Keisuke Iihara

Immunohistochemical evaluation of E-cadherin adhesion molecule expression in human gastric cancer.

E-cadherin (ECD) is one of subclasses of the cadherin family which plays a major role in the maintenance of intercellular adhesion in epithelial tissues. An immunohistochemical study of ECD expression was performed on gastric adenocarcinoma from 103 patients using our monoclonal antibody for human ECD (HECD-1). ECD was strongly expressed in normal gastric epithelium without exception; however, various staining patterns were observed in cancer tissues. The frequency of tumours with preserved ECD expression (Pre-type) and reduced ECD expression (Rd-type) was 42% and 58% respectively. Tumours with a high frequency of Rd-type expression particularly included: undifferentiated tumours (85%, 46/54), Borrmanns type 4 (90%, 9/10), tumours larger than 2.6 cm in diameter (65%, 53/81), tumours invading beyond the subserosa layer (78%, 46/59), and tumours with infiltrative growth (87%, 41/47). Furthermore, the frequency of Rd-type expression in cases with peritoneal dissemination (82%, 9/11) or lymph node metastasis (73%, 43/59) was significantly higher than that in cases without dissemination or metastasis. These results suggest that ECD might play a key role in the genesis of histological differentiation, and that the reduction of ECD expression may affect the mode of invasion and metastasis of human gastric cancer cells.

Prognostic significance of transforming growth factor-α in human esophageal carcinoma : implication for the autocrine proliferation

Background. The authors recently used immunostaining to demonstrate that patients with epidermal growth factor receptor (EGFR) overexpression have poor survival after surgery. However, the clinical significance of transforming growth factor (TGF)‐α, one of the ligands of EGFR, has not been demonstrated in esophageal carcinoma.

Prognostic value of dna ploidy in squamous cell carcinoma of esophagus. Analyzed with improved flow cytometric measurement

Background. The prognostic value of flow cytometric DNA analysis on paraffin‐embedded tumor samples has been controversial in esophageal cancer. To clarify its true significance, the authors developed an improved method that excludes the possibility of contamination by lymphocytes in tumor sample.

Immunohistochemical Evaluation of E-Cadherin and α-Catenin Expression in Human Esophageal Cancer

Tumor metastasis is initiated by disaggregation of invasive cells from the primary tumor - a step that requires a breakdown of intercellular adhesion. To investigate the mechanism of dysfunction in cell-cell adhesion of cancerous tissues, we evaluated E-cadherin (E-cad) and α-catenin (α-cat) expression of human esophageal cancer immunohistochemically. Eighty percent of the tumors showed reduced expression of both of the molecules. The frequency of α-cat negative tumors was observed in 47%, but none of them were E-cad negative. These results suggest that esophageal cancers lose α-cat expression more frequently than E-cad, and the loss of α-cat mights cause dysfunction of E-cad-mediated intercellular adhesion.

Immunohistochemical Evaluation of α-Catenin, Cadherin-Associated Intercellular Protein, Expression in Human Gastric Cancer

Immunohistochemical study of α-catenin, cadherin associated intercellular protein, was performed in 36 human gastric cancer tissues. All normal epithelium strongly expressed α-catenin as well as E- cadherin, while 67% of the tumor had reduced expression of α-catenin. Compared to E-cadherin expression, α-catenin expression was similar in 26 cases (72%), but weaker in 9 cases (25%). The reduction of α-catenin expression was associated with dedifferentiation, and infiltrative growth. These results indicated that the reduction of α-catenin expression may play a crucial role for cancer invasion through down-regulation of E-cadherin function.

Endoscopic Examination for the Early Esophageal Cancer in Patients with Head and Neck Cancers

Endoscopic screening of the esophagus with Lugol-dye staining was performed on 304 patients with head and neck cancers at the Department of Surgery II, Osaka University Medical School between June 1987 and August 1992. We found 19 patients with esophageal cancer (6.3%) and 21 patients with esophageal dysplasia (6.9%). Fifteen (78%) of 19 esophageal cancer patients were early stages (within submucosal invasion) with no lymph node metastases. Twelve (63%) of 19 esophageal cancer patients coexisted with multiple areas of dysplasia and/or cancer. The esophageal epithelium in patients with head and neck cancers may have tendency of field cancerization and multicentric potency for carcinogenesis.

Correlation Between Expression of E-Cadherin and Metastasis and Invasion in Human Esophageal Cancer

Cadherins are Ca2+-dependent cell-cell adhesion molecules which are possibly involved in the process of metastasis in cancer cells. We have investigated the expression of E-cadherin (E-CD), which is a subclass of cadherin expressed on cell membranes in normal esophageal epithelium. Sixty-two human esophageal cancers were studied with immunoblotting (5 cases) and immunohistochemical staining (62 cases) using monoclonal antibody for human E-CD (HECD-1) on frozen surgical specimens, and the correlation between E-CD expression and incidence of clinical lymph node metastasis and cancer invasion was investigated.