• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.145-150
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• 2014

MicroRNAs (miRNAs) negatively regulate gene expression and act as tumor suppressors or oncogenes in oncogenesis. The association between a single nucleotide polymorphism (SNP) in miR-146a rs2910164 and susceptibility to digestive system cancers was inconsistent in previous studies. In this study, we conducted a literature search of PubMed to identify all relevant studies published before August 31, 2013. A total of 21 independent case-control studies were included in this updated meta-analysis with 9,558 cases and 10,614 controls. We found that the miR-146a rs2910164 polymorphism was significantly associated with decreased risk of digestive system cancers in an allele model (OR=0.90, 95%CI 0.87-0.94), homozygote model (OR=0.84, 95%CI 0.77-0.91), dominant model (OR=0.90, 95%CI 0.84-0.96), and recessive model (OR=0.85, 95%CI 0.79-0.91), while in a heterozygous model (OR = 0.99, 95% CI 0.89-1.11) the association showed marginal significance. Subgroup analysis by cancer site revealed decreased risk in colorectal cancer above allele model (OR=0.90, 95%CI 0.83-0.97) and homozygote model (OR=0.85, 95%CI 0.72-1.00). Similarly, decreased cancer risk was observed when compared with allele model (OR=0.87, 95%CI 0.81-0.93) and recessive model (OR=0.81, 95%CI 0.72-0.90) in gastric cancer. When stratified by ethnicity, genotyping methods and quality score, decreased cancer risks were also observed. This current meta-analysis indicated that miR-146a rs2910164 polymorphism may decrease the susceptibility to digestive system cancers, especially in Asian populations.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2269-2272
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• 2013

Matrix metalloproteinases (MMPs) degrade various components of the extracellular matrix and functional polymorphisms in encoding genes may contribute to genetic susceptibility to many cancers. Up to now, associations between MMP-7 (-181A>G) and digestive system cancer risk have remained inconclusive. To better understand the role of the MMP-7 (-181A>G) genotype in digestive cancer development, we conducted this comprehensive meta-analysis encompassing 3,518 cases and 4,596 controls. Overall, the MMP-7 (-181A>G) polymorphism was associated with higher digestive system cancer risk on homozygote comparison (GG vs. AA, OR=1.21, 95% CI = 1.12-1.60) and in a dominant model (GG/GA vs. AA, OR=1.16, 95% CI =1.03-1.46). On subgroup analysis, this polymorphism was significantly linked to higher risks for gastric cancer (GG vs. AA, OR=1.22, 95% CI = 1.02-1.46; GA vs. AA, OR=1.82, 95% CI =1.16-2.87; GG/GA vs. AA, OR=1.13, 95% CI =1.01-1.27; GG vs. GA/AA, OR= 1.25, 95% CI = 1.06-2.39. We also observed increased susceptibility to colorectal cancer and esophageal SCC in both homozygote (OR = 1.13, 95% CI = 1.06-1.26) and heterozygote comparisons (OR = 1.45, 95% CI = 1.11-1.91). In the stratified analysis by controls, significant effects were only observed in population-based studies (GA vs. AA, OR=1.16, 95% CI=1.08-1.50; GA/AA vs. GG, OR=1.10, 95% CI=1.01-1.72). According to the source of ethnicity, a significantly increased risk was found among Asian populations in the homozygote model (GG vs. AA, OR=1.40, 95% CI=1.12-1.69), heterozygote model (GA vs. AA, OR=1.26, 95% CI=1.02-1.51), and dominant model (GG/GA vs. AA, OR=1.18, 95% CI=1.08-1.55). Our findings suggest that the MMP-7 (-181A>G) polymorphism may be a risk factor for digestive system cancer, especially among Asian populations.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8279-8285
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• 2014

A meta-analysis incorporating 34 case-control studies from 19 articles involving 12,197 cases and 13,488 controls was conducted to assess the effects of three genetic variants of Toll-like receptor 9 (TLR9): rs187084, rs352140, and rs5743836. Studies on associations between TLR9 polymorphisms and cancer risk were systematically searched in electronic databases. The reported odds ratios (OR) and 95% confidence intervals (CI) were pooled to assess the strength of any associations. The results showed that the rs187084 polymorphism was significantly associated with an increased risk of cancer (CC vs TC+TT: OR=1.14, 95% CI=1.02-1.28), specifically cervical cancer (C vs T: OR=1.19, 95% CI=1.05-1.34; TC vs TT: OR=1.32, 95% CI=1.10-1.58; CC vs TT: OR=1.31, 95% CI=1.03-1.68; CC+TC vs TT: OR=1.32, 95% CI=1.11-1.56), and that this association was significantly positive in Caucasians (CC vs. TC+TT: OR=1.18, 95% CI=1.01-1.38). The rs352140 polymorphism had a protective effect on breast cancer (GA vs GG: OR=0.77, 95% CI=0.66-0.89), whereas the rs5743836 polymorphism was likely protective for digestive system cancers (CC+TC vs TT: OR=0.81, 95% CI=0.66-0.98). In conclusion, our results suggest that the rs187084 polymorphism may be associated with an elevated cancer risk, whereas polymorphisms of rs352140 and rs5743836 may play protective roles in the development of breast and digestive system cancers, respectively. From the results of this meta-analysis further large-scale case-control studies are warranted to verify associations between TLR9 polymorphisms and cancer.

• Journal of Cancer Prevention
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• v.22 no.1
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• pp.1-5
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• 2017

Pancreatic cancer is a highly aggressive malignant tumor of the digestive system and radical resection, which is available to very few patients, might be the only possibility for cure. Since therapeutic choices are limited at the advanced stage, prevention is more important for reducing incidence in high-risk individuals with family history of pancreatic cancer. Epidemiological studies have shown that a high consumption of fish oil or ${\omega}3-polyunsaturated$ fatty acids reduces the risk of pancreatic cancers. Dietary fish oil supplementation has shown to suppress pancreatic cancer development in animal models. Previous experimental studies revealed that several hallmarks of cancer involved in the pathogenesis of pancreatic cancer, such as the resistance to apoptosis, hyper-proliferation with abnormal $Wnt/{\beta}-catenin$ signaling, expression of pro-angiogenic growth factors, and invasion. Docosahexaenoic acid (DHA) is a ${\omega}3-polyunsaturated$ fatty acid and rich in cold oceanic fish oil. DHA shows anti-cancer activity by inducing oxidative stress and apoptosis, inhibiting $Wnt/{\beta}-catenin$ signaling, and decreasing extracellular matrix degradation and expression of pro-angiogenic factors in pancreatic cancer cells. This review will summarize anti-cancer mechanism of DHA in pancreatic carcinogenesis based on the recent studies.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2039-2044
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• 2014

This study was conducted in order to obtain a screening and early detection reference for children whose mothers had been diagnosed with cancer. Data for 276 mother-child pairs with malignant tumors were analyzed. The distribution of cancers in affected families was generally similar to that of the general Chinese population, and correspondingly breast cancer was the most common malignancy amongst daughters whose mother had cancer (32.7%). The most prevalent cancer amongst sons with affected mothers was gastric cancer, rather than lung cancer. Daughters were more likely to have the same kind of malignant tumor as their mother (P<0.05), and were more likely to develop breast cancer than any other malignant disease if their mother had a breast tumor (P<0.0001). Likewise, if the mother was diagnosed with breast or gynecological cancer, the daughter was more likely to be diagnosed with breast or gynecological cancer than any other cancer (P<0.01). Daughters and sons developed malignant diseases 11 and 6.5 years earlier than their mothers, respectively (P<0.0001).Women with a mother who suffered cancer should be screened for malignancy from 40 years of age especially for breast, lung, and gynecological cancers. For men with affected mothers, screening should start when they are 45 years old focusing particularly on lung and digestive system cancers.

• Journal of Digestive Cancer Reports
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• v.8 no.1
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• pp.1-50
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• 2020

Although surgery was the standard treatment for early gastrointestinal cancers, endoscopic resection is now a standard treatment for early gastrointestinal cancers without regional lymph node metastasis. High-definition white light endoscopy, chromoendoscopy, and image-enhanced endoscopy such as narrow band imaging are performed to assess the edge and depth of early gastrointestinal cancers for delineation of resection boundaries and prediction of the possibility of lymph node metastasis before the decision of endoscopic resection. Endoscopic mucosal resection and/or endoscopic submucosal dissection can be performed to remove early gastrointestinal cancers completely by en bloc fashion. Histopathological evaluation should be carefully made to investigate the presence of risk factors for lymph node metastasis such as depth of cancer invasion and lymphovascular invasion. Additional treatment such as radical surgery with regional lymphadenectomy should be considered if the endoscopically resected specimen shows risk factors for lymph node metastasis. This is the first Korean clinical practice guideline for endoscopic resection of early gastrointestinal cancer. This guideline was developed by using mainly de novo methods and encompasses endoscopic management of superficial esophageal squamous cell carcinoma, early gastric cancer, and early colorectal cancer. This guideline will be revised as new data on early gastrointestinal cancer are collected.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1313-1320
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• 2014

Introduction: Although most prostate cancers initially respond to castration with luteinizing hormonereleasing analogues or bilateral orchiectomy, progression eventually occurs. Based on the exciting results of several randomized controlled trials (RCTs), it seems that patients with metastatic castration-resistant prostate cancer (mCRPC) might benefit more from treatment withabiraterone. Therefore we conducted a systematic review to evaluate the efficacy and toxicity of abiraterone in the treatment of mCRPC. Methods: Literature was searched from Embase, PubMed, Web of Science, and Cochrane Library up to July, 2013. Quality of the study was evaluated according to the Cochrane's risk of bias of randomized controlled trial (RCT) tool, then the Grading of Recommendations Assessment, Development and Evaluation (GRADE) System was used to rate the level of evidence. Stata 12.0 was used for statistical analysis. Summary data from RCTs comparing abiraterone plus prednisone versus placebo plus prednisone for mCRPC were meta-analyzed. Pooled hazard ratios (HRs) for overall survival (OS), radiographic progression-free survival (RPFS) and time to PSA progression (TTPP); Pooled risk ratios (RR) for PSA response rate, objective response rate and adverse event were calculated. Results: Ten trials were included in the systematic review; Data of 2,283 patients (1,343 abiraterone; 940 placebo) from two phase 3 trials: COU-AA-301 and COU-AA-302 were meta-analyzed. Compared with placebo, abiraterone significantly prolonged OS (HR, 0.74; 95% confidence interval [CI], 0.66 to 0.84), RPFS (HR, 0.59; 95% CI, 0.48 to 0.74) and time to PSA progression (HR, 0.55; 95% CI, 0.43 to 0.70); it also significantly increased PSA response rate (RR, 3.63; 95% CI, 1.72 to 7.65) and objective response rate (RR, 3.05; 95% CI, 1.51 to 6.15). This meta-analysis suggested that the adverse events caused by abiraterone are acceptable and can be controlled. Conclutios: Abiraterone significantly prolonged OS, RPFS and time to progression patients with mCRPC, regardless of prior chemotherapy or whether chemotherapy-na$\ddot{i}$ve, and no unexpected toxicity was evident. Abiraterone can serve as a new standard therapy for mCRPC.