Hypertriglyceridemia is positively correlated with the development of colorectal tubular adenoma in Japanese men

The Relationship Between Serum Lipids and the Formation of Colorectal Polyps

BACKGROUND AND AIMS

Obesity, metabolic syndrome, and hyperlipidemia are known as risk factors for colorectal tumors. Colorectal polyps are accepted as potential precursors of colorectal cancer (CRC). This study was designed to clarify the association between the levels of serum lipids and the presence of colorectal polyps.

METHODS

This study was conducted at Basaksehir Cam and Sakura City Hospital, Gastroenterological Surgery Clinic, Istanbul, Turkey. We retrospectively analyzed patients who underwent colonoscopy with serum lipid profile within one month for a one-year period. Groups were analyzed in terms of the correlation between hyperlipidemia and the formation of polyps. The study group was also evaluated in terms of the polyp type, localization, and number.

RESULTS

Among 453 patients, females were 248 and males were 211, with a mean age of 56.7. The study and control groups involved 259 and 194 patients, respectively. The age and serum levels of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglyceride (TG) were found to be statistically significant in terms of polyp presence and number (p < 0.05).

CONCLUSION

Colorectal polyps are well-known precursors of CRC. We found that the combination of elevated serum levels of low-density lipoprotein cholesterol, total cholesterol, and triglycerides may be a risk predictor for the presence of colorectal polyps, which can be advantageous in cancer screening.

Chemoprevention for Colorectal Cancers: Are Chemopreventive Effects Different Between Left and Right Sided Colorectal Cancers?

BACKGROUND AND AIMS

Recent studies have suggested that right- and left-sided colorectal cancers (CRCs) are molecularly distinct. In this study, we examined the association between the risk of right- and left-sided CRC and drug use to estimate their chemopreventive effects METHODS: This multicenter retrospective cohort study was conducted using the data of hospitalized patients between 2014 and 2019 from nine hospital databases. The primary outcomes were right- and left-sided CRC. We evaluated the association of CRCs with drug use and clinical factors. Odds ratios adjusted for age, sex, Charlson Comorbidity Index scores, and smoking status were calculated. We also compared the transcriptional profiling in precancerous lesions, including sessile serrated lesions (SSLs) RESULTS: A total of 307,938 patients, including 2745 with right-sided CRC and 4819 with left-sided CRC, were analyzed. The use of nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, cyclooxygenase-2 inhibitors, and steroids was associated with a lower risk of both right- and left-sided CRCs. In contrast, statins, other lipid-lowering agents, and metformin were associated with a lower risk of left-sided CRC. Transcriptomic analysis showed that SSL, which predominantly develops in the right colon, was associated with a lower expression of lipid metabolism-related genes.

CONCLUSIONS

Targeting lipid metabolism may be useful for chemoprevention of left-sided CRCs, while development of right-sided CRCs may be independent of this pathway.

The relationship between serum lipid levels and colorectal serrated lesions: A systematic review and meta-analysis

Objective: To clarify the relationship between colorectal serrated lesions and serum lipid levels, and provide a scientific basis for the identification and early clinical prevention and treatment of populations that are at risk for colorectal serrated lesions.

Methods: Studies comparing serum lipid levels in patients with colorectal serrated lesions and controls were searched in PubMed, Embase, Web of Science, the Cochrane Library, China Biomedical Literature Database, CNKI, Wanfang Database, and VIP Database. Relevant literature was screened according to the inclusion and exclusion criteria. The mean and standard deviation of the serum lipid levels in patients and controls were extracted from the included literature. The combined weighted mean difference (WMD) and 95% confidence intervals (CIs) were calculated using Review Manager 5.0 software to evaluate the relationship between serum lipid levels and colorectal serrated lesions. Publication bias of the included studies was evaluated by the Egger test.

Results: Twenty-three studies were included, comprising 2,063 patients and 63,909 controls. The serum high-density lipoprotein cholesterol (HDL-C) levels in the case group was significantly lower than in the control group (WMD = −0.122 mmol/L, 95% CI: 0.170–0.073). Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and serum triglyceride levels in the case group were significantly higher than in the control group, and the WMDs were 0.180 mmol/L (95% CI: 0.061–0.299), 0.155 mmol/L (95% CI: 0.038–0.273), and 0.241 mmol/L (95% CI: 0.181–0.302), respectively.

Conclusion: Colorectal serrated lesions may be related to blood lipid levels. Hyperlipidemia might be a risk factor for colorectal serrated lesions.

Is periodontitis a risk factor of benign or malignant colorectal tumor? A population-based cohort study

OBJECTIVE

To examine the risk of developing benign or malignant colorectal tumors in patients with periodontitis within 15 years using Taiwan's National Health Insurance Database.

BACKGROUND

Studies have shown that colorectal carcinoma often develops under inflammatory conditions and changes of microbiota in the gut. Recently, a link between Fusobacterium nucleatum, a periodontal pathogen, and colorectal carcinoma has been proposed. However, whether periodontitis is a risk of developing colorectal tumor remains uncertain.

METHODS

In total, 35 124 participants were enrolled from 2000 to 2015 to examine the development risk of benign colorectal tumors, including 11 708 patients with periodontitis who received therapy (group 1), 11 708 patients with periodontitis not receiving periodontal treatment (group 2), and 11 708 non-periodontitis controls after matching for gender, age, and index year. To examine the risk of developing colorectal malignancy, 11 720 participants were assigned to each of the three groups. Cox proportional hazards model and Kaplan-Meier methods were used to compare the risks. Sensitivity analysis was performed, excluding the diagnoses during the first 1 or 5 years.

RESULTS

After the follow-up, 177, 154, and 63 participants in group 1, group 2, and control group had benign colorectal tumors. Patients with periodontitis tended to be associated with a greater rate of having a benign colorectal tumor. The adjusted hazard ratios (aHRs) were 3.77 (95% confidence interval [CI] 2.01-4.82, p < .001) and 2.85 (95% CI 1.62-3.74, p < .001) for groups 1 and 2, respectively. Regarding the risk of malignant colorectal tumor, 20, 18, and 14 participants who developed malignant tumors were included in group 1, group 2, and control group; however, no significant increase in malignancy was observed in periodontitis groups (aHR1.92, 95% CI 0.74-2.36, p = .482; aHR 1.50, 95% CI 0.68-1.97, p = .529, for the two periodontitis groups, respectively).

CONCLUSIONS

The results of this study suggest that patients with periodontitis may have an increased risk of developing benign, but not malignant, colorectal tumors.

Role of Lipids and Apolipoproteins in Predicting the Prognosis of Hepatocellular Carcinoma After Resection

Purpose

To further clarify the association between abnormal levels of serum lipid components as the main features of dyslipidaemia and hepatocellular carcinoma, which remains unclear.

Patients and Methods

We examined the serum level of lipids and apolipoproteins pattern in 471 patients undergoing curative resection for HCC, 193 patients with chronic liver disease, and 104 patients with benign liver diseases. We performed uni- and multivariate analyses to evaluate the predictive roles of lipids and apolipoproteins for recurrence and survival of HCC in a training cohort of 242 patients and then validated in a cohort of 229 patients.

Results

The majority circulating lipid and apolipoprotein levels such as ApoA1, HDL, and LDL in chronic liver disease and HCC were slightly significantly decreased as compared to those in benign lesion. But no significant differential expression patterns of lipids and apolipoproteins were observed between chronic liver hepatitis and HCC. Multivariable analysis identified ApoA1 as a key parameter related to recurrence and survival in both training and validation cohorts. Moreover, we further demonstrated that low ApoA1 was an independent prognostic factor of poor early recurrence in two cohorts.

Conclusion

Although the alterations of circulating lipids and apolipoproteins were observed in HCC, none of lipids or apolipoproteins could serve as a diagnostic marker. Serum ApoA1 merits consideration as a novel prognostic marker for patients with HCC undergoing surgery since it predicts early recurrence and survival, especially for early stage patients and may improve the prognostic stratification of patients for clinical management and promote HCC clinic outcomes.

Elevated serum triglyceride predicts recurrence of colorectal polyps in patients with advanced adenomas

Background

Recurrence of colorectal polyps is common and impacted by various factors. This study was performed to explore the association between lipid profiles and recurrence of colorectal polyps.

Methods

This study retrospectively analyzed the lipid profiles of 435 patients who underwent colonoscopy with removal of colorectal polyps and assessed recurrence of polyps by follow-up colonoscopy. Multivariate regression logistic analysis was used to evaluate the association between lipid profiles and polyp recurrence.

Results

During the 1.5-year follow-up, recurrence of colorectal polyps was observed in 135 of 435 patients (30.34%). Patients with recurrent polyps showed a higher level of triglycerides (P = 0.006) and lower levels of high-density lipoprotein cholesterol (P = 0.008) and apolipoprotein A1 (P = 0.033). The multivariate regression logistic model suggested that an elevated triglyceride level was an independent risk factor for polyp recurrence (odds ratio, 1.55; 95% confidence interval, 1.02–2.35; P = 0.039) in patients with advanced adenoma.

Conclusions

Lipid profiles are associated with recurrence of colorectal polyps. An elevated triglyceride level is an independent risk predictor of polyp recurrence in patients with advanced adenoma.

Metabolic syndrome is a risk factor for colorectal adenoma and cancer: a study in a White population using the harmonized criteria

BACKGROUND

Metabolic syndrome (MetS) has been associated with colorectal adenomas and cancer. However, MetS definitions have changed over time, leading to a heterogeneity of patients included in previous studies and a substantial inextensibility of observations across time or eastern and western populations. Our aim was to evaluate the association of 'harmonized' criteria-defined MetS and its individual components with colorectal neoplasia and cancer in a western population.

METHODS

In this multicenter, cross-sectional study, we prospectively evaluated consecutive outpatients who underwent open-access colonoscopy over a 3-month period. MetS was diagnosed according to the 2009 'harmonized' criteria.

RESULTS

Out of 5707 patients enrolled, we found 213 cancers (3.7%), 1614 polyps (28.3%), 240 nonpolypoid lesions (4.2%), 95 laterally spreading tumors (1.6%). Polyps presented histological low-grade dysplasia in 72.9% of samples, while in 9.8%, high-grade dysplasia or in situ carcinoma was present; dysplasia rates for nonpolypoid lesions were 66.2% (low-grade) and 2.9% (high-grade/in situ carcinoma), while for laterally spreading tumors, 29.6% and 37%, respectively. Overall, MetS prevalence was 41.6%. MetS correlated with both adenomas [odds ratio (OR): 1.76, 95% confidence interval (CI) 1.54-2.00] and cancer (OR: 1.92, 95% CI 1.42-2.58). MetS was the only risk factor for such colonic lesions in subjects younger than 50 years. For all colonic neoplasia, we found MetS and not its individual components to be significantly associated.

CONCLUSIONS

MetS is risk factor for cancer and adenoma in Whites, especially when younger than 50 years. MetS patients might be considered as a high-risk population also in colorectal cancer screening programs.

Identification of risk factors for sessile and traditional serrated adenomas of the colon by using big data analysis

BACKGROUND AND AIM

Little is known about the risk factors associated with serrated polyps, because the early studies, which occurred before the new World Health Organization classification was introduced, included mixtures of serrated polyps. This study aimed to evaluate the risk factors associated with the presence of sessile serrated adenomas (SSAs) and traditional serrated adenomas (TSAs) using big data analytics.

METHODS

Using a case-control design, we evaluated the risk factors associated with the presence of SSAs and TSAs. Subjects who underwent colonoscopies from 2002 to 2012 as part of the comprehensive health screening programs undertaken at the Samsung Medical Center, Korea, participated in this study.

RESULTS

Of the 48 677 individuals who underwent colonoscopies, 183 (0.4%) had SSAs and 212 (0.4%) had TSAs. The multivariate analysis determined that being aged ≥ 50 years (odds ratio [OR] 1.91, 95% confidential interval [CI] 1.27-2.90, P = 0.002) and a history of colorectal cancer among first-degree relatives (OR 3.14, 95% CI 1.57-6.27, P = 0.001) were significant risk factors associated with the presence of SSAs and that being aged ≥ 50 years (OR 2.61, 95% CI 1.79-3.80, P < 0.001), obesity (OR 1.63, 95% CI 1.12-2.36, P = 0.010), and a higher triglyceride level (OR 1.63, 95% CI 1.12-2.36, P = 0.010) were independent risk factors associated with the presence of TSAs.

CONCLUSIONS

We used big data analytics to determine the risk factors associated with the presence of specific polyp subgroups, and individuals who have these risk factors should be carefully scrutinized for the presence of SSAs or TSAs during screening colonoscopies.

Gallbladder stones and gallbladder polyps associated with increased risk of colorectal adenoma in men

BACKGROUND AND AIMS

Most cases of colorectal cancer develop via an adenoma to carcinoma sequence. Gallbladder polyps share some risk factors with colorectal polyps. Little is known about the relationship between gallbladder diseases and different status of colorectal polyps by gender. This study was to investigate the association of gallbladder stones and polyps with colorectal adenomas by gender in a Taiwanese population.

METHODS

A total of 7066 eligible subjects who underwent a total colonoscopy as a part of health check-up between January 2001 and August 2009 were recruited. Colonoscopic findings were classified into polyp-free, non-neoplastic polyps and colorectal adenomas. Gallbladder stones and gallbladder polyps were diagnosed based on ultrasonographic findings.

RESULTS

There was a significant difference in the status of colon polyps between subjects with and without gallbladder polyps. However, the status of colon polyps was not significantly different between subjects with or without gallbladder stones. After adjusting obesity, fasting plasma glucose, and other variables, there was a positive relationship between gallbladder polyps and colorectal adenomas (odds ratio [OR]: 1.396, 95% confidence interval [CI]: 1.115-1.747) but not non-neoplastic polyps in all subjects. In men, gallbladder polyps (OR: 1.560, 95% CI: 1.204-2.019) and gallbladder stones (OR: 1.465, 95% CI 1.081-1.984) were positively associated with colorectal adenomas. In women, neither gallbladder polyps nor gallbladder stones were significantly related to colon polyps.

CONCLUSIONS

Both gallbladder polyps and gallbladder stones were associated with an increased risk of colorectal adenomas in men but not in women. Gender difference was significant for the association between gallbladder lesions and colorectal polyps.

Frequency and risk factors of colorectal adenoma in patients with early gastric cancer

BACKGROUND/AIM

The authors aimed to determine the clinical value of colonoscopy by evaluating the frequency of colorectal neoplasm (CRN) detection in patients with early gastric cancer (EGC) as compared with healthy controls and analysed the risk factors of advanced CRN in patients with EGC.

METHODS

The medical records of 201 patients diagnosed as EGC and age- and gender-matched healthy controls were retrospectively reviewed. Frequencies and clinical features of colorectal polyps of patients and controls were compared. Risk factors of advanced CRN in patients with EGC were also analysed.

RESULTS

Frequencies of CRN in patients and controls were 49.8 and 49.3% respectively (P = 0.90). They were more common in the right colon in patients (P < 0.05). Advanced CRN were found in 10.3% of patients and in 3% of controls (P < 0.05). Multivariate analysis revealed that old age and smoking history were risk factors of an advanced CRN in patients with EGC.

CONCLUSION

The prevalence of a coexisting advanced CRN was higher in EGC patients. The study shows colonoscopy plays an important role with respect to the detection of synchronous advanced CRN in patients with EGC.

A simple scoring model for advanced colorectal neoplasm in asymptomatic subjects aged 40-49 years

Background

Limited data are available for advanced colorectal neoplasm in asymptomatic individuals aged 40–49 years. We aimed to identify risk factors and develop a simple prediction model for advanced colorectal neoplasm in these persons.

Methods

Clinical data were collected on 2781 asymptomatic subjects aged 40–49 years who underwent colonoscopy for routine health examination. Subjects were randomly allocated to a development or validation set. Logistic regression analysis was used to determine predictors of advanced colorectal neoplasm.

Results

The prevalence of overall and advanced colorectal neoplasm was 20.2 and 2.5% respectively. Older age (45–49 years), male sex, positive serology of Helicobacter pylori, and high triglyceride and low high-density lipoprotein (HDL) levels were independently associated with an increased risk of advanced colorectal neoplasm. BMI (body mass index) was not significant in multivariable analysis. We developed a simple scoring model for advanced colorectal neoplasm (range 0–9). A cutoff of ≥4 defined 43% of subjects as high risk for advanced colorectal neoplasm (sensitivity, 79%; specificity, 58%; area under the receiver operating curve = 0.72) in the validation datasets.

Conclusion

Older age (45–49 years), male sex, positive serology of H. pylori, high triglyceride level, and low HDL level were identified as independent risk factors for advanced colorectal neoplasm.

Early detection of high oxidative activity in patients with adenomatous intestinal polyps and colorectal adenocarcinoma: myeloperoxidase and oxidized low-density lipoprotein in serum as new markers of oxidative stress in colorectal cancer

OBJECTIVES

To detect whether signs of oxidative stress appear at early stages of colorectal adenocarcinoma (CRC), particularly in the polyp stage. We also aimed to evaluate the specific entities myeloperoxidase (MPO) and oxidized low-density lipoprotein (oxLDL) as novel markers of oxidation in the plasma of patients with CRC and to study the relationship between oxidative status in plasma and patient survival.

METHODS

We assayed serum or plasma specimens from healthy control subjects (n = 14), from patients with intestinal polyps (n = 39), and from patients with CRC (n = 128) to calculate the modified oxidative balance score (MOBS) using several serum markers (β-carotene, lycopene, vitamin A, vitamin E, MPO, and oxLDL). We also assayed the levels of C-reactive protein (CRP) and obtained lipid profiles. Finally, we studied the survival of patients in relationship to oxidative status (antioxidants and pro-oxidants) and inflammation markers, and added theses data to the lipid profile for each patient.

RESULTS

Oxidative stress levels increased as disease stage advanced. This increase was detected early in the polyp stage, before polyps progressed to cancer, and could be measured by the increase of such new markers as MPO and oxLDL, the decrease in antioxidants, and the MOBS value. Higher levels of oxidation correlated with lower survival.

CONCLUSION

The oxidation process, which can cause mutations leading to CRC, begins development in the polyp stage. This process may be detected early by monitoring serum markers such as MPO and oxLDL.

Blood Lipid Concentrations and Colorectal Adenomas: A Systematic Review and Meta-Analysis of Colonoscopy Studies in Asia, 2000-2014

It is unclear whether dyslipidemia is associated with risk of colorectal neoplasia. The incidence of both conditions is increasing in Asia, motivating a number of new studies from this region. We performed a systematic literature search of Asian colonoscopy-based studies that collected blood lipid concentrations at the time of endoscopy. Persons found to have colorectal adenoma were considered cases, and those found to be adenoma-free were considered controls. Seventeen studies published between 2000 and 2014 met inclusion criteria, collectively enrolling 17,387 cases and 30,427 controls. Mean differences and adjusted odds ratios were summarized with random-effects meta-analyses. Compared with controls, cases had higher total cholesterol (mean difference (MD) = 2.4 mg/dL, 95% confidence interval (CI): 0.2, 4.6), higher low-density lipoprotein cholesterol (MD = 1.3 mg/dL, 95% CI: 0.1, 2.6), higher triglyceride (MD = 16.4 mg/dL, 95% CI: 11.2, 21.5), and lower high-density lipoprotein (HDL) cholesterol (MD = -2.1 mg/dL, 95% CI: -2.7, -1.6) concentrations. Based on adjusted odds ratios, associations for 40-mg/dL-higher triglyceride levels (odds ratio = 1.13, 95% CI: 1.05, 1.21) and 10-mg/dL-higher HDL cholesterol levels (odds ratio = 0.96, 95% CI: 0.92, 1.00) achieved statistical significance. Persons with adenoma were more likely to have unfavorable cholesterol profiles at the time of colonoscopy than those without adenoma. The most convincing evidence for an association between dyslipidemia and colorectal neoplasia was observed for hypertriglyceridemia.

Ethnic disparities in the risk of colorectal adenomas associated with lipid levels: a retrospective multiethnic study

BACKGROUND

Although data exists showing that uncontrolled lipid levels in white and black patients is associated with colorectal adenomas, there are currently no studies looking only at the Hispanic population.

PURPOSE

With the rapid increase in the Hispanic population, we aimed to look at their risk of colorectal adenomas in association with lipid levels.

METHODS

We retrospectively analyzed 1473 patients undergoing colonoscopy from 2009 to 2011 at a community hospital. Statistical analysis was performed using Chi-squared for categorical variables and t test for continuous variables with age-, gender-, and race-adjusted odds ratios. Unconditional logistic regression model was used to estimate 95 % confidence intervals (CI). SAS 9.3 software was used to perform all statistical analysis.

RESULTS

In our general population, there was an association with elevated triglyceride levels greater than 150 and presence of multiple colorectal adenomas with odds ratio (OR) 1.60 (1.03, 2.48). There was an association with proximal colon adenomas and cholesterol levels between 200 and 239 with OR 1.57 (1.07, 2.30), and low-density lipoprotein (LDL) levels of greater than 130 with OR 1.54 (1.04, 2.30). There was no association between high-density lipoproteins (HDL) levels and colorectal adenomas. The Hispanic population showed no statistical correlation between elevated triglycerides, cholesterol, or LDL with the presence, size, location, or multiplicity of colorectal adenomas.

CONCLUSIONS

We found a significant correlation between elevated lipid levels and colorectal adenomas in white and black patients; however, there was no such association in the Hispanic population. This finding can possibly be due to environmental factors such as dietary, colonic flora, or genetic susceptibility, which fosters further investigation and research.

The association between serum lipids and colorectal neoplasm: a systemic review and meta-analysis

OBJECTIVE

There have been inconsistent results published regarding the relationship between dyslipidaemia and an increased risk of colorectal neoplasia (CRN), including colorectal adenoma (CRA) and colorectal cancer (CRC). We conducted a meta-analysis to explore the relationship between dyslipidaemia and CRN.

DESIGN

We identified studies by performing a literature search using PubMed, EMBASE and the Science Citation Index through October 2013.

SETTING

We analysed thirty-three independent studies reporting the association between CRN and at least one of the selected lipid components, including total cholesterol (TC), TAG, HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C).

SUBJECTS

CRN cases (n 21 809) were identified.

RESULTS

Overall, people with high levels of serum TAG (risk ratio (RR)=1.08; 95% CI 1.05, 1.12, P<0.00001) and LDL-C (RR=1.07; 95% CI 1.00, 1.14, P=0.04) presented an increased prevalence of CRN. Subgroup analyses revealed that high levels of serum TC (RR=1.04; 95% CI 1.01, 1.09, P=0.02), TAG (RR=1.06; 95% CI 1.03, 1.10, P=0.0009) and LDL-C (RR=1.11; 95% CI 1.04, 1.19, P=0.003) increased the risk of CRA but not of CRC. No association between serum HDL-C and risk for CRN (including CRA and CRC) was observed.

CONCLUSIONS

Both TAG and LDL-C were significantly associated with an increasing prevalence of CRN. High levels of serum TC, TAG and LDL-C were positively associated with CRA but not with CRC. No significant association was observed between levels of serum HDL-C and CRN.

The Valuable Role of Measuring Serum Lipid Profile in Cancer Progression

OBJECTIVE

Serum lipid levels are not only associated with etiology, but also with prognosis in cancer. To investigate this issue further, we aimed to evaluate the serum levels of lipids in association with the most important prognostic indicators in cancer patients at the start of chemotherapy.

METHODS

In a retrospective cross-sectional study, using existing medical records obtained from 2009-2014, the data of all incident cancer cases in Iranian patients referred to the Semnan oncology clinic for chemotherapy were analyzed. Data on demographics, cancer type, prognostic indicators (e.g. lymph node involvement, metastasis, and stage of disease), as well as the patient's lipid profile were collected. We used multiple logistic regression models to show the relationship between prognosis indicators and lipid profile adjusting for age, gender, and type of cancer.

RESULTS

The data of 205 patients was gathered. We found a significant difference in the lipid profile between different types of cancers (breast, colon, gastric, and ovarian). With the exception of high-density lipoprotein levels in women, which were higher than in men, the means of other lipid profiles were similar between the genders. There was a significant association between higher levels of low-density lipoprotein (LDL >110mg/dL) in the serum and metastasis (adjusted odds ratio=2.4, 95% CI 1.2-3.5). No significant association was reported between lipid profile and lymph nodes involvement and stage of the disease.

CONCLUSION

Our study suggested a benefit of measuring serum levels of lipids for predicting cancer progression. Increased LDL levels can be considered a predictive factor for increasing the risk of metastasis.

Associations between tumor markers and the risk of colorectal polyp recurrence in Chinese people

Colorectal cancer primarily arises from the polyps of the colon. Early identification of the recurrence of colorectal polyps represents the best opportunity to prevent the occurrence of colorectal cancer. Thus, the high risk of recurrence is the primary problem. The aim of this study was to examine the associations between tumor markers (CEA and CA19-9) and colorectal polyp recurrence in Chinese people. The risk of colorectal polyp recurrence was studied in 156 subjects (113 males and 43 females, 58.654±11.447 years old) who underwent colonoscopy and polypectomy for the first time between January 2011 and August 2014 at the First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China. All subjects underwent colonoscopies within 6-12 months. Between the colorectal polyp recurrence group and the no recurrence group, the CEA and CA19-9 levels were significantly different, and the trend analyses were consistent with increased risks of recurrence with increasing CEA and CA19-9 levels among the males and patients with single polyps, multiple polyps and proximal colon polyps. The recurrence of colorectal polyps was significantly associated with increased CEA and CA19-9 levels.

[Prevalence and risk factors of colorectal adenoma in 14,932 koreans undergoing screening colonoscopy]

BACKGROUND/AIMS

Current international guidelines recommend colorectal cancer screening for average-risk people over 50 years of age. Accordingly, we aimed to estimate the prevalence of colorectal neoplasms in all age groups and evaluate associated risk factors.

METHODS

Data of 14,932 subjects who underwent colonoscopy from July 2006 to January 2012 at Health Promotion Center, Gangnam Severance Hospital (Seoul, Korea) as part of a health check-up were reviewed retrospectively.

RESULTS

The overall prevalence of colorectal neoplasms and adenoma were 34.6% and 25.3%, respectively. Colorectal adenoma was found in 3.2%, 13.0%, 21.7%, 33.8%, 44.0%, 50.5%, and 54.2% of subjects under 30 years, 30-39 years, 40-49 years, 50-59 years, 60-69 years, 70-79 years, and over 80 years of age (trend p<0.0001). Independent predictors of colorectal adenoma included male gender (OR 2.38, 95% CI 2.084-2.718), positive occult blood (2.266, 1.761-2.917), positive serology of Helicobacter pylori (1.253, 1.114-1.409) and hypertriglyceremia (1.267, 1.065-1.508). Compared to the 30-39 years of age reference group, the ORs for each age group were 0.195 (under 30 years), 1.634 (40-49 years), 2.954 (50-59 years), 5.159 (60-69 years), 5.640 (70-79 years), 11.020 (over 80 years), while the 95% CIs were 0.071-0.536 (under 30 years), 1.340-1.992 (40-49 years), 2.421-3.604 (50-59 years), 4.109-6.476 (60-69 years), 3.822-8.322 (70-79 years), and 2.809-42.234 (over 80 years).

CONCLUSIONS

Colorectal adenoma prevalence increased proportionally with age. Only subjects under the age of 30 years had a definitely lower prevalence of colorectal adenoma. Male gender, positive occult blood, positive serology of H. pylori, and hypertriglyceremia were associated risk factors of colorectal adenoma.

Vegetarianism as a protective factor for colorectal adenoma and advanced adenoma in Asians

BACKGROUND

Although epidemiologic and animal studies suggest a vegetarian diet protects against the development of colorectal cancer, the relationship between vegetarian diet and incidence of colorectal adenoma is not yet conclusive, especially for Asians.

AIM

The purpose of this study was to examine the protective effect of a vegetarian diet against colorectal adenoma and advanced adenoma.

METHODS

This cross-sectional study compared the prevalence of colorectal adenoma among Buddhist priests, who are obligatory vegetarians, with that among age and sex-matched controls. All the subjects underwent health checkups in a health-promotion center in Korea.

RESULT

Colorectal adenoma and advanced adenoma were both more prevalent in the general population group than in the Buddhist priest group (25.2 vs. 17.9 %, 6.7 vs. 2.0 %). However, the prevalence of metabolic syndrome, high body mass index, and waist circumference were higher in the Buddhist priest group. According to univariate analysis, non-vegetarian diet (general population) significantly increased the prevalence of colorectal adenoma and advanced adenoma compared with a vegetarian diet (Buddhist priests) (OR 1.54, 95 % CI 1.08-2.21, P = 0.018; OR 3.60, 95 % CI 1.53-8.48, P = 0.003). In a conditional regression analysis model, non-vegetarian diet was also a significant risk factor for colorectal adenoma and advanced adenoma (OR 1.52, 95 % CI 0.75-2.07, P = 0.043; OR 2.94, CI 0.97-7.18, P = 0.036).

CONCLUSIONS

Vegetarianism may be effective in preventing both colorectal adenoma and advanced adenoma in Asians.

Canola oil influence on azoxymethane-induced colon carcinogenesis, hypertriglyceridemia and hyperglycemia in Kunming mice

Azoxymethane (AOM) is a potent genotoxic carcinogen which specifically induces colon cancer. Hyperlipidemia and diabetes have several influences on colon cancer development, with genetic and environmental exposure aspects. Here, we investigated plasma lipid and glucose concentrations in Kunming mice randomized into four groups; control (no AOM or oil exposure), AOM control, AOM + pork oil, and AOM + canola oil. Aberrant crypt foci (ACF), plasma cholesterol, plasma triglyceride, plasma glucose and organ weight were examined 32 weeks after AOM injection. Results revealed that AOM exposure significantly increased ACF number, plasma triglyceride and glucose level. Further, male mice displayed a much higher plasma triglyceride level than female mice in the AOM control group. Dietary fat significantly inhibited AOM-induced hypertriglyceridemia, and canola oil had stronger inhibitory effect than pork oil. AOM-induced hyperglycemia had no sex-difference and was not significantly modified by dietary fat. However, AOM itself not change plasma cholesterol level. AOM significantly increased liver and spleen weight in male mice, but decreased kidney weight in female mice. On the other hand, mice testis weight decreased when fed canola oil. AOM could induce colorectal carcinogenesis, hypertriglyceridemia and hyperglycemia in Kunming mice at the same time, with subsequent studies required to investigate their genome association.

Association between Obesity, Serum Lipids, and Colorectal Polyps in Old Chinese People

Background. Colorectal cancer mostly arises from the polyps of colon. The aim of our study was to examine the association of body mass index (BMI) and serum lipids with the colorectal polyps in old Chinese people. Methods. The risk of developing colorectal polyps was studied in 244 subjects (212 men and 32 women, 74.63 ± 11.63 years old) who underwent colonoscopy for the first time from January 2008 to July 2012 at the Navy General Hospital, Beijing, China. According to the results of colonoscopy, all the subjects were divided into 112 normal control, 38 right colorectal polyps, 53 left colorectal polyps, and 41 both right and left colorectal polyps groups. The total plasma cholesterol, plasma triglyceride, plasma creatinine concentration, blood urinary nitrogen, and fasting glucose were determined using a multichannel analyzer. Results. There were significant differences among normal control, right colorectal polyps, left colorectal polyps, and both right and left polyps groups, which were the BMI, total cholesterol, triglycerides, creatinine, and urinary nitrogen. In binary logistic regression analysis, there were two risk factors associated with the occurrence of colorectal polyps, which included BMI and systolic blood pressure. Conclusions. Colorectal polyps were significantly associated with increased BMI, total cholesterol, and triglycerides levels.

Association between Plasma Levels of Plasminogen Activator Inhibitor-1 and Colorectal Neoplasms

Background/Aims

Plasminogen activator inhibitor-1 (PAI-1) is important for tumor growth, Invasion, and metastasis. In this study, we investigated the relationship between plasma levels of PAI-1 and colorectal adenomas.

Methods

We reviewed the medical records of 3,136 subjects who underwent colonoscopy as a screening exam. The subjects were classified into a case group with adenomas (n=990) and a control group (n=2,146). Plasma PAI-1 levels were categorized into three groups based on tertile.

Results

The plasma levels of PAI-1 were significantly higher in adenoma cases than in controls (p=0.023). The prevalence of colorectal adenomas increased significantly with increasing levels of PAI-1 (p=0.038). In the adenoma group, advanced pathologic features, size, and number of adenomas did not differ among the three groups based on tertiles for plasma PAI-1 levels. Using multivariate analysis, we found that plasma level of PAI-1 was not associated with the risk of colorectal adenomas (p=0.675). Adjusted odds ratios for colorectal adenomas according to increasing plasma levels of PAI-1 were 0.980 (95% confidence interval [CI], 0.768 to 1.251) for the second-highest plasma level and 1.091 (95% CI, 0.898 to 1.326) for the highest level, compared with the lowest levels.

Conclusions

These results suggest that elevated plasma PAI-1 levels are not associated with the risk of colorectal neoplasms.

The association of serum lipids with colorectal adenomas

OBJECTIVES

There is suggestive but sparse evidence that dyslipidemia is associated with colorectal neoplasms. We investigated the association of serum lipid and apolipoprotein concentrations with the prevalence of colorectal adenomas.

METHODS

Cross-sectional study of 19,281 consecutive participants aged 40-79 years undergoing screening colonoscopy at the Center for Health Promotion of the Samsung Medical Center in Korea from January 2006 to June 2009.

RESULTS

We identified 5,958 participants with colorectal adenomas (30.9%), including 5,504 (28.5%) with non-advanced adenomas and 454 (2.4%) with advanced adenomas. The adjusted relative prevalence ratios (aRPRs) comparing the fourth with the first quartiles of serum triglycerides were 1.35 (95% confidence interval (CI) 1.20-1.52; P trend<0.001) for non-advanced adenomas and 1.45 (95% CI 1.02-2.06; P trend=0.005) for advanced adenomas. Higher levels of high-density lipoprotein (HDL) cholesterol and apolipoprotein A-1 (ApoA-1) were significantly associated with 12% (Q4 vs. Q1 aRPR 1.12; 95% CI 1.00-1.26; P trend=0.049) and 17% (Q4 vs. Q1 aRPR 1.17; 95% CI 1.04-1.31; P trend=0.004) higher prevalence of non-advanced adenoma. There was also a non-significant association between higher levels of low-density lipoprotein (LDL) cholesterol (Q4 vs. Q1 aRPR 1.22; 95% CI 0.91-1.66; P trend= 0.12) and apolipoprotein B (ApoB) (Q4 vs. Q1 aRPR 1.32; 95% CI 0.94-1.83; P trend=0.07) with higher prevalence of advanced adenoma. There was no association between total cholesterol levels with colorectal adenoma.

CONCLUSIONS

In this large cross-sectional study, higher levels of serum triglycerides were significantly associated with an increasing prevalence of both non-advanced and advanced colorectal adenomas, while higher levels of ApoA-1 and HDL cholesterol were significantly associated with an increasing prevalence of non-advanced adenomas.

Role of preoperative colonoscopy in patients with gastric cancer: a case control study of the prevalence of coexisting colorectal neoplasms

BACKGROUND

We evaluated the prevalence of coexisting asymptomatic colorectal neoplasm (CRN) in patients with gastric cancer (GC).

METHODS

Preoperative colonoscopic examinations were performed in 495 patients with GC who underwent gastrectomy between January 2009 and December 2010. To compare the prevalence of CRN in these patients with that in a normal population, we selected 495 sex- and age-matched persons who underwent colonoscopies for health screening. Risk factors for CRN were evaluated by univariate and multivariate analyses.

RESULTS

The overall incidence of CRN was 41.8 % (414/990). The prevalence of overall CRN, high-risk CRN, and colorectal carcinoma (CRC) were significantly higher in the GC group than in the control group (overall CRN: 48.9 % vs. 34.7 %; high-risk CRN: 28.3 % vs. 13.5 %; CRC: 2.6 % vs. 0.2 %; all P < 0.001). The presence of GC [odds ratio (OR), 1.82; 95 % confidence interval (CI), 1.4-2.38; P < 0.001], age ≥50 years (OR, 2.58; 95 % CI, 1.75-3.81; P < 0.001), and male sex (OR, 2.28; 95 % CI, 1.72-3.02; P < 0.001) were risk factors for overall CRN. In patients with GC, age ≥40 years (OR, 3.22; 95 % CI, 1.24-8.37; P = 0.016) and male sex (OR, 3.21; 95 % CI, 2.17-4.76; P < 0.001) were risk factors for overall CRN.

CONCLUSIONS

The prevalence of coexisting CRN, including CRC, was higher in patients with GC than in the normal population. Preoperative colonoscopy is strongly indicated in patients with GC who are male and/or ≥40 years of age.

Serum Lipids and the Risk of Gastrointestinal Malignancies in the Swedish AMORIS Study

Background. Metabolic syndrome has been linked to an increased cancer risk, but the role of dyslipidaemia in gastrointestinal malignancies is unclear. We aimed to assess the risk of oesophageal, stomach, colon, and rectal cancers using serum levels of lipid components. Methods. From the Swedish Apolipoprotein Mortality Risk (AMORIS) study, we selected 540,309 participants (> 20 years old) with baseline measurements of total cholesterol (TC), triglycerides (TG), and glucose of whom 84,774 had baseline LDL cholesterol (LDL), HDL cholesterol (HDL), apolipoprotein B (apoB), and apolipoprotein A-I (apoA-I). Multivariate Cox proportional hazards regression was used to assess glucose and lipid components in relation to oesophageal, stomach, colon, and rectal cancer risk. Results. An increased risk of oesophageal cancer was observed in persons with high TG (e.g. HR: 2.29 (95% CI: 1.42–3.68) for the 4th quartile compared to the 1st) and low LDL, LDL/HDL ratio, TC/HDL ratio, log (TG/HDL), and apoB/apoA-I ratio. High glucose and TG were linked with an increased colon cancer risk, while high TC levels were associated with an increased rectal cancer risk. Conclusion. The persistent link between TC and rectal cancer risk as well as between TG and oesophageal and colon cancer risk in normoglycaemic individuals may imply their substantiality in gastrointestinal carcinogenesis.

Preclinical cancer chemoprevention studies using animal model of inflammation-associated colorectal carcinogenesis

Inflammation is involved in all stages of carcinogenesis. Inflammatory bowel disease, such as ulcerative colitis and Crohn’s disease is a longstanding inflammatory disease of intestine with increased risk for colorectal cancer (CRC). Several molecular events involved in chronic inflammatory process are reported to contribute to multi-step carcinogenesis of CRC in the inflamed colon. They include over-production of free radicals, reactive oxygen and nitrogen species, up-regulation of inflammatory enzymes in arachidonic acid biosynthesis pathway, up-regulation of certain cytokines, and intestinal immune system dysfunction. In this article, firstly I briefly introduce our experimental animal models where colorectal neoplasms rapidly develop in the inflamed colorectum. Secondary, data on preclinical cancer chemoprevention studies of inflammation-associated colon carcinogenesis by morin, bezafibrate, and valproic acid, using this novel inflammation-related colorectal carcinogenesis model is described.

The relationship between nonalcoholic fatty liver disease and colorectal cancer: the future challenges and outcomes of the metabolic syndrome

Nonalcoholic fatty liver disease (NAFLD) is closely related to insulin resistance, metabolic syndrome, obesity, type 2 diabetes, and dyslipidaemia. Obesity and metabolic syndrome are associated with an increased cancer risk, and recent evidence demonstrated an association between NAFLD and colorectal cancer (CRC). The mechanism of how NAFLD can be associated with increased risk of CRC is not fully understood; however, NAFLD represents a condition of profound insulin resistance and a proinflammatory state. Insulin and insulin-like growth factors may promote the development of CRC through their proliferative and antiapoptotic effects. Patients with NAFLD have reduced expression of adiponectin, an adipokine with anti-inflammatory effects. Importantly, hypoadiponectinemia is associated with an increased risk of CRC. Decreased levels of adiponectin lead to increased insulin levels due to marked insulin resistance and in turn increased insulin growth factor-1 (IGF-1). Insulin binds to IGF-1 receptors and plays an important role in cell proliferation, apoptosis, and increased production of vascular endothelial growth factor, an angiogenic factor that supports cancer growth. Further studies are needed to establish (i) the pathophysiology of NAFLD with colorectal cancer, (ii) the benefit of early screening of CRC in NAFLD patients, and (iii) the impact of treatment of NAFLD in the modulation of the risk of colorectal cancer.

Metabolic syndrome, lifestyle risk factors, and distal colon adenoma: A retrospective cohort study

AIM: To investigate relationships between colorectal adenoma incidence, metabolic syndrome (MS) components and lifestyle factors.

METHODS: We conducted a retrospective cohort study using data from individuals who had multiple sigmoidoscopies for colon cancer at the Health Promotion Center of Ulsan University Hospital in Korea from 1998 to 2007.

RESULTS: By multivariate analysis, the incidence of distal colon adenoma was increased by more than 1.76 times in individuals with at least one component of MS compared to those without a component of MS. After adjustment for age, gender, smoking, drinking, and physical exercise, only high body mass index (BMI) was significantly associated with the incidence of distal colon adenoma (Hazard ratio 1.66, 95% confidence interval 1.05-2.62).

CONCLUSION: Our results suggest that high BMI may increase the risk of colorectal adenoma in Korean adults.

The association of serum lipids with the histological pattern of rectosigmoid adenoma in Taiwanese adults

BACKGROUND

The mortality rate of colorectal cancer ranks third behind lung and hepatic cancer in Taiwan. Colorectal cancer mostly arises from adenomatous polyps of left colon. The aim of our study was to examine the association of serum lipids with the histological pattern of rectosigmoid adenoma.

METHODS

There were 2,506 eligible examinees aged 20 and above who underwent sigmoidoscopy as a screening examination in National Cheng Kung University Hospital between January 2003 and October 2006. They were classified into three groups: tubular adenoma (333 subjects), villous-rich (tubulovillous/villous) adenoma (53 subjects) and normal (2,120 subjects). We defined high total cholesterol (TC) as a level ≧200 mg/dl, low high-density lipoprotein cholesterol (HDL-C) as a level <40 mg/dL, and high triglyceride (TG) as a level ≧200 mg/dl according to the third report of the National Cholesterol Education Program expert panel on detection, evaluation, and treatment of high blood cholesterol in adults. Adenoma histology was classified as tubular, tubulovillous and villous according to the proportion of villous part.

RESULTS

Among the study population, 333 subjects (13.3%) had tubular adenomas and 53 subjects (2.1%) had villous-rich adenomas. The odds ratio (OR) for villous-rich adenoma in subjects with TG≧200 mg/dL compared to those with TG < 200 mg/dL was 3.20 (95% confidence interval [CI]:1.71-6.01), after adjusting for age, gender, general obesity, central obesity, diabetes, hypertension, smoking, and alcohol consumption. If further taking high TC and low HDL-C into consideration, the OR was 4.42 (95% CI:2.03-9.63).

CONCLUSIONS

Our study showed that subjects with high serum TG tended to have a higher risk of tubulovillous/villous adenoma in rectosigmoid colon. Therefore, reducing the serum TG level might be one method to prevent the incidence of colorectal cancer.

Metformin reduces the stimulatory effect of obesity on in vivo Walker-256 tumor development and increases the area of tumor necrosis

AIMS

The objective of this study was to analyze the influence of obesity and insulin resistance on tumor development and, in turn, the effect of insulin sensitizing agents.

MAIN METHODS

Male offspring of Wistar rats received monosodium glutamate (400mg/kg) (obese) or saline (control) from the second to sixth day after birth. Sixteen-week-old control and obese rats received 5×10(5) Walker-256 tumor cells, subcutaneously injected into the right flank. Some of the obese and control rats received concomitant treatment with metformin (300mg/kg) by gavage. At the 18th week, obesity was characterized. The percentage of rats that developed tumors, the tumor relative weight and the percentage of cachexia incidence were analyzed. The tumor tissue was evaluated histologically by means of hematoxylin and eosin staining.

KEY FINDINGS

Metformin did not correct the insulin resistance in obese rats. The tumor development was significantly higher in the obese group, whereas metformin treatment reduced it. After pathological analysis, we observed that the tumor tissues were similar in all groups except for adipocytes, which were found in greater quantity in the obese and metformin-treated obese groups. The area of tumor necrosis was higher in the group treated with metformin when compared with the untreated one.

SIGNIFICANCE

Metformin reduced Walker-256 tumor development but not cachexia in obese rats. The reduction occurred independently of the correction of insulin resistance. Metformin increased the area of necrosis in tumor tissues, which may have contributed to the reduced tumor development.

Association of lipid metabolism with ovarian cancer

Defects in lipid metabolism have been found to be linked to several diseases, among which atherosclerosis, hypertension, obesity, and diabetes are the most important. Although cancer is chiefly a genetic disease, dietary lipid intake and metabolism are related to some cancer risks, including the risk for ovarian cancer. Higher intake of dietary lipids, systemic lipid metabolism malfunction, and abnormal serum lipid levels are somehow related to ovarian cancer. Overexpression of some lipid metabolic enzymes are also found in ovarian cancer. In this review article, we summarize the relationships between lipid intake, lipid metabolism, and ovarian cancer.

Decreased levels of plasma adiponectin associated with increased risk of colorectal cancer

AIM: To investigate the association between adiponectin levels and risk of colorectal adenoma and cancer (early and advanced).

METHODS: A cross-sectional study in a cohort of hospital-based patients was conducted between January 2004 and March 2006 at Yamagata University Hospital. Male subjects, who had colorectal tumors detected by endoscopic examination, were enrolled according to inclusion and exclusion criteria. Based on the T factor of the TNM system, intraepithelial carcinoma and submucosally invasive carcinoma were defined as early cancer, and invasion into the muscularis propria or deeper was defined as advanced cancer. The plasma levels of glucose, insulin, total cholesterol, triglyceride, high sensitivity C-reactive protein, insulin like growth factor (IGF)-1, IGF binding protein-3, adiponectin, leptin, and resistin were measured. Each factor level was designated low or high, and the risk of adenoma or cancer was estimated by univariate and multivariate logistic regression analysis.

RESULTS: We enrolled 124 male subjects (47 with adenoma, 34 with early cancer, 17 with advanced cancer, and 26 without tumors as controls). In patients with adenoma, high triglyceride and low adiponectin were associated with a significant increase in the odds ratio (OR) by univariate analysis. Only a low adiponectin level was related to increased adenoma risk, with an adjusted OR for low level (< 11 μg/mL) to high (≥11 μg/mL) of 5.762 (95% confidence interval (CI): 1.683-19.739, P = 0.005). In the patients with early cancer, high body mass index, high triglyceride, and low adiponectin were associated with a significant increase in OR in univariate analysis. In multivariate analysis, only low adiponectin was significantly associated with early cancer, with an adjusted OR of 4.495 (95% CI: 1.090-18.528, P = 0.038). However, in patients with advanced cancer, low adiponectin was not recognized as a significant risk factor for advanced cancer.

CONCLUSION: A decreased level of adiponectin is strongly associated with an increased risk of colorectal adenoma and early cancer. These data call for further investigation, including a controlled prospective study.

Visceral obesity and insulin resistance as risk factors for colorectal adenoma: a cross-sectional, case-control study

OBJECTIVES

Colorectal adenoma is known to be associated with obesity, but the association between colorectal adenoma and visceral adipose tissue (VAT) area measured by abdominal computed tomography (CT) has not been documented clearly. In addition, the relationship between insulin resistance and colorectal adenomas, which underlies the mechanism that links obesity and colorectal adenoma, has not been studied extensively. The aim of this study was to examine VAT area and insulin resistance as risk factors of colorectal adenoma.

METHODS

A cross-sectional, case-control study was conducted in Koreans that presented for health check-ups. Subjects underwent various laboratory tests, abdominal CT, and colonoscopy. VAT, subcutaneous adipose tissue (SAT), and homeostatic metabolic assessment (HOMA) index were evaluated as potential risk factors of colorectal adenoma in 2,244 age- and sex-matched subjects.

RESULTS

According to univariate analysis, the prevalences of smoking, hypertension, metabolic syndrome, and family history of colorectal cancer were higher in the adenoma group than in the normal control group. In addition, body mass index, waist circumference, triglyceride, high-density lipoprotein cholesterol, and VAT and SAT areas were significantly different in the two groups. According to the multivariate analysis adjusted for multiple confounders, VAT area was independently associated with the risk of colorectal adenoma (odds ratio (OR)=3.09, 95% confidence interval (CI): 2.19-4.36, highest quintile vs. lowest quintile). Mean HOMA index was higher in the adenoma group than in the control group (OR=1.99, 95% CI: 1.35-2.92, highest vs. lowest quintile).

CONCLUSIONS

Visceral obesity was found to be an independent risk factor of colorectal adenoma, and insulin resistance was associated with the presence of colorectal adenoma.

Serum triglyceride concentrations and cancer risk in a large cohort study in Austria

Background:

Blood lipid levels as part of the metabolic syndrome are thought to be linked to cancer risk. Few epidemiological studies have addressed the association between serum triglyceride (STG) concentrations and cancer risk.

Methods:

Serum triglyceride concentrations were collected in a health investigation (1988–2003). The analyses included 156 153 subjects (71 693 men and 84 460 women), with 5079 incident cancers in men and 4738 cancers in women, and an average of 10.6 years of follow-up. All malignancies were ascertained from the population cancer registry. Multivariate Cox proportional hazard models stratified by age and sex were used to determine adjusted cancer risk estimates and 95% confidence interval (95% CI).

Results:

In men and women combined, higher STG concentrations were associated with increased risk of lung (4th vs 1st quartile: HR, 1.94; 95% CI, 1.47–2.54), rectal (HR, 1.56; 95% CI, 1.00–2.44), and thyroid cancer (HR, 1.96; 95% CI, 1.00–3.84). Serum triglyceride concentrations were inversely associated with non-Hodgkin's lymphoma. In men, STG concentrations were inversely associated with prostate cancer and positively with renal cancer. In women, STG concentrations were positively associated with gynaecological cancers. Stratification by BMI revealed a higher risk of gynaecological cancers in overweight than in normal weight women. No other associations were found.

Conclusions:

Our findings support the hypothesis that STG concentrations are involved in the pathogenesis of lung, rectal, thyroid, prostate, and gynaecological cancers.

Physical activity as a determinant of fecal bile acid levels

Physical activity is protective against colon cancer, whereas colonic bile acid exposure is a suspected risk factor. Although likely related, the association between physical activity and bile acid levels has not been well-studied. Furthermore, the effect of triglycerides, which are known to modify bile acid levels, on this relationship has not been investigated. We conducted a cross-sectional analysis of baseline fecal bile acid levels for 735 colorectal adenoma formers obtained from participants in a phase III ursodeoxycholic acid chemoprevention trial. Compared with the lowest quartile of recreational physical activity duration, the highest quartile was associated with a 17% lower fecal bile acid concentration, adjusted for age, sex, dietary fiber intake, and body mass index (P = 0.042). Furthermore, consistent with a previously established relationship between serum triglyceride levels and bile acid metabolism, we stratified by triglyceride level and observed a 34% lower fecal bile acid concentration (highest versus lowest quartiles of physical activity) in individuals with low triglycerides (<136 mg/dL; P = 0.002). In contrast, no association between physical activity and fecal bile acid concentration was observed for subjects with high triglycerides (> or =136 mg/dL). Our results suggest that the biological mechanism responsible for the protective effect of physical activity on the incidence of colon cancer may be partially mediated by decreasing colonic bile acid exposure. However, this effect may be limited to individuals with lower triglyceride levels.

Modifiable risk factors for colorectal neoplasms and hyperplastic polyps

PURPOSE

Obesity, smoking and alcohol are modifiable putative risk factors for colorectal neoplasms (CRN) and hyperplastic polyps (HP). The aim of this study was to evaluate the strength of association between these modifiable risk factors and colorectal polyps.

METHODS

These risk factors were assessed by using a questionnaire completed by the patient prior to colonoscopy. Eight hundred-seventy consecutive patients satisfying inclusion criteria who had undergone a complete colonoscopy were divided into 4 groups: CRN (n=194), HP (n=132), CRN and HP (n=42) and control (neither CRN nor HP; n=586). Multiple logistic regression was performed.

RESULTS

The ORs [95%CI] of both CRN and HP for incremental body mass index expressed in 2 categories (>or=22, >or=25) were 2.12 [1.00, 4.50] and 1.41 [0.53, 3.77], respectively. The ORs [95%CI] of CRN and HP for heavy smoking of over 20 pack-years were 1.66 [1.05, 2.64] and 1.67 [1.01, 2.77], respectively. The ORs of CRN and HP for habitual alcohol drinking (median ethanol intake 32 g/day and interquartile range 18-40 g/day) were 1.31 [0.86, 1.98] and 1.91 [1.06, 3.47], respectively. CRN and HP were correlated with each other (p=0.0043, chi-square test). Aging was a significant risk factor for all three groups of colorectal polyps.

CONCLUSION

These findings are especially important since smoking and alcohol consumption are modifiable risk factors. Heavy smokers should be encouraged to quit to reduce their risk of CRN and HP. Habitual drinkers should be warned of the risk of HP. HP can be a marker of coincidence of CRN.

Does the lipid-lowering peroxisome proliferator-activated receptors ligand bezafibrate prevent colon cancer in patients with coronary artery disease?

BACKGROUND

Epidemiologic studies have suggested that hypertriglyceridemia and insulin resistance are related to the development of colon cancer. Nuclear peroxisome proliferator-activated receptors (PPAR), which play a central role in lipid and glucose metabolism, had been hypothesized as being involved in colon cancerogenesis. In animal studies the lipid-lowering PPAR ligand bezafibrate suppressed colonic tumors. However, the effect of bezafibrate on colon cancer development in humans is unknown. Therefore, we proposed to investigate a possible preventive effect of bezafibrate on the development of colon cancer in patients with coronary artery disease during a 6-year follow-up.

METHODS

Our population included 3011 patients without any cancer diagnosis who were enrolled in the randomized, double blind Bezafibrate Infarction Prevention (BIP) Study. The patients received either 400 mg of bezafibrate retard (1506 patients) or placebo (1505 patients) once a day. Cancer incidence data were obtained by matching a subject's identification numbers with the National Cancer Registry. Each matched record was checked for correct identification.

RESULTS

Development of new cancer (all types) was recorded in 177 patients: in 79 (5.25%) patients from the bezafibrate group vs. 98 (6.51%) from the placebo group. Development of colon cancer was recorded in 25 patients: in 8 (0.53%) patients from the bezafibrate group vs. 17 (1.13%) from the placebo group, (Fisher's exact test: one side p = 0.05; two side p = 0.07). A difference in the incidence of cancer was only detectable after a 4 year lag and progressively increased with continued follow-up. On multivariable analysis the colon cancer risk in patients who received bezafibrate tended to be lower with a hazard ratio of 0.47 and 95% confidence interval 0.2-1.1.

CONCLUSION

Our data, derived from patients with coronary artery disease, support the hypothesis regarding a possible preventive effect of bezafibrate on the development of colon cancer.

Obesity-related promotion of aberrant crypt foci in DMH-treated obese Zucker rats correlates with dyslipidemia rather than hyperinsulinemia

BACKGROUND

Obesity and energy restriction modulate the development of precancerous aberrant crypt foci (ACF) in animal models of colon cancer.

AIM

Investigation of the major obesity-associated determinants for ACF-development and underlying mechanisms leading to ACF-modulation, such as changes in DNA damage or colonocytes hyperproliferation.

METHODS

Lean and obese Zucker rats fed ad libitum (a.l.) or obese pair fed (p.f.) were induced with 1,2-dimethylhydrazine (DMH) for colon cancer. Multiple regression analyses were performed to identify major metabolic factors correlated with ACF number and size (aberrant crypts/ACF). DNA damage is analyzed by the comet-assay, epithelial proliferation by immunohistochemistry.

RESULTS

Aberrant crypt foci number was significantly elevated in Zucker obese a.l. (205.7+/-65.4 vs. lean 9.5+/-6.3, P<0.05) and is reduced by pair feeding in Zucker obese rats (81.4+/-28.5 vs. obese a.l., P<0.05). Compared to lean the ACF size was higher in Zucker obese a.l. (2.1+/-0.3 vs. lean 1.3+/-0.2., P<0.05) but is not reduced by pair feeding (1.7+/-0.2; P>0.05). While ACF number and size were modulated by genotype and/or pair feeding the DMH-induced DNA damage and hyperproliferation in colonocytes did not differ significantly between groups. Regression analysis showed that plasma parameters associated with lipid-metabolism (triglycerides, cholesterol, malondialdehyde) significantly correlated with the ACF number and size while parameters linked to carbohydrate-metabolism (glucose, insulin) were weaker determinants.

CONCLUSION

Obesity or pair feeding-associated modulation of ACF correlate with parameters related to lipid-metabolism but is not accompanied by changes in DNA damage and proliferation.

Hyperglycaemia, hypercholesterolaemia and the risk for developing gastric dysplasia

BACKGROUND/GOALS

Gastric dysplasia is believed to be the penultimate stage of gastric carcinogenesis. Few studies have evaluated whether there is a relationship between such risk factors and gastric dysplasia. This case-control study was conducted to investigate the associations between obesity, serum glucose, lipids and gastric dysplasia.

STUDY

Endoscopic findings and pathology specimens were reviewed from 1 July 1997 to 31 December 2006 in the Health Promotion Center. One hundred thirty patients have the dysplasia in the stomach during screening endoscopy. The same number of controls was evaluated and matched to the gastric dysplasia group for age and gender.

RESULT

The univariate analysis showed that the dysplasia risk was slightly increased among persons with a higher low-density lipoprotein, lower high-density lipoprotein, impaired fasting glucose and higher total cholesterol. However, a higher body mass index and higher triglyceride level were not associated with the diagnosis of gastric dysplasia. In the multivariate-adjusted model, a higher low-density lipoprotein cholesterol and glucose were strongly associated with an increased risk of dysplasia compared to the controls. However, the body mass index, triglyceride and total cholesterol were not associated with the risk for dysplasia.

CONCLUSION

Hyperglycaemia and low-density lipoprotein cholesterol appear to be associated with the risk for gastric dysplasia. Further epidemiologic studies including a large cohort of patients with gastric dysplasia and adenocarcinoma are needed to clarify the association of low-density lipoprotein cholesterol, serum glucose and gastric carcinogenesis.

Serum lipid levels and the risk of biliary tract cancers and biliary stones: A population-based study in China

Biliary tract cancers, encompassing the gallbladder, extrahepatic bile ducts and ampulla of Vater, are rare but highly fatal malignancies. Gallstones, the predominant risk factor for biliary cancers, are linked with hyperlipidemia. As part of a population-based case-control study conducted in Shanghai, China, we examined the associations of serum lipid levels with biliary stones and cancers. We included 460 biliary cancer cases (264 gallbladder, 141 extrahepatic bile duct, and 55 ampulla of Vater), 981 biliary stone cases and 858 healthy individuals randomly selected from the population. Participants completed an in-person interview and gave overnight fasting blood samples. Participants in the highest quintile of triglycerides (>/=160 mg/dl) had a 1.4-fold risk of biliary stones (95% CI = 1.1-1.9), a 1.9-fold risk of gallbladder cancer (95% CI = 1.3-2.8), and a 4.8-fold risk of bile duct cancer (95% CI = 2.8-8.1), compared to the reference group (third quintile: 90-124 mg/dl). Participants in the lowest quintile of high-density lipoprotein (HDL) (<30 mg/dl) had a 4.2-fold risk of biliary stones (95% CI = 3.0-6.0), an 11.6-fold risk of gallbladder cancer (95% CI = 7.3-18.5), and a 16.8-fold risk of bile duct cancer (95% CI = 9.1-30.9), relative to the reference group (third quintile: 40-49 mg/dl). In addition, total cholesterol, low-density lipoprotein (LDL) and apolipoprotein A (apo A) were inversely associated with biliary stones; whereas low levels as well as high levels of total cholesterol, LDL, apo A and apolipoprotein B (apo B) were associated with excess risks of biliary tract cancers. Our findings support a role for serum lipids in gallstone development and biliary carcinogenesis.

Reduced susceptibility of muscle-specific insulin receptor knockout mice to colon carcinogenesis

Insulin resistance is a risk factor for colon cancer, but it is not clear which of its metabolic sequelae are involved. The objective of this study was to determine whether increased adiposity and elevated circulating lipids commonly seen in insulin resistance promote colon carcinogenesis independent of changes in insulin. We made use of muscle-specific insulin receptor knockout (MIRKO) mice that exhibit elevated serum triglycerides (TG), free fatty acids (FFA), and fat mass but have similar body weights, circulating glucose, and insulin and insulin sensitivity to their wild-type littermates used as controls. Seven-week-old male MIRKO mice and controls received four weekly intraperitoneal injections of either 5 mg/kg azoxymethane (AOM) to induce aberrant crypt foci (ACF) or 10 mg/kg AOM to induce tumors and were killed at 24 or 40 wk of age, respectively. The MIRKO mice displayed hyperinsulinemia at 7 wk of age and reduced insulin sensitivity at 16 wk of age compared with controls. The previously reported MIRKO phenotype developed between 16 and 24 wk of age. By 40 wk of age, however, MIRKO mice were again insulin resistant. ACF development did not differ between MIRKO mice and controls, but MIRKO mice developed significantly fewer colon tumors. Our results suggest that circulating TG and FFA are not promoters of colon tumor development. Indeed, we show that the cumulative effects of the metabolic changes that occur with knockout of the insulin receptor in muscle are associated with reduced susceptibility to colon tumorigenesis.

A lipophilic statin, pitavastatin, suppresses inflammation-associated mouse colon carcinogenesis

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are known to modulate carcinogenesis. In this study, we investigated whether a lipophilic HMG-CoA reductase inhibitor pitavastatin suppresses inflammation-related mouse colon carcinogenesis. Male CD-1 (ICR) mice were initiated with a single intraperitoneal injection of azoxymethane (AOM, 10 mg/kg body weight) and promoted by 2% (w/v) dextran sodium sulfate (DSS) in drinking water for 7 days. The experimental diets containing pitavastatin at 2 dose levels (1 and 10 ppm) were fed to male CD-1 (ICR) mice for 17 weeks, staring 1 week after the cessation of DSS exposure. The effects of dietary pitavastatin on colonic tumor development were assessed at Weeks 5, 10 and 20. Feeding with pitavastatin at both doses significantly inhibited the multiplicity of colonic adenocarcinoma at Week 20. Furthermore, the treatment significantly lowered the positive rates of proliferating cell nuclear antigen and increased the apoptotic index in the colonic epithelial malignancies. The treatment also reduced nitrotyrosine-positivity in the colonic mucosa. Our findings thus show that pitavastatin is effective in inhibiting colitis-related colon carcinogenesis through modulation of mucosal inflammation, oxidative/nitrosative stress, and cell proliferation.

Metabolic syndrome, hyperinsulinemia, and colon cancer: a review

An impressive body of epidemiologic data collected over the past decade indicates that the risk of colon cancer is elevated in those with metabolic syndrome. This evidence includes studies that examined the risk of colon cancer or adenoma in relation to determinants of the metabolic syndrome (obesity, abdominal distribution of adiposity, and physical inactivity), clinical consequences of this syndrome (type 2 diabetes and hypertension), plasma or serum components of the definition of metabolic syndrome (hypertriglyceridemia, hyperglycemia, and low HDL cholesterol), and markers of hyperinsulinemia or insulin resistance (insulin and C-peptide), which is the underlying metabolic defect of the metabolic syndrome. The mechanism underlying these associations is unknown but may involve the influence of hyperinsulinemia in enhancing free or bioavailable concentrations of insulin-like growth factor-1. Future studies should also be based on better measurements of insulin resistance, beta-cell depletion, and insulin responses to better assess which aspects of insulin resistance are most closely related to the risk of colon neoplasia.

The role of obesity and related metabolic disturbances in cancers of the colon, prostate, and pancreas

Recent evidence indicates that obesity and related metabolic abnormalities are associated with increased incidence or mortality for a number of cancers, including those of the colon, prostate, and pancreas. Obesity, physical inactivity, visceral adiposity, hyperglycemia, and hyperinsulinemia are relatively consistent risk factors for colon cancer and adenoma. Also, patients with type 2 diabetes mellitus have a higher risk of colon cancer. For prostate cancer, the relationship to obesity appears more complex. Obesity seems to contribute to a greater risk of aggressive or fatal prostate cancer but perhaps to a lower risk of nonaggressive prostate cancer. Furthermore, men with type 2 diabetes mellitus are at lower risk of developing prostate cancer. Long-standing type 2 diabetes increases the risk of pancreatic cancer by approximately 50%. Furthermore, over the past 6 years, a large number of cohort studies have reported positive associations between obesity and pancreatic cancer. Together with data from prediagnostic blood specimens showing positive associations between glucose levels and pancreatic cancer up to 25 years later, sufficient evidence now supports a strong role for diabetes and obesity in pancreatic cancer etiology. The mechanisms for these associations, however, remain speculative and deserve further study. Hyperinsulinemia may be important, but the role of oxidative stress initiated by hyperglycemia also deserves further attention.

Serum triglycerides and colorectal adenoma in a case-control study among cancer screening examinees (Japan)

OBJECTIVE

Most epidemiologic studies have shown serum triglycerides to be associated with colorectal adenoma. However, whether the association can be modified by smoking is unknown. We cross-sectionally investigated the association of serum triglycerides with the risk of adenoma by smoking status.

METHODS

We identified 782 newly diagnosed adenoma cases from the examinees of a colorectal cancer screening program. All cases were diagnosed by a magnifying colonoscopy with dye spreading. We determined 738 controls without present illness or past history of adenoma from among the examinees. They provided their lifestyle information and fasting blood samples to measure their serum triglycerides. We calculated odds ratios (OR) and 95% confidence intervals (CI) of colorectal adenoma for serum triglycerides.

RESULTS

High serum triglycerides were associated with colorectal adenoma (OR 1.5; 95% CI 1.1-2.0 for the highest versus the lowest quartile, P (trend, )0.030). A stronger association was observed between three or more adenoma cases and study controls (OR 2.3; 95% CI 1.3-4.2, P (trend,) < 0.0010). After classifying the study subjects by smoking status, a significant linear risk trend was found in ever-smokers (P (trend), 0.0018) but not in never-smokers (P (trend), 0.94; P (interaction), 0.067).

CONCLUSIONS

Our results suggested that a higher serum triglyceride level may be related to a larger number of adenomas. Adenoma development involving an elevated serum triglyceride level may be modified by smoking.