title: Protein pathway activation associated with sustained virologic response in patients with chronic hepatitis C treated with pegylated interferon (PEG-IFN) and ribavirin (RBV).
abstract: Only half of chronic hepatitis C (CH-C) patients treated with pegylated interferon and ribavirin (PEG-IFN+RBV) achieve sustained virologic response) SVR. In addition to known factors, we postulated that activation of key protein signaling networks in the peripheral blood mononuclear cells (PBMCs) may contribute to SVR due to inherent patient-specific basal immune cell signaling architecture. In this study, we included 92 patients with CH-C. PBMCs were collected while patients were not receiving treatment and used for phosphoprotein-based network profiling. Patients received a full course of PEG-IFN+RBV with overall SVR of 55%. From PBMC, protein lysates were extracted and then used for Reverse Phase Protein Microarray (RPMA) analysis, which quantitatively measured the levels of cytokines and activation levels of 25 key protein signaling molecules involved in immune cell regulation and interferon alpha signaling. Regression models for predicting SVR were generated by stepwise bidirectional selection. Both clinical-laboratory and RPMA parameters were used as predictor variables. Model accuracies were estimated using 10-fold cross-validation. Our results show that by comparing patients who achieved SVR to those who did not, phosphorylation levels of 6 proteins [AKT(T308), JAK1(Y1022/1023), p70 S6 Kinase (S371), PKC zeta/lambda(T410/403), TYK2(Y1054/1055), ZAP-70(Y319)/Syk(Y352)] and overall levels of 6 unmodified proteins [IL2, IL10, IL4, IL5, TNF-alpha, CD5L] were significantly different (P < 0.05). For SVR, the model based on a combination of clinical and proteome parameters was developed, with an AUC = 0.914, sensitivity of 92.16%, and specificity of 85.0%. This model included the following parameters: viral genotype, previous treatment status, BMI, phosphorylated states of STAT2, AKT, LCK, and TYK2 kinases as well as steady state levels of IL4, IL5, and TNF-alpha. In conclusion, SVR could be predicted by a combination of clinical, cytokine, and protein signaling activation profiles. Signaling events elucidated in the study may shed some light into molecular mechanisms of response to anti-HCV treatment.
authors.affiliation: Betty and Guy Beatty Center for Integrated Research, Inova Health System, Inova Fairfax Hospital, Falls Church, Virginia, 22042, USA. zobair.younossi@inova.org
authors.forename: Zobair M
authors.initials: ZM
authors.lastname: Younossi
authors.forename: Dolores
authors.initials: D
authors.lastname: Limongi
authors.forename: Maria
authors.initials: M
authors.lastname: Stepanova
authors.forename: Mariaelena
authors.initials: M
authors.lastname: Pierobon
authors.forename: Arian
authors.initials: A
authors.lastname: Afendy
authors.forename: Rohini
authors.initials: R
authors.lastname: Mehta
authors.forename: Ancha
authors.initials: A
authors.lastname: Baranova
authors.forename: Lance
authors.initials: L
authors.lastname: Liotta
authors.forename: Emanuel
authors.initials: E
authors.lastname: Petricoin
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use; D019540:Area Under Curve; D005260:Female; D019698:Hepatitis C, Chronic / Q000097:blood / Q000188:drug therapy / Q000378:metabolism* / Q000821:virology*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis / Q000378:metabolism*; D007370:Interferon Type I / Q000627:therapeutic use*; D007963:Leukocytes, Mononuclear; D008297:Male; D008875:Middle Aged; D010750:Phosphoproteins / Q000032:analysis / Q000378:metabolism; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D040081:Protein Array Analysis; D040901:Proteomics / Q000379:methods; D011994:Recombinant Proteins; D012044:Regression Analysis; D015203:Reproducibility of Results; D012254:Ribavirin / Q000627:therapeutic use*; D012680:Sensitivity and Specificity; D015398:Signal Transduction; D018709:Statistics, Nonparametric
chemical_list: D000998:Antiviral Agents; D036341:Intercellular Signaling Peptides and Proteins; D007370:Interferon Type I; D010750:Phosphoproteins; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin