Predominant tubulointerstitial nephritis in a patient with systemic lupus erythematosus: phenotype of infiltrating cells.

A 63-year-old man with systemic lupus erythematosus developed tubular proteinuria. All subclasses of serum IgG increased, and the largest IgG subclass increase was IgG4. A renal biopsy showed lupus nephritis (Class II) with severe tubulointerstitial nephritis (so-called predominant tubulointerstitial lupus nephritis, an unusual form of lupus nephritis). Immunofluorescence microscopy revealed positive granular staining for IgG, C3 and C1q in the mesangium and peritubular interstitium, and along the tubular basement membranes (TBM). Electron microscopy also showed electron-dense deposits in the mesangium and TBM. Immunophenotyping of interstitial infiltrating cells disclosed a predominance of T cells. CD8-positive cytotoxic T cells infiltrated the peritubular interstitium, and some of these cells infiltrated the tubules. B cell-rich lymphoid follicles were also observed. IgG subclass analyses showed glomerular IgG1, IgG2 and IgG4 deposition, positive staining of IgG4 in the peritubular interstitium and along the TBM, and abundant IgG1-, IgG3- and IgG4-positive plasma cells in the interstitium. The patient responded well to moderate-dose steroid therapy. This is the first report of immunophenotyping of interstitial infiltrates in predominant tubulointerstitial lupus nephritis. The results suggest CD8-positive cytotoxic T cell-mediated tubular injury. Furthermore, immune complexes containing IgG4 might be one of etiologic factors.

PTC gene mutations and expression of SHH, PTC, SMO, and GLI-1 in odontogenic keratocysts.

The Patched (PTC) gene is responsible for basal cell nevus syndrome (BCNS) accompanied by multiple odontogenic keratocysts (OKCs), and its product plays a role in the Sonic hedgehog (SHH) signaling pathway involving smoothened (SMO) and GLI-1. To clarify the role of SHH signaling in OKCs, the expression of SHH, PTC, SMO, and GLI-1 and mutations of PTC were examined in 18 sporadic, 4 BCNS-associated OKCs and 7 control gingivae. SHH, PTC, SMO, and GLI-1 were detected in all OKC and gingiva samples by reverse transcriptase-polymerase chain reaction (RT-PCR). Immunoreactivity for SHH and GLI-1 was markedly higher in epithelial components than in subepithelial cells, while immunoreactivity for PTC and SMO was similar in epithelial components and subepithelial cells in OKCs. The positive rate of PTC and SMO expression in subepithelial cells of OKCs was significantly higher than that in gingivae. The positive rate of GLI-1 expression in subepithelial cells of BCNS-associated OKCs was significantly higher than that in primary OKCs. These results suggest that the SHH signaling might be involved in the pathophysiologic nature of OKCs. While mutations of the PTC gene could not be detected in 4 BCNS-associated OKCs by direct DNA sequencing, 3 of 5 primary and 4 of 4 recurrent OKCs had several mutations of this gene. These results suggest that PTC mutations are probably related not only to BCNS-associated OKCs but also to sporadic OKCs.

Chromogenic in situ hybridization analysis of HER-2/neu status in breast carcinoma: application in screening of patients for trastuzumab (Herceptin) therapy.

Evaluation of HER-2/neu status is important in the management of patients with breast carcinoma, especially in determining the possible application of trastuzumab, a humanized anti-HER-2/neu monoclonal antibody. Chromogenic in situ hybridization (CISH) detection of the HER-2/neu oncogene is a newly developed in situ hybridization method that utilizes a robust and unique-sequence DNA probe labeled with digoxygenin, and sequential incubations with antidigoxygenin fluorescein, antifluorescein peroxidase, and diaminobenzidine. In this study, we examined 20 archival specimens of human breast carcinoma using CISH, and we correlated findings with immunohistochemical findings for HER-2/neu. HER-2/neu immunohistochemistry was carried out with HercepTest, a standardized immunohistochemical examination system for HER-2/neu overexpression in surgical pathology specimens. CISH analysis could be done in 18 out of 20 cases examined. Gene copy signals for HER-2/neu were recognized as intranuclear brown dots in both neoplastic and non-neoplastic cells. Seven carcinomas showed an increased number or size of signals and were interpreted as being positive for HER-2/neu amplification. Eight cases were positive with the HercepTest. Seven out of eight carcinoma cases found to overexpress immunoreactive HER-2/neu also demonstrated HER-2/neu gene amplification following CISH analysis. There was a significant correlation between immunohistochemical and CISH analyses (P < 0.001). We found that CISH was a specific, sensitive and easily applicable method for the detection of HER-2/neu gene amplification, which may be used together with immunohistochemical examination for the evaluation of patients with breast carcinoma.

Bimodal effects of platelet-derived growth factor on rat mesangial cell proliferation and death, and the role of lysophosphatidic acid in cell survival.

Although mesangial cell death has been shown to be correlated with mesangial cell mitosis in vivo, little is known about how these two apparently opposite events are regulated. We show that the addition of platelet-derived growth factor (PDGF; 10-50 ng/ml) to primary cultured rat mesangial cells for 24 h caused continuous proliferation along with simultaneous cell death. This process was accompanied by the fragmentation of DNA into nucleosomal oligomers, the development of apoptotic morphological changes in the nucleus, and increased expression of p53. Accumulation of lactate dehydrogenase (LDH) was also observed in the culture medium, suggesting that both apoptosis and necrosis are involved in the cell death mechanisms observed. We also observed that addition of 30 microM lysophosphatidic acid (LPA) to the culture medium greatly suppressed PDGF-induced cell death, leading to synergistically enhanced mesangial cell proliferation. DNA fragmentation, p53 expression and LDH release were all suppressed by LPA. We suggest that PDGF is a bifunctional molecule in mesangial cells that evokes both cell proliferation and cell death simultaneously, whereas LPA is a survival factor. We speculate that PDGF and LPA may play important roles in the progression or exacerbation of proliferative glomerulonephritis.

Genetic analysis of DNA microsatellite loci in salivary gland tumours: comparison with immunohistochemical detection of hMSH2 and p53 proteins.

To investigate genetic alterations in salivary gland tumours, microsatellite instability at eight representative loci and loss of heterozygosity (LOH) on chromosome 17 were analysed by polymerase chain reaction amplification. The results were compared with immunohistochemical expression of the hMSH2 and p53 proteins. Microsatellite instability and expression loss of hMSH2 protein were not recognized in the salivary gland tumours, suggesting a low frequency of abnormalities of the mismatch repair system. LOH associated with the p53 gene was detected in approximately one-half of pleomorphic adenomas and salivary carcinomas, which often showed strong p53 immunoreactivity. These features suggest that the p53 gene plays an important role in malignant transformation of salivary gland tumours. The genetic characteristics of pleomorphic adenomas might reflect a low-grade potential for malignant progression.

Alveolar soft-part sarcoma of the cheek: report of a case with a review of the literature.

An alveolar soft-part sarcoma (ASPS) occurring in the cheek is described, with a review of the literature. The subject was a 25-year-old woman who presented with a large swelling in the left cheek. The lesion, initially diagnosed as a benign tumor on radiographic and computed tomographic examinations, was surgically excised. Histopathological examination of the mass revealed a nest-like or organoid cellular arrangement as confirmed by three-dimensional computer graphic reconstruction. The cytoplasm of the large polygonal tumor cells contained abundant diastase-resistant, PAS-positive inclusions, ultrastructurally confirmed to be crystalloid materials. The tumor cells were immunoreactive for anti-myoglobin, sarcomeric actin, and neuron-specific enolase antibodies, suggesting a myogenic origin.

Analysis of the PTEN gene mutation in polyposis syndromes and sporadic gastrointestinal tumors in Japanese patients.

PURPOSE: PTEN is a candidate tumor suppressor gene for mutations which are responsible for Cowden disease. Recently, it has been shown that PTEN is mutated in several human neoplasms. To investigate the role of PTEN in tumorigenesis, we screened its mutation in Japanese patients with gastrointestinal polyposis and various sporadic tumors. METHODS: The entire coding region of PTEN was screened by single strand conformational polymorphism or direct sequencing for somatic mutations in 16 gingival papillomas, 4 juvenile polyps, 10 esophageal papillomas, and 20 colorectal cancers and for germline mutations in three patients with Cowden disease (including one with Lhermitte-Duclos disease) and one patient each with juvenile polyposis syndrome, Turcot's syndrome, and Cronkhite-Canada syndrome. RESULTS: Germline mutations were found in all cases of Cowden disease. One mutation was a nonsense mutation at codon 130 (CGA-->TGA), and the other two were splice site mutations at the 5' site of intron 4 and the 3' site of intron 8. We could not detect germline mutations in other patients with gastrointestinal polyposis or somatic mutations in sporadic tumors. CONCLUSIONS: We confirmed previous reports that germline mutations in PTEN are responsible for Cowden disease. However, somatic mutations of PTEN may not play a major role in tumorigenesis, at least in colorectal cancers, esophageal papillomas and gingival papillomas.

Prognostic significance of CD56 expression for ALK-positive and ALK-negative anaplastic large-cell lymphoma of T/null cell phenotype.

Anaplastic large cell lymphoma (ALCL) is a distinct entity of non-Hodgkin lymphoma, characterized by a proliferation of pleomorphic large lymphoid cells that express CD30. Recent studies have found that a subset of ALCL aberrantly expresses a chimeric anaplastic lymphoma kinase (ALK) protein as a result of t(2;5)(p23;q35) or variant translocations. ALK-positive ALCLs feature good prognosis, but some of them lead to poor outcomes. Since CD56 is expressed in some ALCLs, its clinical significance was examined in a series of T/null cell type ALCLs. Of 143 patients, 83 (58%) showed ALK-positive staining, and of 140 patients, 25 (18%) expressed CD56. The ALK-positive subgroup was characterized by a younger age of onset (P <.0001), lower serum lactate dehydrogenase level (P =.01), better performance status (P =.03), less frequent extranodal involvement (P =.01), lower international prognostic index (IPI) categories (P =.002), and superior survival (P =.0009) in comparison with the ALK-negative group, suggesting that ALK is a specific marker defining a distinct subtype. CD56(+) cases showed a significantly poor prognosis overall (P =.002) as well as in both ALK-positive and ALK-negative subgroups (P =.02 and P =.04, respectively). Multivariate analysis confirmed that CD56 is independent of other prognostic factors, including IPI. Although CD56(+) cases showed a higher incidence of bone involvement, no other differences in clinicopathologic parameters were found between the CD56(+) and CD56(-) groups. These findings suggest that CD56 is not a marker to identify a distinct subtype of ALCL, but a strong clinical prognostic factor. Effective therapeutic approaches should be explored for high-risk ALCL patients, who can be identified by means of a prognostic model, including CD56.

A histopathological study of lymphoepithelial island formation in labial salivary glands in patients with primary Sjögren's syndrome.

The proliferative status of lymphoepithelial islands in the labial salivary glands of primary Sjögren's syndrome (pSS) patients was investigated by counting the number of argyrophilic nucleolar organizer regions (AgNORs) in epithelial cells constituting the islands. The islands were classified into four groups and evaluated in terms of total area and three discrete zones of the islands. In each pSS group, the mean AgNOR number per total island epithelial cell nucleus was significantly higher than in control ductal epithelial cells. The zonal AgNOR number fluctuated during the process of island formation but became more uniform as the islands developed. Furthermore, statistically significant trends among the four pSS groups were observed in the ratio of T lymphocytes, B lymphocytes and plasma cells surrounding the islands. The results indicated that the islands are highly proliferative once island formation begins and that zonal island cell proliferation may be associated with the inflammatory cells.

[Immunophenotypic analysis in the diagnosis of malignant lymphoma].

Immunophenotypic analysis is capable of distinguishing benign and malignant or determining the lineage of neoplastic cells in most of lymphoproliferative disorders. The methodological approaches can be divided into two major categories; immunohistochemistry and flow cytometry. Both of these techniques can be important adjuncts to histological diagnosis although flow cytometry is not yet common in Japan. The basic features to be checked by immunophenotyping are as follows. IPT-I: Light chain restriction of immunoglobulin. IPT-II: Loss or stronger expression of one or more antigens normally expressed in reactive lymphocytes. IPT-III: Significant increase of a particular cell population that is quite rare or absent from normal tissue at the biopsy site. While IPT-I could be taken as direct evidence of a clonal proliferation of B-lineage cell, IPT-II and -III are the only strong suggestions of a malignant lymphoid proliferation.

Significance of cyclin D1 overexpression for the diagnosis of mantle cell lymphoma: a clinicopathologic comparison of cyclin D1-positive MCL and cyclin D1-negative MCL-like B-cell lymphoma.

Mantle cell lymphoma (MCL) is a distinct clinicopathologic entity of non-Hodgkin's lymphoma, characterized by a monotonous proliferation of small to medium-sized lymphocytes with co-expression of CD5 and CD20, an aggressive and incurable clinical course, and frequent t(11;14)(q13;q32) translocation. We examined 151 cases of lymphoma with MCL morphology from a viewpoint of cyclin D1 overexpression, which is now easily detectable by immunohistochemistry. 128 cases (85%) showed positive nuclear staining for cyclin D1, while the remaining 23 (15%) were negative. Except for cyclin D1 immunohistochemistry, current diagnostic methods, including morphological and phenotypical examinations, could not make this distinction. Although both the cyclin D1-positive and -negative groups were characterized by male predominance, advanced stages of the disease, frequent extranodal involvement, and low CD23 reactivity, the cyclin D1-positive group showed a higher age distribution (P =.04), larger cell size (P =.02), higher mitotic index (P =.01), more frequent gastrointestinal involvement (P =.05), higher international prognostic index score (P =.05), and lower p27(KIP1) expression (P <.0001). Of particular interest is that cyclin D1-positive MCL showed significantly worse survival than cyclin D1-negative lymphoma (5-year survival: 30% versus 86%, P =.0002), which was confirmed by multivariate analysis to be independent of other risk factors. These data suggest that cyclin D1-positive and -negative groups may represent different entities and that the former closely fits the characteristics of classical, typical MCL. We therefore propose that cyclin D1-positivity should be included as one of the standard criteria for MCL, and that innovative therapies for this incurable disease should be explored on the basis of the new criteria.

MSH2-deficient murine lymphomas harbor insertion/deletion mutations in the transforming growth factor beta receptor type 2 gene and display low not high frequency microsatellite instability.

High-frequency microsatellite instability (MSI), defined as more than 20% unstable loci, is an inconsistent finding in hematologic malignancies; consequently, the significance of deficient DNA mismatch repair (MMR) to their pathogenesis has been questioned. To further investigate the relationship between MMR deficiency and genomic instability in hematologic malignancies, this study evaluated MSH2-/- murine lymphomas for insertion/deletion (ID) mutations within the transforming growth factor (TGF)-beta receptor type II (TbetaR-II) gene and MSI at 10 neutral microsatellites. The lymphomas displayed ID mutations within short mononucleotide runs of TbetaR-II at a high frequency, whereas nonmalignant tissue from corresponding animals lacked mutations. Loss of TbetaR-II transcripts and protein was seen in 6 of 7 murine lymphomas harboring acquired TbetaR-II mutations. In the analysis of paired nonmalignant and tumor DNA samples, low-frequency but not high-frequency MSI was found. Low-frequency MSI occurred in 8 of 20 lymphomas and 12 displayed microsatellite stability. MSI was even less frequent in nonmalignant tissue as only 3 of 20 samples displayed low-frequency MSI and 17 displayed stability. Evaluation of 20 single cell clones from the MSH2-/- lymphoma cell lines R25 and L15 identified high-frequency MSI in 4 and 2 clones, respectively. The remaining clones showed low-frequency MSI or stability. These findings suggest that acquired TbetaR-II mutations represent important inactivating events in tumor pathogenesis following MSH2 deficiency. Furthermore, for some hematolymphoid malignancies, the evaluation of cancer-associated genes for ID mutations may represent a more sensitive marker of MMR deficiency than evaluation of neutral microsatellites for high-frequency MSI. (Blood. 2000;95:1767-1772)

Peripheral T-cell lymphoma with distinct perifollicular growth pattern: a distinct subtype of T-cell lymphoma?

Nine cases of peripheral T-cell lymphoma were identified in this study showing a distinctive growth pattern with partial distortion of the lymph node structure and prominent infiltration predominantly of marginal zones by medium-sized cells with clear cytoplasm and significant nuclear atypia. In the paracortical T-zone, there was a marked proliferation of high endothelial venules. Plasmocytosis and capsular fibrosis were other distinctive features. On immunohistochemistry, the lymphomas proved to be of T-helper cell origin (CD3+, CD4+, CD5+/-, CD8-, TIA1-) and proliferation was most prominent in the marginal zone of the regressive B-cell follicles. These cases have a characteristic morphology that may be sufficient to differentiate them as a variant from other peripheral T-cell lymphomas of the "not otherwise specified" group and to include them in the list of currently recognized lymphomas. Because of the distinct perifollicular growth pattern and incomplete effacement of the lymph node architecture, the differential diagnosis consists mainly of marginal zone B-cell lymphoma and reactive lesions.

Ph-negative non-Hodgkin's lymphoma occurring in chronic phase of Ph-positive chronic myelogenous leukemia is defined as a genetically different neoplasm from extramedullary localized blast crisis: report of two cases and review of the literature.

This report describes two cases of Philadelphia chromosome-negative (Ph(-)) non-Hodgkin's lymphomas (NHLs) recognized in patients with chronic phase Ph-positive (Ph(+)) chronic myelogenous leukemia (CML). Lymph node biopsy of patient 1 was initially diagnosed as diffuse large B cell non-Hodgkin's lymphoma (NHL, T cell rich variant), but at relapse showed immunoblastic features with a marked decrease of admixed lymphocyte components. Patient 2 presented with thickened parietal pleura which revealed a CD30-positive anaplastic large cell lymphoma showing null cell phenotype and genotype with abundant admixed neutrophils and lymphocytes. At the time of lymphoma diagnosis, the patients had CML for 33 and 10 months, respectively. DNA obtained from bone marrow cells at the time of lymphoma diagnosis showed BCR/ABL gene rearrangements by both Southern blot analysis and reverse transcription polymerase chain reaction (RT-PCR), but lacked both immunoglobulin and T cell receptor gene rearrangements. BCR gene rearrangement and BCR/ABL fusion gene were also identified in lymph node and pleural biopsies by Southern blot and RT-PCR analysis, respectively. However, both biopsy specimens also contained reactive lymphocytes and neutrophils, and no fusion signals between BCR and ABL genes were identified in the hyperdiploid lymphoma cells of either case by fluorescence in situ hybridization (FISH). These data suggest the lymphoma cells in both cases were not genetically associated with BCR/ABL. Therefore, these cases were not diagnosed as an extramedullary localized blast crisis in CML, but as Ph(-) NHLs. This represents the first definitive demonstration of peripheral B cell lymphoma occurring by a separate genetic pathway, lacking BCR/ABL, in patients with Ph(+) CML. A review of the literature identified two different subtypes of malignant lymphomas arising in patients with an antecedent or concurrent diagnosis of CML. The most common are T cell lymphomas displaying an immature thymic phenotype, while peripheral B cell lymphomas are more rare. Our study shows, however, that 'Ph(+) NHL' occurring in CML or acute lymphocytic leukemia (ALL) may represent an unrelated neoplasm, even if standard cytogenetic analysis reveals a Ph(+) chromosome, and that FISH is required to confirm whether a localized lymphoid neoplasm is either a true extramedullary localized blast crisis or genetically distinct neoplasm. Leukemia(2000) 14, 169-182.

Detection of t(14; 18)(q32;q21) in hyperdiploid cells by fluorescence in situ hybridization in a patient with Hodgkin disease.

The most frequent nonrandom chromosome rearrangements in B-cell non-Hodgkin lymphoma (NHL) is the t(14;18)(q32;q21) found in follicular lymphomas. The t(14;18) in Hodgkin disease (HD) was rarely observed using cytogenetic techniques. Although Southern blot analysis failed to demonstrate the t(14;18), there have been conflicting reports concerning the occurrence of the translocation using polymerase chain reaction (PCR) methods in HD. In some HD tissues, the translocation might be derived from background lymphocytes rather than Hodgkin and Reed-Sternberg (HRS) cells, because B-cells with t(14;18) are regularly generated in normal individuals. However, the cells bearing the translocation have remained unidentified. We describe a patient with HD who showed t(14;18) in hyperdiploid cells using fluorescence in situ hybridization (FISH) and HRS cells which were strongly positive for BCL2 by immunohistochemistry. These findings suggest that HRS cells may have a t(14;18).

The Ikaros gene, a central regulator of lymphoid differentiation, fuses to the BCL6 gene as a result of t(3;7)(q27;p12) translocation in a patient with diffuse large B-cell lymphoma.

The BCL6 gene, isolated from the breakpoints of 3q27-associated chromosomal translocations, has been implicated in diffuse large B-cell lymphomas (DLBL). Here we describe the molecular characterization of novel t(3;7)(q27;p12) translocations in 2 patients with DLBL. Molecular genetic analysis of the breakpoint area involving BCL6 revealed the presence of the Ikaros gene, a central regulator of lymphoid differentiation that had been mapped to human chromosome 7 band p13-p11.1. As a molecular consequence of the translocation, the 5' regulatory region of the BCL6 gene was replaced by the putative 5' regulatory region of the Ikaros gene, probably leading to deregulated expression of the BCL6 gene throughout B-cell differentiation. Reverse transcription-polymerase chain reaction (RT-PCR) and fluorescence in situ hybridization (FISH) analyses of a patient sample established that the t(3;7)(q27;p12) results in fusion of the Ikaros and BCL6 genes. This study provides the first evidence that the Ikaros gene is rearranged in human hematopoietic malignant disorders. (Blood. 2000;95:2719-2721)

Influence of p53 mutation on pathological grade, but not prognosis of non-Hodgkin's lymphoma.

Mutations in the p53 gene were detected in 27 of the 107 (25%) cases of non-Hodgkin's lymphoma (NHL), examined by assaying the transcriptional activity of p53 in yeast. A relatively high mutation rate of p53 was observed in B-cell intermediate-grade NHL and in T-cell high-grade immunoblastic NHL, in contrast to the relatively low mutation rate observed in other pathological classifications. However, retrospective analyses of all 76 cases revealed that the survival profile and therapeutic responses were very similar in NHL patients bearing lymphomas with a mutant p53 or with the wild-type p53 even within the subclasses characterized by frequent p53 mutation. In patients with high-intermediate grade tumors, the median survival period was 24 months in mutated p53 cases and 14 months in wild-type cases. Complete remission (CR) was observed in 9 of the 17 patients (53%) with mutated forms of p53 and 18 of the 35 patients (51%) with wild-type p53 genes. Our analyses of NHL patients revealed that the presence of p53 mutations may influence pathological grades of NHL, but did not strongly correlate with poor prognosis or reduced chemo/radiosensitivity in NHL. Hence, mutations of p53 do not serve as a prognostic, or chemo/radiosensitivity marker in NHL.