CD98hc as a marker of radiotherapy-resistant cancer stem cells in head and neck squamous cell carcinoma. Archives of medical science : AMS Introduction:The prognosis of head and neck squamous cell carcinoma (HNSCC) is generally good in cases of high radiation sensitivity but poor in cases exhibiting radiation resistance; this resistance has been attributed to the presence of cancer stem cells. In recent years, CD98hc overexpression has been associated with poor prognosis in various types of cancers. CD98 is a heterodimer of heavy and light chains and is strongly involved in cell proliferation, survival, migration, and adhesion. We investigated whether CD98hc can be used as a cancer stem cell marker for HNSCC. Material and methods:We exposed five HNSCC cell lines to a total radiation dose of 60 Gy administered in 2 Gy fractions on consecutive days to investigate changes in CD98hc expression. Furthermore, we separated CD98-positive and CD98-negative cell populations to comparatively investigate the properties of each. Results:Radiation resistance was observed in all five cell lines, and resistant cells exhibited CD98hc overexpression, with enhanced spheroid formation, migratory, and invasive abilities. Radiation-resistant cell lines were separated into CD98-positive and CD98-negative populations. CD98hc-positive radiation-resistant cell lines exhibited enhanced spheroid formation, invasion, and plating efficiency as well as strong tumorigenicity in nude mice. Conclusions:CD98hc-positive cells exhibited cancer stem cell-like properties in all cell lines. Thus, CD98hc is a potential marker of radiation sensitivity as well as a potential therapeutic target for improved survival rates of patients with HNSCC. 10.5114/aoms.2020.92872

Arginase-1 in Plasma-Derived Exosomes as Marker of Metastasis in Patients with Head and Neck Squamous Cell Carcinoma. Cancers Immunoregulatory Arginase-1 (Arg-1) is present in the tumor microenvironment of solid tumors. Its association to clinicopathology and its prognostic impact are inconsistent among different tumor types and biological fluids. This study evaluated Arg-1 protein levels in tumors and the circulation of patients with head and neck squamous cell carcinoma (HNSCC) in relation to clinical stage and prognosis. Tumor Arg-1 expression was monitored via immunohistochemistry while plasma Arg-1 levels via ELISA in 37 HNSCC patients. Arg-1 presence in plasma-derived exosomes was assessed using Western blots in 20 HNSCC patients. High tumor Arg-1 expression correlated with favorable clinicopathology and longer recurrence-free survival (RFS), while high plasma Arg-1 levels were associated with unfavorable clinicopathology. All patients with low tumor and high plasma Arg-1 had nodal metastases and developed recurrence. This discrepancy was attributed to the presence of Arg-1-carrying exosomes. Arg-1 was found in plasma-derived exosomes from all HNSCC patients. High exosomal Arg-1 levels were associated with positive lymph nodes and short RFS. Circulating Arg-1 exosomes represent a mechanism of active Arg-1 export from the tumor to the periphery. Exosomes reflected biologically relevant Arg-1 levels in metastatic HNSCC and emerged as potentially more accurate biomarkers of metastatic disease and RFS than tissue or plasma Arg-1 levels. 10.3390/cancers15225449

EVI1 as a Marker for Lymph Node Metastasis in HNSCC. Idel Christian,Ribbat-Idel Julika,Kuppler Patrick,Krupar Rosemarie,Offermann Anne,Vogel Wenzel,Rades Dirk,Kirfel Jutta,Wollenberg Barbara,Perner Sven International journal of molecular sciences BACKGROUND:HNSCC is the sixth most common cancer in humans and has still a very poor prognosis. The treatment methods so far are very often associated with mutilation and impairment in the quality of life. Except for p16 expression, there are no reliable prognostic markers in HNSCC so far. Ecotropic Viral Integration Site 1 (EVI1) is a well-described prognostic marker in leukemia and different types of solid cancers. In these, a high EVI1 expression is associated with a poor prognosis. In HNSCC, it is not known so far if EVI1 has any prognostic relevance. MATERIALS AND METHODS:We used our representative tissue cohort of 389 primary HNSCCs, of which 57.2% had one or more lymph node metastases. Here EVI1 expression was analyzed via immunohistochemistry and correlated with the clinical characteristics of these patients. RESULTS:Although in HNSCC EVI1 expression does not predict poor survival, a high EVI1 expression in the primary tumor correlates with a lymph node metastatic disease. CONCLUSION:Consequently, EVI1 may serve as a biomarker to predict an occult lymph node metastasis in a clinical nodal negative (cN0) HNSCC. 10.3390/ijms21030854