancers. However, cancers of the liver, gallbladder, pancreas, and lung continued to show very low survival rates of less than 10%. In higher age-groups, advanced cases occupied a larger proportion while cases which received curative resection occupied a smaller proportion. Reflecting this, survival rates were lower in age-groups higher than 75, and the reduction of age-differences between younger and older groups was not observed during the decade. Cancer incidence for all sites in Japan was estimated by the Research Group for Population-based Cancer Registries to be 320,000 in 1985. The stomach, colorectal, lung, liver, and breast were the five leading cancer sites. According to the authors' studies, cancer incidence is projected to be 740,000 in Japan in 2015, of which 40% would be patients of "refractory" cancers and 62% would be aged patients in their upper than 70, though these were 19% and 32% in 1985. In order to combat this difficult situation in the near future, the following activities are urgently required: (1) Promotion of primary preventive measures for incurable cancers. (2) Development of specific therapy programs taking into account of QOL for aged patients as well as advanced patients. (3) Promotion of secondary preventive measures for aged people as well as younger people.

[Experimental studies on prevention of liver metastases by continuous intraportal chemotherapy].

Our experiment was designed to elucidate the efficacy of continuous intraportal chemotherapy (CIPC) for the prevention of liver metastases. Catheter was introduced into ileocecal vein of white rabbit for administration of adriamycin (ADM). VX2 cells were inoculated into portal vein to form liver metastases. Three experiments were designed as follows: 1) Immediately after inoculation of tumor cells, ADM was administered continuously for 7 days. 2) Continuous administration of ADM started on the 3rd day after inoculation of tumor cells. 3) Immediately after inoculation of tumor cells, ADM was administered by CIPC or systemically for 7 days. The same number of tumor cells were inoculated into portal vein and no treatment was given in control group. The rabbits were sacrificed on the 14th day. Number and size of liver metastases were calculated. Results were as follows: In 1) and 2), the metastases in CIPC group were significantly decreased in number and size compared with those in control group. In 3), no metastasis was observed in CIPC group, but a third of the rabbits developed metastases in systemic group. These results suggest that CIPC is effective for prevention of liver metastases and its efficacy is greater than for systemic chemotherapy.

[UFT-E granule compliance in postoperative adjuvant chemotherapy].

UFT-E granules were administered as postoperative adjuvant chemotherapy to patients who had undergone surgery for gastric cancer, colorectal cancer or breast cancer. After treatment for one year, the dose conditions were investigated. The subjects were patients under 75 years of age in whom malignant tumors had been confirmed histologically, who had undergone curative resections, had no marked complications, and from whom personal informed consent had been obtained. As a rule, UFT-E granules were administered orally 450 mg (t.i.d.)/day continuously for one year beginning two weeks after surgery. The dose rate was studied from patient records and the tegafur blood concentrations on the 1st, 2nd, 6th, 8th and 12th month. The appearance of complications or clinical lab test abnormalities was also checked. A total of 19 cases were compliant among the 5 gastric cancer, 10 colorectal cancer, and 7 breast cancer patients. The mean administration period was 459 days (29-879 days), and the mean completion rate was 92.5%. The complications in 4 cases (21.1%) were relatively mild. A comparison of the prescribed dosage and patient records revealed a mean dose rate of 86.3%. From these findings, long-term administration of UFT-E granules with mild side effects is considered feasible. However, to achieve high compliance, it is considered necessary to gain a clear picture of dose conditions from patients records and other sources.

[Trends of lung cancer incidence and its prognosis in Osaka, Japan].

Lung cancer incidence figures in Japan were estimated as 30,000 for males and 11,000 for females for 1989 and represented the second and the fifth leading site of cancer, respectively, according to the Research Group for Population-based Cancer Registration in Japan. It is also estimated that lung cancer will steadily increase in the future. In relative frequencies of the major histological types, squamous cell carcinoma showed a decreasing trend, while small as well as large cell carcinomas showed an increasing trend in Osaka. In the distribution of clinical staging, the proportion of localized cases accounted for only 20% of the lung cancers in 1990. Five-year relative survival rates for lung cancer were 11.3% for all patients and 43.0% for localized cases in Osaka in 1984-1986. The rates were reported as 13.5% and 36.6% for total patients and localized cases, respectively, among caucasians from the SEER Program, a NCI project including 10 population-based cancer registries in the US. No noticeable difference was observed between Japan and the US. To control lung cancer in Japan it is considered vitally important and urgent to develop (1) new examination methods for diagnosing lung cancer in the earlier stage, (2) an efficient and effective cessation campaign for cigarettes smoking and (3) non-smoking based education.

[Pharmacokinetic studies of continuous and bolus intraportal 5-fluorouracil infusion].

We studied the pharmacokinetics of continuous and bolus intraportal 5-FU infusion. In continuous intraportal infusion group, 20 mg/kg of 5-FU was infused into ileocecal vein for an hour and the same dose was infused bolusly in bolus intraportal infusion group. Blood samples were collected from portal vein continuously and liver specimens were obtained continuously. The rabbits were sacrificed at 180 minutes from the start of infusion of 5-FU and small intestine was obtained. The results were as follows: A significantly higher concentration of 5-FU in the portal vein was observed in the continuous intraportal infusion group compared with the one-shot infusion group. But the elimination rate of 5-FU was more rapid after cessation of infusion in the continuous infusion group. The rate of FdUMP elimination in the liver tended to be lower in bolus intraportal infusion. The FdUMP concentration in the small intestine was higher in the continuous intraportal infusion group than in the bolus infusion group. In the continuous intraportal infusion group, the FdUMP concentration in the liver was lower than in the small intestine. This depended on the effect of the 5-FU catabolic enzyme, dihydrouracil dehydrogenase, which is contained in the liver in large quantities. The results suggest that in order to increase the FdUMP concentration in the liver with continuous intraportal 5-FU infusion, suppression of the effect of this enzyme is necessary.

[Pharmacokinetic studies on continuous intraportal 5-fluorouracil infusion].

Pharmacokinetics of 5-FU administered by continuous intraportal infusion were studied by infusing 5 mg/kg, 10 mg/kg, 20 mg/kg, and 40 mg/kg of 5-FU, respectively, into the ileocecal vein for an hour. Blood samples were collected from portal vein, femoral vein and liver, and small intestine specimens were obtained at proper intervals. The rabbits were sacrificed at 120 minutes from the start of 5-FU infusion. The results were as follows: Extremely high concentrations of 5-FU in the portal vein, femoral vein and liver tissue were observed in the 5-FU group infused with 40 mg/kg. This phenomenon was suggested to rely on the effect by which the 5-FU catabolic enzyme, dihydrouracil dehydrogenase, was saturated with a large inflow of 5-FU. FdUMP concentration of the liver was lower than that of the small intestine in all groups. These results suggest that a large dose of 5-FU infusion is effective to increase the FdUMP concentration in the liver with continuous intraportal 5-FU infusion.

[Arterial infusion chemotherapy of 5-FU and leucovorin for patients with liver metastases from colorectal cancer].

Fifteen patients with liver metastases from colorectal cancer were treated by arterial infusion of 5-FU and leucovorin. Two regimens were performed. One was weekly bolus infusion of leucovorin following bolus infusion of 5-FU (bolus group), the other was 5 days continuous infusion of 5-FU and leucovorin in 3 weeks (continuous group). One PR was obtained both in the bolus group and in the continuous groups. The objective response rate was 11% in the bolus group and 20% in the continuous group. The one- and 2-year survival rates for these patients were 40% and 0% in the bolus group, and 80% and 60% in the continuous group, respectively. These results suggest that continuous arterial infusion of 5-FU and leucovorin was more effective than individual bolus arterial infusion of leucovorin and 5-FU for patients with liver metastases from colorectal cancer.

[The effect of intraportal chemotherapy in terms of administered dose of 5-FU].

Forty-six patients with colorectal cancer were studied for the effects of intraportal chemotherapy in terms of the administered dose of 5-FU. No liver metastases occurred in patients with a total dose of more than 4 g of 5-FU. The five-year survival rate for patients with a total dose of more than 4 g of 5-FU was 98%, which was better than that for control (72%). In patients administered 500 approximately 600 mg/body/day of 5-FU, the concentration of 5-FU in the peripheral blood was 0.022 approximately 0.027 microgram/ml. Liver dysfunction occurred in 22%, 33%, and 80% of patients administered less than 4 g, 4 approximately 4.9 g, or more than 5 g of 5-FU, respectively, but almost all of them were grade 1. These results suggest that intraportal chemotherapy administered with a total of more than 4 g of 5-FU was effective for prevention of liver metastases after resection of colorectal cancer.

[Pharmacokinetic study in biochemical modulation therapy of UFT with leucovorin tablet].

Preoperative oral treatment with UFT and leucovorin tablet was performed. Pharmacokinetics, degree of degeneration in the tumor tissue and side effects were studied in 34 patients with colorectal cancer preoperatively given 400 mg/day of UFT with 20 mg/day of leucovorin tablet or 400 mg/day of UFT alone. Results were as follows; 1) there was no significant difference between UFTL group and UFT group regarding concentration of FdUMP in the tumor tissue. In UFTL group, concentration of FdUMP was higher in the tumor tissue of moderately differentiated adenocarcinoma than that of well differentiated adenocarcinoma. No significant differences regarding concentration of FdUMP were obtained between diploid and aneuploid groups. 2) TS inhibition rate in the tumor tissue was 66.8% in UFTL group and 53.2% in UFT group, and there was a significant difference between these two groups. TS inhibition rate in the tumor tissue was higher than that in the normal tissue either in UFTL group or UFT group. However, there were no significant differences of TS inhibition rates regarding differentiation of tumor tissue or DNA ploidy pattern. 3) Degree of degeneration of more than Grade 2 was not obtained in any patients of either UFTL or UFT group. 4) There was no change in blood laboratory data between before and after medication. Only one patient complained Grade 1 pruritus in UFTL group. These results suggest that oral biochemical modulation therapy of UFT with leucovorin tablet is effective because of pharmacokinetically high anti-tumor effect and minimal side effects.

[DNA ploidy pattern of flow cytometry as indicator of degrees of malignancy and prognosis in colorectal cancers].

Cellular DNA content of primary colorectal cancers was measured by flow cytometry and investigated on clinico-pathological features to elucidate the relationship between DNA ploidy patterns and outcomes. IN 144 colorectal carcinomas, DNA diploid carcinomas accounted for 23% and DNA aneuploid carcinomas for 77%. NO significant difference was observed between DNA ploidy pattern and tumor differentiation, lymph node metastasis or lympangial invasion. DNA aneuploid tumor had a tendency to invade vein and to lead to hematogenic metastasis. Patients with DNA aneuploid tumor showed a significantly poor disease-free and overall survival rate. Significantly increased incidence of hematogenic recurrence was demonstrated in the DNA aneuploid cases. These results suggest that the DNA ploidy pattern of colorectal cancers may prove to be of prognostic value.