Background: δ-Tocotrienol is a naturally occurring proteasome inhibitor, which has the capacity to inhibit proliferation
and induce apoptosis in several cancer cells obtained from several organs of humans, and other cancer cell
lines. Moreover, results of plasma total mRNAs after δ-tocotrienol feeding to hepatitis C patients revealed significant
inhibition in the expression of pro-inflammatory cytokines (TNF-α, VCAM1, proteasome subunits) and induction in the
expression of ICAM1 and IFN-γ after post-treatment. This down-regulation of proteasome subunits leads to autophagy,
apoptosis of immune cells and several genes. The present study describes RNA-sequence analysis of plasma total
mRNAs obtained from δ-tocotrienol treatment of hepatitis C patients on gene expression regulated by proteasome.
Methods:Pooled specimens of plasma total mRNAs of pre-dose versus post-dose of δ-tocotrienol treatment of hepatitis
C patients were submitted to RNA-sequence analyses. The data based on > 1 and 8-fold expression changes of 2136
genes were uploaded into “Ingenuity Pathway Analyses (IPA)” for core analysis, which describes possible canonical
pathways, upstream regulators, diseases and functional metabolic networks.
Results:The IPA of “molecules” indicated fold change in gene expression of 953 molecules, which covered several
categories of biological biomarkers. Out of these, gene expression of 220 related to present study, 12 were up-regulated,
and 208 down-regulated after δ-tocotrienol treatment. The gene expression of transcription regulators (ceramide synthase
3 and Mohawk homeobox) were up-regulated, and gene expression of 208 molecules were down-regulated, involved in
several biological functions (HSP90AB1, PSMC3, CYB5R4, NDUFB1, CYP2R1, TNFRF1B, VEGFA, GPR65, PIAS1, SFPQ, GPS2,
EIF3F, GTPBP8, EIF4A1, HSPA14, TLR8, TUSSC2). IPA of “causal network” indicated gene regulators (676), in which 76 downregulated (26 s proteasomes, interleukin cytokines, and PPAR-ligand-PPA-Retinoic acid-RXRα, PPARγ-ligand-PPARγ-Retinoic
acid-RARα, IL-21, IL-23) with significant P-values. The IPA of “diseases and functions” regulators (85) were involved with
cAMP, STAT2, 26S proteasome, CSF1, IFNγ, LDL, TGFA, and microRNA-155-5p, miR-223, miR-21-5p. The IPA of “upstream
analysis” (934) showed 57 up-regulated (mainly 38 microRNAs) and 64 gene regulators were down-regulated (IL-2, IL-5, IL6, IL-12, IL-13, IL-15, IL-17, IL-18, IL-21, IL-24, IL-27, IL-32), interferon β-1a, interferon γ, TNF-α, STAT2, NOX1, prostaglandin
J2, NF-κB, 1κB, TCF3, and also miRNA-15, miRNA-124, miRNA-218-5P with significant activation of Z-Score (P < 0.05).
Conclusions:This is first report describing RNA-sequence analysis of δ-tocotrienol treated plasma total mRNAs
obtained from chronic hepatitis C patients, that acts via multiple-signaling pathways without any side-effects. These
studies may lead to development of novel classes of drugs for treatment of chronic hepatitis C patients.