title: Apoptosis inhibition or inflammation: the role of NAIP protein expression in Hodgkin and non-Hodgkin lymphomas compared to non-neoplastic lymph node.
abstract: BACKGROUND
  Inhibitors of Apoptosis (IAP) family play a critical role in apoptosis and inflammatory response. Neuronal Apoptosis Inhibitory Protein (NAIP), as a member of both IAPs and NLR families (NOD-Like Receptor), is a unique IAP harboring NOD (Nucleotide Oligomerization Domain) and LLR (Leucine Rich Repeat) motifs. Considering these motifs in NAIP, it has been suggested that the main function of NAIP is distinct from other members of IAPs. As a member of NLR, NAIP mediates the assembly of 'Inflammasome' for inflammatory caspase activation. Pathologic expression of NAIP has been reported not only in some infectious and inflammatory diseases but also in some malignancies. However, there is no report to elucidate NAIP expression in lymphomatic malignancies.
  
  
  METHODS
  In this study, we examined NAIP protein expression in 101 Formalin-Fixed Paraffin-Embedded blocks including samples from 39 Hodgkin Lymphoma and 23 Non Hodgkin Lymphoma cases in comparison with 39 control samples (30 normal and 9 Reactive Lymphoid Hyperplasia (RLH) lymph nodes) using semi-quantitative immuno-flourecent Staining.
  
  
  RESULTS
  NAIP expression was not statistically different in lymphoma samples neither in HL nor in NHL cases comparing to normal samples. However, we evaluated NAIP expression in normal and RLH lymph nodes. Surprisingly, we have found a statistically significant-difference between the NAIP expression in RLH (M.R of NAIP/GAPDH expression = 0.6365 ± 0.017) and normal lymph node samples (M.R of NAIP/GAPDH expression = 0.5882 ± 0.047) (P < 0.01).
  
  
  CONCLUSIONS
  These findings show that the regulation of apoptosis could not be the main function of NAIP in the cell, so the pathologic expression of NAIP is not involved in lymphoma. But, we concluded that the over expression of NAIP has more effective role in the inflammatory response. Also, this study clarifies the NAIP expression level in lymphoma which is required for IAPs profiling in order to be used in potential translational applications of IAPs.
authors.affiliation: Dept of Genetics and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran. m_salehi@med.mui.ac.ir.
authors.forename: Safoura
authors.initials: S
authors.lastname: Mazrouei
authors.forename: Amin
authors.initials: A
authors.lastname: Ziaei
authors.forename: Amir Pouya
authors.initials: AP
authors.lastname: Tanhaee
authors.forename: Kianoosh
authors.initials: K
authors.lastname: Keyhanian
authors.forename: Mahdad
authors.initials: M
authors.lastname: Esmaeili
authors.forename: Azar
authors.initials: A
authors.lastname: Baradaran
authors.forename: Mansoor
authors.initials: M
authors.lastname: Salehi