Resistance to apoptosis and expansion of regulatory T cells in relation to the detection of circulating tumor cells in patients with metastatic epithelial cancer. J Clin Immunol. 2008;28:107-114. [PMID: 17939021 DOI: 10.1007/s10875-007-9139-2]

A Pilot Randomized Trial Assessing the Effect of a Psychoeducational Intervention on Psychoneuroimmunological Parameters Among Patients With Nonmetastatic Breast Cancer

OBJECTIVE

The aim of this study was to determine a potential benefit of the specific psychoeducational intervention "Learning to Live with Cancer" (LTLWC) for patients with operated nonmetastatic breast cancer, with respect to psychological variables and endocrine and immune parameters.

METHODS

Fifty-two postmenopausal women with operated stage I to III breast cancer were randomized to either a breast cancer intervention group (BCIG, n = 30) who immediately began participating in the LTLWC intervention program or to a breast cancer control group (BCCG, n = 22). Matched healthy women were asked to participate as a noncancer comparison group (n = 26). All participants were evaluated at three different time points (t1-t3) using a set of standardized questionnaires and blood samples were taken to analyze immune cell subsets and stress hormone levels.

RESULTS

A significant reduction in trait anxiety/State Trait Anxiety Inventory score was observed in the BCIG (t1: median = 35.0 [interquartile range = 28.0-38.0] versus t3: median = 26.0 [interquartile range = 18.5-37.0], p = .0001) compared with the BCCG (t1: median = 41.0 [interquartile range =32.75-49.0]; t3: median = 38.5 [interquartile range = 30.75-46.5], p = .01524; p interaction = .001). In parallel, a significant rise of serotonin levels (t1: median = 66.5 ng/ml [interquartile range = 11.50-106.00] versus t3: median = 80.5 ng/ml [interquartile range =59.00-118.00], p = .00008) as well as a significant reduction of the elevated number of Treg cells at baseline (t1: median = 4.45% [interquartile range = 4.00-5.33] versus t3: median = 2.80% [interquartile range = 2.68-3.13], p < .00001) were observed in the BCIG versus no change in the BCCG. A significant statistical association between reduced trait anxiety and decreased Treg cell number could be demonstrated in the BCIG (r = .62, p < .01).

CONCLUSIONS

The observed results of this study provide preliminary support for the efficacy of the LTLWC program in significantly improving psychoneuroimmunological parameters in patients with nonmetastatic breast cancer.

The Interplay between Circulating Tumor Cells and the Immune System: From Immune Escape to Cancer Immunotherapy

Circulating tumor cells (CTCs) have aroused increasing interest not only in mechanistic studies of metastasis, but also for translational applications, such as patient monitoring, treatment choice, and treatment change due to tumor resistance. In this review, we will assess the state of the art about the study of the interactions between CTCs and the immune system. We intend to analyze the impact that the cells of the immune system have in limiting or promoting the metastatic capability of CTCs. To this purpose, we will examine studies that correlate CTCs, immune cells, and patient prognosis, and we will also discuss relevant animal models that have contributed to the understanding of the mechanisms of immune-mediated metastasis. We will then consider some studies in which CTCs seem to play a promising role in monitoring cancer patients during immunotherapy regimens. We believe that, from an accurate and profound knowledge of the interactions between CTCs and the immune system, new immunotherapeutic strategies against cancer might emerge in the future.

Clinical significance of circulating immune cells in left- and right-sided colon cancer

Background

Left-sided and right-sided colon cancers (LCCs and RCCs, respectively) differ in their epidemiology, pathogenesis, genetic and epigenetic alterations, molecular pathways and prognosis. Notably, immune response gene expression profiles have been shown to differ between patients with LCC and patients with RCC. The immune system plays an important role in tumor immunosurveillance, and there is increasing evidence that peripheral blood immune cells have a profound influence on tumor prognosis. This study aimed to determine the clinical significance of circulating immune cells with respect to colon tumor locations.

Methods

Different types of circulating immune cells were separated and analysed based on their surface markers by flow cytometry. We compared the numbers of dendritic cells (DCs) and T cell subsets in the peripheral blood of 94 patients with RCC or LCC and analysed the proportions of these immune cells in relation to tumor stage, tumor differentiation and lymphatic metastasis.

Results

We show that at later tumor stages, patients with LCC had higher levels of circulating myeloid DCs (P = 0.049) and plasmacytoid DCs (P = 0.018) than patients with RCC. In poorly differentiated tumors, LCC patients had significantly higher amount of plasmacytoid DCs (P = 0.036), CD4⁺ memory T (Tm) cells (P = 0.012), CD4⁺ T cells (P = 0.028), Tm cells (P = 0.014), and regulatory T cells (P = 0.001) than RCC patients. The levels of circulating CD4⁺ T cells, Tm cells and CD4⁺ Tm cells were significantly elevated at later stages in patients with LCC or RCC, while these cells decreased in poorly differentiated tumors in patients with RCC. Moreover, CD4⁺ Tm cell and CD4⁺ T cell levels are significantly associated with lymph node metastasis in patients with LCC and RCC.

Discussion

Circulating immune cells were associated with tumor location, tumor stage and tumor differentiation, and can be used to predict lymphatic metastasis in patients with colon cancer. This variation in systemic immunity could contribute to the differential prognosis of patients with colon cancer.

Circulating and disseminated tumour cells - mechanisms of immune surveillance and escape

Metastatic spread of tumour cells is the main cause of cancer-related deaths. Understanding the mechanisms of tumour-cell dissemination has, therefore, become an important focus for cancer research. In patients with cancer, disseminated cancer cells are often detectable in the peripheral blood as circulating tumour cells (CTCs) and in the bone marrow or lymph nodes as disseminated tumour cells (DTCs). The identification and characterization of CTCs and DTCs has yielded important insights into the mechanisms of metastasis, resulting in a better understanding of the molecular alterations and profiles underlying drug resistance. Given the expanding role of immunotherapies in the treatment of cancer, interactions between tumour cells and immune cells are the subject of intense research. Theoretically, cancer cells that exit the primary tumour site - leaving the protection of the typically immunosuppressive tumour microenvironment - will be more vulnerable to attack by immune effector cells; thus, the survival of tumour cells after dissemination might be the 'Achilles' heel' of metastatic progression. In this Review, we discuss findings relating to the interactions of CTCs and DTCs with the immune system, in the context of cancer immuno-editing, evasion from immune surveillance, and formation of metastases.

Impaired thymic export and increased apoptosis account for regulatory T cell defects in patients with non-ST segment elevation acute coronary syndrome

Regulatory T (Treg) cells play a protective role against the development of atherosclerosis. Previous studies have revealed Treg cell defects in patients with non-ST elevation acute coronary syndrome (NSTACS), but the mechanisms underlying these defects remain unclear. In this study, we found that the numbers of peripheral blood CD4(+)CD25(+)CD127(low) Treg cells and CD4(+)CD25(+)CD127(low)CD45RA(+)CD45RO(-) naive Treg cells were lower in the NSTACS patients than in the chronic stable angina (CSA) and the chest pain syndrome (CPS) patients. However, the number of CD4(+)CD25(+)CD127(low)CD45RA(-)CD45RO(+) memory Treg cells was comparable in all of the groups. The frequency of CD4(+)CD25(+)CD127(low)CD45RO(-)CD45RA(+)CD31(+) recent thymic emigrant Treg cells and the T cell receptor excision circle content of purified Treg cells were lower in the NSTACS patients than in the CSA patients and the CPS controls. The spontaneous apoptosis of Treg cells (defined as CD4(+)CD25(+)CD127(low)annexin V(+)7-AAD(-)) was increased in the NSTACS patients compared with the CSA and CPS groups. Furthermore, oxidized LDL could induce Treg cell apoptosis, and the oxidized LDL levels were significantly higher in the NSTACS patients than in the CSA and CPS groups. In accordance with the altered Treg cell levels, the concentration of TNF-α was increased in the NSTACS patients, resulting in a decreased IL-10/TNF-α ratio. These findings indicate that the impaired thymic output of Treg cells and their enhanced susceptibility to apoptosis in the periphery were responsible for Treg cell defects observed in the NSTACS patients.

A different immunologic profile characterizes patients with HER-2-overexpressing and HER-2-negative locally advanced breast cancer: implications for immune-based therapies

Introduction

The clinical efficacy of trastuzumab and taxanes is at least partly related to their ability to mediate or promote antitumor immune responses. On these grounds, a careful analysis of basal immune profile may be capital to dissect the heterogeneity of clinical responses to these drugs in patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy.

Methods

Blood samples were collected from 61 locally advanced breast cancers (36 HER2^- and 25 HER2⁺) at diagnosis and from 23 healthy women. Immunophenotypic profiling of circulating and intratumor immune cells, including regulatory T (Treg) cells, was assessed by flow cytometry and immunohistochemistry, respectively. Serum levels of 10 different cytokines were assessed by multiplex immunoassays. CD8⁺ T cell responses to multiple tumor-associated antigens (TAA) were evaluated by IFN-γ-enzyme-linked immunosorbent spot (ELISPOT). The Student's t test for two tailed distributions and the Wilcoxon two-sample test were used for the statistical analysis of the data.

Results

The proportion of circulating immune effectors was similar in HER2⁺ patients and healthy donors, whereas higher percentages of natural killer and Treg cells and a lower CD4⁺/CD8⁺ T cell ratio (with a prevalence of naïve and central memory CD8⁺ T cells) were observed in HER2^- cases. Higher numbers of circulating CD8⁺ T cells specific for several HLA-A*0201-restricted TAA-derived peptides were observed in HER2⁺ cases, together with a higher prevalence of intratumor CD8⁺ T cells. Serum cytokine profile of HER2⁺ patients was similar to that of controls, whereas HER2^- cases showed significantly lower cytokine amounts compared to healthy women (IL-2, IL-8, IL-6) and HER2⁺ cases (IL-2, IL-1β, IL-8, IL-6, IL-10).

Conclusions

Compared to HER2- cases, patients with HER2-overexpressing locally advanced breast cancer show a more limited tumor-related immune suppression. This may account for the clinical benefit achieved in this subset of patients with the use of drugs acting through, but also promoting, immune-mediated effects.

Immunological milieu in the peritoneal cavity at laparotomy for gastric cancer

AIM: To investigate the immunological repertoire in the peritoneal cavity of gastric cancer patients.

METHODS: The peritoneal cavity is a compartment in which immunological host-tumor interactions can occur. However, the role of lymphocytes in the peritoneal cavity of gastric cancer patients is unclear. We observed 64 patients who underwent gastrectomy for gastric cancer and 11 patients who underwent laparoscopic cholecystectomy for gallstones and acted as controls. Lymphocytes isolated from both peripheral blood and peritoneal lavage were analyzed for surface markers of lymphocytes and their cytokine production by flow cytometry. CD4⁺CD25^high T cells isolated from the patient’s peripheral blood were co-cultivated for 4 d with the intra-peritoneal lymphocytes, and a cytokine assay was performed.

RESULTS: At gastrectomy, CCR7^- CD45RA^- CD8⁺ effector memory T cells were observed in the peritoneal cavity. The frequency of CD4⁺ CD25 ^high T cells in both the peripheral blood and peritoneal cavity was elevated in patients at advanced stage [control vs stage IV in the peripheral blood: 6.89 (3.39-10.4) vs 15.34 (11.37-19.31), P < 0.05, control vs stage IV in the peritoneal cavity: 8.65 (5.28-12.0) vs 19.56 (14.81-24.32), P < 0.05]. On the other hand, the suppression was restored with CD4⁺ CD25^high T cells from their own peripheral blood. This study is the first to analyze lymphocyte and cytokine production in the peritoneal cavity in patients with gastric cancer. Immune regulation at advanced stage is reversible at the point of gastrectomy.

CONCLUSION: The immunological milieu in the peritoneal cavity of patients with advanced gastric cancer elicited a Th2 response even at gastrectomy, but this response was reversible.

Impaired thymic export and apoptosis contribute to regulatory T-cell defects in patients with chronic heart failure

OBJECTIVE

Animal studies suggest that regulatory T (T(reg)) cells play a beneficial role in ventricular remodeling and our previous data have demonstrated defects of T(reg) cells in patients with chronic heart failure (CHF). However, the mechanisms behind T(reg-)cell defects remained unknown. We here sought to elucidate the mechanism of T(reg-)cell defects in CHF patients.

METHODS AND RESULTS

We performed flow cytometry analysis and demonstrated reduced numbers of peripheral blood CD4(+)CD25(+)FOXP3(+)CD45RO(-)CD45RA(+) naïve T(reg) (nT(reg)) cells and CD4(+)CD25(+)FOXP3(+)CD45RO(+)CD45RA(-) memory T(reg) (mT(reg)) cells in CHF patients as compared with non-CHF controls. Moreover, the nT(reg)/mT(reg) ratio (p<0.01), CD4(+)CD25(+)FOXP3(+)CD45RO(-) CD45RA(+)CD31(+) recent thymic emigrant T(reg) cell (RTE-T(reg)) frequency (p<0.01), and T-cell receptor excision circle levels in T(reg) cells (p<0.01) were lower in CHF patients than in non-CHF controls. Combined annexin-V and 7-AAD staining showed that peripheral T(reg) cells from CHF patients exhibited increased spontaneous apoptosis and were more prone to interleukin (IL)-2 deprivation- and CD95 ligand-mediated apoptosis than those from non-CHF individuals. Furthermore, analyses by both flow cytometry and real-time polymerase chain reaction showed that T(reg)-cell frequency in the mediastinal lymph nodes or Foxp3 expression in hearts of CHF patients was no higher than that of the non-CHF controls.

CONCLUSION

Our data suggested that the T(reg)-cell defects of CHF patients were likely caused by decreased thymic output of nascent T(reg) cells and increased susceptibility to apoptosis in the periphery.

Regulatory T cells in cancer

At the present time, regulatory T cells (Tregs) are an integral part of immunology but the route from discovery of "suppressive" lymphocytes in the 1980s to the current established concept of Tregs almost 20 years later has been a rollercoaster ride. Tregs are essential for maintaining self-tolerance as defects in their compartment lead to severe autoimmune diseases. This vitally important function exists alongside the detrimental effects on tumor immunosurveillance and antitumor immunity. Beginning with the identification of CD4(+)CD25(+) Tregs in 1995, the list of Treg subsets, suppressive mechanisms, and knowledge about their various origins is steadily growing. Increase in Tregs within tumors and circulation of cancer patients, observed in early studies, implied their involvement in pathogenesis and disease progression. Several mechanisms, ranging from proliferation to specific trafficking networks, have been identified to account for their systemic and/or local accumulation. Since various immunotherapeutic approaches are being utilized for cancer therapy, various strategies to overcome the antagonistic effects exerted by Tregs are being currently explored. An overview on the biology of Tregs present in cancer patients, their clinical impact, and methods for modulating them is given in this review. Despite the extensive studies on Tregs in cancer many questions still remain unanswered. Even the paradigm that Tregs generally are disadvantageous for the control of malignancies is now under scrutiny. Insight into the specific role of Tregs in different types of neoplasias is the key for targeting them in a way that is beneficial for the clinical outcome.

Fludarabine modulates immune response and extends in vivo survival of adoptively transferred CD8 T cells in patients with metastatic melanoma

Background

Adoptive T cell therapy involving the use of ex vivo generated antigen-specific cytotoxic T lymphocytes provides a promising approach to immunotherapy. It has become increasingly apparent that anti-tumor efficacy using adoptively transferred T cells is linked to their duration of in vivo persistence and can only be achieved when combined with some form of pre-infusion patient conditioning regimen. An optimal conditioning regimen that provides a positive benefit without serious toxicities has yet to be defined. We have established a unique clinical model that allows for evaluation of a given conditioning regimen on adoptively transferred T cells in humans. In this first-in-human study (FHCRC #1796), we evaluate the use of fludarabine, an FDA-approved reagent with predictable lymphodepleting kinetics and duration of action, as a conditioning regimen that promotes homeostatic upregulation of cytokines and growth signals contributing to in vivo T cell persistence.

Methods/Findings

We conducted a phase I study in patients with refractory metastatic melanoma. Patients received two infusions of a single tumor-reactive antigen-specific CTL clone expanded to 10¹⁰/m²; the first infusion was given without fludarabine conditioning, and the second CTL infusion was given after a course of fludarabine (25 mg/m²/day×5 days). This design permits intra-patient comparison of in vivo T cell persistence pre- and post-fludarabine. Nineteen CTL infusions were administered to ten patients. No serious toxicities were observed. Three of nine evaluable patients experienced minor response or stable disease for periods of 5.8–11.0 months with two additional patients demonstrating delayed disease stabilization. The median overall survival in this heavily pre-treated population was 9.7 months. Fludarabine led to a 2.9 fold improvement in the in vivo persistence of transferred CTL clones from a median of 4.5 days (range 0–38+) to 13.0 days (range 2–63+) (p<0.05). Fludarabine lymphodepletion increased plasma levels of the homeostatic cytokines IL-7 and IL-15. Surprisingly, fludarabine also increased the relative percentage of CD4+ T cells expressing the regulatory protein Foxp3.

Conclusions/Significance

Lymphodepletion with fludarabine enhances transferred T cell persistence but suggest that additional improvements to optimize T cell survival and address regulatory T cells are critical in providing anti-tumor efficacy.

Trial Registration

ClinicalTrials.gov NCT00317759