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p63 is a p53-related gene mapping to 3q28 that codes for multiple mRNA transcripts with (TA-p63) or without (DeltaN-p63) transactivating effects on genes that promote cell differentiation and apoptosis. We analysed p63 alterations by immunohistochemistry, quantitative real-time RT-PCR and FISH in a series of 45 follicular lymphomas (FL). None of the tumours showed immunoreactivity for the p40 antibody, which recognizes only the truncated isoforms of p63, or DeltaN-p63 mRNA expression. Immunoreactivity for the 4A4 antibody, which recognizes both the transactivating and the truncated p63 isoforms, was found in 5 +/- 5.5%, 6.85 +/- 4.88% and 33.2 +/- 22.31% of grade I, II and III FL cells, respectively (p < 0.0001). Quantitative RT-PCR analysis showed that all cases but one had TA-p63 mRNA levels higher than non-neoplastic lymphocytes, and that TA-p63 mRNA expression correlated significantly (r = 0.9194, p < 0.0001) with the prevalence of p63 immunoreactivity. FISH extra signals for the p63 gene were found in seven (23.3%) of the 30 cases analysed (0/6 grade I, 2/15 grade II and 5/9 grade III; p = 0.01937). Further hybridizations showed a pattern highly suggestive of chromosome 3 polysomy in six cases. One of these cases also bore extra copies of the p63 and bcl-6 genes. Co-localization of p63 and IgH signals was found in one case. No association between the prevalence of p63 immunoreactivity and extra p63 gene signals was detectable when the cases were dichotomized according to a p63 immunoreactivity threshold of 10%. Our data suggest that TA-p63 is overexpressed in high-grade FL, possibly independent of the occurrence of gene abnormalities, and that it may be involved in the highly complex mechanism of regulation of apoptosis of FL cells., (Copyright 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.)

HER-2/neu oncogene activation by either gene amplification and/or protein overexpression has been documented in several human malignancies. Irrespective of protein overexpression, HER-2/neu gene amplification is rare in lung cancer and studies on its prevalence and clinicopathological implications in early stage non-small cell lung cancer (NCSLC) and neuroendocrine tumours (NET) of the lung are lacking. We evaluated HER-2/neu abnormalities in 345 Stage I NSCLC and 207 Stage I-III NET of the lung of all the diverse histological types, by using immunohistochemistry and fluorescent in situ hybridization in selected cases. Overall, HER-2/neu immunoreactivity was detected in 23% of 345 NSCLC and in 7% of 207 NET. Gene amplification was seen in only 7 (7.4%) of the immunoreactive tumours, with high-level amplification (HER-2/neu gene to chromosome 17 ratio > 4.0) in 3 adenocarcinomas, 1 squamous-cell carcinoma and 1 large-cell neuroendocrine carcinoma (LCNEC), and low-level amplification (HER-2/neu gene to chromosome 17 ratio from 2.0 to 4.0) in 1 squamous-cell carcinoma and 1 LCNEC. None of tested carcinoids and SCLC showed gene amplification. All but 1 gene amplified case exhibited 2+ or 3+ membrane labeling. No relationship was found between gene amplification or protein overexpression and patients' survival or other clinicopathological variables. HER-2/neu gene amplification and protein overexpression are not closely correlated in lung carcinomas and do not bear any prognostic implication. Among neuroendocrine tumours, LCNEC show a slightly higher prevalence of either HER-2/neu gene amplification or protein overexpression.

Purpose: To analyze the prevalence and clinical relevance of cyclin D3 abnormalities in laryngeal squamous cell carcinoma (LSCC)., Experimental Design: Cyclin D3 immunoreactivity was evaluated in 223 formalin-fixed and paraffin-embedded samples of LSCC patients with a mean follow-up of 62.8 +/- 43.2 months. The occurrence of cyclin D3 extra signals was analyzed by fluorescence in situ hybridization in 47 randomly selected cases collected in a tissue microarray. Cyclin D1 immunoreactivity had been previously investigated in 133 cases., Results: Cyclin D3 immunoreactivity and gene extra signals were found in 39.5% and 42.6% of the cases, respectively, and the concordance between immunohistochemical and fluorescence in situ hybridization results was 70.2% (P = 0.0085). Cyclin D3 immunoreactivity was significantly associated with a high risk of death. Multivariate analysis showed that high tumor grade, exophytic/ulcerating tumor type, low performance status, and cyclin D3 immunoreactivity were the only independent predictors of poor overall survival. In the 133 cases analyzed for both cyclin D1 and cyclin D3, patients with cyclin D1+/cyclin D3+ tumors experienced the worst prognosis, patients with cyclin D1-/cyclin D3- exhibited the most prolonged survival, and with cyclin D1-/cyclin D3+ or cyclin D1+/cyclin D3- tumors an intermediate course was associated., Conclusions: Our data suggest that cyclin D3 immunoreactivity, possibly due to the occurrence of gene extra copies, may represent an adjunct in LSCC patients' prognostication and contribute to identify D-type cyclins as potential targets of newly developed therapies.

An abnormal expression of cyclin D3, a key regulator of the cell cycle, has been documented in a variety of human malignancies, and the cyclin D3 gene, mapping to 6p21, may be deregulated in plasma cell myeloma and non-Hodgkin's lymphoma as a result of the t(6;14)(p21.1;q32.3) translocation and/or gene amplification. In the current study, we for the first time investigated by immunohistochemistry and fluorescence in situ hybridization (FISH) the prevalence of cyclin D3 abnormalities in follicular lymphomas (FLs), comparing the results with traditional clinicopathologic characteristics, p27 and skp2 immunoreactivity (IR) and Ki-67 labeling index (LI). Cyclin D3, skp2 and Ki-67 IR significantly increased from grade I to grade III FL (p = 0.0003, p = 0.0001 and p < 0.0001, respectively), while p27 IR was significantly (p < 0.0001) more prevalent in low-grade tumors. Cyclin D3 IR was directly correlated with the Ki-67 LI (p < 0.0001) and inversely correlated with p27 IR (p = 0.050). None of the 13 cases analyzed by FISH showed the t(6;14) translocation, but in 2 (15.3%) grade I FLs 3 cyclin D3 signals were detected. Cohybridization with probes specific for the centromeric region and the long arm of the chromosome 6 indicated trisomy in one case and a pattern highly suggestive for the presence of an isochromosome 6p in the other case. Our data suggest that the t(6;14) translocation may be extremely uncommon in FL and that a deregulated expression of cyclin D3, possibly due to epigenetic mechanisms, may be involved in the pathogenesis of high-grade tumors.

An abnormal expression of cyclin D3, a key regulator of the cell cycle, has been documented in a variety of human malignancies, and the cyclin D3 gene, mapping to 6p21, may be deregulated in human tumors as a result of the t(6;14)(p21.1;q32.3) translocation or gene amplification. In the current study, we for the first time investigated by immunohistochemistry and fluorescence in situ hybridization (FISH) the prevalence of cyclin D3 abnormalities in gastrointestinal stromal tumors (GISTs), comparing the results with traditional pathological characteristics, p27 immunoreactivity (IR), and Ki-67 labeling index (LI). All the tumors showed nuclear cyclin D3 IR, with a percentage of immunostained neoplastic cells ranging from 10 to 95% (mean, 67.3 +/- 22.9%). In 4 (40%) of the 10 cases analyzed by FISH, cyclin D3 extrasignals were detected. Cohybridization with probes specific for the centromeric region and the long arm of chromosome 6 indicated trisomy in one case, whereas in the remaining three cases the pattern was highly suggestive for the occurrence of an isochromosome 6p. There was no association between the cyclin D3 gene copy number and IR for the encoded protein. Cyclin D3 IR was positively associated with p27 IR (P =.004) but not with Ki-67 LI or tumor malignant potential. On the contrary, p27 IR was inversely associated with Ki-67 LI (P =.004) and was more prevalent in tumors of low or intermediate malignant potential, though at a borderline level of statistical significance (P =.066) only. These data suggest that cyclin D3 expression in GISTs is independent of gene amplification and that this protein may be involved in the pathogenesis of GISTs by counteracting the inhibitory activities of p27.

Cyclin D3 plays a pivotal role in controlling the physiological progression from the G1 to the S phase of the cell cycle. Recent data suggest that cyclin D3 may be deregulated in extranodal non-Hodgkin's lymphomas (NHLs) as a consequence of the t(6;14)(p21.1;q32.3) translocation. The present study investigated for the first time by dual-colour fluorescence in situ hybridization (FISH) on interphase nuclei and immunohistochemistry the prevalence of the t(6;14) translocation and cyclin D3 immunoreactivity (IR) in a series of 29 stage I-IIE primary gastric NHLs (PGLs). No case showed the t(6;14) translocation. However, in five (17.2%) cases (two extranodal marginal zone lymphomas of MALT type, LGM; one diffuse large-cell lymphoma with a MALT component, DLCLM; and two diffuse large-cell lymphomas without a MALT component, DLCL), three to four cyclin D3 signals were detected by FISH. Co-hybridization with probes specific for the centromeric region and long arm of chromosome 6 indicated trisomy in one case (DLCL), whereas in the remaining four cases the pattern was highly suggestive of the presence of an isochromosome 6p. One (12.5%) case of LGM, six (75%) cases of DLCLM, and seven (53.8%) cases of DLCL (p = 0.0378) were immunoreactive for cyclin D3. Cyclin D3 IR was detected in two (40%) of the five cases with extra cyclin D3 signals and in 12 of the remaining 24 cases (50%, p = 1.000). These results suggest that the t(6;14) may represent a rare event in the pathogenesis of PGL and that cyclin D3 deregulation is most likely the result of epigenetic mechanisms., (Copyright 2003 John Wiley & Sons, Ltd.)

Clear cell mesothelioma is an extremely rare neoplasm of the pleura, which can easily be mistaken for a metastasis of clear cell carcinoma to the pleura. We report here the histochemical, immunohistochemical, and ultrastructural aspects of a new case of clear cell pleural mesothelioma in a 52-year-old man with no known asbestos exposure. He was admitted to the hospital for recurrent pleural effusion, which was negative for neoplastic cells at the cytologic examination. A partial decortication of the right pleura was performed. The morphologic, immunohistochemical, and ultrastructural features reported for this case are consistent with the diagnosis of clear cell mesothelioma. The differential diagnosis and immunohistochemical features in comparison with other clear cell neoplasms are discussed.

Meningiomas are common, usually benign slow-growing neoplasms of the central nervous system thought to arise from meningocytes capping arachnoid villi. Primary ectopic meningiomas are exceedingly rare extracranial and extraspinal tumors of controversial origin; they are usually limited to the head and neck region or to the paravertebral soft tissues. Only one mediastinal ectopic meningioma and few pulmonary ectopic meningiomas have been described in the literature until now. Because of their rarity and their intriguing pathogenesis, we report here a second case of primary mediastinal meningioma and an additional case of primary pulmonary meningioma. Their possible origin and differential diagnosis are discussed.

Aim of this work was to investigate the ability of the antibodies against Surfactant proteins (SP) and Thyroid transcription factor 1 (TTF-1) to distinguish primary neoplasms of the lung from metastatic carcinomas to the lung and pleural mesotheliomas. We evaluated the immunohistochemical expression of the antibodies anti SP-A, SP-B, pro SP-C, SP-D, and TTF-1 in a series of 56 primary lung carcinomas, 9 metastatic carcinomas to the lung, 5 pleural mesotheliomas and 8 non-pulmonary carcinomas. Among primary lung neoplasms, only adenocarcinomas immunostained for all SP (specificity = 1; total sensitivity = 0.52). TTF-1 had an excellent specificity (= 1), but a weak sensitivity (= 0.34) in recognizing primary lung carcinomas. TTF-1 was present in lung adenocarcinomas which were negative for SPs; however it failed to distinguish the subtypes. Pleural mesotheliomas, pulmonary metastases and non-pulmonary carcinomas were not immunoreactive for SP-A, SP-B, SP-D, and TTF-1. Pro SP-C was positive also in the adenocarcinomas of the large bowel and in their pulmonary and nodal metastases. These results demonstrate that the combined use of antibodies anti SP-A, SP-B and TTF-1 is the best association in distinguishing primary lung carcinomas from metastatic carcinomas to the lung and pleural mesotheliomas.

Intravascular Lymphomatosis (IL) is a rare and usually aggressive form of non-Hodgkin's lymphoma characterized by the growth of neoplastic cells within vascular lumina that usually presents with skin or central nervous system (CNS) involvement. The mechanism(s) for the selective intravascular growth of this neoplasm remain(s) unexplained. We now report clinical and immunohistologic data on surgical material from 6 cases of IL; in 4 of 6 cases, autopsies were performed. Our IL cases shared the following features: (1) B-cell lineage; (2) lack of skin involvement at presentation; (3) aggressive behavior; and (4) lack of extravascular lymphomatous masses; in addition, 1 case had an associated gastric low-grade MALT lymphoma. We studied by immunohistochemistry formalin-fixed, paraffin-embedded sections with monoclonal antibodies to molecules known to be involved in lymphocyte and endothelial adhesion phenomena, that is, CD29 (beta1 integrin subunit), CD43 (leukosialin), CD44 (H-CAM), CD54 (ICAM-1), embryonal N-CAM (e-NCAM), and EMA (episialin). In all cases, the surfaces of IL aggregates reacted for CD44 but were consistently negative for CD29; also absent was CD54. Conversely, the integrity of the endothelial cells was underscored by their even reactivity for CD29, CD44, and CD54. Given that CD29 is currently regarded as critical for lymphocyte trafficking in general and for transvascular migration in particular, and CD54 is also involved in transvascular lymphocyte migration, we conclude that their consistent absence in IL may contribute to its intravascular and disseminated distribution pattern. The rather frequent association of IL with various conventional lymphomas is known; yet, one of our cases appears to be the first report of IL associated with a low-grade MALT lymphoma.