Changes in circulating exosome molecular profiles following surgery/(chemo)radiotherapy: early detection of response in head and neck cancer patients

BACKGROUND

Head and neck cancers (HNSCC) are highly immunosuppressive. Plasma-derived exosomes of HNSCC patients carry immunomodulatory molecules, and their cargo correlates with clinical parameters. Here, we evaluated the exosomal molecular profile for early detection of treatment failure in locally advanced HNSCC patients treated with conventional therapy.

METHODS

Plasma from 17 HNSCC patients was collected before, during, and after treatment by surgery with adjuvant (chemo)radiation and at recurrence. Exosomes were isolated by size-exclusion chromatography. Total exosomal protein (TEP) was used to estimate exosome load and on-bead flow cytometry to evaluate relative fluorescence intensity (RFI) of tumour-associated and immunoregulatory proteins on exosomes. Exosomal effects on the activity of and adenosine production by T cells was assessed by flow cytometry and mass spectrometry.

RESULTS

TEP and the ratio of tumour-/immune-cell-derived exosomes varied during and after therapy with an overall decrease in the tumour-free follow-up but an increase at recurrence. RFI values of immunoregulatory proteins on exosomes, their ability for T cell inhibition and adenosine production changed during and after therapy. PD-L1 was the earliest discriminator for treatment failure and disease-free survival.

CONCLUSIONS

Monitoring of plasma exosomes during therapy represents a promising opportunity for early detection of treatment failure and risk stratification to delay/avoid recurrence.

Influence of travel burden on tumor classification and survival of head and neck cancer patients

PURPOSE

Cancer patients have to overcome various barriers to obtain diagnostics and treatment at head and neck cancer centers. Travel distance to a specialized hospital may result in psychosocial and financial distress, thus interfering with diagnostics, treatment, and follow-up care. In this study, we have aimed to analyze the association of travel distance with cTNM status, UICC stage at primary diagnosis, and survival outcomes of head and neck cancer (HNC) patients.

METHODS

We have analyzed data of 1921 consecutive HNC patients diagnosed between 2014 and 2019 at the head and neck cancer center of the Comprehensive Cancer Center Ulm (CCCU), Germany. Postal code-based travel distance calculation in kilometers, TNM status, and UICC stage were recorded at initial diagnosis. The assembly of travel distance-related groups (short, intermediate, long-distance) has been investigated. Moreover, group-related survival and recurrence analysis have been performed.

RESULTS

In contrast to observations from overseas, no association of travel distance and higher cTNM status or UICC stage at primary diagnosis has been observed. Furthermore, no significant differences for recurrence-free survival and overall survival by travel distance were detected.

CONCLUSION

In southern Germany, travel distance to head and neck cancer centers seems to be tolerable. Travel burden is not synonymous with travel distance alone but also involves sociodemographic, monetary, and disease-specific aspects as well as accessibility to proper infrastructure of transport and health care system.

Adenosine production in mesenchymal stromal cells in relation to their developmental status

BACKGROUND

Mesenchymal stromal cells (MSC) are multipotent progenitor cells found in the tumor microenvironment. They have an innate and regulatory immune activity, and they are able to produce immunosuppressive adenosine (ADO) via their ectonucleotidases CD39 and CD73. The present study explores ADO metabolism of MSC in relation to their developmental status.

METHODS

We analyzed MSC (n = 6), chondrogenic progenitor cells (CPC, n = 8), and chondrocytes (n = 8) for surface markers by flow cytometry. The ability to hydrolyze ATP and to produce ADO was tested by luminescence assays and mass spectrometry.

RESULTS

Significant differences in the surface marker expression of MSC, CPC, and chondrocytes were seen. While the expression of CD73 was observed to be the same on all cell types, the expression of the ectonucleotidase CD39 was significantly increased on MSC. Consequently, production of ADO was most abundant in MSC as compared with chondrocytes and CPC.

CONCLUSION

Mesenchymal stromal cells are potent producers of ADO and are, therefore, able to increase immunosuppression. As MSC differentiate into chondrocytes, they lose this ability and may take on other functions.

Age-related changes in T lymphocytes of patients with head and neck squamous cell carcinoma

Introduction

The number of aging cancer patients has increased continuously and will do so further in the future. The immune system of elderly people experiences critical changes over the time. Therefore, tumor-induced changes in the immune system are believed to differ in young and elderly cancer patients as well.

Methods

The effect of aging on the immune system was measured in peripheral blood lymphocytes (PBL) of healthy volunteers (n = 48, 21–84 yrs.) divided into three different age groups. Seventy years was set as a cut-off for defining subjects as elderly. Results were compared to two groups of adult cancer patients, which donated PBL and tumor infiltrating lymphocytes (TIL): young cancer patients (40–69 yrs.; blood: n = 13; TIL: n = 17) and elderly cancer patients (70–90 yrs.; blood: n = 20; TIL: n = 15) with head and neck squamous cell carcinoma (HNSCC). Frequencies and phenotypes of CD4⁺ and CD8⁺ T cells as well as regulatory T cells (T_reg) were assessed by flow cytometry.

Results

We observed lower frequencies of CD8⁺ cytotoxic T cells during aging in both groups. Frequencies of tumor infiltrating regulatory T cells were significantly higher than in the peripheral blood but showed a significant decline in older tumor patients. With increasing age, expression of immunosuppressive CD73 and CCR7 was lower and expression of PD1 elevated on peripheral T cells in healthy volunteers and tumor patients.

Conclusion

Immunosenescence takes place in healthy donors and cancer patients. Our results suggest that in elderly tumor patients, the immune system is impaired and the tumor-induced immune escape is less pronounced. The increased expression of PD1 implies the potential for effective immunotherapies in elderly, as treatment with checkpoint inhibitors could be more beneficial for elderly HNSCC patients.

[Immunotherapy highlights of the ASCO annual meeting 2018 for head and neck cancers]

BACKGROUND

Immunotherapeutic strategies are becoming increasingly more important for head and neck cancer and numerous clinical trials were presented at the annual meeting of the American Society of Clinical Oncology (ASCO) 2018.

OBJECTIVE

In this review the most interesting clinical trials and trial results for immunotherapy of head and neck cancer are summarized.

MATERIAL AND METHODS

All abstracts and presentations on immunotherapy of head and neck cancer at the annual meeting of the ASCO 2018 were screened to select the most interesting trials for a more detailed analysis.

RESULTS

For head and neck cancer, practice changing phase III trial results were missing, but several noteworthy new strategies and trial results for immunotherapy were presented. Neoadjuvant immunotherapy trials, results concerning immunotherapy in old age, prognostic implications of immune-mediated adverse events and new immunotherapy combinations are summarized in this article.

CONCLUSION

The role of immunotherapy for the treatment of head and neck cancer is markedly increasing. Many pioneering trials are currently ongoing, in the phase of data analysis or in planning.

Palliative treatment standards for head and neck squamous cell carcinoma : Survey of clinical routine in German-speaking countries

BACKGROUND

The EXTREME (Erbitux in First-Line Treatment of Recurrent and Metastatic Head and Neck Squamous Cell Carcinoma) protocol is generally considered the gold standard in palliative first-line treatment. However, there is some disagreement about its effectivity, toxicity, and applicability in daily clinical routine. The purpose of this cross-sectional survey was to describe the palliative treatment offered in German-speaking countries.

METHODS

From November 2013 to July 2014, 204 departments of otorhinolaryngology (ORL) in Germany, Austria, and the German-speaking parts of Switzerland were contacted and invited to take part in a web-based survey on the treatment of HNSCC.

RESULTS

In all, 62 of 204 treatment centers (30.4 %) participated in the survey. Of these, 58 departments offered palliative systemic therapy to their patients; 19 of 58 (32.8 %) treated patients undergoing palliative chemotherapy in their own ORL departments, while 40 of 58 (69 %) upheld a cooperation with medical oncologists in the same hospital and 24 of 58 (41.4 %) with medical oncologic practices. Many of these treatment centers offered multiple locations for treatment. Of the 58 departments, 56 provided an institutional standard for first-line palliative treatment, 13 for second-line, and two for third-line treatment. In 42 of 58 departments the EXTREME protocol was the institutional standard of care for first-line treatment. Moreover, 12 of 58 departments mentioned an individual protocol and two of 58 the inclusion in clinical trials as their local standard. The assessment of patients who could be treated with the first-line standard ranged from 0 to 95 % with a mean of 44.5 %.

CONCLUSION

Palliative systemic therapy seems to be well standardized for first-line treatment, whereas there is little standardization in second- and third-line treatments. A large variation was found regarding the estimate of the applicability of the institutional standard. Reasons for this could be the physicians' individual experience as well as the varying assessment regarding the toxicity of palliative systemic therapy.

[Immunotherapeutic studies of head and neck tumors : Highlights of the 2016 ASCO Annual Meeting]

Immunotherapeutic drugs in the form of novel immune checkpoint inhibitors have had a significant impact on and revival of the treatment standards for head and neck tumors. Recently, at the annual meeting of the American Society of Clinical Oncology (ASCO) several innovative immunotherapies in head and neck cancer were presented, which might lead to a paradigm shift in the palliative as well as curative setting in the near future.The most common approaches are antibodies targeting the programmed cell death 1 (PD-1) axis. These therapies seem to be effective in a significant proportion of patients (independent of human papillomavirus) and show an extended duration of response.In a phase III trial for palliative second-line therapy, the PD-1 antibody nivolumab demonstrated a significant improvement in survival in patients with head and neck squamous cell carcinoma (HNSCC) who were experiencing disease progression after platinum-based therapy; therefore, the Food and Drug Administration gave it a breakthrough therapy designation.Further clinical trials focusing on first-line palliative treatment (compared with the EXTREME protocol) as well as neoadjuvant therapies using immune checkpoint-inhibitors are ongoing. However, valid testing systems (e. g., PD-L1 testing) as well as reliable predictive markers for patient selection are necessary to avoid increasing public health costs and to protect patients from potentially serious adverse events.

Response Evaluation in Head and Neck Oncology: Definition and Prediction

Curative treatment of head and neck squamous cell carcinoma includes surgery and/or (chemo)radiation, whereas in the palliative setting, chemotherapy and/or immunotherapy represent(s) the standard approach. With regard to quality control, methods for determining treatment response are sorely needed. For surgical therapy, histopathology is the standard quality control. Established criteria for high-risk patients include resection margins of the primary tumor and extracapsular extension of lymph node metastases. After definitive chemoradiation, treatment response is generally evaluated by tomographic imaging combined with endoscopy including re-biopsy of the tumor region. Single-cycle induction chemotherapy may be used to determine the radiosensitivity of tumors, helping to define surgical and nonsurgical treatment options. Innovative approaches with implications for prognosis include the analysis of immune infiltrates, liquid biopsy, molecular characterization (proteomics, genomics), molecular and functional imaging (PET-CT, PET-MRI), as well as advanced imaging data analysis (radio[geno]mics/texture analysis). Human papilloma virus, as a prognostically relevant parameter, is currently being investigated for de-escalation strategies. With regard to the extended personalization of oncologic therapy, markers predicting treatment response are desirable and seem to be important, also from a socioeconomic perspective.

[Immunotherapy for HNSCC : Quo vadis?]

BACKGROUND

Immunotherapy remains a hot topic with an endless stream of new upcoming clinical trials. The results of studies to date are promising for second-line palliative treatment of head and neck squamous cell carcinoma (HNSCC). The next step is testing these strategies in randomized trials for first-line and curative treatment in an adjuvant, neoadjuvant, and primarily nonsurgical setting. So far, established biomarkers have not proven reliable enough to predict response rates precisely.

OBJECTIVES

On occasion of the annual meeting of the American Society of Clinical Oncology (ASCO), we aimed to invesitage the future of immunotherapies.

METHODS

We collected the most promising upcoming studies alongside current research in the field of biomarkers with a  view to interesting new immunotherapeutic strategies.

RESULTS

The search for appropriate biomarkers in particular seems to be a central research objective in the short term. There is a broad range of new agents that will be tested in clinical trials as well as the combination of immunotherapy with chemo- and chemoradiotherapy or other immune-modulating drugs.

CONCLUSION

The real challenge will be to find the most fitting therapy for each patient out of a large panel of available regimens. Therefore, it is most important to find a set of reliable biomarkers that together could predict treatment response.

Life or death by NFκB, Losartan promotes survival in dy2J/dy2J mouse of MDC1A

Inflammation and fibrosis are well-defined mechanisms involved in the pathogenesis of the incurable Laminin α2-deficient congenital muscular dystrophy (MDC1A), while apoptosis mechanism is barely discussed. Our previous study showed treatment with Losartan, an angiotensin II type I receptor antagonist, improved muscle strength and reduced fibrosis through transforming growth factor beta (TGF-β) and mitogen-activated protein kinases (MAPK) signaling inhibition in the dy^2J/dy^2J mouse model of MDC1A. Here we show for the first time that Losartan treatment up-regulates and shifts the nuclear factor kappa B (NFκB) signaling pathway to favor survival versus apoptosis/damage in this animal model. Losartan treatment was associated with significantly increased serum tumor necrosis factor alpha (TNF-α) level, p65 nuclei accumulation, and decreased muscle IκB-β protein level, indicating NFκB activation. Moreover, NFκB anti-apoptotic target genes TNF receptor-associated factor 1 (TRAF1), TNF receptor-associated factor 2 (TRAF2), cellular inhibitor of apoptosis (cIAP2), and Ferritin heavy chain (FTH1) were increased following Losartan treatment. Losartan induced protein expression toward a pro-survival profile as BCL-2 expression levels were increased and Caspase-3 expression levels were decreased. Muscle apoptosis reduction was further confirmed using terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) assay. Thus, along with TGF-β and MAPK signaling, NFκB serves as an important regulatory pathway which following Losartan treatment promotes survival in the dy^2J/dy^2J mouse model of MDC1A.

[Molecular approaches to systemic therapy of adenoid cystic carcinoma of the head and neck area]

The adenoid cystic carcinoma (ACC) is a neurotropic salivary gland tumor with a high blood-borne metastasis tendency. The treatment of choice for localized disease consists of radical surgical resection and, depending on resection status, adjuvant radiotherapy. Due to the high recurrence rate with limited local therapeutic options and frequent occurrence of distant metastases, one is confronted inevitably with the search for an adequate systemic therapy. ACC shows little response to a variety of chemotherapeutic agents, partial or complete remissions are extremely rare. Beside classical chemotherapies, immunotherapeutics and targeted therapies with more favorable side effect profiles were tested in trials, but due to the small number of patients, a definitive statement on the effectiveness can be hardly made. This results in the need for prospective multicenter studies that allow clear recommendations for systemic therapy of the tumor. The present paper gives an overview of the sub-cellular and genetic characteristics of ACC, which represent possible targets for systemic therapies and have partly already been included in running clinical trials.

[New aspects in the therapy of recurrence and metastasis of head and neck cancer: highlights from the 2012 ASCO meeting]

The majority of patients with a squamous cell carcinoma of the head and neck region (HNSCC) initially present in a locally advanced stage of the disease. Despite aggressive protocols in first-line treatment, some of these patients develop locoregional recurrences or metastases and are, in particular, extraordinarily challenging for the multidisciplinary treatment team. Therefore, among resectability and prior therapy, age, performance status and individual expectations of the patient have to be taken into account. Apart from surgical options like salvage surgery, chemotherapy and target therapy as well as reirradiation are possible treatment concepts. Unfortunately, most treatment options offer only little to no survival benefit.

[The most important results on primary chemoradiation for head and neck squamous cell carcinoma: highlights from the 2012 ASCO meeting]

Primary concomitant and sequential chemoradiation is a commonly used therapeutic strategy for head and neck squamous cell carcinoma. At the annual meeting of the 2012 American Society of Clinical Oncology numerous trial results were presented. A selection of the most important trials will be summarized in this article. This year, several important results from phase III trials-including the long awaited comparison of sequential and concomitant chemoradiation-were demonstrated.

[New aspects of current therapeutic strategies in oropharyngeal carcinoma: highlights of the 2012 ASCO meeting]

Beside the surgical treatment of head and neck cancer, the concept of organ and function preserving therapy of locally advanced HNSCC (head and neck squamous cell carcinoma) especially of oropharyngeal origin is becoming increasingly important. The comparison of induction chemotherapy plus chemoradiation and primary concomitant chemoradiation has recently been the subject of randomized clinical trials. New combinations of different (chemo)radiation regimens and targeted therapies are also under investigation for HNSCC. Molecular markers predicting treatment efficacy as well as new potential targets are also being evaluated in several clinical trials. The good prognosis of HPV-associated HNSCC has sparked efforts to deintensify treatment to minimize therapy-related toxicities. The impact of specific therapies is growing due to the increasing incidence of young patients with HPV-positive carcinomas.

Current treatment options for recurrent/metastatic head and neck cancer: a post-ASCO 2011 update and review of last year's literature

The majority of patients with a squamous cell carcinoma of the head and neck present with locally advanced tumors. The first-line treatment of locally advanced tumor stages consists of a combined modality management. Despite these aggressive protocols, many patients develop locoregional recurrences or metastasis and place particularly high demands on the interdisciplinary treatment team. Treatment with a curative intent must be differentiated from a palliative one. In addition to prior treatment, resectability, age and performance status, patient wishes must be taken into consideration in treatment planning, especially considering that most therapies offer little to no overall survival benefit. Salvage surgery, chemo- and target therapies, and reirradiation are head and neck surgeon's and radiooncologist's weapons in the fight against these strong opponents. This review focuses on publications and meeting news from last year and reviews the current status of the clinical application of each treatment modality in recurrent or metastatic head and neck cancer.

Expression of the serpin serine protease inhibitor 6 protects dendritic cells from cytotoxic T lymphocyte-induced apoptosis: differential modulation by T helper type 1 and type 2 cells

Dendritic cells (DCs) play a central role in the immune system as they drive activation of T lymphocytes by cognate interactions. However, as DCs express high levels of major histocompatibility complex class I, this intimate contact may also result in elimination of DCs by activated cytotoxic T lymphocytes (CTLs) and thereby limit induction of immunity. We show here that immature DCs are indeed susceptible to CTL-induced killing, but become resistant upon maturation with anti-CD40 or lipopolysaccharide. Protection is achieved by expression of serine protease inhibitor (SPI)-6, a member of the serpin family that specifically inactivates granzyme B and thereby blocks CTL-induced apoptosis. Anti-CD40 and LPS-induced SPI-6 expression is sustained for long periods of time, suggesting a role for SPI-6 in the longevity of DCs. Importantly, T helper 1 cells, which mature DCs and boost CTL immunity, induce SPI-6 expression and subsequent DC resistance. In contrast, T helper 2 cells neither induce SPI-6 nor convey protection, despite the fact that they trigger DC maturation with comparable efficiency. Our data identify SPI-6 as a novel marker for DC function, which protects DCs against CTL-induced apoptosis.

Two-dimensional 1H-, 13C-, and 31P-nuclear magnetic resonance and molecular-mechanics investigation of D-fructose 2,6-bisphosphate

Two-dimensional nuclear magnetic resonance studies have been carried out to assign unequivocally all the proton, carbon, and phosphorus resonances of D-fructofuranose 2,6-bisphosphate (1) and to verify its structure using a 400-MHz spectrometer. Several unexpected chemical-shift values and coupling constants were obtained. Molecular mechanics calculations (Sybyl) carried out to minimize the conformational energy of 1 yield phi C-1,P-2 = + 84, phi C-3,P-2 = - 155, and phi C-5,P-6 = + 175. Thus the unusual near-gauche orientations of C-1 and C-3 to P-2 in 1 can explain their small vicinal coupling constants (3JC-1,P-2 = 1.2, and 3JC-3,P-2 = 3.8 Hz), in contrast to the expected larger value seen for 3JC-5,P-6 namely, 6.9 Hz. Treatment of a sample of this compound with sodium borohydride did not affect its nuclear magnetic resonance spectrum, substantiating that O-2 is phosphorylated. Oxidation with sodium periodate yielded an intermediate which decomposed by a beta-elimination mechanism involving the 6-phosphate group. These data establish unequivocally the 1H, 13C, and 31P assignments and explain the observed anomalous shifts. Moreover they indicate that the activator of fructose 6-phosphate 1-kinase is the beta anomer of the 4T3 conformer of D-fructose 2,6-bisphosphate.