A case series and a systematic review of the literature on upregulated
miRs in gastric cancer: a story still to be told.
Abstract
Background: Recent literature documented the expression of miRs in
gastric cancer (GC), however their clinical utility is still unclear.
Methods and Results: 117 resected GCs were evaluated for miR21, miR135b,
miR196a, miR196b relative expression (RE). The performance of miRs’ to
differentiate cancer vs normal mucosa was tested using ROC curves.
Univariable and multivariable analyses were conducted to correlate miRs
RE with pathological features and survivals. Although all the 4 miRs
were upregulated, ROC curves documented that this was not-significant in
differentiating GC (p ns). miR135b significantly correlated with
Lauren’s intestinal type and more advanced pT stages (p 0.017, and p
0.025), whereas miR196a and miR196b were more expressed in advanced
pStages (p 0.016, and p 0.038). miR196b was also more expressed in nodal
positive patients comparing N0 (p 0.035). Survival curves were
non-significant for miRs RE, while pStages could significantly
differentiate oncological outcomes (p<0.0001). On Cox
analyses, pStages independently correlated with OS (HR 4.9, 95%CI
2.041-12.104), whereas increased age correlated with a worse DFS (HR
6.0, 95%CI 2.596-13.947), and lymph-node ratio with DSS (HR 14.4,
95%CI 4.213-49.373). Literature was reviewed a using PRISMA method
focusing on miRs and response to therapy and the detection of peritoneal
metastases: out of 116 manuscripts retrieved, just 41 were pertinent
with the outcomes of interest, and 14.6% were from Western countries.
miR21, miR135b and miR204 were reported to correlate with response to
therapy. Conclusions: miR21, miR135b, miR196a and miR196b were
documented up-regulated in GC, but their clinical utility is still to be
fully investigated.