Differential Expressed Genes and Pathways Associated with Disease
Severity In Siblings with Cystic Fibrosis
Cystic fibrosis is an autosomal recessive disease caused by CFTR gene
mutations. Despite having the same mutation, CF patients may demonstrate
clinical variability in severity and prognosis of the disease. In this
study, we aimed to determine differentially expressed genes and
associated molecular pathways between mild and severe siblings with same
genotype. We performed targeted real-time PCR based transcriptomic
analysis of nasal epithelial cells obtained from two families with two
siblings with Class II mutations (F508del/F508del) and (F508del/G85E),
one family with three siblings with Class IV mutation (I1234V/I1234V).
In severe siblings with Class II mutations, TNFRSF11A, KCNE1, STX1A,
SLC9A3R2 were found to be up regulated. CXCL1, CFTR, CXCL2 were found to
be down regulated. Inflammation-immune response related signaling
pathways such as IL-17, NF-kappa B, TNF, NOD-like receptor signaling
were identified. In the severe sibling with Class IV mutation;
inflammation and immune response-related pathways were discovered. Also,
AGE-RAGE and TLR signaling were found to be specific to Class IV group.
Comparison of CF patients to non-CF control; showed that ICAM1 was up
regulated whereas EZR, TNFRSF1A, HSPA1A were down regulated in patients.
In addition, a significant positive correlation was determined between
differentially expressed genes in AGE-RAGE, cytokine-cytokine receptor
interaction, insulin resistance and hepatic involvement in CF patients.
As a result of this study, differentially expressed genes and associated
pathways responsible for clinical severity among affected siblings
carrying the same mutation were identified. The results will provide an
opportunity for the development of novel target molecules for treatment