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MicroRNA (miR) expression may help us predict long-term prognosis in diffuse large B-cell lymphoma (DLBCL), according to a study published in
Investigators identified 8 miRs that were differently expressed in DLBCL patients with poor prognosis and patients with favorable prognosis.
However, many of the miRs that have been linked to DLBCL prognosis in previous studies were not associated with prognosis in this study.
“Our data are in agreement with previous findings showing that miR signature is predictive of prognosis for patients with DLBCL, although with different miRs achieving statistical significance,” said study author Meir Lahav, MD, of Tel Aviv University in Israel.
Dr Lahav and his colleagues analyzed miR signatures from tissue biopsies taken from 83 patients with DLBCL who were treated between 1995 and 2003.
Patients who relapsed within 9 months from the start of treatment were defined as poor prognosis (n=43), and patients with disease-free survival of at least 5 years were defined as good prognosis (n=40).
The investigators analyzed RNA using microarrays developed by Rosetta Genomics. To validate the microarray results, the team used quantitative real-time polymerase chain reaction (qRT-PCR) and an independent set of 13 samples.
They found that 4 miRs were upregulated in the poor-prognosis group compared to the good-prognosis group: hsa-miR-17-5p, hsa-miR-19b-3p, hsa-miR-20a-5p, and hsa-miR-106a-5p.
And 4 miRs were downregulated in the poor-prognosis group compared to the good-prognosis group: hsa-miR-150-5p, hsa-miR-342-3p, hsa-miR-181a-5p, and hsa-miR-140-3p.
The investigators said the strongest and most consistent correlation was for miR-342-3p and miR-150-5p, which discriminated between the 2 prognostic groups in the microarray analysis, qRT-PCR, and the independent validation set.
Several miRs that were found to have prognostic value in previous studies did not differentiate the prognostic groups in this study. These were miR-155-5p, miR-21-5p, miR-18a-5p, miR-221-3p, and miR-222-3p. However, one miR—miR-181a-5p—had prognostic value in a previous study and the current study.
The investigators said the differences in miRs might be explained by the fact that this study had a larger sample size and longer follow-up than previous studies.
The differences might also reflect prognostic changes with rituximab treatment, as the patients in this study did not receive rituximab (only CHOP).
Either way, the investigators said these results suggest that analyzing miR expression can potentially improve our ability to predict prognosis in DLBCL and may therefore have a significant clinical impact.
