Interleukin 33 supports squamous cell carcinoma growth via a dual effect on tumour proliferation, migration and invasion, and T cell activation.

Interleukin (IL)-33 is an important cytokine in the tumour microenvironment; it is known to promote the growth and metastasis of solid cancers, such as gastric, colorectal, ovarian and breast cancer. Our group demonstrated that the IL-33/ST2 pathway enhances the development of squamous cell carcinoma (SCC). Conversely, other researchers have reported that IL-33 inhibits tumour progression. In addition, the crosstalk between IL-33, cancer cells and immune cells in SCC remains unknown. The aim of this study was to investigate the effect of IL-33 on the biology of head and neck SCC lines and to evaluate the impact of IL-33 neutralisation on the T cell response in a preclinical model of SCC. First, we identified epithelial and peritumoural cells as a major local source of IL-33 in human SCC samples. Next, in vitro experiments demonstrated that the addition of IL-33 significantly increased the proliferative index, motility and invasiveness of SCC-25 cells, and downregulated MYC gene expression in SCC cell lines. Finally, IL-33 blockade significantly delayed SCC growth and led to a marked decrease in the severity of skin lesions. Importantly, anti-IL-33 monoclonal antibody therapy increase the percentage of CD4+IFNγ+ T cells and decreased CD4+ and CD8+ T cells secreting IL-4 in tumour-draining lymph nodes. Together, these data suggest that the IL-33/ST2 pathway may be involved in the crosstalk between the tumour and immune cells by modulating the phenotype of head and neck SCC and T cell activity. IL-33 neutralisation may offer a novel therapeutic strategy for SCC.

An Introduction to the Relationship Between Lewis x and Malignancy Mainly Related to Breast Cancer and Head Neck Squamous Cell Carcinoma (HNSCC).

Lewis x functions as an adhesion molecule in glycolipids and glycoproteins since it mediates homophilic and heterophilic attachment of normal and tumoral cells. During malignancy, altered glycosylation is a frequent event; accumulating data support the expression of Lewis x in tumors although controversial results have been described including its relationship with patient survival. This report has been developed as an introduction to the relationship between Lewis x expression and breast cancer and head and neck squamous cell carcinoma (HNSCC). Results obtained in our laboratory are presented in the context of the literature.

Anti-PD-1/L1-associated immune-related adverse events as harbinger of favorable clinical outcome: systematic review and meta-analysis.

BACKGROUND: Recent studies have observed an association between immune-related adverse events (irAE) and favorable clinical outcomes in the setting of cancer treatment with immune checkpoint inhibitors (ICI). However, results have been variable and inconclusive. Therefore, we have conducted a pan-cancer meta-analysis evaluating the relationship between irAEs and clinical outcomes. MATERIALS AND METHODS: The search included studies published in PubMed, Embase, and Web of Science from conception to 12.28.2019 as well as abstracts published in the ASCO and ESMO meetings from 2015 to 2019. Studies were included if ICI was used in advanced or metastatic cancer settings and excluded if data contained only combination therapy regimens or contained anti-CTLA-4. Raw data for overall response rate (ORR), hazard ratios (HR), number of patients (n), and p values for overall survival (OS) and progression-free survival (PFS) were extracted. Pooled sensitivity (SN), specificity (SP), positive (PPV) and negative predictive values (NPV), and odds ratios (ORs) were calculated using the 2 × 2 table and logit transformed proportions; and summary receiver operating curve (sROC) was generated using the bivariate approach for ORR. Pooled HRs were calculated using the means weighted by inverse of the variance for OS and PFS. Heterogeneity was assumed and random effects model was used throughout the analyses. RESULTS: Final analysis included 32 studies, among which ORR data were available in 15 studies, OS in 17, and PFS in 16. 17 studies evaluated non-small cell lung cancer (NSCLC), two studies melanoma, one study gastric cancer, three studies renal cell carcinoma (RCC), seven studies various cancer types, two studies urothelial carcinoma, and one study head and neck cancer (HNSCC). With respect to ORR, pooled SN, SP, PPV and NPV, and OR were 0.522 [0.423-0.619], 0.810 [0.771-0.844], 0.516 [0.413-0.618], 0.819 [0.764-0.864], and 4.59 [3.24-6.50], respectively. The area under the curve (AUC) derived from the sROC was 0.773. HR for OS and PFS were 0.47 [95% CI 0.37-0.60] and 0.46 [95% CI 0.37-0.56], respectively. Between-study publication bias was present for ORR, OS, and PFS; however, results remained significant after trim-fill analysis. CONCLUSION: irAEs predict OR, OS, and PFS across different types of cancer and may represent useful biomarkers in the clinical setting.

Immune status and the efficacy of adjuvant radiotherapy for patients with localized Merkel cell carcinoma of the head and neck.

PURPOSE: Immunosuppressed (IS) patients are at increased risk for developing Merkel cell carcinoma (MCC) with worsened outcomes compared to immunocompetent (IC) patients. We sought to determine the effects of immune status on the efficacy of adjuvant RT regarding OS for patients with stage I, II or III (localized) MCC of the head and neck. METHODS/PATIENTS: The National Cancer Database was queried for patients with resected, localized MCC of the head and neck with known immune status. Kaplan-Meier methods were used to describe OS. Log-rank tests, multivariable Cox regression models and interaction effect testing were used to compare OS by subgroup categorized by patient and treatment factors including immune status and adjuvant RT receipt. RESULTS: A total of 892 (89.6%) IC and 104 (10.4%) IS patients with MCC of the head and neck were included. Adjuvant RT was associated with improved 3-year OS rate for both IS patients (49.4% vs. 35.5%, p = 0.0467) and stage I/II IC patients (72.4% vs. 62.9%, p = 0.0092). Adjuvant RT was associated with decreased hazard of death (HR 0.77, 95% CI 0.62-0.95). Interaction effect testing did not demonstrate a difference in the efficacy of adjuvant RT on OS between IC and IS status (p = 0.157). CONCLUSIONS: In this NCDB analysis, adjuvant RT was associated with decreased hazard of death for patients with localized MCC of the head and neck regardless of immune status and should be considered for both IS and IC patients.

Is photobiomodulation therapy effective in reducing pain caused by toxicities related to head and neck cancer treatment? A systematic review.

Photobiomodulation therapy (PBMT) has been considered an effective method for preventing and managing certain cancer-related toxicities in head and neck cancer (HNC) patients treated with radiotherapy and chemotherapy. However, the potential effects of PBMT on pain control and analgesia resulting from these toxicities is still controversial. The aim of this systematic review was to compile available evidence of the effects of PMBT on pain control and reduced use of analgesics in HNC patients. We searched three indexed databases: MEDLINE/PubMed, Embase, and Scopus. The databases were reviewed up to and including December 2018. Only human clinical studies in English language were selected. Information was only available for mucositis and radiodermatitis. Fifteen out of 1112 studies met the inclusion criteria (14 for oral mucositis (OM) and 1 for radiodermatitis). From the 14 studies involving the prevention and treatment of OM, 10 had the study subjects compared to a placebo group. Of these 10 studies, all but 1 showed statistically significant difference related to pain control favoring the PBMT group. The study that compared PBMT with other treatment modality showed better results in pain control with PBMT. It appears that PBMT application frequency and potency impact on pain control. The only study involving the prevention and treatment of radiodermatitis was compared to placebo arm and showed statistically significant difference related to pain control favoring the PBMT group. Seven studies compared the need of analgesic medication between PBMT and placebo groups. Of these, five studies showed that the use of analgesic medication was significantly higher in the placebo group. The current evidence supports that PBMT is effective in pain control resulting from OM and radiodermatitis and may also reduce the need for analgesics. The evidence is not yet available of the effects of PBMT in other HNC treatment-related toxicities.

Non-murine models to investigate tumor-immune interactions in head and neck cancer.

The immune response has important roles in the biology of solid tumors, including oncogenesis, tumor growth, invasion and metastasis, and response to treatment. Improved understanding of tumor-immune system interactions has provided promising therapeutic options that are based on the rescue and enhancement of the anti-tumoral host response. Immune-based treatments have been approved for clinical use in various types of cancer, including head and neck cancer (HNC); other strategies involving combination therapies are currently in development. These novel therapies were developed based on knowledge derived from in vitro, in silico, and in vivo pre-clinical studies. However, clinical trials seldom replicate the efficacy observed in pre-clinical animal studies. This lack of correlation between pre-clinical studies and clinical trials may be related to limitations of the models used; which highlights the relevance of considering immune-related aspects of different pre-clinical models. Murine models are the most frequently used pre-clinical models of HNC and are discussed elsewhere. Non-murine models have characteristics that offer unique opportunities for the study of HNC etiology, therapeutic strategies, and tumor-immune system interactions. The current review focuses on immune-related aspects of non-murine models, including dog, cat, pig, zebrafish, and frog, that could be used to investigate tumor-immune interactions in HNC.

Immune-relevant aspects of murine models of head and neck cancer.

Head and neck cancers (HNCs) cause significant mortality and morbidity. There have been few advances in therapeutic management of HNC in the past 4 to 5 decades, which support the need for studies focusing on HNC biology. In recent years, increased recognition of the relevance of the host response in cancer progression has led to novel therapeutic strategies and putative biomarkers of tumor aggressiveness. However, tumor-immune interactions are highly complex and vary with cancer type. Pre-clinical, in vivo models represent an important and necessary step in understanding biological processes involved in development, progression and treatment of HNC. Rodents (mice, rats, hamsters) are the most frequently used animal models in HNC research. The relevance and utility of information generated by studies in murine models is unquestionable, but it is also limited in application to tumor-immune interactions. In this review, we present information regarding the immune-specific characteristics of the murine models most commonly used in HNC research, including immunocompromised and immunocompetent animals. The particular characteristics of xenograft, chemically induced, syngeneic, transgenic, and humanized models are discussed in order to provide context and insight for researchers interested in the in vivo study of tumor-immune interactions in HNC.

Bloodstream infection in patients with head and neck cancer: a major challenge in the cetuximab era.

PURPOSE: To assess the impact of bloodstream infection (BSI) in patients with head and neck cancer (HNC) in the cetuximab era. METHODS: We prospectively analysed the epidemiology, microbiology and outcomes of 51 BSI episodes occurring in 48 patients with HNC (2006-2017). We performed a retrospective matched-cohort study (1:2) to determine the risk factors for BSI. Finally, we compared patients who died with those who survived to identify risk factors for mortality. RESULTS: The most frequent HNC localization was the oropharynx (43%), and pneumonia was the most frequent source (25%). Gram-positive BSI occurred in 55% cases, mainly due to Streptococcus pneumoniae (21%), and among Gram-negatives, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae were the most frequent. Hypoalbuminemia (OR 8.4; 95% CI, 3.5-19.9), previous chemotherapy (OR, 3.2; 95% CI, 1.3-7.4) and cetuximab therapy (OR, 2.8; 95% CI, 1.6-6.7) were significant risk factors for BSI. Patients with BSI had a higher overall case-fatality rate than patients without BSI (OR, 4.4; 95% CI, 1.7-11.8). Hypoalbuminemia was an independent risk factor for the early (7 day) and overall (30 day) case-fatalities, with ORs of 0.8 (95% CI, 0.6-0.9) and 0.8 (95% CI, 0.7-0.97), respectively. The presence of comorbidities (OR, 7; 95% CI, 1.4-34) was also an independent risk factor for overall case-fatality. CONCLUSIONS: BSI causes high mortality in patients with HNC and is most often secondary to pneumonia. It occurs mainly among patients with hypoalbuminemia who receive treatment with cetuximab or chemotherapy. The development of BSI in patients with HNC impairs their outcome, especially in the presence of hypoalbuminemia and comorbidities.

Macrophages and prognosis of oral squamous cell carcinoma: A systematic review.

Oral Squamous Cell Carcinoma (OSCC) presents a tumor microenvironment rich in inflammatory cells. Depending on the stimulus, macrophages can polarize in M1 or M2 profile, where M1 acts as proinflammatory and antitumor, and M2 is anti-inflammatory and shows protumor activity. Several studies have shown that macrophages are important to the prognosis of patients with different types of cancer. Our aim was to conduct a systematic review to evaluate the role of macrophages in the prognosis of OSCC patients. A search in the Pubmed, Scopus, and ISI Web of Knowledge database was performed, and it was included only studies that evaluated the importance of macrophages in the prognosis of OSCC patients. From initial 286 articles, 14 fully attended the inclusion criteria. In the majority of the articles, it was evaluated only CD68, a panmacrophage marker, or CD163, a M2 marker. Only one article evaluated the M1 marker, CD11c. Besides, 5 articles analyzed the presence of macrophages in different areas of the tumor. Higher concentrations of CD68 and CD163 were associated with worse survival. In conclusion, macrophages are important to OSCC patients' prognosis; however, it is necessary to address in which tumor region the presence of polarized macrophage is more important to the outcome.

A decreased peritumoral CD1a+ cell number predicts a worse prognosis in oral squamous cell carcinoma.

AIMS: Dendritic cells (DCs) are known to play a central role in the regulation of both innate and adaptive immunological responses, including antitumour immunity. The aim of this study was to evaluate the prognostic impact of intratumoral and peritumoral DCs in oral squamous cell carcinoma (OSCC) affecting the tongue and floor of the mouth. METHODS AND RESULTS: Immunohistochemistry for CD1a and CD83 was performed in 53 patients with OSCC in the tongue and floor of the mouth. The markers were evaluated by automated examination in intratumoral and peritumoral compartments, and the results were expressed as density of cells/mm2 . Correlations between these data and clinicopathological and survival outcomes were investigated. Depletion of peritumoral CD1a+ cells was associated with lymph node metastasis (P = 0.05), whereas depletion of peritumoral CD83+ cells was correlated with smoking history (P = 0.04), lymph node metastasis (P = 0.015), and extracapsular spread of lymph nodes (P = 0.018). Peritumoral CD1a+ was correlated with recurrence (P = 0.007) and overall survival (P = 0.03). The results of the survival analysis with the Cox proportional hazard model showed that depletion of peritumoral CD1a+ cells is an independent factor associated with overall survival and disease-free survival. CONCLUSION: Our results suggest that depletion of peritumoral CD1a+ cells is a strong independent prognostic factor, predicting a higher recurrence rates and worse survival outcomes.

Role of Immunotherapy in Head and Neck Cancer.

Immune system dysfunction plays a role in both the development and progression of head and neck squamous cell carcinoma (HNSCC), highlighting the potential role for immunotherapy to improve outcomes in this disease. The application of anti-PD-1 therapies for recurrent or metastatic HNSCC has found promising results. This has led to interest in combining immunotherapy with radiation therapy (RT) for the primary treatment of locally advanced HNSCC. RT with concurrent cetuximab is an option for patients who are medically unfit to receive cisplatin, and ongoing trials seek to determine to role of cetuximab-RT in treatment de-intensification for HPV+ oropharyngeal HNSCC. Other ongoing trials are evaluating the use of anti-PD-1 and anti-PD-L1 therapies in the upfront setting for newly diagnosed high-risk, locally advanced HNSCC, in an effort to improve disease control. Finally, early phase I studies are now investigating the use of anti-PD-1 therapy in conjunction with RT for refractory recurrent or metastatic HNSCC.

Role of tumour-associated macrophages in oral squamous cells carcinoma progression: an update on current knowledge.

BACKGROUND: Oral squamous cell carcinoma (OSCC) accounts over 90% of malignant neoplasms of the oral cavity. This pathological entity is associated to a high mortality rate that has remained unchanged over the past decades. Tumour-associated macrophages (TAMs) are believed to have potential involvement in OSCC progression. However, the molecular networks involved in communication between stroma and cancer cells have not yet been fully elucidated. MAIN BODY: The role of M2 polarized cells in oral carcinogenesis is supported by a correlation between TAMs accumulation into OSCC stroma and poor clinical outcome. Signalling pathways such as the NF-κB and cytokines released in the tumour microenvironment promote a bidirectional cross-talk between M2 and OSCC cells. These interactions consequently result in an increased proliferation of malignant cells and enhances aggressiveness, thus reducing patients' survival time. CONCLUSIONS: Here, we present a comprehensive review of the role of interleukin (IL)-1, IL-4, IL-6, IL-8, IL-10 and the receptor tyrosine kinase Axl in macrophage polarization to an M2 phenotype and OSCC progression. Understanding the molecular basis of oral carcinogenesis and metastatic spread of OSCC would promote the development of targeted treatment contributing to a more favourable prognosis.

Immunohistochemical expression of DNA methyltransferases 1, 3a, and 3b in actinic cheilitis and lip squamous cell carcinomas.

BACKGROUND: Epigenetic modifications, including DNA methylation of tumor suppressor genes carried out by DNA methyltransferases (DNMTs), are important events in carcinogenesis. Although there are studies concerning to its expression in several cancer types, DNMTs expression pattern is not known in photoinduced lip carcinogenesis. The aim of this study was to investigate the immunoexpression of DNMTs 1, 3a, and 3b in lip precancerous lesion (actinic cheilitis) and cancer. METHODS: Thirty cases of actinic cheilitis (AC), thirty cases of lip squamous cell carcinoma (LSCC), and twenty cases of non-neoplastic tissue (NNT) were selected for immunohistochemical investigation of DNMTs 1, 3a, and 3b. RESULTS: Nuclear DNMT 1 immunoreactivity was significantly higher in the LSCC group (68.6%) compared with NNT (47%), and nuclear DNMT 3b was higher in LSCC (70.9%) than in NNT (37.9%) and in AC (44%). Only DNMT 3a showed both higher nuclear and cytoplasmic expression in AC (35.9% and 35.5%, respectively) than in NNT (4.4% and 16.1%, respectively) and LSCC (8.8% and 13.2%, respectively) (P < 0.05). CONCLUSIONS: The results suggested that DNMT 3a could play a key role in the methylation process of initial steps of UV carcinogenesis present in AC while DNMT 3b could be responsible for de novo methylation in already established lip cancer.

mTOR pathway protein immunoexpression as a prognostic factor for survival in head and neck cancer patients: a systematic review and meta-analysis.

BACKGROUND: Several mTOR pathway proteins are involved in the regulation of cellular anabolism, growth, proliferation, and survival. Activated proteins in the mTOR pathway are deregulated in multiple types of cancers and could influence prognosis. However, it is unclear whether deregulation of mTOR pathway proteins serves a prognostic role in patients with head and neck cancer (HNC). Furthermore, proteins in the mTOR pathway may be important targets for anticancer therapy. The aim of this study was to summarize existing cohort studies to determine whether immunoexpression of mTOR pathway proteins are important prognostic factors for survival in patients with HNC. MATERIALS AND METHODS: A systematic review was performed using the Cochrane, Lilacs, PubMed, ScienceDirect, Scopus, and Web of Science databases (up to 23 January 2015). A meta-analysis was conducted to measure the frequency of protein expression in head and neck cancer patient samples and the prognostic value of mTOR pathway proteins for overall survival (OS) and disease-free survival (DFS). RESULTS: Twelve studies were included in our final analysis. The meta-analysis revealed that the frequency of overall expression of mTOR pathway proteins was 74.42% (CI: 63.3 to 84.0, P < 0.001, n = 2016 samples). The survival meta-analysis showed a pooled hazard ratio for OS and DFS of 1.44 (95% confidence interval [95% CI] 1.14-1.73) and 1.18 (95% CI 0.71-1.64), respectively. CONCLUSION: This systematic review and meta-analysis support evidence that mTOR pathway proteins can be used as predictive markers for survival in patients with HNC because their expression was significantly associated with poor OS and short DFS.

Immunology and Immunotherapy of Head and Neck Cancer.

The immune system plays a key role in the development, establishment, and progression of head and neck squamous cell carcinoma (HNSCC). A greater understanding of the dysregulation and evasion of the immune system in the evolution and progression of HNSCC provides the basis for improved therapies and outcomes for patients. HNSCC cells evade the host immune system through manipulation of their own immunogenicity, production of immunosuppressive mediators, and promotion of immunomodulatory cell types. Through the tumor's influence on the microenvironment, the immune system can be exploited to promote metastasis, angiogenesis, and growth. This article provides a brief overview of key components of the immune infiltrating cells in the tumor microenvironment, reviewing immunological principles related to head and neck cancer, including the concept of cancer immunosurveillance and immune escape. Current immunotherapeutic strategies and emerging results from ongoing clinical trials are presented.

Immunohistochemical subtypes of diffuse large B-cell lymphoma in the head and neck region.

The objectives of this study were to detect immunohistochemical subtypes of diffuse large B-cell lymphoma (DLBCL) of the head and neck, to compare the Hans, Choi, and Tally algorithms and to examine the significance of protein expression in these algorithms. This study included 103 DLBCL patients at Sichuan Cancer Hospital between May 2010 and October 2012. Immunohistochemistry was per-formed for CD10, B-cell lymphoma 6 protein (Bcl-6), mutated melanoma-associated antigen 1 (MUM1), germinal center B-cell-expressed transcript 1 (GCET1), forkhead box protein P1 (FOXP1), and LIM do-main only 2 (LMO2). Subtypes were determined according to the Hans, Choi, and Tally algorithms. Positive staining for CD10 was detected in 16 patients (15.53%), for Bcl-6 in 68 patients (66.02%), for MUM1 in 69 patients (66.99%), for GCET1 in 21 patients (20.39%), for FOXP1 in 75 patients (72.82%), and for LMO2 in 50 patients (48.54%). The Hans algorithm identified 26 patients (25.2%) with the germinal center B-cell (GCB) subtype and 77 (74.8%) with the activated B-cell (ABC) subtype. In the Choi algorithm, 25 patients (24.3%) were identified with the GCB subtype and 78 (75.7%) with the ABC subtype. In the Tally algorithm, 20 patients (19.4%) had the GCB subtype and 83 (80.6%) had the ABC subtype. Expression of CD10, MUM1, GCET1, FOXP1, and LMO2 correlated with algorithm (P < 0.05); however, Bcl-6 did not correlate with the Hans and Choi algorithms. DLBCL of the head and neck is most commonly the ABC subtype, not GCB. The Hans, Choi, and Tally algorithms were not significantly different.

Infiltrating CD57+ inflammatory cells in head and neck squamous cell carcinoma: clinicopathological analysis and prognostic significance.

This study investigated the immunodetection of CD57+ inflammatory cells in patients with head and neck squamous cell carcinoma (HNSCC) and its association with clinicopathological parameters and overall survival. Data collected from the morphological analysis and immunohistochemical reaction testing of archived HNSCC specimens (n=70) were statistically analyzed by bivariate and multivariate statistical testing at a significance level of P<0.05. The results indicate that CD57+ inflammatory cells predominate within the peritumoral stroma of HNSCC lesions and the existence of two significant relationships: between high CD57+ cell density and the development of a tumor of a large size [odds ratio (OR)=5.610, 95% confidence interval (CI)=1.516-20.763) and between high CD57+ cell density and the development of locoregional metastatic disease (OR=3.401, 95% CI=1.162-9.951). A significant difference in the rate of survival was detected only in HNSCC patients that presented large size tumors (OR=4.747, 95% CI=1.281-17.594). Together, these results suggest that although high CD57+ inflammatory cell density is associated with HNSCC lesions of greater clinical severity, the variable of cell density is not an independent predictor of HNSCC patient survival. Our findings also suggest that the relatively aggressive infiltration of CD57+ inflammatory cells in the peritumoral stroma of head and neck carcinomas may contribute to an ineffective locoregional antitumoral response.

Trifunctional antibodies induce efficient antitumour activity with immune cells from head and neck squamous cell carcinoma patients after radio-chemotherapy treatment.

BACKGROUND Trifunctional antibodies, such as catumaxomab (anti-EpCAM×anti-CD3) and ertumaxomab (anti- HER-2/neu×anti-CD3), transiently link immune effector cells to tumour cells, which results in cellular cytotoxicity towards the tumour cells. A functional immune system is therefore essential for effective anti-tumour activity. However, the commonly observed haematotoxicity of chemotherapeutics and radiation therapy may be associated with some degree of immunosuppression. Combining chemotherapy and trifunctional antibodies in cancer treatment requires understanding of the impact of chemotherapeutics on immune cell function and, thus, on the activity of trifunctional antibodies. METHODS The effect of chemotherapeutic treatment on trifunctional antibody-mediated anti-tumour activity was assessed in vitro. Blood samples were collected from 12 head and neck squamous cell carcinoma patients after chemotherapy (5-fluorouracil, cisplatin) and radiotherapy, and from one healthy control donor. The immune cell status was analysed and mononuclear cells (MNC) were isolated. The potency of catumaxomab and ertumaxomab was assessed in a cytotoxicity assay using MNC isolated from each patient sample in co-culture with a tumour target cell line. The release of infl ammatory cytokines was also monitored in the cell culture supernatant. RESULTS Most patients included in this study had decreased immune cell counts during the course of chemotherapy. Nonetheless, an effective and concentration-dependent anti- tumour activity mediated by trifunctional antibodies was demonstrated using these patient immune effector cells. The immune response activity of the patient immune cells was not impaired one week after cisplatin administration or even three days after the last 5-fluorouracil treatment. CONCLUSION This study shows for the first time that immune effector cells from cancer patients undergoing standard chemotherapy and radiotherapy can be activated by trifunctional antibodies for efficient killing of tumour cells.

Response of peripheral blood mononuclear cells to conditioned medium from cultured oral squamous cell carcinomas.

The current study investigated the capacity for tumor factors secreted by head and neck squamous cell carcinoma (HNSCC) cell lines, KB, KB16, and HEP, to induce the secretion of various cytokines from peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from blood samples collected from six healthy volunteers and these cells were incubated for 6, 24, 48, or 72 hours in the presence of 50% conditioned medium collected from cultured cell lines pretreated with, or without, stimulants such as phytohemagglutinin (PHA) or lipopolysaccharides (LPS). Aliquots of each supernatant were then assayed for levels of IFN-Γ, vascular endothelial growth factor (VEGF), TNF-α, and IL-4 using enzyme linked immunosorbent assays (ELISAs). Data collected were analyzed using Student's t-test, an ANOVA test followed by Tukey's test, and tests of Pearson's Correlation. PBMCs cultured with KB16-conditioned medium produced the highest levels of IFN-Γ. VEGF was also detected in conditioned media collected from all of the squamous cell carcinoma (SCC) cell lines used, and a significant difference in VEGF levels between control and KB- or KB16-conditioned media was observed. TNF-α was secreted by all PBMC groups within 6 hours of receiving conditioned media, and these levels increased up to the 24 hour timepoint, after which levels of TNF-α stabilized. In contrast, none of the supernatant samples contained detectable levels of IL-4. In combination, these data suggest that direct contact between fresh human PBMCs and conditioned media from tumor cells induces the secretion of TNF-α and VEGF by PBMCs, and this represents an initial angiogenic response.