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Steven Gallinger

Publications and source records attributed to Steven Gallinger.

At least 55 records · Page 3Linked to original sources
PubMed2004

alpha2HS-glycoprotein, an antagonist of transforming growth factor beta in vivo, inhibits intestinal tumor progression.

Transforming growth factor (TGF)-beta1 is associated with tumor progression and resistance to chemotherapy in established cancers, as well as host immune suppression. Here, we show that the serum glycoprotein alpha2-HS-glycoprotein (AHSG) blocks TGF-beta1 binding to cell surface receptors, suppresses TGF-beta signal transduction, and inhibits TGF-beta-induced epithelial-mesenchymal transition, suggesting that AHSG may play a role in tumor progression. In 66 consecutive sporadic human colorectal cancer specimens, we observed a 3-fold depletion of ASHG in tumor compared with normal tissue, whereas levels of other abundant plasma proteins, albumin and transferrin, were equivalent. Using the Multiple intestinal neoplasia/+ (Min/+) mouse model of intestinal tumorigenesis, we found twice as many intestinal polyps overall, twice as many large polyps (>3 mm diameter), and more progression to invasive adenocarcinoma in Min/+ Ahsg-/- mice than in littermates expressing Ahsg. Phosphorylated Smad2 was more abundant in the intestinal mucosa and tumors of Min/+ mice lacking Ahsg, demonstrating increased TGF-beta signaling in vivo. Furthermore, TGF-beta-mediated suppression of immune cell function was exaggerated in Ahsg-/- animals, as shown by inhibition of macrophage activation and reduction in 12-O-tetradecanoylphorbol 13-acetate-induced cutaneous inflammation. Reconstitution of Ahsg-/- mice with bovine Ahsg suppressed endogenous TGF-beta-dependent signaling to wild-type levels, suggesting that therapeutic enhancement of AHSG levels may benefit patients whose tumors are driven by TGF-beta.

Adult↗
PubMed2004

Quality of life in adults diagnosed with familial adenomatous polyposis and desmoid tumor.

PURPOSE: The purpose of this study was to examine the health-related quality of life in a sample of Canadian adults diagnosed with familial adenomatous polyposis and desmoid tumor. METHODS: The study was conducted in two parts. Seven individuals participated in a focus group prior to a mail-out survey. A cross-sectional mail-out survey was administered to eligible individuals who were actively followed at the Familial Gastrointestinal Cancer Registry at Mount Sinai Hospital. RESULTS: Forty-one individuals (25 female and 16 male) were available to be contacted by the registry coordinator and 23 questionnaire packages were completed, resulting in a 56.1 percent participation rate. The results of this study demonstrated a reduced health-related quality of life for individuals living with familial adenomatous polyposis and desmoid tumor for over 10 years. The main predictors of health-related quality of life in this analysis included marital status (married vs. not married), prior knowledge of desmoid tumor in the family, and current level of hopelessness (R(2) = 0.856, df = 13, F = 26.8, P < 0.001). The qualitative content analysis of themes from the focus group indicated that ongoing medical uncertainty and lack of information from health care professionals, isolation, and family communication were the main challenges in living with desmoid tumors. CONCLUSIONS: The findings from this study suggest that ongoing education of health care professionals is warranted and that information and support interventions may be beneficial to this clinical population.

Adenomatous Polyposis Coli↗
PubMed2004

Chromosome 7q31 allelic imbalance and somatic mutations of RAY1/ST7 gene in colorectal cancer.

ST7 is a putative tumor suppressor gene on chromosome 7q31. However, the role of ST7 as a tumor suppressor is uncertain as somatic mutations have been difficult to demonstrate. In order to investigate the genetic role of RAY1/ST7 in tumorigenesis, we have screened 135 colorectal cancers for loss of heterozygosity (LOH) at chromosome 7q31. The entire RAY1/ST7 gene, including intron/exon boundaries and alternate 5' and 3' sequences of 15/124 (12%) informative cancers with LOH were characterized. No somatic mutations of the RAY1/ST7 gene were observed. Our results do not support a role for RAY1/ST7 as a colorectal cancer tumor suppressor gene.

Adenocarcinoma↗
PubMed2004

Prognostic factors in resected pancreatic adenocarcinoma: analysis of actual 5-year survivors.

BACKGROUND: Pancreatic cancer is a rapidly fatal disease with very few 5-year survivors even after aggressive surgical treatment. Our objective was to determine the actual 5-year survival rate of patients with pancreatic adenocarcinoma who underwent a resection with curative intent in 5 teaching hospitals within the University of Toronto system. We then sought to determine clinical and histopathologic features of 5-year survivors to determine factors associated with a favorable prognosis. STUDY DESIGN: A retrospective chart review was performed using surgeon and hospital databases to identify patients who had a surgical resection for pancreatic adenocarcinoma between January 1, 1988, and December 31, 1996. RESULTS: One hundred twenty-three patients who had a resection and a pathologic diagnosis of pancreatic adenocarcinoma with complete followup were identified from seven surgical practices. Mean survival (+/- standard error) in this series was 31.7 +/- 3.5 months (median 13.6 months). There were 18 5-year survivors (14.6%), including 5 patients (4.1%) who survived longer than 10 years. The survivors included 13 patients who had undergone a Whipple resection, 4 who had undergone a distal pancreatectomy, and 1 who had undergone a total pancreatectomy. Tumor size, lack of jaundice at presentation, negative nodal disease, low tumor grade, and a low tumor stage were all significant predictors of survival in univariate analysis (all p < 0.05). Only tumor stage (hazard ratio [95% confidence interval]: stage IIA 1.5 [0.8 to 2.8], stage IIB 2.6 [1.4 to 4.7], stage III 1.8 [0.8 to 4.3]) and tumor grade (hazard ratio [95% confidence interval]: moderately differentiated 1.6 [0.9 to 2.9], and poorly differentiated 3.1 [1.6 to 6.2]) were independently associated with survival differences in a multivariate Cox proportional hazards model. CONCLUSIONS: We conclude that longterm survival from pancreatic adenocarcinoma is possible if the disease is identified in its early stages. These and other similar data should provide further stimulus for the development and evaluation of novel screening strategies to improve early detection of this disease.

Adenocarcinoma↗
PubMed2004

Gastrointestinal cancers and neurofibromatosis type 1 features in children with a germline homozygous MLH1 mutation.

Heterozygous germline DNA mismatch repair gene mutations are typically associated with hereditary nonpolyposis colorectal cancer. The molecular hallmark of this syndrome is high-frequency microsatellite instability in the tumors. Rare childhood cases with homozygous or compound heterozygous DNA mismatch repair gene mutations have a described predisposition to leukemia, lymphoma, and brain tumors but not to gastrointestinal cancer. We have now characterized a family in which 2 children with a homozygous germline DNA mismatch repair gene mutation developed early-onset gastrointestinal cancers. The 11-year-old proband had café-au-lait macules and developed metastatic duodenal adenocarcinoma that arose in a tubulovillous adenoma. His 9-year-old sister with café-au-lait macules and axillary freckling presented with malignant colon polyps. A 6-year-old sister with café-au-lait macules, hairy nevi, and a plexiform neurofibroma of the tongue has no malignancies to date. The family history did not fulfill the Amsterdam criteria for hereditary nonpolyposis colorectal cancer, but 2 relatives in their 60s had gastric cancer and colorectal cancer, whereas the parents, who are first cousins, remain cancer free. The proband's metastatic duodenal cancer and his sister's malignant colon polyps had high-frequency microsatellite instability but had detectable MLH1, MSH2, and MSH6 proteins by immunohistochemistry. Because some germline DNA mismatch repair gene deficiencies are associated with apparently intact immunohistochemical DNA mismatch repair gene expression in tumors, we proceeded to DNA sequencing, which showed that all 3 children had a germline homozygous MLH1 missense mutation (exon 18, codon 687, CGG-->TGG), whereas both parents were heterozygous for this mutation.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Tumor microsatellite-instability status as a predictor of benefit from fluorouracil-based adjuvant chemotherapy for colon cancer.

BACKGROUND: Colon cancers with high-frequency microsatellite instability have clinical and pathological features that distinguish them from microsatellite-stable tumors. We investigated the usefulness of microsatellite-instability status as a predictor of the benefit of adjuvant chemotherapy with fluorouracil in stage II and stage III colon cancer. METHODS: Tumor specimens were collected from patients with colon cancer who were enrolled in randomized trials of fluorouracil-based adjuvant chemotherapy. Microsatellite instability was assessed with the use of mononucleotide and dinucleotide markers. RESULTS: Of 570 tissue specimens, 95 (16.7 percent) exhibited high-frequency microsatellite instability. Among 287 patients who did not receive adjuvant therapy, those with tumors displaying high-frequency microsatellite instability had a better five-year rate of overall survival than patients with tumors exhibiting microsatellite stability or low-frequency instability (hazard ratio for death, 0.31 [95 percent confidence interval, 0.14 to 0.72]; P=0.004). Among patients who received adjuvant chemotherapy, high-frequency microsatellite instability was not correlated with increased overall survival (hazard ratio for death, 1.07 [95 percent confidence interval, 0.62 to 1.86]; P=0.80). The benefit of treatment differed significantly according to the microsatellite-instability status (P=0.01). Adjuvant chemotherapy improved overall survival among patients with microsatellite-stable tumors or tumors exhibiting low-frequency microsatellite instability, according to a multivariate analysis adjusted for stage and grade (hazard ratio for death, 0.72 [95 percent confidence interval, 0.53 to 0.99]; P=0.04). By contrast, there was no benefit of adjuvant chemotherapy in the group with high-frequency microsatellite instability. CONCLUSIONS: Fluorouracil-based adjuvant chemotherapy benefited patients with stage II or stage III colon cancer with microsatellite-stable tumors or tumors exhibiting low-frequency microsatellite instability but not those with tumors exhibiting high-frequency microsatellite instability.

Analysis of Variance↗
PubMed2003

Heterozygosity for the BLM(Ash) mutation and cancer risk.

Bloom syndrome is an autosomal recessive disorder whose characteristics include an increased risk for many types of cancers. In contrast to the homozygous mutations of Bloom syndrome, heterozygous carriers of BLM mutations may be at increased risk for developing colorectal cancer. We have screened 2,333 Jewish individuals, including 497 individuals with colorectal cancer, 125 with adenomatous polyps, 767 with noncolorectal cancers and 944 controls for the truncating BLM(Ash) founder mutation. The BLM(Ash) mutation was carried by 0.80% of individuals with colorectal neoplasia, 0.87% of those with any type of cancer and 0.85% of controls. In addition to case-control data, we found no evidence to support a significant relationship between increased cancer risk and heterozygous BLM(Ash) mutations with respect to age of cancer diagnosis, tumor multiplicity or family cancer history.

Aged↗
PubMed2003

The experience of loss and anticipation of distress in colorectal cancer patients undergoing genetic testing.

OBJECTIVE: The purpose of this paper is to describe pretest psychological functioning in a sample of colorectal cancer (CRC) patients undergoing genetic testing. We also explored the relationship among demographic, medical, family history and loss variables and current pretest distress, and those related to anticipated posttest distress. METHODS: This paper reports pretest findings from a prospective, longitudinal psychosocial survey. Data are presented on 220 CRC patients at pretest. RESULTS: We found a subgroup of CRC patients that are currently distressed and anticipate becoming depressed if they receive a positive genetic test result. There were significant associations among pretest distress, family history of CRC and loss related to CRC and anticipation of becoming depressed at posttest. CONCLUSIONS: The findings suggest that a subgroup of CRC patient's experience or anticipate distress that may warrant attention. Family history of CRC and losses related to CRC may be important indicators of posttest adjustment.

Adaptation, Psychological↗
PubMed2003

Relatives of colorectal cancer patients: factors associated with screening behavior.

BACKGROUND: The purpose of this study was to identify whether decisions regarding colorectal cancer (CRC) screening by relatives of CRC patients are influenced by social interactions with family members, friends, and physicians or by public awareness campaigns. METHODS: Screened (n=236) and nonscreened (n=132) relatives of CRC patients were interviewed in 2001. A socioecologic model was used as the framework for the interview variables, which included interactions with relatives, medical professionals, and social groups, as well as perceived benefits and barriers to screening and perceived susceptibility. RESULTS: Physician encouragement, fewer barriers to screening, strong CRC family history, encouragement from relatives, advice from a surgeon, and discussion of CRC screening with social groups were all associated with ever having been screened. Having been encouraged by a physician was the strongest correlate of screening behavior. Perceived susceptibility to CRC, advice from family members, and exposure to public awareness information were not associated with screening. CONCLUSIONS: The socioecologic framework is a good explanatory model of CRC screening in increased-risk relatives, as variables from each level were associated with screening. These findings can guide interventions aimed at increasing screening uptake, particularly those involving physicians.

Adult↗
PubMed2003

Genotype and phenotype of patients with both familial adenomatous polyposis and thyroid carcinoma.

The incidence of thyroid carcinoma in familial adenomatous polyposis (FAP) is thought to be 1%-2%, with the majority of cases being female. We have investigated the phenotype and genotype of 16 patients with FAP associated thyroid carcinoma. Among 1194 FAP patients studied in two high risk registries in North America (Familial Gastrointestinal Cancer Registry, Toronto and University California, San Francisco), 16 (1.3%) unrelated patients with FAP associated thyroid cancers were identified. Adenomatous polyposis coli (APC) gene testing was performed in 14 of the 16 cases. The average age of diagnosis for FAP and thyroid carcinoma was 29 years (range 17-52 years) and 33 years (range 17-55 years), respectively. All FAP patients except 1 had more than 100 colonic adenomas. Extracolonic manifestations, beside thyroid cancer, were presented in 81% (n = 13) of the patients, including gastric and duodenal polyps, desmoid tumor, osteoma, epidermoid cyst, sebaceous cyst and lipoma. Colorectal cancer was diagnosed in 38% (n = 6) of the patients. The pathology of the FAP associated thyroid cancer was predominantly papillary carcinoma. Germline mutations were identified in 12 of 14 patients tested. Mutations proximal to the mutation cluster region (1286-1513) were detected in 9 cases. Thyroid cancer in our FAP population was rare, predominantly in females and showed papillary carcinoma histology. Additionally, thyroid cancer in our patients occurred in the setting of classic FAP phenotype. Germline mutations were located predominantly outside the APC mutation cluster region.

Adenomatous Polyposis Coli↗
PubMed2003

Msh2 deficiency enhances somatic Apc and p53 mutations in Apc+/-Msh2-/- mice.

Inactivation of the adenomatous polyposis coli (Apc) gene by loss of the wild-type Apc allele (LOH) is a prerequisite for the development of intestinal adenomas in Msh2 proficient Min (Apc+/-Msh2+/+) mice. In contrast, adenomas from Msh2 deficient Min (Apc+/-Msh2-/-) mice are not usually associated with LOH. Given the role of Msh2 in post-replicative DNA repair, this study investigated whether Msh2 deficiency enhances somatic Apc and p53 mutations in Apc+/-Msh2-/- mice. Somatic Apc mutations (5/sample) were observed in the non-neoplastic intestinal mucosa from Apc+/-Msh2-/- mice but not from Min mice, suggesting that Msh2 deficiency is associated with a hypermutable state in the intestinal mucosa from Apc+/-Msh2-/- mice. Adenomas from Apc+/-Msh2-/- mice had a 2-fold higher rate of somatic Apc mutations (10/adenoma) than the non-neoplastic intestinal mucosa (5/sample), and did not demonstrate LOH. Truncating Apc mutations were observed in 82% of the adenomas from Apc+/-Msh2-/- mice and were not observed at all in the non-neoplastic intestinal mucosa. In contrast, in Min mice, all adenomas demonstrated LOH, had significantly less numbers of somatic Apc mutations (1.8 mutations/adenoma) compared with the adenomas from Apc+/-Msh2-/- mice, and harbored no truncating Apc mutations. These observations suggest that somatic Apc mutations, and not LOH, is a likely mechanism by which the Apc gene is inactivated in the development of adenomas in Apc+/-Msh2-/- mice in contrast to Min mice. Adenomas from Apc+/-Msh2-/- mice, but not from Min mice, also harbored somatic p53 mutations (mutation frequency of 45.5%), reflecting hypermutability associated with Msh2 deficiency. The nature and frequency of somatic Apc and p53 mutations in Apc+/-Msh2-/- mice suggest that many genomic sites, in addition to genes containing simple repeated sequences, are at risk of somatic mutations associated with Msh2 deficiency.

Adenoma↗
PubMed2003

Pancreatic resection for metastatic renal cell carcinoma: presentation, treatment, and outcome.

BACKGROUND: The diverse natural history of renal cell carcinoma (RCC) includes metastases to the pancreas, a very unusual site for distant spread of other cancers. Considering the relatively indolent behavior of some cases of metastatic RCC, pancreatic resection is offered to select patients. METHODS: We reviewed the records of patients at three affiliated university hospital centers who had prior nephrectomy for RCC and subsequent pancreatic resection of metastases. RESULTS: Fourteen patients--9 women and 5 men with a median age of 63.8 years--underwent a total of 15 pancreatic resections for metastatic RCC. Nine (64%) had solitary metastases. The median interval from nephrectomy to diagnosis of pancreatic metastases was 83 months. The median size of metastases was 4.6 cm. There was one perioperative death. Pancreatic recurrence occurred in five patients (36%), and one patient underwent repeat resection. At a median follow-up of 32 months, seven patients (50%) are alive without evidence of disease, and four patients (28%) are alive with recurrent disease. CONCLUSIONS: Resection of pancreatic metastases from RCC is associated with long-term survival and should be considered for patients in whom complete resection is possible.

Adult↗
PubMed2003

Agreement between proxy- and case-reported information obtained using the self- administered Ontario Familial Colon Cancer Registry epidemiologic questionnaire.

Case-control studies of fatal cancers often rely on proxy respondents. Therefore, it is important to determine the completeness and accuracy of proxy-reported information. We evaluated proxy reports using the Ontario Familial Colon Cancer Registry epidemiology questionnaire. A proxy questionnaire was completed by spouses or relatives identified by a sample of participating cases. Item non-response and percentage agreement (between case and proxy reports) were assessed. More than 30% of proxies were unable to report on physical activity, gynecological surgery, alcohol intake, weight 20 years ago, and oral contraceptive use. Proxy reports of medical history and bowel screening varied, the percentage missing ranging from 5% for diabetes to 44% for familial polyposis in the case of medical history, and from 4% for colonoscopy to 27% for hemoccult tests in the case of screening. Agreement between case and proxy report was good to excellent for colonic screening, most medical history, and for reproductive, medication and vitamin use variables (74% to 100%). It is useful to collect proxy information on such variables as medical history, parity, colonic screening and vitamin use, whereas oral contraceptive use and previous weight are not well reported.

Case-Control Studies↗
PubMed2003

Distinguishing right from left colon by the pattern of gene expression.

Distinct epidemiological and clinicopathological characteristics of colorectal carcinomas (CRCs) based on their anatomical location suggest different risk factors and pathways of transformation associated with proximal and distal colon carcinogenesis. These differences may reflect distinct biological characteristics of proximal and distal colonic mucosa, acquired in embryonic or postnatal development, that determine a differential response to uniformly distributed environmental factors. Alternatively, the differences in the epidemiology of proximal and distal CRCs could result from the presence of different procarcinogenic factors in the ascending versus descending colon, acting on cells with either similar or distinct biological characteristics. We applied cDNA microarray technology to explore the possibility that mucosal epithelium from adult proximal and distal colon can be distinguished by their pattern of gene expression. In addition, gene expression was studied in fetal (17-24 weeks gestation) proximal and distal colon. More than 1000 genes were expressed differentially in adult ascending versus descending colon, with 165 genes showing >2-fold and 49 genes showing >3-fold differences in expression. With almost complete concordance, biopsies of adult colonic epithelium can be correctly classified as proximal or distal by gene expression profile. Only 87 genes were expressed differently in ascending and descending fetal colon, indicating that, although anatomically relevant differences are already established in embryonic colon, additional changes in gene expression occur in postnatal development.

Adult↗
PubMed2002

Mutation profiling of mismatch repair-deficient colorectal cncers using an in silico genome scan to identify coding microsatellites.

Human colorectal, endometrial, and gastric cancers with defective DNA mismatch repair (MMR) have microsatellite instability, a unique molecular alteration characterized by widespread frameshift mutations of repetitive DNA sequences. We developed "Kangaroo," a bioinformatics program for searches in nucleotide and protein sequence databases, and performed an in silico genome scan for DNA coding microsatellites that may have novel mutations in MMR-deficient cancers. Examination of 29 previously untested coding polyadenines revealed widespread mutations in MMR-deficient colorectal cancers, with the highest frequencies in ERCC5, CASP8AP2, p72, RAD50, CDC25, RECQL1, CBF2, RACK7, GRK4, and DNAPK (range, 10-33%). This algorithm allows comprehensive mutation profiling of MMR-deficient cancers, an important step in understanding the pathogenesis of these neoplasms.

Algorithms↗
PubMed2002

Risk of pancreatic cancer among individuals with a family history of cancer of the pancreas.

In a hospital based case-control study of pancreatic cancer in Ontario and Quebec, a total of 174 incident pancreatic cancer cases and 136 healthy controls were compared for their family history of cancer. Information regarding the ages and sites of cancer was taken for 966 first-degree relatives of the cancer cases and for 903 first-degree relatives of the controls. A total of 150 cancer cases were reported among the relatives of the cases, compared to 122 cases among the relatives of the controls (relative risk 1.15; p = 0.23). Pancreatic cancer was the only site statistically in excess in the case relatives, compared to the control relatives (relative risk = 5.0; p = 0.01). The lifetime risk of pancreatic cancer was 4.7% for the first-degree relatives of the pancreatic cancer cases. The risk was 7.2% for relatives of cases diagnosed before age 60, and was 12.3% for relatives of patients with multiple primary cancers (all ages). These individuals comprise a high-risk group for pancreatic cancer and might benefit from enhanced surveillance or chemoprevention. Familial site-specific pancreatic cancer appears to be a distinct genetic entity, but contributes only modestly to the total burden of pancreatic cancer.

Adult↗
PubMed2002

A population-based study of the extent of surgical resection of potentially curable colon cancer.

BACKGROUND: We attempted to determine factors contributing to the extent of initial curative resection for colon cancer in a population-based cohort. Total abdominal colectomy with ileorectal anastomosis (TAC-IR) may be considered for young patients or those with a colorectal cancer family history to prevent metachronous lesions and facilitate surveillance. METHODS: All Ontario patients newly diagnosed with colon cancer over 12 months beginning in July 1997 were staged at the time of surgery. The extent of resection was compared with variables, including familial risk obtained from the Ontario Familial Colon Cancer Registry. RESULTS: Complete staging was possible for 86% of patients. A total of 1223 patients had a potentially curative resection: 17%, 46%, and 36% were stage I, II, and III, respectively. Patients were more likely to receive a TAC-IR if they were < or = 50 years old (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.8-6.6), if they had a synchronous lesion (OR, 28.37; 95% CI, 12.2-61.2), or if they were at a teaching hospital (OR, 2.8; 95% CI, 1.6-4.7), but not if they had a family history (OR,.7; 95% CI,.3- 1.5). CONCLUSIONS: Young age, teaching hospital, and multiple cancers but not family history were important factors for performing a TAC-IR.

Adult↗