miR-1273h-5p suppresses CXCL12 expression and inhibits gastric cancer cell invasion and metastasis

Involvement of CXC chemokines (CXCL1-CXCL17) in gastric cancer: Prognosis and therapeutic molecules

Gastric cancer (GC) is the fifth-most prevalent and second-most deadly cancer worldwide. Due to the late onset of symptoms, GC is frequently treated at a mature stage. In order to improve the diagnostic and clinical decision-making processes, it is necessary to establish more specific and sensitive indicators valuable in the early detection of the disease whenever a cancer is asymptomatic. In this work, we gathered information about CXC chemokines and GC by using scientific search engines including Google Scholar, PubMed, SciFinder, and Web of Science. Researchers believe that GC chemokines, small proteins, class CXC chemokines, and chemokine receptors promote GC inflammation, initiation, and progression by facilitating angiogenesis, tumor transformation, invasion, survival, metastatic spread, host response safeguards, and inter-cell interaction. With our absolute best professionalism, the role of CXC chemokines and their respective receptors in GC diagnosis and prognosis has not been fully explained. This review article updates the general characteristics of CXC chemokines, their unique receptors, their function in the pathological process of GC, and their potential application as possible indicators for GC. Although there have only recently been a few studies focusing on the therapeutic efficacy of CXC chemokine inhibitors in GC, growing experimental evidence points to the inhibition of CXC chemokines as a promising targeted therapy. Therefore, further translational studies are warranted to determine whether specific antagonists or antibodies designed to target CXC chemokines alone or in combination with chemotherapy are useful for diagnosing advanced GC.

A state-of-art of underlying molecular mechanisms and pharmacological interventions/nanotherapeutics for cisplatin resistance in gastric cancer

The fourth common reason of death among patients is gastric cancer (GC) and it is a dominant tumor type in Ease Asia. One of the problems in GC therapy is chemoresistance. Cisplatin (CP) is a platinum compound that causes DNA damage in reducing tumor progression and viability of cancer cells. However, due to hyperactivation of drug efflux pumps, dysregulation of genes and interactions in tumor microenvironment, tumor cells can develop resistance to CP chemotherapy. The current review focuses on the CP resistance emergence in GC cells with emphasizing on molecular pathways, pharmacological compounds for reversing chemoresistance and the role of nanostructures. Changes in cell death mechanisms such as upregulation of pro-survival autophagy can prevent CP-mediated apoptosis that results in drug resistance. Moreover, increase in metastasis via EMT induction induces CP resistance. Dysregulation of molecular pathways such as PTEN, PI3K/Akt, Nrf2 and others result in changes in CP response of GC cells. Non-coding RNAs determine CP response of GC cells and application of pharmacological compounds with activity distinct of CP can result in sensitivity in tumor cells. Due to efficacy of exosomes in transferring bioactive molecules such as RNA and DNA molecules among GC cells, exosomes can also result in CP resistance. One of the newest progresses in overcoming CP resistance in GC is application of nanoplatforms for delivery of CP in GC therapy that they can increase accumulation of CP at tumor site and by suppressing carcinogenic factors and overcoming biological barriers, they increase CP toxicity on cancer cells.

PVT1/miR-16/CCND1 axis regulates gastric cancer progression

Long non-coding RNA plasmacytoma variant translocation 1 (PVT1) has been reported to be a vital modulator in tumorigenesis of gastric cancer (GC). However, the detailed regulatory mechanism of PVT1 in GC remains largely unclear. In this work, the expressions of PVT1 and microRNA-16 (miR-16) were detected by quantitative real-time PCR (qRT-PCR) in GC tissues and cell lines. GC cell lines NCI-N87 and MKN45 cell lines were chosen for the following assays. After PVT1 was overexpressed or depleted, CCK-8 and Transwell assays were performed to examine the cell viability and invasive capacity. Cell cycle was analyzed by flow cytometry. The expression of cyclin D1 (CCND1) at mRNA and protein levels was measured by qRT-PCR and western blot. The competitive endogenous RNA molecular mechanism among PVT1, miR-16 and CCND1 was verified by bioinformatics analysis, luciferase-reporter gene assay and RNA immunoprecipitation assay. In the present study, it was revealed that PVT1 expression was remarkably evaluated in GC tissues and cell lines than that in the corresponding control group. PVT1 positively regulated the proliferation, migration and cell cycle progression of GC cells. Besides, miR-16 was identified as a target of PVT1, and CCND1 was identified as a target of miR-16. The depletion of PVT1 promoted the expression of miR-16 and suppressed CCND1 expression. Moreover, either miR-16 inhibitor or CCND1 overexpression plasmid could reverse the promoting effects of PVT1 on the malignant biological behaviors of GC cells. In conclusion, PVT1 promoted CCND1 expression by negatively regulating miR-16 expression to enhance the viability, invasion and cell cycle progression of GC cells.

Oral Microbiota and Tumor-A New Perspective of Tumor Pathogenesis

Microorganisms have long been known to play key roles in the initiation and development of tumors. The oral microbiota and tumorigenesis have been linked in epidemiological research relating to molecular pathology. Notably, some bacteria can impact distal tumors by their gastrointestinal or blood-borne transmission under pathological circumstances. Certain bacteria drive tumorigenesis and progression through direct or indirect immune system actions. This review systemically discusses the recent advances in the field of oral microecology and tumor, including the oncogenic role of oral microbial abnormalities and various potential carcinogenesis mechanisms (excessive inflammatory response, host immunosuppression, anti-apoptotic activity, and carcinogen secretion) to introduce future directions for effective tumor prevention.