Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adenocarcinoma of the colon is one of the most prevalent and lethal of all human malignancies. The early diagnosis and management of this disease could be improved if biological markers, whose expression was restricted to malignant colon cells, were identified. Sucrase-isomaltase is a glycoprotein hydrolase expressed throughout the small intestine and fetal colon but not in the normal adult colon. This study shows that the expression of enzymatically active sucrase-isomaltase is a ubiquitous property of primary and metastatic colon adenocarcinoma. Significant sucrase enzyme activity (i.e., greater than 5 mU/mg protein) was observed in 16 colon carcinomas but not in adjacent normal colon mucosa. Sucrase-isomaltase messenger RNA was identified in all tumors using reverse transcriptase polymerase chain reaction. Using a quantitative polymerase chain reaction analysis, this study shows that the amount of sucrase-isomaltase messenger RNA in tumors examined (3.4 x 10(-8) to 3.19 x 10(-7) micrograms/micrograms total RNA) was greater than in adjacent mucosa (0 to 3.4 x 10(-8) micrograms/micrograms total RNA). This induction of sucrase-isomaltase messenger RNA and enzyme activity was corroborated by immunostaining. Of 30 colon adenocarcinomas examined, 80% were positive for sucrase-isomaltase. In addition, all colon carcinoma metastases examined were positive for sucrase-isomaltase. The staining pattern was distinct and demarcated tumor cells from the surrounding histologically normal tissue. No sucrase-isomaltase staining was seen in normal mucosa from the same patients. With the exception of lung, no sucrase-isomaltase immunostaining was observed in a variety of examined noncolonic adenocarcinomas. Thus, the specificity and ubiquity of sucrase-isomaltase expression in adenocarcinomas of the colon can be exploited to improve the clinical management of this disease. In addition, studies on the structure of the sucrase-isomaltase gene and its regulatory elements should contribute toward understanding the alteration of gene expression by oncogenic transformation of the colonic mucosa.
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PMID:Expression of enzymatically active sucrase-isomaltase is a ubiquitous property of colon adenocarcinomas. 170 85

Adenocarcinoma of the pancreas is associated with the worst survival of any form of gastrointestinal malignancy. In spite of the progress in surgical treatment, resulting in increasing resection rates and a decrease in treatment-related morbidity and mortality, the true figures of cure are even today below 3%. The dissemination of pancreatic cancer behind the local tissue compartments restricts the short-term (< 3 years) and long-term outcome for patients who have undergone resection. By histological evaluation, less than 15% of the patients undergoing R(0) resection have a pN(0) status, more than 60% suffer from lymph angiosis carcinomatosa, and more than 50% suffer extrapancreatic nerve plexus infiltration. Hematoxylin and eosin-negative lymph nodes were found to be cancer positive when reverse transcriptase polymerase chain reaction (RT- PCR) or immunostaining was applied to the HE-negative lymph nodes. Cancer of the uncinate process has a very poor prognosis because there are no early symptoms; vessel wall involvement occurs early and frequently; a high association of liver metastasis exists as well. Surgery offers a low success rate, but it provides the only chance of cure. Ductal pancreatic cancer is diagnosed in more than 95% of the cases in an advanced stage; potentially curative resection can be performed only in about 10%-15% of these patients. Major contributions of surgery to improved treatment results are the reduction of surgical morbidity--e.g., early postoperative local and systemic complications--and a decrease of hospital mortality below 3%-5%. In most recently published prospective trials, R(0) resection has been reported to result in an increase in short-term survival beyond that recorded for patients with residual tumor. However, R(0) resection fails to improve long-term survival. In many published R(0) series, standard tissue resection of pancreatic head cancer with the Kausch-Whipple procedure failed to include remote cancer cell-positive tissues in the operative specimen; e.g., N(2)-lymph nodes, nerve plexus, and perivascular extrapancreatic and retropancreatic tissues were not excised. Cancer recurrence after so-called R(0) resection with curative intent is frequently the consequence of cancer left behind. Thus, long-term survival (> 5 years) is observed in a very small group of patients, contradicting the published 5-year actuarial survival rates of 20%-45% for resected patients. The assessment of clinical benefit from surgical or medical cancer treatment should therefore be based on several end points, not only on actuarial survival. Publication of actuarial survival figures must include the number of observed (actual) survivals, the definition of the subset of patients followed after resection, and the total number of patients in the study group; anything less is misleading. In reporting pancreatic cancer treatment trial results after oncological resections, more convincing primary end points to evaluate treatment efficacy are median survival (in months), actual survival at 1-5 years, and progression-free survival (in months). In series with multimodality treatment, clinical benefit response as well as quality of life measurements using the EORTC Quality of Life index C30 (QLQ-C30) are of importance in evaluating survival data. Adjuvant treatment improves survival after oncological resection; however, the short-term and long-term benefit after adjuvant chemotherapy in R(0) as well as in R(1)-(2) resected patients has not yet been underscored by data from controlled clinical trials. The survival benefit (median survival time) of adjuvant chemotherapy or radiochemotherapy has been demonstrated to be 6-10 months. Therefore, after oncological resection of pancreatic cancer each patient should be offered adjuvant treatment. A neoadjuvant treatment protocol for pancreatic cancer, however, has not been established.
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PMID:Treatment of pancreatic cancer: challenge of the facts. 1292 7

Adenocarcinoma of the prostate comprises 95% of all prostate cancer. Commercially available primary cultures of "normal" prostate epithelial cells, PrECs, have been used as a convenient model to investigate neoplastic transformation. Here PrECs were characterized for the expression of lineage- and developmental-specific markers cytokeratin (CK) 8 and 18, p63, chromogranin A, TMEPAI, S100P, NKX 3.1, ANKH, and FN 1 as well as androgen receptor and prostate-specific antigen by Western blot and Northern blot analyses, immunohistochemistry, reverse transcriptase-polymerase chain reaction (RT-PCR), and quantitative real-time PCR. Immunohistochemical staining detected PrECs positive in varying degrees for p63, CK 8, and CK 18, with only the rare cell being positive for chromogranin A. The PrECs also tested positive for p63 protein by Western blot analysis. RT-PCR with PrEC cDNA showed products for FN 1 and S100P but not for ANKH and androgen receptor or prostate-specific antigen. This profile of markers in PrEC cells is consistent with that expected for pubertal prostate epithelial cells.
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PMID:Molecular analysis and characterization of PrEC, commercially available prostate epithelial cells. 1661 9