Additional Benefits of Routine Drugs on Gastrointestinal Cancer: Statins, Metformin, and Proton Pump Inhibitors

Potential Chemopreventive Effects of Dietary Combination of Phytochemicals against Cancer Development

Cancer remains a major cause of cancer-related death worldwide. Over 70% of epithelial malignancies are sporadic and are related to lifestyle. Epidemiological studies suggest an inverse correlation between cancer incidence and fruit and vegetable intake. Numerous preclinical studies using in vitro (cell lines) and in vivo animal models of oncogenesis have reported the chemopreventive effects of dietary phytochemical agents through alterations in different biomarkers and signaling pathways. However, there is contrasting evidence from preclinical studies and clinical trials. To date, the most studied compounds include curcumin, resveratrol, isoflavones, green tea extract (epigallocatechin gallate), black raspberry powder (anthocyanins and ellagitannins), bilberry extract (anthocyanins), ginger extract (gingerol derivatives), and pomegranate extract (ellagitannins and ellagic acid). Overall, the clinical evidence of the preventive effects of dietary phytochemicals against cancer development is still weak, and the amount of these phytochemicals needed to exert chemopreventive effects largely exceeds the common dietary doses. Therefore, we propose a combination treatment of natural compounds that are used clinically for another purpose in order to obtain excess inhibitory efficacy via low-dose administration and discuss the possible reasons behind the gap between preclinical research and clinical trials.

Exposure to Commonly Used Drugs and the Risk of Gastric Cancer: An Umbrella Review of Meta-Analyses

Recently, attention has been paid to some medications and gastric cancer (GC) risk. This review aimed to evaluate associations between commonly used drugs and GC risk and to grade evidence from published systematic reviews and meta-analyses. This umbrella review was registered in PROSPERO (CRD42022320276). The systematic reviews and meta-analyses of observational studies were retrieved by searching Embase, PubMed, and Web of Science. The evidence strength of commonly used drugs and GC risk was categorized into four grades: weak, suggestive, highly suggestive, and strong. Of 19 associations between commonly used drugs and GC risk and its subtypes, none was supported by convincing or highly suggestive evidence. The risk of GC related to non-steroidal anti-inflammatory drugs (NSAIDs), non-aspirin NSAIDs, and acid-suppressive drugs, as well as the risk of non-cardia GC related to NSAIDs and aspirin, was supported by suggestive evidence. The results showed that a reduced GC risk was associated with two drug types (NSAIDs and non-aspirin NSAIDs), and an increased GC risk was associated with acid-suppressing drugs at the suggestive evidence level. Moreover, NSAIDs and aspirin reduced non-cardia GC risk as supported by suggestive evidence. However, the evidence supporting statins or metformin in reducing GC risk was weak, and thus future studies are required to clarify these associations.

Chronic metformin intake and gastric cancer: A pooled analysis within the Stomach cancer Pooling (StoP) Project

INTRODUCTION

The association between chronic use of metformin and risk of gastric cancer (GC) has been investigated with contradicting results. We aimed to study the association between chronic use of metformin and GC by using data from the Stomach cancer Pooling (StoP) Project, an epidemiological consortium of case-control studies on GC.

METHODS

Data from three studies of the StoP Project with available information on metformin intake were analyzed. Multivariable logistic regression models were used to estimate study-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between chronic use of metformin and GC risk. Analyses were adjusted for sex, age, socioeconomic status, body mass index, smoking status, alcohol drinking status, and history of diabetes. Study-specific ORs and 95% CIs were then pooled with a random-effects model. The dose-response relationship between the duration of metformin intake and GC was assessed with a one-stage logistic model, and the duration of intake was modelled using second-order fractional polynomials.

RESULTS

The OR of GC in metformin users versus non-users was 1.01 (95% CI=0.61, 1.67). The association between metformin and GC did not change among different strata of study participants' characteristics or when restricting the analyses to those with a history of diabetes. The dose-response analysis showed a slightly reducing trend in the OR of GC and a borderline significant association with increasing duration of metformin intake.

CONCLUSIONS

The results of our study do not clearly support an association between chronic use of metformin and GC, warranting further research.

Nationwide cohort study: cholesterol level is inversely related with the risk of gastric cancer among postmenopausal women

BACKGROUND

Recent studies showed inverse relationship between hypercholesterolemia and the risk of gastric cancer, especially among male. However evidence among female is inconsistent. We aimed to investigate the relationship between cholesterol level and the risk of gastric cancer among female according to menopausal status.

METHODS

We analyzed the data from a population-based prospective cohort of female ≥ 30 years old who underwent cancer screening and general health screening provided by the Korean National Health Insurance Corporation in 2009. Under quartile stratification of the level of cholesterol components, we calculated the hazard ratio (HR) for gastric cancer incidence until 2018 for each level group according to the menopausal status at 2009.

RESULTS

Among total 2,722,614 individuals, 17,649 gastric cancer cases developed after mean 8.26 years of follow-up (premenopausal 3746/1180666; postmenopausal 13,903/1541948). Total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) showed inverse relationship with the risk of gastric cancer among postmenopausal women (adjusted HR (95% confidence interval) for the highest quartile vs. lowest quartile and p-for-trend: 0.88 (0.84-0.92) and < 0.001 for total cholesterol; 0.89 (0.85-0.92) and < 0.001 for HDL-C; 0.92 (0.89-0.97) and 0.001 for LDL-C), whereas none showed statistically significant risk relationship among premenopausal women. Triglyceride was not independently related with gastric cancer risk among both pre- and postmenopausal women.

CONCLUSIONS

Cholesterol levels, including total cholesterol, HDL-C, and LDL-C, are inversely related with the risk of gastric cancer among postmenopausal women, but not among premenopausal women.

Improved prognosis in gastric adenocarcinoma among metformin users in a population-based study

BACKGROUND

Metformin may improve the prognosis in gastric adenocarcinoma, but the existing literature is limited and contradictory.

METHODS

This was a Swedish population-based cohort study of diabetes patients who were diagnosed with gastric adenocarcinoma in 2005-2018 and followed up until December 2019. The data were retrieved from four national health data registries: Prescribed Drug Registry, Cancer Registry, Patient Registry and Cause of Death Registry. Associations between metformin use before the gastric adenocarcinoma diagnosis and the risk of disease-specific and all-cause mortality were assessed using multivariable Cox proportional hazard regression. The hazard ratios (HRs) and 95% confidence intervals (CIs) were adjusted for sex, age, calendar year, comorbidity, use of non-steroidal anti-inflammatory drugs or aspirin, and use of statins.

RESULTS

Compared with non-users, metformin users had a decreased risk of disease-specific mortality (HR 0.79, 95% CI 0.67-0.93) and all-cause mortality (HR 0.78, 95% CI 0.68-0.90). The associations were seemingly stronger among patients of female sex (HR 0.66, 95% CI 0.49-0.89), patients with tumour stage III or IV (HR 0.71, 95% CI 0.58-0.88), and those with the least comorbidity (HR 0.71, 95% CI 0.57-0.89).

CONCLUSIONS

Metformin use may improve survival in gastric adenocarcinoma among diabetes patients.

The Relationship between Diabetes Mellitus and Gastric Cancer and the Potential Benefits of Metformin: An Extensive Review of the Literature

The objective of this review is to summarize the findings of published research that investigated the relationship between diabetes mellitus and gastric cancer (GCa) and the potential benefits of metformin on GCa. Related literature has been extensively reviewed, and findings from studies investigating the relationship between diabetes mellitus and GCa suggest that hyperglycemia, hyperinsulinemia and insulin resistance are closely related to the development of GCa. Although not supported by all, most observational studies suggest an increased risk of GCa in patients with type 2 diabetes mellitus, especially in women and in Asian populations. Incidence of second primary malignancy diagnosed after GCa is significantly higher in diabetes patients. Diabetes patients with GCa may have more complications after gastrectomy or chemotherapy and they may have a poorer prognosis than patients with GCa but without diabetes mellitus. However, glycemic control may improve in the diabetes patients with GCa after receiving gastrectomy, especially after procedures that bypass the duodenum and proximal jejunum, such as Roux-en-Y gastric bypass or Billroth II reconstruction. The potential links between diabetes mellitus and GCa may involve the interactions with shared risk factors (e.g., obesity, hyperglycemia, hyperinsulinemia, insulin resistance, high salt intake, smoking, etc.), Helicobacter pylori (HP) infection, medications (e.g., insulin, metformin, statins, aspirin, proton pump inhibitors, antibiotics, etc.) and comorbidities (e.g., hypertension, dyslipidemia, vascular complications, heart failure, renal failure, etc.). With regards to the potential benefits of metformin on GCa, results of most observational studies suggest a reduced risk of GCa associated with metformin use in patients with T2DM, which can be supported by evidence derived from many in vitro and animal studies. Metformin use may also reduce the risk of HP infection, an important risk factor of GCa. In patients with GCa, metformin users may have improved survival and reduced recurrence. More studies are required to clarify the pathological subtypes/anatomical sites of GCa associated with type 2 diabetes mellitus or prevented by metformin, to confirm whether GCa risk can also be increased in patients with type 1 diabetes mellitus and to explore the possible role of gastric microbiota in the development of GCa.

Effect of frequently prescribed drugs on gastric cancer risk

Gastric cancer is the fifth leading cancer worldwide. Infection with Helicobacter pylori represents the major risk factor, but only a small fraction of infected individuals will develop neoplasia. The progression of advanced gastric lesions to cancer is influenced by characteristics of the bacterial strain, host genetic and environmental factors. Recently, the effect of medications on gastric cancer risk has gained interest, because many commonly prescribed drugs affect gastric homeostasis. While non-steroidal anti-inflammatory drugs (NSAIDs) are a frequent cause of gastric ulcer disease, low-dose aspirin has been propagated for chemoprevention of various tumour entities. Beneficial effects of cyclooxygenase-inhibition for gastric cancer prevention is plausible, but its clinical relevance remains unclear. Furthermore, anti-tumorous effects have been postulated for statins and metformin. On the contrary, proton pump inhibitors (PPIs), which are commonly used for prevention of gastric ulcers and bleeding, have been associated with an increased gastric cancer risk in large observational studies. Most of these observations still require confirmation in prospective controlled trials. NSAIDs, statins and metformin have also been investigated as concomitant cancer treatment, but studies did not show convincing results to date. Here, we review the available evidence and possible mechanisms for the role of PPIs, NSAIDs, statins and metformin in gastric carcinogenesis, and discuss possible implications for clinical practice.

Current Status of Chemoprevention in Barrett's Esophagus

Candidates for chemoprevention in Barrett's esophagus have long been suggested and there has been observational data to support many drugs, including statins, hormone replacement therapy, metformin, proton pump inhibitor therapy, and aspirin. Proton pump inhibitor therapy and aspirin are the most promising agents. Data suggest that aspirin and proton pump inhibitor therapy can decrease the risk of neoplastic progression in Barrett's esophagus. Further, the combination of aspirin and proton pump inhibitor therapy decrease all-cause mortality by approximately 33%. Future guideline groups need to evaluate the evidence rigorously, but the combination of proton pump inhibitor therapy and aspirin is promising.

Association of Common Use Pharmaceuticals in Reducing Risk of Esophageal Adenocarcinoma: A SEER-Medicare Analysis

Barrett's esophagus (BE), a recognized risk factor for esophageal adenocarcinoma (EAC), is routinely managed with proton pump inhibitors (PPIs) when symptomatic. Several lines of evidence suggest that PPIs may prevent malignant transformation. Chronic use of other common drugs, namely, statins nonsteroidal anti-inflammatory drugs (NSAIDs) and metformin, may also interfere with BE carcinogenesis, but confirmatory evidence is lacking. We identified 1,943 EAC cases and 19,430 controls (matched 10:1) between 2007 and 2013 that met our specified inclusion criteria in the SEER-Medicare database. Conditional logistic regression was used to generate odds ratios (OR) and 95% confidence intervals (95% CI). Wald χ² tests were used to assess significance of covariates. Compared with controls, EAC cases had a higher prevalence of BE (26.2%). Use of PPIs, NSAIDs, statins, or metformin reduced the odds of EAC (PPIs: 0.10; 95% CI, 0.09-0.12; NSAIDs: 0.62; 95% CI, 0.51-0.74; statins: 0.15; 95% CI, 0.13-0.17; metformin: 0.76; 95% CI, 0.62-0.93). When stratified by BE, these associations persisted, though no association was found between NSAID use and EAC risk for participants with BE. Dual use of PPIs with NSAIDs or statins, and NSAID, statin, or metformin use alone also showed significant EAC risk reduction among all participants and those without BE. Use of PPIs alone and with NSAIDs, statins, or metformin was associated with reduced risk of EAC; however, a history of BE may diminish drug efficacy. These results indicate that common pharmacologic agents alone or in combination may decrease EAC development.Prevention Relevance: The use of common drugs, such as proton pump inhibitors, statins, non-steroidal anti-inflammatory drugs, or metformin, may reduce one's risk of developing esophageal adenocarcinoma. These results suggest that repurposing agents often used for common chronic conditions may be a new strategy for cancer prevention efforts.

Chemoprevention of esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) is a major cause of cancer-related death, particularly in Western populations, and is rapidly rising in Asian populations at this time. Virtually all EACs develop from the precursor lesion Barrett's esophagus (BE), which is the most significant risk factor for EAC. However, the rates of progression from BE to EAC are low and patients with BE are asymptomatic. Thus, any strategy for EAC prevention must carry a low risk of harm in order to be clinically useful. Since current EAC-screening and BE-surveillance methods carry some procedural risk and are burdensome, there is an opportunity for chemoprevention, i.e. medications or dietary factors that may prevent BE from progressing to EAC. A variety of candidate chemoprevention therapies have been assessed to date. Proton-pump inhibitors (PPIs) are the best studied and have modest EAC-chemoprevention efficacy in BE patients, with a recent randomized trial showing that high-dose PPI may be more effective than low-dose PPI. Aspirin and other non-steroidal anti-inflammatory drugs have moderate quality observational and randomized-trial evidence for preventing progression of BE to EAC, but their risks for harm have precluded their routine clinical use. Other therapies (statins, metformin, female sex hormones) generally do not have strong evidence to support their use in EAC chemoprevention. Although progress has been made in this field, there is still a need for more effective and safe chemoprevention therapies for EAC.

Statin Use Improves Overall Survival of Patients with Gastric Cancer after Surgery and Adjuvant Chemotherapy in Taiwan: A Nationwide Matched Cohort Study

Background: Numerous studies have revealed that statins have antitumor effects in vivo and in vitro. However, few studies have explored the relationship between statin use and the mortality of gastric cancer (GC) patients after treatments. This study examines the relationship between statin use and the overall survival (OS) of GC patients after surgery and adjuvant chemotherapy, using data from the nationwide cohort database of Taiwan. Methods: All patients newly diagnosed with GC from 1999 to 2008 in Taiwan were identified from the Registry of Catastrophic Illness Patients Database. Through propensity score matching, statin users were matched to statin non-users at a 1:4 ratio. The relationship between statin use and the OS of patients with GC was estimated through Cox regression models. Results: The study cohort included 1835 patients with GC who had received therapies during the study period. The death numbers among statin users (defined as those who used more than 28 cumulative defined daily doses (cDDDs)) and statin non-users were 138 and 895, respectively. A dose–response association was noted between statin use and the OS of patients with GC after treatments. The adjusted hazard ratios were 0.62 (95% confidence intervals (CI), 0.50–0.78) and 0.34 (95% CI, 0.26–0.45) for statin users administered 28–167 cDDDs and >168 cDDDs, respectively, compared with no statin use (<28 cDDDs). Conclusions: This study highlights that statin use may dose-dependently improve the OS of patients with GC after surgery and adjuvant chemotherapy in Taiwan. Additional studies are required to confirm the efficacy and safety of statin use.

Impact of metformin on survival outcome of esophageal squamous cell carcinomas patients undergoing surgical resection: a multicenter retrospective study

Background

Diabetes mellitus is a recognized risk factor for esophageal squamous cell carcinomas (ESCC), and metformin is a recognized protective factor for some gastrointestinal tumors. But knowledge is limited regarding the effect of metformin on survival outcome of ESCC patients with type 2 diabetes mellitus (T2DM). We assessed the impact of post-diagnosis metformin use on overall survival (OS) and disease-free survival (DFS) in ESCC with T2DM undergoing surgical resection.

Methods

A retrospective analysis was performed on 3,523 patients with ESCC who met the study conditions after surgical resection. Log-rank and Cox regression models were used to evaluate the relationship between metformin and T2DM and ESCC survival rate, and adjusted according to age, gender, BMI, smoking, drinking and staging, et al.

Results

Among included ESCC patients, 619 were associated with type 2 diabetes, while the remaining 2,904 were not associated with type 2 diabetes. The 5-year OS (28.43%) of patients with T2DM was significantly lower than that of patients without T2DM (32.75%), P=0.037. DFS in 5 years were 27.30% (with T2DM) and 31.75% (without T2DM) (P=0.030), respectively. Compared with patients without T2DM, patients with T2DM presented worse OS [adjusted risk ratio (HR_adj) =1.19] and DFS (HRadj =1.17; P<0.001). Among the 619 patients with type 2 diabetes, 485 were treated with metformin and 134 were not treated with metformin. Patients treated with metformin had significantly improved OS [adjusted risk ratio (HR_adj) =0.89; P=0.031) and DFS (HR_adj =0.90; P=0.013).

Conclusions

T2DM was again associated with poorer survival in ESCC patients, and metformin may improve the prognosis of these patients.

Association Between Metformin Use and Risk of Esophageal Squamous Cell Carcinoma in a Population-Based Cohort Study

OBJECTIVES

Esophageal cancer is a highly fatal malignant neoplasm, with 2 etiologically different histological types. A large prospective study is expected to elucidate the specific risk of the 90% subtype of esophageal cancer, esophageal squamous cell carcinoma (ESCC), with metformin therapy. This study aims to determine the association between metformin use and incident ESCC risk.

METHODS

This was a nationwide population-based prospective cohort study conducted in Sweden in 2005-2015. Among 8.4 million participants identified in the cohort, 411,603 (5%) were metformin users. The users were compared with 10 times as many frequency-matched nonusers of metformin (n = 4,116,030) by age and sex. Metformin use was treated as a time-varying variate, and multivariable cause-specific proportional hazards model was used to calculate hazard ratios (HR) with 95% confidence intervals (CI) for ESCC, adjusted for age, sex, calendar year, residence area, tobacco smoking, alcohol overconsumption, and use of nonsteroidal anti-inflammatory drugs or statins.

RESULTS

The incidence rates of ESCC were 3.5 per 100,000 person-years among the metformin users and 5.3 per 100,000 person-years in the nonusers. Metformin users overall were at a decreased risk of ESCC compared with nonusers (HR 0.68, 95% CI 0.54-0.85). The decrease in risk was more pronounced in new metformin users (HR 0.44, 95% CI 0.28-0.64) and participants aged 60-69 years (HR 0.45, 95% CI 0.31-0.66).

DISCUSSION

Metformin use decreases the risk of developing ESCC.

Metformin use and risk of gastric adenocarcinoma in a Swedish population-based cohort study

Background

Whether or not the use of metformin decreases the risk of gastric adenocarcinoma is unclear.

Methods

This was a population-based cohort study in 2005–2015. Associations between metformin use and gastric non-cardia and cardia adenocarcinomas were examined within two cohorts; a diabetes cohort of participants using anti-diabetes medications, and a matched cohort of common-medication users, where metformin non-users were frequency matched (10:1) with metformin users for sex and age. Multivariable Cox proportional hazard regression analyses provided hazard ratios (HR) and 95% confidence intervals (CI), adjusting for sex, age, calendar year, comorbidity, Helicobacter pylori eradication treatment, use of non-steroidal anti-inflammatory drugs or aspirin and use of statins.

Results

During the follow-up for a median of 5.8 years, 892 (0.1%) participants in the diabetes cohort and 6395 (0.1%) participants in the matched cohort of common-medication users developed gastric adenocarcinoma. Metformin users had no significantly decreased risk of gastric non-cardia adenocarcinoma (diabetes cohort: HR 0.93, 95% CI 0.78–1.12; matched cohort: HR 1.30, 95% CI 1.18–1.42) or cardia adenocarcinoma (diabetes cohort: HR 1.49, 95% CI 1.09–2.02; matched cohort: HR 1.58, 95% CI 1.38–1.81) compared with non-users in both cohorts.

Conclusions

This cohort study with <10 years of follow-up suggests metformin use may not prevent gastric adenocarcinoma.

Lifestyle and dietary environmental factors in colorectal cancer susceptibility

Colorectal cancer (CRC) incidence changes with time and by variations in diet and lifestyle, as evidenced historically by migrant studies and recently by extensive epidemiologic evidence. The worldwide heterogeneity in CRC incidence is strongly suggestive of etiological involvement of environmental exposures, particularly lifestyle and diet. It is established that physical inactivity, obesity and some dietary factors (red/processed meats, alcohol) are positively associated with CRC, while healthy lifestyle habits show inverse associations. Mechanistic evidence shows that lifestyle and dietary components that contribute to energy excess are linked with increased CRC via metabolic dysfunction, inflammation, oxidative stress, bacterial dysbiosis and breakdown of gut barrier integrity while the reverse is apparent for components associated with decreased risk. This chapter will review the available evidence on lifestyle and dietary factors in CRC etiology and their underlying mechanisms in CRC development. This short review will also touch upon available information on potential gene-environment interactions, molecular sub-types of CRC and anatomical sub-sites within the colorectum.

Statin use and survival in patients with gastric cancer in two independent population-based cohorts

PURPOSE

Preclinical studies show statins inhibit pathways involved in gastric cancer progression, with observational studies demonstrating reduced gastric cancer risk in statin users. However, few studies have investigated statin use and survival in gastric cancer. We investigated statin use and survival in two large population-based gastric cancer cohorts.

METHODS

Patients diagnosed with gastric cancer from 1998 to 2012 were identified from English and Scottish cancer registries. Statin prescriptions were identified from linkages to the UK Clinical Practice Research Datalink in England and the Prescribing Information System in Scotland, and deaths identified from national mortality records. Time-dependent Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CIs) for cancer-specific mortality by statin use in multivariate analysis. Meta-analysis techniques pooled results across the cohorts.

RESULTS

The combined cohorts contained 3833 patients with gastric cancer and 2392 cancer-specific deaths. Statin use after diagnosis was associated with reduced cancer-specific mortality (adjusted HR 0.83; 95% CI, 0.74-0.92). HRs for less than 1 year and over 1 year of statin use were similar (adjusted HR 0.83; 95% CI, 0.73-0.94 and adjusted HR 0.83; 95% CI, 0.64-1.01, respectively). Statin use prior to diagnosis was also associated with reduced cancer-specific mortality (adjusted HR 0.91; 95% CI, 0.84-0.98).

CONCLUSIONS

In two independent UK cohorts, there was some evidence that statin use was associated with reduced cancer-specific mortality. However, these associations were weak in magnitude and did not follow a clear dose response, and we cannot rule out confounding by stage.

Chronic Statin Therapy and Histologic Gastric Changes

Background: The additional benefits of certain frequently used chronic drugs such as statins or aspirin are investigated for their possible effect of influencing various types of cancer, including gastric cancer. The possible role of statins in the occurrence of pre-neoplastic gastric lesions has not been investigated.

Aim: The study aims to determine the influence of chronic statin therapy on premalignant gastric lesions (glandular atrophy, intestinal metaplasia and dysplasia), adjusted with the most important aggressive environmental factors of the gastric mucosa (Helicobacter pylori [H. pylori] infection, low-dose aspirin [acetylsalicylic acid, ASA], biliary reflux, smoking, alcohol consumption).

Method: The study included 566 patients with cardiovascular diseases who underwent an upper endoscopy: 222 patients with chronic statin therapy (atorvastatin 20–80 mg/day or rosuvastatin 5–20 mg/day for at least 6 months) and 344 patients without statin intake. A complete set of biopsies from the gastric antrum and corpus were routinely processed and examined, and demographical, clinical, and pathological variables were recorded.

Results: Active H. pylori infection in gastric biopsies (p = 0.45), biliary reflux (p = 0.74), alcohol consumption (p = 0.43), or prior ulcer disease (p = 0.07; OR: 0.59; 95% CI: 0.33–1.04) were not associated with an increased risk for premalignant lesions, neither in the statin, nor the no-statin group. Smoking was associated with premalignant lesions in both groups (p = 0.01; OR: 2.24; 95% CI: 1.12–4.47; and p = 0.04; OR: 1.72; 95% CI: 1.01–2.94, respectively), while chronic use of ASA had no influence (p = 0.24, respective p = 0.35). In multivariate regression models, chronic treatment with statins had a protective effect (p = 0.006; OR: 0.59; 95% CI: 0.4–0.8), while smoking (p = 0.01; OR: 1.99; 95% CI: 1.17–3.39) and age >50 years (p <0.01, OR: 3.09; 95% CI: 1.84–5.21) were predictors for pre-neoplastic lesions. H. pylori infection, gender, alcohol consumption, biliary reflux, or prior ulcer disease were not associated with premalignant lesions (p >0.05). Conclusions: In the studied population, chronic statin treatment seems to be associated with a decreased risk for premalignant gastric lesions, while age over 50 years and smoking, regardless of gender or ASA consumption, remain the most important risk factors for premalignant gastric lesions.

Metformin transporter pharmacogenomics: insights into drug disposition-where are we now?

INTRODUCTION

Metformin is recommended as first-line treatment for type 2 diabetes (T2D) by all major diabetes guidelines. With appropriate usage it is safe and effective overall, but its efficacy and tolerability show considerable variation between individuals. It is a substrate for several drug transporters and polymorphisms in these transporter genes have shown effects on metformin pharmacokinetics and pharmacodynamics. Areas covered: This article provides a review of the current status of the influence of transporter pharmacogenomics on metformin efficacy and tolerability. The transporter variants identified to have an important influence on the absorption, distribution, and elimination of metformin, particularly those in organic cation transporter 1 (OCT1, gene SLC22A1), are reviewed. Expert opinion: Candidate gene studies have shown that genetic variations in SLC22A1 and other drug transporters influence the pharmacokinetics, glycemic responses, and gastrointestinal intolerance to metformin, although results are somewhat discordant. Conversely, genome-wide association studies of metformin response have identified signals in the pharmacodynamic pathways rather than the transporters involved in metformin disposition. Currently, pharmacogenomic testing to predict metformin response and tolerability may not have a clinical role, but with additional data from larger studies and availability of safe and effective alternative antidiabetic agents, this is likely to change.

Potential impact of Helicobacter pylori-related metabolic syndrome on upper and lower gastrointestinal tract oncogenesis

Both Helicobacter pylori infection and metabolic syndrome present significant global public health burdens. Metabolic syndrome is closely related to insulin resistance, the major underlying mechanism responsible for metabolic abnormalities, and Helicobacter pylori infection has been proposed to be a contributing factor. There is growing evidence for a potential association between Helicobacter pylori infection and insulin resistance, metabolic syndrome and related morbidity, including abdominal obesity, type 2 diabetes mellitus, dyslipidemia, hypertension, all of which increase mortality related to cardio-cerebrovascular disease, neurodegenerative disorders, nonalcoholic fatty liver disease and malignancies. More specifically, insulin resistance, metabolic syndrome and hyperinsulinemia have been associated with upper and lower gastrointestinal tract oncogenesis. Apart from cardio-cerebrovascular, degenerative diseases and nonalcoholic fatty liver disease, a number of studies claim that Helicobacter pylori infection is implicated in metabolic syndrome-related Barrett's esophagus and esophageal adenocarcinoma development, gastric and duodenal ulcers and gastric oncogenesis as well as lower gastrointestinal tract oncogenesis. This review summarizes evidence on the potential impact of Helicobacter pylori-related metabolic syndrome on gastroesophageal reflux disease-Barrett's esophagus-esophageal adenocarcinoma, gastric atrophy-intestinal metaplasia-dysplasia-gastric cancer and colorectal adenoma-dysplasia-colorectal cancer sequences. Helicobacter pylori eradication might inhibit these oncogenic processes, and thus further studies are warranted.

Introduction: Esophageal Adenocarcinoma: Updates of Current Status

Esophageal and esophagogastric adenocarcinoma is highly prevalent in the Western populations and is a major cause of cancer-related morbidity and mortality worldwide. The incidence of esophageal adenocarcinoma is rapidly rising in the Western populations. The major predisposing diseases and pathogenesis (gastro-esophageal reflux disease, Barrett esophagus, and dysplasia) of the cancer are well known. There is an urgent need for works of the multidisciplinary teams (clinical, pathological, the molecular biology and translational research) for improved outcomes of patients with this cancer.