Predictive value of the serum RASSF10 promoter methylation status in gastric cancer

The Role of LMP1 in Epstein-Barr Virus-associated Gastric Cancer

EBV promotes many cancers such as lymphoma, nasopharyngeal carcinoma, and gastric; Latent Membrane Protein 1 (LMP1) is considered to be a major oncogenic protein encoded by Epstein- Barr virus (EBV). LMP1 functions as a carcinogen in lymphoma and nasopharyngeal carcinoma, and LMP1 may also promote gastric cancer. The expression level of LMP1 in host cells is a key determinant in tumorigenesis and maintenance of virus specificity. By promoting cell immortalization and cell transformation, promoting cell proliferation, affecting immunity, and regulating cell apoptosis, LMP1 plays a crucial tumorigenic role in epithelial cancers. However, very little is currently known about LMP1 in Epstein-Barr virus-associated gastric cancer (EBVaGC); the main reason is that the expression level of LMP1 in EBVaGC is comparatively lower than other EBV-encoded proteins, such as The Latent Membrane Protein 2A (LMP2A), Epstein-Barr nuclear antigen 1 (EBNA1) and BamHI-A rightward frame 1 (BARF1), to date, there are few studies related to LMP1 in EBVaGC. Recent studies have demonstrated that LMP1 promotes EBVaGC by affecting The phosphatidylinositol 3-kinase- Akt (PI3K-Akt), Nuclear factor-kappa B (NF-κB), and other signaling pathways to regulate many downstream targets such as Forkhead box class O (FOXO), C-X-C-motif chemokine receptor (CXCR), COX-2 (Cyclooxygenase-2); moreover, the gene methylation induced by LMP1 in EBVaGC has become one of the characteristics that distinguish this gastric cancer (GC) from other types of gastric cancer and LMP1 also promotes the formation of the tumor microenvironment (TME) of EBVaGC in several ways. This review synthesizes previous relevant literature, aiming to highlight the latest findings on the mechanism of action of LMP1 in EBVaGC, summarize the function of LMP1 in EBVaGC, lay the theoretical foundation for subsequent new research on LMP1 in EBVaGC, and contribute to the development of novel LMP1-targeted drugs.

New Advances in Nano-Drug Delivery Systems: Helicobacter pylori and Gastric Cancer

With the development of materials science and biomedicine, the application of nanomaterials in the medical field is further promoted. In the process of the diagnosis and treatment of diseases, a variety of drugs need to be used. It is an ideal state to make these drugs arrive at a specific location at a specific time and release at a specific speed, which can improve the bioavailability of drugs and reduce the adverse effects of drugs on normal tissues. Traditional drug delivery methods such as tablets, capsules, syrups, and ointments have certain limitations. The emergence of a new nano-drug delivery system further improves the accuracy of drug delivery and the efficacy of drugs. It is well known that the development of the cancer of the stomach is the most serious consequence for the infection of Helicobacter pylori. For the patients who are suffering from gastric cancer, the treatments are mainly surgery, chemotherapy, targeted and immune therapy, and other comprehensive treatments. Although great progress has been made, the diagnosis and prognosis of gastric cancer are still poor with patients usually diagnosed with cancer at an advanced stage. Current treatments are of limited benefits for patients, resulting in a poor 5-year survival rate. Nanomaterials may play a critical role in early diagnosis. A nano-drug delivery system can significantly improve the chemotherapy, targeted therapy, and immunotherapy of advanced gastric cancer, reduce the side effects of the original treatment plan and provide patients with better benefits. It is a promising treatment for gastric cancer. This article introduces the application of nanomaterials in the diagnosis and treatment of H. pylori and gastric cancer.

Relationship between DLEC1 and PBX3 promoter methylation and the risk and prognosis of gastric cancer in peripheral blood leukocytes

PURPOSE

Aberrant DNA methylation could regulate the expression of tumor suppressor gene DLEC1 and oncogene PBX3 and was related to the occurrence and prognosis of gastric cancer (GC). In this study, the associations between DLEC1 and PBX3 promoter methylation in peripheral blood leukocytes (PBLs) and the risk and prognosis of GC were investigated.

METHODS

The methylation status of DLEC1 and PBX3 promoter in PBLs of 368 GC cases and 382 controls was detected by the methylation-sensitive high-resolution melting (MS-HRM) method. Logistic and Cox regression were adopted to analyze the associations of DLEC1 and PBX3 methylation with GC risk and prognosis, respectively. Confounding biases were controlled by propensity score (PS).

RESULTS

Compared with negative methylation (Nm), DLEC1-positive methylation (Pm) was associated with increased GC risk in PS (OR 2.083, 95% CI 1.220-3.558, P = 0.007), but PBX3 Pm was not associated with GC risk. In the elderly group (≥ 60 years), DLEC1 Pm was associated with increased GC risk (OR 2.951, 95% CI 1.426-6.104, P = 0.004). The combined effects between DLEC1 methylation and consumption of dairy products, fried food intake and Helicobacter pylori (H. pylori) infection on GC risk were discovered (OR_c 3.461, 95% CI 1.847-6.486, P < 0.001, OR_c 3.246, 95% CI 1.708-6.170, P < 0.001 and OR_c 2.964, 95% CI 1.690-5.197, P < 0.001, respectively). Furthermore, DLEC1 and PBX3 methylation were not associated with GC prognosis.

CONCLUSION

DLEC1 methylation in PBLs and the combined effects of gene-environment can influence GC risk.