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Contrary to many reports that antiplatelet agents inhibit cancer growth and metastasis, new solid tumors have been reported in patients receiving long-term antiplatelet therapy. We investigated the effects of these agents directly on cancer cells in the absence of platelets to mimic the effects of long-term therapy. When four antiplatelet agents (aspirin, clopidogrel, prasugrel, and ticagrelor) were administered to colon cancer cells, cancer cell proliferation was inhibited similarly to a previous study. However, surprisingly, when cells were treated with a purinergic P2Y12 inhibitor (purinergic antiplatelet agent), the motility of the cancer cells was significantly increased. Therefore, gene expression profiles were identified to investigate the effect of P2Y12 inhibitors on cell mobility, and Serpin family 1 (SERPINE1) was identified as a common gene associated with cell migration and cell death in three groups. Antiplatelet treatment increased the level of SERPINE1 in cancer cells and also promoted the secretion of SERPINE1 into the medium. Increased SERPINE1 was found to induce MMP1 and, thus, increase cell motility. In addition, an increase in SERPINE1 was confirmed using the serum of patients who received these antiplatelet drugs. With these results, we propose that SERPINE1 could be used as a new target gene to prevent the onset and metastasis of cancer in patients with long-term antiplatelet therapy.

Previously, we identified eight novel minisatellites in the MUC2, of which allelic variants in MUC2-MS6 were examined to influence susceptibility to gastric cancer. However, studies on the susceptibility to gastrointestinal cancer of other minisatellites in the MUC2 region still remain unprogressive.In this study, we investigated whether polymorphic variations in the MUC2-MS8 region are related to susceptibility to gastrointestinal cancer.We assessed the association between MUC2-MS8 and gastrointestinal cancers by a case-control study with 1229 controls, 486 gastric cancer cases, 220 colon cancer cases and 278 rectal cancer cases. To investigate whether intronic minisatellites affect gene expression, various minisatellites were inserted into the luciferase-reporter vector and their expression levels were examined. We also examined the length of MUC2-MS8 alleles in blood and cancer tissue matching samples of 107 gastric cancer patients, 125 colon cancer patients, and 85 rectal cancer patients, and investigated whether the repeat sequence affects genome instability.A statistically significant association was identified between rare MUC2-MS8 alleles and the occurrence of rectal cancer: odds ratio (OR), 6.66; 95% confidence interval (CI), 1.11-39.96; and P = 0.0165. In the younger group (age, 55), rare alleles were significant associated with an increased risk of rectal cancer (odds ratio, 24.93 and P = 0.0001). Suppression of expression was found in the reporter vector inserted with minisatellites, and loss of heterozygosity (LOH) of the MUC2-MS8 region was confirmed in cancer tissues of gastrointestinal cancer patients (0.8-5.9%).Our results suggest that the rare alleles of MUC2-MS8 could be used to identify the risk of rectal cancer and that this repeat region is related to genomic instability.

DNA repair defects are important factors in cancer development. High DNA repair activity can affect cancer progression and chemoresistance. DNA double-strand breaks in cancer cells caused by anticancer agents can be restored by non-homologous end joining (NHEJ) and homologous recombination repair (HRR). Our previous study has identified E2F1 as a key gene in bladder cancer progression. In this study, DNA repair genes related to E2F1 were analyzed, and RAD54L involved in HRR was identified. In gene expression analysis of bladder cancer patients, the survival of patients with high RAD54L expression was shorter with cancer progression than in patients with low RAD54L expression. This study also revealed that E2F1 directly binds to the promoter region of RAD54L and regulates the transcription of RAD54L related to the HRR pathway. This study also confirmed that DNA breaks are repaired by RAD54L induced by E2F1 in bladder cancer cells treated with MMC. In summary, RAD54L was identified as a new target directly regulated by E2F1. Our results suggest that, E2F1 and RAD54L could be used as diagnostic markers for bladder cancer progression and represent potential therapeutic targets.

hTERT contains a high density of minisatellites, of which rare alleles of hTERT-VNTR2-2A case-control study was performed using DNA from 818 cancer-free controls, 539 cases with gastric cancer, 275 cases with colon cancer and 274 cases with rectal cancer. To determine whether minisatellites affect gene expression, expression levels were examined using TERT-reporter vectors in cell lines. In addition, the length of the hTERT-VNTR2-2No statistically significant association between hTERT-VNTR2-2We suggest that minisatellites are associated with genomic instability in cancer and that the hTERT-VNTRs region may increase hTERT expression in gastrointestinal cancer cells.

Chronic inflammation, increased reactivity to self-antigens and incidences of cancer are hallmarks of aging.However, the underlying mechanisms are not well understood. Age-associated alterations in the DNA either due tooxidative damage, defects in DNA repair or epigenetic modifications such as methylation that lead to mutations andchanges in the expression of genes are thought to be partially responsible. Here we report that epigenetic modifications inaged DNA also increase its immunogenicity rendering it more reactive to innate immune system cells such as the dendriticcells. We observed increased upregulation of costimulatory molecules as well as enhanced secretion of IFN-α fromdendritic cells in response to DNA from aged donors as compared to DNA from young donors when it was deliveredintracellularly via Lipofectamine. Investigations into the mechanisms revealed that DNA from aged subjects is notdegraded, neither is it more damaged compared to DNA from young subjects. However, there is significantly decreasedglobal level of methylation suggesting that age-associated hypomethylation of the DNA may be the cause of its increasedimmunogenicity. Increased immunogenicity of self DNA may thus be another mechanism that may contribute to theincrease in age-associated chronic inflammation, autoimmunity and cancer. © Agrawal et al.