Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum selenium concentration (scSe) (microgram/l) was comparatively measured in healthy persons (n = 202), patients with colorectal adenoma(s) (n = 44) and colorectal carcinoma (n = 48). In patients with adenoma(s) scSe (59.05 +/- 15) was significantly lower (p < 0.001) compared with scSe in the control group (66.8 +/- 14.43). Hyposelenemia was more pronounced in patients with multiple polyps (n = 11) than in patients with single adenoma (n = 33) (p < 0.05). Patients with colorectal carcinoma had also significant decrease in scSe (50.93 +/- 13.81) compared with the control group (p < 0.001 and with the adenoma patients (p < 0.001). According to the analysis of variance, highly significant differences were found among the cancer patients stratified in Dukes' stages A to D (p < 0.001), indicating a strong negative correlation between extension of cancer and hyposelenemia. Furthermore, hyposelenemia seemed to be more pronounced in the mucinous type of carcinoma than in adenocarcinoma (p = 0.056). This results indicate that hyposelenemia is strongly associated with colorectal neoplasia (including extension and severity of the disease) and that it may not only be a result but also one of tumorogenic factors. That means that selenium supplementation could be important in prevention or even adjuvant therapy of colorectal cancer.
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PMID:[Differences in serum selenium concentration in probands and patients with colorectal neoplasms in Zagreb, Croatia]. 801 64

The measurement of both immune complex-bound and free unbound tumor-associated antigen was evaluated independently on a panel of sera from colon cancer patients by radioimmunoassay (RIA). A monoclonal antibody (mAb 46.3) raised against secreted antigens from human colon cancer cells in vitro was utilized in the RIA. When circulating immune complexes alone were analyzed, the data demonstrated that 5 of 5 (100%) Dukes' A patients and 11 of 16 (69%) Dukes' B patients had elevated levels of immune complexes reactive with mAb 46.3. Analysis of free circulating antigens demonstrated elevated levels of mAb 46.3-reactive antigen present in 5 of 5 (100%) Dukes' A patients and 15 of 16 (95%) Dukes' B patients. However, by analyzing total reactivity, defined by combining results from RIA with free and immune complex-bound antigen, the sensitivity of detection for Dukes' B increased to 16 of 16 (100%). Total antigen levels in sera from patients with benign diseases (ulcerative colitis, Crohn's disease, adenoma) were not significantly different from normal controls. Analysis of both free and bound antigen in RIA is, therefore, a more sensitive indicator than RIA with immune complex alone. For the advanced stages of disease, only 1 of 5 (20%) Dukes' C and 0 of 5 (0%) Dukes' D sera were positive for reactive immune complexes. When the combined RIA was evaluated, 3 of 5 (60%) and 1 of 5 (20%) Dukes' C and D sera, respectively, were positive with mAb 46.3. Taken together, these results show that RIA with mAb 46.3 is a sensitive indicator for the early stages of colon cancer.
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PMID:Improved detection of the early stages of colon cancer by determining both free circulating and immune complex-bound antigens reactive with monoclonal antibody. 803 25

From October 1987 to March 1991, 21 (8%) superficial early cancers were found among 256 early colorectal cancers (Dukes A and B1). Superficial early cancers were defined as early cancers less than 3 mm in height. These tumors were found scattered throughout the large intestine and were often observed as reddish spots, which were easily overlooked without careful observation. Histologically, 19 (90%) of them were well-differentiated adenocarcinomas, and five (24%) of them reached the submucosal layer. Eighteen (86%) of them were not associated with adenoma.
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PMID:Clinicopathological features and endoscopic diagnosis of superficial early adenocarcinomas of the large intestine. 832 93

Six hundred twenty-one asymptomatic persons with negative fecal occult blood tests (ages 50-75 yr), including 496 with no known risk factors for colorectal cancer and 125 with a single first-degree relative with a history of colonic neoplasia developed after age 40, underwent screening colonoscopy. Three Dukes A cancers were detected in average-risk persons. The overall prevalence of adenomatous polyps was 27%. Multiple logistic regression analysis revealed that increasing age and male gender were both strong predictors of colonic neoplasia (p < 0.001). A positive family history of a single first-degree relative with colorectal cancer was not associated with an increased prevalence of colonic neoplasia (p = 0.29), although an effect may be present if the relative was < 60 yr at diagnosis. Overall 16% of males and 7% of women > or = 60 yr had at least one adenoma that was large (> or = 1 cm in size), villous or tubulovillous, or had grade 3 dysplasia. We conclude that the prevalence of colonic neoplasia in asymptomatic persons with negative fecal occult blood tests is substantial, particularly in elderly males. A family history of a single first-degree relative diagnosed at age > or = 60 yr with colorectal cancer is not associated with an increased prevalence of colonic adenomas.
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PMID:Colonic neoplasia in asymptomatic persons with negative fecal occult blood tests: influence of age, gender, and family history. 850 71

The assessment of cell proliferation in colorectal tissue may provide information with both prognostic and therapeutic implications. A variety of methods are available, including flow cytometric estimations of S phase fraction, immunohistochemical and autoradiographic visualization of exogenous and endogenous proliferation proteins, and morphological and stathmokinetic techniques. There is some correlation between Dukes stage and proliferation state features, and there is increased proliferative activity throughout the adenoma-carcinoma sequence. Data on cell proliferation rates are difficult to obtain. When correctly applied, the metaphase arrest technique remains the 'gold standard' of measuring proliferation, but its usefulness in clinical practice is limited. Recent studies have employed dual measurement flow cytometry and double labelling techniques to produce rate data.
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PMID:Colorectal cell kinetics. 869 29

A series of 44 sporadic mucinous colorectal carcinomas was analysed for microsatellite instability; 30 consecutive sporadic non-mucinous colorectal cancers served as controls. Mucinous carcinomas showed microsatellite instability more frequently than non-mucinous cancers: 26/44 and 8/30, respectively (P = 0.005); the difference was higher for cancers with two or more microsatellite alterations: 12 of the 44 mucinous carcinomas versus one of the 30 non-mucinous carcinomas (P = 0.007). On comparing the clinico-pathological features of mucinous carcinomas with and without microsatellite instabilities, no differences were found with respect to the following variables; sex ratio, tumour localization, tumour size, peritumoural lymphocytic infiltration, Crohn's-like lymphoid reaction, peritumoural fibrosis, Dukes' stage, and relationship with adenoma. Mucinous cancers with DNA replication errors were characterized by three features: onset in younger patients (P < 0.05); exophytic gross shape (P = 0.03); and an expanding pattern of growth (P = 0.003). Of the 12 mucinous carcinomas with instability in two or more microsatellites, ten (83.3 per cent) exhibited an expanding pattern of growth, while mucinous cancers with instability in one microsatellite or without genomic instability showed no distinctive growth pattern. This study confirms the relationship between microsatellite instabilities and mucin production in colorectal carcinomas, but shows that replication error RER-positive and RER-negative mucinous cancers differ in few clinico-pathological features. These differences are only in part similar to those previously reported in RER-positive colorectal carcinomas. These data indicate that mucinous carcinoma of the large bowel could represent a histological subset separate from other histotypes.
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PMID:Microsatellite instability in sporadic mucinous colorectal carcinomas: relationship to clinico-pathological variables. 930 57

A retrospective analysis of polypoid lesions of the colon larger than 1 cm was performed with the aim to study their characteristics and a proper surveillance schedule. We reviewed all colon polypoid lesions larger than 1 cm found and treated during the period January 1984- December 1993 that were not considered cancer macroscopically. The records of 361 patients with 391 polyps are the object of this report. The polyps were divided into subgroups according to size: A) less than 20 mm, B) between 21 and 30 mm, and C) larger than 30 mm. Out of 391 polypoid lesions 373 were adenomas: 60% were found in males. The age group distribution showed no differences among the subgroups. The pedunculated type showed a decrease from 69.1% to 43.3% with the increasing of size: inverse figures were observed for sessile polyps. The lesions were mainly located in left colon. Synchronous adenomas were found in 25.4% patients, and metachronous and previous adenomas respectively in 24.8% and 5.2%: no significant difference was present in the subgroups. Synchronous malignancy in the colon was found in 2% of the patients. Histological characteristics demonstrated a decrease of tubular adenoma from 46.5% to 22.6% from subgroup A to C, while villous adenomas increased inversely from 6.6% to 15.1%. The presence of severe dysplasia ranged from 20.9% to 56.1% in subgroups A and C, respectively, and adenomas with invasive cancer showed a significant increase from the subgroup A to C, respectively from 4.3% to 10.5%. During an average 36-month follow-up we observed 2 metachronous colon cancers, surgically treated in Dukes stage B, 84 metachronous adenomas, all less than 10 mm and without malignant alterations. Our data confirm other literature reports regarding the profile of colon adenomas with an increasing risk of malignancy with the increase of size and the presence of villous structure. In our opinion the assessment of a "clean colon" status is important when an adenoma is found in the colon. The proper follow-up for adenomas must be tailored for any individual patient when risk factors such as size, villous structure, personal and family history of neoplastic lesions of the colon are present. The follow-up schedule, presently recommended for colon adenomas, must be flexible according to these parameters.
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PMID:Medium-large polyps of the colon: a contribution for their clinical profile and a proper surveillance. 938 7

An increased expression of nitric oxide synthase (NOS) has been observed in human colon carcinoma cell lines as well as in human gynecological, breast, and central nervous system tumors. This observation suggests a pathobiological role of tumor-associated NO production. Hence, we investigated NOS expression in human colon cancer in respect to tumor staging, NOS-expressing cell type(s), nitrotyrosine formation, inflammation, and vascular endothelial growth factor expression. Ca2+-dependent NOS activity was found in normal colon and in tumors but was significantly decreased in adenomas (P < 0.001) and carcinomas (Dukes' stages A-D: P < 0.002). Ca2+-independent NOS activity, indicating inducible NOS (NOS2), is markedly expressed in approximately 60% of human colon adenomas (P < 0.001 versus normal tissues) and in 20-25% of colon carcinomas (P < 0.01 versus normal tissues). Only low levels were found in the surrounding normal tissue. NOS2 activity decreased with increasing tumor stage (Dukes' A-D) and was lowest in colon metastases to liver and lung. NOS2 was detected in tissue mononuclear cells (TMCs), endothelium, and tumor epithelium. There was a statistically significant correlation between NOS2 enzymatic activity and the level of NOS2 protein detected by immunohistochemistry (P < 0.01). Western blot analysis of tumor extracts with Ca2+-independent NOS activity showed up to three distinct NOS2 protein bands at Mr 125,000-Mr 138,000. The same protein bands were heavily tyrosine-phosphorylated in some tumor tissues. TMCs, but not the tumor epithelium, were immunopositive using a polyclonal anti-nitrotyrosine antibody. However, only a subset of the NOS2-expressing TMCs stained positively for 3-nitrotyrosine, which is a marker for peroxynitrite formation. Furthermore, vascular endothelial growth factor expression was detected in adenomas expressing NOS2. These data are consistent with the hypothesis that excessive NO production by NOS2 may contribute to the pathogenesis of colon cancer progression at the transition of colon adenoma to carcinoma in situ.
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PMID:Frequent nitric oxide synthase-2 expression in human colon adenomas: implication for tumor angiogenesis and colon cancer progression. 944 14

A three-colour FISH approach using centromere-specific DNA probes was used to analyse the number of chromosomes 7, 17 and 18 found within individual tumour cells and the results were correlated with total DNA ploidy determined by image analysis. FISH analysis showed a high level of heterogeneity in the majority of tumour samples with only 7 out of 44 samples having a single chromosome profile occurring in greater than 40% of the cells. Analysis of the modal chromosome number showed that a diploid 2/2/2 profile for chromosome 7, 17 and 18 respectively occurred most commonly. The DNA ploidy index for biopsies with a 2/2/2 profile varied between 0.93-2.06. No gain of chromosome was observed in the adenoma samples or Dukes A tumours but a loss of chromosome 18 was seen in 50% of these early carcinomas. A modal chromosome profile of 4/2/2 was commonly found in Dukes B and C tumours suggesting that endoreduplication with the relative loss of chromosome 17 and 18 is common in advanced cancers. The DNA ploidy index for the more advanced tumours was also variable but significantly higher than that found in the early tumours and non-tumour controls. In conclusion, this work shows that tumours are highly heterogeneous and that the majority of tumours consist of a large number of cell sub-populations with respect to the expression of chromosomes 7, 17 and 18.
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PMID:Multiple cell populations in colorectal carcinomas: analysis by 3-colour fluorescence in situ hybridization. 945 89

Both deleted in colorectal carcinoma (DCC) and mutated in colorectal carcinomas (MCC) genes are newly found tumour suppresser genes in colorectal carcinomas. In this study mutations of DCC gene and loss of heterozygosity (LOH) of MCC gene were detected with Southern blot and PCR methods respectively. The study consisted of 30 cases of colorectal adenoma (10 with mild, 10 with moderate and 10 with severe dysplasia) and 33 cases of colorectal carcinomas (13 highly, 10 moderately and 10 poorly differentiated, meanwhile 9 in Dukes A, 10 in B and 14 in C stage). Their paired normal colorectal mucosa served as control. The results were as follows: mutation of DCC was not found in any specimen with normal mucosa or with adenoma of mild and moderate dysplaaia, while it was found in one if those with severe dysplasia. Mutation of DCC was, however, found in 7 of the 33 specimens with carcinoma and there was a correlation between the positive rate and the differentiation or staging of the carcinoma. LOH of MCC was not found in normal mucosa, but it was found in 2/10, 3/10 and 4/10 of the adenoma specimens with mild, moderate and severe dysplasia respectively. 18/33 of the carcinoma specimens was found to have LOH of MCC and there was also a correlation between the positive rate and the differentiation or staging of the carcinoma. These results suggest that the frequency of multiple gene changes increase with poor differentiation and increased staging of colorectal carcinoma.
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PMID:[A study on the changes of DCC and MCC genes in colorectal carcinoma and adenoma]. 959 13


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