The impact of T-cell immunity on ovarian cancer outcomes

Indoleamine 2,3-dioxygenase and immune tolerance in ovarian cancer

PURPOSE OF REVIEW

Ovarian cancer is the leading cause of cancer death among gynecologic malignancies despite significant advances in cytoreductive surgery and chemotherapy, and novel therapeutic approaches are urgently needed. Immunotherapy is one of these strategies; however, its clinical applications have shown limited efficacy. This may be attributed to tumor-induced immune tolerance, and much attention has been paid to overcoming these immune resistance mechanisms. This review focuses on the immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO) and shows the role of IDO and its clinical potential in ovarian cancer.

RECENT FINDINGS

IDO suppresses the proliferation of effector T cells or natural killer cells and their killer functions. In ovarian cancer, high IDO expression in tumor cells was correlated with a reduced number of tumor-infiltrating lymphocytes. The IDO expression was also correlated with advanced surgical stage and impaired survival. Preclinical studies in mice demonstrated that oral administration of IDO inhibitors suppressed peritoneal dissemination and potentiated the antitumor efficacy of chemotherapeutic agents.

SUMMARY

IDO induces immune tolerance and promotes ovarian cancer progression. Tumoral IDO expression is correlated with impaired clinical outcome. IDO inhibition may therefore be a promising strategy to restore host antitumor immunity and to enhance the antitumor potential of current chemotherapy or immunotherapy for advanced ovarian cancer.

Prognostic impact of lymphocytes in soft tissue sarcomas

Purpose

The purpose of this study was to clarify the prognostic significance of lymphocyte infiltration in soft tissue sarcomas (STS). Prognostic markers in potentially curable STS should guide therapy after surgical resection. The immune status at the time of resection may be important, but the prognostic significance of tumor infiltrating lymphocytes is controversial as the immune system has conflicting roles during cancer development.

Experimental Design

Tissue microarrays from 249 patients with STS were constructed from duplicate cores of viable and representative neoplastic tumor areas. Immunohistochemistry was used to evaluate the CD3+, CD4+, CD8+, CD20+ and CD45+ lymphocytes in tumors.

Results

In univariate analyses, increased numbers of CD4+ (P = 0.008) and CD20+ (P = 0.006) lymphocytes in tumor correlated significantly with an improved disease-specific survival (DSS) in patients with wide resection margins (n = 108). In patients with non-wide resection margins (n = 141) increased numbers of CD3+ (P = 0.028) lymphocytes in tumor correlated significantly with shorter DSS. In multivariate analyses, a high number of CD20+ lymphocytes (HR = 5.5, CI 95%  = 1.6–18.6, P = 0.006) in the tumor was an independent positive prognostic factor for DSS in patients with wide resections margins.

Conclusions

High density of CD20+ lymphocytes in STS with wide resection margins is an independent positive prognostic indicator for these patients. Further research is needed to define if CD20+ cells can modify tumors in a way that reduces disease progression and metastatic potential.

Polyfunctional T-cell responses are disrupted by the ovarian cancer ascites environment and only partially restored by clinically relevant cytokines

Background

Host T-cell responses are associated with favorable outcomes in epithelial ovarian cancer (EOC), but it remains unclear how best to promote these responses in patients. Toward this goal, we evaluated a panel of clinically relevant cytokines for the ability to enhance multiple T-cell effector functions (polyfunctionality) in the native tumor environment.

Methodology/Principal Findings

Experiments were performed with resident CD8+ and CD4+ T cells in bulk ascites cell preparations from high-grade serous EOC patients. T cells were stimulated with α-CD3 in the presence of 100% autologous ascites fluid with or without exogenous IL-2, IL-12, IL-18 or IL-21, alone or in combination. T-cell proliferation (Ki-67) and function (IFN-γ, TNF-α, IL-2, CCL4, and CD107a expression) were assessed by multi-parameter flow cytometry. In parallel, 27 cytokines were measured in culture supernatants. While ascites fluid had variable effects on CD8+ and CD4+ T-cell proliferation, it inhibited T-cell function in most patient samples, with CD107a, IFN-γ, and CCL4 showing the greatest inhibition. This was accompanied by reduced levels of IL-1β, IL-1ra, IL-9, IL-17, G-CSF, GM-CSF, Mip-1α, PDGF-bb, and bFGF in culture supernatants. T-cell proliferation was enhanced by exogenous IL-2, but other T-cell functions were largely unaffected by single cytokines. The combination of IL-2 with cytokines engaging complementary signaling pathways, in particular IL-12 and IL-18, enhanced expression of IFN-γ, TNF-α, and CCL4 in all patient samples by promoting polyfunctional T-cell responses. Despite this, other functional parameters generally remained inhibited.

Conclusions/Significance

The EOC ascites environment disrupts multiple T-cell functions, and exogenous cytokines engaging diverse signaling pathways only partially reverse these effects. Our results may explain the limited efficacy of cytokine therapies for EOC to date. Full restoration of T-cell function will require activation of signaling pathways beyond those engaged by IL-2, IL-12, IL-18, and IL-21.

Urinary neopterin does not reflect the local antitumor immune milieu in ovarian cancer

The main objective of the present investigation was to study the urinary neopterin excretion in the context of the activation of the adaptive cellular immune system at the tumor site. For this purpose, we compared pre-treatment urinary neopterin levels measured in 92 ovarian cancer patients, with intratumoral levels of mRNA transcripts from factors either involved in the adaptive antitumor immune defense (CD3, IFN-γ, IRF-1, IRF-2, SOCS1 and iNOS) or immune tolerance (FoxP3). This study did not reveal an association between urinary neopterin and one of these investigated "on tumor site transcripts". From all the factors reflecting the magnitude of the local adaptive antitumor response, intratumoral IRF-1 expression above the edge of the 25th percentile was found to predict most reliably favorable progression-free (median 34 months vs. 10 months; p < 0.001) and overall (median 52 months vs. 16 months; p < 0.001) survival. In contrast, pre-treatment urinary neopterin excretion above 275 μmol/mol creatinine, which indicates an unspecific activation of the innate immune system, was associated with a very poor overall survival with a median of only 11 months when compared with a median overall survival of 40 months in patients with lower urinary neopterin excretion (p = 0.021). Interestingly, the considerable survival benefit in patients with high IRF-1-expressing cancers was completely abrogated as well for progression-free as for overall survival when urinary neopterin concentrations were found to be concomitantly elevated. These findings demonstrate that in ovarian carcinomas the unspecific "cancer-related inflammation" contributes to a significant subversion of the adaptive antitumor immune defense mounted at the tumor site.

Allogeneic hematopoietic stem cell transplantation in ovarian cancer-the EBMT experience

Although preliminary results suggest that allogeneic hematopoietic stem cell transplantation (allo HCT) for ovarian cancer (OC) is a feasible procedure, the low patient number in previous studies had limited ability to evaluate the true benefit of allo HCT in OC. This retrospective multicenter study included 30 patients with OC allografted between 1995 and 2005 to determine the outcome of patients with OC treated with allo HCT. Prior to allo HCT, patients were in complete response (n = 1), partial response (n = 7), stable disease (n = 11) or had progressive disease (n = 13). An objective response (OR) was observed in 50% (95% CI, 33-67) of patients. Three patients of responding patients had an objective response following the development of acute graft-versus-host disease (aGvHD). The cumulative incidence of chronic GvHD (cGVHD) was 34% (95% CI, 18-50). Transplant relative mortality rates were 7 and 20% on day 100 and 1 year, respectively. With a median follow-up of 74.5 months (range 16-148), median progression free survival (PFS) was 6 months and median overall survival (OS) was 10.4 months. Patients who developed cGvHD following allo HCT had a significant OS improvement compared to those who did not (17.6 months vs. 6.5 months, p = 0.042). However, PFS was not similarly significantly improved in patients who developed cGvHD (12 months versus 3.7 months, p = 0.81). Allo HCT in OC may lead to graft-versus-OC effects. Their clinical relevance remains to be shown.

Successful eradication of established peritoneal ovarian tumors in SCID-Beige mice following adoptive transfer of T cells genetically targeted to the MUC16 antigen

PURPOSE

Most patients diagnosed with ovarian cancer will ultimately die from their disease. For this reason, novel approaches to the treatment of this malignancy are needed. Adoptive transfer of a patient's own T cells, genetically modified ex vivo through the introduction of a gene encoding a chimeric antigen receptor (CAR) targeted to a tumor-associated antigen, is a novel approach to the treatment of ovarian cancer.

EXPERIMENTAL DESIGN

We have generated several CARs targeted to the retained extracellular domain of MUC16, termed MUC-CD, an antigen expressed on most ovarian carcinomas. We investigate the in vitro biology of human T cells retrovirally transduced to express these CARs by coculture assays on artificial antigen-presenting cells as well as by cytotoxicity and cytokine release assays using the human MUC-CD(+) ovarian tumor cell lines and primary patient tumor cells. Further, we assess the in vivo antitumor efficacy of MUC-CD-targeted T cells in SCID-Beige mice bearing peritoneal human MUC-CD(+) tumor cell lines.

RESULTS

CAR-modified, MUC-CD-targeted T cells exhibited efficient MUC-CD-specific cytolytic activity against both human ovarian cell and primary ovarian carcinoma cells in vitro. Furthermore, expanded MUC-CD-targeted T cells infused through either i.p. injection or i.v. infusion into SCID-Beige mice bearing orthotopic human MUC-CD(+) ovarian carcinoma tumors either delayed progression or fully eradicated disease.

CONCLUSION

These promising preclinical studies justify further investigation of MUC-CD-targeted T cells as a potential therapeutic approach for patients with high-risk MUC16(+) ovarian carcinomas.

Predictive and prognostic protein biomarkers in epithelial ovarian cancer: recommendation for future studies

Epithelial ovarian cancer is the most lethal gynecological malignancy. Due to its lack of symptoms, this disease is diagnosed at an advanced stage when the cancer has already spread to secondary sites. While initial rates of response to first treatment is >80%, the overall survival rate of patients is extremely low, mainly due to development of drug resistance. To date, there are no reliable clinical factors that can properly stratify patients for suitable chemotherapy strategies. Clinical parameters such as disease stage, tumor grade and residual disease, although helpful in the management of patients after their initial surgery to establish the first line of treatment, are not efficient enough. Accordingly, reliable markers that are independent and complementary to clinical parameters are needed for a better management of these patients. For several years, efforts to identify prognostic factors have focused on molecular markers, with a large number having been investigated. This review aims to present a summary of the recent advances in the identification of molecular biomarkers in ovarian cancer patient tissues, as well as an overview of the need and importance of molecular markers for personalized medicine in ovarian cancer.

Targeting CCL11 in the treatment of ovarian cancer

IMPORTANCE OF THE FIELD

The chemokine network, comprised of mediators of inflammation, has been implicated in the development of a number of human cancers. The eosinophil chemoattractant CCL11 was recently shown to play a role in the development of ovarian cancer. Here we review findings regarding CCL11 and discuss its use as a target in the treatment of ovarian cancer.

AREAS COVERED IN THIS REVIEW

We review published findings related to the physiological actions of CCL11, its tumourigenic effects, the chemokine network and inflammatory response present in ovarian cancer, and the current state of therapeutics targeting CCL11 and its receptors. Findings published within the last 10 years receive particular attention.

WHAT THE READER WILL GAIN

An overview of the emerging role of the chemokine network in malignancy and a review of the role of CCL11 in ovarian tumourigenesis. The reader will be presented with a description of the unique aspects of CCL11 action and the inflammatory environment in the setting of ovarian malignancy that make this chemokine an attractive target for intervention.

TAKE HOME MESSAGE

Targeting CCL11 and its receptors through the use of monoclonal antibodies and small-molecule inhibitors may represent a beneficial new avenue of ovarian cancer treatment.

Tumor infiltrating lymphocytes but not serum pituitary antibodies are associated with poor clinical outcome after surgery in patients with pituitary adenoma

CONTEXT

Serum pituitary antibodies (Pit Abs) and tumor-infiltrating lymphocytes (TILs) have been described in pituitary adenomas, but their clinical significance remains unknown.

OBJECTIVE

The objective of the study was to assess Pit Abs and TILs prevalence in pituitary adenomas and their influence on clinical outcome.

DESIGN

This was a prevalence case-control study.

PATIENTS AND SETTING

Two hundred ninety-one pituitary adenoma cases (110 non-secreting, 30 ACTH-69 GH-71 prolactin- and 13 TSH-secreting adenoma; 177 operated and 114 untreated), 409 healthy controls, and 14 autoimmune hypophysitis were enrolled in a tertiary referral center.

INTERVENTION

Pit Abs were measured using immunofluorescence in all cases and controls (n = 714). The presence of TILs was evaluated using CD45 staining in a subset of adenomas surgically treated (n = 72).

MAIN OUTCOME MEASURE

Clinical response of pituitary adenoma after surgery was evaluated.

RESULTS

Pit Abs prevalence was higher in adenomas (5.1%) than healthy subjects (0.7%, P < 0.0001) and lower than in autoimmune hypophysitis patients (57%, P < 0.0001). Similarly, TILs prevalence was higher in adenomas than normal pituitary (P = 0.01) and lower than in autoimmune hypophysitis (P < 0.0001). No correlation between Pit Abs and TILs was found (P = 0.78). A poor clinical outcome was more common in adenoma patients with TILs (11 of 18, 61%) than in those without (17 of 54, 31%, P = 0.026). Multivariate regression analysis identified the presence of TILs as independent prognostic factor for persistence/recurrence of pituitary adenoma.

CONCLUSIONS

TILs and Pit Abs are present in a significant number of pituitary adenoma patients. Cell-mediated immunity appears to be predictive of a less favorable clinical outcome.

T cell density and location can influence the prognosis of ovarian cancer

The aims of this study were to examine the significance of CD3+ cells in patients with epithelial ovarian cancer and to determine their influence on the disease in relation to their location within tumours. A 157-core tissue-microarray constructed from primary ovarian cancer patients treated at Nottingham-University-Hospitals (2000-2007) was stained for the T-cell marker CD3. The number of CD3+ cells in direct contact with tumour cells was counted per tumour area. These were considered as "intra-tumoural T-cells (ITTC)". Cores were divided into CD3 'high' or 'low' density tumours. "Stromal T-cells (STC)" were assigned as 'positive' or 'negative'. The study population had a median follow-up time of 36-months (0-75). The number of ITTC counted in tumour cores ranged between 0 and 184/mm(2). 90-tumours-(57%) were found to be in the "low-density" rubric, while 56-(36%) were of a "high-density" T-cell population. STC were found in 118-cores-(75%)-compared to 22-cores-(14%)-negative cores. Higher number of ITTC correlated with lower-grade-(p = 0.045), tumour-type-(p = 0.034), and longer-median-survival-times (57-versus 37-months for high-and low-ITTC densities, respectively, p = 0.038). This relationship was reversed when tumours were infiltrated by CD3+ cells in the stroma, predicting worse-survival (Log-rank-test, p = 0.028). Combining ITTC with STC produced an interesting pattern where the ITTC-low/STC + ve had the worst prognosis (p = 0.003). Infiltration of ovarian cancer by T-cells can influence its prognosis depending on the location of these cells (intra-tumoural-versus-stromal). The former predicts improved survival, while the latter is probably contributing to tumour progression and, in turn, worse survival.

Ovarian cancer tumor infiltrating T-regulatory (T(reg)) cells are associated with a metastatic phenotype

OBJECTIVE

The objective of this study was to examine the clinicopathologic correlates of T-regulatory (T(reg)) cell infiltration in serous ovarian cancers and to define gene signatures associated with high T(reg)s.

METHODS

Tumor infiltrating T(reg) and cytotoxic T-cells (CTLs) were quantitated in 232 primary serous ovarian cancers by immunostaining for FOXP3 and CD8. Expression microarray analysis was performed in a subset of 48 advanced cancers with the highest and lowest numbers of infiltrating T(reg)s and a genomic signature was developed using binary regression. ANOVA analysis was performed to assess the most differentially expressed genes and these genes were further assessed using Ingenuity Pathway Analysis (IPA) software.

RESULTS

High T(reg) infiltration in ovarian cancers was associated with high grade (p<0.0001), advanced stage (p=0.004) and suboptimal debulking (p<0.04), but not with survival. In contrast, high tumor infiltrating CD8 CTL infiltration was associated with favorable survival (median survival 48.7 vs. 34.6 months, p=0.01). A microarray-based genomic signature for high tumor-infiltrating T(reg) cells had a 77% predictive accuracy using leave-one-out cross-validation. ANOVA of microarray data revealed the antigen presentation pathway as the most differentially expressed canonical pathway (p<0.00001) between cancers with high and low T(reg) cells.

CONCLUSIONS

These data suggest that there may be an association between increased T(reg) cell infiltration in ovarian cancers and advanced stage. Increased T(reg) infiltration is characterized by a genomic signature enriched with several immunologic pathway genes. Therapeutic strategies that reduce tumor infiltrating T(reg) cells are under investigation and may prove useful in ovarian cancers with high numbers of these cells.

Clinicopathological characteristics of tumor-infiltrating lymphocytes in colorectal cancer

AIM: To investigate the clinicopathological characteristics and immunohistochemical features of tumor-infiltrating lymphocyte (TIL) in colorectal cancer, and analyze the correlations between the presence of massive TIL and various pathological parameters in colorectal cancer.

METHODS: The histopathological features of tumor-infiltrating lymphocytes in 370 cases of colorectal cancer were detected by light microscopy and immunohistochemistry. The correlations between the presence of massive TIL and various clinicopathological parameters in colorectal cancer were then analyzed.

RESULTS: Of 370 cases of colorectal cancer detected, 303 (81.9%) showed mild infiltration of scattered lymphocytes, and 67 (18.1%) showed massive lymphocyte infiltration. The majority of lymphocytes were infiltrated into both the stromal and epithelial components of carcinoma. TIL were often distributed around cancer tissue, and separated cancer tissue from normal tissue. Immunohistochemical staining showed that TIL were mainly composed of CD3+ T cells, CD20⁺ CD79α+ B cells, and CD56+ natural killer cells. T-cell-restricted intracellular antigen-1 (TIA-1) was strongly expressed in TIL. Massive lymphocyte infiltration was correlated with tumor differentiation, invasive depth and lymph node metastasis in colorectal cancer (χ² = 4.954, 11.240, 12.768; P = 0.026, 0.001, 0.000, respectively).

CONCLUSION: The clinicopathological characteristics of tumor-infiltrating lymphocytes in colorectal cancer vary significantly. The presence of massive tumor-infiltrating lymphocytes is a positive prognostic factor for colorectal cancer.

Chimeric NKG2D expressing T cells eliminate immunosuppression and activate immunity within the ovarian tumor microenvironment

Adoptive transfer of T cells expressing chimeric NKG2D (chNKG2D) receptors, a fusion of NKG2D and CD3zeta, can lead to long-term, tumor-free survival in a murine model of ovarian cancer. To determine the mechanisms of chNKG2D T cell antitumor efficacy, we analyzed how chNKG2D T cells altered the tumor microenvironment, including the tumor-infiltrating leukocyte populations. chNKG2D T cell treatment of mice bearing ID8 tumor cells increased the number and activation of NK cells and increased the activation of host CD8+ T cells within the tumor. Foxp3+ regulatory T cells at the tumor site decreased more than 300-fold after chNKG2D T cell treatment. Tumor-associated regulatory T cells expressed cell surface NKG2D ligands and were killed by chNKG2D T cells in a perforin-dependent manner. chNKG2D T cells also altered the function of myeloid cells at the tumor site, changing these cells from being immunosuppressive to enhancing T cell responses. Cells isolated from the tumor produced elevated amounts of IFN-gamma, NO, and other proinflammatory cytokines after chNKG2D T cell treatment. ChNKG2D T cells required perforin, IFN-gamma, and GM-CSF to induce a full response at the tumor site. In addition, transfer of chNKG2D T cells into mice bearing tumors that were established for 5 weeks led to long-term survival of the mice. Thus, chNKG2D T cells altered the ovarian tumor microenvironment to eliminate immunosuppressive cells and induce infiltration and activation of antitumor immune cells and production of inflammatory cytokines. This induction of an immune response likely contributes to chNKG2D T cells' ability to eliminate established tumors.

Density of tumour stroma is correlated to outcome after adoptive transfer of CD4+ and CD8+ T cells in a murine mammary carcinoma model

Adoptive immunotherapy shows promise for the treatment of cancer; however, partial or mixed responses remain common outcomes due to the heterogeneity of tumours. We studied three murine mammary tumour lines that express an ovalbumin-tagged version of HER-2/neu and reproducibly undergo complete regression (CR), partial regression (PR), or progressive disease (PD) after adoptive transfer of ovalbumin-specific CD8(+) (OT-I) and CD4(+) (OT-II) T cells. The three tumour lines were implanted in immunocompetent C57Bl/6 host mice, and established tumours were treated by adoptive transfer of naive OT-I and OT-II T cells. Tumours of the CR and PR classes triggered almost indistinguishable T cell responses in terms of activation, proliferation, trafficking to the tumour site, infiltration of tumour stroma, and intratumoural T cell proliferation; however, tumours of the PR class showed reduced infiltration of tumour epithelium by donor T cells. PD responses were associated with early impairment of T cell activation and proliferation in draining lymph node, followed by negligible infiltration of tumour tissue by donor T cells. Histopathological determinants of outcome were investigated through an unsupervised analysis of 64 untreated tumours representing the three response classes. Tumours of the CR class had proportionately more stroma, which had a looser, more collagen-rich histological appearance. Thus, the amount and composition of tumour stroma distinguished successfully (CR) from unsuccessful (PR or PD) outcomes after adoptive T cell transfer, a finding that might facilitate the design of immunotherapy trials for human breast cancer.

Systematic analysis of immune infiltrates in high-grade serous ovarian cancer reveals CD20, FoxP3 and TIA-1 as positive prognostic factors

Background

Tumor-infiltrating T cells are associated with survival in epithelial ovarian cancer (EOC), but their functional status is poorly understood, especially relative to the different risk categories and histological subtypes of EOC.

Methodology/Principal Findings

Tissue microarrays containing high-grade serous, endometrioid, mucinous and clear cell tumors were analyzed immunohistochemically for the presence of lymphocytes, dendritic cells, neutrophils, macrophages, MHC class I and II, and various markers of activation and inflammation. In high-grade serous tumors from optimally debulked patients, positive associations were seen between intraepithelial cells expressing CD3, CD4, CD8, CD45RO, CD25, TIA-1, Granzyme B, FoxP3, CD20, and CD68, as well as expression of MHC class I and II by tumor cells. Disease-specific survival was positively associated with the markers CD8, CD3, FoxP3, TIA-1, CD20, MHC class I and class II. In other histological subtypes, immune infiltrates were less prevalent, and the only markers associated with survival were MHC class II (positive association in endometrioid cases) and myeloperoxidase (negative association in clear cell cases).

Conclusions/Significance

Host immune responses to EOC vary widely according to histological subtype and the extent of residual disease. TIA-1, FoxP3 and CD20 emerge as new positive prognostic factors in high-grade serous EOC from optimally debulked patients.

p53 autoantibodies, cytokine levels and ovarian carcinogenesis

OBJECTIVE

To address the hypothesis that type II ovarian carcinoma, mutation of p53 and plasma levels of particular cytokines are associated with the generation of p53-specific serum autoantibody (AAb) responses in patients.

METHODS

Levels of CA125, 17 cytokines and AAbs to tumor-associated antigens including p53 were measured in plasma of 130 gynecologic tumor patients and 84 healthy controls. TP53 exons 4-9 were sequenced in tumor specimens.

RESULTS

p53 AAbs are associated with high grade, but not low grade ovarian carcinoma. Seropositivity for p53 AAb occurred only in those ovarian carcinoma patients whose tumors contained mutated TP53, regardless of the exon targeted. Higher p53 AAb levels were detected in ovarian carcinoma patients who had higher stage disease, but p53 AAb levels were not correlated with CA125 levels. Among high-grade carcinoma patients, there was no relationship between p53 AAb seropositivity and seropositivity to other tumor-associated antigens tested, CA125 level or survival outcome. Both high and low grade ovarian carcinoma patients exhibited elevated levels of IL6, IL8 and IL10 as compared to healthy volunteers, although increased levels of IL5, MCP1, MIP1 and TNFalpha were associated only with high grade and advanced disease. Higher levels of p53AAb responses were correlated with elevated circulating IL4 and IL12, but reduced IL8 levels.

CONCLUSION

Type II, but not type I, ovarian carcinoma patients had elevated serum levels of p53 AAb. P53 AAb is associated with mutation of TP53, higher plasma IL4 and IL12 but lower plasma IL8 levels and no survival advantage.

Evidence of systemic Th2-driven chronic inflammation in patients with metastatic melanoma

PURPOSE

Immunotherapeutic modalities are commonly used for treatment of patients with melanoma. The therapeutic success in preclinical models has not yielded the expected clinical results. To understand this discrepancy, we attempted to define immune homeostasis of 209 patients with melanoma across stages of disease relative to normal controls.

EXPERIMENTAL DESIGN

Peripheral blood mononuclear cells (PBMC) and plasma were collected from patients and healthy donors. PBMC were analyzed for frequencies of natural killer, dendritic, and T cells and their functional status. Matched plasma samples were analyzed for the concentrations of 27 cytokines, chemokines, and growth factors. RNA was isolated from 24 metastatic melanoma tumor biopsies and profiled by microarray analysis.

RESULTS

The frequency of natural killer, T, and dendritic cells in patients does not significantly change across stages of melanoma. However, plasma concentrations of Th2 cytokines [interleukin (IL)-4, IL-5, IL-10, and IL-13] in tumor-bearing patients were significantly higher than those with resected melanoma. Expression array analysis of metastatic melanoma revealed that the malignant melanocytes were not the source of the Th2 cytokines but did highly up-regulate vascular endothelial growth factor (VEGF) transcripts, consistent with plasma VEGF concentrations. In vitro VEGF exposure of normal PBMC lead to repolarization from Th1 to Th2 emulating the state of metastatic melanoma.

CONCLUSIONS

Patients with metastatic melanoma exist in a state of Th2-mediated "chronic inflammation" as a result of at least VEGF overproduction by malignant tumors. These data support prior observations regarding the effect of VEGF on immune cell function and suggests consideration of VEGF inhibitors in future cancer immunotherapy clinical studies in metastatic melanoma.

Tumor-infiltrating T cells correlate with NY-ESO-1-specific autoantibodies in ovarian cancer

Background

Tumor-infiltrating CD8+ T cells are correlated with prolonged progression-free and overall survival in epithelial ovarian cancer (EOC). A significant fraction of EOC patients mount autoantibody responses to various tumor antigens, however the relationship between autoantibodies and tumor-infiltrating T cells has not been investigated in EOC or any other human cancer. We hypothesized that autoantibody and T cell responses may be correlated in EOC and directed toward the same antigens.

Methodology and Principal Findings

We obtained matched serum and tumor tissue from 35 patients with high-grade serous ovarian cancer. Serum samples were assessed by ELISA for autoantibodies to the common tumor antigen NY-ESO-1. Tumor tissue was examined by immunohistochemistry for expression of NY-ESO-1, various T cell markers (CD3, CD4, CD8, CD25, FoxP3, TIA-1 and Granzyme B) and other immunological markers (CD20, MHC class I and MHC class II). Lymphocytic infiltrates varied widely among tumors and included cells positive for CD3, CD8, TIA-1, CD25, FoxP3 and CD4. Twenty-six percent (9/35) of patients demonstrated serum IgG autoantibodies to NY-ESO-1, which were positively correlated with expression of NY-ESO-1 antigen by tumor cells (r = 0.57, p = 0.0004). Autoantibodies to NY-ESO-1 were associated with increased tumor-infiltrating CD8+, CD4+ and FoxP3+ cells. In an individual HLA-A2+ patient with autoantibodies to NY-ESO-1, CD8+ T cells isolated from solid tumor and ascites were reactive to NY-ESO-1 by IFN-γ ELISPOT and MHC class I pentamer staining.

Conclusion and Significance

We demonstrate that tumor-specific autoantibodies and tumor-infiltrating T cells are correlated in human cancer and can be directed against the same target antigen. This implies that autoantibodies may collaborate with tumor-infiltrating T cells to influence clinical outcomes in EOC. Furthermore, serological screening methods may prove useful for identifying clinically relevant T cell antigens for immunotherapy.