Delta N89 beta-catenin induces precocious development, differentiation, and neoplasia in mammary gland.

To investigate the role of beta-catenin in mammary gland development and neoplasia, we expressed a stabilized, transcriptionally active form of beta-catenin lacking the NH(2)-terminal 89 amino acids (Delta N 89 beta-catenin) under the control of the mouse mammary tumor virus long terminal repeat. Our results show that Delta N 89 beta-catenin induces precocious lobuloalveolar development and differentiation in the mammary glands of both male and female mice. Virgin Delta N 89 beta-catenin mammary glands resemble those found in wild-type (wt) pregnant mice and inappropriately express cyclin D1 mRNA. In contrast to wt mammary glands, which resume a virgin appearance after cessation of lactation, transgenic mammary glands involute to a midpregnant status. All transgenic females develop multiple aggressive adenocarcinomas early in life. Surprisingly, the Delta N89 beta-catenin phenotype differs from those elicited by overexpression of Wnt genes in this gland. In particular, Delta N 89 beta-catenin has no effect on ductal side branching. This suggests that Wnt induction of ductal branching involves additional downstream effectors or modulators.

Initiation of translation from a downstream in-frame AUG codon on BRCA1 can generate the novel isoform protein DeltaBRCA1(17aa).

Expression of the breast and ovarian cancer gene BRCA1 is regulated at both the transcriptional and post-transcriptional levels. We found that the expression of the BRCA1 protein may also be regulated at the translational level. In addition to an AUG start codon at position 1, BRCA1 mRNA has a second in-frame AUG (+17) that acts as an alternative start codon to generate a novel BRCA1 protein that lacks the first 17 amino acids (DeltaBRCA1(17aa)). We fused cDNAs encoding the second exon of BRCA1 of the wild-type BRCA1 gene (wt-BRCA1) and a mutated BRCA1 gene (mt-BRCA1), in which the first initiation site and its Kozak consensus sequence were abolished, with the nucleophosmin (NPM) reporter gene and used them for in vitro and in vivo translation assays. In both systems, the wt-BRCA1-NPM constructs produced two distinct proteins (18 and 16 kD) begun from the first and second AUGs. The mt-BRCA1-NPM constructs produced only the shorter 16-kD protein lacking the first 17 amino acids of the BRCA1 gene. Next, we analysed the N-terminal protein sequence of purified BRCA1 protein from normal thymocytes and found two different BRCA1 proteins, derived from translation of the first and second in-frame AUGs. Thus, BRCA1 protein expression can be regulated at the translation level in normal cells. Characterization of DeltaBRCA1(17aa) may shed light on the function and regulation of BRCA1 in normal cells as well as the pathogenesis of breast and ovarian cancers. Oncogene (2000).

Onset of glomerular hypertension with aging precedes injury in the spontaneously hypertensive rat.

The changes in renal hemodynamics that develop with aging in spontaneously hypertensive rats (SHR) were examined. Micropuncture studies revealed that glomerular capillary pressure was elevated in SHR at 9 mo of age compared with 3-mo-old SHR and 9-mo-old normotensive Wistar-Kyoto rats. Glomerular hypertension developed because of a small increase in systemic blood pressure and a decline in preglomerular vascular resistance, allowing transmission of elevated systemic pressure to the glomerular capillaries. The hemodynamic alterations were not a compensatory response to injury, inasmuch as vascular and glomerular morphology were normal in 9-mo-old SHR. To determine the mechanism of these changes, the activity of several vasoactive systems was examined. Similar changes in renal hemodynamics were observed in young and old SHR after blockade of nitric oxide production and after intravenous administration of endothelin. However, ANG II produced a proportionally greater reduction in glomerular filtration rate than renal blood flow in older SHR. These data suggest that reduced endogenous activity of the renin-angiotensin system leads to glomerular hypertension in aging SHR. Late development of glomerular hypertension may contribute to the subsequent appearance of glomerular sclerosis and progressive renal failure in these rats.

Multiplex genotype analysis of invasive carcinoma and accompanying proliferative lesions microdissected from breast tissue.

To understand the genetic basis of breast cancer in a comprehensive way, purported precursor lesions need to be analyzed at a large number of genetic marker loci and compared with each other and with the invasive components. However, the microscopic size of most of these lesions and the very small amount of material that can be obtained through microdissection limit the number of loci that can be included in the analysis. To address this issue, a multiplex genotyping approach has been developed. With this approach, polymorphic sequences at 28 marker loci were amplified simultaneously from the micro-dissected components in 5-microm paraffin-embedded breast tissue sections. The genotypes of the lesions were determined after resolving the amplified allelic products by denaturing gradient gel electrophoresis. Because the material isolated from each lesion in a single 5-microm section was sufficient for several 28-locus assays and several successive tissue sections with the same set of lesions may be prepared, it is possible to determine the genotype of each lesion at hundreds of genetic marker loci that may well cover the human genome. Analyzing a sufficient number of cases may yield information that could be used to understand the genetic basis of breast cancer development in a comprehensive way.

gamma-heregulin is the product of a chromosomal translocation fusing the DOC4 and HGL/NRG1 genes in the MDA-MB-175 breast cancer cell line.

gamma-heregulin is a recently described novel isoform of the heregulin/neuregulin class of EGF-like ligands that bind to and activate receptors of the ErbB family. Deregulated signaling through the heregulin-ErbB pathway is thought to be implicated in the development of a subset of human breast cancers. gamma-heregulin has been found to be expressed in the culture supernatant of MDA-MB-175, a breast carcinoma cell line. gamma-heregulin is characterized by the presence of a large N-terminal peptide extension that is not found in other heregulin isoforms. Here we report that this unique N-terminal extension of gamma-heregulin is identical to the N-terminus of DOC4, a product of a recently identified CHOP-dependent stress-induced gene. Human DOC4 and the heregulin-encoding genes map to different chromosomes and the MDA-MB-175 cell line contains a chromosomal translocation that leads to the fusion of DOC4 and HGL, on chromosomes 11 and 8, respectively. Thus, gamma-heregulin is a product of a mutant fusion gene and not a bona fide normal isoform. We speculate that the mutation may be selected for by virtue of its ability to activate ErbB signaling through the production of an autocrine ligand.

Lipid-rich follicular carcinoma of the thyroid in a patient with McCune-Albright syndrome.

A 41-year-old woman with McCune-Albright syndrome and a 2-cm thyroid nodule of ten years' duration presented for fine-needle aspiration, which yielded vacuolated clear cells with granular chromatin in pseudopapillary arrangement. The resected tumor showed 90% clear cells and 10% nonclear cells with capsular and vascular invasion. The cytoplasmic vacuoles in the clear cells were 3+ for oil red O stain in touch imprint cytology. Immunohistochemistry demonstrated thyroglobulin positivity in the nonclear neoplastic cells, whereas most of the clear cells were negative. Ultrastructural study demonstrated the gradual transition from protein synthesis to lipid synthesis as the neoplastic cells progressed from nonclear to clear. The study suggested that the lipid accumulation resulted from the uncontrolled fatty acid synthesis in the neoplastic cells rather than metaplasia. The karyotype of the tumor cells was normal, 46XX. Literature of lipid-rich thyroid neoplasms were reviewed.

Tubular carcinoma of the breast: sensitivity of diagnostic techniques and correlation with histopathology.

OBJECTIVE: Our objective was to assess our experience in diagnosing pure tubular carcinoma of the breast and to correlate the radiologic and histopathologic features. MATERIALS AND METHODS: A retrospective review of 932 consecutive cases of proven breast cancer diagnosed between 1990 and 1997 revealed 78 cases (8.4%) of tubular carcinoma in 69 patients. Clinical, imaging, cytologic, and histologic findings were analyzed. RESULTS: Mammography revealed tubular carcinoma in 68 (87%) of the 78 cases. Sonography showed tubular carcinoma in all 38 cases in which it was used; nine of these lesions were mammographically occult. These nine lesions were slightly, but not significantly (p < .05), smaller than the 29 lesions that had also been detected on mammography. Large core needle biopsy was performed in 22 patients (sensitivity, 91%). At biopsy, diagnoses were malignant (n = 16 [73%]), suspicious (n = 4 [18%]), atypia (n = 1 [4.5%]), and benign (n = 1 [4.5%]). Fine-needle aspiration biopsy was used to evaluate 36 cases of tubular carcinoma (sensitivity, 50%); cytologic diagnoses were malignant (n = 15 [42%]), suspicious (n = 3 [8%]), atypia (n = 10 [28%]), and benign (n = 8 [22%]). Only 15 (19%) of the 78 tubular carcinomas were palpable. Other tumors were detected within the excised tissue in 47 of the patients (68%); of these other types of lesions, ductal carcinoma in situ was found most often. CONCLUSION: Most cases of tubular carcinoma can be revealed by mammography; for mammographically occult tubular carcinoma, sonography can be performed. The rate of accuracy for determining the presence of tubular carcinoma is higher with large core needle biopsy than with fine-needle aspiration biopsy. Finally, when tubular carcinoma is diagnosed, other histologic types of carcinoma often occur in the same breast.

Repression of interleukin-2 mRNA translation in primary human breast carcinoma tumor-infiltrating lymphocytes.

Human breast carcinoma tumor-infiltrating lymphocytes (TIL) express activation antigens in situ indicative of ongoing immune response-CD28, CD45RO, CD69, CD71, and DR. However, interleukin 2 (IL-2) receptor was poorly expressed: CD25 was detected in only 1/24 samples and CD122 in only 2/24 samples. Furthermore, isolated breast cancer TIL were defective in proliferative response but recover when treated with recombinant IL-2. Nineteen of 24 tumor samples expressed B7-1, B7-2, and CD28 protein, showing that absence of costimulator proteins or counter ligand was not the basis for TIL proliferative deficit. Expression of IL-2 activity was not detected; however, mRNA encoding IL-2 was produced and translatable in vitro. These findings show that human breast cancer tumor-induced repression of IL-2 RNA translation is the basis of failure of TIL to express the IL-2 receptor and subsequent T cell hyporesponsiveness.

Numerical abnormalities of chromosomes 7, 18, and x in precancerous breast disease defined by fluorescent in situ hybridization.

Nonrandom numerical chromosomal abnormalities (NCA) are frequent in invasive breast cancer, but little is known about such changes in microscopic precursor lesions. Mammographically detected "suspicious" breast lesions were localized by specimen radiology of sliced breast tissue. The slices containing the lesion were imprinted onto coated slides by gentle scraping. The corresponding hematoxylin and eosin stained histologic sections and Diff-Quik stained imprints were used for classification as ductal hyperplasia (DH), atypical ductal hyperplasia (ADH), and ductal carcinoma in situ (DCIS). Additional slide imprints were evaluated for copy number of chromosomes 7, 18, and X by using fluorescent in situ hybridization with alpha satellite probes. NCA were detected in 1 of 9 (11%) cases of DH, in 2 of 8 (25%) cases of ADH, and in 14 of 16 (87%) cases of DCIS. There was selective loss (chromosome 18) in one case of DCIS; all other cases with NCA had a gain of at least one chromosome. There is a progressive increase in incidence of NCA in DH, ADH and DCIS. The majority of NCA are chromosomal gains.

Morphological and biological characteristics of mammogram-detected invasive breast cancer.

Thirty-nine mammographically detected, (M-detected) small invasive carcinomas of the breast (< or = 5 mm) were compared with 78 consecutive clinical cancers (> or = 10 mm) for a variety of morphological and biological markers of prognostic importance. There were more tubular carcinomas in the M-detected group (12.8% v 3.8%), but this did not reach statistical significance. Incidences of other histological types were similar. The types of associated in situ component were similar in the two groups. M-detected cancers were of lower overall grade (P < .001), lower architectural and nuclear grades (P = .0164 and P < .0001 respectively), and had fewer mitotic cells (P < .0001). None showed positive lymph nodes (P < .0001). Estrogen and progesterone receptor expression was similar in both groups. M-detected cancers expressed p53 nuclear protein less frequently than clinical cancers (P = .0398), had lower levels of microvessel density (P = .0001), and were more often diploid (P = .0131). S-phase of diploid tumors in the two groups was similar, but S-phase of aneuploid tumors was lower in the M-detected group (P = .0057). Ki67 expression was lower in M-detected cancers (P < .0001). In conclusion, M-detected small breast cancers, although invasive, represent an evolutionary phase of breast cancer that generally lacks morphological and biologic markers of aggressive behavior. The presence or absence of these markers, collectively, may explain the influence of tumor size on survival in patients with breast cancer.

Cytology of extranodal Ki-1 anaplastic large cell lymphoma.

Ki-1-positive anaplastic large-cell lymphoma (ALCL) is an uncommon neoplasm which may present with extranodal as well as nodal disease. By definition, the tumor cells are immunoreactive for Ki-1 or Ber-H2 antigen (CD30). There have been few published cytologic descriptions of this lymphoma, or of its detection in extranodal sites. We describe the cytologic findings in five cases of extranodal Ki-1 lymphoma. Cytologic findings in all five cases were similar and consisted of a heterogeneous population of lymphocytes and bizarre, pleomorphic tumor cells. These cells were characterized by generous amounts of vacuolated, basophilic cytoplasm, eccentric, multilobulated nuclei with some showing "wreath-like" configurations. Some nuclei contained huge nucleoli simulating Reed-Sternberg cells. All cases showed the characteristic surface membrane and cytoplasmic paranuclear dot-like staining for CD30. Our findings indicate that fine-needle aspiration and exfoliative cytology have a useful role in the diagnosis of Ki-1 ALCL in extranodal sites. Furthermore, effusions containing anaplastic cells suspicious for lymphoma, particularly in AIDS patients, should be immunostained with antibodies to CD30.

Salt restriction inhibits renal growth and stabilizes injury in rats with established renal disease.

Salt restriction inhibits renal growth and stabilizes injury in rats with established renal disease. Male Munich-Wistar rats that underwent right nephrectomy and segmental infarction of two thirds of the left kidney were fed standard chow for 4 wk and then randomly assigned to ingest standard or low-salt chow for an additional 4 wk. Four wk after ablation, rats had systemic hypertension, proteinuria, and glomerular sclerosis. The prevalence of sclerosis, protein excretion rate, and glomerular volume increased between the fourth and eighth week in rats that were fed standard chow, however, in rats that were fed low-salt chow, the increase in glomerular volume and development of further glomerular sclerosis was prevented whereas the protein excretion rate actually declined. Micropuncture studies performed 8 wk after ablation revealed that the glomerular hydraulic pressure was elevated in remnant kidneys and was not affected by salt restriction. This study demonstrates that dietary salt restriction can prevent further glomerular injury and reduce proteinuria even when instituted in rats with established renal disease. These findings are also consistent with the hypothesis that glomerular hypertrophy promotes injury in this model of hypertension and progressive renal disease.

Mammographically detected breast lesions: clinical importance of cytologic atypia in stereotaxic fine-needle aspiration biopsy samples.

PURPOSE: To correlate cytologic findings of stereotaxic fine-needle aspiration biopsy samples with histologic findings of excised samples of nonpalpable mammographically detected lesions. MATERIALS AND METHODS: In a retrospective review of 2,988 consecutive stereotaxic fine-needle aspiration biopsy samples of nonpalpable breast lesions obtained within 5 years, 70 samples were categorized as atypical. Excision with needle localization and specimen radiography were performed in all lesions; cytologic findings of aspirates were correlated with histologic findings of excised samples. Histologic findings were the standard of reference. RESULTS: Of the 70 atypical aspirates, 27 were benign (38%) and 43 were malignant (61%). Both the benign and the malignant lesions had an average size at mammography of 1.1 cm. The nuclear grade was low in 21 (49%), moderate in 16 (37%), and high in six (14%) of the malignant lesions. There were axillary lymph node metastases in four samples (9%). CONCLUSION: Although lesions with atypical aspirates usually are benign, to achieve a low prevalence of false-negative diagnoses atypia must be interpreted as potential malignancy.

Effects of amlodipine on glomerular filtration, growth, and injury in experimental hypertension.

The objective of this study was to determine whether the calcium antagonist amlodipine could slow the progression of chronic renal disease. We examined the effects of amlodipine on kidney structure and function in two experimental models of hypertension. In the first study, adult, male Munich Wistar rats underwent uninephrectomy and were given weekly injections of desoxycorticosterone and 1% saline for drinking. Rats ingested normal chow or chow containing amlodipine for 8 weeks. The drug reduced systemic blood pressure, but glomerular filtration rate, kidney weight, proteinuria, and morphological evidence of glomerular injury were not affected. In the second study, male spontaneously hypertensive rats underwent uninephrectomy at 5 weeks of age and were followed for 6 months, during which they received no therapy or amlodipine. The drug dose was determined in preliminary studies to be the highest dose not associated with marked growth retardation. Again, although systemic blood pressure was significantly reduced by amlodipine, proteinuria and the prevalence of glomerulosclerosis were similar in amlodipine-treated and control spontaneously hypertensive rats. Micropuncture studies revealed that glomerular pressure remained elevated in amlodipine-treated spontaneously hypertensive rats. Kidney weight and glomerular volume were also similar in amlodipine-treated and control rats. Amlodipine also failed to inhibit platelet aggregation. Therefore, antihypertensive therapy with amlodipine fails to reduce glomerular pressure in spontaneously hypertensive rats as well as glomerular size and injury in spontaneously hypertension rats and desoxycorticosterone-salt hypertension. Although other dihydropyridine calcium antagonists have been found to reduce experimental glomerular injury, these data suggest that amlodipine may not prevent hypertensive nephrosclerosis.

Mycosis fungoideslike T-cell cutaneous lymphoid infiltrates in patients with HIV infection.

Cutaneous patch and plaque lesions, and erythroderma may suggest mycosis fungoides both clinically and histopathologically in HIV+ patients. However, in some cases, this diagnosis is questionable. Five such cases are presented. When we compared these cases with cases of mycosis fungoides unassociated with HIV infection, we found less concordance among dermatopathologists in making a histopathological diagnosis, a greater proportion of CD8 than CD4 T cells in the cutaneous infiltrates, and no instances of demonstrated clonality of the cutaneous T-cell infiltrates in the HIV+ group. We conclude that CD8 T-cell predominant dermatoses may simulate mycosis fungoides in HIV+ patients.

Primary lymphomatous effusions in AIDS: a morphological, immunophenotypic, and molecular study.

Lymphomas were documented in pleural effusions or ascites in 18 human immunodeficiency virus-positive (HIV+) patients. Eleven of 12 with clinical data had acquired immunodeficiency syndrome before the diagnosis of lymphoma. In 13 of 15 with data available, a body cavity was the site of initial presentation of lymphoma. Cytological subtypes were large cell immunoblastic, n = 7; large cell anaplastic, n = 6; and large cell NOS, n = 5. The high incidence of anaplastic large cell lymphoma and the conspicuous absence of Burkitt's lymphoma differ strikingly from HIV-associated lymphomas generally. Immunophenotypically, two cases were B-cell (CD19/20+, sIg+, CD/5-), one was T-cell (CD3+, CD5+, CD4+, CD8-, CD19/20-, sIg-), and 15 were null (CD45+, HLA-DR+ CD19/20-, sIg-, CD3/5-). This 83% incidence of null immunophenotype contrasts sharply with a 9% incidence among 35 tissue-based lymphomas in HIV+ patients that were similarly studied and a 0% null immunophenotype among 11 lymphomatous effusions in patients without HIV risk factors. Seven of the 18 HIV-associated lymphomas expressed CD30. Four of five cases with null immunophenotype showed Ig heavy-chain gene rearrangement, two had clonal Epstein-Barr virus integration, and none had MYC protooncogene rearrangement. These cases belong to a subgroup of high-grade HIV-associated lymphomas that occur in the setting of profound immunosuppression in which immunoblastic morphology predominates and MYC rearrangement is encountered only infrequently.

Visceral leishmaniasis in the acquired immunodeficiency syndrome: report of two cases.

Core biopsies of the bone marrow are indispensable in the evaluation of fever of unknown etiology in human immunodeficiency virus-positive patients. We report two patients in whom visceral leishmaniasis was diagnosed based on the typical morphology, staining characteristics, and ultrastructure of the organisms.

Flow cytometric DNA ploidy and quantitative histopathology in partial moles.

This study quantitates morphologic changes seen in partial moles and hydropic abortuses in an attempt to find a correlation with DNA content. Thirty-two products of conception were studied. Fifteen were diagnosed as definitive partial moles (DPM), and 17 had changes suggestive of a partial mole (SPM). We determined DNA ploidy by flow cytometry and quantitatively analyzed the following microscopic features: villous edema and sclerosis, central cistern formation, villous blood vessels, trophoblastic proliferation, and trophoblastic inclusions. No single pathologic feature significantly correlated with DNA content, even though triploid cases showed more inclusions than diploid cases (8.3 versus 7.2 on the average per ten x 100 fields). An overall diagnosis of DPM did correlate with ploidy; 12 of 18 triploid cases (67%) compared with only three of 13 diploid cases (23%) had been previously diagnosed as DPM (p < 0.05). Flow cytometric DNA ploidy estimates DNA content and cannot determine chromosomal origin. It is possible that detailed cytogenetic studies of moles compared with abortuses may show a significant correlation of the proportion of paternal chromosomes, morphologic changes, and the risk of persistent gestational trophoblastic disease.

Immunophenotypic evaluation of the bone marrow in non-Hodgkin's lymphoma.

Immunophenotypic evaluations of the bone marrow (BM) are reported on 69 aspirates from 58 patients who had non-Hodgkin's lymphoma or chronic lymphocytic leukemia involving the BM. Using flow cytometry and immunofluorescence microscopy on density gradient isolated BM mononuclear cells, the neoplasm could be identified and characterized in 59 aspirates (86%) from 49 patients (84%). Using International Working Formulation guidelines the neoplasms were classified on the basis of prior or subsequent histopathology of lymph node, spleen, skin, or other soft tissue site, or by evaluation of peripheral blood in chronic lymphocytic leukemia. In nine cases the lymphoma could not be completely classified according to International Working Formulation guidelines because only BM was available for evaluation. The neoplasm in the BM was identified and characterized immunophenotypically in all 29 cases of chronic lymphocytic leukemia/well-differentiated lymphocytic lymphoma (WDLL) (100%), in 11 of 12 cases of low-grade lymphoma other than WDLL (92%), in 11 of 15 cases of intermediate-grade lymphoma (73%), and in two of four cases of high-grade lymphoma (50%). Six of the nine cases not classified by International Working Formulation guidelines could be characterized immunophenotypically. In 10 cases immunophenotypic studies revealed negative findings, although the concurrent core biopsy specimens were positive. In two cases immunophenotypic studies with positive findings accompanied a negative core biopsy specimen. A panel of immunohistochemical reagents reactive with fixative/paraffin-resistant antigens was used for a retrospective evaluation of the 69 core biopsy specimens. When compared with the immunophenotypic data obtained from the marrow aspirates these results proved to be only moderately reliable in B-lineage neoplasms and unreliable in T-cell neoplasms. Thus, immunophenotyping of aspirated marrow by flow cytometry was found to be the most reliable method for determining the antigenic profiles of BM-based lymphomas.