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111.
McAlhany SJ Ressler SJ Larsen M Tuxhorn JA Yang F Dang TD Rowley DR 《Cancer research》2003,63(18):5859-5865
Human prostate cancer is associated with a reactive stroma typified by an increase in the proportion of myofibroblast type cells and elevated synthesis of extracellular matrix proteins. Increased vascular density has been identified in the reactive stroma compartment adjacent to both precancerous and cancerous prostate lesions. The differential reactive stroma (DRS) prostate cancer xenograft model has been developed to investigate the role of reactive stroma in prostate cancer progression. Using this model, we have shown that human prostate stromal cells promote angiogenesis and growth of LNCaP human prostate carcinoma cell tumors, and that these increases are transforming growth factor (TGF) beta1 regulated. Our laboratory isolated and identified previously the ps20 protein (WFDC1 gene) as a prostate stromal cell secreted protein. The ps20 protein contains a whey acidic protein-type four-disulfide core domain, which is a functional motif characterized by serine protease inhibition activity in a number of whey acidic protein domain-containing proteins. In the present study, we show ps20 expression by normal human prostate stromal smooth muscle cells and vascular smooth muscle cells indicating a possible role of ps20 in vessel wall biology. Using in vitro assays, we show that ps20 promotes endothelial cell motility but has no effect on endothelial cell proliferation. To address the potential effects of ps20 in a tumor microenvironment, we used the DRS model to evaluate both angiogenesis and tumorigenesis of tumors generated under either ps20 or control conditions. DRS tumors generated with LNCaP and human prostate stromal cells in the presence of ps20 showed a 67% increase in microvessel density compared with control tumors. Elevated DRS tumor growth in the ps20-treated tumors was reflected by a 29% increase in wet weight and a 58% increase in volume compared with controls. Similar tumors composed of GeneSwitch-3T3 cells engineered to express ps20-V5-His under mifepristone regulation showed a 129% increase in microvessel density after induction of ps20-V5-His. GeneSwitch-3T3 cells expressing ps20-V5-His were localized to vessel walls in a mural cell (pericyte) position indicating a possible direct stabilizing interaction with endothelial cells. In addition, we show that ps20 mRNA synthesis is induced by TGF-beta1, a known regulator of endothelial cell-pericyte interactions and of stromal cell-induced angiogenesis in DRS tumors. These findings suggest that ps20 may be a TGF-beta1-induced regulator of angiogenesis that functions by either promoting endothelial cell migration or by contributing to pericyte stabilization of newly formed vascular structures. 相似文献
112.
Truong AT Mulders MN Gautam DC Ammerlaan W de Swart RL King CC Osterhaus AD Muller CP 《Virus research》2001,76(1):71-78
In many parts of Asia measles virus (MV) continues to be endemic. However, little is known about the genetic characteristics of viruses circulating on this continent. This study reports the molecular epidemiological analysis based on the entire nucleocapsid (N) and hemagglutinin (H) genes of the first isolates from Nepal and Taiwan, as well as of recent MV strains from India, Indonesia, and China. Four isolates collected in various regions in Nepal during 1999 belonged to a new genotype, tentatively called D8. Another Nepalese isolate and one from India belonged to genotype D4. The diversity of the Nepalese strains indicated that measles continues to be endemic in this country. The isolate from Taiwan grouped with D3 viruses and one Chinese strain isolated in The Netherlands was assigned to the previously described clade H, known to be endemic in Mainland China. Molecular characterization emerges as an important tool for monitoring virus endemicity and vaccination efforts. 相似文献
113.
Montecino-Rodriguez E Truong LT Henderson AJ 《Journal of hematotherapy & stem cell research》2001,10(1):107-114
Long-term bone marrow cultures provide defined systems for studying and manipulating hematopoietic progenitors. Myeloid bone marrow cultures harbor early lymphoid progenitors; however, the nature and phenotype of these progenitors has not been investigated. Phenotypic and molecular markers associated with lymphopoiesis were used to characterize the lymphoid population maintained in these cultures. Cells within myeloid cultures expressed genes associated with lymphopoiesis but did not express the B cell-specific lambda5 gene. Flow cytometry demonstrated that cultures lacked cells expressing markers associated with B cell development. Furthermore, rearrangements of immunoglobulin heavy chain diversity (D) and joining (J(H)) gene segments were not detected in the myeloid cultures suggesting that these conditions support early B cell progenitors. Transferring myeloid cultures to conditions optimal for lymphopoiesis resulted in B cell development that temporally recapitulated events in the bone marrow. We also demonstrate that these lymphoid progenitors are targets for retroviral transduction. This study suggests that long-term cultures provide a useful system to access early lymphoid progenitors and study the events that regulate their differentiation. 相似文献
114.
Using data from the Add Health Study, the first nationally representative study of adolescents in the U.S. to include information on same-sex romantic attraction, we examine school outcomes (school troubles, attitudes, and performance) of same-sex attracted youth within the context of four relational domains: family, teacher, social, and peer. Results indicate that each domain plays a role in the negative attitudes about school held by these sexual minority youth. However, sexual minority youths' feelings about their teachers play an important role in explaining school troubles. 相似文献
115.
116.
Oh Y Perez-Soler R Fossella FV Glisson BS Kurie J Walsh GL Truong M Shin DM 《Investigational new drugs》2000,18(3):243-245
Twenty-four patients with pleural mesotheliomareceived 50 mg/m2 of Doxil® every four weeks.At follow-up, the disease had stabilized in 43% percent ofpatients and had progressed in 57%. No objective responses wereobserved. Estimated median survival of all patients was 37 weeks.Major toxicities were erythrodysesthesia of hands and feet andmyelosuppression. No cardiac toxicity was observed. We concludedthat Doxil® at this dosage and schedule is inactiveagainst pleural mesothelioma. 相似文献
117.
Yimin Ge Mario A. Luna Daniel F. Cowan Luan D. Truong Alberto G. Ayala 《Annals of diagnostic pathology》2009,13(6):384-389
Because thyrolipoma (adenolipoma of thyroid) and thyrolipomatosis (diffuse lipomatosis of thyroid) are distinctively rare conditions with only few cases reported in the literature, we are reporting 5 additional cases. All the 5 patients were adult females, with ages from 38 to 79 years, who presented with thyroid masses. Four of the patients had normal thyroid function tests and one had mild hypothyroidism. All patients received partial or total thyroidectomy. The thyroid specimens showed either circumscribed yellow-tan masses (cases 1, 2, and 3) or diffuse yellow-brown discoloration (cases 4 and 5). Histologic examination revealed abundant mature fat infiltrating the affected thyroid tissue in 3 distinct patterns: (1) fat infiltration limited to follicular adenomas (thyrolipoma); (2) fat diffusely infiltrating throughout the thyroid gland (thyrolipomatosis); or (3) fat infiltration involving both follicular adenoma and their surrounding thyroid tissue. Because of the rarity of thyroid fat-containing lesions, confusion in differential diagnosis may occasionally occur. It is important to be aware during frozen section that these lesions may present as extrathyroidal nodules, which can be radioactive on intraoperative scan for parathyroid glands. In addition, a papillary thyroid carcinoma was also identified in one case of thyrolipomatosis. All patients recovered well after surgery and there has been no recurrence of the lesions after 1 to 24 years of clinical follow-up. In summary, we are reporting 5 rare cases of thyrolipoma and thyrolipomatosis with distinct histologic patterns. Previously reported cases of thyrolipomatosis were reviewed and analyzed with the current cases. 相似文献
118.
Justin Bubola Klieb Hagen Nick Blanas Ilan Weinreb Brendan C. Dickson Tra Truong 《Head and neck pathology》2021,15(1):319
Ectomesenchymal chondromyxoid tumor is a rare neoplasm of uncertain histogenesis that typically occurs in the anterior dorsal tongue. Recent reports in the literature have described rare examples of gingival, palatal and tonsillar lesions. Histologically, ectomesenchymal chondromyxoid tumors are typically well-circumscribed, lacking overtly aggressive features. Herein we report a tumor arising in the right mandible that is morphologically and molecularly consistent with ectomesenchymal chondromyxoid tumor. This case furthers awareness of the extra-glossal distribution of this neoplasm; moreover, it suggests that a subset of these tumors have the potential for locally aggressive behaviour.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01169-5) contains supplementary material, which is available to authorized users. 相似文献
119.
To study the importance of prostatic involvement by transitional cell carcinoma (TCC) in patients with bladder cancer, we examined the entire prostates by whole-mount sections from 214 radical cystoprostatectomy specimens for detailed patterns of involvement by TCC and correlated the results with lymph node metastasis and patients' survival. Prostatic involvement by TCC was detected in 69 (32%) of 214 cases. Among them, 30 (43%) patients had carcinoma in situ (CIS) and the other 39 (57%) were invasive TCC. Carcinoma in situ occurred in either prostatic urethra (n = 6, 20%) or, more commonly, in prostatic ducts/acini (n = 14, 47%), and in a combination of prostatic urethra and ducts (n = 10, 33%). Ten (26%) of the invasive TCC resulted from direct penetration from the primary tumor in the bladder, and the remaining 29 (72%) cases arose from prostatic urethra/ducts, of which 11, 13, and 5 invaded the lamina propria, prostatic stroma, and periprostatic or seminal vesical tissue, respectively. Both prostatic TCC involvement and nodal metastasis were highly significant prognostic factors for patients' survival and the survival significance of prostatic TCC involvement still existed regardless of lymph node status. Furthermore, the presence of prostatic CIS and degrees of prostatic invasion are associated with nodal metastasis and survival. Patients with prostatic CIS or urethral lamina propria invasion had a similar, but higher incidence of lymph node metastasis and lower long-term and 5-year survival than those patients without prostatic involvement. Similarly, prostatic stromal invasion and periprostatic/seminal vesical invasion had a similar, but much higher nodal metastasis and worse survival than patients with only prostatic CIS or urethral lamina propria invasion. In summary, presence of prostatic TCC involvement and levels of involvement are significant prognostic factors in patients with bladder cancer. 相似文献
120.