Tetsuo Nemoto

Increased expression of matrix metalloproteinase 7 and 9 and membrane type 1-matrix metalloproteinase in esophageal squamous cell carcinomas.

The 5‐year survival rate of patients with submucosal (sm) esophageal carcinoma continues to be much worse than that with intramucosal (m) lesions. The reasons are unclear, but matrix metalloproteinases (MMPs) and membrane type matrix metalloproteinases (MT‐MMPs) are known to be involved in degradation of extracellular matrix macromolecules associated with tumor cell invasion. Expression of these enzymes may have some relation to the difference in survival between patients with sm and m esophageal carcinomas.

Overexpression of Protein Tyrosine Kinases in Human Esophageal Cancer

Using a PCR-based cloning technique, we isolated a series of protein tyrosine kinases (PTKs) expressed in a cell line of esophageal squamous cell carcinoma. Sequence analysis revealed 10 different kinds of PTKs of the receptor type [epidermal cell growth factor receptor, insulin-like growth factor I receptor, fibroblast growth factor receptor 4, eck, erk, discoidin domain receptor (DDR)/trkE/cell adhesion kinase (Cak), HEK2, HEK8, axl and sky] and one PTK of the nonreceptor type (tyk2). Subsequently, we examined the expression of the transcripts of these 11 genes in paired samples of normal and carcinomatous esophageal tissues obtained from 12 cases of esophageal cancer. We found that all 11 gene transcripts were expressed in both carcinomatous and normal tissues, and 6 of them were significantly overexpressed in carcinomatous tissues relative to adjacent normal tissues. Among these, the magnitude of mRNA expression of DDR/trkE/Cak PTK was positively correlated with the proliferative activity of carcinoma cells, but not with their degree of differentiation. Immunohistochemically, DDR was expressed in both normal and cancerous esophageal cells. The intensity of the expression was higher in cancer than normal tissue. In addition, we confirmed the expression of two isoforms of DDR/trkE/Cak in normal and cancerous esophagus. Our study suggests that DDR/trkE/Cak plays an important role in the regulation of proliferation of esophageal cancer.

Loss of Syndecan‐1 and Increased Expression of Heparanase in Invasive Esophageal Carcinomas

Heparan sulfate proteoglycans play important biological roles in cell‐cell and cell‐matrix adhesion, and are closely associated with growth factor actions. Loss of syndecan‐1, a cell surface‐bound heparan sulfate proteoglycan, has been reported for advanced head and neck carcinomas, and expression of endoglycosidic heparanase, which cleaves heparan sulfate glycosaminoglycans (HS‐GAGs), is associated with invasion and metastatic potential of malignant tumors. Paraffin sections of 103 primary esophageal squamous cell carcinomas were immunohistochemically examined for the expression of syndecan‐1 core protein, HS‐GAGs and heparanase protein, and the results were compared with various clinicopathological parameters, such as invasion depth. For 16 cases, fresh tumor samples were quantitatively analyzed for heparanase and syndecan‐1 mRNA expression by real‐time RT‐PCR in addition to the immunohistochemical studies. Syndecan‐1 core protein and HS‐GAGs expression was significantly decreased in pT2 and pT3 cases compared with their pTis and pTl counterparts. Decreased expression of core protein and HS‐GAGs was correlated with the incidence of lymphatic invasion, and venous involvement. Furthermore, decreased expression of HS‐GAGs was correlated positively with the incidence of nodal metastasis and distant organ metastasis, and negatively with the grade of tumor cell differentiation. The percentage of cytoplas‐mic heparanase protein‐positive cases increased significantly in pT2 and pT3 cases compared to that in pTis and pTl cases, and this was associated with lymphatic invasion, and venous and lymph nodal involvement. The level of heparanase mRNA was inversely correlated with the degree of HS‐GAGs expression rather than core protein. In conclusion, loss of syndecan‐1 and heparanase overexpression in esophageal squamous cell carcinomas are closely associated with malignant potential. Regarding the mechanism of loss of HS‐GAGs, heparanase upregulation appears to play an important role.

Coronary artery lesions in Takayasu arteritis: Pathological considerations

SummaryThis communication reviews the clinical and pathological features of coronary artery lesions in Takayasu arteritis. The incidence of coronary artery involvement has been reported to be 9% to 10%, and is observed mainly in autopsy cases because coronary artery disease is usually not evident until the occurrence of angina pectoris or myocardial infarction, or after the onset of congestive heart failure. On the basis of pathological features, the following three types of coronary artery lesions can be distinguished: type 1, stenosis or occlusion of the coronary ostia and the proximal segments of the coronary arteries; type 2, diffuse or focal coronary arteritis, which may extend diffusely to all epicardial branches or may involve focal segments, so-called skip lesions; and type 3, coronary aneurysm. Most of the coronary artery lesions in Takayasu arteritis are of type 1. Narrowing of the coronary arteries is mainly due to the extension of the inflammatory processes of proliferation of the intima and contraction of the fibrotic media and adventitia from the ascending aorta. In some cases, coronary stenosis may be caused by coronary arteritis as skip lesions in Takayasu arteritis, but even in these cases the lesions have been reported to affect mainly the proximal segments of the coronary arteries. Diffuse lesions of the coronary artery and coronary artery aneurysm seem to be very rare in Takayasu arteritis. Other causes of coronary ostial stenosis, coronary arteritis and coronary artery aneurysm are also discussed.

Long-term outcome of bladder papillary urothelial neoplasms of low malignant potential

To evaluate the long‐term outcome of bladder papillary urothelial neoplasms of low malignant potential (PUNLMP).

Expression of Matrix Metalloproteinase-9 and Bombesin:Gastrin-Releasing Peptide in Human Prostate Cancers and their Lymph Node Metastases

Neuroendocrine differentiation and subsequent excretion of neuropeptides have been demonstrated to be associated with progression of human prostate cancer. Among neuropeptides found to exist in the prostate, bombesin/gastrin-releasing peptide has been shown to upregulate matrix metalloproteinase-9 (MMP-9) in human prostate cancer cell lines. Expression levels of bombesin, MMP-9, and neuron-specific enolase were examined by immunohistochemistry in 41 cases of clinically organ-confined prostate cancers including 9 with microscopic lymph node metastases. Twenty-seven (64%) of the 41 radical prostatectomy specimens were positive for both MMP-9 and bombesin. Expression of these molecules was observed in almost the same population of the cancer cells. The remaining 14 cases were negative for both MMP-9 and bombesin. High-grade tumors (Gleason sum U 7) were more likely to express MMP-9 and bombesin (21/24 : 88%) than low-grade tumors (Gleason sum S 6) (7/17 : 41%). In eight of the nine cases with pathological lymph node metastases, expression of MMP-9 and bombesin was also noted in metastatic sites. Neuron-specific enolase was positive in 16 cases (39%) and not always associated with the expression of bombesin. Expression of bombesin and expression of MMP-9 are common in human prostate cancers and may be related to an aggressive phenotype.

Proliferative activity and p53 protein accumulation correlate with early invasive trend, and apoptosis correlates with differentiation grade in oesophageal squamous cell carcinomas

Using oesophageal squamous cell carcinoma samples of both intramucosal and advanced types, proliferative activity (Ki-67 labelling index), p53 protein accumulation and apoptosis (in situ DNA nick end labelling) were assessed, and the relation of these values to progression or differentiation grade of tumours was analysed. In terms of proliferative activity and the proportion of positive cases with p53 accumulation, a statistically significant difference was demonstrated between intraepithelial carcinomas and intramucosal carcinomas with stromal invasion (17.2% vs 31.7% for the Ki-67 labelling index, and 23.5% vs 67.4% for the proportion of positive cases of p53 accumulation). Values for the latter were almost comparable to those of advanced carcinomas. Immunohistologically, Ki-67 positive, proliferating cells were distributed preferentially in the peripheral fronts of invading nests. Apoptotic cells were observed in the inner areas of the invading nests of the intramucosal carcinomas with stromal invasion and in more advanced lesions, but were rarely observed in the normal epithelium or intraepithelial carcinomas. Apoptotic cells were seen mainly around areas of keratinization, and the apoptotic cell index was higher in well and moderately differentiated types of advanced carcinomas than in the poorly differentiated type (2.59% vs 1.09%). An increase in proliferative activity and an accumulation of p53 protein are associated with the onset of early carcinomatous invasion, while apoptosis is closely linked with the differentiation grade of carcinoma cells.

Expression of the cyclin dependent kinase inhibitor p21WAF1/CIP1 in oesophageal squamous cell carcinomas

Abstract To elucidate the role of CDK inhibitor p21WAF1/CIP1 in human oesophageal squamous cell carcinomas, we examined its expression immunohistochemically using surgically resected tissues from 25 patients, and have analyzed the relationship with alteration of p53 gene (F-SSCP analysis), proliferative activity (Ki-67 labelling index), frequency of apoptosis (in situ DNA nick end labelling), and degree of differentiation. P21 expression was observed in 11 cases (44%) with a percentage of positive cells ranging between 1% and 10%. Of the 25 cases, 4 cases showed >5% of positive cells. As for the relationship with p53 gene, all 7 p53-mutation positive cases were negative for p21 expression, whereas 11 out of 18 mutation negative cases showed positive for p21 expression. As for the relationship with degree of tumour differentiation, 6 out of 8 well differentiated type cases showed positive for p21 expression. By contrast, all 8 cases of poorly differentiated type were negative for p21 expression. Frequency of apoptotic cells was significantly higher in p21 positive cases than negative cases although Ki-67 labelling index was almost the same regardless of the expression of p21. P21 expressing cells were distributed mainly in the middle layers of the invading nests, especially around the keratinization, which was almost similar to the distribution of apoptotic cells. Our results suggest that expression of p21 in human oesophageal squamous cell carcinomas is induced by a p53-dependent pathway and affects apoptosis and differentiation of carcinoma cells.

GIANT EPIPHRENIC DIVERTICULUM WITH ACHALASIA OCCURRING 20 YEARS AFTER HELLER'S OPERATION

We report a case of giant epiphrenic diverticulum in a 43-year-old woman who underwent Hellers myotomy because of achalasia 20 years earlier. She complained of heartburn and dysphagia from March of 1991 and was hospitalized in our institution. An upper gastrointestinal X-ray examination with contrast medium revealed a large hemispheric lesion (7.8×4.8cm) occupying the right posterior wall of the lower thoracic and abdominal esophagus. Manometry revealed a motility disorder and high pressure of the lower esophageal sphincter due to achalasia. Therefore she was diagnosed as having a giant diverticulum with achalasia after Hellers operation. She underwent transhiatal esophagectomy and reconstruction with placement of a gastric tube on June 4, 1992. Pathology results on the resected specimen revealed a false diverticulum. She has been doing well for 4 years since the operation.It has been said that a complication of incomplete long myotomy causes pulsion diverticulum, but we could not find a case of epiphrenic diverticulum after myotomy for achalasia reported in the literature in the last 10 years.

Coexpression of heparanase, basic fibroblast growth factor and vascular endothelial growth factor in human esophageal carcinomas

Heparan sulfate (HS), which is degraded by heparanase, plays an important role in cell adhesion, insolubility of the extracellular matrix (ECM) and as a reservoir for various growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). In the present study, we examined the immunohistochemical expression of heparanase, bFGF and VEGF, and evaluated the correlation between their expression and microvessel density (MVD) in human esophageal carcinomas. Heparanase, bFGF and VEGF were immunolocalized predominantly to the carcinoma cells, but they were also localized to the endothelial cells of microvessels near the carcinoma cell nests. In carcinomas with invasion of the muscular layer or adventitia, heparanase staining was stronger at the invasive areas of carcinomas than the intraepithelial spread. Expression of heparanase and bFGF and the degree of MVD were associated  with  tumor  invasion,  lymph  node  metastasis  and pathological stages. Cases with positive staining for heparanase, bFGF or VEGF tended to have a higher MVD than those without staining, and carcinomas with concomitant expression of heparanase, bFGF and VEGF showed the highest MVD. The level of heparanase mRNA expression was directly correlated with the MVD. In addition, heparanase‐positive cases had a higher positive ratio of bFGF and VEGF compared with the heparanase‐negative cases. These data suggest the possibility that heparanase may contribute to not only cancer cell invasion but also angiogenesis probably through degradation of HS in the ECM and release of bFGF and VEGF from the HS‐containing ECM.