Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recently, we demonstrated that an androgen-regulated cell adhesion molecule, C-CAM, acts as a tumor suppressor in prostate cancer development. In this study, we further explored the possibility of applying C-CAM as a potential agent for developing prostate cancer gene therapy using an adenoviral delivery system. We found that prostate cancer cells, in general, were sensitive to adenoviral infection. In vitro characterization indicated that C-CAM1 protein was detected only in C-CAM1 adenovirus-infected cells but not in antisense control virus-infected cells, and the levels of expression showed dose dependency. Because of the stability of the protein, C-CAM expression in viral-infected cells appeared to be a long-lasting event, indicating that C-CAM may be superior to many other known tumor suppressors that have a short protein half-life. Most importantly, the delivery of a single dose of C-CAM adenovirus was able to repress the growth of PC-3-induced tumors in nude mice for at least 3 weeks. Taken together, these data indicate that C-CAM is a potential candidate for human prostate cancer therapy.
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PMID:Application of a tumor suppressor (C-CAM1)-expressing recombinant adenovirus in androgen-independent human prostate cancer therapy: a preclinical study. 779 10

We recently demonstrated that C-CAM, an epithelial-cell adhesion molecule of the immunoglobulin supergene family, could be regulated by androgen and might act as a growth repressor during differentiation of the prostatic epithelium. To define the role of C-CAM in prostatic tumorigenesis, a tumorigenic human prostatic cancer cell line, PC-3, was transfected with an expression plasmid containing C-CAM1 (a C-CAM isoform). Transfected clones showed significantly lower growth rates, reduced anchorage-independent growth, and less tumorigenicity in vivo than control cells. Furthermore, transfection of an antisense vector into a nontumorigenic prostatic epithelial cell line, NbE, resulted in tumor formation in nude mice. Sublines derived from these NbE-induced tumors had lower levels of C-CAM than did control cells. These data suggest that C-CAM1 can function as a tumor suppressor in prostate tumorigenesis.
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PMID:Tumor suppressive role of an androgen-regulated epithelial cell adhesion molecule (C-CAM) in prostate carcinoma cell revealed by sense and antisense approaches. 780 32

Using a monoclonal antibody, we have identified and characterized a previously unknown cell surface protein in chicken that we call neogenin and have determined its primary sequence. The deduced amino acid sequence and structure of neogenin characterize it as a member of the immunoglobulin (Ig) superfamily. Based on amino acid sequence similarities, neogenin is closely related to the human tumor suppressor molecule DCC (deleted in colorectal cancer). Neogenin and DCC define a subgroup of Ig superfamily proteins structurally distinct from other Ig molecules such as N-CAM, Ng-CAM, and Bravo/Nr-CAM. As revealed by antibody staining of tissue sections and Western blots, neogenin expression correlates with the onset of neuronal differentiation. Neogenin is also found on cells in the lower gastrointestinal tract of embryonic chickens. DCC has been observed in human neural tissues and has been shown to be essential for terminal differentiation of specific cell types in the adult human colon. These parallels suggest that neogenin, like DCC, is functionally involved in the transition from cell proliferation to terminal differentiation of specific cell types. Since neogenin is expressed on growing neurites and downregulated at termination of neurite growth, it may also play an important role in many of the complex functional aspects of neurite extension and intercellular signaling.
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PMID:Neogenin, an avian cell surface protein expressed during terminal neuronal differentiation, is closely related to the human tumor suppressor molecule deleted in colorectal cancer. 780 78

We describe a patient with adenosquamous carcinoma of the prostate. His history suggests a common histogenesis of the glandular and squamous elements of the tumor. A 60-year-old white man had adenocarcinoma of the prostate diagnosed by biopsy and then underwent radical prostatectomy, which showed adenosquamous carcinoma. Immunoperoxidase in the glandular component was positive for prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), and low molecular weight keratin CAM 5.2 but was negative for high molecular weight keratin AE-3. The squamous component was negative for PSA, PAP, and CAM 5.2 but positive for AE-3. Previously reported patients with adenosquamous carcinoma of the prostate share a history of radiation or hormonal therapy followed much later by prostatectomy, suggesting that adenosquamous carcinoma consists of residual primary adenocarcinoma and metaplastic squamous epithelium caused by radiation or hormonal treatment. However, the present case lacks this history, suggesting that the two types of epithelia may have developed concurrently.
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PMID:Adenosquamous carcinoma of the prostate. 782 10

The analysis of human colorectal tumors has revealed frequent loss of heterozygosity (LOH) of the long arm of chromosome 18. A novel gene, DCC (deleted in colorectal cancer), located within the region of LOH on chromosome 18q was identified and has been implicated as a tumor suppressor gene. We have now shown that DCC encodes a membrane-bound protein of the immunoglobulin-CAM family, as demonstrated by cell-surface labeling, immunohistochemical analysis, and sequencing of cDNA clones. The DCC protein was found in axons of the central and peripheral nervous system and in differentiated cell types of the intestine. Colorectal tumors that lost their capacity to differentiate into mucus producing cells uniformly lacked DCC expression and loss of a chromosome 18q allele was often accompanied by loss of DCC expression in colon tumors. These results provide evidence that DCC encodes a cell surface-localized protein and emphasize the inverse relationship between differentiation and tumorigenesis.
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PMID:The DCC gene product in cellular differentiation and colorectal tumorigenesis. 792 22

The cell-cell adhesion receptor, Mel-CAM/MUC18, is highly expressed on metastatic melanoma cells and is also detectable on primary melanomas but not on normal melanocytes. Previous studies have shown that increased Mel-CAM/MUC18 expression correlates with tumor thickness and metastatic potential. We show here that normal melanocytes and nevus cells in culture express Mel-CAM/MUC18, but expression is down-regulated when cells are co-cultured with keratinocytes. Such keratinocyte-mediated regulation of Mel-CAM/MUC18 expression on melanocytes, nevus cells, and early melanomas can also be demonstrated in situ in patients' specimens. On the other hand, melanoma cells from primary and metastatic lesions constitutively express Mel-CAM/MUC18, and keratinocytes have no modulatory effect. These results suggest that contact between keratinocytes and human melanocytic cells modulates Mel-CAM/MUC18 expression, raising the possibility that escape from keratinocyte control during melanoma development leads to expression of antigens that contribute to the malignant phenotype.
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PMID:Regulation of Mel-CAM/MUC18 expression on melanocytes of different stages of tumor progression by normal keratinocytes. 794 74

We report a case of a medullary carcinoma of the left lobe of the thyroid gland that occurred in a 57-year-old woman. The patient had undergone surgery for treatment of a bilateral-functioning pheochromocytoma when she was 39 years old. A medullary carcinoma of the thyroid gland and/or a pheochromocytoma had also been diagnosed in other family members. The tumor was composed of cells arranged in nests and large sheets separated by fibrous stroma that contained amyloid deposits. Elongated cells with thin, branched cytoplasmic projections that were strongly reminiscent of sustentacular cells usually found in paragangliomas were seen among the neoplastic cells. Immunohistochemical study showed a diffuse positive reaction for calcitonin and low-weight keratins (CAM 5.2) in neoplastic cells, whereas the sustentacular cell-like cells were positive for S100 protein. The reaction for thyroglobulin was negative. Electron microscopy disclosed large numbers of typical neurosecretory granules in the cytoplasm of tumor cells. The sustentacular cell-like cells showed elongated cytoplasmic processes and lacked neurosecretory granules. We concluded that the finding of sustentacular cell-like cells in a medullary carcinoma of the thyroid gland made its differential diagnosis from paraganglioma more problematic.
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PMID:Medullary carcinoma of the thyroid gland with sustentacular cell-like cells in a patient with multiple endocrine neoplasia, type IIA. Report of a case with ultrastructural and immunohistochemical studies. 794 93

Immunohistochemical staining was performed on 145 biopsies with a diagnosis of undifferentiated or poorly differentiated tumor in order to classify them into lymphoid, epithelial, or mesenchymal in origin. It was possible to arrive at a histogenetic diagnosis on immunostaining in 85.5% of cases. Immunostaining confirmed the diagnosis in 32.4% and contributed to diagnosis in 53.1%. Malignant lymphoma was the most common diagnosis (35.9%), followed by carcinoma (23.4%). A panel of antibodies consisting of anti-common leucocyte antigen (LCA), anti-epithelial membrane antigen (EMA), anti-cytokeratin (CK), anti-low to intermediate molecular weight cytokeratin (CAM 5.2), anti-S-100 protein (S-100), and anti-vimentin (VM) may resolve, to a large extent, some of the common diagnostic problems.
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PMID:Undifferentiated tumors: an immunohistochemical analysis on biopsies. 799 Apr 86

Atypical carcinoids of the thymus are rare neoplasms of uncertain prognosis. We have studied eight cases (six male, two female; age range 48-60 years, mean 55 years), none with evidence of a paraneoplastic neuroendocrine syndrome. Tumour size was large and ranged from 7.5 to 10 cm. Microscopically, all had a nesting/insular or trabecular pattern, eosinophilic cytoplasm, round nuclei with fine chromatin and small nucleoli. No small cell features were evident. Mitotic activity ranged from 2 to 21 per 1.52 mm2. Focal necrosis was seen in all cases. All were positive for cytokeratin (AE1/AE3, CAM 5.2) and the neuroendocrine markers NSE, synaptophysin and chromogranin; five cases were positive for calcitonin. On electronmicroscopy all contained dense core granules, often numerous. Three cases were stage I and five stage III (infiltrating lung or chest wall). Follow-up information was available in four cases (one stage I and three stage III): the stage I tumour had local recurrence and metastasis to the lung within a year whilst the three patients with stage III tumours died of liver, bone and brain metastases within 3 years.
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PMID:Atypical carcinoid tumour of the thymus: a study of eight cases. 804 26

The clinical and pathological features of 77 cases of intraductal (intracystic) papillary carcinoma (IPC) of the breast are reported. It should be recognized as an intraductal carcinoma variant and distinguished from invasive papillary carcinoma. Intraductal papillary carcinoma remains a difficult diagnosis as there are four different epithelial growth patterns any of which may predominate. Low grade nuclear features occur in one third of cases, a so-called "stratified spindled cell" epithelial proliferation with bland morphology occurs in one quarter of cases, and a dimorphic population of malignant cells, which may in part be confused with myoepithelial cells, occurs in one quarter of cases. The 77 cases studied were from the 10-year interval 1970 to 1979. The effect on prognosis of cytoarchitectural features, duct wall and stromal invasion, and associated intraductal carcinoma were evaluated. The contribution of immunohistochemistry to the diagnosis using antibodies to smooth muscle actin, S-100 protein, and CAM 5.2 was examined. The 10-year survival rate was 100%, and the 10-year disease-free survival rate was 91%. Mastectomy had been performed in 72% of patients. Three of the patients developed metastases; two were alive with tumor and one died of other causes. Six patients had local recurrence in the chest wall; one was alive without disease, two were alive with tumor, and three died of other causes. An associated intraductal carcinoma of usual nonnecrotic or comedo type was present in 40% of all cases. When IPC recurred or metastasized, it did so as invasive papillary carcinoma in six of seven cases. Stromal invasion was found in 13 patients. Local recurrence developed in two of these. Invasion was not seen in any of the three patients who developed metastases. However, this may be a function of sampling as there was an average of 5.2 tumor sections per case. Patients with low grade tumors had no recurrence or metastasis, and in the absence of invasion may be treated by local excision. Patients with higher grade tumors have an increased risk of recurrence and metastasis.
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PMID:Intraductal (intracystic) papillary carcinoma of the breast and its variants: a clinicopathological study of 77 cases. 805 21


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