DNA and RNA sequencing analysis revealed alterations of ANK3, PKHD1 and olfactory transduction as potential biomarker of three-year survival in gastric cancer.

4034 Background: Gastric cancer is the third leading cause of cancer related death worldwide. Although targeted and immune therapy have brought new benefit for patients, it still faces challenges of limited effective group and survival. Here we investigate the association of overall survival with DNA and RNA alterations to explore potential biomarkers of prognosis in gastric cancer. Methods: Whole-exome sequencing, RNA sequencing and clinical data of 442 patients with stomach cancer were downloaded from TCGA. Clinical factors and mutational landscape (insertion/ deletion/ single nucleotide variant) were compared between group of OS3+ (overall survival > 3 years) and OS3- (OS < 3 years). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed based on differentially expressed RNAs between the two groups. Results: 415 of 442 patients with stage information were included. The corresponding rates of OS3+ for patients in stage of I/II/III/IV was 15.5% (9/58), 10.8% (9/58), 10.9% (9/58), 13.6% (9/58), respectively. When comparing the 49 patients with OS3+ to others with OS3-, no difference of stage or sex distribution was discovered, except that OS3+ group had lower median age at diagnosis than OS3- group (63 vs. 71 years, P = 0.029). Tumor mutation burden was comparable between groups. Mutational landscape showed that the two groups shared 70% of top 20 mutations. Among the 20 hot genes, mutations of ANK3(P = 0.006), PKHD1(P = 0.008) were more frequent in OS3+ group, Studies in breast and prostate cancer inferred that, ANK3 was involved in activity of androgen receptor signaling and cyclins, increased expression of ANK3 in cancer was probably associated with better survival. PKHD1 was involved in calcium ion binding and actin binding and was identified as a protective factor for colorectal cancer. OS3- group tend to have higher mutation frequency of HMCN1(P = 0.062). Previous reports showed that mutation of HMCN1 was enriched in peritoneal metastasis of gastric cancer, it might contribute to progression in gastric cancer. Enrichment analysis revealed difference between the two groups in olfactory transduction ( P < 0.01, KEGG analysis), neuroactive ligand-receptor interaction ( P < 0.05, KEGG analysis) and detection of chemical stimulus in sensory perception of smell ( P < 0.01, GO analysis). Numbers of discussions have inferred that genes involved in olfactory transduction may also participate in tumor cell proliferation, migration, and invasion. Conclusions: Patients with OS3+ was enriched with mutations of ANK3 and PKHD1 and present significant functional difference in olfactory transduction. These are potential biomarkers of better survival in gastric cancer. Further studies are needed to figure out their roles in tumor activity and provide insight for novel antitumor treatment development.

Transduction and Adaptation Mechanisms in the Cilium or Microvilli of Photoreceptors and Olfactory Receptors From Insects to Humans

Sensing changes in the environment is crucial for survival. Animals from invertebrates to vertebrates use both visual and olfactory stimuli to direct survival behaviors including identification of food sources, finding mates, and predator avoidance. In primary sensory neurons there are signal transduction mechanisms that convert chemical or light signals into an electrical response through ligand binding or photoactivation of a receptor, that can be propagated to the olfactory and visual centers of the brain to create a perception of the odor and visual landscapes surrounding us. The fundamental principles of olfactory and phototransduction pathways within vertebrates are somewhat analogous. Signal transduction in both systems takes place in the ciliary sub-compartments of the sensory cells and relies upon the activation of G protein-coupled receptors (GPCRs) to close cyclic nucleotide-gated (CNG) cation channels in photoreceptors to produce a hyperpolarization of the cell, or in olfactory sensory neurons open CNG channels to produce a depolarization. However, while invertebrate phototransduction also involves GPCRs, invertebrate photoreceptors can be either ciliary and/or microvillar with hyperpolarizing and depolarizing responses to light, respectively. Moreover, olfactory transduction in invertebrates may be a mixture of metabotropic G protein and ionotropic signaling pathways. This review will highlight differences of the visual and olfactory transduction mechanisms between vertebrates and invertebrates, focusing on the implications to the gain of the transduction processes, and how they are modulated to allow detection of small changes in odor concentration and light intensity over a wide range of background stimulus levels.

Bioinformatics Analysis in Different Expression Genes and Potential Pathways of CD4+ Cells in Childhood Allergic Asthma

Background: Asthma is one of the most common chronic respiratory diseases in children. CD4+T cell plays a key role in the immune response which affects the pathogenesis of asthma. Genetic level of CD4+T cells on childhood allergic asthma remains unclear. In our study, we aimed to identify potential different expressed genes (DEGs) and pathways related to childhood allergic asthma by performing bioinformatics analysis of dataset.Methods: GSE40887 dataset from Gene Expression Omnibus (GEO) was used for bioinformatics analysis. Limma package in R was used to detect DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were carried by Database for Annotation, Visualization and Integrated Discovery (DAVID). The construction of protein-protein interaction (PPI) network of the DEGs was performed by Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape. Hub genes were identified through cytoHubba in Cytoscape. Results: In all, 200 up-regulated genes and 69 down-regulated genes were identified. Up-regulated genes were mainly enriched in: protein self-association, cellular response to hydrogen peroxide, plasma membrane. As for down-regulated genes, enzyme binding and detection of chemical stimulus involved in sensory perception of smell, nucleolus were enriched. Only one KEGG pathway was enriched: olfactory transduction. In addition, top 10 hub genes were found including: PRPF19, CCAR1, CWC15, PRPF38A, PRCC, KRR1, RPS3, PDCD11, MKI67, and NUF2. Conclusion: Several DEGs (SNORD46, RPS3, OR5E1P, OR56A5 and OR51B6, and PDCD11), one pathway (olfactory transduction) and one biological process (cellular response to hydrogen peroxide) were found might associate to childhood allergic asthma. Our results may provide inspiration for other researchers on DEGs and pathways in CD4+T cells of childhood allergic asthma.

Expression pattern of olfactory receptor genes in human cumulus cells as an indicator for competent oocyte selection

Odorant or olfactory receptors are mainly localized in the olfactory epithelium for the perception of different odors. Interestingly, many ectopic olfactory receptors with low expression levels have recently been found in nonolfactory tissues to involve in local functions. Therefore, we investigated the probable role of the olfactory signaling pathway in the surrounding microenvironment of oocyte. This study included 22 women in intracytoplasmic sperm injection cycle. The expression of olfactory target molecules in cumulus cells surrounding the growing and mature oocytes was evaluated by Western blotting and real-time polymerase chain reaction. Additionally, integrated bioinformatics analyses were carried out and 6 ectopic olfactory receptors were selected for further evaluation. The initiation of olfactory transduction cascade in cumulus cells of competent oocytes was confirmed by analyzing the expression of adenylyl cyclase type 3 and olfactory market protein. Moreover, the expression pattern of the selected olfactory receptors was evaluated and OR10H2 was selected due to a high level of expression in mature fertile oocytes. We suggested that OR10H2 could be considered as a reliable biomarker for oocyte selection in assisted reproduction technique programs. However, further studies are required to elucidate the role of olfactory transduction cascade in embryo quality and implantation.

Inhibitory signaling in mammalian olfactory transduction potentially mediated by Gαo

Olfactory GPCRs (ORs) in mammalian olfactory receptor neurons (ORNs) mediate excitation through the Gαs family member Gαolf. Here we tentatively associate a second G protein, Gαo, with inhibitory signalling in mammalian olfactory transduction by first showing that odor evoked phosphoinositide 3-kinase (PI3K)-dependent inhibition of signal transduction is absent in the native ORNs of mice carrying a conditional OMP-Cre based knockout of Gαo. We then identify an OR from native rat ORNs that are activated by octanol through cyclic nucleotide signaling and inhibited by citral in a PI3K-dependent manner. We show that the OR activates cyclic nucleotide signaling and PI3K signaling in a manner that reflects its functionality in native ORNs. Our findings lay the groundwork to explore the interesting possibility that ORs can interact with two different G proteins in a functionally identified, ligand-dependent manner to mediate opponent signaling in mature mammalian ORNs.

Transcriptome sequencing of olfactory-related genes in olfactory transduction of large yellow croaker (Larimichthy crocea) in response to bile salts

Fish produce and release bile salts as chemical signalling substances that act as sensitive olfactory stimuli. To investigate how bile salts affect olfactory signal transduction in large yellow croaker (Larimichthy crocea), deep sequencing of olfactory epithelium was conducted to analyse olfactory-related genes in olfactory transduction. Sodium cholates (SAS) have typical bile salt chemical structures, hence we used four different concentrations of SAS to stimulate L. crocea, and the fish displayed a significant behavioural preference for 0.30% SAS. We then sequenced olfactory epithelium tissues, and identified 9938 unigenes that were significantly differentially expressed between SAS-stimulated and control groups, including 9055 up-regulated and 883 down-regulated unigenes. Subsequent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses found eight categories linked to the olfactory transduction pathway that was highly enriched with some differentially expressed genes (DEGs), including the olfactory receptor (OR), Adenylate cyclase type 3 (ADCY3) and Calmodulin (CALM). Genes in these categories were analysed by RT-qPCR, which revealed aspects of the pathway transformation between odor detection, and recovery and adaptation. The results provide new insight into the effects of bile salt stimulation in olfactory molecular mechanisms in fishes, and expands our knowledge of olfactory transduction, and signal generation and decline.