Joint effects of family history and adult life dietary risk factors on colorectal cancer risk

Effects of Hydroxytyrosol on Expression of Apoptotic Genes and Activity of Antioxidant Enzymes in LS180 Cells

Purpose

Colorectal cancer is the third–most commonly occurring cancer in developed countries. Hydroxytyrosol is a potent antioxidant that has several activities, such as oxidative-stress control, inhibition of cell proliferation, and induction of apoptosis. In this study, the effect of hydroxytyrosol on the expression of genes effective in apoptosis — BAX, BCL2, CASP3, P53, PPARG, and NFE2L2 — and antioxidant-enzyme activity in LS180 cells of human colorectal cancer was investigated.

Methods

The human colorectal cancer cell line LS180 was treated with different concentrations of hydroxytyrosol for 24 hours. Expression of BAX, BCL2, CASP3, NFE2L2, PPARG, and P53 was investigated using real-time PCR. The activity of antioxidant and malondialdehyde enzymes was measured by calorimetric methods.

Results

Analysis of gene expression showed that hydroxytyrosol significantly increased the expression of CASP3 and the BAX:BCL2 ratio in treatment groups compared to the control (P<0.05). Also, hydroxytyrosol significantly reduced the expression of the NFE2L2 gene (P<0.05). Calorimetric analysis showed that hydroxytyrosol increased activity of the antioxidant enzymes catalase, superoxide dismutase, and glutathione peroxidase in treatment groups significantly more than the control group and reduced thiobarbituric acid–reactive substances on an oxidative stress index (P<0.05).

Conclusion

Hydroxytyrosol may induce apoptosis in colorectal cancer cells by increasing the expression of CASP3 gene and increasing the BAX:BCL2 ratio. Also, hydroxytyrosol may increase the activity of antioxidant enzymes and reduce the proliferation of LS180 cells by changing the antioxidant-defense system in cancer cells.

The Anticancer Efficiency of Citrullus colocynthis Toward the Colorectal Cancer Therapy

BACKGROUND

Colorectal cancer (CRC) remains a major cause of death worldwide. Chemotherapy is associated with some side effects during CRC treatment. Hence, proper employment of lower toxic and approaches exerting lowest side effects are essential. The Citrullus colocynthis (C. colocynthis) seems a potential anticancerous herbal medicine (HM) against CRC mostly via various efficient compounds.

METHODS

We performed a literature review regarding the anticancer traits of C. colocynthis against CRC. The possible active compounds, mechanisms, and combination therapies in vitro and in vivo or clinical trials have been also stated where found.

RESULTS AND CONCLUSION

The anticancerous effects of C. colocynthis has been via a variety of pathways including apoptotic pathways (increase in caspase-3 and inhibiting STAT3 function), antioxidant and anti-inflammatory (TNF-α, nitric oxide, and pro-inflammatory cytokines such as IL-6, IL-8, and IL-1α) traits, inhibition of Wnt/β-catenin signaling pathway, and antiangiogenesis and antimetastatic effects. Future studies will be promising regarding proper application of C. colocynthis compounds following their extraction.

Do alcoholic beverages, obesity and other nutritional factors modify the risk of familial colorectal cancer? A systematic review

PURPOSE

Individuals with family history of colorectal cancer are at higher risk of colorectal cancer than the general population. Until now, guidelines for familial colorectal cancer risk have only pointed at early diagnosis efforts via screening tests and surveillance, and payed scarce or no attention to lowering exposure to modifiable risk factors, notably nutritional factors.

METHODS

We conducted a systematic review of epidemiological studies investigating the associations between nutritional factors, family history of colorectal cancer, and colorectal cancer risk. From the 5312 abstracts identified until December 2016, 184 full text articles were examined for eligibility. Finally, 31 articles (21 from case-control studies, 9 from cohort studies and 1 from an intervention study) met inclusion criteria and were analyzed.

RESULTS

Mainly, the combinations of family history of colorectal cancer and higher consumptions of alcoholic beverages, red or processed meat, or overweight/obesity increase the risk of colorectal cancer. Consistently, a strong increase is observed with the combinations of family history of colorectal cancer and unhealthy dietary patterns/lifestyles. Statistically significant interactions between these nutritional factors, family history of colorectal cancer and colorectal cancer risk are reported. Other data are inconclusive and additional prospective studies are needed.

CONCLUSIONS

For the first time, our findings highlight that addressing high consumption of alcoholic beverages, red or processed meat, and overweight/obesity, and more largely the exposure to multiple unhealthy dietary/nutritional behaviors could offer new perspectives of prevention to individuals with family history of colorectal cancer. A better information of these patients and of health professionals on these nutritional modifiable risk factors is recommended.

Relationships of colorectal cancer with dietary factors and public health indicators: an ecological study

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer in Iranian women and fifth in men. The aims of this study were to investigate the relation of dietary factors and public health indicators to its development.

MATERIALS AND METHODS

The required information (2001-2006) about risk factors was obtained from the Non- Communicable Disease Surveillance Centre (NCDSC) of Iran. Risk factor data (RFD) from 89,404 individuals (15-64 years old) were gathered by questionnaire and laboratory examinations through a cross sectional study in all provinces by systematic clustering sampling method. CRC incidence segregated by age and gender was obtained from Cancer Registry Ministry of Health (CRMH) of Iran. First, correlation coefficients were used for data analysis and then multiple regression analysis was performed to control for confounding factors.

RESULTS

Colorectal cancer incidence showed a positive relationship with diabetes mellitus, hypertension, lacking or low physical activity, high education, high intake of dairy products, and non-consumption of vegetables and fruits.

CONCLUSIONS

We concluded that many dietary factors and public health indicators have positive relationships with CRC and might therefore be targets of preliminary prevention. However, since this is an ecological study limited by potential ecological fallacy the results must be interpreted with caution.

Does family history of cancer modify the effects of lifestyle risk factors on esophageal cancer? A population-based case-control study in China

A population-based case-control study on esophageal cancer has been conducted since 2003 in Jiangsu Province, China. The aim of this analysis is to provide further evidence on the relationship between family history of cancer in first-degree relatives (FH-FDRs) and the risk of esophageal cancer, and to explore the joint effects for FH-FDR with major lifestyle risk factors. A total of 1,520 cases and 3,879 controls were recruited. Unconditional logistic regression was applied for evaluating independent association as well as potential interactions between FH-FDR and lifestyle risk factors on the risk of esophageal cancer. Population attributable fraction (PAF) was calculated to quantify the proportion of cases attributable to risk factors. Results showed that with a FH-FDR of any malignant tumor or esophageal cancer, there is a 1.64- and 2.22-fold risk of esophageal cancer, respectively. Association was increased when there was more than one affected FDR (OR = 3.14) and younger age at diagnosis of relatives. Exposure of both FH-FDR and lifestyle risk factors strongly associated with esophageal cancer. Significant superadditivity interaction was found for FH-FDR with fast eating speed and diets low in fruits and vegetables. The estimation of PAF indicated that the majority of cases were attributed to lifestyle risk factors. In conclusion, it was found that FH-FDR significantly increases the risk of esophageal cancer and could modify the effect of certain lifestyle risk factors. If comprehensive lifestyle interventions are carried out within high-risk populations, there is a high probability of curbing occurrences of esophageal cancer.

Awareness of risk factors amongst first degree relative patients with colorectal cancer

BACKGROUND

The association between family history of colorectal cancer (CRC) in first degree relatives (FDRs) and the risk of developing the disease has been well established. However, little is known about the degree of awareness of CRC risk factors amongst FDRs. This study examined awareness of familial, dietary and lifestyle risk amongst FDRs.

METHOD

Consent to approach relatives was obtained from CRC patients who attended outpatients following surgery for CRC. A study specific questionnaire was sent by post to their FDRs. The dietary and lifestyle risk factors tested in the questionnaire were those promoted in CRC educational material.

RESULTS

One hundred and four questionnaires were returned out of 137 sent (76%). Fifty-nine per cent (n = 61) of FDRs were aware of their increased risk. Fifty-five per cent (n = 57) were aware of the link between CRC and smoking; however, knowledge of association of CRC with excessive alcohol consumption (32%) and lack of exercise (40%) was less well appreciated. Higher awareness scores were obtained by those with a university education (P < 0.001). Ninety four per cent believed that relatives of CRC patients were not provided with enough information as to their being at risk and risk factors.

CONCLUSIONS

This study provides an initial assessment of the awareness of CRC risk factors in a population at increased risk. It demonstrates a poor level of knowledge. Improved education strategies allowing FDRs to make dietary and lifestyle modifications that could reduce their lifetime risk of developing CRC are necessary.

Diet and vitamin or mineral supplementation and risk of rectal cancer in Canada

The study examines the relation of diet and vitamin or mineral supplementation with risk of rectal cancer. Mailed questionnaires were completed by 1 380 newly diagnosed patients with histologically confirmed rectal cancer and 3 097 population controls between 1994 and 1997 in seven Canadian provinces. Measurement included information on socio-economic status, lifestyle, diet and vitamin or mineral supplementation. We derived odds ratios and 95% confidence intervals through unconditional logistic regression. Total of consumption of vegetables, fruit and whole-grain products did not reduce the risk of rectal cancer. Consumption of cruciferous vegetables was inversely associated with risk of rectal cancer among women only, as did chicken intake among men. The strongest dietary association with increased rectal cancer risk appeared in males with increasing total fat intake and in females with bacon intake. Vitamin and mineral supplementation showed significant inverse associations with rectal cancer in women only. These findings suggest that dietary risk factors for rectal cancer in women may differ from those in men.

Diet and vitamin or mineral supplementation and risk of colon cancer by subsite in Canada

The study assesses the association of diet and vitamin or mineral supplementation with risk of proximal or distal colon cancer. Mailed questionnaires were completed by 1723 newly diagnosed, histologically confirmed colon cancer cases and 3097 population controls between 1994 and 1997 in seven Canadian provinces. Measurement included information on socio-economic status, physical activity, smoking habits, alcohol use, diet and vitamin or mineral supplementation. Odds ratios and 95% confidence intervals were derived through unconditional logistic regression. Linear regression was used to examine that dietary factors affect body mass index. The strongest positive associations between colon cancer risk and increasing total fat intake were observed for proximal colon cancer in men and for distal colon cancer in both men and women. Increased consumption of vegetables, fruit and whole-grain products did not reduce the risk of colon cancer. A modest reduction in distal colon cancer risk was noted in women who consumed yellow-orange vegetables. Significant positive associations were observed between proximal colon cancer risk in men and consumption of red meat and dairy products, and between distal colon cancer risk in women and total intake of meat and processed meat. We also saw strong associations between bacon intake and both subsites of colon cancer in women. When men were compared with women directly by subsite however, the results did not show a corresponding association. A significantly reduced risk of distal colon cancer was noted in women only with increasing intake of dairy products and of milk. Among men and women taking vitamin and mineral supplements for more than 5 years, significant inverse associations with colon cancer were most pronounced among women with distal colon cancer. These findings suggest that dietary risk factors for proximal colon cancer may differ from those for distal colon cancer.

Epidemiological changes in colorectal cancer in Shiraz, Iran: 1980-2000

BACKGROUND

The present study was performed to determine trends in colorectal cancer rates over the past two decades (1970-80 vs 1990-2000) with in a main referral centre in Shiraz, Iran.

METHODS

The Cancer Registry data on all colorectal cancer cases from 1970 to 2000 in Shiraz, Iran, were analysed. Demographic characteristics, clinical features, cancer site and type and stage of cancer were compared in the populations of two different decades.

RESULTS

The age-adjusted incidence of colorectal cancer per 100,000 population per year increased in men from a mean annual incidence of 1.61 in the decade 1970-80 to 4.2 in 1990-2000 (P < 0.05), and in women from 2.35 to 2.72 (P < 0.05). In 1970-80, patients over 60 years had 62.5% of all the colorectal cancers, which decreased to 30% in 1990-2000 (P < 0.05). The distribution of right and left sided cancers were almost equal and showed no significant difference between the two decades (P > 0.05).

CONCLUSION

A marked increase in the incidence of colorectal cancer has been shown in Shiraz. Also, the marked increase in the incidence of colorectal cancer in the 40-60-year-old age group shown in the present study necessitates a more detailed work-up in younger age group patients.

Family History and Environmental Risk Factors for Colon Cancer

Background: We analyzed the joint effect of environmental risk factors and family history of colorectal cancer on colon cancer. Methods: We used data from a case-control study conducted in northern Italy between 1992 and 1996 including 1225 cases with colon cancer and 4154 controls. We created a weighed risk factor score for the main environmental risk factors in this population (positive family history, high education, low occupational physical activity, high daily meal frequency, low intake of fiber, low intake of calcium, and low intake of β-carotene). Results: Compared with the reference category (subjects with no family history of colorectal cancer and in the lowest tertile of the risk factor score), the odds ratios of colon cancer were 2.27 [95% confidence interval (CI) = 1.89–2.73] for subjects without family history and in the highest environmental risk factor score, 3.20 (95% CI = 2.05–5.01) for those with family history and low risk factor score, and 7.08 (95% CI = 4.68–10.71) for those with family history and high risk factor score. The pattern of risk was similar for men and women and no meaningful differences emerged according to subsite within the colon. Conclusions: Family history of colorectal cancer interacts with environmental risk factors of colon cancer.

Sulforaphane inhibits growth of a colon cancer cell line

OBJECTIVE

The consumption of cruciferous vegetables has a protective effect on the development of colorectal cancer. The phytochemical Sulforaphane is an isothiocyanate found almost exclusively in cruciferous vegetables. We have studied the effect of Sulforaphane on cell proliferation of an HT-29 colon cancer cell line.

MATERIALS AND METHODS

HT-29 colon cancer cells were cultured in 96-well microtitre plates. Sulforaphane (in concentrations ranging from 0.01 to 0.1 mmol) were added to the wells. Cell proliferation was measured using the colourimetric assay technique.

RESULTS

The proliferation of colon cancer cells was significantly reduced by Sulforaphane at concentrations of >/=0.02 mmol.

CONCLUSION

These findings may help explain the epidemiologically proven protective effect of vegetables against colon cancer.

The variable effect on proliferation of a colon cancer cell line by the citrus fruit flavonoid Naringenin

OBJECTIVE

Naringenin, a naturally occurring flavonoid found in citrus fruits, is known to have anticarcinogenic properties. We have examined the effect of Naringenin on cell proliferation of an HT-29 colon cancer cell line.

METHODS

HT-29 colon cancer cells were cultured in 96-well tissue culture plates. Naringenin concentrations ranging from 0.02 to 2.85 mmol were added to the wells of the Test group. The Control group contained all the elements present in the Test group with the exception of Naringenin. Cell proliferation was measured by colourimetric assay using the 2% WST-1 cell proliferation kit.

RESULTS

Significant inhibition of cell proliferation was observed in HT29 colon cancer cells exposed to Naringenin at doses greater than 0.71 mmol.

CONCLUSIONS

These results suggest a potential role for citrus fruits as a source of chemoprotective agents for colon cancer.