BackgroundThe association of waterpipe tobacco (WPT) smoking with gastric cancer (GC) risk was suggested.MethodsA hospital-based case-control study was conducted to examine the association of WPT with GC risk among Vietnamese men, in Hanoi city, during the period of 2003–2011. Newly-diagnosed GC cases (n = 454) and control patients (n = 628) were matched by age (+/- 5 years) and the year of hospitalization. Information on smoking and alcohol drinking habits and diet including salty food intake and fruits/vegetables consumption were obtained by the interview. Maximum likelihood estimates of odds ratios (ORs) and corresponding 95% confidence intervals (Cis) were obtained using conditional logistic regression models.ResultsThe group with the highest consumption of citrus fruits showed a significantly low GC risk (OR = 0.6, 95%CI = 0.4–0.8, P for trend = 0.002). However, there was no association of raw vegetable consumption with GC risk. Referring to never smokers, GC risk was significantly higher in current WPT smokers (OR = 1.8, 95%CI = 1.3–2.4), and it was more evident in exclusively WPT smokers (OR = 2.7, 95%CI = 1.2–6.5). GC risk tended to be higher with daily frequency and longer duration of WPT smoking but these trends were not statistically significant (P for trend: 0.144 and 0.154, respectively). GC risk of those who started smoking WPT before the age of 25 was also significantly high (OR = 3.7, 95%CI = 1.2–11.3). Neither cigarette smoking nor alcohol drinking was related to GC risk.ConclusionThe present findings revealed that WPT smoking was positively associated with GC risk in Vietnamese men.

BackgroundFrom among a cohort of 65,553 men aged 30–84 in Karunagappally Taluk, Kerala, India, 52 hypopharyngeal cancer cases and 85 laryngeal cancer cases were identified by the Karunagappally Cancer Registry during the period between 1990 and 2009.MethodsWe conduct Poisson regression analysis of grouped data, taking into account age and education.ResultsThis study showed that the incidence rates of cancers of the hypopharynx and the larynx were strongly related to the number of bidis smoked a day (P<0.001 for both hypopharyngeal and laryngeal cancers) and duration of bidi smoking (P=0.009; P<0.001). Laryngeal cancer risk was significantly increased by bidi smoking (P<0.001), cigarette smoking (P=0.013) and regular alcohol use (P=0.005).ConclusionThe present study, the first cohort study to examine the association of hypopharyngeal and laryngeal cancer incidence rates with bidi smoking in South Asia, clearly showed dose–response relationships between those cancer risks and bidi smoking; larger amounts of bidi smoked a day and longer durations of bidi smoking increased the incidence rates of those cancers. Tobacco chewing was found not related to the risk of hypopharynx or larynx cancer.

Summary In the first Rural Cancer Registry in India, 194 cervical cancer cases were registered during . The 3 year survival was significantly higher in cases registered in 1990-91 (44.0%), than in those registered in the earlier years (26.6%). This improvement was due to the cancer education activities undertaken by the Registry.

Among a male cohort in South India, gastric cancer risk increased with the number and duration of bidi smoking.

BackgroundThe aim of this study is to examine the inflammatory-cytokine expressions in the presence of non-cytotoxic dose of methylmercury (MeHg) in murine macrophages, which is suspected to play an important role in brain damage caused by MeHg exposure. We focused on murine macrophage inflammatory protein-2 (MIP-2), keratinocyte chemoattractant (KC), and monocyte chemoattractant protein-5 (MCP-5). MIP-2 and KC are murine functional homologues of human IL-8 and MCP-5 for human MCP-1. Furthermore, we examined the suppressive effect of N-acetyl-l-cysteine (NAC) on the MeHg-induced inflammatory cytokines.MethodsIn a murine RAW264.7 macrophage cell line, MeHg-induced cytokine expressions were measured using real-time PCR. The suppressive effect of NAC was examined by putting it into the culture medium together with MeHg (co-treatment). In addition, pre- and post-treatment experiments were conducted, in which the cells were treated with NAC before and after MeHg exposure, respectively.ResultsExposure to a non-cytotoxic dose of MeHg up-regulated the mRNA expression of MIP-2 and MCP-5. On the other hand, KC expression was not induced in the presence of MeHg. Effect of MeHg on MIP-2 expressions was suppressed by pre-, co-, and post-treatment with NAC. However, the suppressive effect of pre-treatment was less than the post-treatment, which was as effective as co-treatment.ConclusionIn functional homologues of human IL-8, only MIP-2 expression, not KC, was activated in the presence of non-cytotoxic dose of MeHg in murine RAW264.7 macrophage cell line. The more evident inhibitory effect of NAC observed in post-treatment experiments suggests a possible involvement of intracellular activities such as antioxidant effects.

No abstract

Epstein-Barr virus (EBV) infection in tumor cells is usually restricted to the latent form, indicating that the induction of viral lytic infection may present a novel approach for the treatment of EBV‑associated tumors. By contrast, EBV lytic replication is inhibited by high‑levels of nuclear factor (NF)‑κB, which suggests that NF‑κB inhibitors may activate lytic replication from the latent form. In the current study, the addition of NF‑κB inhibitors (Bay11‑7082, Z‑LLF‑CHO and aspirin) was observed to induce the EBV lytic genes BZLF1, BRLF1 and BMRF1 in EBV‑positive gastric cancer (GC) cells. Both EBV‑positive and ‑negative GC cells were treated with different concentrations of anti‑herpes agents and the cytotoxic effects were measured at different time points following induction of EBV lytic replication. A marginal dose‑ and time‑dependent reduction in cell viability was observed for EBV‑positive and‑negative GC cells. The cytotoxic effects of NF‑κB inhibitors on EBV‑positive GC cells were enhanced by the addition of the anti‑herpes agents, ganciclovir, acyclovir, foscarnet and brivudine (P<0.05). However, there was no significant synergistic effect on EBV‑negative GC cells. The combination of 5 mM aspirin and ganciclovir exhibited the highest cytotoxic effect in EBV‑positive GC cells (CC50=7.2 µg/ml).

Epstein–Barr virus, a ubiquitous human herpes virus with oncogenic activity, can be found in 6%–16% of gastric carcinomas worldwide. In Epstein–Barr virus–associated gastric carcinoma, only a few latent genes of the virus are expressed. Ionizing irradiation was shown to induce lytic Epstein–Barr virus infection in lymphoblastoid cell lines with latent Epstein–Barr virus infection. In this study, we examined the effect of ionizing radiation on the Epstein–Barr virus reactivation in a gastric epithelial cancer cell line (SNU-719, an Epstein–Barr virus–associated gastric carcinoma cell line). Irradiation with X-ray (dose = 5 and 10 Gy; dose rate = 0.5398 Gy/min) killed approximately 25% and 50% of cultured SNU-719 cells, respectively, in 48 h. Ionizing radiation increased the messenger RNA expression of immediate early Epstein–Barr virus lytic genes (BZLF1 and BRLF1), determined by real-time reverse transcription polymerase chain reaction, in a dose-dependent manner at 48 h and, to a slightly lesser extent, at 72 h after irradiation. Similar findings were observed for other Epstein–Barr virus lytic genes (BMRF1, BLLF1, and BcLF1). After radiation, the expression of transforming growth factor beta 1 messenger RNA increased and reached a peak in 12–24 h, and the high-level expression of the Epstein–Barr virus immediate early genes can convert latent Epstein–Barr virus infection into the lytic form and result in the release of infectious Epstein–Barr virus. To conclude, Ionizing radiation activates lytic Epstein–Barr virus gene expression in the SNU-719 cell line mainly through nuclear factor kappaB activation. We made a brief review of literature to explore underlying mechanism involved in transforming growth factor beta–induced Epstein–Barr virus reactivation. A possible involvement of nuclear factor kappaB was hypothesized.