Statin use is associated with a reduced incidence of colorectal cancer expressing SMAD4.

BACKGROUND: Long-term use of statins is associated with a small reduced risk of colorectal cancer but their mechanism of action is not well understood. While they are generally believed to act on KRAS, we have previously proposed that they act via influencing the BMP pathway. The objective of this study was to look for associations between statin use and the risk of developing colorectal cancer of a particular molecular subtype. METHODS: By linking two registries unique to the Netherlands, 69,272 statin users and 94,753 controls were identified and, if they developed colorectal cancer, their specimens traced. Colorectal cancers were molecularly subtyped according to the expression of SMAD4 and the mutation status of KRAS and BRAF. RESULTS: Statin use was associated with a reduction in the risk of developing colorectal cancer regardless of molecular subtype (HR 0.77; 95% CI 0.66-0.89) and a larger reduction in the risk of developing SMAD4-positive colorectal cancer (OR 0.64; 95% CI 0.42-0.82). There was no relationship between statin use and the risk of developing colorectal cancer with a mutation in KRAS and/or BRAF. CONCLUSIONS: Statin use is associated with a reduced risk of developing colorectal cancer with intact SMAD4 expression.

Deficits in Geriatric Assessment Associate With Disease Activity and Burden in Older Patients With Inflammatory Bowel Disease.

BACKGROUND & AIMS: We aimed to perform geriatric assessment in older patients with inflammatory bowel disease (IBD) to evaluate which IBD characteristics associate with deficits in geriatric assessment and the impact of deficits on disease burden (health-related quality of life). METHODS: A prospective multicenter cohort study including 405 consecutive outpatient patients with IBD aged ≥65 years. Somatic domain (comorbidity, polypharmacy, malnutrition), impairments in (instrumental) activities of daily living, physical capacity (handgrip strength, gait speed), and mental (depressive symptoms, cognitive impairment) and social domain (life-partner) were assessed. Deficits in geriatric assessment were defined as ≥2 abnormal domains; 2-3 moderate deficits and 4-5 severe deficits. Clinical (Harvey Bradshaw Index >4/partial Mayo Score >2) and biochemical (C-reactive protein ≥10 mg/L and/or fecal calprotectin ≥250 µg/g) disease activity and disease burden (short Inflammatory Bowel Disease Questionnaire) were assessed. RESULTS: Somatic domain (51.6%) and activities of daily living (43.0%) were most frequently impaired. A total of 160 (39.5%) patients had moderate deficits in their geriatric assessment; 32 (7.9%) severe. Clinical and biochemical disease activity associated with deficits (clinical: adjusted odds ratio, 2.191; 95% confidence interval, 1.284-3.743; P = .004; biochemical: adjusted odds ratio, 3.358; 95% confidence interval, 1.936-5.825; P < .001). Deficits in geriatric assessment independently associate with lower health-related quality of life. CONCLUSION: Deficits in geriatric assessment are highly prevalent in older patients with IBD. Patients with active disease are more prone to deficits, and deficits associate with lower health-related quality of life, indicating higher disease burden. Prospective data validating impact of frailty and geriatric assessment on outcomes are warranted to further improve treatment strategies.

Kinome-wide analysis of the effect of statins in colorectal cancer.

BACKGROUND: Epidemiological studies and meta-analyses show an association between statin use and a reduced incidence of colorectal cancer (CRC). We have shown that statins act on CRC through bone morphogenetic protein (BMP) signalling, but the exact cellular targets and underlying mechanism of statin action remain elusive. In this study, we set out to assess the influence of statins on global cancer cell signalling by performing an array-based kinase assay using immobilised kinase substrates spanning the entire human kinome. METHODS: CRC cells with or without Lovastatin treatment were used for kinome analysis. Findings on kinome arrays were further confirmed by immunoblotting with activity-specific antibodies. Experiments in different CRC cell lines using immunoblotting, siRNA-mediated knockdown and treatment with specific BMP inhibitor Noggin were performed. The relevance of in vitro findings was confirmed in xenografts and in CRC patients treated with Simvastatin. RESULTS: Kinome analysis can distinguish between non-specific, toxic effects caused by 10 µM of Lovastatin and specific effects on cell signalling caused by 2 µM Lovastatin. Statins induce upregulation of PTEN activity leading to downregulation of the PI3K/Akt/mTOR signalling. Treatment of cells with the specific BMP inhibitor Noggin as well as PTEN knockdown and transfection of cells with a constitutively active form of AKT abolishes the effect of Lovastatin on mTOR phosphorylation. Experiments in xenografts and in patients treated with Simvastatin confirm statin-mediated BMP pathway activation, activation of PTEN and downregulation of mTOR signalling. CONCLUSIONS: Statins induce BMP-specific activation of PTEN and inhibition of PI3K/Akt/mTOR signalling in CRC.

Statin Use After Diagnosis of Colon Cancer and Patient Survival.

BACKGROUND & AIMS: Statin use has been associated with a reduced incidence of colorectal cancer and might also affect survival of patients diagnosed with colon cancer. Statins are believed to inhibit Ras signaling and may also activate the bone morphogenetic protein (BMP) signaling pathway in colorectal cancer cells. We investigated the effects of statins on overall survival of patients with a diagnosis of colon cancer, and whether their effects were associated with changes in KRAS or the BMP signaling pathways. METHODS: Data were derived from the PHARMO database network (Netherlands) and linked to patients diagnosed with colon cancer from 2002 through 2007, listed in the Eindhoven Cancer Registry. We obtained information on causes of death from statistics Netherlands. We constructed a tissue microarray of 999 colon cancer specimens from patients who underwent surgical resection from 2002 through 2008. Survival was analyzed with statin user status after diagnosis as a time-dependent covariate. Multivariable Poisson regression survival models and Cox analyses were used to study the effect of statins on survival. Tumor tissues were analyzed by immunohistochemistry for levels of SMAD4, BMPR1A, BMPR1B, and BMPR2 proteins. Tumor tissues were considered to have intact BMP signaling if they contained SMAD4 plus BMPR1A, BMPR1B, or BMPR2. DNA was isolated from tumor tissues and analyzed by quantitative polymerase chain reaction to detect mutations in KRAS. The primary outcome measures were overall mortality and cancer-specific mortality. RESULTS: In this cohort, 21.0% of the patients (210/999) were defined as statin users after diagnosis of colon cancer. Statin use after diagnosis was significantly associated with reduced risk of death from any cause (adjusted relative risk [RR], 0.67; 95% confidence interval [CI], 0.51-0.87; P = .003) and death from cancer (adjusted RR, 0.66; 95% CI, 0.49-0.89; P = .007). Statin use after diagnosis was associated with reduced risk of death from any cause or from cancer for patients whose tumors had intact BMP signaling (adjusted RR, 0.39; 95% CI, 0.22-0.68; P = .001), but not for patients whose tumors did not have BMP signaling (adjusted RR, 0.81; 95% CI, 0.55-1.21; P = .106; P < .0001 for the interaction). Statin use after diagnosis was not associated with reduced risk of death from any cause or from cancer for patients whose tumors did not contain KRAS mutations (adjusted RR, 0.81; 95% CI, 0.56-1.18; P = .273) or whose tumors did have KRAS mutations (adjusted RR, 0.59; 95% CI 0.35-1.03; P = .062; P = .90 for the interaction). CONCLUSIONS: In an analysis of 999 patients with a diagnosis of colon cancer, we associated statin with reduced risk of death from any cause or from cancer. The benefit of statin use is greater for patients whose tumors have intact BMP signaling, independent of KRAS mutation status. Randomized controlled trials are required to confirm these results.

Loss of SMAD4 alters BMP signaling to promote colorectal cancer cell metastasis via activation of Rho and ROCK.

BACKGROUND & AIMS: SMAD4 frequently is lost from colorectal cancers (CRCs), which is associated with the development of metastases and a poor prognosis. SMAD4 loss is believed to alter transforming growth factor ß signaling to promote tumor progression. However, SMAD4 is also a central component of the bone morphogenetic protein (BMP) signaling pathway, implicated in CRC pathogenesis by human genetic studies. We investigated the effects of alterations in BMP signaling on the invasive and metastatic abilities of CRC cells and changes in members in this pathway in human tumor samples. METHODS: We activated BMP signaling in SMAD4-positive and SMAD4-negative CRC cells (HCT116, HT-29, SW480, and LS174T); SMAD4 was stably expressed or knocked down using lentiviral vectors. We investigated the effects on markers of epithelial-mesenchymal transition and on cell migration, invasion, and formation of invadopodia. We performed kinase activity assays to characterize SMAD4-independent BMP signaling and used an inhibitor screen to identify pathways that regulate CRC cell migration. We investigated the effects of the ROCK inhibitor Y-27632 in immunocompromised (CD-1 Nu) mice with orthotopic metastatic tumors. Immunohistochemistry was used to detect BMPR1a, BMPR1b, BMPR2, and SMAD4 in human colorectal tumors; these were related to patient survival times. RESULTS: Activation of BMP signaling in SMAD4-negative cells altered protein and messenger RNA levels of markers of epithelial-mesenchymal transition and increased cell migration, invasion, and formation of invadopodia. Knockdown of the BMP receptor in SMAD4-negative cells reduced their invasive activity in vitro. SMAD4-independent BMP signaling activated Rho signaling via ROCK and LIM domain kinase (LIMK). Pharmacologic inhibition of ROCK reduced metastasis of colorectal xenograft tumors in mice. Loss of SMAD4 from colorectal tumors has been associated with reduced survival time; we found that this association is dependent on the expression of BMP receptors but not transforming growth factor ß receptors. CONCLUSIONS: Loss of SMAD4 from colorectal cancer cells causes BMP signaling to switch from tumor suppressive to metastasis promoting. Concurrent loss of SMAD4 and normal expression of BMP receptors in colorectal tumors was associated with reduced survival times of patients. Reagents that interfere with SMAD4-independent BMP signaling, such as ROCK inhibitors, might be developed as therapeutics for CRC.

Deficits in geriatric assessment are important in relation to fatigue in older patients with Inflammatory Bowel Disease.

BACKGROUND: No previous study has investigated fatigue in older patients with Inflammatory Bowel Disease (IBD). AIMS: To describe the prevalence of fatigue in older patients and compare it to the prevalence in younger patients with IBD, and to determine factors associated with fatigue. METHODS: A prospective, multicenter cohort study, including older- (≥ 65 years) and younger patients with IBD (18-64 years). A geriatric assessment was performed in older patients to measure deficits in geriatric assessment (DiG). Fatigue was defined by one item from the short Inflammatory Bowel Disease Questionnaire. Active disease was defined as the presence of clinical or biochemical disease activity. RESULTS: Fatigue prevalence in the 405 older patients varied between 45.4% (71/155) in active disease to 23.6% (60/250) in remission. Fatigue prevalence in 155 younger patients was 59.5% (47/79) and 57.4% (89/155), respectively. Female sex, clinical disease activity, use of immunomodulators and presence of DiG were associated with fatigue in older patients with IBD. CONCLUSIONS: Fatigue prevalence is lower in older patients with IBD compared to younger patients with IBD, but increases when active disease is present. Clinicians should be aware that fatigue is a relevant symptom in older patients with IBD, as it is associated with DiG.

Frailty screening associates with hospitalization and decline in quality of life and functional status in older patients with inflammatory bowel disease.

BACKGROUND AND AIMS: To study frailty screening in association with hospitalization and decline in quality of life (QoL) and functional status in older patients with Inflammatory Bowel Diseases (IBD). METHODS: A prospective multicentre cohort study in IBD patients ≥65 years using frailty screening (G8 Questionnaire). Outcomes were all-cause, acute and IBD-related hospitalization, any infection, any malignancy, QoL (EQ5D-3L) and functional decline (Instrumental Activities of Daily Living, (IADL)) during 18 months follow-up. Confounders: age, IBD type, biochemical disease activity (C-reactive protein ≥10 mg/L and/or fecal calprotectin ≥250 µg/g), comorbidity (Charlson Comorbidity Index). RESULTS: Out of 405 patients, median age 70 years, 196 (48%) screened at risk for frailty. All-cause hospitalizations occurred 136 times in 96 patients (23.7%), acute hospitalizations 103 times in 74 (18.3%). Risk of frailty did not associate with all-cause (aHR 1.5, 95% CI 0.9-2.4), but did associate with acute hospitalizations (aHR 2.2, 95% CI 1.3-3.8). Infections occurred in 86 patients (21.2%) and were not associated with frailty. Decline in QoL was experienced by 108 (30.6%) patients, decline in functional status by 46 (13.3%). Frailty screening associated with decline in QoL (aOR 2.1, 95% CI 1.3-3.6) and functional status (aOR 3.7, 95% CI 1.7-8.1). CONCLUSIONS: Frailty screening associates with worse health outcomes in older patients with IBD. Further studies are needed to assess feasibility and effectiveness of implementation in routine care.

Statins augment the chemosensitivity of colorectal cancer cells inducing epigenetic reprogramming and reducing colorectal cancer cell 'stemness' via the bone morphogenetic protein pathway.

BACKGROUND: Promoter hypermethylation is an important and potentially reversible mechanism of tumour suppressor gene silencing in cancer. Compounds that demethylate tumour suppressor genes and induce differentiation of cancer cells, but do not have toxic side effects, would represent an exciting option in cancer therapy. Statins are cholesterol-lowering drugs with an excellent safety profile and associated with a reduced incidence of various cancers including colorectal cancer (CRC). The authors have previously shown that statins act by activating tumour suppressive bone morphogenetic protein (BMP) signalling in CRC, increasing expression of BMP2. BMP2 is silenced by hypermethylation in gastric cancer. AIM: To investigate whether BMP2 is methylated in CRC, whether statins can reverse this, and what implications this has for the use of statins in CRC. METHODS: Methylation-specific PCR, bisulphite sequencing, immunoblotting, reverse transcription PCR, quantitative PCR, fluorescence-activated cell sorting analysis, an in vitro DNA methyltransferase (DNMT) assay, and cell viability studies were performed on CRC cells. The effect of statins was confirmed in a xenograft mouse model. Results BMP2 is silenced by promoter hypermethylation in cell lines with the hypermethylator phenotype and in primary tumours. Treatment with lovastatin downregulates DNMT activity, leading to BMP2 promoter demethylation and to upregulation of expression of BMP2 as well as other genes methylated in CRC. Statins alter gene expression, indicating a shift from a stem-like state to a more differentiated state, thereby sensitising cells to the effects of 5-fluorouracil. In a xenograft mouse model, simvastatin treatment induces BMP2 expression, leading to differentiation and reduced proliferation of CRC cells. CONCLUSIONS: Statins act as DNMT inhibitors, demethylating the BMP2 promoter, activating BMP signalling, inducing differentiation of CRC cells, and reducing 'stemness'. This study indicates that statins may be able to be used as differentiating agents in combined or adjuvant therapy in CRC with the CpG island methylator phenotype.

The role of EZH2 and DNA methylation in the silencing of the tumour suppressor RUNX3 in colorectal cancer.

In gastric cancer, a new epigenetic mechanism of tumour suppressor loss has been suggested where the histone methyltransferase enhancer of zeste homolog 2 (EZH2) is responsible for loss of expression of RUNX3. This is consistent with EZH2 upregulation in multiple cancer types being associated with poor prognosis. We investigated whether EZH2 influences the expression of RUNX3 in colorectal cancer (CRC) and whether this is independent of methylation. We determined protein and messenger RNA (mRNA) levels of EZH2 and RUNX3 and assessed RUNX3 methylation with methylation-specific polymerase chain reaction using 72 human CRCs and 8 CRC cell lines. We assessed the effect of efficient RNA interference-mediated knockdown of EZH2 on RUNX3 levels, cell viability and H3K27 trimethylation of the RUNX3 promoter using chromatin immunoprecipitation. Despite higher levels of EZH2 and lower levels of RUNX3 in CRC specimens in general, no inverse correlation between EZH2 and RUNX3 in paired samples was found arguing against a major role for histone methylation in silencing RUNX3 in CRC. Conversely, downregulation of RUNX3 mRNA in the same tumours was associated with RUNX3 DNA methylation (P < 0.05). In cell lines, knockdown of EZH2 removed the repressive chromatin marks from RUNX3 but did not result in RUNX3 re-expression. However, it prevented the re-silencing of RUNX3 after the removal of demethylating agents. In conclusion, DNA methylation is primarily responsible for the transcriptional silencing of RUNX3 in CRC, but EZH2 and histone methylation are necessary for its methylation-dependent re-silencing after the removal of demethylating agents. These results would predict that inhibitors of EZH2 and histone methylation would enhance the effects of demethylating agents in cancer therapy.

A Meta-Analysis of SMAD4 Immunohistochemistry as a Prognostic Marker in Colorectal Cancer.

AIM: SMAD4 immunohistochemistry is considered a valuable prognostic marker in colorectal cancer, but individual studies have often been small and the results variable. A meta-analysis could potentially clarify these findings. METHODS: In September 2014, a Pubmed and Google Scholar search was conducted to find publications that reported the prognostic value of SMAD4 expression. A meta-analysis was performed to clarify the association between SMAD4 expression and survival outcomes. RESULTS: 137 studies were found, of which 13 were considered eligible. The studies consisted of a total of 3800 patients. Three different endpoints were taken into account, namely, overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS). In addition, the studies were divided into univariate and multivariate analyses. The pooled hazard ratios were given as follows: univariate CSS = 1.75 [95% confidence interval (CI): 0.93-3.32; z= 1.69; P= .09]; multivariate CSS = 2.17 (95% CI: 1.56-3.01; z= 4.65; P= .000); univariate DFS = 2.11 (95% CI: 1.36-3.28; z= 3.32; P= .001); multivariate DFS = 2.15 (95% CI: 1.56-3.01; z= 4.65; P= .000); univariate OS and DFS = 2.30 (95% CI: 1.41-3.73; z= 3.36; P= .001); univariate OS = 2.28 (95% CI: 1.30-4.00; z= 2.89; P= .004). CONCLUSION: The results of the presented meta-analyses indicate that SMAD4 expression status using immunohistochemistry is a prognostic marker for patient survival.

Evaluation of the prognostic value of pSMAD immunohistochemistry in colorectal cancer.

SMAD4 mutations and recent genome-wide association studies (GWAS) show the importance of bone morphogenetic protein (BMP) and transforming growth factor-ß (TGF-ß) signalling in the development of colorectal cancer (CRC). Loss of SMAD4 has been implicated as a predictive marker in CRC. As activation of the BMP and TGF-ß pathways leads to phosphorylation of SMAD1,5,8 and SMAD2,3, respectively, and both need SMAD4 for translocation to the nucleus, we aimed to investigate whether nuclear staining of pSMAD1,5,8 and pSMAD2, 3 can be used as predictive markers in CRC. A tissue microarray (TMA) was constructed using tissue from 209 patients diagnosed with CRC. TMA was stained and scored for the nuclear presence of SMAD4, pSMAD2,3 and pSMAD1,5,8. Loss of SMAD4, pSMAD2,3 and pSMAD1,5,8 was observed in 40, 38 and 73% of the cases, respectively. The incidence of SMAD4 loss was significantly higher in the advanced stages. There was a correlation between loss of SMAD4 and loss of pSMAD1,5,8, but not between loss of SMAD4 and loss of pSMAD2,3. Loss of SMAD4 correlated with a poorer survival. Loss of one of the pSMADs did not correlate with a poorer outcome. Combining different SMAD stainings did not improve the prediction. SMAD4 expression is a prognostic marker in CRC. Nuclear expressions of pSMAD1,5,8 and pSMAD2,3 are not useful prognostic markers in CRC.

Correction: Intestinal Tumorigenesis Is Not Affected by Progesterone Signaling in Rodent Models.

[This corrects the article DOI: 10.1371/journal.pone.0022620.].

Cholesterol metabolism and colorectal cancers.

Colorectal cancer (CRC) is primarily a lifestyle disease of the western world. As such it can be likened to cardiovascular disease and indeed it shares many of the same risk factors. It is therefore perhaps unsurprising that cholesterol metabolism and colorectal cancer are also intricately linked. Many of the initial studies suggesting a link between dietary cholesterol, blood cholesterol levels and cholesterol lowering drugs were performed more than a decade ago. The most recent insights in this field are the result of meta-analyses, advances in pharmacogenetics and the new field of molecular pathological epidemiology. This review summarises the current evidence linking cholesterol metabolism with colorectal cancer including the suggested underlying molecular causes and the implications for colorectal cancer prevention.

The potential of statins for individualized colorectal cancer chemoprevention.

Colorectal cancer is a leading cause of death by cancer in the western world. Despite major progress, even new chemotherapeutic regimens have had relatively little impact on long term survival in the approximately 50% of patients with advanced disease at presentation meaning that prevention is the only realistic way to reduce the burden of this disease. Many countries have implemented population-based screening methods to prevent colorectal cancer by the physical removal of its precursor lesion the adenoma, or to detect cancer at an earlier stage when it is amenable to surgical cure. However these programs have only been shown to reduce colorectal cancer deaths by 30% in those screened and therefore new or complimentary approaches are needed. One such approach is chemoprevention. A number of compounds have shown potential in reducing the incidence of colorectal cancer. Most widely known are NSAIDs but recently inhibitors of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, also known as statins, commonly prescribed medications that lower serum cholesterol, have been shown to reduce colorectal cancer incidence. A critical issue in chemoprevention is the weighing of benefits against risks. In chemoprevention this balance is likely to be unfavourable when used in a wide unselected population even for the safest of compounds. Therapy should therefore be tailored to the individual patient. The balance will be more favourable in high risk groups such as individuals especially susceptible to neoplasia because of environmental risk factors, patients with inflammatory bowel disease, those with a hereditary predisposition and patients with a previous history of colorectal cancer or polyps. Furthermore colorectal cancer is not one disease but a heterogeneous group of diseases with different underlying molecular mechanisms. It is likely that both prevention and therapy will need to be tailored to the molecular subtype of the cancer in question. This may explain why studies of colorectal cancer in statin users do not show consistent protective effects. Evidence in vitro has shown a dichotomous effect of statins with either a cancer inhibiting or cancer promoting effect depending on their molecular subtype. Further studies are needed to determine in which patient groups statins can be used to prevent colorectal cancer and whether in other patients groups they should be avoided.

Intestinal tumorigenesis is not affected by progesterone signaling in rodent models.

Clinical data suggest that progestins have chemopreventive properties in the development of colorectal cancer. We set out to examine a potential protective effect of progestins and progesterone signaling on colon cancer development. In normal and neoplastic intestinal tissue, we found that the progesterone receptor (PR) is not expressed. Expression was confined to sporadic mesenchymal cells. To analyze the influence of systemic progesterone receptor signaling, we crossed mice that lacked the progesterone receptor (PRKO) to the Apc(Min/+) mouse, a model for spontaneous intestinal polyposis. PRKO-Apc(Min/+) mice exhibited no change in polyp number, size or localization compared to Apc(Min/+). To examine effects of progestins on the intestinal epithelium that are independent of the PR, we treated mice with MPA. We found no effects of either progesterone or MPA on gross intestinal morphology or epithelial proliferation. Also, in rats treated with MPA, injection with the carcinogen azoxymethane did not result in a difference in the number or size of aberrant crypt foci, a surrogate end-point for adenoma development. We conclude that expression of the progesterone receptor is limited to cells in the intestinal mesenchyme. We did not observe any effect of progesterone receptor signaling or of progestin treatment in rodent models of intestinal tumorigenesis.