Sialyl-lewis-x antigen immunoreaction of colorectal-cancer and its relationship to hematogenous metastasis

The adhesion of cancer cells to endothelial cells of the target organ is one of the most important steps of hematogenous metastasis. Especially, sialyl Le(X) plays an important role in defining the metastasis. The expression of sialyl Le(X) antigen in colorectal cancer and its usefulness not only as an indicator of metastatic potential but also as a prognostic factor was studied immunohistochemically. Fifty-five (32.4%) sialyl Le(X) antigen-positive tumors were found in 170 colorectal cancers. There was a significant correlation between the expression of sialyl Le(X) antigen and the histological tumor type, venous invasion, lymph node metastasis, as well as liver metastasis. Hematogenous metastases were significantly more frequent in patients with sialyl Le(X)-positive tumor than in those with sialyl Le(X)-negative tumor; and prognosis was significantly poorer in the former. The results suggest that sialyl Le(X) antigen plays a role in hematogenous metastasis of colorectal cancer, and that the expression of sialyl Le(X) is associated with poor prognosis.

Inhibition of liver metastasis formation by anti-CD44 variant exon 9 monoclonal antibody

The overexpression of variants of the glycoprotein CD44 is thought to be associated with the tumorigenesis and progression of human cancers. We examined the role of the variant CD44v8-10 in the metastasis of the human colon cancer cell line HT29 using a monoclonal antibody (mAb 44-1V) reactive with the v9 product. After immunization with mAb 44-1V, the growth of HT29m cells in vitro was not retarded. Six-to 8-week-old mice were divided into 4 groups for liver metastasis assay. All animals in control groups injected with intrasplenic HT29m developed metastases. In contrast, only one of the animals injected with HT29m that reacted with mAb 44-1V developed a metastatic tumor in the liver. The intravenous administration of mAb 44-1V after intrasplenic HT29m injection did not inhibit the formation of liver metastasis. In addition, the adhesiveness of the HT29m cells to the basement membrane matrix was decreased by treatment with the anti-CD44v9 mAb. These findings indicated that a CD44 variant containing the products of variants of exons v8-10 may play an important role in adhesion of tumor cells to the capillaries of distant organs in the metastatic process.

Effects of micro-encapsulation on morphology and endocrine function of cryopreserved neonatal porcine islet-like cell clusters

BACKGROUND

For the success of clinical islets transplantation, the development of a long-term storage method is necessary. However, the structure of digested islets is scanty for culture and cryopreservation. In this study, the effect of micro-encapsulation to cryopreserved porcine islet-like cell clusters (ICCs) was investigated.

METHODS

The ICCs prepared from neonatal pigs by collagenase digestion and culture technique were cryopreserved and micro-encapsulated in 5% agarose membranes. After cryopreservation, ICC cultured without encapsulation (group A) and cultured with encapsulation (group B) were assessed by comparison with no cryopreserved ICC (control) both in vitro by static incubation test and in vivo in a xenotransplantation study.

RESULTS

Micro-encapsulation was able to maintain the fine morphology and the number of ICCs of group B after 7 days of culture. There were not significant differences in insulin secretion of group B and control on day 1 and 7 of culture (1 day:11+/-0.99, 7 days: 5.30+/-1.08 microU/ICC/hr NS versus control). On day 7 of culture, the retrieval rate of group B (105.2+/-9.8%) is obviously higher compared with group A (63.0+/-6.3%). In the xenotransplatation model, the ICCs of group B showed long survival time (7.9+/-0.4 weeks) and good transplantation effect.

CONCLUSION

Our study suggests that micro-encapsulation is one of the useful method for cryopreserved ICC to maintain the fine morphology and effectively recover the endocrine function.

Expression of DCC protein in colorectal tumors and its relationship to tumor progression and metastasis

A loss of heterozygosity (LOH) at the DCC gene locus was detected in colorectal tumors, and this LOH might be related to metastasis. The aim of this study was to determine DCC protein expression in colorectal cancer and to evaluate its prognostic value. Allelic loss of the DCC locus was observed in 16 of the 23 patients (66.7%). In all 16 patients with LOH, DCC expression was decreased in the cancer tissue compared with the adjacent normal mucosa. All 23 colorectal tumors had decreased expression of this protein relative to the adjacent normal colonic mucosa in Western blot analysis. The levels of DCC protein were significantly lower in cancer tissues than in adenoma tissues. Decreased DCC protein expression was also observed by immunohistochemistry in the colorectal cancer cases. There were significant correlations between DCC protein expression and histologic type, venous invasion, and hematogenous metastasis. Patients with DCC-protein-negative tumors had a greater relative risk of recurrence compared with those whose tumors were DCC protein-positive. The 5-year survival rate was 91.0% in patients with DCC-protein-positive tumors, and 58.8% in those with DCC-protein-negative tumors; these differences between the two groups of patients were significant (p < 0.01). In multivariate analysis using the Cox regression model, DCC protein expression emerged as an independent prognostic indicator. These findings suggested that a decrease in DCC expression may have an important role in the progression of colorectal cancers and may be a biologic marker of prognostic significance.

Efficacy of continuous hyperthermic peritoneal perfusion for the prophylaxis and treatment of peritoneal metastasis of advanced gastric cancer: evaluation by multivariate regression analysis

Thirty-two patients with advanced gastric cancer underwent continuous hyperthermic peritoneal perfusion (CHPP) combined with surgery: to prevent peritoneal recurrence in 15 patients without peritoneal metastasis (prophylactic CHPP) and to treat 17 patients with peritoneal metastases (therapeutic CHPP). The postoperative outcome was compared with that of control patients treated with surgery alone. Peritoneal recurrence was less frequent (26%) and the 5-year survival rate was significantly higher (39%) in the patients with prophylactic CHPP than in 40 control patients (42 and 17%, respectively). The patients with therapeutic CHPP showed significantly better median survival than did 20 control patients (11 vs. 6 months). Cox multivariate regression analysis revealed that CHPP was an independent prognostic factor in the prophylactic study (hazard ratio = 0.3965), and that the independent prognostic factor in the therapeutic study was not CHPP but complete resection of the peritoneal metastasis. Thus, CHPP has no marked benefit for established peritoneal metastasis. CHPP for the prevention of peritoneal recurrence may have a beneficial effect on long-term survival, but a prospective randomized trial is needed to clarify its prognostic value.

Surgical results of pancreaticoduodenectomy for carcinoma of the distal third of the stomach

Pancreaticoduodenectomy (PD) was performed as a radical operation on 10 patients who had stage III or IV carcinoma of the distal third of the stomach which invaded the pancreas head (T4) or had level 3 lymph node metastasis. The surgical results of the PD were compared with those of 69 patients treated with subtotal gastrectomy (SG). Although the postoperative morbidity was higher (70%) in the PD group than in the SG group (32%), no hospital death occurred. The overall postoperative survival provided by PD was as good as that provided by SG for 43 patients who had stage III or IV tumors (the 5-year survival rates, 40 versus 45%). Regarding the T4 tumors invading the pancreas, the survival of the 9 patients with PD was better than that of the 12 patients with SG (median survival time, 19 versus 9 months). Thus, PD might improve the postoperative survival of patients with carcinoma of the distal stomach invading the pancreas.

[A case of stage IV (N4) esophageal cancer successfully treated with concurrent chemoradiotherapy]

A 71-year-old man with inoperable intrathoracic esophageal cancer was treated by concurrent chemoradiation. A dose of 48 Gy (neck) and 60.6 Gy (mediastinum) and four courses of 5-FU (500 mg/day)-CDDP (50 mg/week) were delivered. The esophageal tumor and metastatic lymph nodes of the neck showed a complete response (CR) to the treatment, whereas paraaortic lymph nodes evidenced no change (NC). The patient is doing well without symptoms at 13 months after treatment. The chemoradiotherapy produced effective improvement and quality of life in this patient.

Clinical significance of combined immunohistochemical detection of CD44v and sialyl LeX expression for colorectal cancer patients undergoing curative resection

To evaluate their prognostic value, the expressions of CD44v and sialyl LeX (SLX) in colorectal cancers were studied immunohistochemically. Tissue specimens were reacted with monoclonal antibodies (mAb) CD44-1V and CSLEX-1. Of the 145 colorectal cancer patients undergoing curative resection, 59 (40.7%) were positive for mAb CD44-1V, and 40 (27.6%) were positive for mAb CSLEX-1. There was a significant correlation between the combined expression of SLX and CD44v8-10 and lymph node metastasis. The patients with tumors negative for CD44v8-10 and SLX had the most favorable prognoses. Conversely, the patients with tumors positive for both CD44v8-10 and SLX had a high recurrence rate and the poorest prognoses. In a multivariate analysis using the Cox regression model, the combined expression of SLX and CD44v8-10 emerged as an independent prognostic indicator. These results suggested that the combined expression of CD44v8-10 and SLX may be a biologic marker of prognostic significance.

Expression of nm23-H1 gene and Sialyl Lewis X antigen in breast cancer

The nm23 gene has been proposed as a candidate tumor metastasis suppressor in some human cancers. Sialyl Lewis X (sLex) has been demonstrated to play an important role in the adhesion of human cancer cells to human vascular endothelium, inducing metastasis. Little information has been reported about the correlation between the expression of nm23 and sialylated carbohydrate antigens. In the present study, 102 surgically resected primary breast cancer tissues were sectioned and stained with antibody against nm23-H1 and sLex. Of the 102 cases, 39 (38.2%) cases with a reduced expression of nm23-H1 were observed, and the numbers of sLex-positive cases were 61 (59.8%), respectively. The reduced expression of nm23-H1 and the positive expression of sLex were significantly associated with lymph node involvement. Among the 100 patients who underwent curative surgery, the disease-free survival rate was significantly correlated to both the nm23-H1 and sLex expressions. No interrelated expressions were found between nm23-H1 and sLex. In multivariate analysis using Cox regression model, combination assay of nm23-H1 and sLex expression emerged as independent significant prognostic factors. These results suggest that nm23-H 1 gene and sLex may be involved in different steps of the metastatic process in human breast cancer, and immunohistochemical detection of the combination of sLex and nm23-H1 may be a biologic marker of prognostic significance.

Prognostic value of DNA ploidy and proliferating cell nuclear antigen in gastric cancer

DNA ploidy and the labeling index (LI) of proliferating cell nuclear antigen (PCNA) in gastric cancers were determined using cytofluorometry and immunohistochemistry, respectively, and the prognostic value of these two parameters was evaluated. Of 66 patients with advanced gastric cancers treated with radical resection, 27 with aneuploidy and a high PCNA-LI (> or = 40) showed the lowest 5-year survival rate (38%). Twenty patients with diploid cancers and a high LI showed a lower 5-year survival rate (59%) than the 15 patients with diploid cancers and a low LI (<40), who had the highest 5-year survival rate (86%). A multivariate analysis showed that the grouping based on the ploidy and the LI was an independent prognostic factor. Thus, the combination of DNA ploidy and PCNA-LI may be a useful prognostic indicator for advanced gastric cancers.

Clinical significance of serum levels of CD44 variant exons 8-10 protein in colorectal cancer

We examined serum levels of a CD44 splice variant that contained variant exons 8-10 (CD44v8-10) as a tumor marker in colorectal cancer patients. We performed enzyme-linked immunosorbent assays in 81 sera obtained from 71 colorectal cancer patients and 10 healthy controls. Serum CD44v8-10 levels were significantly higher in the colorectal cancer patients than in the healthy controls (0.209 +/- 0.098 versus 0.114 +/- 0.019 OD; P < 0.01). There was a close correlation between immunohistochemical expression and serum CD44v8-10 levels. Surgical resection of the tumors resulted in a reduction of serum CD44v8-10 levels. There was no significant correlation between serum CD44v8-10 level and serosal invasion or histologic type. However, a significant correlation was observed between serum CD44v8-10 level and lymphatic or venous invasion. In addition, serum CD44v8-10 levels were significantly higher in carcinomas associated with lymph node or liver metastasis than in those without metastasis. These findings suggest the usefulness of serum CD44v8-10 level in the prediction of colorectal cancer metastasis.

[Telomerase activity in colorectal carcinoma and its relationship to clinicopathological findings]

Telomerase is thought to be responsible for cell immortality. The telomerase activity in carcinomas has been remarked since 1995. We examined telomerase activity in colorectal carcinoma by TRAP (Telomeric repeat amplification protocol) assay, and investigated its relationship to clinicopathological findings. We could analyse telomerase activities in 33 cases (66%) of 50 colorectal carcinomas, whereas the activity was not found in all 13 cases of noncancerous colorectal mucosa. There was no relation between the telomerase activity and the clinicopathological findings or metastatic status. We confirmed telomerase activities in much of colorectal carcinomas in spite of their progression. The carcinoma cells might be immortal from their early stage of progression by means of telomerase activity.

Preservation of pancreatic islets in rodent models

Islet-cell transplantation has some advantages over vascularized pancreas transplantation, but data from clinical islet cells transplantation have shown that some serious problems need to be overcome. One of them is the storage of islet cells. We investigated methods of preserving islet cells using culture-preservation and cryopreservation. Cryopreservation is thought to be effective for long-term preservation of large quantities of islet cells, because they can be cryopreserved without loss of their physiologic activity using a relatively rapid cooling rate of 25 degrees C/min. Moreover, in the allogenic transplantation models of cryopreservation of dissociated islet cells, there was a significant prolongation of survival time. These results suggest that cryopreservation of islet cells involves not only variable preservation methods but may also lead to a modification of graft immunogenicity.

Usefulness of metyrapone treatment to suppress cancer metastasis facilitated by surgical stress

BACKGROUND

One causative factor of tumor metastasis enhanced by surgical stress is thought to be hypersecretion of endogenous glucocorticoids. This study evaluated the effectiveness of metyrapone treatment and adrenalectomy in preventing the harmful effects of glucocorticoids in the enhancement of tumor metastasis resulting from surgical stress.

METHODS

The effect of dexamethasone on pulmonary metastasis of MRMT-1 cells and on the number of peripheral lymphocytes was evaluated in rats. To evaluate the suppressive effect of adrenalectomy and metyrapone treatment on operation-induced enhancement of metastasis, several parameters such as induction of pulmonary metastasis, serum corticosterone levels, and the number of blood lymphocytes and apoptotic thymocytes were determined.

RESULTS

With dexamethasone treatment, the number of peripheral lymphocytes rapidly decreased; in contrast, pulmonary metastasis increased. The serum corticosterone level was doubled at 1 hour, apoptotic thymocyte numbers were increased about sevenfold at 3 hours and about fourfold at 6 hours, and blood lymphocyte numbers were decreased at 3 hours after laparotomy, which facilitated about a 10-fold increase in the pulmonary metastasis. These changes were almost completely suppressed by preoperative adrenalectomy and metyrapone treatment.

CONCLUSIONS

Preoperative metyrapone treatment, which suppresses hypersecretion of endogenous glucocorticoids as a result of operation, modulates the enhancement of cancer metastases and may be an effective treatment.

Reduced expression of deleted colorectal carcinoma (DCC) protein in established colon cancers

Using a bacterial fusion protein, a deleted colorectal carcinoma (DCC)-specific monoclonal antibody (MAb) 127-22 was established. Although MAb 127-22 reacted with almost all normal tissues, it did not react or only weakly reacted with many cancer cell lines, including colonic cancer lines, in flow cytometry. In Western immunoblots, the MAb reacted with a single 190-kDa molecule in a myeloma line Ara-10 extract. This component was scarcely detected in colonic cancer cell lines. Immunoblots of samples from 25 pairs of colonic cancers and adjacent normal tissues and from five adenoma tissues revealed that all normal colonic and adenoma tissues significantly expressed the DCC protein, whereas colonic cancer tissues showed poor expression. These results indicate not only deletion of and lowered mRNA expression of the DCC gene, but also marked reduction of DCC protein occurred in colonic cancer tissues. In addition, colonic cancer patients with liver metastasis expressed significantly lower levels of DCC than those without, suggesting the prognostic value of DCC expression.

Significance of tumor marker SLX in colorectal cancer

We examined serum SLX for its significance as a tumor marker in 109 colorectal cancer patients. There a close correlation with immunohistochemical expression of SLX and serum SLX level. Serum SLX was positive in 16.5% of 109 patients with colorectal cancers. There was no significant correlation between serum SLX level and histologic type or primary tumor status. There were significant correlations between serum SLX positive rates and both lymph node and hematogenous metastasis. In 7 SLX positive cases who underwent curative resection, 4 patients had already recurrence in the liver. Our findings suggest that serum SLX values may be a biologic marker of metastasis.

Lectin-histochemical reactivity of sialic acid in breast cancer and its relationship to prognosis using limulus polyphemus agglutinin

Studies of circulating sialic acid have revealed its relationship with a variety of malignant tumors. It is not vet clear whether sialic acid could be used as a prognostic marker of breast cancer, and few studies have examined sialic acid expression in the cell membrane and cytoplasm of breast cancer cells by means of the lectin-histochemical technique. In the present study, we used biotinylated limulus polyphemus agglutinin (LPA), a special binding lectin of sialic acid, to stain sialic acid in breast cancer cells. Of the 104 cases of breast cancer examined, 59 (56.7%) positive cases were observed. There was a significant correlation between the LPA staining and the clinicopathologic features of all patients, including pathological stage and lymph node metastasis. Among the 100 patients who underwent curative operation, the mean disease-free survival rate of the 45 patients who were LPA-negative was significantly higher than that of the 55 LPA-positive patients (p<0.05). These results suggest that the positive expression of sialic acid in breast cancer could be used as a marker of malignancy potential, as well as a poor survival factor, and the biotinylated LPA assay may provide a convenient and useful method to predict the prognosis of breast cancer.

The role of lymph node dissection in the treatment of gallbladder carcinoma

BACKGROUND

Lymph node involvement is an important prognostic factor in gallbladder carcinoma (GBC). The lymph node involvement pattern, extent, and indications for systematic lymph node dissection for patients with advanced GBC were investigated.

METHODS

Forty-one patients with GBC who underwent radical resection with systematic regional lymph node dissection over the past 11 years were analyzed.

RESULTS

The lymph node metastasis rate was 63.4% overall, 0% in pT1 disease, 61.9% in pT2 disease, and 81.3% in pT3/pT4 disease. When reviewed according to site, the rate was 41.5% in pericholedochal lymph nodes, 22.0% in the lymph nodes around the common hepatic artery and the portal vein, 36.6% in the posterior pancreaticoduodenal lymph nodes, 28% (5/18) in the celiac lymph nodes, 19% (3/ 16) in the superior mesenteric artery (SMA) lymph nodes, and 26% (7/27) in the aortocaval paraaortic lymph nodes. Patients with severe hepatoduodenal ligament invasion had high rates of paraaortic lymph node involvement. The mortality rate was 2.4% (1 of 41 patients) and the 5-year survival rate was 33.1% overall, 100% in patients with pT1 disease, 49.8% in patients with pT2 disease, and 0% in patients with pT3/pT4 disease. The 5-year survival rate for pT2 disease according to lymph node involvement was 72.7% in patients with pN0+ pN1+ positive posterior pancreaticoduodenal lymph nodes and positive lymph nodes around the common hepatic artery in the N2 patients and 0% in the patients with positive celiac and SMA lymph nodes in the N2 patient group or the positive paraaortic lymph node group (P < 0.05).

CONCLUSIONS

These results suggest that systemic dissection of N1 lymph nodes, posterior pancreaticoduodenal lymph nodes, and lymph nodes around the common hepatic artery and the portal vein in N2 patients is necessary to improve the prognosis of those patients with pT2 disease without moderate or severe hepatoduodenal ligament invasion.

The role of lymph node dissection in the treatment of gallbladder carcinoma

BACKGROUND

Lymph node involvement is an important prognostic factor in gallbladder carcinoma (GBC). The lymph node involvement pattern, extent, and indications for systematic lymph node dissection for patients with advanced GBC were investigated.

METHODS

Forty-one patients with GBC who underwent radical resection with systematic regional lymph node dissection over the past 11 years were analyzed.

RESULTS

The lymph node metastasis rate was 63.4% overall, 0% in pT1 disease, 61.9% in pT2 disease, and 81.3% in pT3/pT4 disease. When reviewed according to site, the rate was 41.5% in pericholedochal lymph nodes, 22.0% in the lymph nodes around the common hepatic artery and the portal vein, 36.6% in the posterior pancreaticoduodenal lymph nodes, 28% (5/18) in the celiac lymph nodes, 19% (3/ 16) in the superior mesenteric artery (SMA) lymph nodes, and 26% (7/27) in the aortocaval paraaortic lymph nodes. Patients with severe hepatoduodenal ligament invasion had high rates of paraaortic lymph node involvement. The mortality rate was 2.4% (1 of 41 patients) and the 5-year survival rate was 33.1% overall, 100% in patients with pT1 disease, 49.8% in patients with pT2 disease, and 0% in patients with pT3/pT4 disease. The 5-year survival rate for pT2 disease according to lymph node involvement was 72.7% in patients with pN0+ pN1+ positive posterior pancreaticoduodenal lymph nodes and positive lymph nodes around the common hepatic artery in the N2 patients and 0% in the patients with positive celiac and SMA lymph nodes in the N2 patient group or the positive paraaortic lymph node group (P < 0.05).

CONCLUSIONS

These results suggest that systemic dissection of N1 lymph nodes, posterior pancreaticoduodenal lymph nodes, and lymph nodes around the common hepatic artery and the portal vein in N2 patients is necessary to improve the prognosis of those patients with pT2 disease without moderate or severe hepatoduodenal ligament invasion.

The role of lymph node dissection in the treatment of gallbladder carcinoma

BACKGROUND

Lymph node involvement is an important prognostic factor in gallbladder carcinoma (GBC). The lymph node involvement pattern, extent, and indications for systematic lymph node dissection for patients with advanced GBC were investigated.

METHODS

Forty-one patients with GBC who underwent radical resection with systematic regional lymph node dissection over the past 11 years were analyzed.

RESULTS

The lymph node metastasis rate was 63.4% overall, 0% in pT1 disease, 61.9% in pT2 disease, and 81.3% in pT3/pT4 disease. When reviewed according to site, the rate was 41.5% in pericholedochal lymph nodes, 22.0% in the lymph nodes around the common hepatic artery and the portal vein, 36.6% in the posterior pancreaticoduodenal lymph nodes, 28% (5/18) in the celiac lymph nodes, 19% (3/ 16) in the superior mesenteric artery (SMA) lymph nodes, and 26% (7/27) in the aortocaval paraaortic lymph nodes. Patients with severe hepatoduodenal ligament invasion had high rates of paraaortic lymph node involvement. The mortality rate was 2.4% (1 of 41 patients) and the 5-year survival rate was 33.1% overall, 100% in patients with pT1 disease, 49.8% in patients with pT2 disease, and 0% in patients with pT3/pT4 disease. The 5-year survival rate for pT2 disease according to lymph node involvement was 72.7% in patients with pN0+ pN1+ positive posterior pancreaticoduodenal lymph nodes and positive lymph nodes around the common hepatic artery in the N2 patients and 0% in the patients with positive celiac and SMA lymph nodes in the N2 patient group or the positive paraaortic lymph node group (P < 0.05).

CONCLUSIONS

These results suggest that systemic dissection of N1 lymph nodes, posterior pancreaticoduodenal lymph nodes, and lymph nodes around the common hepatic artery and the portal vein in N2 patients is necessary to improve the prognosis of those patients with pT2 disease without moderate or severe hepatoduodenal ligament invasion.

Distribution of vagal preganglionic neurons in the rat brain innervating thoracic and abdominal organs revealed by retrograde DiI tracing

To investigate the distribution and number of preganglionic neurons which regulate motility and secretion in thoracic and abdominal organs in the vagal parasympathetic nervous system, the neuronal tracer DiI was injected into the organs and the distribution of retrogradely labeled neurons was examined in the rat brainstem. The stomach received the vast majority of efferent projections from the dorsal motor nucleus of the vagus nerve (DMV). The cecum and the duodenum also received projections from the DMV, but they originated from a smaller number of preganglionic neurons. Preganglionic neurons projecting to the stomach occupied the middle part of the DMV, those projecting to the cecum occupied the lateral part of the DMV, and those projecting to the duodenum were found in the medial edge of the DMV. The ventral and dorsal sides of the stomach wall were innervated by the left and right vagus nerves, respectively. However, immediately after passing the boundary between the stomach and duodenum, the left and right vagal nerve fibers mixed in the ventral and dorsal walls of the distal gastrointestinal tract. The nucleus ambiguous is a mixture of parasympathetic preganglionic neurons and motoneurons. In this study, we revealed that the major targets of these preganglionic neurons were the lungs and other thoracic organs.

[Effective transcatheter arterial embolization for hepatic metastasis in a case of AFP producing gastric cancer]

We experienced a case of effective transcatheter arterial embolization (TAE) for hepatic metastasis in a AFP producing gastric cancer. A 51-year-old man with 2 type gastric cancer (H0) underwent subtotal gastrectomy (D2). The serum AFP level was 134.3 ng/ml, and AFP positive tumor cells were detected by PAP method. After the operation, the serum AFP level initially decreased but re-increased on the 7th postoperative month, and metastatic lesions of the liver were detected by CT scan. After the patient was treated 4 times by TAE, the serum AFP level returned within normal range and the metastatic tumors of the liver decreased markedly. Therefore liver resection was performed at the 28th month after the first operation. Total necrosis of metastatic liver lesions was confirmed. This patient has been well without recurrence signs for 10 years since operation. It is concluded that TAE should be used to treat hepatic metastasis in the case of an AFP producing gastric cancer.

[A study about the mechanism of hepatocyte injury induced by endotoxin--interaction of Kupffer cells and polymorphonuclear neutrophils (PMNs)]

Focusing our attention on the TNF (tumor necrosis factor) produced by Kupffer cells (KCs). The role of KCs and polymorphonuclear neutrophils (PMNs) in endotoxin (LPS)-induced hepatocellular injury was investigated. This study used the culture fluid supernatant of KCs which had been stimulated with LPS as the "LPS stimulation supernatant", and evaluated hepatocellular injury as ornithine carbamyl transferase percent leakage. There was no difference between groups I (HCs: hepatocytes) and II (HCs + PMNs), but there were differences between groups I and III (HCs + LPS stimulation supernatant, groups II and IV (HCs + LPS stimulation supernatant + PMNs), and III and IV. There was no significant difference between III and V (III + anti-TNF antibody), but a difference was found between IV and VI (IV + anti-TNF antibody). These findings suggest that PMNs activated by KCs-generated TNF as well as KCs-derived humoral factors other than TNF play a role in the development of LPS-induced hepatocellular injury.

[Liver resection in a case of multiple liver metastases of gastric cancer following hepatic arterial infusion chemotherapy]

A 61-year-old-man underwent subtotal gastrectomy (D2) for advanced gastric cancer with multiple liver metastases. After the operation, repeated hepatic arterial infusion chemotherapy was performed employing implantable catheter and port system with CDDP and MMC. The result was that the liver tumors showed a remarkable regression in size, and the serum CA 19-9 level decreased within normal range. But the tumor in the lateral segment grew and the CA 19-9 level increased again. There was no evidence of metastasis or recurrence except in the liver, and the metastatic tumors in right lobe became smaller by hepatic arterial infusion chemotherapy at this time. Therefore, lateral segment resection was performed for reductive surgery 14 months after the first operation. After that, the liver tumors did not grow and CA 19-9 kept within the normal range, while hepatic arterial infusion chemotherapy could be given. Thus, it seems that liver resection for reduction surgery following hepatic arterial infusion chemotherapy should be considered as a treatment for multiple liver metastases.

Expression of a CD44 variant containing exons 8 to 10 is a useful independent factor for the prediction of prognosis in colorectal cancer patients

PURPOSE

To determine the expression of the CD44 variant containing a variant exon 8 to 10 product (CD44v8-10) in colorectal cancer and to evaluate its prognostic value.

MATERIALS AND METHODS

CD44v8-10 was studied in resected tumors and normal mucosae obtained from 215 colorectal cancer patients (118 colon cancer and 97 rectal cancer). The expression of CD44v8-10 was analyzed immunohistochemically using the anti-CD44v8-10 monoclonal antibody (mAb) 44-1V.

RESULTS

One hundred of 215 cancer tissues expressed CD44v8-10. Positive staining was intense mainly on the cell membranes. There was no significant correlation between expression of CD44v8-10 and histologic type, primary tumor, lymphatic invasion, venous invasion, or peritoneal invasion. There were significant correlations between CD44v8-10 immunoreactivity and both lymph node and hematogenous metastasis. Patients with CD44v8-10-positive tumors had a greater relative risk of death compared with those whose tumors were CD44v8-10-negative. Among 169 patients who underwent curative resection, CD44v8-10 expression correlated with a high recurrence rate. The 5- and 10-year survival rates were 90.3% of patients with CD44v8-10-negative tumors, and 72.1% and 58.0% of those with CD44v8-10-positive tumors, respectively; these differences between the two groups of patients were significant (P < .01). In multivariate analysis using the Cox regression model, CD44v8-10 expression emerged as an independent prognostic indicator.

CONCLUSION

The results suggest that CD44v8-10 plays a role in metastasis of colorectal cancer, and tha CD44v8-10 expression may be a biologic marker of prognostic significance.

Expression of CD44 variant exons 8-10 in gastric cancer

The expression of CD44 variant containing variant exons 8-10 product (CD44v8-10) was studied by western blot analysis and immunohistochemistry in gastric cancers using a monoclonal antibody, 44-1V. On western blots, a single band of 130 kD was recognized in stomach cancer cell lines. CD44v8-10 expression, with reactivity localized in the cell membrane, was found in 65 (33.5%) of the 194 advanced gastric cancers. There was no correlation between CD44v8-10 immunoreactivity and serosal, lymphatic, or lymph node invasion. However, there was significant correlation with CD44v8-10 immunoreactivity and venous invasion. CD44v8-10-positive cancers were more frequently associated with hematogenous metastasis than those which were immunonegative. There was an inverse association between CD44v8-10 immunoreactivity and peritoneal dissemination, especially in diffuse type adenocarcinomas. These observations indicate that CD44v8-10 may play a role in the metastasis of gastric cancer.

Predicting the viability of grafted livers in rats through a rapid and sensitive metabolic indicator assessed by 31P-NMR spectroscopy

The present study was undertaken to clarify whether a correlation exists between the hepatic ratio of the beta-phosphorus moiety of ATP (beta-ATP) to inorganic phosphate (Pi), measured by 31P nuclear magnetic resonance spectroscopy 1 h after the reestablishment of portal blood flow, and the survival rate of rats following liver transplantation. This ratio was compared with the arterial ketone body ratio [AKBR (acetoacetate/3-hydroxybutyrate)], which is accepted as a reliable indicator of liver viability. After the transplantation of fresh livers, the 1-week survival rate was 92% and the beta-ATP/Pi ratio was 64% of the normal level. When the liver grafts were subjected to warm ischemia for 25 min or 45 min prior to harvesting, the 1-week survival rate decreased to 43% and 0%, respectively, and the beta-ATP/Pi ratio dropped to 31% and 18% of the normal level, respectively. On the other hand, the AKBR was about 25% of the normal level after transplantation of fresh livers, while it was 37% and 48% after transplantation with 25 min and 45 min of warm ischemia, respectively. However, 4 h after the reestablishment of portal blood flow, the AKBR correlated with the beta-ATP/Pi ratio in both the fresh graft group and the 45-min warm ischemic damage group. These results show that the beta-ATP/Pi ratio provides an accurate evaluation of a graft viability even at an extremely early stage following liver transplantation, and should prove useful for the early diagnosis of primary graft nonfunction after liver transplantation.

[The role of CD44 adhesion molecules]

CD44 is a transmembrane glycoprotein involved in the interaction between cells and extracellular matrix. CD44 is ubiquitously expressed on cells, and has been thought to be a cell adhesion molecule with proposed functions in extracellular matrix binding, cell migration and lymphocyte homing. In 1991, Stamenkovic et al. showed the existence of two forms of CD44: a hematopoietic (standard) and an epithelial form which was highly expressed by carcinomas. The alternative splicing of 10 variant exons encoding the membrane proximal portion of the external domain of CD44, in particular, results in many variant isoforms. These may play a critical role in malignant behavior and in determining organ specificity in metastasis.

Possible involvement of protein-tyrosine kinases such as p72syk in the disc-sphere change response of porcine platelets

We previously reported that p72syk, a non-receptor tyrosine kinase, was activated maximally at 10 s after thrombin or thromboxane A2 stimulation, even in platelets that were not allowed to aggregate [Taniguchi et al. (1993) J. Biol. Chem. 268, 2277-2279; Maeda et al. (1993) Biochem. Biophys. Res. Commun. 197, 62-67]. Then, the change in the shape of porcine platelets induced by the thromboxane A2 analogue, STA2, and the role of protein-tyrosine kinases including p72syk in this response were evaluated, using the shape-change parameter. We show that p72syk activation is correlated with the disc-sphere change in a time- and dose-dependent manner following stimulation by STA2. Tyrphostin B44, a potent protein-tyrosine kinase inhibitor, reduced the thromboxane A2-evoked p72syk activation and the disc-sphere change in a dose-dependent manner. Furthermore, the translocation of p72syk to the cytoskeleton-rich fraction and an increase in the tyrosine phosphorylation of an about 120 kDa protein were observed during the disc-sphere change induced by STA2. These lines of evidence suggest that the activation of protein-tyrosine kinases such as p72syk may be involved in the disc-sphere change response in thromboxane A2-stimulated porcine platelets.

[A case of duodenal duplication and a review of reported cases]

We report a case of duodenal duplication and review of literatures on 43 cases reported in Japan including ours. A 34-year-old female who was admitted with chief complaints of epigastric pain and hematoemesis. An endoscopic examination and a hypotonic duodenography revealed a protruding tumor with bleeding ulcer. Wedge resection of the duodenum, including the lesion, was performed. A diagnosis of duodenal duplication was made by histopathological examination.

[Quality of life in patients with advanced gastric cancer receiving AO-90, a methionine-free intravenous amino acid solution, with 5-fluorouracil and mitomycin C]

We conducted a randomized, multicenter, controlled trial of AO-90, a methionine-free 7.43% intravenous amino acid solution, in patients with advanced recurrent gastric cancer. The regimen used in the study was comprised of two-week treatment cycles, with a withdrawal period between cycles. During treatment, patients were given either AO-90 (500-750 ml/day; AO/MF group) or a commercial amino acid solution (600-800 ml/day; C/MF group) by total parenteral nutrition (TPN) for 14 days concomitantly with MF therapy (5-fluorouracil 350 mg/m2/day, iv continuously for 14 days and mitomycin C 7 mg/m2, iv push on days 7 and 14). We interviewed 118 eligible and evaluable patients (72 men and 46 women; 59 cases in the AO/MF group and 59 in the C/MF group) about their quality of life immediately before the start of treatment, one week and two weeks after the start of treatment, and one week and two weeks after treatment. A 11-item questionnaire was used to interview the subjects: nine questions using a five-point scale, one question using a 100-mm linear visual analog scale, and one question using a five-grade face scale. Changes in the grades compared with baseline data were scored as 1 point (improvement of one grade or more, or 20 mm or more), 0 points (no changes), and-1 point (decline of one grade or more, or 20 mm or more). Before analyzing the significance, quality of life score data were adjusted by the Mantel-Haenszel method due to uneven distribution of subjects concerning baseline performance status and complications. Among the items questioned, subjects receiving AO-90 showed significantly higher scores in appetite, nausea, and ambulation at some evaluation time points than those receiving a methionine-containing TPN. The results show that AO-90 improved the quality of life of patients with advanced recurrent gastric cancer.

[A controlled study of AO-90, a methionine-free intravenous amino acid solution, in combination with 5-fluorouracil and mitomycin C in advanced gastric cancer patients (surgery group evaluation)]

The results of recent preclinical and clinical studies suggest that AO-90, a methionine-free intravenous amino acid solution (7.43%), potentiates the antitumor effect of 5-fluorouracil (5-FU). In the present multi-center, randomized, controlled study conducted at the surgery departments of 53 institutions between July 1991 and March 1993, patients with advanced gastric cancer were randomly allocated to receive either AO-90 (500-750 mL/day, AO/MF group) or Amiparen, a commercial intravenous amino acid solution (600-800 mL/day, C/MF group) by total parenteral nutrition for 14 days. Both groups received MF therapy which consisted of a continuous infusion of 5-FU at 350 mg/m2/day for 14 days and an i.v. push of mitomycin C 7 mg/m2 on days 7 and 14 (one course). Additional treatment courses were initiated after a withdrawal period when appropriate. Of the 138 subjects enrolled, 129 (93.5%) were eligible and 119 (86.2%) completed the scheduled treatment (AO/MF group: 57, C/MF group: 62). The overall clinical response rates in the completed cases were 26.3% (15/57) in the AO/MF group and 8.1% (5/62) in the C/MF group, and the difference between the groups was significant (p = 0.015). In particular, the response rate in the postoperative recurrent patients with measurable lesions was 42.9% (12/28) in the AO/MF group versus 12.0% (3/25) in the C/MF group (p = 0.016). Further, in the patients who were previously treated with fluoropyrimidine drugs, 29.0% (9/31) responded to the AO/MF therapy versus 8.6% (3/35) in the C/MF group (p = 0.053). The treatment-related adverse reactions observed were mainly hematologic and subjective/objective symptoms, such as decreased leukocyte count and hemoglobin level, nausea/vomiting and stomatitis. The differences in the incidence were not significant between the groups. Based on these results, AO-90 in the MF regimen appears to be effective in the treatment of patients with advanced gastric cancer by significantly potentiating the effects of 5-FU.

Relationships among the expression of epidermal growth factor receptor, proliferating cell nuclear antigen labeling index, and lymph node metastasis in gastric cancer

The expression of epidermal growth factor receptor (EGFR), epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha) and the labeling index of proliferating cell nuclear antigen (PCNA LI) were examined immunohistochemically in 288 gastric cancer patients, and the relationships between these results and the lymph node metastasis were studied. To investigate the relation between the expression of EGFR and PCNA LI, we divided the patients into the following three groups according to the immunohistochemical findings: group A, EGFR (+); group B, EGFR (-), and EGF(+) or TGF alpha(+); group C, EGFR(-), EGF(-) and TGF alpha(-). In the cancers invading submucosal or proper muscle layer, high-PCNA tumors (PCNA LI > or = 70) in both groups A and B had more frequent lymph node metastasis than in the intermediate-(40-69) and low- (< or = 39) PCNA tumors. In the cancers invading subserosal layer or further, the frequency of metastasis in group A was over 78% and was not related to the PCNA range. In group B, metastasis was more frequent in high- and intermediate-PCNA tumors (about 80%) than in low-PCNA tumors (44%). These results suggest that growth regulation by EGFR is related to lymph node metastasis in gastric cancer, and the higher the PCNA LI of cancer cells becomes, the more frequent the occurrence of lymph node metastasis.

Expression of CD44 variant exons 8-10 in colorectal cancer and its relationship to metastasis

Splice variants of CD44 are overexpressed in human lung, breast, and colon carcinoma cell lines. This study was conducted to clarify the association between the expression of CD44 variant exons 8-10 and metastatic potential in human colorectal cancer. We found that the expression of a CD44 splice variant containing exons v8-10 was increased in all of 60 colorectal cancer specimens examined compared with matched normal colerectal mucosa, as determined by Northern blotting. Expression of CD44 variant exons 8-10 did not significantly correlate with histological type, depth of tumor invasion, lymphatic invasion, venous invasion, or lymph node metastasis. However, the level of CD44 variant exon 8-10 expression was significantly higher in carcinomas associated with liver metastasis than in those without liver metastasis. In addition, expression of CD44 variant exons 8-10 in the liver metastases was more intense than that in the primary colorectal cancers. These findings indicated that this domain of the CD44 glycoprotein encoded by exons v8-10 may play an important role in tumor hematogenous metastasis of human colorectal cancer.

Expression of human nm23-H1 and nm23-H2 proteins in hepatocellular carcinoma

BACKGROUND

The expression of nm23-H1 and nm23-H2 proteins in 25 hepatocellular carcinomas was studied immunohistochemically.

METHODS

Tissue specimens were reacted with anti-human nm23-H1 and nm23-H2 monoclonal antibodies (MoAb) (H1-229 and H2-206, respectively) and then stained by the biotin-streptoavidin complex method.

RESULTS

Adjacent nontumorous tissues were intensely stained with nm23-H1 and nm23-H2. Of the 25 hepatocellular carcinomas, 60% were positive for MoAb H1-229, and 68% were positive for MoAb H2-206. These immunoreactivities were most common in the cytoplasm of tumor cells. There was no significant correlation between the expression of nm23-H1 protein and tumor size, Edmondson's histopathologic classification, or invasion of the capsule. However, the authors observed an inverse relationship between nm23-H1 expression and intrahepatic metastases of hepatocellular carcinomas. There was no significant correlation between the expression of nm23-H2 protein and clinicopathologic findings. Only a short survival period was observed in patients with hepatocellular carcinoma with reduced nm23-H1 or nm23-H2 proteins.

CONCLUSIONS

The results suggest that nm23-H1 protein plays a role in the suppression of intrahepatic metastasis of hepatocellular carcinoma and that the combined expression of nm23-H1 is associated with favorable prognosis.

Overexpression of p53 protein and proliferative activity in colorectal adenoma

Overexpression of p53 was studied immunohistochemically in colorectal tumors. We found p53-positive cells in 17 (58.6%) of 29 specimens of cancer in adenoma. Expression of p53 protein was detected in the nuclei of the tumor cells. We also found p53-positive cells in 7 (7.1%) of 99 specimens of adenoma. p53 immunoreactivity for severe dysplasia was higher than that for mild or moderate dysplasia. p53 expression in adenomas was restricted to a few glands, and the proliferating-cell nuclear antigen (PCNA)-positive rate for the p53-positive glands was significantly higher than that for p53-negative glands. The results suggested that the p53-positive glands might have high growth fractions, and that immunohistochemical detection of p53 expression in tubular adenomas might contribute to identifying the potential for malignant transformation.

[Expression of human epidermal growth factor and its receptor of the gastric carcinomas with special reference to DNA ploidy patterns and nucleolar organizer regions]

In 68 cases of surgically resected gastric carcinomas, expression of human epidermal growth factor (EGF) and its receptor (EGFR) were examined immunohistologically using the Avidin-Biotin Peroxidase Complex Method, and their relation with DNA contents and nuclear protein synthesis in the tumor progression were studied by measuring DNA ploidy patterns and nucleolar organizer regions (NORs), respectively with cytofluorometry and AgNO3 stain method. EGF and EGFR expression were respectively found only in 2 (7%) and 1 (4%) in 28 early cancers, and significantly increased in advanced cancers, 25 (63%) and 9 (23%) out of 40 cases. The ratio of aneuploid tumor and the NORs numbers per tumor cell also increased in advanced cancers, compared with in early cancers. EGF and EGFR respectively expressed in 19 (51%) and 9 (23%) in 37 aneuploid cancers, significantly more frequent than 8 (26%) and 1 (3%) in 31 diploid cancers. In the EGF-positive tumors, the NORs numbers showed 4.11 +/- 0.72, significantly higher than 2.68 +/- 0.61 in the EGF-negative tumors. These results suggested that expression of EGF and EGFR in the gastric carcinomas increases during the tumor progression from the early to advanced stage, stimulates synthesis of DNA and nuclear protein, and consequently enhances (strengthens, heightens, or intensifies) the proliferative activity of the tumors.

Protein-tyrosine kinase p72syk is activated by thromboxane A2 mimetic U44069 in platelets

We show that p72syk is rapidly activated following the stimulation of thromboxane A2 mimetics, U44069 and STA2 in porcine platelets. The activity of p72syk reached a maximum at 10 s and decreased to a basal level within 60 s after 1 microM U44069 stimulation. This activation was enhanced in a dose-dependent manner and completely canceled by the pretreatment of platelet suspension with ONO3708, a specific antagonist of thromboxane A2. Pretreatment of platelets with aspirin as well as apyrase did not affect the activation of p72syk. When both extra- and intra-cellular Ca2+ were depleted, the activation of p72syk was still persistent; in contrast, the deactivation process was completely abrogated even at 120 s after U44069 stimulation. These results suggest that p72syk is a responsible enzyme to the protein-tyrosine phosphorylation events, and that p72syk functions mainly before Ca2+ recruitment in thromboxane A2-stimulated platelets.

Inverse association of nm23-H1 expression by colorectal cancer with liver metastasis

The expression of nm23-H1 mRNA and protein was studied in colorectal cancers by Northern blotting and immunohistochemistry. All 21 colorectal cancers studied by Northern blotting had increased levels of nm23-H1 mRNA relative to the adjacent normal colonic mucosa. Increased nm23-H1 protein expression was also observed in all 36 colorectal cancer cases including those studied by Northern blotting. There was no significant correlation between nm23-H1 expression and tumour histology, serosal invasion, lymphatic invasion, venous invasion, or lymph node metastasis. However, the expression of both mRNA and protein was significantly lower in tumours associated with liver metastasis than in those without such metastasis. These observations indicate that the nm23 gene may play a role in the suppression of liver metastasis of colorectal cancer.

Colonic prostaglandin-e2 in carcinogenesis in rats with N-methyl-n'-nitrosoguanidine

The effects of prostaglandin E2 and indomethacin on carcinogenesis were studied in male Wistar rats. Of the rats, those treated with MNNG (MNNG group) were given 1 ml of 0.1% solution of MNNG in distilled water by intrarectal instillation every day for 14 days. The diet for the rats treated with Indomethacin and MNNG (Indo-MNNG group) was supplemented with 0.005% indomethacin. No tumor was found in a group of controls. Tumor incidence was 43.8% at week 20 and 81.8% at week 40 of treatment for the MNNG group whereas, it was 5.3% at week 20 and 27.8% at week 40 for the Indo-MNNG group. These differences were of statistical significance (p<0.01). Tumor incidence per animal was lower for the Indo-MNNG group: a mean of 0.50 tumors/animal, compared with 2.18 tumors/animal for the MNNG group (p<0.01). PGE2 levels in colonic mucosa were: 23.9 (pg/mg total protein) at week 5: 27.8 at week 10; 33.2 at Week 20, and 34.8 at week 40 for the control group. It was 44.7 at week 5; 43.1 at week 10; 70.1 at week 20, and 79.7 at week 40 for the MNNG group. Intrinsic PGE2 levels in noncancerous mucosa were significantly higher for the MNNG group than for the control group at all stages of observation. PGE2 significantly decreased in the Indo-MNNG group. with mean values of 22.0 at week 5; 29.0 at week 10; 43.1 at week 20, and 40.6 at week 40, compared with the MNNG group. These findings demonstrated that PGE2 of colonic mucosa promoted the development and proliferation of carcinoma in MNNG-induced large bowel carcinogenesis in rats.

p53 immunoreaction in endoscopic biopsy specimens of colorectal cancer, and its prognostic significance

The expression of p53 protein was immunohistochemically studied in formalin-fixed paraffin-embedded biopsy specimens of 203 colorectal carcinomas by use of a monoclonal antibody specific for the p53 protein. PAb1801. p53 protein expression with its reactivity localised in nuclei was found in 121 (59.6%) of the cancers. There was no correlation of p53 immunoreactivity with histological classification, wall invasion, lymphatic invasion, venous invasion, lymph node metastases, or peritoneal metastases. p53-positive cancers were more frequently associated with liver metastasis than p53-negative ones. Patients with p53-positive tumours had significantly poorer prognoses than those with p53-negative tumours. The 5 year survival rate was 58.1% for patients with p53-positive tumours, and 76.3% for those with p53-negative tumours. In Dukes' stage C tumours, an especially good correlation was found between p53 immunoreactivity and prognosis. In addition, patients with p53-positive tumours had higher recurrence rates. The results indicate that p53 immunoreactivity may be a useful prognostic marker of colorectal cancers.

[Modes of spread and surgical strategy for gallbladder carcinoma with subserosal invasion]

The mode of spread and the prognosis were investigated in 22 patients with resected gallbladder carcinoma invading the subserosal layer. By the Kaplan-Meier method, the 5-year survival rate was 68.8% in patients receiving curative or relatively noncurative resection. On the other hand, no patient survived for more than 3 years after noncurative resection. The mode of subserosal infiltration was classified according to the general rules for gastric cancer study. At least systemic lymph node dissection (R2) should be performed in patients with ss alpha cancer, because lymph node metastasis in these patients were confined to the 1st group. More extensive lymph node dissection (R2 with 9, 16) is essential for patients with ss beta and ss gamma, because lymph node metastasis to at least the 2nd group were seen in 75% of them. The surgical margin was positive for cancer in all patient with infiltration of the hepatoduodenal ligament. Therefore, it was considered that hepatoligamentectomy should be performed in these patients to obtain a cancer free surgical margin. Among patients undergoing curative or relatively noncurative resection, the recurrence rate was 43% in those with lymph node metastasis and 50% in those with DNA aneuploidy. Therefore, it appears that adjuvant chemotherapy should be given to such patients.

Dimethyl sulfoxide (DMSO) increases expression of sialyl Lewis x antigen and enhances adhesion of human gastric carcinoma (NUGC4) cells to activated endothelial cells

Dimethyl sulfoxide (DMSO) exerts a number of biological effects including the promotion of cell differentiation in cultured cells. In this study, we examined the effect of DMSO on the adhesion of tumor cells to endothelial cells. In vitro treatment of human gastric adenocarcinoma (NUGC4) cells with DMSO resulted in increased adhesion to interleukin-I (IL-I)-activated human endothelial cells compared with DMSO-untreated NUGC4 cells. In flow cytometry, treating NUGC4 cells with DMSO enhanced the expression of sialyl Lewis x (sialyl Le(x)) and sialyl dimeric Le(x) antigens on their surface. Also, the binding of Limulus polyphemus agglutinin (LPA), which specifically binds to cell-surface sialic acids, was increased by DMSO. The adhesion of DMSO-treated NUGC4 cells to activated endothelial cells was blocked by neuraminidase pre-treatment of tumor cells or by antibody against either endothelial leukocyte adhesion molecule-I (ELAM-I) or sialyl Le(x). Thus, it is suggested that enhanced adhesion following DMSO treatment is mediated by the interaction of sialyl Le(x) expressed on NUGC4 cells with ELAM-I of endothelial cells. The modulation of sialyl Le(x) antigen by DMSO provides a useful system for studying the regulatory mechanism of Lewis-related carbohydrate antigens and also for understanding the metastatic properties of cancer cells.