Detailed Characterization of the Lung-Gut Microbiome Axis Reveals the Link between PD-L1 and the Microbiome in Non-Small-Cell Lung Cancer Patients.

Next-generation sequencing technologies have started a new era of respiratory tract research in recent years. Alterations in the respiratory microbiome between healthy and malignant conditions have been revealed. However, the composition of the microbiome varies among studies, even in similar medical conditions. Also, there is a lack of complete knowledge about lung-gut microbiome interactions in lung cancer patients. The aim of this study was to explore the lung-gut axis in non-small-cell lung cancer (NSCLC) patients and the associations between lung-gut axis microbiota and clinical parameters (CRP, NLR, LPS, CD8, and PD-L1). Lung tissue and fecal samples were used for bacterial 16S rRNA sequencing. The results revealed, for the first time, that the bacterial richness in lung tumor tissue gradually decreased with an increase in the level of PD-L1 expression (p < 0.05). An analysis of ß-diversity indicated a significant positive correlation between the genera Romboutsia and Alistipes in both the lung tumor biopsies and stool samples from NSCLC patients (p < 0.05). Survival analysis showed that NSCLC patients with higher bacterial richness in their stool samples had prolonged overall survival (HR: 2.06, 95% CI: 1.025-4.17, p = 0.0426).

5'-Isoforms of miR-1246 Have Distinct Targets and Stronger Functional Impact Compared with Canonical miR-1246 in Colorectal Cancer Cells In Vitro.

Colorectal cancer (CRC) is a multifactorial disease involving genetic and epigenetic factors, such as miRNAs. Sequencing-based studies have revealed that miRNAs have many isoforms (isomiRs) with modifications at the 3'- and 5'-ends or in the middle, resulting in distinct targetomes and, consequently, functions. In the present study, we aimed to evaluate the putative targets and functional role of miR-1246 and its two 5'-isoforms (ISO-miR-1246_a and ISO-miR-1246_G) in vitro. Commercial Caco-2 cells of CRC origin were analyzed for the expression of WT-miR-1246 and its 5'-isoforms using small RNA sequencing data, and the overabundance of the two miR-1246 isoforms was determined in cells. The transcriptome analysis of Caco-2 cells transfected with WT-miR-1246, ISO-miR-1246_G, and ISO-miR-1246_a indicated the minor overlap of the targetomes between the studied miRNA isoforms. Consequently, an enrichment analysis showed the involvement of the potential targets of the miR-1246 isoforms in distinct signaling pathways. Cancer-related pathways were predominantly more enriched in dysregulated genes in ISO-miR-1246_G and ISO-miR-1246_a, whereas cell cycle pathways were more enriched in WT-miR-1246. The functional analysis of WT-miR-1246 and its two 5'-isoforms revealed that the inhibition of any of these molecules had a tumor-suppressive role (reduced cell viability and migration and promotion of early cell apoptosis) in CRC cells. However, the 5'-isoforms had a stronger effect on viability compared with WT-miR-1246. To conclude, this research shows that WT-miR-1246 and its two 5'-isoforms have different targetomes and are involved in distinct signaling pathways but collectively play an important role in CRC pathogenesis.

PD-L1 Expression and Tumour Microenvironment Patterns in Resected Non-Small-Cell Lung Cancer.

Background and Objectives: Although perioperative immunotherapy is implemented as a standard of care for resected non-small cell lung cancer (NSCLC), there is unmet need for predictive biomarkers as programmed death-ligand 1 (PD-L1) is not the perfect one. The functionality of tumour-infiltrating immune cells in the tumour microenvironment (TME) and the involvement in immune system response is one of the crucial factors that lead to pro- or anti-tumourigenic role and could predict response to PD-1 and PD-L1 inhibitors. So, the investigation of PD-L1 expression in the context of TME in early stages of resected NSCLC is urgent required. Materials and Methods: PD-L1 expression by three scoring methods: tumour proportion score (TPS), immune cell score (IC), and combined proportion score (CPS) was assessed in 72 archival tumour tissue specimens from stage I-III surgically resected NSCLC patients and associations with immune cells in TME were explored. Results: PD-L1 expression ≥1% evaluated by TPS, IC, and CPS was detected in 28%, 36%, and 39% of cases and moderate, substantial, and strong agreement between TPS and IC, TPS and CPS, CPS and IC was detected (Cohen's κ coefficient 0.556, 0.63, and 0.941, respectively). PD-L1 TPS, IC, and CPS correlated with smoking intensity defined as pack-years (r = 0.0305, p = 0.012; r = 0.305, p = 0.013, and r = 0.378, p = 0.002, respectively). Only PD-L1 TPS was associated with squamous cell carcinoma (p = 0.028). PD-L1 IC ≥1% was more often seen in tumours with high CD4+ T cells infiltration (p = 0.02), while PD-L1 CPS ≥1%-in tumours with high CD4+ and CD8+ T cells infiltration (p = 0.021 and p = 0.048, respectively). PD-L1 IC and CPS ≥10% was more often detected in tumours with greater number of tumour-infiltrating CD4+Foxp3+ T cells (p = 0.01 and p = 0.025, respectively). PD-L1 TPS ≥50% was associated with higher probability to detect greater number of tumour-infiltrating M2 macrophages (p = 0.021). No association was found between PD-L1 alone or in combination with tumour-infiltrating lymphocytes, macrophages, and disease-free or overall survival. Conclusions: This study results revealed that rates of PD-L1 expression correlated among three scoring methods (TPS, IC, and CPS). Moreover, PD-L1 expression was significantly associated with smoking intensity, squamous histology, and tumour-infiltrating immune cells.

Multiorgan Toxicity from Dual Checkpoint Inhibitor Therapy, Resulting in a Complete Response-A Case Report.

Immunotherapy treatment with checkpoint inhibitors (ICIs) has led to a breakthrough in the treatment of oncological diseases. Despite its clinical effectiveness, this treatment differs from others, such as cytotoxic chemotherapy, in that it causes immune-related adverse events. This type of toxicity can affect any organ or organ system of the body. We present a literature review and a rare clinical case from our clinical practice, in which a patient with metastatic clear cell renal carcinoma was treated with a single dose of dual checkpoint blockade (cytotoxic T-lymphocyte-4 (CTLA-4) and programmed death-1 (PD-1)) and simultaneously diagnosed with colitis, hepatitis, and nephritis. After early immunosuppressive treatment with the glucocorticoids, complete organ function recovery was achieved. The follow-up revealed a sustained complete response lasting more than a year.