Association of MICA-129 polymorphism with nasopharyngeal cancer risk in a Tunisian population

Association of Major Histocompatibility Complex Class 1 Chain-Related Gene A Dimorphism with Type 1 Diabetes and Latent Autoimmune Diabetes in Adults in the Algerian Population

“…In addition, MICA alleles may also be associated with susceptibility or resistance to developing autoimmunity (10). Recently, several authors have shown that the MICA-129 polymorphism was associated with several pathologies (9,14,23). In contrast, it has been demonstrated that a change of methionine to valine at position 129 of the ␣2-heavy chain domain classifies MICA alleles into strong (MICA-129 Met) or weak (MICA-129 Val) binders of NKG2D receptor (33).…”

“…MICA molecules were proven to play prominent roles in immune processes (33). The functional relevance of this variant in NK and T-cell activation led us to hypothesize that the type of NKG2D and MICA interaction with either high-affinity (MICA-129 Met) or low-affinity (MICA-129 Val) alleles favors chronic inflammation or tumor escape in subjects genetically predisposed to these immune disorders (2,14). The association of the HLA complex present on chromosome 6 does not alone explain the total linkage of the HLA region to T1D, leading to the hypothesis of the probable existence of additional causal genes for immune-related disorders in this region.…”

MICA (MHC class I polypeptide-related sequence A)

“…MICA alleles with a methionine (M) or valine (V) have been classified as having strong or weak binding affinity for NKG2D, respectively. These variable affinities have been suggested to affect thresholds of NK cell triggering and T cell modulation and consequently influencing clinical phenotypes in autoimmune disorders and malignancies (Amroun et al, 2005;Douik et al, 2009). MICA molecules exist also in soluble forms (sMICA) encompassing three extracellular domains (Salih et al, 2002).…”

“…Note MICA 129 M/V dimorphism with variable NKG2D binding affinities has been reported to affect thresholds of NK cell triggering and T cell modulation in malignancies (Douik et al, 2009). In cancer patients, elevated sMICA levels are significantly correlated with cancer stage, differentiation, and metastasis (Holdenrieder et al, 2006).…”

Nasopharyngeal Cancer – An Expanding Puzzle – Claiming for Answers

“…MICA is highly polymorphic, with more than 60 alleles (defined by nucleotide substitutions within exons encoding the three alfa-domains) described to date. Each of these variants is characterized by the presence of a variable number of short tandem repeats (STRs) within the exon encoding for the transmembrane region of the molecule (Douik, Ben Chaaben et al 2009). There are multiple evidences that the MICA*A9 is linked with several of those HLA haplotypes NPC related (HLA-B35, -B38, -B39, -B51, -B58) (Chan, Day et al 1983;Wu, Hwang et al 1989;Zhu, Chen et al 1990;Tian, Boggs et al 2001).…”