Immunohistochemical localization of a novel acidic calmodulin-binding protein, NAP-22, in the rat brain

NAP-22 is a neuronal tissue-enriched acidic calmodulin-binding protein with a molecular mass of 22,000 and is recovered in the membrane fraction during biochemical fractionation. We observed the distribution pattern of this protein in the rat brain using an immunohistochemical method by light and electron microscopy. NAP-22 immunoreactivity was detected through the whole brain, and the most dense staining was observed in the forebrain including cerebral cortex, hippocampal formation, olfactory bulb, basal ganglia and thalamus. Immunoreactivity was distributed densely at the neuropil, whereas nerve cells and nerve fibres had little or no reaction. In the brain stem, immunonegative large nerve cell bodies were surrounded by immunopositive varicosities. In the cerebellar cortex, mossy fibre terminals and parallel fibres showed immunoreactivity, whereas Purkinje cells did not. Intracellular distribution was observed in the cerebral and cerebellar cortices. NAP-22 immunoreactivity was noted in the axon terminals, dendritic spines and thin nerve fibres. In these structures, reaction products were associated mainly with synaptic vesicles, pre- and postsynaptic membranes and microtubules. This study demonstrates that the immunoreactivity of NAP-22 is distributed widely in the brain, especially in the synapse, and suggests that this protein is involved in synaptic transmission both in the pre- and postsynaptic region.

Free jejunal pouch graft reconstruction after a resection of hypopharyngeal or cervical esophageal cancer

BACKGROUND/AIMS

Pharyngoesophageal reconstruction using the free vascularized jejunal graft sometimes results in dysphagia and this may be caused by anastomotic stenosis at either the distal or proximal anastomotic site, graft contractility and the entrapment of food in the blind loop after an end-to-side pharyngojejunostomy. We therefore applied pouch procedures to the free jejunal graft in order to improve the ability for such patients to consume normal food.

METHODOLOGY

We performed this procedure on 4 patients with pharyngoesophageal cancer located within the cervical regions.

RESULTS

As a result, the following post-operative complications occurred in 1 case each: anastomotic leakage at the pharyngojejunostomy (proximal anastomosis) which healed spontaneously, and anastomotic stenosis in jejunoesophagostomy (distal anastomosis) which improved after performing endoscopic dilatation.

CONCLUSIONS

However, these complications were not thought to be due to the pouch procedures and the passage of food was found to be excellent in all cases at the time of discharge.

Characterization of a novel rat brain glycosylphosphatidylinositol-anchored protein (Kilon), a member of the IgLON cell adhesion molecule family

In the central nervous system, many cell adhesion molecules are known to participate in the establishment and remodeling of the neural circuit. Some of the cell adhesion molecules are known to be anchored to the membrane by the glycosylphosphatidylinositol (GPI) inserted to their C termini, and many GPI-anchored proteins are known to be localized in a Triton-insoluble membrane fraction of low density or so-called "raft." In this study, we surveyed the GPI-anchored proteins in the Triton-insoluble low density fraction from 2-week-old rat brain by solubilization with phosphatidylinositol-specific phospholipase C. By Western blotting and partial peptide sequencing after the deglycosylation with peptide N-glycosidase F, the presence of Thy-1, F3/contactin, and T-cadherin was shown. In addition, one of the major proteins, having an apparent molecular mass of 36 kDa after the peptide N-glycosidase F digestion, was found to be a novel protein. The result of cDNA cloning showed that the protein is an immunoglobulin superfamily member with three C2 domains and has six putative glycosylation sites. Since this protein shows high sequence similarity to IgLON family members including LAMP, OBCAM, neurotrimin, CEPU-1, AvGP50, and GP55, we termed this protein Kilon (a kindred of IgLON). Kilon-specific monoclonal antibodies were produced, and Western blotting analysis showed that expression of Kilon is restricted to brain, and Kilon has an apparent molecular mass of 46 kDa in SDS-polyacrylamide gel electrophoresis in its expressed form. In brain, the expression of Kilon is already detected in E16 stage, and its level gradually increases during development. Kilon immunostaining was observed in the cerebral cortex and hippocampus, in which the strongly stained puncta were observed on dendrites and soma of pyramidal neurons.

Effect of moderate hypothermia on systemic and internal jugular plasma IL-6 levels after traumatic brain injury in humans

Moderate hypothermia may reduce subsequent neuronal damage after traumatic brain injury. Interleukin (IL)-6 may have a role in the pathogenesis of traumatic neuronal damage or repair. Using the enzyme-linked immunological sorbent assay (ELISA), we serially measured IL-6 levels in plasma obtained from the radial artery (systemic) and internal jugular vein (regional) in 13 cerebral trauma patients who underwent hypothermia of 32-33 degrees C ranged from 4-9 days postinjury and 10 head-injured patients who were maintained at normothermic levels (36-37 degrees C). In both patient populations, surface cooling was used since even in the normothermic group, cooling was needed to maintain patient temperature in the normothermic range. All patients were mechanically ventilated after injection of midazolam and vecuronium. The administration of these agents were continued until the end of the study. Hypothermia was typically maintained for four days, however, in some cases based upon CT findings and/or intra-cranial pressure change, the duration was prolonged. No significant differences were found between the two groups in age, gender and Glasgow Coma Scale upon admission. Further, no differences were found in terms of the classification of computed tomography findings or the occurrence of pupillary abnormalities on admission. The patients in this study had not sustained either abdominal or thoracic trauma. Before inducing hypothermia, IL-6 levels in the arterial and internal jugular venous blood exceeded the normal range. Specifically, the internal jugular plasma levels were significantly higher than those in the arterial plasma. While IL-6 levels in the normothermic group did not decrease even at 4 days postinjury, the plasma cytokine levels fell at both sites sharply after moderate hypothermia. The cytokine suppression found in the hypothermic group continued even after rewarming in these patients showing an improved clinical course, but not in those whose condition worsened. In addition to these changes in cytokine levels, the Glasgow Outcome Scale at 6 months postinjury was significantly higher in the hypothermic group than in the normothermia group. Based on the above, this clinical study with its small patient sample size suggests the need for further prospective randomized studies to examine the role of cytokine suppression in the beneficial effects of moderate hypothermia in patients with traumatic brain injury.

The effectiveness of chemotherapy with cisplatin and 5-fluorouracil for recurrent small cell neuroendocrine carcinoma of the rectum: report of a case

We report herein the case of a 46-year-old-man with small cell neuroendocrine carcinoma (NEC) concomitant with large villous adenoma of the rectum, who underwent abdominoperineal resection with regional lymphnode dissection. The resected specimen was histologically found to contain a small lesion of NEC confined to the submucosa in the large adenoma. A computed tomography scan done 4 months postoperatively revealed recurrences in the liver, lymph nodes, and bone. Therefore, two cycles of sequential intravenous combined chemotherapy with standard doses of cisplatin and 5-fluorouracil (5-FU) were administered, after which the size of each tumor decreased remarkably. Nevertheless, the patient died 8 months after the operation. As there was a fair response of this tumor to the combined chemotherapy of cisplatin and 5-FU, this regimen against NEC of the colon and rectum should be given consideration.

Patient-reported quality of life after radical prostatectomy for prostate cancer

BACKGROUND

Increasingly, quality of life (QOL) assessments are receiving greater attention in the management of malignancies, including prostate cancer. We evaluated the impact of radical prostatectomy on patient QOL 12 months or longer after surgery.

PATIENTS AND METHODS

We evaluated the impact of radical prostatectomy on QOL in 60 patients with prostate cancer. The patients comprised two groups: the first group (n = 32) was evaluated 12 months or longer after radical prostatectomy; the second group (n = 28) was evaluated while awaiting radical prostatectomy. General health-related QOL was measured with the European Organization for Research and Treatment of Cancer Prostate Cancer QOL Questionnaire. Sexual function was assessed with the Sapporo Medical University Sexual Function Questionnaire. A newly developed instrument assessing urinary function was prepared only for the postoperative group.

RESULTS

No differences between the two groups were seen in comparisons of general health-related QOL subscales. Men who underwent surgery reported significant deterioration in sexual function (decreased quality of erection, decreased sexual activity and decreased satisfaction with sex life) than those awaiting surgery. Of the 32 postoperative patients, 26 (81%) did not use pads at all, five (16%) used one or fewer pads per day due to occasional spotting and only one patient (3%) used two to four pads per day to deal with urine dripping. Twenty-six postoperative patients (81%) stated that, given the choice, they would undergo radical prostatectomy again.

CONCLUSIONS

General health-related QOL does not appear to be compromised following radical prostatectomy. Patients are willing to accept some morbidity for a perceived survival benefit. Although minimal urinary dysfunction was reported, most patients were dissatisfied with postoperative sexual function. In preoperative counselling, greater emphasis should be placed on the risk of postoperative impotence.

Urinary undiversion for pelvic actinomycosis: a long-term follow up

BACKGROUND

A 43-year-old woman who had been using intrauterine contraceptive devices for the past 10 years underwent an emergency operation for bowel and urinary obstruction.

METHODS/RESULTS

Frozen section analysis showed undifferentiated adenocarcinoma. Incomplete tumorectomy, ileal resection, partial cystectomy, colostomy and bilateral ureterocutaneostomy were palliatively performed. Postoperatively, periodic acid-Schiff and Grocott-Gomori methenamine tests revealed Actinomyces and the final diagnosis was pelvic actinomycosis. Treatment with penicillin G administered intravenously relieved her symptoms and the lesion was dramatically improved. The patient underwent colostomy closure and urinary undiversion.

CONCLUSIONS

Five years after urinary undiversion, the patient's renal function has been maintained and she can void without incontinence and dysuria.

Oxidative stress and haematological changes in immobilized rats

Immobilization stress induces formation of reactive oxygen species (ROS) and leads to the oxidative injury in various tissues. In this study, the effects of immobilization stress on peripheral blood cells distribution, plasma level of thiobarbituric acid reactive substances (TBARS), and activities of antioxidant enzymes in erythrocytes were investigated in male Fischer rats. A significant increase in plasma TBARS was observed during and after the stress. Dramatic increases of neutrophils and monocytes imply that ROS formation resulted from their activation. Furthermore, the antioxidant activities of catalase and superoxide dismutase (SOD) in erythrocytes were dramatically increased during and after the stress, while a large fall in erythrocyte number was observed. These findings suggest that the activation of immune cells can be a source of the immobilization-induced ROS production, and that antioxidant enzymes in erythrocytes play an important role in preventing the ROS-induced injuries.

Quality of life following surgery for vertebral metastases from breast cancer

BACKGROUND AND OBJECTIVES

The quality of life of patients with vertebral metastases from breast cancer treated with surgery was evaluated.

METHODS

Seven such patients underwent surgery for vertebral metastases following chemoendocrine treatment. They presented with pain and some with neurological compromise.

RESULTS

Following posterior stabilization with a segmental instrument, pain was alleviated in all seven women, two showed improvements in neurological compromise, and performance status was improved in five. In no patient was there neurological deterioration secondary to surgical intervention. They were out of bed on the 4th postoperative day and discharged on the 14th day on average.

CONCLUSIONS

The quality of life was improved for these surgically treated patients. We recommend surgical stabilization for selected patients with a vertebral metastasis from breast cancer.

Intra-operative measurement of the tissue blood flow for evaluating blood supply to the gastric tube for esophageal reconstruction

BACKGROUND/AIMS

Anastomotic leakage after esophageal surgery is still the main reason for post-operative morbidity and mortality. We developed a reliable procedure for evaluating blood supply to the gastric tube after esophageal reconstruction.

METHODOLOGY

After construction of the gastric tube, tissue blood flow was measured intra-operatively at the anastomotic sites using laser Doppler flowmetry.

RESULTS

There was a distinct difference in tissue blood flow at the distal portion of the gastric tube. The tissue blood flow at the sites of attempted anastomosis was considerably decreased compared to the value of the gastric body (control site).

CONCLUSIONS

By measuring tissue blood flow at the attempted anastomotic site intra-operatively using laser Doppler flowmetry, a sufficiently nourished gastric tube could be prepared. It was our hypothesis that total elimination of the ischemic portion would make esophagogastric anastomosis safer and more reliable.

Ultrasensitive assay of prostate-specific antigen for early detection of residual cancer after radical prostatectomy

OBJECTIVES

Perhaps the greatest value of PSA determination in the treatment of prostate cancer is in determining persistent disease after a radical prostatectomy. We investigated the ability of an ultrasensitive PSA assay to detect residual prostate cancer in men at risk for recurrence after a radical prostatectomy.

METHODS

Using the Immulite third-generation PSA assay (detection limit, less than 0.003 ng/mL), and the standard IMx PSA assay, we determined PSA levels in 205 serum samples serially obtained from 34 men after a radical prostatectomy. The average days from surgery to serum sampling was 430 (range, 63 to 1296). Patients were classified as having nonaggressive or aggressive cancers, based on clinicopathologic findings. A biochemical relapse was arbitrarily defined.

RESULTS

All 17 patients with nonaggressive cancers had PSA values of less than 0.02 ng/mL throughout the sampling period. Two of these patients (12%) had 2 or more consecutive PSA increases and were considered as a biochemical relapse. In contrast, 14 (82%) of 17 patients with aggressive cancers fit criteria of a biochemical relapse. All of the relapses were identified within 2 years after surgery. The IMx assay detected only 7 biochemical relapses during the same sampling period.

CONCLUSIONS

Using the Immulite PSA assay, relapse detection times may be shortened allowing for most serological recurrences to be detected within 2 years after a radical prostatectomy. Patients with aggressive cancers may require frequent postoperative PSA determinations with a highly sensitive PSA assay which would allow early intervention when treatments for relapse are effective.

Sex hormone-receptor-negative tumors have a higher proliferative activity than sex hormone-receptor-positive tumors in human adenocarcinomas of the gastrointestinal tract

To determine whether a correlation exists between hormone receptors and their proliferative activities, the levels of estrogen receptors (ER) and progesterone receptors (PgR) in surgical specimens from 23 patients with gastric cancer and from 32 patients with colorectal cancer were investigated using an enzyme immunoassay. These values were examined in relation to the parameters of cell kinetics determined by DNA flow cytometry. When the cutoff value was determined as 2.0 fmol/mg of cytosolic protein, ER and PgR were found in 13 (56%) and 6 (26%) of the 23 patients with gastric cancer, respectively, and in 10 (31%) and 10 (31%) of the 32 patients with colorectal cancer, respectively. There was a significant correlation in the expressions of ER between the cancer tissues and normal mucosa (P = 0.040). Although the expressions of ER or PgR were apparently not related to pathological status, better correlations of hormone receptor-negative tumors with increased hyperaneuploid levels were evident. According to a multiple regression analysis, ER levels significantly correlated with changes in the DNA index (P = 0.041) and in the heterogeneity index score (HIS) (P = 0.034). Thus, sex hormone receptors proved to be relevant factors associated with the proliferative activity of adenocarcinoma of the gastrointestinal tract. These findings indicate that the expression of hormone receptors provides pertinent biological information required to determine adequate therapeutic regimens in patients with gastrointestinal cancer.

Peritoneal collagen type IV concentration in adenocarcinoma of the gastrointestinal tract and its relationship to histological differentiation, metastasis, and survival

To determine if peritoneal collagen type IV levels could serve as a parameter for predicting metastasis and the subsequent course of disease, the concentration of collagen IV in the peritoneal fluid of 85 patients with adenocarcinoma of the gastrointestinal tract, including 50 with gastric cancer and 35 with colorectal cancer, was measured radioimmunologically. The peritoneal collagen type IV levels were elevated in 13 (26%) of the patients with gastric cancer, in 8 (23%) of those with colorectal cancer, and in none of the control subjects. The mean concentration of collagen type IV in tumors characterized by peritoneal dissemination was significantly higher than that in those without metastasis; however, there were no significant differences in the collagen type IV levels between tumors with and those without liver metastasis, or between those with and those without lymph node metastasis. There was a significant correlation between the peritoneal collagen type IV level and survival time in patients with clinically evident peritoneal dissemination. A positive correlation was also found between collagen type IV and carcinoembryonic antigen levels. In conclusion, the levels of peritoneal collagen type IV provide evidence of peritoneal dissemination, and can aid in the prediction of life expectancy in patients with adenocarcinomas of the gastrointestinal tract.

Value of the free to total prostate specific antigen ratio and prostate specific antigen density for detecting prostate cancer in Japanese patients

BACKGROUND

This study evaluated the free to total serum prostate specific antigen (f/t PSA) ratio and prostate specific antigen density (PSAD) in detecting prostate cancer in Japanese males with a PSA level between 2.5 and 20.0 ng/mL in a community-based urology practice.

METHODS

Twenty-six patients with clinically localized prostate cancer and 44 patients with histologically-proven benign prostatic hyperplasia (BPH) were studied. The serum levels of free PSA (fPSA) and total (t) PSA were determined using a chemiluminescent enzyme immunoassay. The f/t PSA ratio was calculated by dividing the fPSA value by the total PSA value and was compared with the PSA and PSAD via the receiver operating characteristic (ROC) curves.

RESULTS

Patients with prostate cancer had a significantly lower f/t PSA ratio than patients with BPH. The PSAD was a superiordiagnostic tool over PSA (P< 0.01) when analyzed by ROC curves. The f/t PSA ratio was also superior to PSA, but lacked significance (P=0.12), and similarly, the PSAD was superior, but not significant, to the f/t PSA ratio. Using a cut-off value of 0.19, the PSAD had a sensitivity of 81% and a specificity of 82%. With a cut-off value of 14.0%, the f/t PSA ratio had a sensitivity of 81% and a specificity of 66%.

CONCLUSION

This study showed that PSAD alone improved cancer detection significantly better than PSA. However, it is still unclear whether the f/t PSA ratio is superior to PSA or PSAD in the discrimination between BPH and prostate cancer in Japanese male patients.

Interstitial laser coagulation for management of benign prostatic hyperplasia: a Japanese experience

PURPOSE

The principle of interstitial laser coagulation is to shrink the prostate by generating intraprostatic necrosis without damaging the urethra or causing tissue sloughing. The clinical efficacy and durability of interstitial laser coagulation in the treatment of benign prostatic hyperplasia (BPH) were evaluated.

MATERIALS AND METHODS

From December 1993 to June 1996, 76 patients with symptomatic BPH were treated with interstitial laser coagulation. A neodymium:YAG laser was used in combination with a specially designed interstitial thermotherapy light guide. The tip of the light guide was inserted into each lobe of the prostate transurethrally under direct vision. All evaluations were made at baseline and then 1, 3, 6 and 12 months after therapy. Treatment outcome was evaluated by International Prostate Symptom Score (I-PSS), flow rate and post-void residual urine volume. Disease specific quality of life was assessed via a quality of life assessment score and a BPH impact index. Independent of symptom assessment, a self-reporting questionnaire was prepared at 3 months postoperatively regarding satisfaction with treatment and sexual function.

RESULTS

Among 44 patients followed to 12 months the mean I-PSS significantly decreased from 20.4 at baseline to 7.4, representing 64% improvement (p <0.001). Peak flow rate increased by 50% from a preoperative average of 7.4 to 11.1 ml. per second at 12 months in 42 patients (p <0.001). The post-void residual volume decreased by 57% from 102 to 44 ml. at 12 months in 40 cases (p <0.001). Steady and progressive improvement was observed on quality of life assessment and BPH impact index scores at 3, 6 and 12 months. No patients reported new onset of erectile dysfunction. No serious side effects were observed, except for loss of ejaculation in 3 cases and seminal vesicle abscess in 1. Only 6 patients (8%) required re-treatment for persisting obstructive symptoms during 12 months of followup. A recent change in methods towards more aggressive treatment plausibly influenced the outcomes to require less repeat treatment.

CONCLUSIONS

After the interstitial laser coagulation procedure satisfactory results were obtained and improvement lasted through 12 months. Although the optimal number of fiber placements for each prostate is not known, more aggressive treatment appears to provide better outcomes.

Interstitial laser coagulation for management of benign prostatic hyperplasia: a Japanese experience

PURPOSE

The principle of interstitial laser coagulation is to shrink the prostate by generating intraprostatic necrosis without damaging the urethra or causing tissue sloughing. The clinical efficacy and durability of interstitial laser coagulation in the treatment of benign prostatic hyperplasia (BPH) were evaluated.

MATERIALS AND METHODS

From December 1993 to June 1996, 76 patients with symptomatic BPH were treated with interstitial laser coagulation. A neodymium:YAG laser was used in combination with a specially designed interstitial thermotherapy light guide. The tip of the light guide was inserted into each lobe of the prostate transurethrally under direct vision. All evaluations were made at baseline and then 1, 3, 6 and 12 months after therapy. Treatment outcome was evaluated by International Prostate Symptom Score (I-PSS), flow rate and post-void residual urine volume. Disease specific quality of life was assessed via a quality of life assessment score and a BPH impact index. Independent of symptom assessment, a self-reporting questionnaire was prepared at 3 months postoperatively regarding satisfaction with treatment and sexual function.

RESULTS

Among 44 patients followed to 12 months the mean I-PSS significantly decreased from 20.4 at baseline to 7.4, representing 64% improvement (p <0.001). Peak flow rate increased by 50% from a preoperative average of 7.4 to 11.1 ml. per second at 12 months in 42 patients (p <0.001). The post-void residual volume decreased by 57% from 102 to 44 ml. at 12 months in 40 cases (p <0.001). Steady and progressive improvement was observed on quality of life assessment and BPH impact index scores at 3, 6 and 12 months. No patients reported new onset of erectile dysfunction. No serious side effects were observed, except for loss of ejaculation in 3 cases and seminal vesicle abscess in 1. Only 6 patients (8%) required re-treatment for persisting obstructive symptoms during 12 months of followup. A recent change in methods towards more aggressive treatment plausibly influenced the outcomes to require less repeat treatment.

CONCLUSIONS

After the interstitial laser coagulation procedure satisfactory results were obtained and improvement lasted through 12 months. Although the optimal number of fiber placements for each prostate is not known, more aggressive treatment appears to provide better outcomes.

Free-to-total prostate specific antigen ratio in clinical staging of prostate cancer

The value of the free-to-total serum prostate-specific antigen (f/t PSA) ratio was compared with that of the total prostate specific antigen (tPSA) value for the prediction of clinical stage in patients with prostate cancer. The f/t PSA ratio was obtained from the frozen sera of 56 untreated patients with histologically proven BPH and 78 patients with prostate cancer. The clinical stage was organ-confined in 36, locally advanced in 20 and metastatic in 22 patients. Serum levels of free PSA (fPSA) and tPSA were determined using a chemiluminescent enzyme immunoassay. The f/t PSA ratio was calculated by dividing the fPSA value by the tPSA value and was compared with tPSA and fPSA in the correlation with clinical stage via the Spearman rank correlation test. Patients with prostate cancer had a significantly lower f/t PSA ratio than patients with BPH. The f/t PSA ratio did not differ between patients with clinically localized and metastatic cancer. tPSA and fPSA reflected the clinical stage and the extent of bone metastasis more accurately than the f/t PSA ratio. The extent of bone metastasis had no effect on the PSA ratio. The f/t PSA ratio had no additional value in clinical staging compared to tPSA. Our study suggests that the f/t PSA ratio does not reflect tumor load.

Abdominal surgery for patients on maintenance hemodialysis

Despite the growing number of major surgical procedures being performed for patients on maintenance hemodialysis, few reports focus on the management and outcome of such patients, especially those undergoing major abdominal surgery. We conducted a retrospective review of 30 patients on maintenance hemodialysis who underwent abdominal surgery, 20 of whom underwent an elective operation and 10, an emergency operation. The indications of elective surgery included gastrointestinal cancer, biliary tract disease, and abdominal aortic aneurysm, while those for emergency surgery mainly involved gastrointestinal perforation or bleeding. There were no statistically significant differences between the elective group and the emergency group regarding either the mean time on hemodialysis or the preoperative clinical data. The morbidity and mortality rates were 15% and 10%, respectively, for the patients who underwent elective surgery and 50% and 70%, respectively, for those who underwent emergency surgery (P < 0.01 and P < 0.05, respectively). Those patients with more than a 2-year history of hemodialysis had a significantly higher mortality rate following abdominal surgery than those with less than a 2-year history (P < 0.01). Thus, the morbidity and mortality rates of patients on maintenance hemodialysis who require major abdominal surgery are significantly high, which reinforces the need to further improve the intensive perioperative management of such patients.

[Serum carcinoembryonic antigen doubling time in patients with recurrent gastrointestinal carcinoma and its relationship to tumor biology and life expectancy]

BACKGROUND

The present study was done to determine if carcinoembryonic antigen (CEA) concentration doubling time can predict the course of disease in patients with adenocarcinoma of the gastrointestinal tract and characterize tumor biology.

METHODS

CEA doubling times were determined from semilogarithmic plots of CEA concentration time courses in 20 patients with recurrent gastric cancer and 17 with recurrent colorectal cancer.

RESULTS

Gastric and colorectal carcinomas showed mean CEA doubling times of 229 days and 85 days, respectively. There were no significant differences with regard to patient age, tumor size, gross appearance and histological differentiation. However, women had shorter CEA doubling times than did men. Flow cytometric analysis showed that tumors with a higher proportion of cells in S-phase (> or = 15%) had significantly shorter CEA doubling times than those with a lower S-phase fraction (< 15%). There was a significant correlation between the CEA doubling time and the length of survival after the initial CEA concentration increase in patients with recurrent gastric and colorectal carcinomas.

CONCLUSIONS

CEA doubling time predicts life expectancy in patients with adenocarcinoma of the gastrointestinal tract. Differences in survival time are closely associated with variations in the biological aggressiveness of individual tumors.

Production of immunoreactive 2',5'-oligoadenylate synthetase in p48-deficient mice

2',5'-Oligoadenylate synthetase (2'5'OAS), an enzyme induced by interferon (IFN), is physiologically produced in IFN-untreated normal healthy mice. The enzyme is localized mainly in the epithelium of the digestive tract, reproductive organs, and the choroid plexus in the brain. 2'5'OAS is also detected in oocytes in the ovary and in neurons and glial cells of both the telencephalon and cerebellum. Here, we examined the role of p48 (ISGF3gamma), a component of IFN-stimulated gene factor 3 (ISGF3), in the physiologic production of 2'5'OAS using p48-deficient mice generated by gene targeting. In the p48-deficient mice, the physiologic production of 2'5'OAS localized in the following cells was severely impaired: hepatocytes, Kupffer cells, splenocytes, epithelium of the large intestine, oviduct, and uterus, and neurons and glial cells in both the telencephalon and cerebellum. The results show that 2'5'OAS in these cells is induced physiologically through a pathway including p48. However, the production of 2'5'OAS in oocytes was not affected in the p48-deficient mice, indicating that oocyte 2'5'OAS is produced through a p48-independent pathway. A possible function of the GAS sequence found in the promoter region of the 2'5'OAS gene to which Stat6 may bind also is discussed.

The target cells of injected type I interferons in mouse liver

Type I interferons (IFNs) have been used for the treatment of viral hepatitis, but it is unclear which cells in the liver are affected by injected IFN. The effects of IFN have been studied by the production of 2',5'-oligoadenylate synthetase (2'5'OAS), an IFN-inducible enzyme. Here, we studied the distribution of 2'5'OAS in mouse liver after injection of natural mouse IFN-alpha/beta by Western blotting and immunohistochemistry using a monoclonal antibody specific to mouse 42-kDa 2'5'OAS. Injection of IFN-alpha/beta increased the levels of liver 2'5'OAS and enhanced the intensities of immunohistochemical staining for this enzyme in both hepatocytes and Kupffer cells. In IFN-untreated normal mice, hepatocytes were lightly stained, but some of the Kupffer cells showed rather strong staining. The 2'5'OAS-positive Kupffer cells comprised approximately 60% of those in normal liver, whereas this increased to approximately 90% following IFN-alpha/beta injection. Thus, hepatocytes and Kupffer cells were the targets of injected IFN.

Two types of chicken 2',5'-oligoadenylate synthetase mRNA derived from alleles at a single locus

We have isolated two types of chicken 2',5'-oligoadenylate synthetase cDNAs, A and B, which encode predicted proteins of 508 amino acids (58316 Da) and 476 amino acids (54336 Da), respectively. The region of A-protein comprising 33 amino acid residues from 385Ala to 417Cys is substituted by a single amino acid 385Tyr in B-protein. The homology between chicken and mammalian 2',5'-oligoadenylate synthetases is 49.5% over the amino-terminal 337 residues. Proteins expressed from A- and B-cDNAs in E. coli cells were both active in synthesizing 2',5'-oligoadenylate. However, the activity of B-protein was 10-15% of that of A-protein. Southern blotting hybridization indicated that the chicken synthetases are encoded by a single gene. RT-PCR and PCR analyses of RNA and DNA of chicken erythrocytes together with the sequence data of the PCR products showed that A- and B-mRNAs are derived from alleles at a single locus encoding chicken 2',5'-oligoadenylate synthetase, designated as OAS * A and OAS * B. Chickens carrying OAS * A/B produce two types of synthetase with molecular masses of 58 and 54 kDa, and those carrying OAS * A/A produce only a single type of 58 kDa.