The association between NSAID use and colorectal cancer mortality: results from the women's health initiative

Meta-analysis of aspirin-guided therapy of colorectal cancer

Abstract

Purpose colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. Some evidence has shown that aspirin can reduce the morbidity and mortality of CRC. The aim of this meta-analysis was to compare standard care of patients with CRC and standard care with the addition of aspirin in terms of the survival benefit.

Methods

The systematic search was conducted by two independent reviewers in the databases PubMed and Web of Science. Survival data were extracted from studies published before July 2019. We searched for randomised controlled trials, cohort studies and case-control studies.

Results

We included 27 studies in our meta-analysis. There was a sample size of 237,245 patients overall. Aspirin use after diagnosis was associated with an improvement in CRC-specific survival with a hazard ratio (HR) for cancer-related death of 0.74 (95% CI: 0.62–0.89). Our analysis of overall survival data revealed reduced mortality with an HR of 0.82 (95% CI: 0.74–0.90). Patients with the phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutation profited from postdiagnosis aspirin use (HR = 0.74, 95% CI: 0.56–0.97). For a high expression of prostaglandin-endoperoxide synthase 2 (PTGS2) = COX-2, we found an HR of 0.65 (95% CI: 0.52–0.82).

Conclusion

Aspirin can improve the outcome of patients with CRC. PIK3CA mutation status and high expression of PTGS2 are associated with longer survival. However, randomised controlled trials are needed to investigate postdiagnosis aspirin use in CRC patients taking into account cancer stage and gene expression.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-022-03942-1.

Challenges of improving treatment outcomes for colorectal and anal cancers in Japan: the Colorectal Cancer Study Group (CCSG) of the Japan Clinical Oncology Group (JCOG)

Colorectal cancer is a major public health concern in Japan. While early-stage colorectal adenocarcinoma treatment entails radical resection of the primary tumor, the importance of perioperative treatment is growing as physicians seek to further improve treatment outcomes. For anal squamous cell carcinoma, definitive chemoradiotherapy is superior to radical surgery in terms of improved patient quality of life. The Colorectal Cancer Study Group of the Japanese Clinical Oncology Group was established in 2001 and has worked to provide answers to common clinical questions and improve treatment outcomes for colorectal and anal cancers through 15 large-scale prospective clinical trials. Here, we discuss the current state of perioperative treatment for early-stage colon, rectal and anal cancers in Japan and approaches taken by the Colorectal Cancer Study Group/the Japanese Clinical Oncology Group to improve treatment outcomes for these cancers.

Role of Anti-inflammatory Drugs in the Colorectal Cancer

Objective: The objective of this review was to systematically review and synthesize evidence regarding benefits of using nonsteroidal anti-inflammatory drugs (NSAIDs) for the treatment of colorectal cancer (CRC). Data Sources: The data sources were MEDLINE, PubMed, NEJM, Google Scholar, and Google searches of references from relevant and eligible trials. Review Methods: We screened abstracts and full-text articles of identified references for eligibility and reviewed randomized controlled trials, cohort studies, and meta-analysis for evidence on benefits of using NSAIDs in CRC treatments. For all extracted data, completeness and relevance were checked. Results: The risk of any adenoma among frequent NSAID users was 26.8% vs 39.9% among placebo subjects who later used NSAIDs sporadically (adjusted relative risk = 0.62, 95% confidence interval [CI] = 0.39-0.98; P trend with NSAID use frequency = .03). Long-term use of aspirin reduces the risk of CRC. Aspirin also reduces the incidence of colon adenomas and mortality, especially when used for >10 years. Rofecoxib is associated with the reduction of CRC; however, it was associated with cardiovascular risk (with an overall unadjusted relative risk of 1.50 [95% CI = 0.76-2.94; P = .24]). Adenoma Prevention with Celecoxib trial shows that, for patients of all genotypes, the estimated cumulative incidence of one or more adenomas by year 3 was 59.8% for those randomized to placebo as compared with 43.3% for those randomized to low-dose (200 mg, twice daily) celecoxib (relative risk [RR] = 0.68; 95% CI = 0.59-0.79; P < .001) and 36.8% for those randomized to high-dose (400 mg, twice daily) celecoxib and 60.7% in placebo group (RR = 0.54; 95% CI = 0.46-0.64; P < .001). Conclusions: The use of COX-2 inhibitors both prior to and after diagnosis of CRC seemed to be mildly associated with the reduction in mortality of patients with CRC. Some literatures state that COX-2 inhibitors might play a synergistic role in adjuvant chemotherapy of FOLFOX regimen. Celecoxib was found to increase the radiosensitization of colon cancer cells.

Prediagnostic use of low-dose aspirin and risk of incident metastasis and all-cause mortality among patients with colorectal cancer

AIMS

Previous studies suggest that the use of low-dose aspirin before a colorectal cancer (CRC) diagnosis may be associated with a decreased risk of CRC progression. Data supporting this association, however, have been inconsistent. We evaluate whether the use of prediagnostic low-dose aspirin is associated with a lower risk of metastases and all-cause mortality in CRC patients.

METHODS

Using a large Italian population-based primary care database, we identified a cohort of 7478 patients newly diagnosed with nonmetastatic CRC between 2000 and 2013. Use of prediagnostic low-dose aspirin was compared with no use of low-dose aspirin. Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of incident metastasis and of all-cause mortality associated with prediagnostic low-dose aspirin use, both overall and by duration of use.

RESULTS

There were 314 incident metastatic events and 2189 deaths during a mean follow-up time of 4.4 and 4.7 years, respectively. Overall prediagnostic use of low-dose aspirin was not associated with a decreased risk of incident metastasis (HR 0.88; 95% CI 0.63-1.22) or all-cause mortality (HR 1.09; 95% CI 0.96-1.22) in CRC patients. Cumulative duration of aspirin use was not associated with a decreased risk of incident metastasis (P-trend = .22) or all-cause mortality (P-trend = .38). These findings remained consistent in sensitivity analyses.

CONCLUSION

In this real-world, population-based study, the prediagnostic use of low-dose aspirin was not associated with a decreased risk of incident metastasis or all-cause mortality in CRC patients.

Efficacy of aspirin for stage III colorectal cancer: a randomized double-blind placebo-controlled trial (JCOG1503C, EPISODE-III trial)

Adjuvant chemotherapy is the current standard treatment for stage III colorectal cancer after curative resection. However, the prognosis of stage III colorectal cancer is still poor even after curative resection and adjuvant chemotherapy. Several observational studies suggested that the anti-tumor effect of aspirin. Therefore, we planned a randomized double-blind placebo-controlled phase III trial, which commenced in Japan in March 2018, to confirm the superiority of aspirin over placebo added to adjuvant chemotherapy in terms of disease-free survival (DFS) for stage III colorectal cancer patients after curative resection. A total of 880 patients will be accrued from 20 Japanese institutions within 3 years. The primary endpoint is DFS and the secondary endpoints are overall survival, relapse-free survival, relative dose intensity, adverse events, and serious adverse events. This trial has been registered at Japan Registry of Clinical Trials as jRCTs031180009 (https://jrct.niph.go.jp/detail/589).

Post-cancer diagnosis dietary inflammatory potential is associated with survival among women diagnosed with colorectal cancer in the Women's Health Initiative

PURPOSE

Dietary factors may influence colorectal cancer (CRC) survival through effects on inflammation. We examined the association between post-CRC diagnosis inflammatory potential of diet and all-cause and cancer-specific mortality in the Women's Health Initiative.

METHODS

The study included 463 postmenopausal women who developed CRC during follow-up and completed a food frequency questionnaire (FFQ), on average 1.7 years after diagnosis. Women were followed from CRC diagnosis until death, censoring, or the end of follow-up in October 2014. Energy-adjusted dietary inflammatory index (E-DII)^® scores were calculated from the FFQ and dietary supplement inventory. Cox proportional hazards models were fitted to estimate multivariable-adjusted HRs and 95% confidence intervals (CIs) for all-cause, total cancer, and CRC-specific mortality with the most pro-inflammatory E-DII scores (tertile 3) as referent.

RESULTS

After a median 11.6 years of follow-up, 162 deaths occurred, including 77 from CRC. Lowest tertile (i.e., most anti-inflammatory) E-DII scores from diet plus supplements were associated with significantly lower all-cause mortality (HR_T1vsT3 = 0.49; 95% CI 0.31-0.79) compared to the most pro-inflammatory E-DII tertile. Modest associations with total cancer mortality or CRC-specific mortality were observed, though 95% CIs included 1.

CONCLUSIONS

Consuming a dietary pattern and supplements with more anti-inflammatory potential after CRC diagnosis may improve overall survival among postmenopausal women.

Effects of consumption of whole grape powder on basal NF-κB signaling and inflammatory cytokine secretion in a mouse model of inflammation

Dietary consumption of polyphenol-rich fruits, such as grapes, may reduce inflammation and potentially prevent diseases linked to inflammation. Here, we used a genetically engineered murine model to measure Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) activity and pro-inflammatory cytokine secretion to test the hypothesis that oral consumption of whole grape formulation reduces inflammatory signaling in the body. NF-κB luciferase reporter mice were divided into two groups, one which was fed an experimental diet formulated with 4% (w/w) whole grape powder (WGP) or another which was fed a control diet formulated with 3.6% glucose/fructose (w/w) combination. Simulated inflammation was induced in the mice by intraperitoneal injection of lipopolysaccharide (LPS). In vivo imaging was used to determine the effect of each diet on NF-κB activity. We found that there were no significant differences in weight gain between the WGP and control diet groups. However, there was a statistically significant (p<0.0001) difference in the progression of basal levels of NF-κB signaling between mice fed on control or WGP diet. There were no significant differences in NF-κB reporter indices between WGP- and control-diet groups after either acute or repeated inflammatory challenge. However, terminal blood collection revealed significantly (p<0.01) lower serum concentrations of the inflammatory cytokines Interleukin-6 (IL-6) and Tumor Necrosis Factor alpha (TNFα) only among WGP diet mice subjected to acute inflammatory challenge. Overall, these data suggest that while diets supplemented with WGP may suppress steady-state low levels of inflammatory signaling, such a supplementation may not alleviate exogenously induced massive NF-κB activation.

Influence of NSAID Use Among Colorectal Cancer Survivors on Cancer Outcomes

PURPOSE

Colorectal cancer (CRC) is the third most common cancer diagnosed in men and women in the United States. Given the availability of effective screening, most tumors are found early enough to offer patients substantial long-term survival. Thus there is a resulting significant population of CRC survivors for whom modifiable risk factors for recurrence and survival would be of interest.

METHODS

We conducted a population-based retrospective cohort study among patients enrolled in 2 large Midwestern health plans for which claims data, including pharmacy fill data, and medical record data were available. Men and women who were 40 years of age or older at the time of CRC diagnosis with disease less than stage IV and no history of Crohn disease, ulcerative colitis, and irritable bowel syndrome were included. CRC cases diagnosed between January 1, 1990 and December 31, 2000 were included if they met the inclusion criteria. Adjusted Cox proportional hazard models were used with exposure modeled as a time-dependent covariate. We assessed progression-free survival, defined as an aggressive polyp or invasive disease, and overall survival.

RESULTS

After adjustment for age at diagnosis, sex, race, body mass index, stage, side of initial tumor, and tumor histology, we found that current users of nonsteroidal anti-inflammatory drugs had a 3-fold decreased risk of recurrence and a >7-fold decreased risk of death. Our results are statistically significant with P-values <0.05.

CONCLUSIONS

Our results suggest that current use of nonsteroidal anti-inflammatory drugs provides significant improvements in CRC outcomes.

DNA Damage in Healthy Individuals and Respiratory Patients after Treating Whole Blood In vitro with the Bulk and Nano Forms of NSAIDs

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit COX enzyme activity which affects the inflammatory response. Inflammation is associated with increasing cancer incidence. Pre-clinical and clinical studies have shown that NSAID treatment could cause an anti-tumor effect in cancers. In the present study, blood was taken from healthy individuals (n = 17) and patients with respiratory diseases or lung cancer (n = 36). White blood cells (WBC) were treated with either a micro-suspension, i.e., bulk (B) or nano-suspension (N) of aspirin (ASP) or ibuprofen (IBU) up to 500 μg/ml in the comet assay and up to 125 μg/ml in the micronucleus assay. In this study results were compared against untreated lymphocytes and their corresponding treated groups. The results showed, that NSAIDs in their nano form significantly reduced the DNA damage in WBCs from lung cancer patients in bulk and nano compared to untreated lymphocytes. Also, there was a decrease in the level of DNA damage in the comet assay after treating WBCs from healthy individuals, asthma and COPD groups with aspirin N (ASP N) but not with IBU N. In addition, the number of micronuclei decreased after treatment with NSAIDs in their nano form (ASP N and IBU N) in the healthy as well as in the lung cancer group. However, this was not the case for micronucleus frequency in asthma and COPD patients. These data show that lymphocytes from different groups respond differently to treatment with ASP and IBU as measured by comet assay and micronucleus assay, and that the size of the suspended particles of the drugs affects responses.

Patterns of change over time and history of the inflammatory potential of diet and risk of breast cancer among postmenopausal women

We utilized the dietary inflammatory index (DII) to investigate associations between patterns of change in, and history of the inflammatory potential of diet and risk of breast cancer in the Women's Health Initiative (WHI). We included 70,998 postmenopausal women aged 50-79 years recruited from 1993 to 1998 into the WHI Observational Study and Dietary Modification trial control group and followed through August 29, 2014. We utilized data from food frequency questionnaires administered at baseline and Year 3, to calculate average DII scores, patterns of change in DII, and used these measures in multivariable-adjusted Cox regression models to estimate hazards ratios (HR) and 95 % confidence intervals (CI) for incident invasive breast cancer and its subtypes. After 1,093,947 person-years of follow-up, 3471 cases of invasive breast cancer were identified. There was no substantial association between average DII scores or patterns of change in DII and risk of overall invasive breast cancer (HR, 1.03; 95 % CI, 0.90, 1.17; P-trend = 0.79; comparing extreme average DII quintiles). However, there was a significant nonlinear association between average DII scores and the ER-, PR-, HER2+, subtype (HR, 2.37; 95 % CI, 1.08, 5.20; P-trend = 0.18; comparing extreme quintiles). For patterns of change in DII, the age-adjusted association with ER-, PR-, HER2+ subtype comparing women in the proinflammatory stable to those in the anti-inflammatory stable categories (HR, 1.82; 95 % CI, 1.06, 3.13) persisted in the multivariable-adjusted model but was less precise (HR, 1.85; 95 % CI, 0.96, 3.55; P = 0.06). Dietary inflammatory potential may differentially influence the development of specific breast cancer phenotypes.

Association between dietary inflammatory potential and breast cancer incidence and death: results from the Women's Health Initiative

BACKGROUND

Diet modulates inflammation and inflammatory markers have been associated with cancer outcomes. In the Women's Health Initiative, we investigated associations between a dietary inflammatory index (DII) and invasive breast cancer incidence and death.

METHODS

The DII was calculated from a baseline food frequency questionnaire in 122 788 postmenopausal women, enrolled from 1993 to 1998 with no prior cancer, and followed until 29 August 2014. With median follow-up of 16.02 years, there were 7495 breast cancer cases and 667 breast cancer deaths. We used Cox regression to estimate multivariable-adjusted hazards ratios (HRs) and 95% confidence intervals (95% CIs) by DII quintiles (Q) for incidence of overall breast cancer, breast cancer subtypes, and deaths from breast cancer. The lowest quintile (representing the most anti-inflammatory diet) was the reference.

RESULTS

The DII was not associated with incidence of overall breast cancer (HRQ5vsQ1, 0.99; 95% CI, 0.91-1.07; Ptrend=0.83 for overall breast cancer). In a full cohort analysis, a higher risk of death from breast cancer was associated with consumption of more pro-inflammatory diets at baseline, after controlling for multiple potential confounders (HRQ5vsQ1, 1.33; 95% CI, 1.01-1.76; Ptrend=0.03).

CONCLUSIONS

Future studies are needed to examine the inflammatory potential of post-diagnosis diet given the suggestion from the current study that dietary inflammatory potential before diagnosis is related to breast cancer death.

Esophageal Adenocarcinoma: The Influence of Medications Used to Treat Comorbidities on Cancer Prognosis

Esophageal adenocarcinoma has undergone a continuous rise in incidence since the early 1970s and is the fastest rising cancer among white men in the United States. Epidemiologic studies have demonstrated that medications commonly used to treat multiple chronic conditions (for example, aspirin, non-aspirin nonsteroidal anti-inflammatory drugs, and statins) as well as powerful acid suppressants such as proton pump inhibitors are associated with a reduced risk of esophageal adenocarcinoma. The chemopreventive potential of these classes of medications appears to be especially applicable to persons with Barrett's esophagus, the only known premalignant condition for esophageal adenocarcinoma. However, it is not known whether these medications also influence cancer recurrence and cancer-specific mortality in persons diagnosed with esophageal adenocarcinoma. This is an important question because most patients with esophageal adenocarcinoma have 1 or more comorbid conditions at the time of their cancer diagnosis and are receiving medication to treat these conditions. This article summarizes the evidence on the associations between 4 commonly used classes of medications and (1) risk of developing esophageal adenocarcinoma and Barrett's esophagus and (2) risk of cancer recurrence and cancer-specific mortality in patients with esophageal adenocarcinoma.

Construct validation of the dietary inflammatory index among postmenopausal women

PURPOSE

Many dietary factors have either proinflammatory or anti-inflammatory properties. We previously developed a dietary inflammatory index (DII) to assess the inflammatory potential of diet. In this study, we conducted a construct validation of the DII based on data from a food frequency questionnaire and three inflammatory biomarkers in a subsample of 2567 postmenopausal women in the Women's Health Initiative Observational Study.

METHODS

We used multiple linear and logistic regression models, controlling for potential confounders, to test whether baseline DII predicted concentrations of interleukin-6, high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor alpha receptor 2, or an overall biomarker score combining all three inflammatory biomarkers.

RESULTS

The DII was associated with the four biomarkers with beta estimates (95% confidence interval) comparing the highest with lowest DII quintiles as follows: interleukin-6: 1.26 (1.15-1.38), Ptrend < .0001; tumor necrosis factor alpha receptor 2: 81.43 (19.15-143.71), Ptrend = .004; dichotomized hs-CRP (odds ratio for higher vs. lower hs-CRP): 1.30 (0.97-1.67), Ptrend = .34; and the combined inflammatory biomarker score: 0.26 (0.12-0.40), Ptrend = .0001.

CONCLUSIONS

The DII was significantly associated with inflammatory biomarkers. Construct validity of the DII indicates its utility for assessing the inflammatory potential of diet and for expanding its use to include associations with common chronic diseases in future studies.

Anticancer effect of COX-2 inhibitor DuP-697 alone and in combination with tyrosine kinase inhibitor (E7080) on colon cancer cell lines

Colorectal cancer remains one of the most common types of cancer and a leading cause of cancer death worldwide. In this study, we aimed to investigate effects of DuP-697, an irreversible selective inhibitor of COX- 2 on colorectal cancer cells alone and in combination with a promising new multi-targeted kinase inhibitor E7080. The HT29 colorectal cancer cell line was used. Real time cell analysis (xCELLigence system) was conducted to determine effects on colorectal cell proliferation, angiogenesis was assessed with a chorioallantoic membrane model and apoptosis was determined with annexin V staining. We found that DuP-697 alone exerted antiproliferative, antiangiogenic and apoptotic effects on HT29 colorectal cancer cells. For the antiproliferative effect the half maximum inhibition concentration (IC50) was 4.28?10-8 mol/L. Antiangiogenic scores were 1.2, 0.8 and 0.5 for 100, 10 and 1 nmol/L DuP-697 concentrations, respectively. We detected apoptosis in 52% of HT29 colorectal cancer cells after administration of 100 nmol/L DuP-697. Also in combination with the thyrosine kinase inhibitor E7080 strong antiproliferative, antiangiogenic and apoptotic effects on HT29 colorectal cancer cells were observed. This study indicates that DuP-697 may be a promising agent in the treatment of colorectal cancer. Additionally the increased effects observed in the combination with thyrosine kinase inhibitor give the possibility to use lower doses of DuP-697 and E7080 which can avoid and/or minimize side effects.

Variable NF-κB pathway responses in colon cancer cells treated with chemotherapeutic drugs

Background

The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway is activated in cells exposed to various stimuli, including those originating on the cell surface or in the nucleus. Activated NF-κB signaling is thought to enhance cell survival in response to these stimuli, which include chemotherapy and radiation. In the present effort, we determined which anticancer drugs preferentially activate NF-κB in colon cancer cells.

Methods

NF-κB reporter cells were established and treated with 5-fluorouracil (5-FU, DNA/RNA damaging), oxaliplatin (DNA damaging), camptothecin (CTP, topoisomerase inhibitor), phleomycin (radiomimetic), or erlotinib (EGFR inhibitor). The activation of NF-κB was assessed by immunofluorescence for p65 translocation, luciferase assays, and downstream targets of NF-κB activation (cIAP2, and Bcl-X_L) were evaluated by immunoblotting, by ELISA (CXCL8 and IL-6 in culture supernatants), or by gene expression analysis.

Results

Colon cancer cells responded variably to different classes of therapeutic agents, and these agents initiated variable responses among different cell types. CPT activated NF-κB in SW480 colon cancer cells in a dose-dependent manner, but not in HCT116 cells that were either wild-type or deficient for p53. In SW480 colon cancer cells, NF-κB activation by CPT was accompanied by secretion of the cytokine CXCL8, but not by up-regulation of the anti-apoptotic genes, cIAP2 or Bcl-X_L. On the contrary, treatment of HCT116 cells with CPT resulted in up-regulation of CXCR2, a receptor for CXCL8, without an increase in cytokine levels. In SW480 cells, NF-κB reporter activity, but not cytokine secretion, was inhibited by SM-7368, an NF-κB inhibitor.

Conclusion

The results show that, in response to cancer therapeutic agents, NF-κB activation varies with the cellular make up and that drug-induced NF-κB activation may be functionally uncoupled from anti-apoptotic outcomes found for other stimuli. Some cancer cells in a heterogeneous tumor tissue may, under therapeutic pressure, release soluble factors that have paracrine activity on neighboring cells that express the cognate receptors.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-599) contains supplementary material, which is available to authorized users.

Tolfenamic acid induces apoptosis and growth inhibition in anaplastic thyroid cancer: Involvement of nonsteroidal anti-inflammatory drug-activated gene-1 expression and intracellular reactive oxygen species generation

Nonsteroidal anti-inflammatory drugs (NSAIDs) are usually used for the treatment of inflammatory diseases. However, certain NSAIDs also have antitumor activities in various cancers, including head and neck cancer, through cyclooxygenase-dependent or independent pathways. Nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1), a TGF-β superfamily protein, is induced by NSAIDs and has been shown to be induced by several antitumorigenic compounds and to exhibit proapoptotic and antitumorigenic activities. In this report, we demonstrate for the first time that tolfenamic acid (TA) transcriptionally induced the expression of NAG-1 during TA-induced apoptosis of anaplastic thyroid cancer (ATC) cells. TA reduced the viability of ATC cells in a dose-dependent manner and induced apoptosis, findings that were coincident with NAG-1 expression. Overexpression of the NAG-1 gene using cDNA enhanced the apoptotic effect of TA, whereas suppression of NAG-1 expression by small interfering RNA attenuated TA-induced apoptosis. Subsequently, we found that intracellular ROS generation plays an important role in activating the proapoptotic protein NAG-1. Then, we confirmed antitumorigenic effects of TA in a nude mouse orthotopic ATC model, and this result accompanied the augmentation of NAG-1 expression and ROS generation in tumor tissue. Taken together, these results demonstrate that TA induces apoptosis via NAG-1 expression and ROS generation in in vitro and in vivo ATC models, providing a novel mechanistic explanation and indicating a potential chemotherapeutic approach for treatment of ATC.

Physical activity, tumor PTGS2 expression, and survival in patients with colorectal cancer

BACKGROUND

Higher levels of physical activity are associated with lower colorectal carcinoma incidence and mortality, perhaps through influencing energy balance, cellular prosta7 systemic inflammation. Although evidence suggests interactive effects of energetics, sedentary lifestyle, and tumor CTNNB1 (β-catenin) or CDKN1B (p27) status on colon cancer prognosis, interactive effects of physical activity and tumor PTGS2 (the official symbol for COX-2) status on clinical outcome remain unknown.

METHODS

Using molecular pathological epidemiology database of 605 stage I-III colon and rectal cancers in two prospective cohort studies (the Nurse's Health Study and the Health Professionals Follow-up Study), we examined patient survival according to postdiagnosis physical activity and tumor PTGS2 status (with 382 PTGS2-positive and 223 PTGS2-negative tumors by immunohistochemistry). Cox proportional hazards models were used to calculate colorectal cancer-specific mortality HR, adjusting for clinical and other tumor variables including microsatellite instability status.

RESULTS

Among PTGS2-positive cases, compared with the least active first quartile, the multivariate HRs (95% confidence interval) were 0.30 (0.14-0.62) for the second, 0.38 (0.20-0.71) for the third, and 0.18 (0.08-0.41) for the fourth quartile of physical activity level (Ptrend = 0.0002). In contrast, among PTGS2-negative cases, physical activity level was not significantly associated with survival (Ptrend = 0.84; Pinteraction = 0.024, between physical activity and tumor PTGS2 status).

CONCLUSIONS

Postdiagnosis physical activity is associated with better survival among patients with PTGS2-positive tumors but not among patients with PTGS2-negative tumors.

IMPACT

Immunohistochemical PTGS2 expression in colorectal carcinoma may serve as a predictive biomarker in pathology practice, which may predict stronger benefit from exercise.