1513A>C polymorphism in the P2X7 receptor gene in patients with papillary thyroid cancer: correlation with histological variants and clinical parameters.
BACKGROUND
The modulation of the purinergic receptor P2X7 may be implicated in human carcinogenesis. The 1513A>C and 489C>T polymorphisms of P2X7R gene induce loss of function and gain of function, respectively.


OBJECTIVE
The aim of the study was to assess the frequency of both 1513A>C and 489C>T polymorphisms in patients with papillary thyroid carcinoma (PTC) and to evaluate the possible association with clinical and histological features.


METHODS
P2X7R analysis was performed in lymphocytes from 121 PTC patients (100 women, 21 men; aged 43.4 +/- 13.6 yr), 100 matched healthy subjects, and 80 patients with nodular goiter.


RESULTS
The minor allele frequency for 1513A>C polymorphism in PTC patients with the classical variant was similar to controls (0.21 and 0.20, respectively), whereas it resulted in a significant increase in patients with the follicular variant (0.36; P = 0.01 vs. classical variant, and P = 0.005 vs. controls). In detail, 13.6% of patients with PTC follicular variant were homozygous for the 1513C allele, compared to 2.6% of patients with the classical variant and 2% of controls. Moreover, a positive relationship between 1513A>C polymorphism and either cancer diameter (Rho = 0.22; P = 0.02) or TNM stage (Rho = 0.38; P < 0.001) was found. No significant difference in the genotype frequency of 489C>T polymorphism between PTC patients and healthy controls was observed (0.42 and 0.47, respectively).


CONCLUSIONS
Our data show, for the first time, a strong association between 1513A>C polymorphism of P2X7R gene and the follicular variant of PTC. Further studies are needed to confirm the possible role of this polymorphism as a novel clinical marker of PTC follicular variant and its usefulness in selecting patients with different clinical outcome.
Dardano
Angela
A
Department of Internal Medicine, University of Pisa, via Roma 67, 56126 Pisa, Italy.
Falzoni
Simonetta
S
Caraccio
Nadia
N
Polini
Antonio
A
Tognini
Sara
S
Solini
Anna
A
Berti
Piero
P
Di Virgilio
Francesco
F
Monzani
Fabio
F
D000328:Adult; D014408:Biomarkers, Tumor / Q000235:genetics / Q000502:physiology; D002291:Carcinoma, Papillary / Q000235:genetics* / Q000473:pathology; D018265:Carcinoma, Papillary, Follicular / Q000235:genetics; D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006044:Goiter, Nodular / Q000235:genetics / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D018048:Receptors, Purinergic P2 / Q000235:genetics*; D058486:Receptors, Purinergic P2X7; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000473:pathology; D047368:Tumor Burden / Q000235:genetics
D014408:Biomarkers, Tumor; C546468:P2RX7 protein, human; D018048:Receptors, Purinergic P2; D058486:Receptors, Purinergic P2X7