Colorectal cancer screening: Time for action in Iran

Association study of Bif-1 gene expression with histopathological characteristics and hormone receptors in breast cancer

BACKGROUND

Breast cancer is a heterogeneous disease that has various clinical outcomes. Bax-interacting factor-1 (Bif-1) is a member of the endophilin B family that generates the pro-apoptotic BCL2-Associated X (BAX) protein in response to apoptotic signals. Lack of Bif-1 inhibits the intrinsic pathway of apoptosis and enhancements the risk of tumor genesis. The present study aimed to investigate the relationship between hormone receptors (ER, PR, and HER2) status and different levels of Bif-1 gene expression in breast cancer patients.

METHODS

Bif-1 gene expression was evaluated in 50 breast cancer tumors and 50 normal breast mammary tissues using the SYBR Green real-time RT-PCR technique. Multivariate and univariate analyses were used to appraise the relationship between the prognostic significance of the Bif-1 gene using SPSS software. In this study, the Bif-1 was selected as a candidate for a molecular biomarker and its expression status in breast cancer patients with hormone receptors (ER, RR, and HER2) compared to patients without these hormone receptors.

RESULTS

The study showed that the relative expression of the Bif-1 gene in tissues of patients with hormone receptors in breast cancer compared to those without hormone receptors was not statistically significant. The expression levels of the Bif-1 gene in different groups were evaluated for hormone receptor status. No significant relationship was found between the Bif-1 gene expression and hormone receptors (ER, PR, and HER2) (p > 0.05).

CONCLUSION

Bif-1 gene expression may be a useful prognostic marker in breast cancer.

The Combination of Zerumbone and 5-FU: A Significant Therapeutic Strategy in Sensitizing Colorectal Cancer Cells to Treatment

Objectives. Chemotherapy is considered to be essential in the treatment of patients with colorectal cancer (CRC), but drug resistance reduces its efficacy. Many patients with advanced CRC eventually show resistance to 5-fluorouracil (5-FU) therapy. Synergistic and potentiating effects of combination therapy, using herbal and chemical drugs, can improve patients’ response. Zerumbone (ZER), which is derived from ginger, has been studied for its growth inhibitory function in various types of cancer. Methods. The cytotoxic effects of ZER and 5-FU alone and their combination, on the SW48 and HCT-116 cells, were examined, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). The mRNA and protein levels of β-catenin, survivin, and vimentin were measured in treated CRC cells, using qRT-PCR and western blot. Colony formation assay, scratch test, and flow cytometry were performed to detect the changes of proliferation, migration, and apoptosis. Key Findings. In HCT-116- and SW48-treated cells, the proliferation, the gene and protein expression levels of the markers, the migration, the colony formation, and the survival rates were all significantly reduced compared to the control groups, and the sharpest decline was observed in the 5-FU+ZER treatment groups. Conclusions. Combination therapy has shown promising results in CRC cells, especially in drug-resistant cells.

The Role, Function, and Mechanism of Long Intergenic Noncoding RNA1184 (linc01184) in Colorectal Cancer

Background

Long intergenic noncoding RNA1184 (linc01184) has been recently discovered; however, its role in human diseases is limited to date. The present study is aimed at investigating the expression pattern and mechanism of linc01184 in colorectal cancer (CRC) tumorigenesis.

Methods

The expression of linc01184 in CRC tissues and cell lines was compared with that in normal controls. The functions of linc01184 in CRC cells were identified by overexpression and small interfering RNA (siRNA) approaches in vitro. Meanwhile, the target gene prediction software, luciferase reporter, RNA pull-down, and western blotting assays were used to analyze the oncogenic mechanism.

Results

We found that linc01184 was obviously upregulated in CRC tissues and cells when compared to normal controls, and its upregulation had a positive association with the CRC progression. linc01184 knockdown significantly suppressed CRC cell proliferation and invasion and promoted apoptosis. Besides, linc01184 acted as a competitive endogenous RNA (ceRNA) by directly binding to microRNA-331 (miR-331), and its overexpression resulted in notable increases of human epidermal growth factor receptor 2 (HER2), phosphorylated Ser/Thr kinases (p-Akt), and extracellular regulated protein kinase 1/2 (p-ERK1/2) at posttranscriptional levels in CRC cells, which were antagonized by miR-331.

Conclusions

The findings reveal for the first time that linc01184 is an enhancer for the proliferation and invasion of CRC by functioning as a ceRNA through the linc01184-miR-331-HER2-p-Akt/ERK1/2 pathway regulatory network.

Increasing the expression of programmed death ligand 2 (PD-L2) but not 4-1BB ligand in colorectal cancer cells

Immune checkpoint (ICP) molecules modulate the immune response by either inducing or preventing T cell activation. Over-expression of some ICPs on malignant cells has been shown to regulate anti-tumor immune responses. We aimed to investigate the expression levels of two immune checkpoint molecules which have not been studied extensively in patients with colorectal cancer (CRC). Programmed Death Ligand 2 (co-inhibitory) and 4-1BB ligand (co-stimulatory) were assessed in tumor tissues of CRC patients compared to the adjacent normal tissues. Following tissue excision during surgical operation from 21 CRC patients, RNA extraction, cDNA synthesis and semi-quantitative real-time PCR were done for measuring the expressions of PD-L2 and 4-1BBL genes. In protein level, indirect immunohistochemistery (IHC) was performed on tissue sections. We revealed that PD-L2 was expressed in about 81% CRCs and insignificantly correlated with the tumor differentiation grade. Although a 3.25-fold change in the gene expression of PD-L2 was found in tumor tissues compared to the adjacent normal tissues (P = 0.005), but decreased level of 4-1BBL in counterpart tissues was not significant. Our results were confirmed by IHC for PDL-2 (P = 0.02) and 4-1BBL, however it was not statistically significant for the latter one. Although not significant, we could find an association between the elevated expression of PD-L2 and the tumor differentiation grade. Increased expression of negative regulator of the anti-tumor immune responses like PD-L2, as a prominent way of tumor escape, can be considered for cancer immunotherapy approaches in CRC patients using blocking monoclonal antibodies.

Gut Bacteria and their Metabolites: Which One Is the Defendant for Colorectal Cancer?

Colorectal cancer (CRC) is a worldwide health concern which requires efficient therapeutic strategies. The mechanisms underlying CRC remain an essential subject of investigations in the cancer biology field. The evaluation of human microbiota can be critical in this regard, since the disruption of the normal community of gut bacteria is an important issue in the development of CRC. However, several studies have already evaluated the different aspects of the association between microbiota and CRC. The current study aimed at reviewing and summarizing most of the studies on the modifications of gut bacteria detected in stool and tissue samples of CRC cases. In addition, the importance of metabolites derived from gut bacteria, their relationship with the microbiota, and epigenetic modifications have been evaluated.

Socio-cognitive determinants of colorectal cancer screening uptake: An application of intervention mapping approach

Background: Fecal occult blood test (FOBT) is one of the common screening tests for colorectal cancer. This study was designed to determine the socio-cognitive determinants related to FOBT uptake for colorectal cancer screening based on intervention mapping (IM).

Methods: A total of 500 individuals aged over 50 years were randomly selected to participate in this study in Kermanshah, Iran, in 2016. Data were collected by interviews based on a questionnaire and analyzed by SPSS16 using bivariate correlation, linear, and logistic regression models.

Results: Of the 500 respondents, 468 (93.6%) signed the consent form and voluntarily participated in the study. Almost 11.1% of the participants had a history of FOBT uptake. Socio-cognitive variables accounted for 38% of the variation in the outcome measure of the intention to uptake FOBT. Perceived self-efficacy (OR = 3.345 & 95% CI: 1.342, 8.339), perceived susceptibility (OR = 2.204& 95% CI: 1.320, 3.680), attitude (OR = 1.674& 95% CI: 1.270, 2.137), and perceived severity (OR = 1.457& 95% CI: 0.954, 2.224) were the strongest predictors of fecal occult blood test uptake.

Conclusion: IM-based analysis of behavior may provide insights to design interventions for modifying individuals’ beliefs about the usefulness of FOBT uptake to prevent colorectal cancer.

Role of gut microbiota in the pathogenesis of colorectal cancer; a review article

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers worldwide. Lifestyle is identified as one of the most important risk factors for CRC, especially in sporadic colorectal cancer. The natural composition of the gut microbiota changes rapidly during the first decade of life. Maintaining homeostasis in the gut is essential as structural and metabolic functions of the commensal microbiota inhibit gut colonization of pathogens. Dysbiosis, imbalance in function or structure of gut microbiota, has been associated with a variety of diseases, such as colorectal cancer. The aim of this review was to investigate the possible links between the dysbiosis in gut microbiota and colorectal cancer, and the potential role of anaerobic gut microbiota in the pathogenesis of colorectal cancer. Based on this review, various studies have shown that some of the gut microbiota such as anaerobic bacteria significantly increased in CRC patients, but we suggest more investigations are required to assess the importance of these bacteria and their metabolites in the pathogenesis of CRC are required.

Cancer Screening Awareness and Practice in a Middle Income Country; A Systematic Review from Iran

Objective: Ageing population and noticeable changes in lifestyle in developing countries like Iran caused an increase in cancer incidence. This requires organized cancer prevention and screening programs in population level, but most importantly community should be aware of these programs and willing to use them. This study explored existing evidence on public awareness and practice, as well as, adherence to cancer screening in Iranian population. Methods: Major English databases including Web of Science, PubMed, Scopus, and domestic Persian databases i.e., SID, Magiran, and Barakat search engines were searched. All publications with focus on Iranian public awareness about cancer prevention, screening, and early detection programs which were published until August 2015, were explored in this systematic review. For this purpose, we used sensitive Persian phrases/key terms and English keywords which were extracted from medical subject headings (MeSH). Taking PRISMA guidelines into considerations eligible documents, were evaluated and abstracted by two separate reviewers. Results: We found 72 articles relevant to this topic. Screening tests were known to, or being utilized by only a limited number of Iranians. Most Iranian women relied on physical examination particularly self-examination, instead of taking mammogram, as the most standard test to find breast tumors. Less than half of the average-risk adult populations were familiar with colorectal cancer risk factors and its screening tests, and only very limited number of studies reported taking at least one time colonoscopy or FOBT, at most 5.0% and 15.0%, respectively. Around half of women were familiar with cervical cancer and Pap-smear test with less than 45% having completed at least one lifetime test. The lack of health insurance coverage was a barrier to participate in screening tests. Furthermore some people would not select to be screened only because they do not know how or where they can receive these services. Conclusion: Low awareness and suboptimal use of screening tests in Iran calls for effective programs to enhance intention and compliance to screening, improving the patient-physician communication, identifying barriers for screening and providing tailored public awareness and screening programs.

Assessment of Bone Morphogenetic Protein 3 Methylation in Iranian Patients with Colorectal Cancer

BACKGROUND

Colorectal cancer (CRC) is a common cancer that results in outstanding morbidity and mortality worldwide. DNA methylation is one of the most important epigenetic events that is thought to occur during the early stages of oncogenic transformation especially in CRC. The aim of this study was to investigate whether hypermethylation of bone morphogenetic protein 3 (BMP3) in tissue samples is implicated in Iranian patients with CRC.

METHODS

From fresh frozen tissue samples of 30 patients with CRC, the DNA was isolated, treated with sodium bisulfite and analyzed by methylation-specific polymerase chain reaction with primers specific for methylated or unmethylated promoter sequences of the BMP3 gene. Demographic characteristics of the patients including age, sex, tumor grade, location, stage, and TNM classification were evaluated and the relationship between hypermethylation of the gene and clinicopathological features was analyzed.

RESULTS

Methylation of the BMP3 promoter was often present in the DNA extracted from the tumoral tissues. A sensitivity of 56.66% and specificity of 93.3% were attained in the detection of colorectal neoplasia.

CONCLUSION

We assumed that solely BMP3 methylation analysis in our population is not sufficient to select the gene as a screening biomarker and it should be considered in combination with other markers to screen for detection of colorectal cancer.

Survival of colorectal cancer patients in the presence of competing-risk

BACKGROUND

Colorectal cancer (CRC) is considered to be a main cause of malignancy-related death in the world, being commonly diagnosed in both men and women. It is the third leading cause of cancer dependent death in the world and there are one million new cases diagnosed per year. In Iran the incidence of colorectal cancer has increased during the last 25 years and it is the fifth cause of cancer in men and the third in women.

MATERIALS AND METHODS

In this article we analyzed the survival of 475 colorectal patients of Taleghani hospital in Tehran with the semi-parametric competing-risks model.

RESULTS

There were 55% male cases and at the time of the diagnosis most of the patients were between 48 and 67 years old. The probability of a patient death from colorectal cancer with survival of more than 25 years was about 0.4. Body mass index, height, tumour site and gender had no influence.

CONCLUSIONS

According to these data and by using semi-parametric competing-risks method, we found out that only age at diagnosis has a significant effect on these patient survival time.

Evaluation of prognostic factors effect on survival time in patients with colorectal cancer, based on Weibull Competing-Risks Model

AIM

The aim of this study was to assess the association between survival of patients with colorectal cancer and prognostic factors in a competing risk parametric model using Weibull distribution.

BACKGROUND

The prognosis of colorectal cancer is relatively good in terms of survival time. In many prognostic studies, patients may be exposed to several types of competing events. These different causes of death are called competing risks.

METHODS

Data was recorded from 372 patients with colorectal cancer who registered in the Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences (Tehran, Iran) from 2004 to 2015 in a retrospective study. Analysis was performed using competing risks model and Weibull distribution. Software used for data analysis was R, and significance level was regarded as 0.05.

RESULTS

The result indicated that, at the end of follow-up, 111 (29.8%) deaths were from colorectal cancer and 14 (3.8%) deaths were due to other diseases. The average body mass index (BMI) was 24.61(SD 3.98). The mean survival time for a patient in 372 was 62.05(SD 48.78) month with median equals to 48 months. According to competing-risks method, only stageIII (HR, 1.69; 95% CI, 1.246-2.315 ), stageIV( HR, 4.51; 95% CI,2.91-6.99 ) and BMI( HR, 0.96; 95% CI, 0.96-0.975) have a significant effect on patient's survival time.

CONCLUSION

This study indicated pathologic stage (III,IV) and BMI as the prognosis, using a Weibull model with competing risks analysis, while other models without the competing events lead to significant predictors which may be due to over-estimation.

Knowledge about Colorectal Cancer in Northern Iran: a Population-Based Telephone Survey

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignancies of the gastrointestinal tract. The aim of this study was to assess the general knowledge of CRC in individuals living in Rasht, Iran, using a population-based cross-sectional telephone survey.

MATERIALS AND METHODS

A total of 1557 participants between 18 and 80 years of age were interviewed using random sampling from the telephone directory. Knowledge of risk factors, symptoms, diagnosis, and prevention of CRC was assessed using a validated questionnaire.

RESULTS

The mean knowledge level of the 1,557 respondents (average age 46 y) was 13.5 ± 4.29 (maximum possible score = 26), and 46.4% (722/1,557) of the subjects achieved grades lower than the mean score. The mean scores for knowledge of symptoms and risk factors were 3.97 ± 1.83 (range: 0-7) and 5.17 ± 1.65 (range: 0-9), respectively. Older age, higher education, and employment were significantly associated with better scores for recognition of risk factors and warning symptoms. The majority of subjects correctly identified weight loss (70.2%; 1,093/1,557) and rectal bleeding (63.3%; 986/1,557) as symptoms of CRC, and that smoking (85.9%; 1,337/1,557) and a low- fiber diet (73.4%; 1,143/1,557) were risk factors. Approximately half of the subjects noted increasing age, genetic background and fried food as other risk factors. A considerable number (54.8%; 853/1,557) identified colonoscopy as a screening method for detecting CRC in asymptomatic patients. However, a third of the subjects in the target group for screening (≥ 50 y) were not interested in undergoing screening, primarily due to a lack of symptoms.

CONCLUSIONS

Our results suggest that the knowledge of CRC is poor among the public, and therefore greater attempts should be made to increase awareness. Public education emphasizing the risk factors and symptoms of CRC, as well as the importance of regular screening regardless of the presence of symptoms, may help to reduce CRC morbidity and mortality.

An Apta-Biosensor for Colon Cancer Diagnostics

This paper reports the design and implementation of an aptasensor using a modified KCHA10a aptamer. This aptasensor consists of a functionalized electrodes using various materials including 11-mercaptoandecanoic acid (11-MUA) and modified KCHA10a aptamer. The HCT 116, HT 29 and HEp-2 cell lines are used in this study to demonstrate the functionality of aptasensor for colon cancer detection purposes. Flow cytometry, fluorescence microscopy and electrochemical cyclic voltammetry are used to verify the binding between the target cells and aptamer. The limit of detection (LOD) of this aptasensor is equal to seven cancer cells. Based on the experimental results, the proposed sensor can be employed for point-of-care cancer disease diagnostics.

High rate of advanced colorectal polyps in a 10-year-long retrospective study in Qazvin, Iran

BACKGROUND

Polyps are common lesions in the gastrointestinal (GI) tract. Colon cancer is mostly a result of progression from polyps. The present study aimed to evaluate demographic, clinical, and histological characteristics of colorectal polyps in Iran, particularly neoplastic and advanced types.

MATERIALS AND METHODS

Over a period of 10 years, specimens of all colorectal polyps obtained from colonoscopy were studied. The variables subjected to statistical analysis were age, sex, and the chief clinical complaint of the patients who underwent colonoscopy, their motivation, and the site, size, and histological types of detected polyps. The level of significance was set at p value<0.05.

RESULTS

Data were obtained from a total of 352 patients. No difference was seen between male and female patients regarding histological types. Only in nine patients was screening the reason for colonoscopy. Almost two-thirds (66.2%) of the polyps were neoplastic. Familial polyposis syndrome and inflammatory bowel disease were seen in 4.3% and 3.0% of the patients with neoplastic polyps, respectively. Sites of polyps were the sigmoid, rectum, and descending colon in 40.1%, 34.5%, and 17% of the cases, respectively. The advanced type made up 58.8% of neoplastic polyps. Only 3.6% of the patients undergoing colonoscopy in the study period had biopsied polyps.

DISCUSSION

No difference was observed between male and female patients in terms of overall incidence of polyps, histological and anatomical profiles, and mean age distribution. Anatomical and histological profiles agreed with the studies performed in areas with a low risk of colon cancer. The findings show that colonoscopy was not performed when it was necessary. A meaningful increase in the number polyp biopsy cases and a corresponding decrease in polyp size in the last few years of the study can be associated with the presence of more GI specialist clinicians in hospital centers, and this holds out much hope for the further improvement of the situation in the future.

Recurrence and Five -Year Survival in Colorectal Cancer Patients After Surgery

BACKGROUND

Colorectal cancer (CRC) is a common malignancyworldwide and its outcome is most closely related to the extent of disease at presentation. Early diagnosis of an asymptomatic recurrence increases the likelihood of a complete surgical resection.

OBJECTIVES

The aim of this study was to evaluate the incidence of colorectal cancer recurrence and survival rate within 5 years, after surgery.

PATIENTS AND METHODS

During the 9-year period since 21st Mar, 2004 to 20th Mar, 2013, patients whose primary colorectal cancer were resected in Taleghani hospital, Tehran, Iran were selected in a historical cohort. The necessary data such as demographic, age, gender, family history of CRC, site and size of tumor, stage of tumor, operation details, histological results, treatment method, histopathologic, etc. were collected. Then the recurrence and survival of colorectal cancer within 5 years after operation and their risk factors were evaluated. P value less than 0.05 were considered significant. All analysis was done using SPSS software.

RESULTS

A total of 107 patients underwent resection for colorectal cancer during the study period, with mean age of 53.50 ± 12.68 years (range 24 - 76 years), survival rate of 73.8% (rectum 70.0% and colon 75.9%), and mean survival time of 142.17 ± 21.60 month. The recurrence rate of CRC patients, during five years after surgery was 5.7%. Regional lymph nodes, Distance metastasis and Adjuvant therapy were significant prognosis factors of survival after surgery.

CONCLUSIONS

The rate of recurrence in Iranian patients was low, which could be due to improvement of exactness and expertise of surgeons or better adjuvant therapy. The significant association between survival and adjuvant therapy clarifies this finding. Early diagnosis and primary detection could increase the rate of survival.

Colorectal cancer in iran: molecular epidemiology and screening strategies

Purpose. The increasing incidence of colorectal cancer (CRC) in the past three decades in Iran has made it a major public health burden. This study aimed to report its epidemiologic features, molecular genetic aspects, survival, heredity, and screening pattern in Iran. Methods. A comprehensive literature review was conducted to identify the relevant published articles. We used medical subject headings, including colorectal cancer, molecular genetics, KRAS and BRAF mutations, screening, survival, epidemiologic study, and Iran. Results. Age standardized incidence rate of Iranian CRCs was 11.6 and 10.5 for men and women, respectively. Overall five-year survival rate was 41%, and the proportion of CRC among the younger age group was higher than that of western countries. Depending on ethnicity, geographical region, dietary, and genetic predisposition, mutation genes were considerably diverse and distinct among CRCs across Iran. The high occurrence of CRC in records of relatives of CRC patients showed that family history of CRC was more common among young CRCs. Conclusion. Appropriate screening strategies for CRC which is amenable to early detection through screening, especially in relatives of CRCs, should be considered as the first step in CRC screening programs.

Burden of gastrointestinal cancer in Asia; an overview

The cancers in the digestive system including gastric cancer, colorectal cancer, liver cancer, esophageal cancer and pancreatic cancer are one of the most common cancers in Asia. The burden of GI cancer is increasing in Asia because of aging, growth of the population and the risk factors including smoking, obesity, changing lifestyle and high prevalence of H pylori, HBV and HCV. In most Asian countries, cancer control programs or early detection and treatment services are limited despite this increase. There are many people in the developing countries inside Asia who have no health insurance and many of them are too poor to go for screening tests, early detection or medical treatments. Therefore, it is important for the health organizations and governments in each country to recognize these groups and reduce the incidence and mortality of gastrointestinal cancers, using simple and economic screening test, vaccination and changing risk factors such as smoking, diet and lifestyle by education programs.

Knowledge and perception toward colorectal cancer screening in east of Iran

BACKGROUND

Colorectal Cancer (CRC) is the third most common cancer in Iran and its early detection is necessary. This study is based on perception of people in the east of Iran toward CRC screening.

METHODS

In a cross-sectional study, 1060 randomly selected individuals who referred to Razavi Hospital of Mashhad, Iran, between September the 1(st), 2012 and February the 28(th), 2013 as patients or their visitors involved in an interview to fill a questionnaire on CRC screening.

RESULTS

The participants' age ranged from 40 to 88 years (mean= 55). More than 90% had no knowledge of CRC and screening tests. The most cited reasons for not having screening tests were "did not have any problem" and "did not think it was needed". Although, older people had more knowledge of CRC (P= 0.033), there was no relationship between gender, health insurance status, family history of individuals and their knowledge about CRC (P> 0.050). Employment, education and higher income had positive effect on the perception of people toward CRC screening (P< 0.050).

CONCLUSION

Lack of knowledge in people in lower socio-economical class with limited literacy is the most important barrier to CRC screening. As such, designing educational programs involving physicians and media is important to improve CRC screening rates.

Mortality trends of gastrointestinal cancers in Iranian population

AIM

The aim of this study was to evaluate the mortality rates and trends from Gastrointestinal (GI) cancer in Iranian population from 1995 to 2003.

BACKGROUND

Cancer is the third most common cause of death in Iran. Gastrointestinal cancer is the most important causes of mortality due to cancer. The cancer mortality data is important to monitor the effects of screening program, earlier diagnosis, demographic data and other prognostic factors.

PATIENTS AND METHODS

National death Statistic Reported by the Ministry of Health and Medical Education (MOH&ME) from 1995 to 2003, stratified by age group, sex, and cause of death is included in this analysis. Colorectal cancer (CRC) [ICD-9; 153-154], Gastric cancer (GC) [ICD-9; 151], Pancreas cancer (PC) [ICD-9; 25], Esophageal cancer (EC) [ICD-9; C15] and Hepatocellular carcinoma (HCC) [ICD-9; 20] were expressed as the annual mortality rates/100,000, general and/or per gender, and age group.

RESULTS

The cause specific mortality rate of CRC slightly increased during the years under study and for GC and EC showed a sharp increasing. In contrast, the mortality rate of PC decreased slightly during the years under the study. The rate of HCC mortality moderately increased. All mortality rates were higher for male than female.

CONCLUSION

Our study indicated remarkable increasing trends in mortality of GI cancer in Iran specifically for CRC and GC. Developing for a GC and EC for both primary prevention and early detection programs and providing the facilities for CRC screening, would be the options to control the mortality and burden of GI cancers in the future.

MUTYH the base excision repair gene family member associated with colorectal cancer polyposis

COLORECTAL CANCER IS CLASSIFIED IN TO THREE FORMS

sporadic (70-75%), familial (20-25%) and hereditary (5-10%). hereditary colorectal cancer syndromes classified into two different subtypes: polyposis and non polyposis. Familial Adenomatous polyposis (FAP; OMIM #175100) is the most common polyposis syndrome, account for <1% of colorectal cancer incidence and characterized by germline mutations in the Adenomatous polyposis coli (APC, 5q21- q22; OMIM #175100). FAP is a dominant cancer predisposing syndrome which 20-25% cases are de novo. There is also another polyposis syndrome; MUTYH associated polyposis (MAP, OMIM 608456) which it is caused by mutation in human Mut Y homologue MUTYH (MUTYH; OMIM 604933) and it is associated with multiple (15-100) colonic adenomas. In this paper we discuss MUTYH mechanism as an important member of Base Excision Repair (BER) family and its important role in polyposis condition.

Increased burden of colorectal cancer in Asia

The incidence and mortality of colorectal cancer (CRC) is rising rapidly in Asia. It seems that ethnicity has an important etiological role in CRC in Asia. However the incidence, anatomical distribution and mortality of CRC among Asian populations are not different from those in Western countries. There is little support by health authorities for CRC screening and very low public awareness of this emerging epidemic in Asia. The increasing rate of CRC in Asia means that we need to take action immediately to prevent CRC and to diagnose the disease at the early stages by introducing CRC screening in countries at high risk of an increasing burden of CRC.