Epidermal cell membrane as the origin of pemphigus antigen.

The substance bound to the pemphigus antibody (P-Ab), pemphigus antigen, was removed from the surface of the keratinocytes of both human and guinea pigs with high concentrations of trypsin. When keratinocytes were cultured for more than 24 hours, the antigen reappeared on the surface. Furthermore, P-Ab was recovered from the P-Ab treated cultured cells by acid treatment. Cell membranes were prepared from human keratinocytes in order to determine whether or not the antigen was situated on their surface. The antigen was also detected on the surface of the cell membrane. As the membrane was found to be able to absorb P-Ab, the antigen was extracted from the membrane by papain digestion and P-Ab coated Sepharose column chromatography. The eluate from the column was also able to block P-Ab activity. At the same time, the culture supernatant of both human and guinea pig keratinocytes was examined for its ability to block P-Ab activity. The culture supernatant showed a slight ability to block P-Ab. The origin and nature of the antigen was discussed.     

A case of recurrent esophageal cancer successfully treated with weekly paclitaxel in combination with radiotherapy

A 48-year-old man underwent subtotal esophagectomy for pStage III (pT 3 pN 3) thoracic esophageal carcinoma on June 20, 2002, in combination with chemotherapy (5-FU 500 mg/day day 1-14, CDDP 10 mg/day day 1-14, VDS 3 mg on days 1 and 8) before and after the operation. Recurrence was seen 7 months after the operation in right pleura and lower mediastinum. Chemo (same regimen)-radiotherapy (50 Gy) was then performed but without effect. Thereafter, lung and upper mediastinal metastases were found, and weekly administration of paclitaxel (70 mg/m2, day 1, 8, 15, q 4w) was initiated in combination with radiotherapy (40 Gy). Two cycles of treatment resulted in PR, and CR was achieved after the 8th cycle was completed. Although treatment was terminated after the 12 th cycle due to development of peripheral neuropathy (grade 2), CR was still maintained 8 months after the completion of treatment. These results suggested the effectiveness of the treatment in cases that show resistance to conventional 5-FU-based chemotherapy.     

Regulation of aminopeptidase A expression in cervical carcinoma: role of tumor-stromal interaction and vascular endothelial growth factor

We previously demonstrated that aminopeptidase A (APA), a membrane-bound metallopeptidase degrading bioactive peptides such as angiotensin II (Ang II), is expressed in neoplastic lesions of the uterine cervix, and that its expression is upregulated as the lesion progresses from cervical intraepithelial neoplasms (CIN) toward invasive squamous cell carcinomas (SCC). The present study investigated the regulatory mechanisms involved in APA expression and its potential role in cervical carcinoma. Immunohistochemical staining in high-grade CIN and SCC tissues showed that APA was strongly expressed at the edge of lesions adjacent to cervical stromal cells. Fluorescence-activated cell sorting analysis demonstrated that cell surface APA expression was extremely low in three human SCC cell lines, SiHa, TCS and CaSki, under basal conditions. However, both contact and noncontact cocultures with human cervical fibroblasts resulted in the induction of APA expression in these SCC cells. APA expression was also induced in vivo when TCS cells were subcutaneously inoculated into nude mice. Furthermore, APA expression and enzymatic activity were enhanced by addition of the conditioned medium (CM) from fibroblast culture, but not by heat-treated CM. Among the various cytokines tested, vascular endothelial growth factor (VEGF) significantly increased APA activity, and induction of APA by the fibroblast CM was partly inhibited by anti-VEGF neutralizing antibody. Finally, APA cDNA-transfected APA-overexpressing TCS cells significantly reduced the Ang II-induced cell invasion ability as compared with parental or control vector-transfected TCS cells, although there was no significant difference in cellular proliferation among them. These results suggested the importance of tumor-stromal interaction for the regulation of APA expression in the microenvironment of cervical carcinoma and the potential role for this peptidase in regulating tumor invasion through inactivation of Ang II activity.     

Activation of invasiveness of cervical carcinoma cells by angiotensin II

OBJECTIVE: Angiotensin II recently has been reported to promote the growth of several kinds of cells. In this study, we investigated the effect of angiotensin II on cervical carcinoma cells. STUDY DESIGN: The expression of angiotensin II type I receptor was examined by immunohistochemistry in normal and neoplastic cervical tissues. Invasion assay was examined in Siha cells (cervical squamous cell carcinoma) and vascular endothelial growth factor levels were assayed with a vascular endothelial growth factor enzyme-linked immunosorbent assay kit. RESULTS: Mean staining intensity level was stronger in invasive carcinoma cells than in normal, dysplasia, and carcinoma in situ tissues. Angiotensin II induced the secretion of vascular endothelial growth factor from Siha cells. Furthermore, angiotensin II promoted the invasive potential of Siha cells. These effects were reversed by the addition of anti-human vascular endothelial growth factor antibody and candesartan (antagonist of angiotensin II type I receptor). CONCLUSION: Angiotensin II is involved in the progression of cervical carcinoma, because it induces the secretion of vascular endothelial growth factor through angiotensin II type I receptor, which results in the increased invasiveness of carcinoma cells.     

Stenting in obstruction of superior vena cava; clinical experience with the self-expanding endovascular prosthesis

From August 1997 to December 2002, 14 consecutive patients with superior vena cava syndrome with the self-expanding endovascular prosthesis. Diagnoses were adenocarcinoma in 6, small cell carcinoma in 4, squamous cell carcinoma in 1, metastatic lung cancer in 2, and invasive thymoma in 1. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were measured on their admission and perioperative period. Expecting only 1 patient complete symptomatically relieved within 3 days of stent implantation. Superior vena cava pressure or radial pressure of the stent was sufficient to relieve obstruction. Preoperative ANP level were normal, BNP level were increased. Postoperatively both ANP level and BNP level were slightly increased under intravenous dopamine hydrochloride. Implantation of the self-expanding stent endovascular prosthesis for superior vena cava syndrome provides rapid symptomatic relief and improves the patient's quality of life.     

Suppression of invasion and peritoneal carcinomatosis of ovarian cancer cells by overexpression of AP-2alpha

A previous report demonstrated that AP-2alpha favors the survival of ovarian cancer patients by clinical findings. However, the functional roles of AP-2alpha in human ovarian cancers have not been determined. To clarify the roles, we overexpressed AP-2alpha in SKOV3 human ovarian cancer cells, which originally possess little AP-2alpha. AP-2alpha overexpression changed cell morphology from spindle to epithelioid type and suppressed cell proliferation and invasion, which would be partially correlated with decreased phosphorylation levels of the erbB2, Akt and ERK pathways, increased E-cadherin and reduced pro-matrix metalloproteinase-2 levels. Moreover, nude mice intraperitoneally injected with AP-2alpha-overexpressing cells survived longer than those with neo-transfected cells. The present data represent the first direct evidence that AP-2alpha plays a tumor suppressive role in ovarian cancer.     

Oncolytic viral therapy for human ovarian cancer using a novel replication-competent herpes simplex virus type I mutant in a mouse model

OBJECTIVE: Attenuated mutant strains of herpes simplex virus (HSV) have been effectively used for treatment of malignant brain tumors. As HSV-1 can infect and lyse a variety of cell types, other malignancies may also benefit from such treatment. We sought to test the feasibility of HSV-1 mutant-mediated gene therapy treatment of ovarian cancer. METHODS: We prepared two attenuated mutant HSV-1 strains. An HSV-1 mutant, hrR3, has replaced the gene encoding ribonucleotide reductase (RR) with the lacZ reporter gene. We also developed a new replication-competent HSV-1 mutant, HR522; this virus, expressing the lacZ reporter gene, induces syncytium formation in infected cells. We compared the efficacy of HR522 with, paclitaxel (Taxol) and hrR3 in the treatment of nude mice harboring human ovarian cancer cells. We also examined the effect of the prodrug ganciclovir (GCV) on the treatment mediated by these HSVs. Survival was evaluated by Kaplan-Meier method and log-rank test. RESULTS: The survival of mice treated with a high-titer hrR3 (5 x 10(7) plaque-forming units [PFU]) was significantly prolonged as compared with the group given paclitaxel (P < 0.0001, log-rank test). Although the survival of mice treated with high-titer HR522 (5 x 10(7) PFU) was not significantly prolonged compared with paclitaxel-treated group (P = 0.212, log-rank test), GCV markedly enhanced the efficacy of HR522 administration (P < 0.005, vs paclitaxel, log-rank test). The lacZ gene product, visualized using 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) histochemistry, was detected in HR522-treated tumors in areas also exhibiting apoptotic changes. CONCLUSIONS: These findings indicate that the combination of HR522 and GCV possesses significant therapeutic potential for treatment of ovarian cancer. Such viral therapy offers a novel approach to reductions in the dissemination of ovarian cancer.