Contribution of serum inhibitory factors and immune cellular defects to the depressed cell-mediated immunity in patients with head and neck cancer

Transient immunological and clinical effectiveness of treating mice bearing premalignant oral lesions with PD-1 antibodies

A carcinogen-induced premalignant oral lesion model that progresses to oral cancer was used to examine the impact of blocking PD-1 on cytokine expression and on progression of lesions to cancer. The results of this study show increased production of IL-2 and the inflammatory cytokines IL-6, IL-17 and TNF-α by spleen cells of lesion-bearing mice that were treated with PD-1 antibody for 1 week compared to cytokine production by spleen cells of lesion-bearing mice treated with control antibody. Production of IFN-γ increased at 3 weeks of PD-1 antibody treatment, although production of the other Th1 and inflammatory mediators declined. By 5 weeks, levels of these cytokines declined for both control and PD-1 antibody-treated mice. Flow cytometric analysis for IFN-γ-expressing cells showed shifts in CD4⁺ cells expressing IFN-γ consistent with the changes in cytokine secretion. Whether or not treatment generated reactivity to lesions or HNSCC was determined. Spleen cells from PD-1 antibody-treated mice were stimulated by lysates of premalignant lesion and HNSCC tongue tissues to produce increased levels of Th1 and select inflammatory cytokines early in the course of PD-1 antibody treatment. However, with continued treatment, reactivity to lesion and HNSCC lysates declined. Analysis of clinical response to treatment suggested an early delay in lesion progression but, with continued treatment, lesions in PD-1 antibody-treated mice progressed to the same degree as in control antibody-treated mice. Overall, these results show an early beneficial response to PD-1 antibody treatment, which then fails with continued treatment and lesion progression.

Impact of head and neck malignancies on risk factors and survival in systemic lupus erythematosus

CONCLUSIONS

Systemic lupus erythematosus (SLE) is associated with an increased risk of developing a head and neck malignancy (HNM). A history of SLE did not significantly impact the survival of our study cohort after cancer developed.

OBJECTIVES

To examine the risk and survival rates of HNM in patients with SLE.

METHODS

This was a population-based, retrospective cohort study. We compared patients newly diagnosed with SLE between 2001 and 2008 (n = 8751) with age-matched controls (1:10) (n = 87 510). The incidence of HNMs at the end of 2009 was then determined.

RESULTS

We found a 2.16-fold higher risk of HNMs in patients diagnosed with SLE compared with the risk of first malignancy in the age-matched controls (incidence rate ratio, IRR = 2.16, p < 0.05). The site with the highest incidence of HNMs in SLE patients was the oral cavity (5/11, 45.45%), followed by the nasopharynx (4/11, 36.36%). SLE displayed no synergic effect on the survival of SLE patients with an HNM compared with age-matched controls with a new HNM (p = 0.2446).

Evaluation of humoral immunity in oral cancer patients from a nigerian referral centre

The immune system is central in the body's defense against non-self. Immunoglobulins and acute phase proteins have been reported to play active roles in carcinogenesis. This prospective longitudinal study was carried out to determine the state of humoral immunity in Nigerian oral cancer patients relative to controls. Twenty newly diagnosed untreated cases of oral squamous cell carcinoma recruited from our centre were included in the study. The controls included 20 apparently healthy and HIV negative volunteers. Serum immunoglobulin classes and acute phase proteins were measured using immunoplates. IgA and ceruloplasmin showed statistically significantly elevated levels in the patients compared with controls, while increases in IgM and IgG were insignificant. The raised levels suggest a role for immunoglobulin A and ceruloplasmin in the mechanisms involved in oral cancers. Findings from this study are similar to that reported elsewhere in the literature. Further work is needed to ascertain the role and usefulness of immunoglobulins and acute phase proteins in staging, disease monitoring, therapy and prognostication.

Spliceosome-mediated RNA trans-splicing facilitates targeted delivery of suicide genes to cancer cells

Patients suffering from recessive dystrophic epidermolysis bullosa (RDEB), a hereditary blistering disease of epithelia, show susceptibility to develop highly aggressive squamous cell carcinoma (SCC). Tumors metastasize early and are associated with mortality in the 30th-40th years of life in this patient group. So far, no adequate therapy is available for RDEB SCC. An approach is suicide gene therapy, in which a cell death-inducing agent is introduced to cancer cells. However, lack of specificity has constrained clinical application of this modality. Therefore, we used spliceosome-mediated RNA trans-splicing technology, capable of replacing a tumor-specific transcript with one encoding a cell death-inducing peptide/toxin, to provide tumor-restricted expression. We designed 3' pre-trans-splicing molecules (PTM) and evaluated their efficiency to trans-splice an RDEB SCC-associated target gene, the matrix metalloproteinase-9 (MMP9), in a fluorescence-based test system. A highly efficient PTM was further adapted to insert the toxin streptolysin O (SLO) of Streptococcus pyogenes into the MMP9 gene. Transfection of RDEB SCC cells with the SLO-PTM resulted in cell death and induction of toxin function restricted to RDEB SCC cells. Thus, RNA trans-splicing is a suicide gene therapy approach with increased specificity to treat highly malignant SCC tumors.

The current state of head and neck cancer gene therapy

The incidence of head and neck cancer continues to increase worldwide, with tobacco exposure and human papillomavirus type 16 infections being the major etiological factors. Current therapeutic options are ineffective in approximately half of the individuals afflicted with this malignancy. Developments in the identification of molecules that sustain head and neck squamous cell carcinoma (HNSCC) growth and survival have made molecular targeting by gene therapy approaches a feasible therapeutic strategy. Although gene therapy was originally designed to correct single gene defects, it has now evolved to encompass all forms of therapeutic interventions involving engineered cells and nucleic acids that modify the overall pattern of gene expression within target tissues. Several preclinical studies and clinical trials have tested the efficacy of targeting specific molecules in patients with HNSCC, using genetic therapy approaches. This review discusses promising preclinical and clinical approaches and new directions for HNSCC gene therapy.

Soluble Ig-like transcript 3 inhibits tumor allograft rejection in humanized SCID mice and T cell responses in cancer patients

Attempts to enhance patients' immune responses to malignancies have been largely unsuccessful. We now describe an immune-escape mechanism mediated by the inhibitory receptor Ig-like transcript 3 (ILT3) that may be responsible for such failures. Using a humanized SCID mouse model, we demonstrate that soluble and membrane ILT3 induce CD8(+) T suppressor cells and prevent rejection of allogeneic tumor transplants. Furthermore, we found that patients with melanoma, and carcinomas of the colon, rectum, and pancreas produce the soluble ILT3 protein, which induces the differentiation of CD8(+) T suppressor cells and impairs T cell responses in MLC. These responses are restored by anti-ILT3 mAb or by depletion of soluble ILT3 from the serum. Immunohistochemical staining of biopsies from the tumors and metastatic lymph nodes suggests that CD68(+) tumor-associated macrophages represent the major source of soluble ILT3. Alternative splicing, resulting in the loss of the ILT3 transmembrane domain, may contribute to the release of ILT3 in the circulation. These data suggest that ILT3 depletion or blockade is crucial to the success of immunotherapy in cancer. In contrast, the inhibitory activity of soluble ILT3 on T cell alloreactivity in vitro and in vivo suggests the potential usefulness of rILT3 for immunosuppressive treatment of allograft recipients or patients with autoimmune diseases.

Immunological aspects of head and neck cancer: biology, pathophysiology and therapeutic mechanisms

Advanced cancer and head and neck cancer, in particular, remains a major clinical challenge with its associated morbidity and inevitable mortality. Local control of early disease is achievable in many solid tumours with current surgical and radiotherapeutic techniques but metastatic disease is associated with poor outcome and prognosis. It is known that, by the time of presentation, many patients will already have occult microscopic metastatic disease, and surgery and radiotherapy will not result in long-term survival. What little effect modern chemotherapeutic agents have on microscopic disease is, however, limited by systemic toxicity and multi-drug resistance. Immune surveillance is postulated to be operative in man. There is evidence, however, that patients with progressive tumour growth have failure of host defences both locally and systemically. Various possible defects and tumour escape mechanisms are discussed in the review. Immunotherapy and, in particular adoptive T cell therapy and DC therapy, show promise as putative tumour-specific therapy with clinical benefits. These techniques are undergoing development and evaluation in phase 1 clinical trials. Preliminary data suggest that the treatments are well tolerated. Unfortunately, there is limited evidence of significant and prolonged improvements in clinical outcome. Further developments of beneficial protocols (adjuvants, mode and frequency of vaccination etc) and multicentre studies of the use of immunotherapy in cancer are now required.

Expansion of natural killer cells in patients with head and neck cancer: detection of "noninhibitory" (activating) killer Ig-like receptors on circulating natural killer cells

BACKGROUND

In a group of patients with head and neck cancers (H&NC), the expansion of the population of CD3-,CD16+ natural killer (NK) cells in the peripheral blood was studied.

METHODS

Cytofluorimetric analysis of the expression of killer Ig-like receptors (KIR, namely p58.1, p58.2, p58.3, p70, and p140) and CD94-NKG2a was performed. Cytolytic activities were studied using 51Cr release assay. T and NK cell cloning was performed using limiting dilution culture conditions. Cytokine production was analyzed using commercial enzyme immunoassays.

RESULTS

Phenotypic analysis showed that the expanded populations were heterogeneous. Even in the presence of a large number of circulating NK cells, "nonspecific" cytolytic capacities were heavily reduced, whereas cytolytic capacity related to T cells was virtually normal. Unlike NK cell clones derived from healthy donors, most NK cells derived from H&NC patients expressed surface "activating" NK cell receptors (KAR) for HLA, detected by use of a redirected cytolytic assay. Analysis of the CD4+ subpopulation at the clonal level demonstrated that they had a severe proliferative defect.

CONCLUSION

These experimental data indicated that H&NC patients have a polyclonal expansion of functionally deficient NK cells expressing KAR. In addition, the proliferative capacity of patients' "helper" cells was strongly inhibited, thus accounting for a severe impairment of cytolytic activity of the expanded NK cells.

Effect of selenium on the immunocompetence of patients with head and neck cancer and on adoptive immunotherapy of early and established lesions

Supplementation with 200 microg/day of sodium selenite during therapy for squamous cell carcinoma (SQCC) of the head and neck, e.g., surgery, radiation, or surgery and radiation, resulted in a significantly enhanced cell-mediated immune responsiveness. The enhanced responsiveness was evident during therapy and following conclusion of therapy. In contrast, patients in the placebo arm of the study showed a decline in immune responsiveness during therapy. The results from studies on mice inoculated with SQCC cells expressing the receptor for interleukin-2 (IL-2) and supplemented with Se (2.00 ppm) indicated that Se significantly retards the clinical appearance of tumors; peritumoral injections of 2,000 IU of IL-2 resulted in 50% reduction in the size of established tumors and 72% of early tumors. The combined data suggested that local immunotherapy with IL-2 in hosts supplemented with Se may represent an effective modality of treatment for the prevention of recurrences at the site of conventionally treated primary tumors.

CD34+ immune suppressive cells in the peripheral blood of patients with head and neck cancer

Patients with head and neck squamous cell carcinoma (HNSCC) have profound defects in their immune defenses. Using immunofluorescent staining and flow cytometric analysis, we found that most patients with HNSCC have increased levels of CD34+ cells within their peripheral blood. These circulating CD34+ cells contribute to the depressed functional competence of the peripheral blood T-lymphocytes. This was demonstrated by the increased level of proliferative responsiveness to interleukin-2 by the patients' peripheral blood T-cells after depletion of CD34+ cells. These results show the importance of CD34+ cells in contributing to the depression of T-lymphocyte function in patients with HNSCC and suggest that strategies designed to reduce the levels of circulating CD34+ cells may enhance the immune reactivity of the patients' circulating T-lymphocytes against the HNSCC.

The immunopharmacology of head and neck cancer: an update

Patients with head and neck squamous cell cancer have cell-mediated immune defects and anergy, which progress with disease. T-lymphocytopenia and dysfunction, monocyte dysfunction, prostaglandins, antigen-antibody complexes, serum and cell suppressive factors, radiation therapy and poor nutrition with zinc deficiency all contribute. Nevertheless, cell-mediated immunoreactivity to tumor is manifest in the majority of the patient's blood and regional nodes, and in the tumor itself by tumor-infiltrating lymphocytes. Lymphocytes from these sources cloned in the presence of interleukin-2 +/- tumor extracts show relatively specific cytotoxicity against squamous cell cancer. Humoral immunity is intact, and increased IgA and IgE levels and antibodies reactive to tumor antigens are common. Tumor-associated antigens detected in serum and tumor include carcinoembryonic antigen, tumor polypeptide antigen, squamous cell cancer antigens, tumor antigen-4 and various mucin antigens. The mucin antigens, in particular, can elicit T-cell responses. Humoral reactivity to such antigens is manifest in circulating immune complexes and immunoglobulin coating of tumor surfaces. Immunotherapeutic efforts in head and neck squamous cell cancer should logically employ T-cell adjuvants, contrasuppression and immunorestoration. Non-specific stimulation with bacille Calmette-Guerin (BCG), levamisole and other agents has not been successful. Encouraging results have been observed in limited trials with indomethacin and plasmapheresis. Early trials with local administration of low dosages of interferon-alpha, natural interleukin-2 and a natural interleukin mixture have produced partial and complete regressions with no toxicity and with intense leukocyte infiltration indicating cellular immunity. Efforts are needed to define the mechanisms and the antigens involved in these reactions. On the contrary, treatments with high dosages of recombinant interferon-alpha and interleukin-2 have yielded few responses and considerable toxicity. Combination strategies are discussed which may improve upon these initial immunotherapeutic effects of these low dose trials.

Taxol pretreatment of tumor targets amplifies natural killer cell mediated lysis

Taxol is known to polymerize and stabilize microtubules and thereby alter many cellular functions. Our studies examined the effects of taxol pretreatment of tumor targets and cytotoxic effector cells in an effort to determine whether such treatment would result in increased tumor cell lysis without affecting cytotoxic cell function. Our studies demonstrated that taxol concentrations of 6-30 ng/ml which induced approximately 50% growth inhibition and > or = 50% block in the G2/M phase of the K562 cell targets did not have any significant effect on the functional ability of NK cells to lyse K562 cells. Pretreatment of K562 cells with taxol (6 and 30 ng/ml) resulted in an increase in K562 cell lysis by NK cells (or NK cells stimulated with 100 units/ml of rIL-2) in 7 out of 9 donors. The amplification of NK cell-mediated lysis of tumor targets due to taxol pretreatment may provide a combination therapeutic approach which includes taxol treatment followed by rIL-2 stimulation of the immune killer cell function.

A comparison of segmental and marginal bony resection for oral squamous cell carcinoma involving the mandible

PURPOSE

This study reviews the accuracy of preopertive diagnosis of mandibular invasion by oral squamous cell carcinoma and assesses the role of marginal resection of the mandible in its treatment.

PATIENTS AND METHODS

A retrospective study of a 5-year cohort of 46 patients who underwent mandibular resection for previously untreated oral squamous cell carcinoma was done. Data evaluated included age; sex; site and stage of cancer; preoperative clinical, panoramic, and computed tomography (CT) evaluations; and histologic findings on the resection specimen. The type of mandibular resection (segmental vs marginal) and treatment outcome also were compared.

RESULTS

Clinical examination, panoramic radiographs, and CT scans were 78.5% to 82.6% accurate in diagnosing mandibular invasion by squamous carcinoma. Clinical examination and panoramic radiographs are more sensitive than CT scans (86.6% vs 53%), but CT scans were more specific (92.5% vs 80%). The mandible was involved in 65% of patients with segmental resection and 7.6% of patients who had a marginal resection. Nineteen percent of the patients in the marginal resection group died of their oral cancer, two of five patients with local recurrence. Ten percent of patients in the segmental resection group died of oral cancer; no local recurrences were seen.

CONCLUSION

There is no completely accurate method of diagnosing bony invasion of the mandible by oral squamous cell carcinoma. A combination of clinical examination, plain radiographs, and computed tomography (CT) scans may improve the diagnosis. Marginal resection is best reserved for cancers close to the bone with no invasion, minimal cortical invasion, or with early "arrosive" invasion. It is best in the symphysis region. Careful case selection will allow a favorable oncologic outcome with preservation of the mandibular contour.

Interleukin-10 as a possible mediator of immunosuppressive effect in patients with squamous cell carcinoma of the head and neck

BACKGROUND

Depressed cell-mediated immunity is a frequent event in patients with head and neck cancer and is characterized by impairment of T cell-proliferative responses and natural killer cell and lymphokine-activated killer cell activity. This immunosuppressive effect appears to be mediated by a serum-derived factor. Certain cytokines, including transforming growth factor-beta (TGF-beta) and interleukin (IL)-10 have been shown to induce similar immunosuppressive effects. The present study was designed to examine the putative role of these cytokines in cellular immune suppression induced by patient serum.

METHODS

Serum was collected from multiple patients with newly diagnosed or recurrent squamous cell carcinoma of the head and neck. The serum was heat inactivated for 30 min and frozen in aliquots. Peripheral blood lymphocytes were isolated from normal human blood. Lymphocytes were suspended in RPMI and 15% concentrations of control and patient serum and stimulated with 0.75 mg% phytohemagglutinin. In addition, neutralizing antibodies to TGF-beta and IL-10 were added to lymphocyte cultures. At 24 h, and IL-2 response assay was performed. Finally, the sera were examined for the presence of TGF-beta and IL-10 using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

In seven of seven experiments, incubating cells with a neutralizing antibody to TGF-beta failed to counteract the immune suppression and restore proliferative response to IL-2. Also, an ELISA of these sera failed to demonstrate the presence of TGF-beta. In contrast, four of five experiments performed with neutralizing antibody to IL-10 showed significant restoration of proliferation in the presence of this antibody. Also, ELISA showed elevated IL-10 levels in 65% of the patients' sera in comparison to controls.

CONCLUSION

We conclude that TGF-beta is not responsible for the immunosuppressive effects induced by head and neck patient sera. However, the suppressive effect is reversed by blocking the biologic action of IL-10. Further experiments are needed to define the role of IL-10 in inducing the immunosuppressive effect.

Increased recurrence and metastasis in patients whose primary head and neck squamous cell carcinomas secreted granulocyte-macrophage colony-stimulating factor and contained CD34+ natural suppressor cells

Human head and neck squamous cell carcinomas (HNSCC) that produce high levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) have been shown to contain CD34+ natural suppressor cells that inhibit the activity of intratumoral T-cells. The present study evaluated whether GM-CSF production and the presence of CD34+ cells within primary HNSCC would translate into increased recurrence, metastasis or cancer-related death during the 2 years following surgical excision. Freshly excised primary HNSCC of 20 patients that subsequently developed disease, and of 17 patients that remained with no evidence of disease were analyzed for production of GM-CSF and for CD34+ cell content. The cancers of patients that subsequently developed recurrences or metastatic disease produced almost 4-fold the levels of GM-CSF and had approximately 2.5-fold the number of CD34+ cells as did cancers of patients that remained disease-free. In a second method of analysis, the prognostic significance of high vs. low GM-CSF and CD34+ cell values was evaluated. These analyses showed that patients whose cancers produced high GM-CSF levels or had a high CD34+ cell content had a disproportionately high incidence of recurrence or metastatic disease (94% and 100%, respectively), while the majority of patients whose primary cancers produced low levels of GM-CSF or had a low CD34+ cell content remained disease-free (16% and 19%, respectively). Our results indicate that the presence of CD34+ cells in GM-CSF-producing HNSCC is associated with a poorer prognosis for the cancer patients and suggest the utility of these parameters as prognostic indicators of outcome. Mechanistically, our results suggest that the presence of immune suppressive CD34+ cells in GM-CSF-producing HNSCC leads to increased tumor recurrence or metastasis.

Mechanisms of immune suppression in patients with head and neck cancer: influence on the immune infiltrate of the cancer

Freshly excised human head and neck cancers (219 primary cancers; 64 metastatic lymph node cancers) were analyzed for the immune inhibitory mediators released from the cancer tissues and the immune infiltrate within the tumor. Significant levels of the immune inhibitory mediators transforming growth factor-beta (TGF-beta), prostaglandin E2 (PGE2) and interleukin-10 (IL-10) were released from these cancers. Also released was granulocyte-macrophage colony-stimulating factor (GM-CSF), whose secretion was associated with an intratumoral presence of CD34+ cells. We have previously shown that CD34+ cells within human head and neck cancers are immune inhibitory granulocyte-macrophage progenitor cells. The presence of TGF-beta, PGE2 and IL-10 was associated with a reduced content of CD8+ T-cells within the cancers. The CD4+ cell content appeared to be less affected by these immune inhibitory mediators. Instead, parameters indicative of CD4+ cell function (p55 IL-2 receptor expression, release of IL-2 and IFN-gamma) were diminished in cancers that released higher levels of TGF-beta, IL-10 and GM-CSF and had a higher CD34+ cell content. Furthermore, metastatic cancers released higher levels of the soluble immune inhibitory mediators and lower levels of IFN-gamma and IL-2 than did primary cancers, although CD34+ cells were similarly present in both primary and metastatic cancers. Our results show that human head and neck cancers have a multiplicity of non-mutually exclusive mechanisms of immune suppression that are most prominently associated with reduced CD8+ cell influx and reduced influx and altered function of intratumoral CD4+ cells.

Immune parameters of mice bearing human head and neck cancer

A xenogeneic human head and neck squamous cell carcinoma (HNSCC) model in immunocompetent mice was evaluated for its requirement of cyclosporine for progressive tumor growth. Tumor growth and T cell functions were assessed in mice receiving cyclosporine treatment for various lengths of time. Tumor cells were injected s.c. on day 1 and cyclosporine was injected i.p. daily on days 1, 1-7, 1-14, 1-21, or for the entire 28 days of tumor growth. All mice developed tumors. These tumors were confirmed to be squamous carcinomas of human origin histologically and by positive staining for human MHC class I antigen expression. Tumors were largest in mice that received cyclosporine for days 1-21 or days 1-28. Increased tumor size was associated with increased serum levels of tumor-reactive antibodies, an increased intratumoral frequency of CD4+ and CD8+ cells, but a diminished production of interleukin-2 (IL-2) by the tumor infiltrate. Also correlating with increasing tumor size was splenomegaly, a decline in the frequency, but not the absolute levels, of splenic CD4+ and CD8+ cells, and a diminished capacity to proliferate in response to concanavalin A and to be stimulated to secrete IL-2. The HNSCC tumors contributed to the immune decline since T cell functions were more depressed in the tumor bearers than in control mice receiving only cyclosporine treatment. These results demonstrate that human HNSCC tumor xenografts can grow in mice even with limited cyclosporine treatment, and that the survival of these xenografts may, in part, be due to a tumor-induced decline in select T cell functions.

Construction and characterization of the chimeric monoclonal antibody E48 for therapy of head and neck cancer

Data from an ongoing clinical radioimmunoscintigraphy trial indicate that 99mTc-labeled monoclonal antibody (mAb) E48 is highly capable of selectively targeting squamous cell carcinoma of the head and neck (HNSCC). The percentage of the injected dose per gram of tumor tissue was found to be high, rendering mAb E48 a promising candidate mAb for therapeutic purposes. We now describe the construction of a chimeric (mouse/human) mAb E48 by recombinant DNA technology. The genes encoding the variable domains of the heavy and light chain were cloned and ligated into expression vectors containing the human gamma 1 heavy-chain gene and the human kappa light-chain gene respectively. Biological properties of the resulting chimeric mAb E48 were compared to the murine form in vitro and in vivo. The reactivities of chimeric (c)mAb and murine (m)mAb E48 with HNSCC, as assessed by immunohistochemical staining as well as immuno-blotting were shown to be similar. The affinity constant appeared to be 0.9 x 10(10) M-1 and 1.6 x 10(10) M-1 for the mmAb and cmAb respectively. The biodistribution of both antibodies was tested by simultaneous injection into nude mice bearing human HNSCC xenografts. cmAb E48 was found to be cleared more rapidly from the blood than mmAb E48, resulting in a 30% lower tumor uptake but similar tumor to non-tumor ratios, 3 days after injection. Moreover, it was shown that cmAb E48 is highly capable of lysing HNSCC targets in ADCC assays in vitro, whereas the mmAb appeared to be almost inactive. These data indicate that cmAb E48 has potential as a targeting agent for the eradication of HNSCC in man.