Type 2-like polarization and elevated CXCL4 secretion of monocyte derived macrophages upon internalization of plasma-derived exosomes from head and neck cancer patients.

BACKGROUND: Exosomes are closely associated with different aspects of tumor-progression in patients with head and neck squamous cell carcinoma (HNSCC), such as angiogenesis or immune regulation. As extracellular vesicles they are involved in the intercellular communication by transferring their cargo such as proteins and nucleic acids from one cell to another. However, the influence of tumor related plasma-derived exosomes on the polarization and characteristics of monocyte derived macrophages is not fully understood. METHODS: Exosomes were isolated from plasma samples of healthy donors (HD) and HNSCC patients and further evaluated with regard to morphology, size and protein composition via transmission electron microscopy, nanoparticle tracking, western blot analysis and cytokine assays. Differentiation and characteristics of monocyte derived macrophages upon exosome internalization were analyzed using flow cytometry and fluorescence microscopy. Macrophage cytokine secretion patterns were analyzed by human cytokine antibody arrays and ELISA measurements. RESULTS: Our data revealed elevated overall plasma levels of CTLA-4, PD-L1, and TIM-3 as well as elevated exosome-associated CTLA-4, PD-L2, TIM-3, and LAG-3 levels in HNSCC patients compared to HD. Furthermore, we observed a significant type 2-like polarization and elevated CXCL4 secretion of monocyte derived macrophages upon internalization of plasma-derived exosomes from HNSCC patients, which could be visualized by fluorescence microcopy of membrane stained exosomes. CONCLUSIONS: The study provides new insights regarding exosome driven pro-tumorigenic immune regulation in the circulation of patients with head and neck cancer and could help to better understand the individual immunologic situation.

Partial recovery of peripheral blood monocyte subsets in head and neck squamous cell carcinoma patients upon radio(chemo)therapy is associated with decreased plasma CXCL11.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) represents a common and heterogeneous malignancy of the oral cavity, pharynx and larynx. Surgery and radio(chemo)therapy are the standard treatment options and also have great influence on the composition of the tumor microenvironment and immune cell functions. However, the impact of radio(chemo)therapy on the distribution and characteristics of circulating monocyte subsets in HNSCC are not fully understood. METHODS: Expression patterns of adhesion molecules and chemokine receptors CD11a (integrin-α L; LFA-1), CD11b (integrin-α M; Mac-1), CD11c (integrin-α X), CX3CR1 (CX3CL1 receptor) and checkpoint molecule PD-L1 (programmed cell death ligand-1) were investigated upon radio(chemo)therapeutic treatment using flow cytometry. Furthermore, comprehensive analysis of plasma cytokines was performed before and after treatment using ELISA measurements. RESULTS: Our data reveal a partial recovery of circulating monocytes in HNSCC patients upon radio(chemo)therapeutic treatment, with differential effects of the individual therapy regimen. PD-L1 expression on non-classical monocytes significantly correlates with the individual plasma levels of chemokine CXCL11 (C-X-C motif chemokine 11). CONCLUSIONS: Further comprehensive investigations on larger patient cohorts are required to elucidate the meaningfulness of peripheral blood monocyte subsets and chemokine CXCL11 as potential bioliquid indicators in HNSCC with regard to therapy response and the individual immunological situation.

Tumour ischaemia by interferon-γ resembles physiological blood vessel regression.

The relative contribution of the effector molecules produced by T cells to tumour rejection is unclear, but interferon-γ (IFNγ) is critical in most of the analysed models. Although IFNγ can impede tumour growth by acting directly on cancer cells, it must also act on the tumour stroma for effective rejection of large, established tumours. However, which stroma cells respond to IFNγ and by which mechanism IFNγ contributes to tumour rejection through stromal targeting have remained unknown. Here we use a model of IFNγ induction and an IFNγ-GFP fusion protein in large, vascularized tumours growing in mice that express the IFNγ receptor exclusively in defined cell types. Responsiveness to IFNγ by myeloid cells and other haematopoietic cells, including T cells or fibroblasts, was not sufficient for IFNγ-induced tumour regression, whereas responsiveness of endothelial cells to IFNγ was necessary and sufficient. Intravital microscopy revealed IFNγ-induced regression of the tumour vasculature, resulting in arrest of blood flow and subsequent collapse of tumours, similar to non-haemorrhagic necrosis in ischaemia and unlike haemorrhagic necrosis induced by tumour necrosis factor. The early events of IFNγ-induced tumour ischaemia resemble non-apoptotic blood vessel regression during development, wound healing or IFNγ-mediated, pregnancy-induced remodelling of uterine arteries. A better mechanistic understanding of how solid tumours are rejected may aid the design of more effective protocols for adoptive T-cell therapy.

TRIM21 Expression as a Prognostic Biomarker for Progression-Free Survival in HNSCC.

Patients with head and neck squamous cell carcinoma (HNSCC) continue to have a rather poor prognosis. Treatment-related comorbidities have negative impacts on their quality of life. TRIM21 is a cytosolic E3 ubiquitin ligase that was initially described as an autoantigen in autoimmune diseases and later associated with the intracellular antiviral response. Here, we investigated the role of TRIM21 as a biomarker candidate for HNSCC in predicting tumor progression and patient survival. We analyzed TRIM21 expression and its association with clinical-pathological parameters in our HNSCC cohort using immunohistochemistry. Our HNSCC cohort included samples from 419 patients consisting of primary tumors (n = 337), lymph node metastases (n = 156), recurrent tumors (n = 54) and distant metastases (n = 16). We found that cytoplasmic TRIM21 expression was associated with the infiltration of immune cells into primary tumors. In addition, TRIM21 expression was significantly higher in primary tumors than in lymph node metastases, and increased TRIM21 expression was correlated with shorter progression-free survival in HNSCC patients. These results suggest that TRIM21 could be a new biomarker for progression-free survival.

Tirofiban potentiates agonist-induced platelet activation and degranulation, despite effectively inhibiting aggregation.

We aimed to investigate the effects of integrin αIIbß3 inhibitor tirofiban on hallmarks of platelet activation, degranulation, and aggregation during its use to analyze activated but non-complexed platelets via flow cytometry. To do so, we used washed platelets from healthy human donors. We combined aggregometry, an assay of platelet functionality, with flow cytometry and ELISA to detect and correlate, respectively, platelet aggregation, activation, and granule release. While tirofiban effectively inhibited agonist-induced platelet aggregation (thrombin receptor-activating peptide 6 (TRAP), convulxin (CVX), U46619 and IV.3), the surface expression of P-selectin and CD63 and granule release of RANTES were significantly increased, indicating that tirofiban enhances degranulation, uncoupled from aggregation. The results show that tirofiban alters the activation phenotype of platelets, something that should be considered when using tirofiban to enable flow cytometric analysis of activated but unaggregated platelet suspensions.

Elevated LSD1 and SNAIL Expression Indicate Poor Prognosis in Hypopharynx Carcinoma.

Head and neck squamous cell carcinomas (HNSCC) are among the most common cancers worldwide and are associated with a poor prognosis for patients. Among HNSCC, those originating in the hypopharynx have the worst prognosis. The histone demethylase LSD1 has been shown to promote cancer initiation, progression, and relapse through various mechanisms and is upregulated in many cancer tissues. LSD1 physically interacts with SNAIL and is required for SNAIL mediated transcriptional repression. Previous studies of the prognostic value of LSD1 in HNSCC have been limited in their analysis of sub-sites, and a correlation between LSD1 and SNAIL has not been shown in HNSCC patient samples. Here we used a large, representative, and clinically well-characterized cohort of 339 HNSCC patients to investigate the co-expression of LSD1 and SNAIL and their prognostic value in all HNSCC using immunohistochemical staining. Elevated LSD1 expression correlated with advanced tumor stage and poor progression-free survival (PFS) in HNSCC originating in the hypopharynx. Overexpression of the transcription factor SNAIL independently correlated with worse overall survival (OS) and PFS in HNSCC in general and prominently in tumors of the hypopharynx. Furthermore, increased LSD1 expression significantly correlated with elevated SNAIL expression in patient samples. Therefore, the presented data implicates LSD1 and SNAIL as independent prognostic biomarkers.

Editorial for the Special Issue "Squamous Cell Cancer of the Head and Neck-Time to Arrive in the 21st Century of Oncology".

Squamous cell carcinoma of the head and neck (HNSCC) is the sixth most common cancer worldwide [...].

Cooperation of genes in HPV16 E6/E7-dependent cervicovaginal carcinogenesis trackable by endoscopy and independent of exogenous estrogens or carcinogens.

Human papillomavirus (HPV) infection is necessary but insufficient for progression of epithelial cells from dysplasia to carcinoma-in situ (CIS) to invasive cancer. The combination of mutant cellular and viral oncogenes that regulate progression of cervical cancer (CC) remains unclear. Using combinations of HPV16 E6/E7 (E+), mutant Kras (mKras) (K+) and/or loss of Pten (P-/-), we generated autochthonous models of CC without exogenous estrogen, carcinogen or promoters. Furthermore, intravaginal instillation of adenoCre virus enabled focal activation of the oncogenes/inactivation of the tumor suppressor gene. In P+/+ mice, E6/E7 alone (P+/+E+K-) failed to cause premalignant changes, while mKras alone (P+/+E-K+) caused persistent mucosal abnormalities in about one-third of mice, but no cancers. To develop cancer, P+/+ mice needed both E6/E7 and mKras expression. Longitudinal endoscopies of P+/+E+K+ mice predicted carcinoma development by detection of mucosal lesions, found on an average of 23 weeks prior to death, unlike longitudinal quantitative PCRs of vaginal lavage samples from the same mice. Endoscopy revealed that individual mice differed widely in the time required for mucosal lesions to appear after adenoCre and in the time required for these lesions to progress to cancer. These cancers developed in the transition zone that extends, unlike in women, from the murine cervix to the distal vagina. The P-/-E+K+ genotype led to precipitous cancer development within a few weeks and E6/E7-independent cancer development occurred in the P-/-E-K+ genotype. In the P-/-E+K- genotype, mice only developed CIS. Thus, distinct combinations of viral and cellular oncogenes are involved in distinct steps in cervical carcinogenesis.

EVI1 as a Marker for Lymph Node Metastasis in HNSCC.

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.

CDK19 as a Potential HPV-Independent Biomarker for Recurrent Disease in HNSCC.

The Mediator complex is a central integrator of transcription and a hub for the regulation of gene expression. Cyclin dependent kinase (CDK) 19 and its paralog CDK8 are part of its kinase domain and contribute to cancer progression in different cancer entities. STAT1 is an important immune modulator and a downstream substrate of CDK8/CDK19 mediated phosphorylation. So far, little is known about CDK19's role in head and neck squamous cell carcinoma (HNSCC) progression, its link to STAT1 activity, and related immune modulation. Immunohistochemistry for CDK19, activated pSTAT1, and PD-L1, known to be affected by STAT1, was conducted on samples of 130 primary tumors, 71 local recurrences, 32 lymph node metastases, and 25 distant metastases of HNSCC. Compared to primary tumors, CDK19 is overexpressed in local recurrences and distant metastases as well as in primary tumors that developed local recurrence after initial therapy. Patients with high-CDK19-expressing primary tumors have a significantly shorter disease-free survival. CDK19 expression correlates with pSTAT1 expression in primary tumors associated with recurrent disease, local recurrent tumors, lymph node metastases, and distant metastases. pSTAT1 expression correlates with PD-L1 expression in recurrent tumors. Our findings identify CDK19 as a potential biomarker in HNSCC to predict recurrent disease and support recent developments to target CDK19 and its paralog CDK8 in advanced cancer.

NR2F6 as a Prognostic Biomarker in HNSCC.

Head and neck squamous cell carcinoma (HNSCC)is the 6th most common cancer in humans worldwide and is associated with a poor prognosis for patients. NR2F6 has been identified as an immune checkpoint molecule in tumor-infiltrating T lymphocytes and is associated with a poor prognostic outcome in various cancers. The prognostic value of NR2F6 in HNSCC has not been described yet. We used a large, representative and clinically well-characterized cohort of 383 HNSCC patients, of which 22.4% developed a local recurrence. The NR2F6 expression was analyzed by using immunohistochemistry and was afterward correlated with clinical characteristics and clinicopathological features of HNSCC patients. Primary tumors from patients who develop a local recurrence have a higher NR2F6 expression than primary tumors which do not develop a local recurrence. Furthermore, a high NR2F6 expression is associated with poorer recurrence-free survival, although there is no correlation with overall survival. NR2F6 expression is independent of the T stage and UICC stage. NR2F6 might be a new prognostic biomarker for the early detection of local recurrences in HNSCC patients. Therefore, it may help to improve the recognition of patients who would benefit from more frequent follow-up examinations.

Immunometabolic Determinants of Chemoradiotherapy Response and Survival in Head and Neck Squamous Cell Carcinoma.

Tumor immune microenvironment and tumor metabolism are major determinants of chemoradiotherapy response. The interdependency and prognostic significance of specific immune and metabolic phenotypes in head and neck squamous cell carcinoma (HNSCC) were assessed and changes in reactive oxygen species were evaluated as a mechanism of treatment response in tumor spheroid/immunocyte co-cultures. Pretreatment tumor biopsies were immunohistochemically characterized in 73 HNSCC patients treated by definitive chemoradiotherapy and correlated with survival. The prognostic significance of CD8A, GLUT1, and COX5B gene expression was analyzed within The Cancer Genome Atlas database. HNSCC spheroids were co-cultured in vitro with peripheral blood mononuclear cells (PBMCs) in the presence of the glycolysis inhibitor 2-deoxyglucose and radiation treatment followed by PBMC chemotaxis determination via fluorescence microscopy. In the chemoradiotherapy-treated HNSCC cohort, mitochondrial-rich (COX5B) metabolism correlated with increased and glucose-dependent (GLUT1) metabolism with decreased intratumoral CD8/CD4 ratios. High CD8/CD4, together with mitochondrial-rich or glucose-independent metabolism, was associated with improved short-term survival. The Cancer Genome Atlas analysis confirmed that patients with a favorable immune and metabolic gene signature (high CD8A, high COX5B, low GLUT1) had improved short- and long-term survival. In vitro, 2-deoxyglucose and radiation synergistically up-regulated reactive oxygen species-dependent PBMC chemotaxis to HNSCC spheroids. These results suggest that glucose-independent tumor metabolism is associated with CD8-dominant antitumor immune infiltrate, and together, these contribute to improved chemoradiotherapy response in HNSCC.

Tumor-associated fibroblasts predominantly come from local and not circulating precursors.

Fibroblasts are common cell types in cancer stroma and lay down collagen required for survival and growth of cancer cells. Although some cancer therapy strategies target tumor fibroblasts, their origin remains controversial. Multiple publications suggest circulating mesenchymal precursors as a source of tumor-associated fibroblasts. However, we show by three independent approaches that tumor fibroblasts derive primarily from local, sessile precursors. First, transplantable tumors developing in a mouse expressing green fluorescent reporter protein (EGFP) under control of the type I collagen (Col-I) promoter (COL-EGFP) had green stroma, whereas we could not find COL-EGFP(+) cells in tumors developing in the parabiotic partner lacking the fluorescent reporter. Lack of incorporation of COL-EGFP(+) cells from the circulation into tumors was confirmed in parabiotic pairs of COL-EGFP mice and transgenic mice developing autochthonous intestinal adenomas. Second, transplantable tumors developing in chimeric mice reconstituted with bone marrow cells from COL-EGFP mice very rarely showed stromal fibroblasts expressing EGFP. Finally, cancer cells injected under full-thickness COL-EGFP skin grafts transplanted in nonreporter mice developed into tumors containing green stromal cells. Using multicolor in vivo confocal microscopy, we found that Col-I-expressing fibroblasts constituted approximately one-third of the stromal mass and formed a continuous sheet wrapping the tumor vessels. In summary, tumors form their fibroblastic stroma predominantly from precursors present in the local tumor microenvironment, whereas the contribution of bone marrow-derived circulating precursors is rare.

Radiotherapy related skin toxicity (RAREST-01): Mepitel® film versus standard care in patients with locally advanced head-and-neck cancer.

BACKGROUND: The aim of the present trial is to investigate a new option of skin protection in order to reduce the rate of grade ≥ 2 skin toxicity in patients receiving radiotherapy alone or radiochemotherapy for locally advanced squamous cell carcinoma of the head-and-neck (SCCHN). METHODS / DESIGN: This is a randomized, active-controlled, parallel-group multi-center trial that compares the following treatments of radiation dermatitis in patients with head-and-neck cancer: Mepitel® Film (Arm A) vs. standard care (Arm B). The primary aim of this trial is to investigate the rate of patients experiencing grade ≥ 2 radiation dermatitis (according to Common Toxicity Criteria for Adverse Events (CTCAE) Version 4.03) until 50 Gy of radiotherapy. Evaluation until 50 Gy of radiotherapy has been selected as the primary endpoint, since up to 50 Gy, the irradiated volume includes the primary tumor and the bilateral cervical and supraclavicular lymph nodes, and, therefore, is similar in all patients. After 50 Gy, irradiated volumes are very individual, depending on location and size of the primary tumor, involvement of lymph nodes, and the treatment approach (definitive vs. adjuvant). In addition, the following endpoints will be evaluated: Time to grade 2 radiation dermatitis until 50 Gy of radiotherapy, rate of patients experiencing grade ≥ 2 radiation dermatitis during radio(chemo)therapy, rate of patients experiencing grade ≥ 3 skin toxicity during radio(chemo)therapy, adverse events, quality of life, and dermatitis-related pain. Administration of Mepitel® Film will be considered to be clinically relevant, if the rate of grade ≥ 2 radiation dermatitis can be reduced from 85% to 65%. DISCUSSION: If administration of Mepitel® Film instead of standard care will be able to significantly reduce the rate of grade ≥ 2 radiation dermatitis, it could become the new standard of skin care in patients irradiated for SCCHN. TRIAL REGISTRATION: clinicaltrials.gov NCT03047174 . Registered on 26th of January, 2017. First patient included on 9th of May, 2017.

1,8-Cineol Attenuates Checkpoint Molecule PDL-1 and Adhesion Molecule CX3CR1 in Circulating Monocytes in Otitis Media Patients.

BACKGROUND: Peripheral blood monocytes can be subdivided into different subsets based on the CD14/CD16 surface characteristics. Monocytes are a major source of cytokine secretion of pro-inflammatory immune responses, whereas CD16+ monocyte subsets can also contribute to persistent inflammation in the context of chronic diseases. However, the regulation and cellular characteristics of circulating monocyte subsets in patients with chronic otitis media (COM), one of the largest public health burdens, remains largely unknown. MATERIALS AND METHODS: In this study, we analyzed individual distributions of circulating monocyte subsets and associated protein expression levels of adhesion protein and chemokine receptors CD11a (integrin-α L; LFA-1), CD11b (integrin-α M; Mac-1), and CD11c (integrin-α X), CX3CR1 (CX3CL1 receptor), as well as checkpoint molecule PD-L1 (programmed cell death ligand-1), in a gender-balanced cohort of 14 patients with chronic otitis media using flow cytometry, especially in view of the therapeutic impact of the natural plant-derived monoterpene oxide 1,8-Cineol. Furthermore, using the human monocyte cell line THP-1 as a model, we investigated the influence of anti-inflammatory 1,8-Cineol on monocytic cytokine secretion patterns using human cytokine arrays and ELISA measurements. RESULTS: The data revealed significantly elevated expression levels of all analyzed adhesion molecules in certain monocyte subsets in COM patients; CX3CR1 was especially significantly down-regulated in response to 1,8-Cineol administration. Moreover, the data revealed significantly increased monocytic PD-L1 expression levels in circulating classical and intermediate monocyte subsets from COM patients compared to healthy donors, but also a significant decrease in PD-L1 in intermediate monocytes upon 1,8-Cineol therapy compared to the pre-treatment situation. Furthermore, the increased secretion of cytokine CXCL10 by THP-1 monocytes in response to LPS was found to be strongly attenuated by 1,8-Cineol. Plasma levels of CXCL10 were also significantly increased in COM patients, but no significant differences between the pre and post 1,8-Cineol situation were observed. CONCLUSIONS: The present study revealed new insights into the bioactive anti-inflammatory effects of 1,8-Cineol in terms of monocyte adhesion and immune regulation. Our data suggest the potential role of cytokine CXCL10 in COM development and maintenance, which is also involved in the activity of its concomitant disease, rheumatoid arthritis.

Correction: Becker et al. Identifying Predictive Biomarkers for Head and Neck Squamous Cell Carcinoma Response. Cancers 2023, 15, 5597.

In the original publication [...].

Different Influence Pattern of Conventional and Alternative Sources of Smoking on Adhesion Molecules and Cytokine Secretion in THP-1 Monocytes.

BACKGROUND/AIM: Tobacco is a carcinogen that is closely associated with the occurrence of lung cancer and head and neck squamous cell carcinoma (HNSCC). The consumption of tobacco is also leading to alterations in different immune cell subtypes. However, the impact of different conventional and alternative smoking sources on human monocytes remains elusive. MATERIALS AND METHODS: In this study, we investigated the influence of aqueous extracts of different sources of smoking (cigarettes; heated tobacco product IQOS; e-cigarettes with and without nicotine; nicotine pouches) on different monocytic adhesion molecules, chemokine receptors and checkpoint molecule PD-L1 by flow cytometry. Cytokine expression patterns were evaluated using human cytokine arrays and the human monocyte leukemia cell line THP-1 as a model. RESULTS: Data revealed differential effects of the analyzed conventional and alternative smoking devices on monocyte adhesion molecules and cytokine secretion. The examined smoking devices can be assigned to two differential monocyte activation patterns. Monocytes stimulated with aqueous extracts of cigarettes, e-cigarette without nicotine, and heat not burn product IQOS revealed distinct alterations of surface markers and cytokines compared to the monocyte activation pattern in response to aqueous extracts of nicotine, nicotine pouches, and e-cigarette with nicotine. CONCLUSION: Our data indicate differential immunological consequences of different conventional and alternative smoking sources with and without nicotine. Further comprehensive analysis as well as in vivo investigations on peripheral blood monocyte subsets from smoking individuals using different smoking sources are required to better understand the impact on monocyte characteristics, especially with regard to the development of cancer.

Correlation of Intra-tumoral and Peripheral PD-1/PD-L1 Immunity in Head and Neck Cancer.

BACKGROUND/AIM: Head and neck squamous cell carcinoma (HNSCC) represents a heterogeneous malignant disease of the oral cavity, pharynx, and larynx. HNSCC cells evade the host immune system through alterations in their immunogenicity, production of immunosuppressive mediators, and induction of immunomodulatory cell types. The immune status of solid HNSCC can be considered as hot, cold, or excluded for each patient individually, based on the distribution of tumor infiltrating immune cells. In this context immunotherapies based on the blockade of checkpoint molecules programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) have significantly improved therapeutic outcomes in different cancer types. In HNSCC, intra-tumoral expression levels of PD-L1 are used for decision making in checkpoint inhibitor treatment. The significance of PD-L1 as a prognostic indicator is still controversial because both PD-1 and PD-L1 are also expressed in different types of circulating immune cells and the interaction of systemic and intra-tumoral cell-type-specific expression patterns of checkpoint molecules PD-1/PD-L1 has not yet been fully unveiled. MATERIALS AND METHODS: Using immunohistochemical (IHC) staining and flow cytometry, we correlated the expression patterns of the checkpoint molecules PD1/PD-L1 in peripheral blood CD14/CD16 monocytes and CD4/CD8 T cells with intra-tumoral conditions in patients with head and neck cancer. RESULTS/CONCLUSION: Our data demonstrate significant connections between systemic and intra-tumoral PD-1/PD-L1 immune patterns, both of which may serve as promising combined biomarkers for treatment decisions in patients with head and neck cancer.

Evaluation of the Impact of Smoking and Alcohol Consumption on Toxicity and Outcomes of Chemoradiation for Head and Neck Cancer.

BACKGROUND/AIM: Smoking and alcohol abuse may impair outcomes of chemoradiation for squamous cell head and neck cancer (SCCHN). Potential associations with toxicity, loco-regional control (LRC), and overall survival (OS) were investigated. PATIENTS AND METHODS: Ninety-six patients were retrospectively analyzed for impacts of pre-radiotherapy (pre-RT) smoking history, smoking during radiotherapy, and pre-RT alcohol abuse on toxicity, LRC, and OS. RESULTS: A trend was found for associations between pre-RT smoking history and grade ≥2 dermatitis. Smoking during radiotherapy was significantly associated with grade ≥3 mucositis and showed trends regarding grade ≥2 mucositis and dermatitis. On univariate analyses, smoking during radiotherapy was negatively associated with LRC and OS, pre-RT alcohol abuse with OS, and >40 pack years with LRC and OS. In multivariate analyses, smoking during radiotherapy remained significant for decreased OS, and pack years showed a trend. CONCLUSION: Smoking during radiotherapy was an independent predictor of OS and associated with increased toxicity. Thus, it is important to stop smoking prior to the start of radiotherapy.

Plasma­derived CD16 exosomes and peripheral blood monocytes as correlating biomarkers in head and neck cancer.

Exosomes play an important role in the individual immune regulation in patients with head and neck squamous cell carcinoma (HNSCC) as part of the tumor microenvironment. Patients with HNSCC with advanced tumor stages reveal significantly increased levels of plasma derived CD16+ (FcRIIIA) total exosomes as demonstrated in our previous study. Furthermore, increased individual abundances of peripheral blood CD16+ non-classical monocytes have been shown to correlate with increased monocytic programmed death ligand 1 (PD-L1) and CD4+ T cell disturbances in oropharyngeal cancer. However, the context of plasma derived CD16+ exosomes in patients with HNSCC and their role in the immune-regulation of circulating monocyte subsets has not been investigated so far. In the present study, exosomes were isolated from plasma samples of healthy donors and patients with HNSCC and evaluated for their morphology, size and protein composition using transmission electron microscopy, western blotting and bead-based flow cytometry. Monocyte subset abundances were analyzed in whole blood measurements in terms of the CD14/CD16 cell surface expression patterns, different monocytic adhesion molecules and checkpoint molecule PD-L1 using flow cytometry. Isolated exosomes were positive for the tetraspanins CD63 and CD9 as well as the endosomal marker TSG101, but negative for the non-exosomal marker glucose-regulated protein 94 and apolipoprotein ApoA1. Plasma derived CD16+ exosomes and exosome size distribution were significantly correlated with abundances of CD16+ non-classical monocytes and CD16+ intermediate monocytes, respectively. Furthermore, the data revealed significant correlations between CD16+ plasma derived exosomes and adhesion molecules CD29 (integrin ß1) and CX3CR1 on certain monocyte subsets. These data suggested that CD16 positive exosomes and exosome size distribution were potential surrogates to characterize the composition of monocyte subsets in patients with HNSCC. Overall, both CD16-positive exosomes and CD16-positive monocyte subsets are potential liquid biomarkers that could be used to characterize the individual immunological situation of patients with HNSCC.