Periostin in Cancer-Associated Fibroblasts Promotes Esophageal Squamous Cell Carcinoma Progression by Enhancing Cancer and Stromal Cell Migration

Cancer-associated fibroblasts (CAFs) in the tumor microenvironment are involved in the progression of various cancers, including esophageal squamous cell carcinoma (ESCC). CAF-like cells were generated through direct co-culture of human bone marrow-derived mesenchymal stem cells, one of CAF origins, with ESCC cells. Periostin (POSTN) was found to be highly expressed in CAF-like cells. After direct co-culture, ESCC cells showed increased malignant phenotypes, such as survival, growth, and migration, as well as increased phosphorylation of Akt and extracellular signal-regulated kinase (Erk). Recombinant human POSTN activated Akt and Erk signaling pathways in ESCC cells, enhancing survival and migration. The suppression of POSTN in CAF-like cells by siRNA during direct co-culture also suppressed enhanced survival and migration in ESCC cells. In ESCC cells, knockdown of POSTN receptor integrin β4 inhibited Akt and Erk phosphorylation, and survival and migration increased by POSTN. POSTN also enhanced mesenchymal stem cell and macrophage migration and endowed macrophages with tumor-associated macrophage-like properties. Immunohistochemistry showed that high POSTN expression in the cancer stroma was significantly associated with tumor invasion depth, lymphatic and blood vessel invasion, higher pathologic stage, CAF marker expression, and infiltrating tumor-associated macrophage numbers. Moreover, patients with ESCC with high POSTN expression exhibited poor postoperative outcomes. Thus, CAF-secreted POSTN contributed to tumor microenvironment development. These results indicate that POSTN may be a novel therapeutic target for ESCC.

Significance of Preoperative Tooth Loss in Patients Who Underwent Gastrectomy for Gastric Cancer

Background/Aim

The relationship between gastric cancer and oral health has been reported in several studies. This study aimed to determine the relationship between the postoperative prognosis of gastric cancer and oral health using preoperative tooth loss as a simple index.

Patients and Methods

We conducted a single-center retrospective cohort study. Patients were divided into two groups according to the number of tooth losses. The survival curve was constructed using the Kaplan-Meier method. We also performed univariate and multivariate analyses of overall survival based on Cox proportional hazard regression to determine prognostic factors.

Results

A total of 191 patients were divided into two groups: those with seven or more tooth losses and those with less than seven tooth losses. The three-year overall survival rate was 71.5% in the group with seven or more tooth losses and 87.0% in the group with less than seven tooth losses. The group with seven or more tooth losses had a significantly lower overall survival rate compared to the group with less than seven tooth losses (p=0.0014). However, in multivariate analysis, tooth loss was not identified as an independent prognostic factor whereas age, clinical T stage, CEA level, and serum albumin level were independent poor prognostic factors.

Conclusion

Preoperative tooth loss was not a prognostic factor for gastric cancer after gastrectomy, but tooth loss may be a simple and useful method for evaluating frailty in patients.

IFI16 Induced by Direct Interaction between Esophageal Squamous Cell Carcinomas and Macrophages Promotes Tumor Progression via Secretion of IL-1α

Tumor-associated macrophages (TAMs), one of the major components of the tumor microenvironment, contribute to the progression of esophageal squamous cell carcinoma (ESCC). We previously established a direct co-culture system of human ESCC cells and macrophages and reported the promotion of malignant phenotypes, such as survival, growth, and migration, in ESCC cells. These findings suggested that direct interactions between cancer cells and macrophages contribute to the malignancy of ESCC, but its underlying mechanisms remain unclear. In this study, we compared the expression levels of the interferon-induced genes between mono- and co-cultured ESCC cells using a cDNA microarray and found that interferon-inducible protein 16 (IFI16) was most significantly upregulated in co-cultured ESCC cells. IFI16 knockdown suppressed malignant phenotypes and also decreased the secretion of interleukin-1α (IL-1α) from ESCC cells. Additionally, recombinant IL-1α enhanced malignant phenotypes of ESCC cells through the Erk and NF-κB signaling. Immunohistochemistry revealed that high IFI16 expression in human ESCC tissues tended to be associated with disease-free survival and was significantly associated with tumor depth, lymph node metastasis, and macrophage infiltration. The results of this study reveal that IFI16 is involved in ESCC progression via IL-1α and imply the potential of IFI16 as a novel prognostic factor for ESCC.

Biological and clinical significance of the YKL-40/osteopontin-integrin β4-p70S6K axis induced by macrophages in early oesophageal squamous cell carcinoma

M2 macrophages contribute to the progression of oesophageal squamous cell carcinoma (ESCC); however, the roles of M2 macrophages in early ESCC remain unclear. To clarify the biological mechanisms underlying the interaction between M2 macrophages and oesophageal epithelial cells in early-stage ESCC, in vitro co-culture assays between the immortalised oesophageal epithelial cell line Het-1A and cytokine-defined M2 macrophages were established. Co-culture with M2 macrophages promoted the proliferation and migration of Het-1A cells via the mTOR-p70S6K signalling pathway activated by YKL-40, also known as chitinase 3-like 1, and osteopontin (OPN) that were hypersecreted in the co-culture supernatants. YKL-40 and OPN promoted the above phenotypes of Het-1A by making a complex with integrin β4 (β4). Furthermore, YKL-40 and OPN promoted M2 polarisation, proliferation, and migration of macrophages. To validate the pathological and clinical significances of in vitro experimental results, immunohistochemistry of human early ESCC tissues obtained by endoscopic submucosal dissection (ESD) was performed, confirming the activation of the YKL-40/OPN-β4-p70S6K axis in the tumour area. Moreover, epithelial expression of β4 and the number of epithelial and stromal infiltrating YKL-40- and OPN-positive cells correlated with the Lugol-voiding lesions (LVLs), a well-known predictor of the incidence of metachronous ESCC. Furthermore, the combination of high expression of β4 and LVLs or high numbers of epithelial and stromal infiltrating YKL-40- and OPN-positive immune cells could more clearly detect the incidence of metachronous ESCC than each of the parameters alone. Our results demonstrated that the YKL-40/OPN-β4-p70S6K axis played important roles in early-stage ESCC, and the high expression levels of β4 and high numbers of infiltrating YKL-40- and OPN-positive immune cells could be useful predictive parameters for the incidence of metachronous ESCC after ESD. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Matrix Metalloproteinase 9 Induced in Esophageal Squamous Cell Carcinoma Cells via Close Contact with Tumor-Associated Macrophages Contributes to Cancer Progression and Poor Prognosis

Tumor-associated macrophages (TAMs) contribute to disease progression in various cancers, including esophageal squamous cell carcinoma (ESCC). We have previously used an indirect co-culture system between ESCC cell lines and macrophages to analyze their interactions. Recently, we established a direct co-culture system to closely simulate actual ESCC cell-TAM contact. We found that matrix metalloproteinase 9 (MMP9) was induced in ESCC cells by direct co-culture with TAMs, not by indirect co-culture. MMP9 was associated with ESCC cell migration and invasion, and its expression was controlled by the Stat3 signaling pathway in vitro. Immunohistochemical analyses revealed that MMP9 expression in cancer cells at the invasive front ("cancer cell MMP9") was related to high infiltration of CD204 positive M2-like TAMs (p < 0.001) and was associated with worse overall and disease-free survival of patients (p = 0.036 and p = 0.038, respectively). Furthermore, cancer cell MMP9 was an independent prognostic factor for disease-free survival. Notably, MMP9 expression in cancer stroma was not associated with any clinicopathological factors or patient prognoses. Our results suggest that close interaction with TAMs infiltrating in cancer stroma or cancer nests induces MMP9 expression in ESCC cells, equipping them with more malignant features.

A case of pulmonary leiomyosarcoma achieving long-term survival after multiple metastasectomies

A 58-year-old man who underwent lower lobectomy of the right lung for primary pulmonary leiomyosarcoma (PPL) 4 years ago presented with epigastric pain and was diagnosed with small bowel intussusception caused by an intestinal mass. Partial resection of the small intestine was performed, and pathological examination revealed metastatic leiomyosarcoma. Masses in the left adrenal gland, subcutaneous tissue of the left upper arm, right pleura, jejunum, right trapezius muscle, and right adrenal gland were subsequently detected in the following 4 years. Resection was performed for each tumor, which was histologically confirmed as metastatic leiomyosarcoma. However, 1 month after the last surgery, multiple systemic metastases were found, thus, he is currently undergoing chemotherapy. The patient has been alive for 8 years and 4 months after the first operation for PPL. PPL is an extremely rare disease with no established treatment strategy for recurrences. Aggressive metastasectomy may be beneficial in selected cases.

Early Enteral Feeding of Daikenchuto Stimulates Early Bowel Movement With Increased Portal Venous Blood Flow After Living Donor Liver Transplantation

Daikenchuto (DKT), a Japanese Kampo medicine, had been reported to increase small intestinal blood flow after liver resection. The aim of this study was to evaluate the effects of early enteral feeding of DKT on portal venous flow and early bowel movement after living donor liver transplantation (LDLT) in an attempt to clarify whether these effects on bowel motility can prevent bacterial and/or fungal translocation.

MATERIALS AND METHODS

Our prospective study included the consecutive 16 LDLT recipients at Mie University Hospital between June 2006 and September 2009. Sixteen patients were divided into the 2 groups according to enteral feeding starting postoperative day (POD) 1: 8 patients in DKT (15 g/d) administration (DKT group, for 1 week) and 8 patients in tepid water administration (non-DKT group, for 1 week). Portal venous flow, portal venous pressure, presence of fungal infection (serum level of β-D-glucan and fungal polymerase chain reaction assay), time to first food intake, and time to first defecation were serially examined.

RESULTS

Portal venous flow (mean [SD] velocity) was significantly increased in DKT group compared with non-DKT group: 47.5 (12.9) vs 31.8 (15.4) (P = .04) on POD 1, 46.8 (11.5) vs 28.8 (12.5) (P = .03) on POD 3, and 42.3 (17.2) vs 25.2 (9.0) (P = .05) on POD 5. However, mean (SD) portal venous pressures did not significantly change between the 2 groups. Between the 2 groups (DKT vs non-DKT), the day of first oral intake was not significantly different: 6.9 (2.5) vs 11.3 (8.7) (P = .061), but the mean (SD) day of first defecation was significantly shorter in the DKT group: 3.9 (1.1) vs 5.5 (2.6) (P = .02). Although fungal polymerase chain reaction assay was not significantly different between the 2 groups (4 vs 4 positive cases), the mean (SD) serum levels of β-D-glucan were significantly lower in the DKT group than in the non-DKT group: 9.0 (7.4) vs 18.4 (15.9) pg/mL (P = .04).

CONCLUSION

Early enteral feeding of DKT after LDLT increased portal vein blood flow without increasing portal vein pressure and stimulated early bowel movement, which in turn might prevent fungal translocation.

Isolated Biliary Fistula After Donor Right Hepatectomy and Its Novel Interventional Treatment: Isolated Liver-Punctured Drainage

Isolated biliary leakage is difficult to manage, and afflicted patients often develop refractory fistula. The present case was a 43-year-old male donor whose wife developed acute fulminant liver failure. Computed tomography (CT) volumetry showed that the estimated remnant liver volume was only 394 mL (31%) if his right lobe would be harvested. Since remnant liver volume was marginal, our proposed cut line for the right hepatectomy was set in order to preserve branches of the middle hepatic vein draining segments 4b+8 and 5. Right hepatectomy was performed, but on postoperative day 14, the donor developed fever and right back pain, and enhanced CT showed a 6 cm intra-abdominal abscess at the site of cutting, and we diagnosed it as an isolated biliary fistula since the isolated segment 5/8 was receiving arterial blood supply and exhibiting regrowth. A transabdominal abscess drainage was performed, after which the patient lost 30 to 50 mL of bile juice per day in drainage until 2 months after the drainage procedure. Ethanol injection, acetic acid injection, and transarterial or portal embolization for the isolated liver were proposed, but these all were impossible to carry out because there were no accessible routes. Thus, re-abscess drainage with a 7-French drainage catheter was performed through the isolated liver on postoperative day 53, and the isolated functional liver was punctured to induce liver atrophy. After this drainage, the isolated liver started to shrink and bile output had been stopped. In conclusion, our punctured-liver drainage could be effective for the treatment of isolated biliary fistula, allowing physicians to avoid an invasive additional liver resection or other invasive percutaneous approach using chemical reagents.

Intravenous Administration of Tacrolimus Stabilizes Control of Blood Concentration Regardless of CYP3A5 Polymorphism in Living Donor Liver Transplantation: Comparison of Intravenous Infusion and Oral Administration in Early Postoperative Period

BACKGROUND

We compared achievement rate of sufficient tacrolimus blood concentration in the early postoperative period and incidence of acute cellular rejection within 1 month after living donor liver transplantation (LDLT) between tacrolimus intravenous (IV) and oral administration groups.

METHODS

From October 2005 to November 2016, 61 LDLT patients administered tacrolimus, who could be genotyped for CYP3A5*3 and *1, were chosen from the electronic record database. The patients were then divided into the 2 groups (an IV group [n = 38] and an oral group [n = 23]). We defined patients with 1*1 or *1*3 as expressors and those with *3*3 as nonexpressors. Sufficient trough level tacrolimus blood concentration on postoperative day (POD) 3 was defined as 10-20 ng/mL.

RESULTS

Comparable concentrations were seen between the 2 groups, with mean blood concentration 13.7 ± 8.5 ng/mL in the oral group and 15.2 ± 4.3 ng/mL in the IV group. Achievement rate of sufficient tacrolimus concentration on POD 3 was significantly higher in the IV group than in oral group: 97% (37 of 38) vs 65% (15 of 23), respectively (P = .001). When we focused on achievement rate in the oral group according to CYP3A5 polymorphism, the frequency of expressors (17%) was significantly lower than that of nonexpressors (82%) (P = .016). However, in the IV group this negative influence was totally eliminated, resulting in high achievement rates regardless of CYP3A5 polymorphism. In terms of incidence of acute cellular rejection, there was no significant difference between the 2 groups (IV 32% vs oral 17%, P = .250).

CONCLUSION

IV administration of tacrolimus allowed us to obtain more stable control of blood concentration regardless of CYP3A5 genotype.

Pretransplant Serum Hyaluronic Acid Can Be a Biomarker as a Prognostic Predictor in Adult-to-Adult Living Donor Liver Transplantation

OBJECTIVE

The goal of this study was to evaluate whether pretransplant serum hyaluronic acid (HA) levels can predict outcomes after adult-to-adult living donor liver transplantation (LDLT).

METHODS

In study I, 21 patients who underwent LDLT (March 2002-February 2004) were divided into 2 groups: the H-I group (HA ≥500 ng/mL; n = 12) and the L-I group (HA <500 ng/mL; n = 9). The influence of pretransplantation HA levels on short-term surgical outcome was investigated. In study II, 77 LDLT patients (May 2004-December 2014) were also divided into 2 groups: the H-II group (HA ≥500 ng/mL; n = 40) and the L-II group (HA <500 ng/mL; n = 37). We compared long-term survival and investigated prognostic factors.

RESULTS

In study I, HA levels significantly decreased after LDLT, and those in the H-I group were significantly higher compared with the L-I group at 1, 3, 5, and 7 days after LDLT. There were significant differences in postoperative peak total bilirubin levels (H-I vs L-I, 17.2 vs 6.2 mg/dL; P = .013), peak ascitic fluid volume (1327 vs 697 mL/d; P = .005), and the hepatocyte growth factor levels at 3 days after LDLT (1879 vs 1092 pg/mL; P = .03). In study II, the 1- and 5-year survival rates were significantly lower in the H-II group than in the L-II group (H-II vs L-II, 65.0% and 48.5% vs 86.5% and 80.8%; P = .004). In multivariate analysis, significant prognostic factors were preoperative HA ≥500 ng/mL (P = .004) and graft to recipient body weight ratio <0.8 (P = .042).

CONCLUSIONS

Preoperative HA level can be a prognostic risk factor. Patients with high HA levels are vulnerable and should be carefully managed after LDLT.

Discontinuation of Hepatitis B Immunoglobulin by Long-term Hepatitis B Vaccine Inoculation in Preventing Hepatitis B Recurrence After Liver Transplantation

INTRODUCTION

For the patients undergoing liver transplantation for hepatitis B virus (HBV)-related diseases, hepatitis B immunoglobulin (HBIG) should be administered to prevent reinfection. Because HBIG is highly expensive and a blood product, an alternative strategy using HBV vaccination has been made in an attempt to discontinue use of HBIG. The aim of this study was to evaluate the impact of long-term HBV vaccination for discontinuation of HBIG, paying attention to the status of active immunization using T-cell proliferation assay.

PATIENTS AND METHODS

Among the 144 recipients who underwent liver transplantation in our hospital, 16 had HBV-related liver diseases; the 14 patients who had received vaccination were subjects in our study. To evaluate the status of active immunization, T-cell proliferation was examined by counting the number of T cells after adding HBV vaccine to the culture supernatant of T cells, and tumor necrosis factor α and interferon γ were measured in the culture supernatant.

RESULTS

The ratio of male/female was 13/1 (median age: 55 years; range: 37 years to 67 years). The median follow-up time was 102 months (range: approximately 14 months to 148 months). All 14 patients were free of HBV recurrence. HBIG-free status could be achieved in 9 patients (64.3%) during the treatment period for more than 50 months after beginning of HBV vaccination, of whom 5 (35.7%) became HBV vaccine-free. T-cell proliferation was confirmed by fact that the stimulation index ranged from 2.34 to 5.2 in the patients who were HBIG-free.

CONCLUSION

Long-term HBV vaccination after LT is a useful and effective treatment in preventing HBV recurrence, allowing the discontinuation of HBIG treatment.

D-MELD, the Product of Donor Age and Preoperative MELD, Predicts Surgical Outcomes After Living Donor Liver Transplantation, Especially in the Recipients With HCV-positive and Smaller Grafts

BACKGROUND

Appropriate donor-recipient match has not been explored well in living-donor liver transplantation (LDLT) unlike deceased-donor liver transplantation. In this study, we evaluate the donor-recipient match using D-MELD (donor age × recipient Modified for End-stage Liver Disease [MELD] score) as a predictor of surgical outcomes in LDLT, paying attention to graft size and hepatitis C virus (HCV) status.

PATIENT AND METHODS

The 120 consecutive recipients who received adult-to-adult LDLT from March 2002 to December 2014 were divided into the two groups according to D-MELD score: D-MELD <1000 (low-D-MELD: n = 101) and D-MELD ≥1000 (high-D-MELD: n = 19).

RESULTS

The 90-day mortality rate was significantly higher in the high-DM group than in low-DM group: 36.8% versus 14.9% (P = .046). In the HCV-positive recipients, the 90-day mortality rate was significantly higher in high-DM group (n = 6) than in low-DM group (n = 37): 66.7% versus 13.5% (P = .012), and the 3-year survival rate was significantly lower in high-DM group than in the low-DM group: 33.3% versus 56.8% (P = .01). In the recipients with left graft, the 90-day mortality rate was significantly higher in the high-DM group (n = 8) than in the low-DM group (n = 41): 50% versus 14.6% (P = .044), and total bilirubin level on postoperative day 14 was significantly higher in the high-DM group than in the low-DM group: 17.4 mg/dL versus 9.2 mg/dL (P = .018).

CONCLUSIONS

It was clarified that D-MELD could predict early and long-term surgical outcomes in the recipients who were HCV-positive and who had smaller grafts.

Influence of Angiotensin-converting Enzyme Genetic Polymorphism on Late Renal Dysfunction After Adult-to-adult Living-donor Liver Transplantation

BACKGROUND

Late renal dysfunction (LRD) is known to be one of the most important complications to affect long-term outcome after living-donor liver transplantation (LDLT). The relationship between angiotensin-converting enzyme insertion (I)/deletion (D) gene polymorphism and renal function after LDLT are still unknown. The aim of this study was to elucidate the risk factors for LRD after LDLT, focusing on ACE gene polymorphism.

MATERIALS AND METHODS

Among the 94 recipients who underwent adult-to-adult LDLT between March 2002 and September 2009, the total number of subjects who survived more than 1 year after LDLT and in whom angiotensin-converting enzyme genotype could be measured was 64. LRD was defined as estimated glomerular filtration rate level less than 60 mL/min/1.73 m(2) at any point after 1 year from undergoing LDLT.

RESULTS

LRD was found in 24 patients (37.5%). The incidence of LRD was significantly higher in D/D type than in I/I or I/D type: 85.7% (6/7) vs. 42.1% (8/19), 35.7% (10/38) (P = .010). Preoperative estimated glomerular filtration rate was significantly lower in D/D type than in I/I, I/D types, and postoperatively they were significantly lower in D/D type at 2, 3, and 4 years after LDLT. By multivariate analysis, age and hypertension were the independent risk factors for LRD. The 10-year survival rate was much lower in the recipients with LRD than in those without LRD at 66.7% versus 87.5%, respectively (P = .053).

CONCLUSION

In conclusion, age and hypertension were determined as significant independent risk factors for LRD after adult-to-adult LDLT, and the recipients with D/D genotype should be strictly cared for the development of LRD.

Biliary complications in 108 consecutive recipients with duct-to-duct biliary reconstruction in living-donor liver transplantation

BACKGROUND

Biliary complications remain the leading cause of postoperative complications after living-donor liver transplantation (LDLT) in patients undergoing duct-to-duct choledochocholedochostomy. The aim of this study was to analyze the causes of these complications.

METHODS

One hundred eight patients who underwent LDLT with duct-to-duct biliary reconstruction at Mie University Hospital were enrolled in this study. The mean follow-up time was 58.4 months (range, 3-132). The most recent 18 donors underwent indocyanine green (ICG) fluorescence cholangiography for donor hepatectomy. The development of biliary complications was retrospectively analyzed. Biliary complications were defined as needing endoscopic or radiologic treatment.

RESULTS

Biliary leakages and strictures occurred in 6 (5.6%) and 15 (13.9%) of the recipients, respectively, and 3 donors (2.7%) experienced biliary leakage. However, since the introduction of ICG fluorescence cholangiography, we have not encountered any biliary complications in either donors or recipients. Biliary leakage was an independent risk factor for the development of biliary stricture (P = .013). Twelve (80%) of the 15 recipients with biliary stricture had successful nonoperative endoscopic or radiologic management, and 3 patients underwent surgical repair with hepaticojejunosotomy.

CONCLUSIONS

Biliary leakage was an independent factor for biliary stricture. ICG fluorescence cholangiography might be helpful to reduce biliary complications after LDLT in both donors and recipients.

Inhibition of the light-independent synthesis of chlorophyll in pine cotyledons at low temperature

Cotyledons of Japanese black pine (Pinus thunbergii) were yellow when they developed in darkness at 8 degrees C since the light-independent synthesis of chlorophyll was almost completely inhibited in these cotyledons. The level of chlorophyll in dark-grown cotyledons was less than one-twentieth of that in light-grown cotyledons at the same temperature. In the yellow cotyledons, levels of transcripts of cab, rbcS, rbcL and psbA genes were quite high. The large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase were also detected at relatively high levels in yellow cotyledons. However, the accumulation of the two apoproteins of the light-harvesting chlorophyll a/b-binding protein of PSII was limited because of the limited supply of chlorophyll.

[A noteworthy case of postoperative liver metastasis from gastric cancer which responded well to UFT therapy]

A 66-year-old male underwent partial gastrectomy (resection of the pyloric side of the stomach) at another hospital on the basis of a diagnosis of gastric cancer (Fig. 1). Five months later, his CEA level began to rise. At that time, multiple liver metastases were detected by ultrasonography and CT scans. The patient received oral UFT therapy (400 mg/day) at our hospital. A reduction in CEA was observed 63 days after the start of this therapy. A judgment of CR (complete response) was made after 4 months of the therapy. At present, 2 years and 4 months after UFT was first administered, the patient shows no signs of tumor recurrence. This case is noteworthy since there has been no previous report of a case where UFT showed a high efficacy in treating liver metastasis after surgical resection of gastric cancer.

[Correlation between pyrimidine nucleoside phosphorylase (PyNPase) and clinicopathological factors in patients with gastric cancer]

Pyrimidine nucleoside phosphorylase (PyNPase) is a general term for enzymes which phosphorolyse pyrimidine class nucleosides; convert 5'-deoxy-5-fluorouridine (5'-DFUR), a fluoropyrimidine class anticancer drug, to an active type of 5-fluorouracil (5-FU); and demonstrate higher concentrations in tumor tissue. These findings have attracted attention from the standpoint of drug delivery systems. With regard to immunohistochemical staining studies, PyNPase expression correlated with cancer proliferation and metastasis. However, few have shown a relation between PyNPase assay and prognosis. We measured PyNPase value in tumor tissue of operative specimens from 60 gastric cancer patients. The results showed that the PyNPase value in tumor tissue was significantly higher (1.9 times) than in normal mucosa. There was no correlation between the PyNPase level in tumor tissue and clinicopathologic factors. However, many patients with relatively early gastric cancer had high enzyme levels, indicating that PyNPase may influence cancer proliferation and metastasis as well as prognosis. By detecting such a factor as PyNPase, and clinically applying the results, 5'-DFUR is promising for the treatment of patients with respect to prognosis.

The management of bleeding peptic ulcer in the elderly with heater probe thermocoagulation

BACKGROUND/AIMS

The aim of this study was to compare the clinical characteristics of bleeding peptic ulcers in the elderly with those in younger patients, retrospectively.

METHODOLOGY

Between 1986 and 1994, 274 patients with bleeding peptic ulcers were treated with heater probe endoscopically. They were divided into 2 groups: 48 in the elder group (70 years of age or older) and 226 in the younger group (<70). We evaluated the rate of concomitant disease, rebleeding rate, incidence of emergency surgery, mortality and blood transfusion requirement between the 2 groups.

RESULTS

The incidence of concomitant disease was significantly higher in the elderly group (83.3%) than in the younger group (33.3%) (p<0.01). The rate of rebleeding (younger group 23.5% vs. elderly group 31.3%), the incidence of emergency surgery (5.8% vs. 6.3%, respectively) and the rate of mortality due to hemorrhage (2.2% vs. 4.2%, respectively) were similar in the 2 groups. There was no significant difference in the mean volume of blood transfused.

CONCLUSIONS

It was revealed that aggressive endoscopic hemostasis improved the mortality rate and the incidence of emergency surgery in elderly patients as well as in younger patients, provided that their general condition was monitored carefully.

Role of platelet activating factor on severity of ischemic colitis

PURPOSE

Ischemic colitis develops after a sudden decrease in colonic blood supply and has a variety of clinical manifestations. The aim of this study was to assess the role of platelet activating factor in the pathogenesis of ischemic colitis with use of the platelet activating factor antagonist TCV-309.

METHODS

Rats were randomly divided into four groups. Rats in Group RV underwent ring attachment around the rectum to induce partial obstruction and ligation of the marginal vessels of the left colon. As control, rats in Group R underwent the ring attachment and rats in Group V underwent the vascular ligation. Rat in Group C underwent sham operation. The effects of TCV-309 on lesion formation in the colon were evaluated. Thiobarbituric acid reactant level was determined in colonic mucosa, and the incidence and severity of ischemic lesions were also determined.

RESULTS

Lesions of colitis were frequently observed in Group RV. TCV-309 did not prevent lesion formation, nor did it suppress the increase in thiobarbituric acid reactant level in Group RV. However, TCV-309 mitigated the severity of the lesion.

CONCLUSIONS

Partial obstruction of the colon tends to induce ischemic colitis, and additional ischemia completes lesion formation. Platelet activating factor may play a role in the progression of ischemic lesions.

Helicobacter pylori may cause "reflux" gastritis after gastrectomy

Patients with "reflux" gastritis after gastrectomy suffer from a variety of symptoms, and this type of gastritis may sometimes compromise the quality of life of these patients. Since Helicobacter pylori is considered to be one of the most important pathogenetic factors in gastritis, the association between H. pylori and reflux gastritis was investigated in this study. A total of 145 patients with gastrectomy were entered into the study. Five biopsy specimens from the gastric remnant were taken at upper gastrointestinal endoscopy. One specimen was examined pathohistologically, and the remaining four were examined for H. pylori infection. Fifty-two patients (36%) demonstrated H. pylori infection. The prevalence of H. pylori was significantly higher in patients who had a partial gastrectomy, and it was significantly lower in patients who had undergone gastrectomy more than 4 years previously. The histologic gastritis score in patients with H. pylori infection was significantly higher. Furthermore, H. pylori was eradicated in patients with some symptoms of gastritis and no bile reflux to the residual stomach at endoscopy; in these patients the symptoms were relieved and the histologic gastritis score decreased significantly. In conclusion, possible involvement of H. pylori is suspected in the pathogenesis of "nonreflux" gastritis after gastrectomy.

Impaired response of gastric vessels to prostaglandin E2 in rats with persistent obstructive jaundice

We investigated the response of gastric vessels to prostaglandin (PG) E2 after intra-duodenal release of bile in rats with obstructive jaundice. The animals were divided in four groups according to duration of bile duct obstruction (BDO): control and 1 week (W), 2W, and 3W groups. Prolonged BDO decreased gastric mucosal blood flow (BF) significantly. The BF recovered after the release of BDO in the 1W and 2W groups, but not in the 3W group. BDO decreased PGE2 content in gastric mucosa in the 1W, 2W, and 3W groups. PGE2 decreased vascular perfusion pressure of the isolated stomach in the control and 2W groups, but not in the 3W group. The response of gastric vessels to PGE2 was poor in the 3W group compared with the control and 2W groups. Decreased PGE2 in the gastric mucosa and decreased response of gastric vessels to PGE2 may affect gastric blood flow in obstructive jaundice.

Etiological involvement of Helicobacter pylori in "reflux" gastritis after gastrectomy

OBJECTIVES

"Reflux" gastritis after gastrectomy is associated with various symptoms that are often detrimental to the patients' quality of life. However, prevention of the reflux does not always bring relief from the symptoms of gastritis. Helicobacter pylori (H. pylori) is now considered one of the most important pathogenetic factors in gastritis. The association between H. pylori infection and reflux gastritis after gastrectomy was investigated in the present study.

METHODS

In total, 115 patients who had undergone gastrectomy were entered in this study. Five biopsy specimens from the gastric remnant were taken during upper GI endoscopy. One specimen was examined pathohistologically, and the remaining four were examined for H. pylori infection. The histological degree of gastritis was determined according to the score system of Rauws et al.

RESULTS

Forty-six patients (40%) demonstrated H. pylori infection in their stomachs. The prevalence of the infection was significantly higher in patients with conventional gastrectomy than in those with subtotal gastrectomy. The prevalence of H. pylori infection was significantly lower in patients who had undergone gastrectomy more than 4 yr ago. The histological gastritis score in patients with H. pylori infection was significantly higher than in those without H. pylori infection. Furthermore, the eradication of H. pylori in patients with both serious gastritis symptoms and no bile reflux improved the symptoms and significantly decreased the histological gastritis score.

CONCLUSIONS

The results suggest that H. pylori is a factor in the pathogenesis of reflux gastritis after gastrectomy.

Inhibitory effect of dopamine on gastric motility in rats

BACKGROUND

There is disagreement with regard to the involvement of dopamine (DA) receptors in gastric motility. The mechanisms of the inhibitory effect of DA on rat gastric motility was investigated in association with acetylcholine (Ach) release in the present study.

METHODS

In vivo vagotomized, splanchnicectomized rats and control rats were used, and gastric movement was determined as the gastric motility index after DA administration. In vitro study of Ach release from the circular muscle strips of the gastric corpus was investigated after administration of domperidone, SCH23390, phentolamine, or propranolol.

RESULTS

In the in vivo study DA inhibited gastric motility in a dose-dependent manner. Vagotomy and splanchnicectomy had no effect on the inhibitory effect of DA. In vitro study DA inhibited [3H]-Ach release in a dose-dependent manner. The inhibitory effect of DA was antagonized by domperidone but not by phentolamine, propranolol, or SCH23390.

CONCLUSIONS

Inhibition of gastric motility by dopamine is independent of extrinsic innervation and seems to be mediated by DA2 receptors in the gastric wall.

[Residual gastritis after gastrectomy and Helicobacter pylori--its clinical significance]

Residual gastritis after gastrectomy brings the various symptoms such as abdominal pain, nausea, emesis and loss of appetite, and often hazards quality of life of the patient. Bile reflux to the stomach is believed as one of the important pathogenesis of residual gastritis, however the prevention for bile reflux cannot always heal the gastritis. Helicobacter pylori (H. pylori) is considered as one of the most important pathogenesis of gastroduodenal ulcer and gastritis, and H. pylori may possibly cause residual gastritis after gastrectomy. However, the association between infection with H. pylori and the residual gastritis has not revealed yet. In the present study, the association with H. pylori and the residual gastritis after gastrectomy was investigated in 56 patients who had undergone gastrectomy before. Twenty-four patients (42.9%) had H. pylori infection at their stomachs and the incidence of the infection in the patients with gastrectomy was significantly higher with subtotal gastrectomy. As for the histological gastritis score of Rauws (Rauws' score), Rauws' score of H. pylori positive group was significantly higher than H. pylori negative group. Furthermore, the eradication of H. pylori for the patients with serious symptoms of gastritis improved the symptoms and decreased significantly Rauws' score. These results suggest that H. pylori was associated with the pathogenesis of residual gastritis after gastrectomy.

[Cytofluorometric chase of the cancer cells after release from G2-block induced by peplomycin]

To study the alteration of nuclear DNA content of cancer cells after peplomycin (PEP) treatment, DNA cytofluorometry was performed in combination with 3H-thymidine (3H-TdR) autoradiography using cultured A431 cells. The cells in the logarithmic growth were treated with PEP (1.25 micrograms/ml) for 24 hr, during the first 4 hr of which they were pulse-labeled with 3H-TdR (2.4 x 10(4) Bq/ml). After washing with PBS, the cells were then cultured without both PEP and 3H-TdR, fixed at different times and stained with propidium iodide (PI) for the auto-stage cytofluorometry, which enabled DNA content analysis for labeled and unlabeled cells by repeated scanning of the same cell population. The nuclear DNA content histograms demonstrated that A431 cells were mostly arrested in G2 phase of 4C stem line by treatment with PEP for 24 hr. This G2 block lasted up to 8 hr after removal of the drug, and thereafter, marked polyploidization associated with DNA synthesis occurred, showing almost no mitotic figures, while only a few cells returned to G1 phase via M phase. During the period of 72-120 hr, however, the fractions of advanced polyploid cells (DNA content > or = 8C) gradually decreased and the DNA content distribution pattern became eventually similar to the original one as seen before PEP treatment. From these results we hypothesized as follows: 1) At S-G2 boundary, there is some control mechanism that checks whether the cells, after S phase, can enter the M phase or not. 2) The cells, which are not permitted to enter mitosis by the control mechanism, show marked polyploidization. 3) Only the cells that enter into mitosis can live and proliferate, though the advanced polyploid cells die shortly. 4) This control mechanism might be related to the precision of DNA repair that is checked at the G2-M checkpoint.

[DNA-cytofluorometric, histopathological and immunohistochemical analyses of pancreatoduodenal cancers]

To study the cell characteristics of relatively small pancreatoduodenal cancers (less than 4 cm in the greatest dimension in histopathological examination), we analyzed the relation between the cell kinetics, and histopathological and immunohistochemical findings. Tumors were classified into t1 (0-2 cm in its greatest dimension) and t2 (2-4 cm). We analyzed DNA contents of five tumors of t1 and twelve of t2 by cytofluorometry. Histopathological and immunohistochemical (CA19-9 and CEA) examinations were also carried out. Nuclear DNA content histograms of the tumors in the t1 group showed all diploid pattern, while those in the t2 group exhibited 4 diploid, 7 euploid polyploid and 1 aneuploid patterns. Invasions to the lymphatic (ly), vein (v) and nerve (pn) were found in five cases of diploid tumors (3 of t1 and 2 of t2) and all (8 in t2) of non-diploid tumors. A medullary pattern of tumor growth was only noted in three tumors of t1. This pattern was not found in t2 (4 diploid, 8 non-diploid). These results suggest that the cellular DNA content increased in association with the tumor growth in size. In the histopathological findings, both the invasions (ly, v, pn) and fibrosis of the stroma more often appeared as the tumor size and polyploid and aneuploid cells increased. However, other histopathological findings and the immunohistochemical examination for CA19-9 and CEA had no relation to the tumor growth and the DNA ploidy pattern.

[Analysis of cell proliferation kinetics and the effects of cisplatin on the cell cycle of human gastric cancer cells by autostage cytofluorometry]

Analysis of both cell proliferation kinetics and effects of cis-diamminedichloroplatinum (CDDP) on cell cycle in human gastric cancer cell line (HGC-Y2) by measuring the contents of nuclear DNA, RNA and the Ki-67 antigen using autostage cytofluorometry system was described. In HGC-Y2 cells, RNA content increased during the cell cycle and reached to the maximum at G2/M phase. The results of pulse treatment with CDDP on these cells demonstrated a prolongation of S phase and G2 arrest with increasing of RNA content of these cells. We classified the cells by intranuclear distribution pattern of Ki-67 antigen and thus could identified the cells at G0 and M phases from these classification. The content of Ki-67 antigen was moderate grade at G1 phase and it decreased in the early S phase, then increased gradually during S phase and at the late S phase. It increased rapidly, reaching to the maximum at G2/M phase. After CDDP treatment, the content of Ki-67 antigen increased in the cells in prolonged S phase and in the cells arrested at G2 phase. It was also found that the syntheses of both Ki-67 antigen and RNA were not inhibited by CDDP. These results suggest that the method using autostage cytofluorometry system was useful for the research, on the mechanism of cancer therapy because of making possible to analyze precisely the cell cycle and the influence of anticancer drugs.

[The examination of DNA strand breaks induced by peplomycin-using non-radioactive in situ nick translation method]

In situ nick translation (ISNT) is a method to detect DNA single strand break (nick) at each cellular level. In this study, peplomycin (PEP)-induced DNA strand breaks and its repair were examined using non-radioactive ISNT method. Human fibroblasts were cultured with various concentrations of PEP for different durations, and then DNA strand breaks were evaluated by ISNT method. The signal intensity of DNA strand breaks of the PEP-treated fibroblasts was increased in a dose dependent manner. At the fixed concentration of PEP, it reached to a maximum level after 10 min. of culture and remained unchanged for at least 24 hours. In addition, DNA strand breaks induced by PEP was rapidly repaired in 10 min. after washing. Thus, the non-radioactive ISNT is thought to be a quick, sensitive and specific method not only to detect DNA strand breaks but also to observe its repair.

Evidence for a senescence-associated gene induced by darkness

A nearly full-length cDNA was isolated from a cDNA library prepared from incipiently senescent radish (Raphanus sativus L.) cotyledons using a previously isolated cDNA clone for dark-inducible mRNA as a probe (A Watanabe, N Kawakami, Y Azumi [1989] In Cell Separation in Plants, NATO ASI Series, Vol H35, pp 31-38. Springer-Verlag, Berlin). The clone detected transcripts of 800 bases which increased more than 100-fold after 24 hours of darkness. The transcripts also accumulated under light when plants were exposed to ethylene or heat stress, and (6)N-benzyladenine partially repressed its accumulation in the dark. These responses of the gene to physiological stimuli closely paralleled the effects of the stimuli on the progress of senescence of the cotyledons. We have named the gene din 1 (dark inducible gene 1). The cDNA encodes a polypeptide of 20 kilodaltons, and its nucleotide sequence shows a high (49%) similarity to a subfamily of pathogenesis-related proteins of tobacco. The predicted amino acid sequence of the product, however, shows only 20% homology to the pathogenesis-related protein.

Study of 16,16-dimethyl prostaglandin E2 for prevention of stress ulcer after hepatectomy of experimental cirrhotic liver and its influence on hepatic regeneration

The influence of 16,16-dimethyl prostaglandin E2 (16,16-dm PGE2; an agent used for the prevention of stress ulcer after hepatectomy of the cirrhotic liver) on liver regeneration after hepatectomy was studied in rats. The following results were obtained. Ulceration after the stress of 6 h of water immersion was markedly suppressed in rats treated with 30 r/kg of 16,16-dmPGE2 as compared with the untreated controls. In animals that received hepatectomy alone, the gastric pH and gastric mucosal blood flow showed significant reduction from the preoperative levels. In animals that received hepatectomy plus 16,16-dmPGE2 treatment the postoperative reduction in the gastric pH and gastric mucosal blood flow was suppressed, suggesting the effectiveness of 16,16-dmPGE2 treatment in the prevention of stress ulcer after hepatectomy of the cirrhotic liver. The 3H-thymidine uptake percentage and thymidine activity 24 h after hepatectomy and the DNA content 30 h after hepatectomy were significantly higher in animals treated with 16,16-dmPGE2 than in the untreated controls. In animals that were treated intraperitoneally with 50 mg/kg of indomethacin 6 h before hepatectomy the mitotic index 30 h after hepatectomy was markedly lower than that in untreated controls. This indomethacin-induced reduction in the mitotic index tended to be normalized by treatment with 16,16-dmPGE2. These results suggest that 16,16-dmPGE2 treatment effectively prevents stress ulcer and favorably affects hepatic regeneration after hepatectomy of the cirrhotic liver.

[The effect of cimetidine to suppress the reduction of gastric mucosal blood flow caused by immobilization in water--its relationship to noradrenaline]

Reduction of gastric mucosal blood flow has been regarded as being the most important event for the gastric defensive mechanisms. In male Wistar rats immobilized in water, the authors recently studied the effect of cimetidine on the gastric mucosal blood flow and the mechanism for that action of cimetidine. In vivo, animals were divided into four groups (PGE2-treated, PGI2-treated and cimetidine-treated groups and an untreated control group), and mucosal blood flow before and 4 hours after the start of immobilization was determined with the electrolytic hydrogen gas clearance technique. In vitro involving perfusion of the isolated gastric blood vessels, the effect of treatment with PGE2, PGI1 or cimetidine in the presence of stimulation with noradrenaline was assessed. The stress-caused blood flow reduction was significantly suppressed in the PGE2-treated group (26.9% reduction in blood flow), the PGI2-treated group (15.7%) and also in the cimetidine-treated group (39.2%) as compared to the controls in which blood flow was reduced by 58.0% following immobilization. In vitro, cimetidine treatment resulted in a reduction of gastric perfusion pressure by 36.6% at maximum although the reduction was more marked following treatment with PGE2 (44.9% reduction) or PGI2 (49.4%). This result suggests that cimetidine also has a vasodilative action.

The mechanism of acute gastric ulcer after induced hemorrhagic shock

Changes in gastric mucosal blood flow were investigated for their relationship to gastric mucosal prostaglandin E2 (PGE2) and noradrenaline (NA) in rats with hemorrhagic shock. The results were as follows: 1) Gastric mucosal blood flow and NA decreased after hemorrhage. Gastric mucosal PGE2 initially increased after exsanguination and then markedly decreased. 2) Administration of NA before hemorrhage resulted in an increase of PGE2. However, the PGE2 value for animals receiving NA after hemorrhage was not different from that of non-NA-treated group. 3) Pre-treatment with PGE2 suppressed the reduction in both gastric mucosal blood flow and NA and the development of ulcer. These results suggest that the increase in gastric mucosal PGE2 in the early stage of shock might represent a phenomenon of adaptation by the adrenergic activation, and the decrease in PGE2 in the late stage might result from impaired synthesis of PGE2 due to persistent hypoxia and might be one of the possible factors in ulcer formation.

Experimental study of vagotomy for prevention of stress ulcer after hepatectomy of cirrhotic livers. Its influence on hepatic regeneration

We experimentally studied the influence of vagotomy on hepatic regeneration in rats after hepatectomy of cirrhotic livers. In animals that underwent hepatectomy plus vagotomy the reduction in gastric pH was suppressed, but gastric mucosal blood flow was less than that in control animals that received hepatectomy alone. The suppression of 3H-thymidine uptake percentage and thymidine kinase activity after hepatectomy was more marked in animals treated with hepatectomy plus vagotomy than in controls treated with hepatectomy alone. Hepatic DNA level tended to be lower in animals treated with hepatectomy plus vagotomy than in controls. In animals treated with hepatectomy plus vagotomy, the peak level of the mitotic index was lower and the hepatic regeneration rate was evidently suppressed. These results suggest that it is not appropriate to apply vagotomy, during hepatectomy of cirrhotic livers, for the prevention of postoperative stress ulcer because it causes a marked reduction in gastric mucosal blood flow and suppresses hepatic regeneration.

Evolutionary dynamics of tryptophan tRNAs in Mycoplasma capricolum

Mycoplasma capricolum uses two tryptophan codons, the "universal" nonsense codon UGA and the universal codon UGG. The bacterium contains two tryptophan tRNAs, one with anticodon UCA, (U: 2'-O-methyl U derivative), and the other with CCA (5'-C: partially 2'-O-methylated). tRNAUCA would translate codons UGA and probably UGG by wobbling. tRNACCA is much less charged by tryptophan in the cells than tRNAUCA, and the intracellular amount of tRNACCA is 5-10 times lower than that of tRNAUCA. The genes for these two tRNAs are separated by a terminator-like structure in a single operon. In vitro transcription experiments suggest that the predominance of tRNAUCA over tRNACCA results from the attenuation of transcription by this terminator-like structure.

[Experimental study on mechanism of onset of acute ulcer viewed from blood coagulation and activities of fibrinolysis after hepatectomy in liver cirrhosis]

Using liver cirrhosis rats induced by intraperitoneal administration of 4% thioacetamide (TAA) consecutively for 10 weeks, the authors made a study on the activities of blood coagulation and fibrinolysis in the onset of acute ulcer after hepatectomy. The results were as follows: 1. On the 3rd day after hepatectomy increase in the portal blood pressure, approximate 30% decrease in gastric wall blood flow and increase in fibrinolysis in blood and gastric mucosa were observed. While no bleeding was recognized, edema and hyperemia were noticeable. 2. On the 3rd postoperative day when the maximum increase of fibrinolysis in blood and gastric mucosa was observed water immersion restraint stress was loade. Two hours after loading, fibrinolysis in blood and tissue increased further, and in accordance with it, bleeding and erosion were seen to a high degree in gastric mucosa. On the other hand, in the EACA group, in which anti-fibrinolytic agent, epsilon-amino carpic acid was administered, the increase was moderate in the fibrinolysis in blood and mucosa after loading the stress. Though bleeding and development of erosion were not completely controlled, values of fibriolytic activity of the tissue in the EACA group were lower than those of control group.

[Efficacy of vagotomy on liver regeneration in the prevention of stress ulcer after partial hepatectomy in the cirrhotic rat]

Possible effects of vagotomy (a means of preventing stress ulcers after partial hepatectomy in cirrhotic liver) on liver regeneration were explored. Cirrhosis was induced in rats by means of intraperitoneally administering 4% thioacetamide for 10 consecutive weeks. These rats were subjected to partial hepatectomy (ca. 68% resection) and vagotomy at the same time. Normal rats of consistent age served as controls after receiving hepatectomy. In controls, which received hepatectomy alone, both gastric pH and gastric wall blood flow showed a significant reduction on the third day after surgery. In animals which received both hepatectomy and vagotomy, postoperative reduction in gastric pH was suppressed, but postoperative reduction in gastric wall blood flow was more marked compared to those of controls. In animals which received both hepatectomy and vagotomy, postoperative 3H-thymidine intake and thymidine kinase activity were markedly suppressed compared to controls. In animals which received both hepatectomy and vagotomy, the peak level of mitotic index and the hepatic regeneration rate were markedly suppressed compared to those of controls. The above results indicate that vagotomy is not advantageous to liver regeneration and prevention of stress ulcer after partial hepatectomy in cirrhotic rat because of its potency of inducing marked reduction in gastric wall blood flow and impediment of liver regeneration.

UGA is read as tryptophan in Mycoplasma capricolum

UGA is a nonsense or termination (opal) codon throughout prokaryotes and eukaryotes. However, mitochondria use not only UGG but also UGA as a tryptophan codon. Here, we show that UGA also codes for tryptophan in Mycoplasma capricolum, a wall-less bacterium having a genome only 20-25% the size of the Escherichia coli genome. This conclusion is based on the following evidence. First, the nucleotide sequence of the S3 and L16 ribosomal protein genes from M. capricolum includes UGA codons in the reading frames; they appear at positions corresponding to tryptophan in E. coli S3 and L16. Second, a tRNATrp gene and its product tRNA found in M. capricolum have the anticodon sequence 5' U-C-A 3', which can form a complementary base-pairing interaction with UGA.