Circulating microRNAs associated with prolonged overall survival in lung cancer patients treated with nivolumab

<p><b>Background:</b> The introduction of immune check-point inhibition in non-small cell lung cancer (NSCLC) therapy represents improved prospects for the patients. The response rates to check-point inhibitors are approximately 20% in unselected NSCLC patients. Increasing levels of tumor PD-L1 expression are associated with higher response rates. However, patients with low PD-L1 levels may also have durable responses, and improved strategies for patient stratification are needed.</p> <p><b>Material and methods:</b> In this study, we investigated circulating microRNAs aiming to identify circulating predictive biomarkers associated with increased overall survival after immune check-point treatment. Using next generation sequencing, we performed microRNA profiling in serum from NSCLC patients (<i>n</i> = 20) treated with nivolumab. Serum samples from 31 patients were used for validation using qPCR assays. Serum samples were collected prior to immune therapy initiation.</p> <p><b>Results:</b> Based on multivariate regression analysis, we identified a signature of seven microRNAs (miR-215-5p, miR-411-3p, miR-493-5p, miR-494-3p, miR-495-3p, miR-548j-5p and miR-93-3p) significantly associated with overall survival (OS) > 6 months in discovery cohort (<i>p</i> = .0003). We further validated this in another similar set of samples (<i>n</i> = 31) and the model was significantly associated with overall survival (OS) > 6 months (<i>p</i> = .001) with sensitivity and specificity of 71% and 90%, respectively.</p> <p><b>Conclusions:</b> In this study of circulating microRNAs, we have identified a 7-miR signature associated with survival in nivolumab-treated NSCLC patients. This signature may lead to better treatment options for patients with NSCLC, but a validation in an independent cohort is needed to confirm the predicted potential.</p

Biplot showing principal component analysis of <i>CK19</i>, <i>CEACAM5</i>, <i>DSG3</i>, <i>SFTPA</i> and <i>SFTPC</i> mRNA level in the 55 primary tumor biopsies.

<p>Black numbers indicate histology type (1 = adenocarcinoma, 2 = adenosquamous carcinoma, 3 = bronchioloalveolar carcinoma, 4 = carcinoid, 5 = large cell carcinoma, 6 = small cell carcinoma, 7 = squamous cell carcinoma).</p

Marker levels in non-small cell lung cancer (NSCLC) tumors (T), normal LNs (nN), patient LNs (ptN), normal blood (nB) and patient blood (ptB).

<p>Median values are indicated by short horizontal lines, whereas samples with levels below the limit of detection (LOD) are indicated below the dashed horizontal line. The levels of the different markers are relative to a calibrator sample and are not directly comparable.</p

Biplot showing the results from principal component analysis of the 16 tumor samples.

<p>The black circles show the sample data projected onto the first and second principal components. The red arrows shows the old variable axes projected unto the principal components.</p

Relative marker levels in non-small cell lung cancer (NSCLC) tumors (T), normal LNs (nN) and peripheral blood samples (nB).

<p>Median values are indicated by short horizontal lines, whereas samples with levels below the limit of detection (LOD) are indicated below the dashed horizontal line. The levels of the different markers are relative to a calibrator sample and not directly comparable.</p

Clinicopathological parameters according to molecular examination of regional LNs and peripheral blood samples.

*<p>Mann-Whitney test.</p

Number of patients with LNs and PB sampes positive for our 5 marker panel.

<p>Number of patients with LNs and PB sampes positive for our 5 marker panel.</p