Search PubMed⌕ Search

Biomedical subjects

Yu-Peng Liu

Publications and source records attributed to Yu-Peng Liu.

8 recordsLinked to original sources

Integrative Transcriptomic and Proteomic Profiling Identifies S100P as a Potential Functional Biomarker for Sessile Serrated Lesions.

BACKGROUND: Sessile serrated lesions (SSLs) account for 15% of colorectal cancers (CRCs) but detection remains difficult due to flat morphology, mucinous features, and subtle histology. AIMS: This study aimed to identify novel and functionally relevant biomarkers of SSLs using transcriptomic screening and multi-omics validation. METHODS: Paired SSL and normal mucosa specimens (n = 6) underwent RNA sequencing. Differentially expressed genes (DEGs) were filtered for membrane or secretory proteins and validated across TCGA and adenoma transcriptomes. Functional significance was assessed using CRISPR dependency profiling, proteotranscriptomic concordance, pharmacogenomic sensitivity, and connectivity map analysis. RESULTS: We identified 216 upregulated genes in SSLs, including 68 encoding secretory/membrane proteins that better discriminated SSLs from controls and were enriched for adhesion and neuronal signaling while suppressing TNFα-NFκB inflammatory pathways. Cross-cohort comparison revealed five overlapping candidates between SSLs and TCGA CMS1 tumors. Among them, S100P emerged as the primary biomarker candidate, showing consistent upregulation in SSLs and CMS1 tumors while remaining low in normal mucosa and conventional adenomas. TFF1 also showed RNA-level upregulation but appeared more context-dependent. S100P demonstrated strong RNA-protein concordance in CRC cell-line profiling, supporting its detectability as a biomarker candidate. Pharmacogenomic profiling of LS411N cells revealed marked sensitivity to SN-38 and fluoropyrimidines, consistent with serrated CRC vulnerabilities. Connectivity map analysis identified perturbations, including MAPK1 and histone acetyltransferase suppression, that may reverse parts of the SSL transcriptional program. CONCLUSION: These findings prioritize S100P as a promising biomarker candidate for SSLs that warrants further validation in larger cohorts and clinically applicable platforms.

Humans↗

TNF-alpha/IFN-gamma-induced iNOS expression increased by prostaglandin E2 in rat primary astrocytes via EP2-evoked cAMP/PKA and intracellular calcium signaling.

Astrocytes, the most abundant glia in the central nervous system (CNS), produce a large amount of prostaglandin E(2) (PGE(2)) in response to proinflammatory mediators after CNS injury. However, it is unclear whether PGE(2) has a regulatory role in astrocytic activity under the inflamed condition. In the present work, we showed that PGE(2) increased inducible nitric oxide synthase (iNOS) production by tumor necrosis factor-alpha and interferon-gamma (T/I) in astrocytes. Pharmacological and RNA interference approaches further indicated the involvement of the receptor EP2 in PGE(2)-induced iNOS upregulation in T/I-treated astrocytes. Quantitative real-time polymerase chain reaction and gel mobility shift assays also demonstrated that PGE(2) increased iNOS transcription through EP2-induced cAMP/protein kinase A (PKA)-dependent pathway. Consistently, the effect of EP2 was significantly attenuated by the PKA inhibitor KT-5720 and partially suppressed by the inhibitor (SB203580) of p38 mitogen-activated protein kinase (p38MAPK), which serves as one of the downstream components of the PKA-dependent pathway. Interestingly, EP2-mediated PKA signaling appeared to increase intracellular Ca(2+) release through inositol triphosphate (IP3) receptor activation, which might in turn stimulate protein kinase C (PKC) activation to promote iNOS production in T/I-primed astrocytes. By analyzing the expression of astrocytic glial fibrillary acidic protein (GFAP), we found that PGE(2) alone only triggered the EP2-induced cAMP/PKA/p38MAPK signaling pathway in astrocytes. Collectively, PGE(2) may enhance T/I-induced astrocytic activation by augmenting iNOS/NO production through EP2-mediated cross-talk between cAMP/PKA and IP3/Ca(2+) signaling pathways.

Animals↗

Tumor necrosis factor-alpha and interleukin-18 modulate neuronal cell fate in embryonic neural progenitor culture.

Neural progenitor cells (NPCs) in developing and adult CNS are capable of giving rise to various neuronal and glial cell populations. Neurogenesis in the adult hippocampus has been found to be inhibited by a proinflammatory cytokine, interleukin-6 (IL-6), suggesting that activated microglia in the inflamed brain may control neurogenesis. Yet, little is known about the effect of microglia-derived factors on the cell fate of embryonic NPCs. In this study, we show that neurons with betaIII-tubulin immunoreactivity in the NPC culture were reduced by the condition media collected from microglia treated with endotoxin lipopolysaccharide (LPS/M-CM). Treatment with pentoxifylline (PTX), an inhibitor for tumor necrosis factor-alpha (TNF-alpha) secretion from LPS-activated microglia, blocked the reduction of betaIII-tubulin+ cells in NPC culture. Furthermore, treatment of NPCs with interleukin-18 (IL-18), a recently discovered proinflammatory cytokine, also decreased the number of betaIII-tubulin+ cells in a dose- and time-dependent manner. Surprisingly, we also observed that the remaining betaIII-tubulin+ cells in the LPS/M-CM-treated culture exhibited more branching neurites. Thus, the activated microglia-derived cytokines, TNF-alpha and IL-18, may either inhibit the neuronal differentiation or induce neuronal cell death in the NPC culture, whereas these cells may also produce factors to improve the neurite branching in the NPC culture.

Animals↗