Programmed death-ligand 1 (PD-L1) is suggested to be a predictive biomarker in non-small-cell lung carcinoma (NSCLC). However, the differential expression of PD-L1 in primary lung tumor vs. synchronous metastases, especially brain metastasis (BM), remains unclear. This study assessed the concordance of PD-L1 expression on tumor cells and tumor infiltrating lymphocytes (TILs) and CD8⁺ TIL intensity between primary lung tumors and synchronous BMs from 24 NSCLC patients. PD-L1, CD3, and CD8 positivity was determined by immunohistochemistry (IHC). PD-L1 scoring was based on the proportion of tumor cells with membranous expression of PD-L1 and the cutoff values <1%, 1–49%, and ≥50%. CD3 and CD8 positivity in TILs was evaluated semi-quantitatively and the proportion of CD3⁺/CD8⁺ TILs was determined. PD-L1 expression on tumor cells and TILs was evaluated in relation to CD3⁺/CD8⁺ TIL proportions and the intensity of CD8⁺ TILs between the paired primary lung and BM tissues. In the primary lung tumors, PD-L1 positivity was observed in 25%, 37.5%, and 37.5% cases for the cutoff values <1%, 1–49%, and ≥50%, respectively. PD-L1 expression on tumor cells was strongly correlated between the paired primary lung and BM tissues, in all cutoff groups. However, PD-L1 expression on TILs and the proportion of CD3⁺/CD8⁺ TILs were not strongly correlated in all three groups between the paired primary lung tumors and BMs. The intensity of CD8⁺ TILs was concordant in only 54.16% of the paired primary lung tumors and BMs. This study showed a high concordance of PD-L1 expression in neoplastic cells between primary NSCLC and synchronous BMs.

Background: Driver mutations and immunological expressions have gained importance in recent years for targeted therapies and immunotherapies of nonsmall cell lung cancer (NSCLC). Aims: This study examined the association between PD-L1 expression and ALK, ROS1, and EGFR driver oncogene mutations in patients with NSCLC. Materials and Methods: A total of 501 NSCLC patients were included for analysis. Immunohistochemistry was performed with a PD-L1 clone 22c3. EGFR mutations were detected by PCR. ALK and ROS1 rearrangement analysis was performed with FISH. Results: There was a highly statistically significant difference between PD-L1 expression and EGFR mutation. PD-L1 expression was higher in the EGFR wild-type than in mutated EGFR (P = 0.0002). There was no relationship between PD-L1 expression and ALK and ROS1 mutations (P = 0.8899, P = 0.2512, respectively). PD-L1 expression was higher in nonadenocarcinomas (non-AC) than in adenocarcinomas (AC) (P = 0.0438). The ALK rearrangement and EGFR mutations were higher in ACs (P = 0.0073, P = 0.0012, respectively). ALK, ROS1 rearrangements, and EGFR mutations were higher in nonsmokers (P < 0.05). EGFR mutations were detected more frequently in females than males (P = 0.001). There was no relationship between gender and ALK, ROS1, and PD-L1 (P > 0.05). The prevalence of EGFR, ALK, and ROS1 driver mutations in the Turkish population was 9.3%, 5.3%, and 2.4%, respectively. Conclusions: In conclusion, PD-L1 expression and mutated EGFR status have a highly negative association. PD-L1 expression was higher in EGFR wild-type patients. Therefore, it shows that the opportunity to receive PD-L1-related treatment may be higher in these patients. We think that PD-L1 immunohistochemical evaluation will increase the clinical predictive importance in EGFR wild-type cases.

The study of ROS1 rearrangement in non-small cell lung carcinoma (NSCLC) has gained importance as it enables personalized treatment of NSCLC with tyrosine kinase inhibitors. Therefore, it is important that the ROS1 assessment tests become more standardized. In this study, we compared the two immunohistochemistry (IHC) antibodies (D4D6 and SP384 clones) and consistency with the fluorescence in situ hybridization (FISH) results in NSCLC. To investigate the effectiveness of the commonly used two IHC antibodies (SP384 and D4D6 clones) to detect ROS1 rearrangement in NSCLC. A retrospective cohort study. The study included 103 samples diagnosed with NSCLC, confirmed using IHC and FISH ROS1 results (14 positives, four discordant, and 85 consecutive negatives), with sufficient tissue samples (≥ 50 tumor cells). All samples were initially tested with ROS1-IHC antibodies (D4D6 and SP384 clones); their ROS1 status was then analyzed using the FISH method. Finally, samples with discordant IHC and FISH results were confirmed using the reverse transcription polymerase chain reaction method. The sensitivity of SP384 and D4D6 clones of ROS1 antibody was 100% with a ≥ 1 + cut-off. When the ≥ 2 + cut-off was used, the sensitivity rate for the SP384 clone was 100%, whereas the sensitivity for the D4D6 clone was 42.86%. ROS1 FISH rearranged samples were positive for both clones, but SP384 had generally higher intensity than D4D6. The mean IHC score was + 2 for SP384 and + 1.17 for D4D6. SP384 mostly tended to have a higher IHC score intensity, which made the evaluation easier than D4D6. SP384 has a higher sensitivity than D4D6. However, false positives were found in both clones. There was no significant correlation between ROS1 FISH-positivity percentage with SP384 (p = 0.713, p = 0.108) and D4D6 (p = 0.26, p = -0.323) IHC staining intensity. The staining patterns of both clones were similar (homogeneity/heterogeneity). Our findings show that the SP384 clone is more sensitive than D4D6. However, with D4D6, false-positive results have been observed in the SP384 clone. Knowing the variable diagnostic performance of different ROS1 antibodies before using them in clinical applications is necessary. IHC-positive results should be confirmed using FISH.

Objective: Laryngeal cancer is an aggressive malignancy in which immune regulatory mechanisms play a critical role in tumor progression and recurrence. The OX40/OX40L axis, a member of the tumor necrosis factor superfamily, has been implicated in immune modulation however, its genetic and soluble profiles in laryngeal cancer remain insufficiently characterized. Beyond cancer susceptibility, the clinical relevance of OX40/OX40L alterations in recurrence biology remains poorly understood.Materials and Methods: In this study, we investigated the distribution of OX40 rs17568 and OX40L rs1234313 polymorphisms and evaluated their association with serum soluble OX40 (sOX40) and OX40L (sOX40L) levels in 80 patients with laryngeal cancer and 111 healthy controls. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR--RFLP), and soluble protein levels were quantified by enzyme-linked immunosorbent assay (ELISA).Results: No significant differences in serum sOX40 or sOX40L levels were observed between patients and controls. While OX40 rs17568 genotype distributions were comparable between groups, a significant difference was detected for OX40L rs1234313, with homozygous genotypes (AA and GG) being more frequent in laryngeal cancer patients (p=0.007). Although genotype distributions were not associated with clinicopathological parameters, circulating sOX40 levels were significantly higher in patients with disease recurrence than in those without recurrence (p=0.008).Conclusion: The findings suggest that alterations in the OX40/OX40L axis may be associated with immune dysregulation during disease progression rather than cancer initiation in laryngeal cancer. Particularly, elevated circulating sOX40 levels were associated with disease recurrence. Given the cross-sectional and exploratory nature of the study, these findings should be interpreted with caution and require validation in larger prospective cohorts.

Objective: Laryngeal cancer is an aggressive malignancy in which immune regulatory mechanisms play a critical role in tumor progression and recurrence. The OX40/OX40L axis, a member of the tumor necrosis factor superfamily, has been implicated in immune modulation however, its genetic and soluble profiles in laryngeal cancer remain insufficiently characterized. Beyond cancer susceptibility, the clinical relevance of OX40/OX40L alterations in recurrence biology remains poorly understood.Materials and Methods: In this study, we investigated the distribution of OX40 rs17568 and OX40L rs1234313 polymorphisms and evaluated their association with serum soluble OX40 (sOX40) and OX40L (sOX40L) levels in 80 patients with laryngeal cancer and 111 healthy controls. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR--RFLP), and soluble protein levels were quantified by enzyme-linked immunosorbent assay (ELISA).Results: No significant differences in serum sOX40 or sOX40L levels were observed between patients and controls. While OX40 rs17568 genotype distributions were comparable between groups, a significant difference was detected for OX40L rs1234313, with homozygous genotypes (AA and GG) being more frequent in laryngeal cancer patients (p=0.007). Although genotype distributions were not associated with clinicopathological parameters, circulating sOX40 levels were significantly higher in patients with disease recurrence than in those without recurrence (p=0.008).Conclusion: The findings suggest that alterations in the OX40/OX40L axis may be associated with immune dysregulation during disease progression rather than cancer initiation in laryngeal cancer. Particularly, elevated circulating sOX40 levels were associated with disease recurrence. Given the cross-sectional and exploratory nature of the study, these findings should be interpreted with caution and require validation in larger prospective cohorts.

Introduction: Gastric cancers (GC) are one of the main causes of cancer-related deaths worldwide. Despite the dizzying progress in diagnostic and therapeutic strategies, many GC cases are diagnosed at advanced stages. Various signaling pathways have been identified to play vital roles in GC. Although the importance of these signaling pathways in GC has been demonstrated, further clinical studies are needed. Therefore, the expression of some signaling proteins in the tumoral and peri-tumoral microenvironments of GC are examined in this study. Methods: Protein expression levels were analyzed using Western blotting method in tumor and non-tumorous tissues from nine GC sufferers. The Kaplan-Meier method was used for the log-rank test to estimate survival curves and examine the survival distribution. Results: It was found that overexpression of c-MYC, mTOR, and AKT alongside decreased degrees of AMPK and TRAIL in GC tissues. Kaplan-Meier survival analysis highlighted worse survival outcomes in patients with high mTOR and AKT expression, while high TRAIL levels were associated with improved survival. Interestingly, a poorer prognosis was associated with higher c-MYC expression, highlighting the oncogenic role of this protein in GC through the AKT/mTOR pathway. On the other hand, decreased AMPK expression implied a lack of tumor-suppressive properties, most likely due to mTOR activation. Conclusion: These outcomes highlight the intricate interplay between GC's tumor-suppressive and carcinogenic mechanisms. Targeting these molecules by inhibiting mTOR or activating AMPK may provide new treatment approaches which can significantly increase TRAIL sensitivity. Moreover, further studies are necessary to confirm the present results and establish the integrated therapy approaches.