Integration of metabolites from meta-analysis with transcriptome reveals enhanced SPHK1 in PDAC with a background of pancreatitis

• Published in: BMC cancer Vol. 22; no. 1; p. 792
• Main Authors: Ketavarapu, Vijayasarathy, Ravikanth, Vishnubhotla, Sasikala, Mitnala, Rao, G V, Devi, Ch Venkataramana, Sripadi, Prabhakar, Bethu, Murali Satyanarayana, Amanchy, Ramars, Murthy, H V V, Pandol, Stephen J, Reddy, D Nageshwar
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 19-07-2022; BioMed Central; BMC
• Subjects: Adenocarcinoma; Adenocarcinoma - pathology; Analysis; Bias; Biomarkers; Carcinoma, Pancreatic Ductal - pathology; Care and treatment; Chronic pancreatitis; Complications and side effects; Development and progression; Diagnosis; Gene expression; Gene mapping; Genetic transformation; Humans; Immunohistochemistry; Inflammation; Integration; Lipid metabolism; Medical prognosis; Meta-analysis; Metabolism; Metabolites; Metabolomic biomarkers; Ontology; Pancreas; Pancreatic cancer; Pancreatic ductal adenocarcinoma; Pancreatic Neoplasms; Pancreatic Neoplasms - pathology; Pancreatitis; Pancreatitis, Chronic - genetics; Patients; PDAC with background of CP; Quality standards; Risk factors; Software; Sphingomyelin; SPHK1; Statistical analysis; Systematic review; Therapeutic applications; Therapeutic targets; Transcriptome; Transcriptomes; Transcriptomics; Tricarboxylic acid cycle; United States; Metabolomic biomarkers; PDAC with background of CP; Transcriptomics; Chronic pancreatitis; Pancreatic ductal adenocarcinoma; SPHK1
• ISSN: 1471-2407; 1471-2407
• DOI: 10.1186/s12885-022-09816-6

Pathophysiology of transformation of inflammatory lesions in chronic pancreatitis (CP) to pancreatic ductal adenocarcinoma (PDAC) is not clear.
We conducted a systematic review, meta-analysis of circulating metabolites, integrated this data with transcriptome analysis of human pancreatic tissues and validated using immunohistochemistry. Our aim was to establish biomarker signatures for early malignant transformation in patients with underlying CP and identify therapeutic targets.
Analysis of 19 studies revealed AUC of 0.86 (95% CI 0.81-0.91, P < 0.0001) for all the altered metabolites (n = 88). Among them, lipids showed higher differentiating efficacy between PDAC and CP; P-value (< 0.0001). Pathway enrichment analysis identified sphingomyelin metabolism (impact value-0.29, FDR of 0.45) and TCA cycle (impact value-0.18, FDR of 0.06) to be prominent pathways in differentiating PDAC from CP. Mapping circulating metabolites to corresponding genes revealed 517 altered genes. Integration of these genes with transcriptome data of CP and PDAC with a background of CP (PDAC-CP) identified three upregulated genes; PIGC, PPIB, PKM and three downregulated genes; AZGP1, EGLN1, GNMT. Comparison of CP to PDAC-CP and PDAC-CP to PDAC identified upregulation of SPHK1, a known oncogene.
Our analysis suggests plausible role for SPHK1 in development of pancreatic adenocarcinoma in long standing CP patients. SPHK1 could be further explored as diagnostic and potential therapeutic target.