Fibroblast growth factor receptor 3 is overexpressed in urinary tract carcinomas and modulates the neoplastic cell growth.

PURPOSE: Fibroblast growth factor receptor 3 (FGFR3) mutations have been associated with achondroplastic syndromes and urinary bladder carcinomas. Here we describe changes in FGFR3 mRNA and protein expression in transitional carcinomas and determine the effect of monoclonal antibodies against FGFR3 in RT-112 cell line proliferation. EXPERIMENTAL DESIGN: We used microarray tools to evaluate FGFR3 mRNA expression in 22 urinary bladder carcinomas at different stages (noninvasive pTa, lamina propria invasive pT1, and muscular invasive pT2) and 7 nonneoplastic tissue controls. FGFR3 protein expression was evaluated by Western blotting in 15 different carcinomas and 3 nonneoplastic controls. Two hundred thirty-seven urinary bladder and renal pelvis carcinomas and 21 negative controls were tested on tissue microarrays by immunohistochemistry. The effect on cell proliferation in the RT-112 bladder cancer cell line of monoclonal antibodies against FGFR3 was also evaluated. RESULTS: Overexpression of FGFR3 mRNA was found in pTa and pT1 stage carcinomas (fold change >8) and in pT2 carcinomas (fold change >4). Nonneoplastic urinary bladder samples do not express FGFR3 protein. However, 83% of pTa, 100% of pT1, and 50% of pT2 carcinomas expressed FGFR3 as determined by Western blotting. By immunohistochemistry, FGFR3 was positive in 71.4% of pTa, 72% of pT1, and 49.2% of pT2 cases as well as 61.5% of upper urinary tract carcinomas. Proliferation of the RT-112 cell line was inhibited with monoclonal antibodies against FGFR3. CONCLUSIONS: FGFR3 seems to play an important role in transitional cell carcinoma development. Our results suggest that FGFR3 antagonists could be developed as possible therapeutics for treatment of urinary tract carcinoma.

Clinicopathologic study and DNA analysis of 37 cardiac myxomas: a 28-year experience.

PURPOSE: This study was performed to identify morphologic features of cardiac myxomas related to embolism and to provide a better understanding of the biology of these tumors, mainly in relation to their interleukin (IL)-6 expression and DNA content. PATIENTS AND METHODS: A total of 37 cardiac myxomas were reviewed retrospectively in a clinicopathologic study that included the correlation of echocardiographic and pathologic findings in 25 cases, together with immunohistochemical evaluation of IL-6 expression and flow cytometric DNA analysis of 35 tumors. RESULTS: There were 24 female patients and 13 male patients. The mean (+/- SD) age was 52 +/- 15 years. Fifty-four percent of patients presented with dyspnea, 51% presented with increased erythrocyte sedimentation rate (ESR), and 27% presented with embolic episodes, which were significantly associated with villous surface tumors. Atrial fibrillation was registered in 19% of patients and was significantly associated with large left atrial myxomas. Echocardiography proved to be a reliable method for preoperative diagnosis and for predicting tumor size and morphology. There was no perioperative mortality or long-term recurrences. The frequency of early surgical complications was associated with a longer mean ischemic time. Seventeen percent of tumors had abnormal DNA content, and 74% of tumors showed immunohistochemical expression of IL-6. Neither of these factors showed a significant association with embolism or constitutional illness. CONCLUSIONS: Villous surface myxomas are related to embolism, and large left atrial tumors are related to atrial fibrillation. Echocardiography is a reliable method with which to predict tumor size and morphology. Myxoma cells usually express IL-6, and some tumors have abnormal cellular DNA content. Surgical excision of the tumor is a safe and effective treatment.

Incidental localized (solitary) epithelial mesothelioma of the pericardium: case report and literature review.

Primary mesotheliomas of the pericardium are rare tumors. They may occur in diffuse, multiple, and localized forms. Most of the pericardial mesotheliomas are multiple or diffuse growths encasing the heart, localized forms being distinctly uncommon. We report a localized mesothelioma of the pericardium found incidentally at the autopsy of a 76-year-old woman. The neoplasm measured 3.6 x 2.4 x 2.5 cm., was well circumscribed, and affected the entire thickness of the myocardium extending from the epicardium to the endocardium of the anterior wall of the right ventricle. The tumor was epithelial in type, showed an immunohistochemical profile compatible with mesothelioma, and was DNA aneuploid. A review of the literature yielded four cases of localized pericardial mesothelioma, including the present. Most cases are seen in women and are of the epithelial variant. There is a wide age range at presentation. Localized mesotheliomas are capable of aggressive behavior. Nevertheless, in contrast to diffuse tumors, complete surgical excision may be curative. Differential diagnosis includes solitary fibrous tumor, synovial sarcoma, epithelioid angiosarcoma, and adenomatoid tumor of the pericardium.

Plexin B1 is downregulated in renal cell carcinomas and modulates cell growth.

Plexins are a family of transmembrane receptors that interact with the repulsive axon guidance molecules (Semaphorins) in neural tissues. In extraneural tissues, plexins are involved in other cellular functions often altered in neoplastic cells, such as adhesion, migration, and apoptosis. Plexin B1 has been implicated in the regulation of Akt, which is an activated pathway in renal cell neoplasms, and only 1 report has emphasized its role as an oncogenic factor. Furthermore, plexin B1 is located in 3p21, which is a chromosomal region deleted frequently in renal cell carcinomas. In accordance with a hypothetical oncogenic role for plexin B1, we have shown by reverse transcription-polymerase chain reaction that plexin B1 is expressed in nonneoplastic renal tissue, and it is severely downregulated in clear cell renal carcinomas. We have also demonstrated by immunohistochemistry on tissue microarrays that plexin B1 protein is absent in more than 80% of renal cell carcinomas (169 in 209 carcinomas examined). Otherwise, all kinds of renal tubules showed strong membrane reactivity. Moreover, when we have induced plexin B1 expression with an expression vector in the renal adenocarcinoma cell line ACHN, a marked reduction in proliferation rate was produced. Altogether, this evidence suggests a possible role for plexin B1 in renal oncogenesis.

Recurrence of bronchioloalveolar carcinoma in donor lung after lung transplantation: microsatellite analysis demonstrates a recipient origin.

Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post-transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non-mucinous bronchioloalveolar carcinoma in a 43-year-old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty-five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non-mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease.

Anticipated diagnosis of left atrial myxoma following histological investigation of limb embolectomy specimens: a report of two cases.

Nonfamilial myxoma occurs as a random event. The tumor is rare and can mimic other diseases. Cardiac myxomas should always be considered as a source of embolization, which need meticulous investigation and prompt indication of surgical resection. Tumors with a villous surface are prone to embolize. We report two cases of cardiac myxoma presenting as acute ischemia of one or two limbs due to embolic phenomena. The patients were females aged 55 and 37 years. Histological study of emboli taken from obstructed limb arteries in the two patients showed a picture indicating systemic embolization of a cardiac myxoma. The embolic tissue fragments showed the gross characteristics (i.e. villous surface) of the cardiac tumor. Further echocardiography and surgical removal confirmed the cardiac myxoma. Immunohistochemical study of embolectomy material disclosed strong reactivity of the tumor cells for calretinin. The histological examination of the embolectomy material can anticipate the cardiac lesion and its gross features. Calretinin is a useful marker in the differential diagnosis of cardiac myxoma with a myxoid thrombus. The necessity of histological examination of the embolectomy material is stressed.

Fibroepithelioma of pinkus with tumor giant cells.

A case of fibroepithelioma of Pinkus with pleomorphic epithelial giant cells is reported. The lesion was an ovoid polypoid nodule measuring 4 mm x 3 mm x 2 mm and was located close to the right axilla in an 86-year-old woman. The immunohistochemical features of the epithelial giant cells indicate that most of these cells are not cycling. We suggest that these cellular changes may represent a senescent event. Giant cells showed a mean nuclear major diameter more than twice that of small cells. Flow cytometric study of the tumor showed a hypodiploid DNA content and an intermediate grade S-phase fraction of the aneuploid component. To the best of our knowledge, a pleomorphic variant of Pinkus fibroepithelioma has not been reported to date. In fibroepithelioma of Pinkus, the correct diagnosis depends primarily on the architectural pattern of the tumor rather than on its cytologic features.