Prognostic value of miRNAs in obstructive sleep apnea and metastatic colorectal cancer patients

<bold>Background:</bold> The relationship between obstructive sleep apnea (OSA) and cancer is recognized, but little is known about its mechanisms and impact on survival. Recent research has focused on the exploration of different biomarkers to understand the mechanisms underlying this relationship and miRNAs, that post-transcriptionally regulate gene expression, have emerged as possible actors of this process. <bold>Aims and objectives:</bold> We aimed to assess the impact of OSA on survival in metastatic colorectal cancer (mCRC) patients based on specific miRNA expression. <bold>Methods:</bold> The expression of miR-21, miR-23b, miR-26a, miR-27b, miR-145 and miR-210 was analyzed via qRT-PCR in patients’ sera. Response to first-line therapy, Kaplan-Meier curves of overall and progression-free survival were used to evaluate survival in mCRC patients with and without OSA stratified for the expression of miRNAs. <bold>Results:</bold> Our results revealed significantly elevated levels of miR-21, miR-23b, miR-26a and miR-210 in mCRC with OSA compared to no OSA. Conversely, levels of miR-27b and miR-145 were reduced in mCRC with OSA compared to cancer patients. Additionally, patients who experienced disease progression after first-line therapy had higher expression levels of miR-21, miR-23b, miR-26a and miR-210 than those with disease control. Kaplan-Meier analysis revealed reduced survival in mCRC with OSA when miR-21, miR-23b, miR-26a and miR-210 expression increased, while higher miR-27b and miR-145 levels were associated with improved survival outcomes. <bold>Conclusions:</bold> This study highlights the relevance of specific miRNAs on OSA in mCRC and their significance as non-invasive biomarkers in predicting the prognosis in patients with mCRC and OSA.