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Francis M Giardiello

Publications and source records attributed to Francis M Giardiello.

At least 19 recordsLinked to original sources
PubMed2006

Prediction of germline mutations and cancer risk in the Lynch syndrome.

CONTEXT: Identifying families at high risk for the Lynch syndrome (ie, hereditary nonpolyposis colorectal cancer) is critical for both genetic counseling and cancer prevention. Current clinical guidelines are effective but limited by applicability and cost. OBJECTIVE: To develop and validate a genetic counseling and risk prediction tool that estimates the probability of carrying a deleterious mutation in mismatch repair genes MLH1, MSH2, or MSH6 and the probability of developing colorectal or endometrial cancer. DESIGN, SETTING, AND PATIENTS: External validation of the MMRpro model was conducted on 279 individuals from 226 clinic-based families in the United States, Canada, and Australia (referred between 1993-2005) by comparing model predictions with results of highly sensitive germline mutation detection techniques. MMRpro models the autosomal dominant inheritance of mismatch repair mutations, with parameters based on meta-analyses of the penetrance and prevalence of mutations and of the predictive values of tumor characteristics. The model's prediction is tailored to each individual's detailed family history information on colorectal and endometrial cancer and to tumor characteristics including microsatellite instability. MAIN OUTCOME MEASURE: Ability of MMRpro to correctly predict mutation carrier status, as measured by operating characteristics, calibration, and overall accuracy. RESULTS: In the independent validation, MMRpro provided a concordance index of 0.83 (95% confidence interval, 0.78-0.88) and a ratio of observed to predicted cases of 0.94 (95% confidence interval, 0.84-1.05). This results in higher accuracy than existing alternatives and current clinical guidelines. CONCLUSIONS: MMRpro is a broadly applicable, accurate prediction model that can contribute to current screening and genetic counseling practices in a high-risk population. It is more sensitive and more specific than existing clinical guidelines for identifying individuals who may benefit from MMR germline testing. It is applicable to individuals for whom tumor samples are not available and to individuals in whom germline testing finds no mutation.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Nasal polyposis in Peutz-Jeghers syndrome: a distinct histopathological and molecular genetic entity.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is an autosomal dominant hamartomatous polyposis syndrome of the gastrointestinal tract, caused by a germline STK11/LKB1 mutation. Nasal polyposis was described in the original report by Peutz. Recently, a molecular-genetic association between nasal polyposis and PJS has been reported. OBJECTIVE: To further explore the occurrence and pathogenesis of PJS-related nasal polyposis. METHODS: 51 patients with PJS, 84 unaffected family members and 36 spouses from 18 families with PJS were questioned for the presence of nasal polyposis. 12 PJS-related nasal polyps, 1 carcinoma of the nasal cavity and 28 sporadic nasal polyps were analysed for loss of (wild type) STK11/LKB1, eosinophilia, squamous metaplasia, dysplasia and expression of cyclo-oxygenase 2 and p53. RESULTS: Nasal polyps occurred in 8 of 51 patients with PJS, and were not reported by non-affected family members (p<0.001). Germline STK11/LKB1 mutations were identified in all patients with PJS and nasal polyposis. Loss of heterozygosity was found in four of eight PJS-related nasal polyps, but not in sporadic nasal polyps (p = 0.002). PJS-related nasal polyps showed less eosinophilia than sporadic nasal polyps (p<0.001). Expression of cyclo-oxygenase 2 was found in 11 of 12 PJS-related nasal polyps and 19 of 28 sporadic nasal polyps (p>0.05). Overexpression of p53 was not found. CONCLUSIONS: Nasal polyposis occurs in a significant number of Dutch patients with PJS, one of whom developed a carcinoma in the nasal cavity. The loss of heterozygosity, and the absence of eosinophilia suggest a distinct pathogenesis compared with sporadic nasal polyposis.

AMP-Activated Protein Kinase Kinases↗
PubMed2006

Combination treatment with curcumin and quercetin of adenomas in familial adenomatous polyposis.

BACKGROUND & AIMS: Familialadenomatous polyposis (FAP) is an autosomal-dominant disorder characterized by the development of hundreds of colorectal adenomas and eventual colorectal cancer. Regression of adenomas in this syndrome occurs with the administration of nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors, but these compounds can have considerable side effects. We evaluated the efficacy of the combination of diet-derived nonprescription supplements curcumin and quercetin to regress adenomas in patients with FAP. METHODS: Five FAP patients with prior colectomy (4 with retained rectum and 1 with an ileal anal pouch) received curcumin 480 mg and quercetin 20 mg orally 3 times a day. The number and size of polyps were assessed at baseline and after therapy. The Wilcoxon signed-rank test was used to determine differences in the number and size of polyps. Treatment side effects and medication compliance also were evaluated. RESULTS: All 5 patients had a decreased polyp number and size from baseline after a mean of 6 months of treatment with curcumin and quercetin. The mean percent decrease in the number and size of polyps from baseline was 60.4% (P < .05) and 50.9% (P < .05), respectively. Minimal adverse side effects and no laboratory abnormalities were noted. CONCLUSIONS: The combination of curcumin and quercetin appears to reduce the number and size of ileal and rectal adenomas in patients with FAP without appreciable toxicity. Randomized controlled trials are needed to validate these findings.

Adenomatous Polyposis Coli↗
PubMed2006

Frequency and spectrum of cancers in the Peutz-Jeghers syndrome.

BACKGROUND: Although an increased cancer risk in Peutz-Jeghers syndrome is established, data on the spectrum of tumors associated with the disease and the influence of germ-line STK11/LKB1 (serine/threonine kinase) mutation status are limited. EXPERIMENTAL DESIGN: We analyzed the incidence of cancer in 419 individuals with Peutz-Jeghers syndrome, and 297 had documented STK11/LKB1 mutations. RESULTS: Ninety-six cancers were found among individuals with Peutz-Jeghers syndrome. The risk for developing cancer at ages 20, 30, 40, 50, 60, and 70 years was 2%, 5%, 17%, 31%, 60%, and 85%, respectively. The most common cancers represented in this analysis were gastrointestinal in origin, gastroesophageal, small bowel, colorectal, and pancreatic, and the risk for these cancers at ages 30, 40, 50, and 60 years was 1%, 9%, 15%, and 33%, respectively. In women with Peutz-Jeghers syndrome, the risk of breast cancer was substantially increased, being 8% and 31% at ages 40 and 60 years, respectively. Kaplan-Meier analysis showed that cancer risks were similar in Peutz-Jeghers syndrome patients with identified STK11/LKB1 mutations and those with no detectable mutation (log-rank test of difference chi2 = 0.62; 1 df; P = 0.43). Furthermore, the type or site of STK11/LKB1 mutation did not significantly influence cancer risk. CONCLUSIONS: The results from our study provide quantitative information on the spectrum of cancers and risks of specific cancer types associated with Peutz-Jeghers syndrome.

AMP-Activated Protein Kinase Kinases↗
PubMed2006

Screening for early pancreatic neoplasia in high-risk individuals: a prospective controlled study.

BACKGROUND & AIMS: Individuals with a strong family history of pancreatic cancer and persons with Peutz-Jeghers syndrome (PJS) have an increased risk for pancreatic cancer. This study screened for early pancreatic neoplasia and compared the pancreatic abnormalities in high-risk individuals and control subjects. METHODS: High-risk individuals with PJS or a strong family history of pancreatic cancer were prospectively evaluated with baseline and 12-month computed tomography (CT) scan and endoscopic ultrasonography (EUS). If EUS was abnormal, EUS-fine-needle aspiration and endoscopic retrograde cholangiopancreatography (ERCP) were performed. Surgery was offered to patients with potentially neoplastic lesions. Radiologic findings and pathologic diagnoses were compared. Patients undergoing EUS and/or ERCP for benign non-pancreatic indications were concurrently enrolled as control subjects. RESULTS: Seventy-eight high-risk patients (72 from familial pancreatic cancer kindreds, 6 PJS) and 149 control patients were studied. To date, 8 patients with pancreatic neoplasia have been confirmed by surgery or fine-needle aspiration (10% yield of screening); 6 patients had 8 benign intraductal papillary mucinous neoplasms (IPMNs), 1 had an IPMN that progressed to invasive ductal adenocarcinoma, and 1 had pancreatic intraepithelial neoplasia. EUS and CT also diagnosed 3 patients with 5 extrapancreatic neoplasms. At EUS and ERCP abnormalities suggestive of chronic pancreatitis were more common in high-risk patients than in control subjects. CONCLUSIONS: Screening EUS and CT diagnosed significant asymptomatic pancreatic and extrapancreatic neoplasms in high-risk individuals. IPMN should be considered a part of the phenotype of familial pancreatic cancer. Abnormalities suggestive of chronic pancreatitis are identified more commonly at EUS and ERCP in high-risk individuals.

Adult↗
PubMed2006

Peutz-Jeghers syndrome and management recommendations.

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disease caused by germline mutation of the serine threonine kinase 11 and characterized by hamartomatous polyps in the gastrointestinal tract and mucocutaneous melanin pigmentation. Patients with PJS are at increased risk for common and unusual types of gastrointestinal and nongastrointestinal tumors. This review analyzes currently available literature and describes the clinical characteristics of PJS, assesses the risk of malignancy in this disorder, and delineates management and surveillance recommendations for affected individuals.

AMP-Activated Protein Kinase Kinases↗
PubMed2005

Clinicopathological features and microsatellite instability (MSI) in colorectal cancers from African Americans.

African Americans (AAs) have a 1.5 times higher risk of colorectal carcinoma (CRC) than Caucasians. Gene silencing through CpG island hypermethylation has been associated with the genesis or progression of microsatellite instability (MSI) largely due to 1 target for hypermethylation being the DNA mismatch repair gene hMLH1; there is anecdotal evidence of an increased incidence of MSI among AAs. P16 and hMLH1 can be inactivated by hypermethylation of their respective promoter regions, abrogating the ability to regulate cell proliferation and repair processes. We studied such methylation, as well as hMHS2 expression in colorectal cancers from AA patients to determine if MSI is associated with epigenetic silencing. Experiments were conducted on matched normal and colon cancer tissues from AA patients (n = 51). A total of 5 microsatellite markers (D2S123, D5S346, D17S250, BAT25 and BAT26) were used to evaluate MSI status. P16 and hMLH1 promoter methylation status was determined following bisulfite modification of DNA and using methylation specific PCR, while immunohistochemistry (IHC) was used to examine expression of hMLH1 and hMSH2. A total of 22 (43%) cancers demonstrated microsatellite instability-high (MSI-H), while 27 were microsatellite stable (MSS) and 2 were microsatellite instability-low (MSH-L). Most of the MSI-H tumors were proximal, well differentiated and highly mucinous. Most patients in the MSI-H group were females (68%). The p16 promoter was methylated in 19 of 47 (40%) tumors. A total of 7 of these CRCs demonstrated MSI-H (33%). The hMLH1 promoter was methylated in 29 of 34 (85%) tumors, of which 13 CRCs demonstrated MSI-H (87%). hMLH1 and hMSH2 staining was observed in 66% and 38% of MSI-H tumors, respectively. Overall, the prevalence of MSI-H colorectal tumor was 2-3-fold higher, while the defect in the percentage expression of mismatch repair (MMR) genes (hMLH1 and hMSH2) was similar in AA patients compared to the U.S. Caucasian population. Similar numbers of AA MSS tumors with p16 and hMLH1 methylation likely indicate hemimethylation of genes that might reflect environmental or genetic influences that might be more common in the AA population.

Adaptor Proteins, Signal Transducing↗
PubMed2005

Increased cyclooxygenase-2 expression in duodenal compared with colonic tissues in familial adenomatous polyposis and relationship to the -765G -> C COX-2 polymorphism.

BACKGROUND: Colorectal cancers arising in patients with familial adenomatous polyposis (FAP) can be largely prevented by polyp surveillance and prophylactic colectomy. As a result, duodenal adenocarcinoma has become a leading cause of death in patients with FAP. Cyclooxygenase 2 (COX-2) inhibition is effective against colorectal polyposis in FAP, but is less effective in treating duodenal polyps. We compared the expression of COX-2 in duodenal and colorectal adenomas from patients with FAP and from patients with sporadic neoplasms and correlated expression to a COX-2 promoter polymorphism (-765G/-->C) that is reported to influence COX-2 expression. METHODS: The study population included 36 FAP patients with colonic adenomas, 22 FAP patients with duodenal adenomas, 22 patients with sporadic duodenal adenomas, and 17 patients with sporadic duodenal adenocarcinoma. Neoplastic and corresponding normal tissue COX-2 expressions were determined using immunohistochemistry on tissue microarrays. The prevalence and ethnic distribution of a polymorphism in the COX-2 promoter that influences COX-2 expression (-765G --> C) were determined in DNA from 274 individuals by real-time quantitative PCR. RESULTS: Among patients with FAP, histologically normal duodenal mucosa showed higher COX-2 expression than normal colonic mucosa (P < 0.02), and duodenal adenomas had higher COX-2 expression than colonic adenomas (P </= 0.01). In addition, the normal duodenum of patients with FAP showed higher COX-2 expression than the normal duodenal mucosa of patients with sporadic adenomas (P < 0.05). COX-2 expression was significantly higher in the normal-appearing (P < 0.01) mucosa of patients with FAP carrying the -765GG genotype compared with those carrying the -765GC or -765CC genotypes. The -765C genotype was more common in African Americans than in Caucasians (52% versus 33%, P < 0.01). CONCLUSIONS: High COX-2 expression in the normal and adenomatous duodenal mucosa of patients with FAP may explain the poorer response of these neoplasms to chemoprevention with COX-2 inhibitors.

Adenoma↗
PubMed2005

Oral contraceptives and polyp regression in familial adenomatous polyposis.

Epidemiologic and experimental reports suggest that female hormones protect against the development of colorectal cancer, but studies are limited. We describe a patient in the placebo arm of a 4-year primary chemoprevention trial who developed adenomatous polyps and then had eradication of polyps after the administration of oral contraceptives. No change in the prostaglandin levels in the colonic mucosa was noted after polyp elimination, making nonsteroidal anti-inflammatory drug ingestion unlikely as a cause. This report represents the regression of colorectal adenomas with the use of estrogen/progesterone compounds.

Adenomatous Polyposis Coli↗
PubMed2005

Positive correlation of insulin-like growth factor-II with proliferating cell index in patients with colorectal neoplasia.

BACKGROUND: Insulin-like growth factor-II (IGF-II) stimulates cell proliferation and is considered a potential risk factor for colorectal cancer. Tumor levels of IGF-II seem to positively correlate with colorectal cancer cell proliferation. This investigation examined the association of circulating IGF-II to the proliferating cell index (PCI) of tumor and matched normal mucosa in patients with colorectal neoplasia. METHODS: Circulating IGF-II level (ng/mL) was determined in the peripheral blood plasma by ELISA. The proliferating cells in tumor or matched normal mucosa were immunohistochemically stained using the primary antibody against Ki-67. Computer image analysis was used and PCI was expressed as the percentage of Ki-67-positive cells/total counted cells. RESULTS: Sixty-four patients were evaluated; 45 had colorectal neoplasia (27 males/18 females; mean age, 66.8 +/- 11.8 years) and 19 had hyperplastic polyps (6 males and 13 females; mean age, 58.4 +/- 14.4 years). Among patients with colorectal neoplasia, blood IGF-II levels were positively correlated with PCI in the matched normal mucosa (r = 0.46, P < 0.05) but not in the tumor. In patients with hyperplastic polyps, blood IGF-II levels were not correlated with the PCI in the polyps. Blood IGF-II levels were higher in colorectal cancer patients with Dukes' C/D stage (P < 0.01) or with positive lymph nodes (P < 0.01). CONCLUSION: Circulating IGF-II positively correlated with PCI in normal colonic mucosa of patients with colorectal neoplasia, suggesting that IGF-II may have a role in initiating the carcinogenic pathway by stimulating cell proliferation. Blood IGF-II was increased in advanced colorectal cancer, indicating that it might enhance colorectal cancer progression and be a useful marker of poor prognosis.

Aged↗
PubMed2005

Sulindac inhibits beta-catenin expression in normal-appearing colon of hereditary nonpolyposis colorectal cancer and familial adenomatous polyposis patients.

Sulindac reduces colorectal cancer risk in genetically susceptible humans and animals. The molecular mechanisms underlying these effects are incompletely understood. Many studies suggest an important role for induction of apoptosis involving the mitochondrial pathway and the death receptor pathway. Alternatively, mechanisms involving the APC-beta-catenin-Wnt pathway have been suggested, possibly mediated by p21. We determined the effects of sulindac on apoptosis and expression of death receptor (DR)-4 and DR5, beta-catenin, and p21 in normal-appearing colorectal epithelium. Biopsies were obtained before and after sulindac treatment during two chemoprevention studies. Patients (n = 18) with hereditary nonpolyposis colorectal cancer (HNPCC) received 150 mg sulindac bd for 4 weeks in a placebo-controlled crossover design. Patients (n = 6) with familial adenomatous polyposis (FAP) received 150 mg sulindac bd for 6 months. Apoptosis was assessed by M30 staining and expression patterns of DR4, DR5, beta-catenin, and p21 were studied immunohistochemically. In HNPCC patients, apoptotic indices were similar following placebo and sulindac. Also in FAP patients, apoptotic indices were not different after sulindac compared with pretreatment values. Expression of DR4 and DR5 was observed in all samples with no consistent differences between placebo/baseline and sulindac. Intensity of membranous beta-catenin staining was lower in HNPCC samples following sulindac compared with placebo (P < 0.001). Similar results were obtained in FAP samples (P < 0.01). p21 expressions before and after sulindac treatment were similar in both patient groups. In conclusion, sulindac inhibits beta-catenin expression in normal colorectal epithelium from HNPCC and FAP patients without affecting apoptotic indices and DR4, DR5, and p21 expression.

Adenomatous Polyposis Coli↗
PubMed2005

Genetic polymorphisms of flavin monooxygenase 3 in sulindac-induced regression of colorectal adenomas in familial adenomatous polyposis.

Sulindac is a nonsteroidal antiinflammatory drug with a chemopreventive effect in patients with familial adenomatous polyposis (FAP). In vivo, the active form of sulindac is sulindac sulfide, which is inactivated by the hepatic microsomal enzyme, flavin monooxygenase 3 (FMO3). In humans, numerous polymorphisms exist in FMO3, which alter enzymatic activity and subsequent substrate metabolism. We recently showed that certain polymorphic forms of FMO3 with reduced activity were associated with a more favorable response to sulindac in preventing the formation of adenomas in patients with FAP without polyps at baseline. Here, we determined whether these FMO3 polymorphisms correlated with the ability of sulindac to regress polyposis in patients with FAP who had polyps prior to treatment. Nineteen patients were treated with 150 mg sulindac twice a day for 6 months. The size and number of polyps in each patient was assessed at baseline (prior to the administration of sulindac), and at 3 and 6 months. Genotyping was done on seven established FMO3 polymorphisms with functional significance-M66I, E158K, P153L, V257M, E305X, E308G, and R492W. Statistical analyses were done with Wilcoxon rank sum test. Of the loci examined, only E158K and E308G showed polymorphic changes. Six patients exhibited polymorphisms in both E158K and E308G loci and were designated as genotype combination 1. The remaining patients were designated as genotype combination 2. Over the course of treatment, patients with genotype combination 1 had a greater reduction in both the size and number of polyps than those with genotype combination 2. These results suggest that combined polymorphic changes in the E158K and E308G alleles may protect against polyposis in patients with FAP treated with sulindac.

Adenoma↗
PubMed2004

Genetic polymorphisms of human flavin monooxygenase 3 in sulindac-mediated primary chemoprevention of familial adenomatous polyposis.

PURPOSE: Sulindac is a nonsteroidal anti-inflammatory drug (NSAID) effective in regressing adenomas in patients with familial adenomatous polyposis (FAP). However, a recent randomized trial showed that sulindac, when compared with placebo, failed to prevent the development of adenomatous polyps in genotypically positive but phenotypically negative FAP patients. The present study determined whether polymorphisms in the gene encoding flavin monooxygenase 3 (FMO3), a hepatic microsomal enzyme that inactivates sulindac, played a role in determining the efficacy of sulindac in preventing polyposis in this cohort of FAP patients. EXPERIMENTAL DESIGN: Genotyping was performed on seven established FMO3 polymorphisms previously shown to have functional relevance-M66I, P153L, E158K, V257M, E305X, E308G, and R492W-in 21 and 20 FAP patients, who received sulindac and placebo, respectively. RESULTS: None of the 41 patients exhibited heterozygous or homozygous M66I and R492W variant alleles, or homozygous P153L, V257M, and E305X variant alleles. Among sulindac-treated patients who did not develop adenomas ("responders"), 4 (33%) were homozygous for E158K and 2 (17%) were homozygous for E308G variant alleles. In contrast, none of the patients on sulindac who developed adenomas ("nonresponders") exhibited homozygosity for either of the two variant alleles. In addition, polymorphisms in the E158K or E308G allele were associated with a significant reduction in mucosal prostanoid levels in patients treated with sulindac. CONCLUSIONS: Polymorphisms in FMO3, particularly at the E158K and E308G loci, may reduce activity in catabolizing sulindac and result in an increased efficacy to prevent polyposis in FAP.

Adenomatous Polyposis Coli↗
PubMed2004

Screening for pancreatic neoplasia in high-risk individuals: an EUS-based approach.

BACKGROUND & AIMS: Relatives of patients with pancreatic cancer and persons with certain inherited syndromes are at increased risk for developing pancreatic cancer. We prospectively evaluated the feasibility of screening for pancreatic neoplasia in high-risk individuals. METHODS: Individuals from familial pancreatic cancer kindreds and a patient with Peutz-Jeghers syndrome underwent screening endoscopic ultrasound (EUS). If the EUS was abnormal, EUS-guided fine-needle aspiration, endoscopic retrograde cholangiopancreatography (ERCP), and spiral computed tomography (CT) were performed. Patients with abnormalities suggesting neoplasia had surgery. RESULTS: Thirty-eight patients were studied; 31 (mean age, 58 yr; 42% men) from kindreds with > or =3 affected with pancreatic cancer; 6 from kindreds with 2 affected relatives, 1 was a patient with Peutz-Jeghers syndrome. None had symptoms referable to the pancreas or suggestive of malignancy. Six pancreatic masses were found by EUS: 1 invasive ductal adenocarcinoma, 1 benign intraductal papillary mucinous neoplasm, 2 serous cystadenomas, and 2 nonneoplastic masses. Hence, the diagnostic yield for detecting clinically significant pancreatic neoplasms was 5.3% (2 of 38). The 1 patient with pancreatic cancer was treated and still is alive and disease-free >5 years after surgery. EUS changes similar to those associated with chronic pancreatitis were found, which were more common in patients with a history of regular alcohol intake (P = 0.02), but also occurred in patients who did not consume alcohol. Screening also led to a new diagnosis and treatment of symptomatic upper-gastrointestinal conditions in 18.4% of patients. CONCLUSIONS: EUS-based screening of asymptomatic high-risk individuals can detect prevalent resectable pancreatic neoplasia but false-positive diagnoses also occur.

Age Distribution↗
PubMed2004

Prostanoids, ornithine decarboxylase, and polyamines in primary chemoprevention of familial adenomatous polyposis.

BACKGROUND & AIMS: Familial adenomatous polyposis because of germline mutation of the adenomatous polyposis coli gene is characterized by development of colorectal adenomas and, ultimately, colorectal cancer. The usefulness of colorectal mucosal compounds to predict the effect on adenoma development of primary chemoprevention with the nonsteroidal anti-inflammatory drug sulindac was evaluated. METHODS: A randomized, double-blind, placebo-controlled study of 41 subjects genotypically affected with familial adenomatous polyposis but phenotypically unaffected was conducted. Patients received either sulindac or placebo for 48 months, and development of new adenomas was evaluated. The levels of 5 prostanoids, ornithine decarboxylase, and polyamines were measured serially in normal-appearing rectal mucosa. RESULTS: There were no statistically significant differences between treatment groups in baseline levels of prostanoids, ornithine decarboxylase, or polyamines. At conclusion of the study, 4 of 5 prostaglandin levels were statistically significantly lower in the sulindac group than in the placebo group. Among the subset of patients taking sulindac, 3 of 5 prostaglandin levels were statistically significantly lower in patients who were polyp free than in those who developed polyps. By contrast, there were no statistically significant differences in ornithine decarboxylase or polyamines between treatment groups or in those on sulindac who were polyp free compared with those who developed polyps. CONCLUSIONS: Colorectal mucosal prostaglandin levels, but not ornithine decarboxylase or polyamines, may be valuable biomarkers to assess appropriate drug dosage and medication compliance in patients undergoing primary chemoprevention therapy with sulindac. Reduction of mucosal prostaglandin levels may be necessary to achieve chemopreventive benefit from this agent.

Adenomatous Polyposis Coli↗
PubMed2004

Loss of imprinting of insulin growth factor II gene: a potential heritable biomarker for colon neoplasia predisposition.

BACKGROUND & AIMS: Loss of genomic imprinting (LOI) of insulin-like growth factor II gene (IGF2) involves abnormal activation of the normally silent maternally inherited allele. LOI of IGF2 has been associated with personal and family history of colorectal neoplasia (CRN), supporting a role for LOI in colorectal carcinogenesis. Whether LOI of IGF2 is associated with known environmental risk factors for CRN is unknown. METHODS: We performed quantitative hot-stop PCR for imprinting analysis of IGF2 on normal peripheral blood lymphocytes (PBL) of individuals. Environmental exposures including tobacco, alcohol, NSAIDs, and nutrient consumption (calcium, folate, selenium, fiber, and fat) were correlated with LOI expression in PBL. Odds ratios (OR) and 95% CI were calculated. RESULTS: The prevalence of LOI of IGF2 was examined in 172 individuals. Persons with CRN (adenomas/cancer) had 5.1-fold (95% CI: 1.92-13.6) increased risk of having LOI of IGF2 in PBL compared with those without CRN. In contrast, tobacco smoking (OR = 0.96, 95% CI: 0.36-2.55), alcohol consumption (OR = 1.22, 95% CI: 0.45-3.3), and NSAIDs use (OR = 1.21, 95% CI: 0.38-3.94) were not significantly associated with LOI of IGF2. Nutrient ingestion including calcium (P = 0.61), folate (P = 0.23), selenium (P = 0.19), fiber (P = 0.63), and fat (P = 0.14) was not statistically correlated with LOI of IGF2. CONCLUSIONS: Abnormal imprinting of IGF2 gene was strongly associated with CRN but not with any of the environmental exposures examined. LOI of IGF2 does not appear to be an environmentally acquired phenomenon but rather a hereditary risk factor for CRN.

Adenoma↗
PubMed2004

Relative frequency and morphology of cancers in STK11 mutation carriers.

BACKGROUND & AIMS: There is limited data on the spectrum and risk for cancer associated with germline serine/threonine protein kinase 11 (STK11) mutations that cause Peutz-Jeghers syndrome (PJS). METHODS: We analyzed the incidence of cancer in 240 individuals with PJS possessing germline mutations in STK11. RESULTS: Fifty-four cancers were found among carriers. Overall, the risk for developing cancer at ages 20, 30, 40, 50, 60, and 70 years was 1%, 3%, 19%, 32%, 63%, and 81%, respectively. Kaplan-Meier analysis showed similar cancer risks between missense and truncating mutation carriers (log-rank chi(2) = 2.48; P = 0.12). There was some evidence that mutations in exon 3 of STK11 were associated with a higher cancer risk than mutations within other regions of the gene. We found no difference in overall cancer risk between male and female carriers (log-rank chi(2) = 1.31; P = 0.25) or between familial and sporadic cases (log-rank chi(2) = 1.16, with 1 df; P = 0.28). The most common cancers represented were gastrointestinal in origin--gastroesophageal, small bowel, colorectal, and pancreatic--and the risk for these cancers at ages 30, 40, 50, and 60 years was 1%, 10%, 18%, and 42%, respectively. In women, the risk for breast cancer was substantially increased, being 32% by age 60 years. CONCLUSIONS: These results quantitatively show the spectrum of cancer risk associated with STK11 germline mutations in the context of PJS and provide a valuable reference for defining surveillance regimens.

AMP-Activated Protein Kinase Kinases↗