Quantitative proteomics identifies biomarkers to distinguish pulmonary from head and neck squamous cell carcinomas by immunohistochemistry.

The differentiation between a pulmonary metastasis and a newly developed squamous cell carcinoma of the lung in patients with prior head and neck squamous cell carcinoma (HNSCC) is difficult due to a lack of biomarkers but is crucially important for the prognosis and therapy of the affected patient. By using high-resolution mass spectrometry in combination with stable isotope labelling by amino acids in cell culture, we identified 379 proteins that are differentially expressed in squamous cell carcinomas of the lung and the head and neck. Of those, CAV1, CAV2, LGALS1, LGALS7, CK19, and UGDH were tested by immunohistochemistry on 194 tissue samples (98 lung and 96 HNSCCs). The combination of CAV1 and LGALS7 was able to distinguish the origin of the squamous cell carcinoma with high accuracy (area under the curve 0.876). This biomarker panel was tested on a cohort of 12 clinically classified lung tumours of unknown origin after HNSCC. Nine of those tumours were immunohistochemically classifiable.

Human microRNA-182-5p and kinectin 1: Potential biomarkers for prognosis in oral squamous cell carcinoma.

BACKGROUND: The prognostic impact of hsa-miRNA-182-5p in oral cancer remains unexplored. Therefore, the aim of this study was to investigate the prognostic value of hsa-miRNA-182-5p and its predicted target kinectin 1 (KTN1) in oral squamous cell carcinoma (OSCC). METHOD: Expression level of hsa-miRNA-182-5p was analyzed in tumor tissue (n = 36) and healthy oral mucosal tissue (n = 17) using quantitative real-time polymerase chain reaction. Protein level of the predicted target KTN1 was detected via immunohistochemistry. Results were validated in a cohort of The Cancer Genome Atlas (TCGA). RESULTS: After dividing the data into a subgroup with high and low hsa-miRNA-182-5p expression level, a significant better overall (p = 0.016), recurrence-free (p = 0.009), and progression-free survival (p = 0.004) was observed in an upregulation of hsa-miRNA-182-5p. Staining intensity of KTN1 showed a reciprocal impact on the prognosis. Validation in a TCGA cohort confirmed these results. CONCLUSION: Our results indicate hsa-miRNA-182-5p and KTN1 as potential biomarkers for OSCC.