Pleomorphic lobular carcinoma of the breast: a comparison of cytopathological features with other lobular carcinoma variants.

OBJECTIVE: Pleomorphic lobular carcinoma (PLC) is a subtype of breast cancer with unique morphological features, but it remains controversial whether PLC should be considered an independent disease entity. The aim of this study was to illustrate cytopathological characteristics of PLC in comparison with other lobular carcinoma variants. METHODS: We investigated clinicopathological features of PLC (n = 11) compared with those of other variants of invasive lobular carcinoma (ILC, non-PLC) (n = 32). Histological variants of the non-PLC group consisted of classic (n = 25), solid (n = 2), alveolar (n = 1) and a tubulolobular type (n = 4). A review of cytological reports and fine needle aspiration (FNA) smear samples was performed for the PLC (n = 9) and non-PLC (n = 27) groups. RESULTS: Patients with PLC were older, and had a higher nuclear grade and a higher incidence of axillary lymph node metastasis and triple negative phenotype than non-PLC patients (P = 0.007, P < 0.001, P = 0.02 and P < 0.001, respectively). Cytological findings in PLC included medium- to large-sized nuclei, prominent nucleoli, a moderate-to-severe degree of pleomorphism, apocrine change and background necrosis, none of which were evident in the smears of the non-PLC group (P < 0.001, P = 0.002, P < 0.001, P < 0.001, and P = 0.03, respectively). Despite these differences, patients with PLC and non-PLC showed similar clinical outcomes in our follow-up period. CONCLUSIONS: Based on our results, a cytological diagnosis of PLC should be proposed if there are moderate- to large-sized nuclei, prominent nucleoli, a moderate-to severe degree of nuclear pleomorphism, apocrine change and necrosis in the background in FNA biopsy samples.

Mucinous carcinoma of the breast: a comparative study on cytohistological findings associated with neuroendocrine differentiation.

OBJECTIVE: Mucinous carcinoma (MCA) may show neuroendocrine differentiation (ND), but the cytological features characteristic of ND remains elusive. We compared fine needle aspiration (FNA) findings of MCA between cases with high and low degrees of ND. METHODS: Histological sections of 37 MCA cases were immunohistochemically evaluated for expression of chromogranin A and synaptophysin, and were graded as 0 to 3+ degrees of ND. They were divided into low ND (grade 0 and 1+) and high ND (grade 2+ and 3+) groups. Pre-operative FNA samples of each group were assessed for cytological features. RESULTS: The mean age of the high ND group (n = 18) was higher than the low ND group (n = 19, P = 0.01). In FNA samples of the high ND group, 17 cases showed moderate to severe degrees of discohesiveness, but low ND cases mainly showed no or only mild discohesiveness (P < 0.001). Nine of the low ND cases displayed overlapped, cohesive cell clusters, whereas, in the high ND cases, the cells were arranged in a loose, flat and monolayered pattern (P = 0.045). Fourteen of the high ND cases had round nuclei, but oval nuclei were predominant in the low ND cases (P = 0.027). The nuclei were eccentrically located in 12 of the high ND cases but were centrally located in 14 of the low ND cases (P = 0.01). CONCLUSIONS: Mucinous carcinoma with high ND may be diagnosed by the presence of discohesiveness, a flat, monolayered pattern, and round or eccentrically located nuclei. Features of ND in carcinomas in other organs, such as intracytoplasmic granules and coarse chromatin, may not be reliable cytological features of ND in MCA.

Cellular sources of tenascin-C in canine mammary carcinomas.

Tenascin-C (Tn-C) is an extracellular matrix glycoprotein implicated in the progression of several human cancers. In canine mammary carcinomas, accumulation of Tn-C has been recognized in 3 different areas: regions of proliferating myoepithelial cells in complex carcinoma, basement membrane zone in low-grade simple carcinoma, and reactive stroma in high-grade simple carcinoma. To identify the Tn-C synthesizing cells in these areas, we utilized double-labeling immunohistochemistry, branched DNA in situ hybridization, and in situ hybridization-immunohistochemistry double-labeling techniques. In complex carcinomas, Tn-C was generated by proliferating myoepithelial cells. Tn-C in low-grade simple carcinomas was also derived from myoepithelial cells existing as a basal monolayer. However, stromal Tn-C in high-grade carcinomas was mainly synthesized by fibroblasts/myofibroblasts, similar to human breast cancer. Thus, the origin of Tn-C in canine mammary carcinomas differs between low- and high-grade malignancies. The role of myoepithelial cell-generated Tn-C is not yet understood.

A non-acromegalic case of multiple endocrine neoplasia type 1 accompanied by a growth hormone-releasing hormone-producing pancreatic tumor.

Cases of acromegaly due to GHRHproducing pancreatic endocrine tumors have been reported. Here we present a case of a 31-yr-old nonacromegalic man with hyperparathyroidism and elevated serum IGF-I with normal serum GH levels. Serum GH was not suppressed below 1 ng/ml by the glucose tolerance test and increased in response to TR H and GHRH administration. Magnetic resonance imaging (MRI) revealed pituitary hyperplasia and an abdominal computed tomography (CT ) scan showed a tumor in the pancreatic tail. Plasma concentration of GHRH was elevated. Based on these clinical data, multiple endocrine neoplasia (MEN) type 1 was suspected. Three enlarged parathyroid glands were removed and a distal pancreatectomy was performed. Pathological examination of the parathyroid glands and pancreatic tumor showed nodular hyperplasia and a well-differentiated endocrine tumor, respectively, both compatible with MEN features. Immunohistochemistry revealed positive immunoreactivity for GHRH, SS , insulin, glucagon, chromogranin A, and pancreatic polypeptide in the pancreatic tumor. After pancreatic surgery, elevated levels of GHRH and IGF-I were normalized and pituitary hyperplasia definitely decreased in size. In cases of pituitary hyperplasia with elevated IGF-I, ectopic GHRH syndrome must be considered even if physical features of acromegaly are absent. It is also important to measure plasma GHRH concentrations in order to give a diagnosis.

Expression of nestin in rat and human glomerular podocytes.

Nestin is a neuroepithelial precursor cell marker expressed in a variety of human cell types during development. However, no information exists on the expression of nestin in mature glomeruli as well as during the glomerular development. Here, we examined nestin expression in rat and human glomerular tissues in quiescent states using RT-PCR and immunohistochemical methods. Nestin mRNA was detected in the rat glomeruli in parallel with its expression in developing rat brains. In the normal mature rat glomeruli, WT-1 positive cells expressed nestin. Co-expression of nestin and vimentin was observed in mature rat podocytes. Immunoelectron microscopy revealed nestin localization in the cell bodies and primary processes of podocytes. A similar expression pattern was observed for vimentin. In matured glomeruli, nestin was not expressed by mesangial and endothelial cells. In the newborn rat, early developing glomeruli (metanephric cap, metanephric vesicle, comma-shaped vesicle and S-shaped body phases) expressed nestin. In the capillary loop stage, Bowman's capsules also expressed nestin. Immunoelectron microscopy demonstrated that developing podocytes and endothelial cells in S-shaped phase glomeruli expressed nestin. Additionally, in immature glomeruli, the mesangial cells in capillary stage of glomerulus also expressed nexin. As in the rat, WT-1 positive cells in human glomeruli also expressed nestin and immunoelectron microscopy confirmed nestin expression in human glomerular podocytes. These results reveal that in normal condition nestin is expressed in several glomerular cell types at early stage of development and becomes confined to podocytes in mature glomeruli, thus implicating nestin in podocyte functions.

Establishment and characterization of SV40 T-antigen immortalized human esophageal epithelial cells.

Normal human esophageal autopsy tissue was explanted in serum-free medium. The epithelial outgrowths were subcultured and then transfected by strontium phosphate coprecipitation with plasmid pRSV-T consisting of the RSV-LTR promoter and the sequence encoding the simian virus 40 large T-antigen. The transfected cells, but not the sham-transfected controls, formed multilayered colonies within 3-4 weeks, after which the colonies were transferred and cell strains (HE-451 and HE-457) developed. Both cell strains grew exponentially for 8-10 weeks and then senesced. After a "crisis" of 6-8 months, growth resumed in isolated colonies. One line, HET-1A from HE-457, was developed and has now undergone more than 250 population doublings. This line has retained epithelial morphology, stains positively for cytokeratins and the simian virus 40 T-antigen gene by immunofluorescence, and has remained nontumorigenic in athymic, nude mice for more than 12 months. Karyotypic analysis by Giemsa banding has shown that HET-1A is hypodiploid (34-40 chromosomes). Growth factor studies have shown that HET-1A is stimulated by Ca2+, and inhibited by fetal bovine serum, transforming growth factor-beta 1, and transforming growth factor-beta 2. This serum-free immortalized esophageal cell system will be useful for investigating the action of putative esophageal carcinogens.

Role of the adrenal renin-angiotensin system on adrenocorticotropic hormone- and potassium-stimulated aldosterone production by rat adrenal glomerulosa cells in monolayer culture.

The rat zona glomerulosa has a renin-angiotensin system that appears to function as an autocrine or paracrine system in the regulation of aldosterone production. To further investigate dynamic changes of production of renin and aldosterone in vitro we developed a primary monolayer culture of rat adrenal glomerulosa cells in serum-free medium. Collagenase-dispersed glomerulosa cells were incubated in PFMR-4 medium containing 10% fetal calf serum for 48 hours; the medium was then replaced with serum-free PFMR-4 medium. The cell viability and the aldosterone secretion were stable over the additional 48 hours in the serum-free control medium. After incubation for 24 hours in the serum-free medium, the cells were exposed to high K+ or adrenocorticotropic hormone (ACTH) for another 24 hours. ACTH stimulated aldosterone secretion, and this increased secretion was associated with an increase in renin activity (cell active renin, from 15.56 +/- 0.71 to 45.75 +/- 5.69; cell inactive renin, from 0.67 +/- 0.54 to 8.75 +/- 3.40; medium inactive renin, from 5.58 +/- 1.16 to 106.20 +/- 14.01 pg angiotensin I (Ang I)/micrograms protein/3 hr). Aldosterone was also stimulated by high K+. This increase was also associated with an increase in active renin in the cells (from 15.08 +/- 1.80 to 23.26 +/- 2.15 pg Ang I/micrograms protein/3 hr) and an increase in inactive renin in the medium (from 10.87 +/- 1.62 to 21.37 +/- 3.20 pg Ang I/micrograms protein/3 hr). Addition of the angiotensin converting enzyme inhibitor lisinopril attenuated both ACTH- and high K(+)-stimulated aldosterone secretion significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of hsp90 and cyclin D1 in human breast cancer.

The integral roles of heat shock proteins (hsps) in the cell cycle and in multistep processes leading to tumorigenesis have been implied. We examined the expression of hsp90alpha, hsp90beta and cyclin D1 in human breast cancer. Levels of mRNAs coding for hsp90alpha and cyclin D1 were significantly higher in cancer tissues than in non-cancer tissues. Moreover, there was a close relationship between the extent of the two mRNA levels, suggesting that increased expression of hsp90alpha, an isoform of the hsp90 family, is associated with the proliferation of human breast cancer. Hsp90beta was expressed in cancer cells, but not associated with cell proliferation.

Sex differences in mucosal response to Helicobacter pylori infection in the stomach and variations in interleukin-8, COX-2 and trefoil factor family 1 gene expression.

BACKGROUND: Gastric cancer incidence in men is almost double that in women. We investigated mucosal responses in the stomach against Helicobacter pylori (H. pylori) infections to elucidate the interindividual or sex-related differences, which may in turn be associated with gastric cancer incidence, mucosal changes of stomach as measured by the Sydney System, and interleukin-8, cyclooxygenase-2 and trefoil factor family 1 (TFF1) gene expression. METHODS: An age-, sex-, H. pylori status- and disease-matched case-control study was performed in 574 H. pylori-positive and 225 H. pylori-negative patients selected from 4125 patients with a diagnosis of benign disease of the stomach. Levels of acute and chronic inflammations, atrophy and intestinal metaplasia scored according to the Sydney System were compared by stomach site and by sex. Two biopsy specimens (antral and corpus gastric mucosa) from patients with benign gastric diseases (142 patients; 72 men, 70 women) were analysed for interleukin-8, cyclooxygenase-2 and TFF1 mRNA expression as measured by real-time PCR. RESULTS: Inflammation and activity scores in antrum with H. pylori infection were higher in men, but scores declined according to age. Atrophy and intestinal metaplasia scores in corpus with H. pylori infection appeared more severe in men than in women, especially in older patients. In women, atrophy score increased with increasing age, particularly in postmenopausal H. pylori-negative patients. Interleukin-8 mRNA induction was detected in both antrum and corpus mucosa in H. pylori infection, but sex differences were not found. Response of cyclooxygenase-2 mRNA expression against H. pylori infection in the mucosa was higher in men than women. In H. pylori-negative patients, TFF1 mRNA levels in women were significantly higher than in men, and TFF1 mRNA was significantly lower in positive than negative women. CONCLUSIONS: Sex differences in mucosal responses to H. pylori infection in the stomach may be correlated with sex differences in the incidence of stomach cancer.

Immunohistochemical and morphometric evaluations of coronary atherosclerotic plaques associated with myocardial infarction and diabetes mellitus.

Immunohistochemical and morphometrical studies were performed to elucidate the specificity of atherosclerosis in the descending branch (the segments 5 and 6) of the left coronary artery associated with acute myocardial infarction (AMI) in the anterior wall of the heart and non-insulin-dependent diabetes mellitus (NIDDM). The NIDDM without AMI group showed diffuse intimal thickening with smooth muscle cells, combined with much more intense immunostaining of tenascin than the non diabetic groups. The AMI without NIDDM group showed atheromatous thickening with decreased smooth muscle cells, a large number of macrophage and TUNEL-positive cells compared with the groups without AMI. However, the AMI with NIDDM group revealed atherosclerotic lesion with decreased smooth muscle cells, increased macrophages and TUNEL positive cells associated with the increased localization of tenascin and TGF-beta1 compared with the control. These findings suggest that the specificity of coronary atherosclerosis in diabetic patients may be the extensive atherosclerotic changes associated with increased tenascin. In AMI with NIDDM, increased TGF beta1 may induce apoptosis in the atheroma and coronary dysfunction, contributing to the development of acute myocardial infarction.

Melanotic neuroectodermal tumor of infancy in the skull associated with high serum levels of catecholamine. Case report.

The case of a 5-month-old boy with a left retromastoid melanotic neuroectodermal tumor of infancy is presented. The tumor extended from the subcutaneous tissue of the occiput to the cerebellar hemisphere. Histologically, the epidural part of the tumor was composed of undifferentiated neuroblasts, dense connective tissue, and glandular structures lined by melanin-containing cuboidal cells, whereas the subdural part contained differentiated neuroblasts and melanin-containing cells. The preoperative high serum levels of adrenaline, noradrenaline, vanillylmandelic acid, and neuron-specific enolase returned to normal after two operations and two cycles of chemotherapy; however, the dopamine level was mildly elevated. These data and immunohistochemical and ultrastructural findings strongly suggest that melanotic neuroectodermal tumor of infancy is derived from the neural crest.

Effect of general anesthesia on the abnormal immune response in patients with rheumatoid arthritis.

OBJECTIVE: To evaluate the influence of mental stress on the neuroendocrine-immune system in patients with rheumatoid arthritis (RA). METHODS: Twenty-four patients with RA and 10 patients with osteoarthritis (OA) who underwent total knee or hip arthroplasty under general anesthesia were enrolled in this study. The blood levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1Ra), tumor necrosis factor-alpha (TNF-alpha), soluble TNF receptors (TNF-Rs) and other substances related to stress were measured just before administering anesthesia on the day of the operation when the patients lay on the operating table and roughly 30 min later when the patients were under general anesthesia without mental stress. These values were compared with those at the same time on the day before the operation, which were considered as controls. RESULTS: In patients with RA under general anesthesia, the levels of IL-6, TNF-alpha, and TNF-R1 and TNF-R2 in the peripheral blood were significantly decreased compared with the levels before anesthesia (p < 0.01). Before anesthesia the levels of IL-1Ra in the peripheral blood were significantly higher, and the level of IL-1Ra was enhanced after the administration of general anesthesia, when compared with the level on the day before the operation (p < 0.01). Such changes were not apparent in patients with OA. CONCLUSION: In patients with RA, excessive mental stress should be eliminated to modify the interaction between the stress-immune system and stress-endocrine system as a method to better control disease activity.

Immunohistochemical expression of T, Tn and sialyl-Tn antigens and clinical outcome in human breast carcinoma.

BACKGROUND: The extent of expression of reactive T (Thomsen-Friedenreich), Tn and sialyl-Tn antigens has been assumed to predict carcinoma aggressiveness. We studied the expression of T, Tn and sialyl-Tn antigens in a relatively large cohort of breast carcinoma patients with known long-term outcome to assess the clinical and biological significance of these antigens. MATERIALS AND METHODS: T, Tn and sjalyl-Tn antigens were examined in 72 consecutive primary breast carcinomas by immunohistochemistry using well defined monoclonal antibodies and their semiquantitative values were correlated with established clinicopathologic prognostic parameters of the disease to determine their relationship with long-term clinical outcome. RESULTS: Of the 72 carcinomas, 63 (87.5%) each expressed T or Tn antigens, while 16 (22%) expressed sialyl-Tn antigens. Most carcinomas (81%) expressed more than one of the antigens simultaneously, being the most frequent combination T/Tn antigen expression. No significant correlation was noted between the expression of T, Tn and sialyl-Tn antigens (whether individually or in combination) and the prognostic parameters including patient age, disease stage, tumor size, lymph node status, nuclear and histologic grades, histologic types, hormone receptor status and menopausal status. Univariate survival analyses showed that disease stage, tumour size and lymph node metastasis were significant predictors of overall survival. Interestingly, a significant inverse correlation was found between the Tn antigen expression (p = 0.04), as well as the combined T/Tn (p = 0.03) and Tn/sialyl-Tn (p = 0.02) antigen expressions and long-term overall survival. In a multivariate Cox proportional hazard model, disease stage and a negative or low Tn antigen expression emerged as significant predictors of overall survival. CONCLUSION: Our data suggested that the expression of T, Tn and sialyl-Tn antigens does not appear to predict the outcome of patients with breast carcinoma in a long-term run. Moreover, the findings signified a potential value for a negative or low Tn antigen expression in prognostic stratification of breast carcinomas.

G-CSF producing malignant fibrous histiocytoma in the jejunum: a case report.

Malignant fibrous histiocytoma arising from the alimentary tract is extremely rare. We experienced a young patient with an inflammatory type of malignant fibrous histiocytoma in the jejunum which produced granulocyte-colony stimulating factor. A 16-year-old male was admitted to Umehara Hospital with abdominal pain, frequent vomiting of 2 days' duration, high fever and leukocytosis. Serum level of granulocyte-colony stimulating factor was 61.2 pg/mL. Plain abdominal X-ray, ultrasonography and computed tomography led to the diagnosis of intussusception with small intestinal tumor. On the 2nd hospital day, the patient underwent exploratory laparotomy. The jejunum showed intussusception with a hen's egg-sized tumor. After manual reduction, a 20-cm segment of the jejunum was removed. The patient was alive and doing well 29 months after the operation. Microscopic examination of the resected tumor disclosed an inflammatory type of malignant fibrous histiocytoma in the jejunum, and immunohistochemistry was positive for granulocyte-colony stimulating factor. This is the 5th case of malignant fibrous histiocytoma arising from the small intestine that has been described in the English literature.

Fine needle aspiration cytology for soft tissue tumours of the hand.

The purpose of this study was to evaluate the usefulness of fine needle aspiration cytology for the preoperative diagnosis of soft tissue tumours of the hand. Fine needle aspiration cytology was performed on 93 soft tissue tumours of the hand which were classified as malignant, benign or unclassified based on cytological findings. We also attempted to make specific diagnosis by cytology. The cytological diagnosis was then compared with the postoperative histopathological diagnosis. The cytological differentiation between benign and malignant tumours showed neither false-positive nor false-negative results. Of the 47 lesions with sufficient material for cytology and that were postoperatively diagnosed histologically, 35 (including one recurrent lesion) were correctly diagnosed by fine needle aspiration cytology. No complications were encountered. Fine needle aspiration cytology has a high degree of diagnostic accuracy and safety for soft tissue tumours of the hand.

Overexpression and localization of heat shock proteins mRNA in pancreatic carcinoma.

In the present study we examined the localization and overexpression of heat shock proteins (hsps), mainly hsp90, in pancreatic carcinoma tissue compared with control tissue (including chronic pancreatitis and normal pancreas tissue), with the aid of immunohistochemical staining, in situ hybridization and reverse transcriptase polymerase chain reaction. Hsp90 alpha mRNA was overexpressed more highly in pancreatic carcinoma than in the control tissue. The proliferating-cell-nuclear-antigen labeling index was also high in pancreatic carcinoma tissue compared with the other tissue. These findings suggest that the overexpression of hsp90 alpha mRNA in carcinomas may be correlated with cell proliferation. However, hsp90 beta was constitutively overexpressed almost equally in all groups of pancreatic tissue including pancreatic carcinoma, chronic pancreatitis and normal pancreas tissue. Immunohistochemical staining demonstrated a differentiation in the expression of hsp90 between histological types of pancreatic carcinoma. These findings suggest that hsp90 alpha is involved in carcinogenesis and that hsp90 beta is correlated to structural conformation. Hsp90 alpha and hsp90 beta seem to perform different functions in tissue containing malignant cells. P53, MDM2 and WAF1, that were cell-cycle-related oncogene product were more strongly expressed in the nuclei of the cancer cells of the cancer tissue. Especially, MDM2 was more strongly expressed in mucinous carcinoma and the mucin secreting tissues surrounding pancreatic carcinoma tissue. The expression of MDM2 protein might also be correlated to secretion systems during structural conformation and be correlated to hsp90 beta.

Hemorrhagic gastric carcinoma in an acromegalic patient.

A rare case of hemorrhagic gastric carcinoma in an acromegalic patient is reported. A 79-year-old Japanese man was referred to our hospital with diagnoses of upper gastrointestinal hemorrhage and angina pectoris. This patient showed typical clinical features of acromegaly, with increased serum growth hormone (GH) and insulin-like growth factor I (IGF-I) level. A high titer of serum anti-Helicobacter pylori (H. pylori) IgG was also observed. After percutaneous transluminal coronary angioplasty treatment for stenosis of the right coronary artery, the patient underwent distal gastrectomy. Gastric cancer was Type 2 macroscopically and was diagnosed histologically as a papillary and well to moderately differentiated tubular adenocarcinoma. Reverse transcription-polymerase chain reaction analysis estimated that the amount of IGF-I receptor mRNA expression in the gastric cancer tissue was 1.6 times higher than that in the adjacent atrophic mucosa, whereas the amount of IGF-I mRNA expression in the cancer tissue was only half that in the atrophic mucosa. Both the stimulatory effects of GH and/or IGF-I on cell proliferation and H. pylori infection in gastric tumorigenesis may have been responsible for the development and growth of gastric carcinoma in this patient.

Triple-staining to identify apoptosis of hepatic cells in situ.

To identify apoptosis of nonparenchymal cells in fibrotic livers, we established a triple staining method which combined immunohistochemistry for cell markers and Masson staining for collagen as well as terminal deoxynucleotidyl transferase UTP nick end labeling (TUNEL). Five microm formalin fixed, paraffin-embedded liver sections were prepared for staining. Firstly, TUNEL staining was carried out to detect apoptosis of liver cells. Then, the sections were subjected to immunohistochemistry for alpha-smooth muscle actin (alpha -SMA) or KP-1 to identify hepatic stellate cells or Kupffer cells. Finally, Masson staining was performed to show the relationship between apoptosis and collagens. In addition, we optimized different conditions of fixation, digestion and color development which may affect the results.

Localization of extracellular matrix and mitogen-activated protein kinase (MAPK) in aorta of streptozotocin treated Mongolian gerbils.

To evaluate the relationship among the extracellular matrix (ECM) and mitogen-activated protein kinase (MAPK) family for the vascular damages in hyperglycemia, we injected Mongolian gerbils intravenously with 150 mg/kg streptozotocin (STZ) and observed over the next one year the resulting aortic changes by immunohistochemical techniques. After STZ treatment, hyperglycemia was confirmed. At 4 weeks after STZ administration morphological observation revealed increased stromal components among the vascular smooth muscle cells (SMCs). Immunohistochemically, extracellular matrices such as fibronectin and laminin were localized in the aorta at 4 weeks and one year after STZ administration. The reaction products of MAPK in vascular SMCs were more increased at one year than at 4 weeks after STZ administration. After STZ administration, the increase of ECM and MAPK was observed in the aorta, which suggests these factors play important roles in the pathogenesis of macrovasculopathy in diabetes mellitus.

Expression and localization of basic fibroblast growth factor and its mRNA in solitary fibrous tumor.

Solitary fibrous tumors (SFTs) represent a distinct neoplasm that should be included in the differential diagnosis of spindle-cell neoplasms of the soft tissue. Basic fibroblast growth factor (bFGF or FGF-2) is a mitogenic and angiogenic polypeptide produced by diverse cell types, including the cells derived from normal tissue and neoplastic lesions. In this study, the expression of bFGF, vimentin, CD 34, c-kit (or CD 117), desmin, S-100 protein, and alpha-smooth muscle actin (alpha-SMA) in SFTs, hemangiopericytomas (HPC), gastrointestinal stromal tumors (GIST), and dermatofibrosarcoma protuberans (DFSP) were evaluated to assess their usefulness in the differential diagnosis of these lesions. The expression of bFGF mRNA was also examined in SFTs by in situ hybridization (ISH) using a digoxigenin-labeled bFGF oligonucleotide probe. All the SFTs, GISTs and DFSPs exhibited strong and diffuse immunoreactivity for CD34 and vimentin, and were completely negative for desmin, S-100 protein and alpha-SMA. The HPCs were positive for vimentin, but negative for CD34. In all the SFTs, strong and diffuse nuclear immunostaining was observed with bFGF antibody, contrasting with the negative staining observed in the majority of the HPCs, GISTs, and DFSPs. The bFGF mRNA was also expressed in the SFT cells. The constitutive expression of the bFGF in the SFT widens the spectrum of available markers for these tumors, providing a useful addition to their differential diagnosis in difficult cases, and contributing to the understanding of their histogenesis and molecular pathogenesis.