Co-expression modules construction by WGCNA and identify potential prognostic markers of uveal melanoma
EXPERIMENTAL EYE RESEARCH
Authors: Wan, Qi; Tang, Jing; Han, Yu; Wang, Dan
Abstract
Uveal melanoma is an aggressive cancer which has a high percentage recurrence and with a worse prognosis. Identify the potential prognostic markers of uveal melanoma may provide information for early detection of recurrence and treatment. RNA sequence data of uveal melanoma and patient clinic traits were obtained from The Cancer Genome Atlas (TCGA) database. Co-expression modules were built by weighted gene co-expression network analysis (WGCNA) and applied to investigate the relationship underlying modules and clinic traits. Besides, functional enrichment analysis was performed on these co-expression genes from interested modules. First, using WGCNA, identified 21 co-expression modules were constructed by the 10975 genes from the 80 human uveal melanoma samples. The number of genes in these modules ranged from 42 to 5091. Found four co-expression modules significantly correlated with three clinic traits (status, recurrence and recurrence Time). Module red, and purple positively correlated with patient's life status and recurrence Time. Module green positively correlates with recurrence. The result of functional enrichment analysis showed that the module magenta was mainly enriched genetic material assemble processes, the purple module was mainly enriched in tissue homeostasis and melanosome membrane and the module red was mainly enriched metastasis of cell, suggesting its critical role in the recurrence and development of the disease. Additionally, identified the hug gene (top connectivity with other genes) in each module. The hub gene SLC17A7, NTRK2, ABTB1 and ADPRHL1 might play a vital role in recurrence of uveal melanoma. Our findings provided the framework of co-expression gene modules of uveal melanoma and identified some prognostic markers might be detection of recurrence and treatment for uveal melanoma.
Identification of rat hippocampal mRNAs altered by the mitochondrial toxicant, 3-NPA
NEUROPROTECTIVE AGENTS
Authors: Przybyla-Zawislak, BD; Thorn, BT; Alia, SF; Dennis, RA; Amato, A; Virmani, A; Binienda, ZK
Abstract
3-Nitropropionic acid (3-NPA) is a model mitochondrial inhibitor that causes selective neurodegeneration in brain. 3-NPA-induced neurodegeneration occurs via a secondary neurotoxicity, caused initially by ATP depletion and redox changes in the cell. It is known that the hippocampal degeneration caused by mitochondrial dysfunction affects learning and memory, cognitive functions commonly disturbed in neurodegenerative diseases. The 3-NPA-treated animal model can be used to study molecular mechanisms underlying selective degeneration in the brain. In this study, a microarray approach was utilized to define changes in the expression of 530 genes in the rat hippocampus after acute exposure to 3-NPA at 30 mg/kg, sc. The microarray data were collected at 30 min, 2 h, and 4 h post-3-NPA. Statistical modeling using an ANOVA mixed model applied to Van der Waerden scores of rank-transformed intensity data was used to assign statistical significance to 44 transcripts. These transcripts represent genes associated with energy metabolism, calcium homeostasis, the cytoskeleton, neurotransmitter metabolism, and other cellular functions. Changes in the transcripts of genes encoding 2 transporters [blood-brain specific anion transporter (Slco1c1) and sodium-dependent inorganic phosphate cotransporter (Slc17a7)] were confirmed by real-time RT-PCR. In conclusion, this study identified 2 new potential targets for enhancement of neuroprotection or inhibition of neurodegeneration associated with ATP depletion in the hippocampus.