MET and SLFN11 as a Players in the SCLC Molecular Subtyping Game

The possibilities of small-cell lung cancer (SCLC) therapy were strictly limited for years, leading to high patient mortality rates. New approaches to SCLC treatment are being proposed, including chemoimmunotherapy. However, biomarkers enabling appropriate personalization of therapy in SCLC patients have not been identified yet. Even though molecular subtyping (ASCL1, NEUROD1, POU2F3, and YAP1) seems pivotal in the management of SCLC, expression of other genes might be potentially valuable during patients’ stratification. Due to their crucial role in tumorigenesis and SCLC invasiveness, benefits arising from MET and SLFN11 gene evaluation are suggested. Our study was designed to evaluate the relationship between the mRNA expression of these genes and chemoimmunotherapy efficacy in SCLC patients. A total of 35 patients with extensive-stage SCLC (ES-SCLC) treated with first-line chemoimmunotherapy were involved in the study. mRNA expression of MET and SLFN11 genes was evaluated using the RT-qPCR technique in FFPE tissue collected from all patients. Molecular results were correlated with clinicopathological features and outcome of disease (OS, PFS). We detected SLFN11 expression in 60% (21 of 35) of the samples. SLFN11 expression was higher in patients with longer PFS (p = 0.05) and with the T4 feature in the TNM scale (p = 0.08). MET mRNA was expressed in all FFPE tissues. We observed that risk of progression and death was higher in patients with higher expression of MET mRNA (p = 0.06 and p = 0.04, respectively). Our study showed that MET and SLFN11 expression might serve as additional biomarkers for prediction of chemoimmunotherapy efficacy in ES-SCLC patients.