Ornithine decarboxylase (ODC1) gene variant (rs2302615) is associated with gastric cancer independently of Helicobacter pylori CagA serostatus

Pirin Promotes the Progression of Non-Small-Cell Lung Cancer by Increasing ODC1 to Suppress Autophagy

Non-small-cell lung cancer (NSCLC), a common malignant tumor, requires deeper pathogenesis investigation. Autophagy is an evolutionarily conserved lysosomal degradation process that is frequently blocked during cancer progression. It is an urgent need to determine the novel autophagy-associated regulators in NSCLC. Here, we found that pirin was upregulated in NSCLC, and its expression was positively correlated with poor prognosis. Overexpression of pirin inhibited autophagy and promoted NSCLC proliferation. We then performed data-independent acquisition-based quantitative proteomics to identify the differentially expressed proteins (DEPs) in pirin-overexpression (OE) or pirin-knockdown (KD) cells. Among the pirin-regulated DEPs, ornithine decarboxylase 1 (ODC1) was downregulated in pirin-KD cells while upregulated along with pirin overexpression. ODC1 depletion reversed the pirin-induced autophagy inhibition and pro-proliferation effect in A549 and H460 cells. Immunohistochemistry showed that ODC1 was highly expressed in NSCLC cancer tissues and positively related with pirin. Notably, NSCLC patients with pirinhigh/ODC1high had a higher risk in terms of overall survival. In summary, we identified pirin and ODC1 as a novel cluster of prognostic biomarkers for NSCLC and highlighted the potential oncogenic role of the pirin/ODC1/autophagy axis in this cancer type. Targeting this pathway represents a possible therapeutic approach to treat NSCLC.

Wood cookstove use is associated with gastric cancer in Central America and mediated by host genetics

Biomass cookstove food preparation is linked to aero-digestive cancers, mediated by ingested and inhaled carcinogens (e.g., heterocyclic amines, and polycyclic aromatic hydrocarbons). We investigated the association between gastric adenocarcinoma, wood cookstove use, H. pylori CagA infection and risk modification by variants in genes that metabolize and affect the internal dose of carcinogens. We conducted a population-based, case-control study (814 incident cases, 1049 controls) in rural Honduras, a high-incidence region with a homogeneous diet and endemic H. pylori infection, primarily with the high-risk CagA genotype. We investigated factors including wood cookstove use, H. pylori CagA serostatus, and 15 variants from 7 metabolizing genes, and the interactions between wood stove use and the genetic variants. Male sex (OR 2.0, 1.6-2.6), age (OR 1.04, 1.03-1.05), wood cookstove use (OR 2.3, 1.6-3.3), and CagA serostatus (OR 3.5, 2.4-5.1) and two SNPs in CYP1B1 (rs1800440 and rs1056836) were independently associated with gastric cancer in multivariate analysis. In the final multivariate model, a highly significant interaction (OR 3.1, 1.2-7.8) was noted between wood cookstove use and the rs1800440 metabolizing genotype, highlighting an important gene-environment interaction. Lifetime wood cookstove use associates with gastric cancer risk in the high-incidence regions of Central America, and the association is dependent on the rs1800440 genotype in CYP1B1. H. pylori CagA infection, wood cookstove use and the rs1800440 genotype, all of which are highly prevalent, informs who is at greatest risk from biomass cookstove use.

Helicobacter pylori infection causes both protective and deleterious effects in human health and disease

Infection with Helicobacter pylori (H. pylori) is necessary but not sufficient for the development of gastric cancer, the third leading cause of cancer death globally. H. pylori infection affects over half of people globally; however, it does not affect populations uniformly. H. pylori infection rates are declining in western industrialized countries but are plateauing in developing and newly industrialized countries where gastric cancer is most prevalent. Despite H. pylori infection being the primary causative agent for gastric cancer, H. pylori infection can also cause other effects, detrimental or beneficial, throughout an individual's life, with the beneficial effects often being seen in childhood and the deleterious effects in adulthood. H. pylori is an ancient bacterium and its likelihood of affecting disease or health is dependent on both human and bacterial genetics that have co-evolved over millennia. In this review, we focus on the impact of infection and its genetic bases in different populations and diseases throughout an individual's lifespan, highlighting the benefits of individualized treatment and argue that universal eradication of H. pylori in its host may cause more harm than good for those infected with H. pylori.