Aspirin Prevents Colorectal Cancer by Normalizing EGFR Expression

Erlotinib suppresses tumorigenesis in a mouse model of colitis-associated cancer

Colitis-associated cancer (CAC) in inflammatory bowel diseases exhibits more aggressive behavior than sporadic colorectal cancer; however, the molecular mechanisms remain unclear. No definitive preventative agent against CAC is currently established in the clinical setting. We investigated the molecular mechanisms of CAC in the azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model and assessed the antitumor efficacy of erlotinib, a small molecule inhibitor of the epidermal growth factor receptor (EGFR). Erlotinib premixed with AIN-93 G diet at 70 or 140 parts per million (ppm) inhibited tumor multiplicity significantly by 96%, with ∼60% of the treated mice exhibiting zero polyps at 12 weeks. Bulk RNA-sequencing revealed more than a thousand significant gene alterations in the colons of AOM/DSS-treated mice, with KEGG enrichment analysis highlighting 46 signaling pathways in CAC development. Erlotinib altered several signaling pathways and rescued 40 key genes dysregulated in CAC, including those involved in the Hippo and Wnt signaling. These findings suggest that the clinically-used antitumor agent erlotinib might be repurposed for suppression of CAC, and that further studies are warranted on the crosstalk between dysregulated Wnt and EGFR signaling in the corresponding patient population.

Effects of aspirin on colon cancer using quantitative proteomic analysis

Background

Colon cancer is one of the most prevalent digestive cancers worldwide. Results of epidemiological, experimental, and clinical studies suggest that aspirin inhibits the development of colon cancer. This study aimed to systematically elucidate the molecular mechanisms by which aspirin prevents colon carcinogenesis.

Methods

We determined the global protein expression profiles of colorectal cancer and aspirin-treated cells using quantitative proteomic analysis. We analyzed the proteomic results using bioinformatics (including differential proteins, protein annotation, Kyoto Encyclopedia of Genes and Genomes [KEGG] pathways, and protein-protein interaction [PPI] network). The viability of the colon cancer cell line and HT29 ​cells treated with aspirin was determined using the cell counting kit-8 assay. The differentially expressed proteins, such as p53 and cyclin-dependent kinase 1 (CDK1), were quantified using real-time polymerase chain reaction (PCR) and Western blotting. We measured cell cycle distribution and apoptosis in HT29 ​cells exposed to aspirin using fluorescence-activated cell sorting (FACS).

Results

We found that 552 proteins were significantly dysregulated, of which 208 and 334 were upregulated and downregulated, respectively, in colon cancer cells exposed to 10 ​mmol/L of aspirin (95% confidence interval [CI]: -1.269 to -0.106, P ​< ​0.05). Further gene enrichment analysis revealed that cell cycle-related proteins, such as p53 and CDK1, were significantly differentially expressed. Proteomic analysis showed that after 24 ​h of aspirin exposure, the level of p53 increased by 2.52-fold and CDK1 was downregulated to half that of the controls in HT29 ​cells (95% CI: -0.619 to -0.364, P ​< ​0.05). Real-time PCR and Western blotting results showed that p53 was upregulated (95%CI: -3.088 to -1.912, P ​< ​0.001) and CDK1 was significantly downregulated after aspirin exposure in colon cancer cells (95% CI: 0.576 to 1.045, P ​< ​0.05). We observed that aspirin promoted G1/S cell cycle arrest in HT29 ​cells. We confirmed that aspirin induces apoptosis in human HT29 colon cancer cells in a concentration-dependent manner.

Conclusions

These results indicate that aspirin induces G1 arrest and apoptosis in colorectal cancer cells via the p53-CDK1 pathway. Aspirin may be a promising drug candidate for colon cancer prevention.

Cost-effectiveness of preventive aspirin use and intensive downstaging polypectomy in patients with familial adenomatous polyposis: A microsimulation modeling study

OBJECTIVE

Although there is increasing evidence to suggest the cost-effectiveness of aspirin use to prevent colorectal cancer (CRC) in the general population, no study has assessed cost-effectiveness in patients with familial adenomatous polyposis (FAP), who are at high risk of developing CRC. We examined the cost-effectiveness of preventive use of low-dose aspirin in FAP patients who had undergone polypectomy in comparison with current treatment practice.

DESIGN

We developed a microsimulation model that simulates a hypothetical cohort of the Japanese population with FAP for 40 years. Three scenarios were created based on three intervention strategies for comparison with no intervention, namely intensive downstaging polypectomy (IDP) of colorectal polyps at least 5.0 mm in diameter, IDP combined with low-dose aspirin, and total proctocolectomy with ileal pouch-anal anastomosis (IPAA). Cost-effective strategies were identified using a willingness-to-pay threshold of USD 50,000 per QALY gained.

RESULTS

Compared with no intervention, all strategies resulted in extended QALYs (21.01-21.43 QALYs per individual) and showed considerably reduced colorectal cancer mortality (23.35-53.62 CRC deaths per 1000 individuals). Based on the willingness-to-pay threshold, IDP with low-dose aspirin was more cost-effective than the other strategies, with an incremental cost-effectiveness ratio of $57 compared with no preventive intervention. These findings were confirmed in both one-way sensitivity analyses and probabilistic sensitivity analyses.

CONCLUSION

This study suggests that the strategy of low-dose aspirin with IDP may be cost-effective compared with IDP-only or IPAA under the national fee schedule of Japan.

Stress granules affect the sensitivity of renal cancer cells to sorafenib by sequestering and stabilizing COX‑2 mRNA

Most patients with renal cancer will develop resistance to sorafenib therapy and will therefore exhibit disease progression. Effective therapies for these patients are extremely limited. Cyclooxygenase-2 (COX-2) promotes the malignant transformation of cancer cells and drug resistance. The potential of COX-2 inhibitor (celecoxib) administration in combination with sorafenib for the treatment of renal cancer is unclear. The present study demonstrated that sorafenib rapidly increased the expression of COX-2 in renal cancer cells, as determined using reverse transcription-quantitative PCR and western blotting. The results of the MTT assay and cell apoptosis experiment demonstrated that the cytotoxicity of sorafenib was also affected by COX-2 expression and celecoxib enhanced the cytotoxicity of sorafenib against renal cell carcinoma. Immunofluorescence analysis indicated that sorafenib induced the formation of stress granules (SGs) in renal cancer cells. In addition, COX-2 expression was associated with the formation of SGs, and SGs could capture and stabilize COX-2 mRNAs in renal cancer cells; this was confirmed using RNA fluorescence in situ hybridization and an actinomycin D chase experiment. The protective effect of SGs was further demonstrated in cell experiments and xenograft tumor models. Thus, the present study indicated that the use of celecoxib may significantly enhance the sensitivity of renal cancer cells to sorafenib and improve efficacy. Sorafenib-induced SGs may contribute to critical events that promote COX-2 expression and survival in renal cancer cells. Therefore, the present study may provide novel ideas for the treatment of renal cancer.

Cyclooxygenase and Lipoxygenase Gene Expression in the Inflammogenesis of Colorectal Cancer: Correlated Expression of EGFR, JAK STAT and Src Genes, and a Natural Antisense Transcript, RP11-C67.2.2

We examined the expression of major inflammatory genes, cyclooxygenase-1, 2 (COX1, COX2), arachidonate-5-lipoxygenase (ALOX5), and arachidonate-5-lipoxygenase activating protein (ALOX5AP) among 469 tumor specimens of colorectal cancer in The Cancer Genome Atlas (TCGA). Among 411 specimens without mutations in mismatch repair (MMR) genes, the mean expression of each of the inflammatory genes ranked above the 80th percentile, and the overall mean cyclooxygenase expression (COX1+COX2) ranked in the upper 99th percentile of all genes. Similar levels were observed for 58 cases with MMR mutations. Pearson correlation coefficients exceeding r = 0.70 were observed between COX and LOX mRNA levels with genes of major cell-signaling pathways involved in tumorigenesis (Src, JAK STAT, MAPK, PI3K). We observed a novel association (r = 0.78) between ALOX5 expression and a natural antisense transcript (NAT), RP11-67C2.2, a long non-coding mRNA gene, 462 base pairs in length that is located within the terminal intron of the ALOX5 gene on chromosome 10q11.21. Tumor-promoting genes highly correlated with the expression of COX1, COX2, ALOX5 and ALOX5AP are known to increase mitogenesis, mutagenesis, angiogenesis, cell survival, immunosuppression and metastasis in the inflammogenesis of colorectal cancer. These genes and the novel NAT, RP1167C2.2 are potential molecular targets for chemoprevention and therapy of colorectal cancer.

Updates on the molecular mechanisms of aspirin in the prevention of colorectal cancer: Review

Colorectal cancer is one of the commonest malignancies worldwide. The estimated lifetime risk of the disease is about 5% with an incidence of one million new cases and 600,000 deaths worldwide every year. It is estimated that in 2019, approximately 134,490 new cases of colorectal cancer will be diagnosed with 49,190 mortalities. Though the disease is regarded as a disorder of the more developed world, the occurrence is steadily increasing in many developing countries. Since chronic inflammation is a known aggravating risk factor for colorectal cancer, anti-inflammatory agents such as aspirin have been used to prevent the development of colorectal cancer and related mortality. The potential mechanisms for the effect of aspirin in the prevention of colorectal cancer have been proposed and broadly classified as cyclooxygenase (COX) dependent and COX-independent. Some of the primary effectors of COX-dependent mechanisms in carcinogenesis are likely to be prostaglandins. In contrast to the reversible action of other nonsteroidal anti-inflammatory drugs, aspirin is known to irreversibly inactivate COX enzymes to suppress production of prostaglandins. COX-independent mechanisms of anticancer effects of aspirin include down-regulation of nuclear factor kappa B activity and Akt activation, modulation of Bcl-2 and Bax family proteins, suppression of vascular endothelial growth factor, induction of apoptosis, disruption of DNA repair mechanisms, and induction of spermidine/spermine N¹-acetyltransferase that modulates polyamine catabolism.

Mechanisms of Colorectal Cancer Prevention by Aspirin-A Literature Review and Perspective on the Role of COX-Dependent and -Independent Pathways

Aspirin, synthesized and marketed in 1897 by Bayer, is one of the most widely used drugs in the world. It has a well-recognized role in decreasing inflammation, pain and fever, and in the prevention of thrombotic cardiovascular diseases. Its anti-inflammatory and cardio-protective actions have been well studied and occur through inhibition of cyclooxygenases (COX). Interestingly, a vast amount of epidemiological, preclinical and clinical studies have revealed aspirin as a promising chemopreventive agent, particularly against colorectal cancers (CRC); however, the primary mechanism by which it decreases the occurrences of CRC has still not been established. Numerous mechanisms have been proposed for aspirin’s chemopreventive properties among which the inhibition of COX enzymes has been widely discussed. Despite the wide attention COX-inhibition has received as the most probable mechanism of cancer prevention by aspirin, it is clear that aspirin targets many other proteins and pathways, suggesting that these extra-COX targets may also be equally important in preventing CRC. In this review, we discuss the COX-dependent and -independent pathways described in literature for aspirin’s anti-cancer effects and highlight the strengths and limitations of the proposed mechanisms. Additionally, we emphasize the potential role of the metabolites of aspirin and salicylic acid (generated in the gut through microbial biotransformation) in contributing to aspirin’s chemopreventive actions. We suggest that the preferential chemopreventive effect of aspirin against CRC may be related to direct exposure of aspirin/salicylic acid or its metabolites to the colorectal tissues. Future investigations should shed light on the role of aspirin, its metabolites and the role of the gut microbiota in cancer prevention against CRC.

Proteomics Reveal the Inhibitory Mechanism of Levodopa Against Esophageal Squamous Cell Carcinoma

High recurrence rates and poor survival of patients with esophageal squamous cell carcinoma (ESCC) after treatment make ongoing research on chemoprevention drugs for ESCC particularly important. In this study, we screened a large number of FDA-approved drugs and found levodopa, a drug used to treat Parkinson's disease, had an inhibitory effect on the growth of ESCC cells. To elucidate the molecular mechanisms involved, we applied quantitative proteomics to investigate the anti-tumor activity of levodopa on ESCC. The results suggest that levodopa could down-regulate oxidative phosphorylation, non-alcoholic fatty liver disease, and Parkinson's disease pathways. Major mitochondrial respiratory compounds were involved in the pathways, including succinate dehydrogenase subunit D, NADH-ubiquinone oxidoreductase Fe-S protein 4, and mitochondrial cytochrome c oxidase subunit 3. Down-regulation of these proteins was associated with mitochondrial dysfunction. Western blotting and immunofluorescence results confirmed the proteomics findings. Cell viability assays indicated mitochondrial activity was suppressed after levodopa treatment. Reduced mitochondrial membrane potential was detected using JC-1 staining and TMRE assays. Transmission electron microscopy revealed changes in the morphology of mitochondria. Taken together, these results indicate that levodopa inhibited the growth of ESCC through restraining mitochondria function.

Revealing new therapeutic opportunities through drug target prediction: a class imbalance-tolerant machine learning approach

MOTIVATION

In silico drug target prediction provides valuable information for drug repurposing, understanding of side effects as well as expansion of the druggable genome. In particular, discovery of actionable drug targets is critical to developing targeted therapies for diseases.

RESULTS

Here, we develop a robust method for drug target prediction by leveraging a class imbalance-tolerant machine learning framework with a novel training scheme. We incorporate novel features, including drug-gene phenotype similarity and gene expression profile similarity that capture information orthogonal to other features. We show that our classifier achieves robust performance and is able to predict gene targets for new drugs as well as drugs that potentially target unexplored genes. By providing newly predicted drug-target associations, we uncover novel opportunities of drug repurposing that may benefit cancer treatment through action on either known drug targets or currently undrugged genes.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Do Aspirin and Flavonoids Prevent Cancer through a Common Mechanism Involving Hydroxybenzoic Acids?-The Metabolite Hypothesis

Despite decades of research to elucidate the cancer preventive mechanisms of aspirin and flavonoids, a consensus has not been reached on their specific modes of action. This inability to accurately pinpoint the mechanism involved is due to the failure to differentiate the primary targets from its associated downstream responses. This review is written in the context of the recent findings on the potential pathways involved in the prevention of colorectal cancers (CRC) by aspirin and flavonoids. Recent reports have demonstrated that the aspirin metabolites 2,3-dihydroxybenzoic acid (2,3-DHBA), 2,5-dihydroxybenzoic acid (2,5-DHBA) and the flavonoid metabolites 2,4,6-trihydroxybenzoic acid (2,4,6-THBA), 3,4-dihydroxybenzoic acid (3,4-DHBA) and 3,4,5-trihydroxybenzoic acid (3,4,5-THBA) were effective in inhibiting cancer cell growth in vitro. Limited in vivo studies also provide evidence that some of these hydroxybenzoic acids (HBAs) inhibit tumor growth in animal models. This raises the possibility that a common pathway involving HBAs may be responsible for the observed cancer preventive actions of aspirin and flavonoids. Since substantial amounts of aspirin and flavonoids are left unabsorbed in the intestinal lumen upon oral consumption, they may be subjected to degradation by the host and bacterial enzymes, generating simpler phenolic acids contributing to the prevention of CRC. Interestingly, these HBAs are also abundantly present in fruits and vegetables. Therefore, we suggest that the HBAs produced through microbial degradation of aspirin and flavonoids or those consumed through the diet may be common mediators of CRC prevention.

Colorectal Cancer Among Gout Patients Undergoing Colonoscopy

BACKGROUND/OBJECTIVE

The connection between gout and various cancers remains unclear. We assessed the relationship between gout and colorectal cancer in a population of veterans.

METHODS

We reviewed the Computerized Patient Record System of the VA New York Harbor Health Care System to assess the 10-year occurrence of colorectal cancer in patients with gout undergoing colonoscopy, versus patients with osteoarthritis but no gout.

RESULTS

Gout and osteoarthritis subjects were similar in age, ethnicity, body mass index, and smoking history. Among 581 gout and 598 osteoarthritis subjects with documented colonoscopies, the 10-year prevalence of colorectal cancer was significantly lower in gout (0.8%) versus osteoarthritis (3.7%) (p = 0.0008) patients. Differences in colorectal cancer rates remained significant after stratifying for nonsteroidal anti-inflammatory drug use. Among gout subjects, use of colchicine and/or allopurinol, as well as the presence/absence of concomitant osteoarthritis, did not influence colorectal cancer occurrence. On subanalysis, differences in colorectal cancer occurrence between gout and osteoarthritis subjects persisted among those who underwent diagnostic (0.5% in gout vs 4.6% in osteoarthritis subjects, p < 0.001) but not screening (0.9% in gout subjects vs 1% in osteoarthritis subjects, p = 1.0) colonoscopy. There was no significant difference in nonmalignant colorectal polyp occurrence between gout and osteoarthritis subjects.

CONCLUSIONS

Subjects with gout had decreased colonoscopy-documented occurrence of colorectal cancer compared with osteoarthritis subjects, suggesting a possible protective effect.

Targeting the COX2/MET/TOPK signaling axis induces apoptosis in gefitinib-resistant NSCLC cells

MET overactivation is one of the crucial reasons for tyrosine kinase inhibitor (TKI) resistance, but the mechanisms are not wholly clear. Here, COX2, TOPK, and MET expression were examined in EGFR-activating mutated NSCLC by immunohistochemical (IHC) analysis. The relationship between COX2, TOPK, and MET was explored in vitro and ex vivo. In addition, the inhibition of HCC827GR cell growth by combining COX2 inhibitor (celecoxib), TOPK inhibitor (pantoprazole), and gefitinib was verified ex vivo and in vivo. We found that COX2 and TOPK were highly expressed in EGFR-activating mutated NSCLC and the progression-free survival (PFS) of triple-positive (COX2, MET, and TOPK) patients was shorter than that of triple-negative patients. Then, we observed that the COX2-TXA₂ signaling pathway modulated MET through AP-1, resulting in an inhibition of apoptosis in gefitinib-resistant cells. Moreover, we demonstrated that MET could phosphorylate TOPK at Tyr74 and then prevent apoptosis in gefitinib-resistant cells. In line with these findings, the combination of celecoxib, pantoprazole, and gefitinib could induce apoptosis in gefitinib-resistant cells and inhibit tumor growth ex vivo and in vivo. Our work reveals a novel COX2/MET/TOPK signaling axis that can prevent apoptosis in gefitinib-resistant cells and suggests that a triple combination of FDA-approved drugs would provide a low-cost and practical strategy to overcome gefitinib resistance.

Targeting the Canonical WNT/β-Catenin Pathway in Cancer Treatment Using Non-Steroidal Anti-Inflammatory Drugs

Chronic inflammation and oxidative stress are common and co-substantial pathological processes accompanying and contributing to cancers. Numerous epidemiological studies have indicated that non-steroidal anti-inflammatory drugs (NSAIDs) could have a positive effect on both the prevention of cancer and tumor therapy. Numerous hypotheses have postulated that NSAIDs could slow tumor growth by acting on both chronic inflammation and oxidative stress. This review takes a closer look at these hypotheses. In the cancer process, one of the major signaling pathways involved is the WNT/β-catenin pathway, which appears to be upregulated. This pathway is closely associated with both chronic inflammation and oxidative stress in cancers. The administration of NSAIDs has been observed to help in the downregulation of the WNT/β-catenin pathway and thus in the control of tumor growth. NSAIDs act as PPARγ agonists. The WNT/β-catenin pathway and PPARγ act in opposing manners. PPARγ agonists can promote cell cycle arrest, cell differentiation, and apoptosis, and can reduce inflammation, oxidative stress, proliferation, invasion, and cell migration. In parallel, the dysregulation of circadian rhythms (CRs) contributes to cancer development through the upregulation of the canonical WNT/β-catenin pathway. By stimulating PPARγ expression, NSAIDs can control CRs through the regulation of many key circadian genes. The administration of NSAIDs in cancer treatment would thus appear to be an interesting therapeutic strategy, which acts through their role in regulating WNT/β-catenin pathway and PPARγ activity levels.

Platelets and extracellular vesicles in cancer: diagnostic and therapeutic implications

Several pieces of evidence support the role of activated platelets in the development of the chronic inflammation-related diseases, such as atherothrombosis and cancer, mainly via the release of soluble factors and microparticles (MPs). Platelets and MPs contain a repertoire of proteins and genetic material (i.e., mRNAs and microRNAs) which may be influenced by the clinical condition of the individuals. In fact, platelets are capable of up-taking proteins and genetic material during their lifespan. Moreover, the content of platelet-derived MPs can be delivered to other cells, including stromal, immune, epithelial, and cancer cells, to change their phenotype and functions, thus contributing to cancer promotion and its metastasization. Platelets and MPs can play an indirect role in the metastatic process by helping malignant cells to escape from immunological surveillance. Furthermore, platelets and their derived MPs represent a potential source for blood biomarker development in oncology. This review provides an updated overview of the roles played by platelets and MPs in cancer and metastasis formation. The possible analysis of platelet and MP molecular signatures for the detection of cancer and monitoring of anticancer treatments is discussed. Finally, the potential use of MPs as vectors for drug delivery systems to cancer cells is put forward.

A novel mechanism for the anticancer activity of aspirin and salicylates

Epidemiological studies indicate that long‑term aspirin usage reduces the incidence of colorectal cancer (CRC) and may protect against other non‑CRC associated adenocarcinomas, including oesophageal cancer. A number of hypotheses have been proposed with respect to the molecular action of aspirin and other non‑steroidal anti‑inflammatory drugs in cancer development. The mechanism by which aspirin exhibits toxicity to CRC has been previously investigated by synthesising novel analogues and derivatives of aspirin in an effort to identify functionally significant moieties. Herein, an early effect of aspirin and aspirin‑like analogues against the SW480 CRC cell line was investigated, with a particular focus on critical molecules in the epidermal growth factor (EGF) pathway. The present authors proposed that aspirin, diaspirin and analogues, and diflunisal (a salicylic acid derivative) may rapidly perturb EGF and EGF receptor (EGFR) internalisation. Upon longer incubations, the diaspirins and thioaspirins may inhibit EGFR phosphorylation at Tyr1045 and Tyr1173. It was additionally demonstrated, using a qualitative approach, that EGF internalisation in the SW480 cell line may be directed to endosomes by fumaryldiaspirin using early endosome antigen 1 as an early endosomal marker and that EGF internalisation may also be perturbed in oesophageal cell lines, suggestive of an effect not only restricted to CRC cells. Taken together and in light of our previous findings that the aspirin‑like analogues can affect cyclin D1 expression and nuclear factor‑κB localisation, it was hypothesized that aspirin and aspirin analogues significantly and swiftly perturb the EGFR axis and that the protective activity of aspirin may in part be explained by perturbed EGFR internalisation and activation. These findings may also have implications in understanding the inhibitory effect of aspirin and salicylates on wound healing, given the critical role of EGF in the response to tissue trauma.

Advances in antitumor effects of NSAIDs

In recent years, the reports on using nonsteroidal anti-inflammatory drugs (NSAIDs) for cancer prevention and treatment have been on the rise. In 2017, the US Preventive Services Working Group issued primary prevention guidelines on the use of NSAIDs, especially aspirin, for cardiovascular disease and colorectal cancer, and formally established the role and status of aspirin in cancer prevention. However, the mechanism of NSAIDs on preventing cancer is still not clear. In this paper, the progress of the application of NSAIDs, especially aspirin, in the prevention and treatment of tumors in recent years is summarized, and new ideas and directions for the follow-up study are also discussed.

Aspirin, platelet inhibition and cancer prevention

Several lines of evidence are consistent with the hypothesis that activated platelets contribute to colorectal tumorigenesis and metastatization through direct cell-cell interactions and the release of different lipid and protein mediators, and microvesicles. This review examines the clinical pharmacology of low-dose aspirin as a basis for discussing the mechanisms underlying the contribution of platelets to neoplastic transformation and progression of cancer via the development of metastases.

Cyclooxygenase and lipoxygenase gene expression in the inflammogenesis of breast cancer

We examined the expression of major inflammatory genes, cyclooxygenase-1 and 2 (COX1, COX2) and arachidonate 5-lipoxygenase (ALOX5) in 1090 tumor samples of invasive breast cancer from The Cancer Genome Atlas (TCGA). Mean cyclooxygenase expression (COX1 + COX2) ranked in the upper 99th percentile of all 20,531 genes and surprisingly, the mean expression of COX1 was more than tenfold higher than COX2. Highly significant correlations were observed between COX2 with eight tumor-promoting genes (EGR2, IL6, RGS2, B3GNT5, SGK1, SLC2A3, SFRP1 and ETS2) and between ALOX5 and ten tumor promoter genes (CD33, MYOF1, NLRP1, GAB3, CD4, IFR8, CYTH4, BTK, FGR, CD37). Expression of CYP19A1 (aromatase) was significantly correlated with COX2, but only in tumors positive for ER, PR and HER2. Tumor-promoting genes correlated with the expression of COX1, COX2, and ALOX5 are known to effectively increase mitogenesis, mutagenesis, angiogenesis, cell survival, immunosuppression and metastasis in the pathogenesis of breast cancer.

Prevention of colonic neoplasia with polyethylene glycol: A short term randomized placebo-controlled double-blinded trial

Chemoprevention represents an attractive modality against colorectal cancer (CRC) although widespread clinical implementation of promising agents (e.g. aspirin/NSAIDS) have been stymied by both suboptimal efficacy and concerns over toxicity. This highlights the need for better agents. Several groups, including our own, have reported that the over-the-counter laxative polyethylene glycol (PEG) has remarkable efficacy in rodent models of colon carcinogenesis. In this study, we undertook the first randomized human trial to address the role of PEG in prevention of human colonic neoplasia. This was a double-blind, placebo-controlled, three-arm trial where eligible subjects were randomized to 8g PEG-3350 (n = 27) or 17g PEG-3350 (n = 24), or placebo (n = 24; maltodextrin) orally for a duration of six months. Our initial primary endpoint was rectal aberrant crypt foci (ACF) but this was changed during protocol period to rectal mucosal epidermal growth factor receptor (EGFR). Of the 87 patients randomized, 48 completed study primary endpoints and rectal EGFR unchanged PEG treatment. Rectal ACF had a trend suggesting potentially reduction with PEG treatment (pre-post change 1.7 in placebo versus -0.3 in PEG 8+ 17g doses, p = 0.108). Other endpoints (proliferation, apoptosis, expression of SNAIL and E-cadherin), previously noted to be modulated in rodent models, appeared unchanged with PEG treatment in this clinical trial. We conclude that PEG was generally well tolerated with the trial failing to meet primary efficacy endpoints. However, rectal ACFs demonstrated a trend (albeit statistically insignificant) for suppression with PEG. Moreover, all molecular assays including EGFR were unaltered with PEG underscoring issues with lack of translatability of biomarkers from preclinical to clinical trials. This data may provide the impetus for future clinical trials on PEG using more robust biomarkers of chemoprevention.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00828984.

Association analysis of ILVBL gene polymorphisms with aspirin-exacerbated respiratory disease in asthma

Background

We previously reported that the ILVBL gene on chromosome 19p13.1 was associated with the risk for aspirin-exacerbated respiratory disease (AERD) and the percent decline of forced expired volume in one second (FEV1) after an oral aspirin challenge test. In this study, we confirmed the association between polymorphisms and haplotypes of the ILVBL gene and the risk for AERD and its phenotype.

Methods

We recruited 141 AERD and 995 aspirin-tolerant asthmatic (ATA) subjects. All study subjects underwent an oral aspirin challenge (OAC). Nine single nucleotide polymorphisms (SNPs) with minor allele frequencies above 0.05, which were present in the region from 2 kb upstream to 0.5 kb downstream of ILVBL in Asian populations, were selected and genotyped.

Results

In an allelic association analysis, seven of nine SNPs were significantly associated with the risk for AERD after correction for multiple comparisons. In a codominant model, the five SNPs making up block2 (rs2240299, rs7507755, rs1468198, rs2074261, and rs13301) showed significant associations with the risk for AERD (corrected P = 0.001–0.004, OR = 0.59–0.64). Rs1468198 was also significantly associated with the percent decline in FEV1 in OAC tests after correction for multiple comparisons in the codominant model (corrected P = 0.033), but the other four SNPs in hapblock2 were not.

Conclusion

To the best of our knowledge, this is the first report of an association between SNPs on ILVBL and AERD. SNPs on ILVBL could be promising genetic markers of this condition.

Electronic supplementary material

The online version of this article (10.1186/s12890-017-0556-6) contains supplementary material, which is available to authorized users.

Colorectal Cancer Cell Line Proteomes Are Representative of Primary Tumors and Predict Drug Sensitivity

BACKGROUND AND AIMS

Proteomics holds promise for individualizing cancer treatment. We analyzed to what extent the proteomic landscape of human colorectal cancer (CRC) is maintained in established CRC cell lines and the utility of proteomics for predicting therapeutic responses.

METHODS

Proteomic and transcriptomic analyses were performed on 44 CRC cell lines, compared against primary CRCs (n=95) and normal tissues (n=60), and integrated with genomic and drug sensitivity data.

RESULTS

Cell lines mirrored the proteomic aberrations of primary tumors, in particular for intrinsic programs. Tumor relationships of protein expression with DNA copy number aberrations and signatures of post-transcriptional regulation were recapitulated in cell lines. The 5 proteomic subtypes previously identified in tumors were represented among cell lines. Nonetheless, systematic differences between cell line and tumor proteomes were apparent, attributable to stroma, extrinsic signaling, and growth conditions. Contribution of tumor stroma obscured signatures of DNA mismatch repair identified in cell lines with a hypermutation phenotype. Global proteomic data showed improved utility for predicting both known drug-target relationships and overall drug sensitivity as compared with genomic or transcriptomic measurements. Inhibition of targetable proteins associated with drug responses further identified corresponding synergistic or antagonistic drug combinations. Our data provide evidence for CRC proteomic subtype-specific drug responses.

CONCLUSIONS

Proteomes of established CRC cell line are representative of primary tumors. Proteomic data tend to exhibit improved prediction of drug sensitivity as compared with genomic and transcriptomic profiles. Our integrative proteogenomic analysis highlights the potential of proteome profiling to inform personalized cancer medicine.

A Small Molecule Inhibitor of the β-Catenin-TCF4 Interaction Suppresses Colorectal Cancer Growth In Vitro and In Vivo

Colorectal cancer is associated with aberrant activation of the Wnt pathway. β-Catenin plays essential roles in the Wnt pathway by interacting with T-cell factor 4 (TCF4) to transcribe oncogenes. We synthesized a small molecule, referred to as HI-B1, and evaluated signaling changes and biological consequences induced by the compound. HI-B1 inhibited β-catenin/TCF4 luciferase activity and preferentially caused apoptosis of cancer cells in which the survival is dependent on β-catenin. The formation of the β-catenin/TCF4 complex was disrupted by HI-B1 due to the direct interaction of HI-B1 with β-catenin. Colon cancer patient-derived xenograft (PDX) studies showed that a tumor with higher levels of β-catenin expression was more sensitive to HI-B1 treatment, compared to a tumor with lower expression levels of β-catenin. The different sensitivities of PDX tumors to HI-B1 were dependent on the β-catenin expression level and potentially could be further exploited for biomarker development and therapeutic applications against colon cancer.

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HI-B1 is a synthesized compound identified as a β-catenin inhibitor suppressing the β-catenin-TCF4 protein interaction.

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HI-B1 preferentially causes apoptosis in β-catenin-dependent cancer cells.

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A colon cancer PDX mouse model with a high level of β-catenin is sensitive to HI-B1.

β-catenin is an important protein that facilitates colon cancer. Shin et al. synthesized and identified HI-B1 as a direct β-catenin inhibitor. HI-B1 disrupted formation of the β-catenin-TCF4 protein complex. HI-B1 preferentially caused apoptosis of cancer cells in which the survival is dependent on β-catenin. In a comparison of two colon cancer PDX models with different β-catenin levels, they showed that β-catenin-high PDX is more sensitive to HI-B1 treatment than β-catenin-low PDX. HI-B1 could thus be further developed as a colon cancer drug, and β-catenin expression levels might be a predictive biomarker for colon cancer therapy using β-catenin inhibitors.

Finding New Tricks for Old Drugs: Tumoricidal Activity of Non-Traditional Antitumor Drugs

Chemotherapy, a traditional method, plays an important role in tumor therapy. Currently, common clinical antitumor drugs have several defects like poor efficacy, side effects, etc. Furthermore, developing new antitumor drugs takes a long time and requires many resources. Recent studies have found that oldies are newbies for the oncologist, such as flavonoid, metformin, aspirin, etc. These non-traditional antitumor drugs (NTADs) are widely used in management of non-cancer diseases, which gained FDA approval for treatment of patients. Increasingly, studies about antitumor action of NTADs have attracted many researchers' interests. A giant amount of studies showed a decrease in cancer incidence in NTAD-treated patients. Several reports outlined a direct inhibitory effect of NTADs on cancer cell growth and antitumoral actions. This review summarized the research progress on antitumor effects of ten NTADs. Retrospective and meta-analyses of trials also showed that these NTADs had preventive effects against cancer in vitro and in vivo. These drugs represent a promising option for cancer treatment, which have clear benefits including clinical safety, obvious curative effect, and saving medical and health resources. Judged from previous reports, future studies will yield valuable data about the profitable effects of these drugs. With a better understanding of its mechanisms of antitumor activity, NTADs may become available for combination with chemotherapy or targeted therapy in clinic.

Repositioning of drugs for intervention in tumor progression and metastasis: Old drugs for new targets

The increasing unraveling of the molecular basis of cancer offers manifold novel options for intervention strategies. However, the discovery and development of new drugs for potential clinical applications is a tremendously time-consuming and costly process. Translating a novel lead candidate compound into an approved clinical drug takes often more than a decade, and the success rate is very low due to versatile efforts including defining its pharmacokinetics, pharmacodynamics, side effects as well as lack of sufficient efficacy. Thus, strategies are needed to minimize time and costs, while maximizing success rates. A very attractive strategy for novel cancer therapeutic options is the repositioning of already approved drugs. These medicines, approved for the treatment of non-malignant disorders, have already passed some early costs and time, have been tested in humans and are ready for clinical trials as anti-cancer drugs. Here we discuss the repositioning of nonsteroidal anti-inflammatory drugs (NSAID), statins, anti-psychotic drugs, anti-helminthic drugs and vitamin D as anti-tumor agents. We focus on their novel actions and potential for inhibition of cancer growth and metastasis by interfering with target molecules and pathways, which drive these malignant processes. Furthermore, important pre-clinical and clinical data are reviewed herein, which elucidate their therapeutic mechanisms which enable their repositioning for cancer therapy and disruption of metastasis.