Adult-derived stem cells from the liver become myocytes in the heart in vivo.

Recent evidence suggests that adult-derived stem cells, like their embryonic counterparts, are pluripotent. These simple, undifferentiated and uncommitted cells are able to respond to signals from their host tissue microenvironment and differentiate, producing progeny that display a phenotype characteristic of the mature cells of that tissue. We used a clonal stem cell line (termed WB-F344) that was derived from an adult male rat liver to investigate the possibility that uncommitted stem cells from a nonmyogenic tissue source would respond to the tissue microenvironment of the heart in vivo and differentiate into cardiac myocytes. Male WB-F344 cells that carry the Escherichia coli beta-galactosidase gene were identified in the left ventricular myocardium of adult female nude mice 6 weeks after transplantation. We confirmed the presence of a rat Y-chromosome-specific repetitive DNA sequence exclusively in the beta-galactosidase-positive myocytes by polymerase chain reaction and fluorescence in situ hybridization. Immunohistochemistry, using a cardiac troponin T-specific monoclonal antibody, and ultrastructural analysis confirmed a cardiac myocyte phenotype of the stem cell-derived myocytes. The beta-galactosidase-positive myocytes ranged from < 20 microm to 110 microm in length. The longer of these cells contained well-organized sarcomeres and myofibrils, and formed intercalated disks and gap junctions with endogenous (host-derived) myocytes, suggesting that WB-F344-derived myocytes participate in the function of the cardiac syncytium. These results demonstrate that adult liver-derived stem cells respond to the tissue microenvironment of the adult heart in vivo and differentiate into mature cardiac myocytes.

Down-regulation of HP1Hsalpha expression is associated with the metastatic phenotype in breast cancer.

We previously identified a down-regulation in heterochromatin-associated protein 1 (HP1)Hsalpha expression in MDA-MB-231 breast carcinoma cells (highly invasive/metastatic) compared with MCF-7 cells (poorly invasive/nonmetastatic). In this study, we demonstrate that HP1Hsalpha, but not HP1Hsbeta or HP1Hsgamma, is down-regulated at the mRNA and protein levels in highly invasive/metastatic breast cancer cell lines. In agreement, little to no nuclear HP1Hsalpha staining was observed in these cell lines. In contrast, poorly invasive/nonmetastatic cell lines showed HP1Hsalpha localization to the nucleus and nuclear membrane. Transfection of MDA-MB-231 cells with a green fluorescent protein-HP1Hsalpha expression vector decreased their ability to invade a collagen IV/laminin/gelatin matrix compared with green fluorescent protein-transfected controls. Consistent with the cell culture studies, immunohistochemical analysis of HP1Hsalpha protein localization in distant metastatic tissues from breast cancer patients revealed a decrease in the staining intensity and percentage of cells expressing HP1Hsalpha in seven of nine distant metastatic lesions compared with normal mammary and primary tumors. These results demonstrate a role for HP1Hsalpha in breast cancer invasion and metastasis. Given the role of HP1 in transcriptional silencing in Drosophila, we propose a model in which HP1Hsalpha normally silences genes involved in breast cancer invasion and metastasis.

Ovarian capillary hemangioma presenting as an adnexal mass with massive ascites and elevated CA-125.

OBJECTIVE: Ovarian hemangiomas are very rare with the majority being cavernous hemangiomas. We report a case of a capillary ovarian hemangioma. METHODS: A case report of a woman with a capillary ovarian hemangioma with massive ascites and an elevated CA-125 is presented. RESULTS: A 39-year-old woman presented with an enlarged ovary containing two ovarian cysts. Her CA-125 was elevated to 872 U/ml. On surgical exploration, she had 1500 cc of clear yellow ascitic fluid and a 7.9 x 6.5 x 4.5 cm left ovarian mass. Frozen section revealed marked stromal edema with luteinized cells and no evidence of malignancy. Histologically, the tumor was a cellular capillary hemangioma with an anastomosing vascular pattern. CONCLUSIONS: This is the first case, reported in the literature, of an ovarian capillary hemangioma presenting with an elevated CA-125 and massive ascites.

Use of keratin 35betaE12 as an adjunct in the diagnosis of mammary intraepithelial neoplasia-ductal type--benign and malignant intraductal proliferations.

A variety of studies have investigated the role of low molecular weight (LMW) and high molecular weight (HMW) cytokeratin (CK) expression in the normal breast and invasive breast carcinomas. A few studies with small numbers of cases have addressed this issue in intraductal proliferations of the breast. This study investigates the expression of these CKs in a large series of ductal intraepithelial neoplasias of the breast. We examined 150 ductal carcinomas in situ (DCIS), 35 cases of intraductal hyperplasia (IDH), and 15 cases of atypical intraductal hyperplasia (AIDH). Immunohistochemistry was performed using monoclonal antibodies against CK-34betaE12 (HMW CK), CK-8, and CK-19 (LMW CK) on formalin-fixed, paraffin-embedded tissue. The intensity (0, +1, +2, +3) and percentage of positive intraductal cells (0-100%) were multiplied to obtain a score from 0 to 300. The immunoprofiles of IDH, AIDH, and DCIS were categorized into four groups showing negative or low (0-60), moderate (61-100), high (101-200), and very high (201-300) scores. All cases of IDH showed an intensely positive reaction (high to very high scores) for CK-34betaE12. In contrast, 90% of the DCIS showed a negative or only focal and weak reaction (negative or low score) for this antigen. The remaining 10% of DCIS showed a positive immunoreaction for CK-34betaE12 with moderate to high scores. All cases of florid IDH and 96% of cases of DCIS expressed CK-8 intensely with high to very high scores. Although CK-19 was strongly expressed in 97% of cases of IDH (high to very high scores), a very high score was also found in 80% of cases of DCIS that were positive for CK-19. Of the 15 AIDHs, 80% had a negative or only focal reaction (negative or low score) for CK-34betaE12 and the remaining 20% had a moderate to high score for this antigen. Although CK-8 was strongly positive in 87% of cases of AIDH (high to very high scores), only 53.5% of AIDHs showed intense positivity for CK-19. The present study clearly shows that the immunoprofile of IDH is different from DCIS as far as HMW CK is concerned. Although florid IDH is characterized by a diffuse and intense immunoreaction for HMW CK, the lack of or only weak positivity for HMW CK (CK-34betaE12) is, in most cases, a hallmark of ductal carcinoma in situ. The immunoprofile of AIDH is very similar to that of DCIS. The expression of CK-8 and CK-19 is not useful in separating the various categories of ductal intraepithelial proliferations of the breast. We recommend the use of CK-34betaE12 as an adjunct in the diagnosis of a variety of problematic intraductal proliferations of the breast.

Loss of heterozygosity is detected at chromosomes 1p35-36 (NB), 3p25 (VHL), 16p13 (TSC2/PKD1), and 17p13 (TP53) in microdissected apocrine carcinomas of the breast.

INTRODUCTION: Apocrine carcinomas of the breast are an unusual special category of predominantly AR+, ER-, and PR- breast cancer, characterized by cells with abundant, eosinophilic cytoplasm and nuclei with often prominent nucleoli. To further investigate these lesions, loss of heterozygosity (LOH) was evaluated at multiple chromosomal loci, including loci frequently mutated in breast cancer. MATERIALS AND METHODS: Twenty-five intraductal apocrine carcinomas, 11 invasive apocrine carcinomas, and six apocrine hyperplasias were retrieved from the files of the Armed Forces Institute of Pathology (Washington, DC) and Fairfax Hospital (Fairfax, VA). Cells from lesional as well as normal tissues were microdissected. LOH was performed at a number of chromosomal loci, including loci commonly altered in breast cancer: 1p35-36 (NB), 3p25.5 (VHL), 8p12 (D8S136), 9p21 (p16), 11p13 (D11S904), 11q13 (INT-2 and PYGM), 16p13.3 (TSC2/PKD1 gene region), 17p13 (TP53), 17q13 (NM23), and 22q12 (D22S683). RESULTS: Among informative in situ and invasive apocrine carcinomas, LOH was present in 33% of 15 cases for 17p13 (TP53), as well as 36% of 14 cases for 3p25 (VHL), 30% of 10 cases for 1p35-36 (NB), and 27% of 11 cases for 16p13.3 (TSC2/PKD1). A higher frequency of LOH was noted among invasive apocrine carcinomas (30 to 50%) compared with in situ apocrine carcinomas (23 to 33%) at these loci. LOH was present simultaneously for TP53 and either VHL or NB in five cases. Infrequent (< or =12%) or absent LOH was detected at the remaining loci, including several loci commonly mutated in breast cancer (i.e., INT2, PYGM, and NM23). LOH was not detected in any of the six apocrine hyperplasias. CONCLUSION: An intermediate frequency of allelic loss was detected at multiple tumor suppressor gene loci, including 17p13 (TP53), as well as 1p35-336 (NB), 3p25 (VHL), and 16p13 (PKD1/ TSC2), in apocrine carcinomas of the breast, with a higher overall frequency of LOH noted among invasive tumors compared with in situ tumors. Aside from LOH at p53, LOH was infrequent or absent at several other loci commonly mutated in breast cancer. This preliminary molecular evidence supports immunohistochemical data that apocrine carcinomas of the breast may possess unique mechanisms of carcinogenesis, compared with ordinary ductal carcinomas. However, further study is needed to support this assertion and to determine if the LOH detected is truly etiologic or if it is the result of genetic progression.

Ductal carcinoma in situ (DCIS) in the male breast: a morphologic study of 84 cases of pure DCIS and 30 cases of DCIS associated with invasive carcinoma--a preliminary report.

BACKGROUND: Ductal carcinoma in situ (DCIS) in the male breast is a rare disease that to the authors' knowledge has been investigated to date only in small numbers. Compared with DCIS in the female breast, distinct clinical and morphologic differences have been suggested. METHODS: The files of the Armed Forces Institute of Pathology (AFIP) were searched for cases of pure DCIS and DCIS associated with invasive carcinoma (DCISAIC) in male patients. A total of 280 cases of pure DCIS and 759 invasive mammary tumors were identified; 114 cases (including 84 pure DCIS and 30 DCISAIC) were studied for this preliminary report. All cases were reviewed and classified according to specific subtypes (papillary, cribriform, solid, micropapillary, and comedo) and grades of DCIS. Basic clinical data were extracted from the patients' charts. RESULTS: Men with pure DCIS presented at a median age of 65 years, with a typically nodular, retroareolar, partially cystic mass that frequently was associated with a nipple discharge. The median duration of symptoms was 2 months for patients with pure DCIS and 6 months for patients with DCISAIC. Histologically, the predominant appearance of DCIS (in 74% of cases) was that of a papillary carcinoma often with a superimposed cribriform pattern. Intraductal extension beyond the main papillary lesion was common. It is interesting to note that the pure DCIS cases in this series were uniformly of either low or intermediate grade; high grade or comedocarcinomas were only observed within the group of DCISAIC. No significant morphologic differences between pure DCIS and DCISAIC were encountered, although DCISAIC did show relatively more cellular atypia with more frequent necrosis compared with pure DCIS. CONCLUSIONS: DCIS in the male breast is a distinct lesion that occurs at an older age and displays a significantly different distribution of morphologic subtypes compared with its female counterpart. It presents most frequently as an intraductal papillary carcinoma, and less commonly as a nonpapillary cribriform, solid, or micropapillary DCIS. In the current study the majority of pure DCIS cases were low grade (AFIP Grade 1) with occasional cases displaying necrosis (AFIP Grade 2); high grade pure DCIS appears to be a rare lesion in the male breast. In contrast, DCIS associated with invasive carcinoma more frequently is of higher grade.

LOH at 16p13 is a novel chromosomal alteration detected in benign and malignant microdissected papillary neoplasms of the breast.

Papillary carcinoma of the breast is a variant of predominantly intraductal carcinoma characterized by a papillary growth pattern with fibrovascular support. Loss of heterozygosity (LOH) was evaluated at multiple chromosomal loci (including loci reported to show frequent genetic alterations in breast cancer) to determine the frequency of genetic mutations in these tumors and their precursors. Thirty-three papillary lesions of the breast (6 papillary carcinomas, 12 carcinomas arising in a papilloma, and 15 intraductal papillomas with florid epithelial hyperplasia) were retrieved from the files of the Armed Forces Institute of Pathology (AFIP). Tumor cells and normal tissue were microdissected in each case and screened for LOH at INT-2 and p53 as well as several loci on chromosome 16p13 in the TSC2/PKD1 gene region (D16S423, D16S663, D16S665). LOH on chromosome 16p13 was present in 10 of 16 (63%) informative cases of either papillary carcinoma or carcinoma arising in a papilloma as well as in 6 of 10 (60%) informative cases of intraductal papilloma with florid epithelial hyperplasia (IDH). One case showed simultaneous LOH in both the florid IDH and carcinoma components of a papilloma. LOH was not observed at either INT-2 or p53 in any of the papillary carcinomas or papillomas with florid IDH. In conclusion, a high frequency of LOH at chromosome 16p13 (the TSC2/PKD1 gene region) is in both papillary carcinomas of the breast as well as in papillomas with florid IDH, including a case with LOH present simultaneously in both components. These findings suggest that chromosome 16p contains a tumor suppressor gene that frequently is mutated early in papillary neoplasia.

Human papillomavirus type 16 is detected in transitional cell carcinomas and squamotransitional cell carcinomas of the cervix and endometrium.

BACKGROUND: The etiologic role of human papillomavirus (HPV) in a variety of squamous neoplasms, including malignant and premalignant lesions of the cervix, is well established. The presence of HPV, predominantly HPV types 16 and 18, in adenocarcinomas of the endometrium has also been reported, although less commonly. Although rare, transitional cell carcinoma (TCC) in the female genital tract, including such sites as the cervix, endometrium, and ovary, has been described. HPV, however, has not been previously studied in TCC of the female genital tract, the etiology of which is uncertain. METHODS: Eight cases of primary TCC of the endometrium and six cases of primary TCC of the cervix were retrieved from the files of the Armed Forces Institute of Pathology and the University of Texas Southwestern Medical Center. Slides stained with hematoxylin and eosin were reviewed, and tumor tissue was obtained and analyzed for the presence of HPV types 6, 11, 16, 18, 31, and 33 by polymerase chain reaction (PCR). RESULTS: HPV was detected by PCR in 4 of 6 TCCs of the cervix (67%) and in 2 of 8 TCCs of the endometrium (25%), using HPV general primers and specific primers to HPV type 16. PCR for HPV using specific primers to HPV types 6 and 11, 18, 31, and 33 were negative in all cases. CONCLUSIONS: The results of this study demonstrated that HPV type 16 was present in a proportion of primary TCCs of the cervix and endometrium. These findings support the hypothesis that these rare neoplasms are similar, with regard to risk factors, to the more commonly occurring squamous cell carcinomas of the cervix, and suggest that HPV may play an etiologic role in at least a proportion of these tumors.

Comparison of loss heterozygosity in primary and recurrent ductal carcinoma in situ of the breast.

Ductal carcinoma in situ (DCIS) of the breast is often an indolent disease, although some cases are reported to recur many years after a limited surgical resection. It is not known whether these recurrences reflect a resurgence of residual disease or an independent development of a second tumor in susceptible individuals. Therefore, we conducted a longitudinal molecular study of four women with reappearance of DCIS 2 to 15 years after an initial conservative resection. Loss of heterozygosity (LOH) was characterized in both tumors in each case, using several polymerase chain reaction-amplified microsatellite markers on five chromosomal arms commonly affected in breast cancer. In three cases with ipsilateral recurrent disease, all of the allelic losses seen in the initial tumors were also seen in the recurrent lesions, suggesting a common genetic pathway for the development of both lesions and continuous proliferation of residual disease. The presence of at least one additional LOH in all of the three recurrent tumors, however, suggests that the recurrent tumors developed after genetic progression. In contrast, in one case of DCIS that was followed by the development of DCIS in the contralateral breast 7 years later (a case of bilateral DCIS), unrelated LOH patterns were present in the two lesions. These findings suggest that the reappearance of DCIS in the same breast is most commonly the result of a tumor derived from (but not identical to) the original lesion, with acquisition of additional genetic changes, even when the recurrent lesion manifested itself many years (15 years, in one case) after the initial presentation. Furthermore, genetic progression could be detected in tumors recurring in as little as 2 years after the initial resection.

Transitional cell carcinoma of the endometrium and endometrial carcinoma with transitional cell differentiation.

BACKGROUND: Transitional cell carcinoma (TCC) is rare in the female genital tract. Although it is most common in the ovary, small series of cases in the cervix have been reported, with isolated cases described in the fallopian tube, adnexa uteri, and endometrium. METHODS: Eight cases of primary TCC involving the endometrium and 1 case of ovarian TCC metastatic to the endometrium were retrieved from the files of the Armed Forces Institute of Pathology and the University of Texas Southwestern Medical Center. Cases were selected based on the presence of endometrial TCC, whether pure or combined with other patterns, and regardless of the relative amount. Immunostaining for cytokeratins 7 and 20 was performed. RESULTS: Among the 8 women with primary endometrial tumors, the mean age was 61.6 years (range, 41-83 years). Uterine bleeding was the presenting symptom in 7 women. Macroscopically, the tumors were polypoid, and infiltrated the myometrium, although the extent of infiltration varied. Seven endometrial tumors showed a papillary component. TCC was always admixed with other patterns (predominantly squamous, but also endometrioid, papillary, and serous patterns), with the proportion of the TCC component ranging from 5% to 95% (mean, 63.8%). TCC was the main invasive pattern observed in all three of the cases that had deep myometrial invasion; these cases also had vascular invasion. Seven tumors were confined to the uterus; one was metastatic to the ovary. The ovarian TCC metastatic to the endometrium had a pure TCC pattern. Five of 7 cases of TCC had cytokeratin 7+/20- immunoreactivity; 2 cases were cytokeratin 7-/20-. Treatment of primary endometrial tumors was mainly surgical, with adjuvant radiation therapy in 4 cases or chemotherapy in 1 case. Survival ranged from 3 months to 12.9 years (mean, 5.1 years). Of five women for whom follow-up was available, three were alive with no evidence of disease, one was alive with a local recurrence, and one died of unrelated disease. CONCLUSIONS: TCC is a rare, distinct subtype of endometrial carcinoma with morphologic features of urothelial differentiation, but retention of a mullerian immunoprofile. While the overall prognosis does not appear to be worse than what might be anticipated for the stage of tumor present, TCC appears to be the more aggressive histologic subtype among the patterns with which it is admixed.

Identical clonality of both components of mammary carcinosarcoma with differential loss of heterozygosity.

The histogenesis of carcinosarcomas is controversial, specifically with respect to clonality and cell of origin. To answer these questions, tumor cells from both epithelial and spindle-cell components were microdissected from three cases each of mammary carcinosarcoma and its postulated precursor, carcinoma with spindle-cell metaplasia. Clonality was assessed using the principle of X chromosome inactivation. Loss of heterozygosity (LOH) was evaluated at seven chromosomal loci to assess shared and distinctive genetic alterations for the two components in each tumor. All of the six cases demonstrated identical clonality of the carcinomatous and spindle-cell components, identical to a focus of ductal carcinoma in situ present in one case. LOH for NM23 was detected in both components in one carcinosarcoma, whereas LOH for INT-2 was detected in both components in one metaplastic carcinoma. Differential LOH for D11S904 was present in only the mesenchymal components of these two cases. We conclude that the two components of carcinosarcoma and its precursor are clonal and that the sarcomatous and spindle-cell components arise from mutation of the carcinoma. Presence of differential LOH at D11S904 in only the spindle-cell components suggests that this mutation might be critical to the development of this second phenotype.

The pathology of vulvar neoplasia.

Current literature on the pathology of vulvar disease continues to focus on vulvar intraepithelial neoplasia, the role of human papillomavirus in vulvar neoplasia, and Paget's disease of the vulva. Of particular concern is an increasing incidence of vulvar intraepithelial neoplasia noted over the past several decades, specifically among younger women. Human papillomavirus has emerged as a major factor in this trend. Furthermore, a more aggressive course may ensue in these young women, requiring diligent follow-up.

Steroid hormones and risk of breast cancer.

BACKGROUND: More than three decades of epidemiologic studies have identified numerous risk factors for breast cancer. These factors have been estimated to account for only 20-25% of disease occurrence. However, among these factors, several are related to sex steroid hormones: sex of the affected individuals (women), early age of menarche and late age of menopause, parity, late age at first pregnancy, and obesity in postmenopausal women. METHODS: Theoretical models and laboratory data support hormonal mechanisms of carcinogenesis, particularly as they relate to proliferation of breast ductal epithelium and terminal end bud growth and differentiation in the lobules of the breast. The recent introduction of biologic markers and molecular epidemiology allows for studies that use laboratory technology in the context of epidemiologic research. RESULTS: This paper summarizes the epidemiologic literature on exogenous hormones, addresses the issue of endogenous steroid hormone levels and estrogen metabolism in serum and breast tissue in premenopausal and postmenopausal women with and without cancer, speaks to the cellular mechanisms of action of estrogen and progesterone, and highlights some of the biologic markers relevant to studies of breast cancer and precursor lesions, with particular emphasis on those that may be hormonally induced or altered. CONCLUSIONS: These markers must be better defined in terms of breast cancer pathogenesis. Studies are needed to evaluate the direct effects of behavioral/environmental risk factors on relevant biomarkers as well as to assess the interactions of epidemiologic factors and biomarkers on risk of breast cancer.