Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0009402 (colorectal cancer)
 53,228 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The polymorphism at codon 201 of the "deleted in colorectal carcinoma" (DCC) gene has been liked to susceptibility to colorectal cancer. However, its clinicopathological significance has not been reported. We examined the codon 201 polymorphism and loss of heterozygosity (LOH) by PCR-restriction fragment length polymorphism (PCR-RFLP) in 59 colorectal cancers, 48 samples from transitional mucosa and 67 samples from normal mucosa. The frequencies of the polymorphism did not significantly differ from normal to transitional mucosa and to tumor, but LOH was increased from transitional mucosa to tumor. Almost all of the LOH cases showed the polymorphism. The polymorphism was increased from well/moderately to poorly differentiated and to mucinous carcinoma (P=0.03). The polymorphism was more frequently seen in advanced stages than in earlier stages (P=0.02), and further predicted worse survival (P=0.04). The data suggest that the codon 201 polymorphism of the DCC gene was a target of LOH, and predicted prognosis in colorectal cancer patients.
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PMID:Codon 201 polymorphism of DCC gene is a prognostic factor in patients with colorectal cancer. 1278 29

Colorectal carcinoma with microsatellite instability (MSI-H) has a characteristic clinicopathologic profile, typically forming right-sided, lymphocyte-rich tumors that are often mucinous. Mucinous histology in general has been linked to adverse prognosis in some studies, but not in others. MSI-H carcinoma, in contrast, has a better prognosis than microsatellite stable carcinoma in most studies. We assessed the relationship between MSI status, clinicopathologic features and outcome for 248 consecutive patients with resected mucinous carcinoma. All cases were reviewed to confirm mucinous histology. Immunohistochemical stains for DNA mismatch repair enzymes hMLH1, hMSH2 and hMSH6 were performed on a representative block from each case. Tumors lacking expression of a mismatch repair enzyme were designated MSI-H; all others were classified as microsatellite stable. Age, sex, tumor size, site, grade, stage, growth pattern, Crohn's-like reaction, vascular invasion and number of tumor-infiltrating lymphocytes were evaluated without knowledge of MSI status or patient outcome. 72 (29.3%) mucinous carcinomas were MSI-H. Compared to microsatellite stable mucinous cancers, they were more likely to be right-sided (83.3 vs 48.6%, P<0.001), have a Crohn's -like reaction (65.7 vs 29.8%, P<0.001) and have many tumor infiltrating lymphocytes (72.2 vs 20.8%, P<0.001). MSI-H mucinous cancers presented more often as localized disease (66.7 vs 38.1%, P<0.001) and less often with lymph node (26.4 vs 44.9%) or distant (4.2 vs 16.5%) metastases. In univariate analysis, MSI had a favorable effect on age-adjusted survival (hazard ratio 0.597, P=0.02). In multivariate analysis, age, grade, Crohn's-like reaction and stage were independent predictors of survival, but MSI status was not. In conclusion, MSI-H mucinous carcinomas are right-sided, low-stage tumors with Crohn's-like reaction and tumor-infiltrating lymphocytes. The outcome for MSI-H mucinous carcinoma is better than that of microsatellite-stable mucinous carcinoma, but MSI status is not an independent predictor of survival.
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PMID:Mucinous carcinoma of the colon: correlation of loss of mismatch repair enzymes with clinicopathologic features and survival. 1501 35

Hereditary non-polyposis colorectal cancer (HNPCC) accounts for approximately 2 to 4% of the total colorectal cancer burden. For economic reasons a diagnostic "stepladder" is recommended. After evaluation of the family history, diagnostic microsatellite instability (MSI) analysis has found its place as a valuable screening tool for HNPCC. Immunohistochemical analysis can help to pinpoint the affected gene. The detection of a mutation in one of the responsible mismatch repair gene confirmed the diagnosis HNPCC. Here we demonstrate our experience of some important pitfalls that will be discussed in this study. In MSI testing, one potential source for false-negative results is intralesional heterogeneity. We demonstrate examples of a flat adenoma and a carcinoma, which required laser microdissection to correctly determine the microsatellite status. In these lesions manual microdissection, the most frequently applied method, was not sufficient. However, the number of cells obtained by using laser microdisssection can fall below a necessary minimum, which can also cause false-negative results of MSI analysis, as shown here in a mucinous carcinoma. In addition, evaluation of immunohistochemically stained tissue slides requires experience to avoid false-positive or false-negative interpretation. A case with two synchronous colorectal cancers revealed loss of MSH2 expression in one carcinoma, whereas the second carcinoma stained positively leading to a false-negative interpretation. In some cases, false-positive results can be obtained, if a perinuclear-staining pattern is interpreted as positive. In summary, there are several potential pitfalls in the molecular screening for HNPCC. Therefore the importance of correct interpretation of clinical data, immunohistochemistry, and microsatellite analysis in combination, performed by a pathologist with experience in molecular genetics is essential. In addition, laser microdissection of tumor areas that have been chosen by a pathologist is highly recommended in cases that cannot be resolved with manual microdissection.
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PMID:Challenges and pitfalls in HNPCC screening by microsatellite analysis and immunohistochemistry. 1550 69

Loss of imprinting (LOI), the biallelic expression of an imprinting gene, of insulin-like growth factor 2 (IGF2) has been reported to be associated with colorectal carcinogenesis because of its high prevalence in normal colorectal mucosa as well as cancerous tissue in patients with colorectal cancer. However, the characteristics of colorectal cancer associated with IGF2 LOI have not been clearly demonstrated. In this study, we investigated the IGF2 LOI status of tumor and normal mucosa in 255 consecutive patients with colorectal cancer. Of these, 95 were informative for IGF2 LOI, by direct sequencing of mRNA of IGF2. Regarding the LOI status in each patient, the prevalence of LOI in nontumorus normal mucosa was significantly higher in cases with LOI-positive cancer than in those with LOI-negative cancer (p < 0.001). Concerning the clinicopathological characteristics of LOI-positive cancer, the prevalence of poorly differentiated or mucinous carcinoma (p = 0.016) and of right-sided locations (p = 0.009) were significantly higher than those of LOI-negative cancer. Contrary to past reports that revealed a significant correlation between microsatellite instability (MSI) and IGF2 LOI in a relatively small series of noncohort patients, our study did not find a statistically significant difference in LOI-positive rate between MSI-positive and -negative cases. Our results suggested the presence of a particular type of colorectal cancer associated with the proximal colon and poor differentiation, but independent of MSI. These results may contribute to clarification of the mechanism of colorectal tumorigenesis and to determining an appropriate screening strategy for colorectal carcinoma.
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PMID:Clinicopathological characteristics of colorectal cancers with loss of imprinting of insulin-like growth factor 2. 1643 31

Microsatellite instability (MSI) is present in approximately 15-20% of sporadic colorectal cancers. However, despite the increased prevalence of absent hMLH1 expression and MSI in colorectal cancer in the elderly, few attempts have been made to define it in detail. The aim of the present paper was to correlate age-related alterations in absent hMLH1 expression and MSI with various histological types of colorectal carcinoma. hMLH1 expression and microsatellite status were studied in 184 colorectal carcinomas (49 well-differentiated, 49 moderately differentiated, 49 poorly differentiated adenocarcinomas, and 37 mucinous carcinomas). The prevalence of absent hMLH1 expression was higher in poorly differentiated adenocarcinoma (63%) and mucinous carcinoma (43%) than in well- (8%) and moderately (12%) differentiated adenocarcinomas. MSI was found more frequently in poorly differentiated adenocarcinoma (69%) and mucinous carcinoma (41%) than in well- and moderately differentiated adenocarcinomas (8% and 6%, respectively). Age-related differences in absent hMLH1 expression and MSI were found only in poorly differentiated adenocarcinoma, in which the prevalence of medullary-type carcinoma increased with advancing age. These results indicate that an age-related increase of medullary-type tumors in poorly differentiated adenocarcinoma may play an important role in the increase of absent hMLH1 expression and MSI in colorectal carcinoma.
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PMID:Age-related alteration in the association of microsatellite instability with absent hMLH1 expression and histological types of colorectal carcinoma. 1698 16

We herein report a rare case of primary mucinous carcinoma of the duodenum associated with hereditary nonpolyposis colorectal cancer (HNPCC). A 50-year-old man known to have HNPCC based on the Amsterdam criteria I was admitted because of the presence of a duodenal tumor. Duodenoscopy revealed an ulcerated tumor in the posterior wall of the second portion of the duodenum and the malignancy was confirmed by a biopsy. He underwent a pylorus-preserving pancreaticoduodenectomy with a regional lymph node dissection. The histological diagnosis was mucinous carcinoma of the duodenum with lymph node metastasis. High-frequency microsatellite instability (MSI-H) was identified in both the colon and a duodenal specimen based on a microsatellite assay. A germline mutation in the hMSH2 gene was also identified. Even though extracolonic malignancies are associated with HNPCC, duodenal cancer is nevertheless very rare, and only two cases have been reported over the past 20 years. The present case is therefore only the third such case and the patient is herein described with a brief review of the literature.
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PMID:Mucinous carcinoma of the duodenum associated with hereditary nonpolyposis colorectal cancer: report of a case. 1712 47

Histopathologically, the incidence of mucinous carcinomas in Europe and the United States is approximately 10% and that in Japan is low, at 2.9% to 7.4%. The prognosis of mucinous carcinomas is generally thought to be poor, but their clinical and histological features are not well known. In this study, we attempted to clinicopathologically characterize colorectal mucinous carcinomas. Of the 607 colorectal cancer patients, a group of 20 mucinous carcinoma patients (3.3%) and a group of 553 control patients were included in this study. The mucinous carcinomas were subclassified into the following two types to analyze clinicopathological parameters and outcomes: the papillotubular (PT) type and the mucocellular (MC) type. Clinicopathologically, the MC type showed higher rates of venous invasion, lymph node metastasis, liver metastasis, and peritoneal dissemination and higher frequencies of TNM stage III and IV cancers than the PT type. The MC type had a significantly poorer 3-year survival rate of 27% compared with 60% for the PT type. The MC-type mucinous carcinomas showed a significantly higher expression rate (37.5%) of MMP-9 than that (16.6%) in the PT-type mucinous carcinomas. Overall, the colorectal mucinous carcinomas progressed more rapidly and had a poorer prognosis than the control (nonmucinous) cancers. The histological subclassifications MC and PT tended to be molecular-biologically different, and the MC type was poorer in terms of clinicopathological parameters and outcomes.
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PMID:Clinicopathological study of the colorectal mucinous carcinomas. 1725 36

Insulin-like growth factor (IGF) and its receptor (IGF-IR) play an important role in mitogenesis, apoptosis, growth, and proliferation of several types of cancers. Overexpression of IGF-IR in colorectal cancer is associated with increase of cancer cell proliferation and migration as well as inhibition of apoptosis. In our previous reports we demonstrated correlations between IGF-IR and apoptosis. Moreover, we observed relationships between connexin26 (Cx26) expression and apoptotic markers in human colorectal cancer. Recently, it has been shown that expression of connexins and gap junction (GJ) functions are also regulated by growth factors, including IGF-I. Therefore, in this study we have focused on the relationships between IGF-IR and Cx26 as well as Bcl-xL expression. A total number of 115 cases of colorectal cancer were examined by immunohistochemistry, using the avidin-biotin-peroxidase method. Associations among the above proteins were assessed in the entire group of colorectal cancer patients and its subgroups, depending on lymph node involvement (N0 and N1), histological grade (G2 and G3), extent of tumor growth (pT1+pT2 and pT3+pT4), histopathologic type (adenocarcinoma and mucinous carcinoma), sex, age (<or=60 and>60), and tumor site (colon and rectum). The expression of IGF-IR, Cx26, and Bcl-xL was noted in 47%, 56.5%, and 75.6% of the tumors, respectively. In the entire group of patients we found a positive correlation between IGF-IR and Cx26 (P<0.0001, r=0.374) as well as between IGF-IR and Bcl-xL (P<0.0001, r=0.344). Our results may suggest that the insulin-like growth system is involved in regulation of apoptosis and probably connexin expression in colorectal cancer cells.
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PMID:Insulin-like growth factor-I receptor correlates with connexin 26 and Bcl-xL expression in human colorectal cancer. 1738 70

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder characterized by exacerbations and remissions. The degree of inflammation as assessed by conventional colonoscopy is a reliable parameter of disease activity. However, even when conventional colonoscopy suggests remission and normal mucosal findings, microscopic abnormalities may persist, and relapse may occur later. Patients with long-standing, extensive ulcerative colitis have an increased risk of developing colorectal cancer. Ulcerative colitis-associated colorectal cancer is characterized by an early age at onset, poorly differentiated tumor cells, mucinous carcinoma, and multiple lesions. Early detection of dysplasia and colitic cancer is thus a prerequisite for survival. A relatively new method, magnifying chromoscopy, is thought to be useful for the early detection and diagnosis of dysplasia and colitic cancer, as well as the prediction of relapse.
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PMID:Magnifying chromoscopy, a novel and useful technique for colonoscopy in ulcerative colitis. 1755 98

Chronic inflammation of mucosal surfaces renders them increasingly susceptible to epithelial cancers both in humans and mice. We have previously shown that anti-inflammatory CD4(+)CD45RB(lo)CD25(+) regulatory (Treg or T(R)) lymphocytes down-regulate inflammation and block development of bacteria-triggered colitis and colorectal cancer (CRC) in 129/SvEv Rag2-/- mice. Interestingly, T(R) cells collected from Interleukin (IL)-10-deficient cell donors not only failed to suppress carcinogenesis but instead promoted invasive mucinous colonic carcinoma with a strong gender bias expressing in male mice. We found we show that peritoneal invasion in this model is dependent on pleiotropic cytokine IL-6. Mucinous carcinoma arose rapidly and consistently after treatment with IL10-/- T(R) cells, which were found to express Foxp3+ and localize throughout tumor tissue. Carcinogenesis was rapidly reversible with transfer of wild type IL10-competent T(R) cells. Likewise, treatment with IL10-Ig fusion protein was sufficient to revert the lesions histologically, and restore inflammatory cytokine and oncogene expression to base line levels. These studies indicate an essential role for IL 6 in this CRC phenotype. Furthermore, immune-competent T(R) cells were important not only for preventing pathology but also for constructive remodeling of bowel following tumorigenic microbial insults. These data provide insights into etiopathogenesis of inflammation-associated epithelial invasion and maintenance of epithelial homeostasis.
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PMID:Rapid reversal of interleukin-6-dependent epithelial invasion in a mouse model of microbially induced colon carcinoma. 1772 75


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