Investigation of miR9-1, miR9-2 and miR9-3 Methylation in Hodgkin Lymphoma.
BACKGROUND
miR9 is an important tumor suppressor microRNA regulated by DNA methylation in various types of cancers.


METHODS
We analyzed the methylation status of the 3 members of the miR9 family in 58 cases of Hodgkin lymphoma (HL) in comparison to 15 reactive lymph nodes. We also assessed the relationships between miR9 methylation and Epstein-Barr virus (EBV) infection and several clinicopathological parameters.


RESULTS
We found that 84.5% of HL cases had a methylation in at least 1 of the 3 loci of miR9, whereas none of the nontumoral samples was methylated. The highest rate of methylation was found in miR9-2 (5q14.3) in 74.1% of the HL cases, followed by miR9-3 (15q26.1) in 56.9% and miR9-1 (1q22) in only 8.6% (p < 0.001). The promoter methylation of miR9-3 was more frequent in patients older than 15 years than in children (p = 0.02) and among women rather than men (p = 0.02). However, no significant correlation was found between miR9 methylation and EBV infection.


CONCLUSIONS
These results indicate that miR9 methylation, especially miR9-2, is a frequent event in HL and may be involved in HL pathogenesis, irrespective of EBV infection.
Department of Pathology, Farhat Hached University Hospital, Sousse, Tunisia.
Myriam
M
Ben Dhiab
Sonia
S
Ziadi
Teheni
T
Louhichi
Riadh
R
Ben Gacem
Feryel
F
Ksiaa
Mounir
M
Trimeche
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D019175:DNA Methylation; D020031:Epstein-Barr Virus Infections / Q000150:complications / Q000235:genetics / Q000821:virology; D005260:Female; D006689:Hodgkin Disease / Q000235:genetics* / Q000473:pathology / Q000821:virology; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D012737:Sex Factors; D055815:Young Adult
D035683:MicroRNAs