Unique properties of 189 amino acid isoform of vascular endothelial growth factor in tumorigenesis

The 189 amino acid isoform of vascular endothelial growth factor (VEGF189) has been shown to be more strongly associated with the cell membrane than other isoforms of human VEGF (VEGF121, VEGF165). To analyze the biological activities of these VEGF isoforms on tumor growth, we transfected human VEGF121, VEGF165 or VEGF189 cDNA into the human colon cancer cell line SW-480, and established several clones overexpressing these VEGF isoforms. The total amounts of VEGF protein in the culture supernatants of the VEGF189-transfectants were less than those of VEGF121 and VEGF165-transfectants. These transfectants showed no significant differences in growth in culture. Nevertheless, the rate of in vivo tumor growth of VEGF189-transfectants was faster than or equivalent to that of VEGF121-transfectants, while the VEGF165-transfectant showed the greatest enhancement of tumor growth. The protein levels of VEGF were markedly increased only in the VEGF189-transfectants cultured in the presence of heparin. The enhanced in vivo tumor growth of VEGF189-transfectants can be partly explained by the cell-associated features of VEGF189 molecules. The VEGF189 molecule, which is strongly bound to the cell surface, has unique properties and high potential in local angiogenesis and tumor growth in the cancer inductive microenvironment.

Neuropilin 1 and neuropilin 2 co-expression is significantly correlated with increased vascularity and poor prognosis in nonsmall cell lung carcinoma

BACKGROUND

Cell-retained isoforms of vascular endothelial growth factor A (VEGF-A) have been reported to play an essential role in tumor progression through stromal neovascularization in malignant solid tumors. While more than 95% of nonsmall cell lung carcinoma (NSCLC) expresses cell-retained VEGF-A isoform, the clinicopathologic implications of neuropilin (NRP), considered the specific receptor for limited types of VEGF-A isoform, are not well understood.

METHODS

The authors examined NRP1 and NRP2 mRNA expression in 68 NSCLCs and 15 extraneoplastic tissues by a densitometry-assisted, semi-quantitative reverse transcription-polymerase chain reaction. The authors determined the distinct expression of NRPs using the expression level of NRPs relative by optical density to beta2-microglobulin. The authors also investigated VEGF-A isoforms, their receptors, and the clinical implications. Vascularity of NSCLC was morphologically estimated on sections immunostained with anti-CD34 antibody.

RESULTS

Eleven of 15 extraneoplastic specimens showed NRP1 expression (73.3%) and 8 showed NRP2 expression (53.3%). The expression level of NRP1 or NRP2 of neoplasmic tissue was higher than that of extraneoplastic tissues (P < 0.01, Mann-Whitney U test). Fifty-five and 44 NSCLCs expressed NRP1 and NRP2, respectively. Forty patients co-expressing NRP1 and NRP2 showed significantly poorer prognosis and increased vessel counts as compared to those 28 cases without co-expression (P < 0.05, log-rank test; P < 0.05, Mann-Whitney U test).

CONCLUSIONS

The co-expression of NRP1 and NRP2 genes is significantly correlated with tumor progression through neovascularization in NSCLC. These results suggest that both NRP1 and NRP2 are key molecules for stromal vascularization by cell-retained VEGF in NSCLC.

Minute mixed ductal-endocrine carcinoma of the pancreas with predominant intraductal growth

We report a rare case of minute (5 mm x 4 mm) mixed ductal-endocrine carcinoma of the pancreas with predominant intraductal growth. A 34-year-old Japanese man was admitted because of elevated serum pancreatic enzymes. Endoscopic retrograde pancreatography revealed an unidentified material of 18 mm within the main pancreatic duct. Stone or parasite with acute pancreatitis was suspected clinically, and the biopsy revealed malignant cells positive for CA19-9, carcinoembryonic antigen (CEA) and synaptophysin. No apparent tumor was identified in the pancreas by various imaging techniques. Resection of pancreatic body and tail was performed. Grossly, the main pancreatic duct in the pancreatic body was occluded by as much as 20 mm. The pancreas had minute carcinoma of 5 mm x 4 mm just around the occluded main pancreatic duct. The tumor cells invaded the main pancreatic duct and spread within it as long as 20 mm. Histologically, the carcinoma had biphasic pattern; one was ductal carcinoma with tubular formations and another was carcinoma with neuroendocrine features. These two elements were admixed, and the ductal element comprised 30% while the endocrine element comprised 70%. The ductal element was immunoreactive for cytokeratins, CEA and CA19-9, while the endocrine element was immunoreactive for chromogranin A and synaptophysin. No immunoreactivity for pancreatic enzymes was noted. Ultrastructural observations showed dense core granules and no zymogen granules. Our case is unique clinically in that the tumor manifested as an intraductal material and no apparent tumor was found by imaging modalities, and pathologically in that the tumor was rare mixed ductal-endocrine carcinoma and the tumor was very small and mainly grew within the main pancreatic duct.

Interleukin 10 expression is correlated with thrombospondin expression and decreased vascular involvement in colon cancer

Interleukin 10 (IL-10) is an immuno-suppressive cytokine produced by T-lymphocytes, and a regulatory molecule for angiogenesis in various cancers. We examined IL-10 gene expression in 53 colon cancer patients who underwent surgical resection. IL-10 gene expression was correlated with TSP1 and TSP2 gene expression (P=0.0049, P=0.0285). Colon cancer with IL-10 gene expression (19/53) showed significantly decreased venous involvement (P=0.0433). The mean vessel counts in the colon cancers with IL-10 gene expression were significantly lower than those without IL-10 gene expression (P<0.001). These results suggested that IL-10 stimulates angiostatic factor gene expression, and results in suppression of venous involvement.

Gene expression of angiogenesis related factors in glioma

Angiogenesis plays an important role in growth and proliferation of cancer. Various angiogenic and angiostatic factors regulate angiogenesis. In this study, we examined gene expression of the angiopoietin family including angiopoietin 1 (Ang1) and angiopoietin 2 (Ang2) in 39 gliomas and 5 glioma-xenografts by RT-PCR. Ang1 and Ang2 genes were expressed in 54%, and 77% of gliomas, respectively. The expression of Ang1 was significantly correlated with the expression of Ang2. Both Ang1 and Ang2 were shown to be expressed in the glioma cells. Ang2 gene expression was correlated with VEGF gene expression. Angiopoietin molecules may synergistically cooperate in growth and vascularization in glioma.

Expression of cadherins and their undercoat proteins (alpha-, beta-, and gamma-catenins and p120) and accumulation of beta-catenin with no gene mutations in synovial sarcoma

E-cadherin, the major intercellular adhesion molecule of epithelial cells, is important in determining the architecture of sarcomas, especially those showing epithelioid features. In addition to its role in cell adhesion, beta-catenin, a cadherin undercoat protein, has been shown to function as a downstream transcriptional activator of the Wnt/Wingless signaling pathway. In order to evaluate the significance of the cadherin cell adhesion system and the Wnt/Wingless signaling pathway in the morphogenesis and/or tumorigenesis of synovial sarcoma (a major type of sarcoma with epithelioid features), immunoreactivity for pan-cadherin, E-cadherin, and their undercoat proteins (alpha-, beta-,and gamma-catenins and p120) was evaluated in 15 synovial sarcomas. Immunoreactivity for pan-cadherin, E-cadherin, alpha-catenin, beta-catenin, and p120 was observed in all 15 specimens. Immunoreactivity for pan-cadherin was stronger than that for E-cadherin. Expression of gamma-catenin was detected in ten specimens. Although beta-catenin was observed only at the cell-cell boundaries in four specimens, it was present in the nucleus and cytoplasm and at the cell-cell boundaries in the other 11, suggesting constitutional activation of the Wnt/Wingless signaling pathway in synovial sarcoma. Direct sequencing for exon 3 of the beta-catenin gene, however, revealed no mutations in any of the 15 specimens. In conclusion, other types of cadherin besides E-cadherin, together with cadherin undercoat proteins, may play a role in cell adhesion in synovial sarcoma. Furthermore, mechanisms other than mutation of exon 3 of the beta-catenin gene may activate the Wnt/Wingless signaling pathway in this type of tumor.

Is it permissible to omit mediastinal dissection for peripheral non-small-cell lung cancers with tumor diameters less than 1.5 cm?

BACKGROUND

Recently the pros and cons of limited surgery for small-sized peripheral non-small-cell lung cancers (PNSCLCs), such as omission of mediastinal dissection, etc., have been vigorously debated. We analyzed whether hilar/mediastinal lymph node metastases were present in 30 small-sized PNSCLCs.

MATERIAL AND METHODS

In the nine years from 1990 to 1998, 294 lung cancer patients underwent lobectomy or pneumonectomy combined with hilar/mediastinal dissection in the Tokai University Hospital. Thirty of these patients diagnosed as having cT1N0M0 PNSCLC with tumor diameters of 1.5 cm or less by computed tomography, are evaluated in this article.

RESULTS

The 30 PNSCLC patients consisted of 14 males and 16 females with a mean age of 61 +/- 9 years. Twenty six patients (87%) had no hilar nor mediastinal lymph node metastases (pN0), one patient (3%) had a hilar lymph node metastasis (pN1), and three patients (10%) had mediastinal lymph node metastases (pN2).

CONCLUSIONS

Mediastinal lymph node metastases were histologically observed in 3 (10%) of 30 PNSCLC patients with tumor diameters of 1.5 cm or less. Our results show that mediastinal dissection is still necessary even for small-sized lung cancers.

Parvovirus B19 infection induces apoptosis of erythroid cells in vitro and in vivo

OBJECTIVE

intrauterine parvovirus B19 infection is related to non-immune hydrops fetalis, the pathogenesis of which is based on the strict tropism of B19 for erythroid precursor cells and the massive destruction of the infected erythroid cells, although the mechanism of beta19-induced cytotoxicity has not been studied in detail. The purpose of this study is to provide empirical evidence that beta19 induces apoptosis of erythroid cells both in vitro and ill vivo.

METHODS

we analysed culture cells infected in vitro by B19 and tissues of nine cases of hydrops fetalis caused by B19 intrauterine infection by histological and biological methods.

RESULTS

cells infected iil vitro by B19 showed nuclear changes characteristic of apoptosis by light microscopic examination and DNA extracted from the infected cells was fragmented. Electron microscopic examination showed the nuclei of infected cells contained crescent-shaped clumps of heterochromatin with increased density and double staining with anti-B1 9 antibody and terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate-digoxigenin nick-end labeling (TUNEL) confirmed apoptosis of individual cells. Tissues of cases of hydrops fetalis caused by B19 contained erythroid cells with nuclear inclusions and characteristic nuclear changes of apoptosis by light microscopy. The double-staining confirmed apoptosis of erythroid cells in the tissues. Immunohistochemical analysis with antibodies against cellular factors involved in apoptosis showed that caspase3, p53 and p21 were positive in infected cells.

Small mucosal carcinoma of the stomach with para-aortic lymph node metastasis: a case report and review of the literature

A 38-year-old woman presented with a mucosal gastric carcinoma measuring 0.7 x 0.5 cm and para-aortic lymph node metastasis. Radiographic and endoscopic studies showed a small depressed lesion on the anterior border of the gastric angle, which was classified as a type II c + III lesion. Histological examination of the biopsy specimen revealed a signet-ring cell carcinoma. Distal gastrectomy with wide lymph node excision was performed. Detailed study of the resected specimen revealed that the tumour was limited to the mucosa, but metastasized to both the perigastric and para-aortic lymph nodes. The patient received adjuvant immunochemotherapy postoperatively. However, multiple bone metastases developed at 3 years and she died 4 years after the operation.

The role of histamine in ethanol-induced gastric mucosal injury in the rat

It has been suggested that changes in the micro circulatory system are related to the early production of acute gastric mucosal injury and inflammatory factors such as prostaglandins, histamine, etc., have been considered as contributing to the development of the injury. We assessed the permeability of the gastric mucosa in rats with ethanol-induced acute mucosal injury by measuring the leakage rate of 51chronium-ethylene-diamine-tetraacetic acid (51Cr-EDTA) into the gastric juice. Histamine concentrations in the gastric mucosa was measured by high performance liquid chromatography. The enterochromaffin-like (ECL) cell counts in the gastric mucosa was performed following histamine staining with an enzyme-labeled antibody, and the histamine released due to degranulation was observed. We also investigated the kinetics of endogenous histamine in the gastric mucosa. Five minutes after the administration of ethanol, an increase in permeability, an increase in histamine concentration, and a decrease in ECL cell count were found in the gastric mucosa. These results suggest that endogenous histamine in the gastric mucosa is closely related to the early development of acute gastric mucosal injury.

Endoscopic screening for esophageal cancer in 788 patients with head and neck cancers

Esophageal cancer has a poor prognosis because it is difficult to detect in its early stages and, even if an operation is possible, the postoperative quality of life is much impaired. An early diagnosis can lead to a good prognosis and enables treatment by endoscopic mucosal resection (EEMR), contributing to a postoperative good quality of life. As head and neck cancers are known to have a high risk of concomitant esophageal cancer, endoscopic screening with iodine staining was performed on 788 patients with head and neck cancers. Among them, 93 cases of esophageal cancers (11.8%) and 23 cases of gastric cancers (2.9%) were detected. Seventy-two cases (77.4%) of the 93 esophageal cancers were superficial cancers limited to the submucosal layer. Twenty cases, treated by EEMR, had a good postoperative course without local recurrence. We suggest that endoscopic screening for esophageal cancer should be performed on all patients with head and neck cancers, because it allows early detection and a good prognosis, and the treatment can be completed by endoscopic maneuver.

Myofibroblastoma of the breast: report of a case

We report herein the case of a 36-year-old woman in whom a breast mass was diagnosed histologically and immunohistochemically as myofibroblastoma (MFB). The patient initially presented with a breast mass measuring 1.0 x 1.5 cm which was demonstrated by mammography as a well-circumscribed, round tumor with two coarse calcifications. On ultrasonography, the tumor showed slight shadowy internal echoes. Histological examination of an excisional biopsy specimen demonstrated a tumor consisting of spindle-shaped cells and broad bands of hyalinized collagen with cartilaginous and osseous components, but no epithelial components were observed. Immunohistochemically, the tumor cells were diffusely positive for alpha smooth muscle actin, and a diagnosis of MFB was made. A wide excision of the breast was performed as a secondary procedure, and the patient is well and free from recurrence 1 year after her operation. We present this case to stress the need for breast surgeons to be aware of the existence of MFB when considering the differential diagnosis of stromal lesions of the breast to avoid performing unnecessarily extensive procedures.

A case of pituitary somatotroph adenoma with concomitant secretion of growth hormone, prolactin, and adrenocorticotropic hormone--an adenoma derived from primordial stem cell, studied by immunohistochemistry, in situ hybridization, and cell culture

Somatotroph adenomas often secrete prolactin (PRL) besides growth hormone (GH) and are sometimes immunostained for other anterior pituitary hormones or their subunits, such as thyroid-stimulating hormone (TSH) beta-subunit and glycoprotein hormone alpha-subunit (alpha SU). However, somatotroph adenomas showing hypersecretion of adrenocorticotropic hormone (ACTH) are extremely rare. There have been, to our knowledge, only five published reports on somatotroph adenomas accompanied by excessive ACTH secretion. Here we report a case of intracavernously invading somatotroph macro-adenoma with high serum GH, PRL, and ACTH levels. We examined the case using immunohistochemistry (IHC), in situ hybridization (ISH), and cell culture, and confirmed GH, PRL, and ACTH, as well as alpha SU, production, and the expression of Pit-1 protein by the adenoma, which is known as a transcriptional factor for GH, PRL, and TSH, not for ACTH. Therefore, the presence of unknown transcriptional factor other than Pit-1, common to GH, PRL, and ACTH, may be speculated to be expressed in this adenoma. In our previous study, we had found plurihormonal mRNA expression, especially for ACTH, the beta-subunit of follicle-stimulating hormone and luteinizing hormone in some somatotroph adenomas, using non-radio-isotopic ISH, and suggested that these adenomas might be derived from plurihormonal primordial stem cells. Our present case is significant from the viewpoint of histogenesis of pituitary adenomas, because it further supports the cell origin of somatotroph adenomas from plurihormonal primordial stem cells, and moreover it suggests the presence of unknown transcriptional factor other than Pit-1, common to GH, PRL, and ACTH.