Two human epithelial cell lines, trophoblastic teratocarcinoma HT-H and endometrial adenocarcinoma SNG-M cells, adhere to each other at their respective apical cell surfaces in a divalent cation-independent manner. Two novel molecules responsible for the adhesion between these two cell types were identified by expression cDNA cloning. One, named trophinin, is an intrinsic membrane protein and mediates homophilic self-binding. Another, named tastin, is a cytoplasmic protein and is necessary for trophinin to function as a cell adhesion molecule. Trophinin and tastin appear to be associated with the cytoskeleton in HT-H and SNG-M cells. These molecules are normally not expressed in various types of human cells in tissues, with the exception of macrophages. Strong expression of these molecules was detected in the trophectoderm surface of monkey blastocyst. These molecules are also expressed in human endometrial surface epithelium on day 16/17 at the early secretory phase of human endometrium, the time consistent with that expected for the "implantation window."
Purpose: Clear cell carcinoma (CCC) is a rare histologic subtype that demonstrates poor outcomes in epithelial ovarian cancer. The Japanese Gynecologic Oncology Group conducted the first randomized phase III, CCC-specific clinical trial that compared irinotecan and cisplatin (CPT-P) with paclitaxel plus carboplatin (TC) in patients with CCC. Patients and Methods: Six hundred sixty-seven patients with stage I to IV CCC of the ovary were randomly assigned to receive irinotecan 60 mg/m2 on days 1, 8, and 15 plus cisplatin 60 mg/m2 on day 1 (CPT-P group) every 4 weeks for six cycles or paclitaxel 175 mg/m2 plus carboplatin area under the curve 6.0 mg/mL/min on day 1 every 3 weeks for six cycles (TC group). The primary end point was progression-free survival. Secondary end points were overall survival, overall response rate, and adverse events. Results: Six hundred nineteen patients were clinically and pathologically eligible for evaluation. With a median follow-up of 44.3 months, 2-year progression-free survival rates were 73.0% in the CPT-P group and 77.6% in TC group (hazard ratio, 1.17; 95% CI, 0.87 to 1.58; P = .85). Two-year overall survival rates were 85.5% with CPT-P and 87.4% with TC (hazard ratio, 1.13; 95% CI, 0.80 to 1.61; one-sided P = .76). Grade 3/4 anorexia, diarrhea, nausea, vomiting, and febrile neutropenia occurred more frequently with CPT-P, whereas grade 3/4 leukopenia, neutropenia, thrombocytopenia, peripheral sensory neuropathy, and joint pain occurred more frequently with TC. Conclusion: No significant survival benefit was found for CPT-P. Both regimens were well tolerated, but the toxicity profiles differed significantly. Treatment with existing anticancer agents has limitations to improving the prognosis of CCC.