Abnormal expression of C3ORF9 gene in patients with myelodysplastic syndromes.

Myelodysplastic Syndrome (MDS) cells present genetic instability and dysregulation of the gene C3ORF9, which was isolated from an MDS cDNA library and codes for a putative protein. We studied the expression of C3ORF9 in MDS syndromes to contribute to the understanding of the pathophysiology of MDS. One hundred and thirty-one patients and 35 healthy controls were involved in our study. Bone marrow aspirates and isolated CD34+ cells were used. Gene expression was estimated by quantitative PCR. C3ORF9 was found to be down-regulated in patients with CMML compared to the controls (p<0.01). There was no difference between RARS and the controls (p=0.1), while increased expression was found in RA, RAEB and RAEB-T (p<0.01 for all). No mutations or polymorphism were detected in our population. CD34+ cells expressed higher levels of C3ORF9 (p<0.01) in patients. The gene expression was correlated to the percentage of +cells in RAEB and RAEB-T (r=0.64). The altered C3ORF9 expression was possibly due to different gene regulation in these patients and/or to the increased CD34+ cells.