Flow cytometric analysis of tumour infiltrating lymphocyte activation and tumour cell MHC class I and II expression in breast cancer patients

Targeting Pivotal Hallmarks of Cancer for Enhanced Therapeutic Strategies in Triple-Negative Breast Cancer Treatment-In Vitro, In Vivo and Clinical Trials Literature Review

This literature review provides a comprehensive overview of triple-negative breast cancer (TNBC) and explores innovative targeted therapies focused on specific hallmarks of cancer cells, aiming to revolutionize breast cancer treatment. TNBC, characterized by its lack of expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), presents distinct features, categorizing these invasive breast tumors into various phenotypes delineated by key elements in molecular assays. This article delves into the latest advancements in therapeutic strategies targeting components of the tumor microenvironment and pivotal hallmarks of cancer: deregulating cellular metabolism and the Warburg effect, acidosis and hypoxia, the ability to metastasize and evade the immune system, aiming to enhance treatment efficacy while mitigating systemic toxicity. Insights from in vitro and in vivo studies and clinical trials underscore the promising effectiveness and elucidate the mechanisms of action of these novel therapeutic interventions for TNBC, particularly in cases refractory to conventional treatments. The integration of targeted therapies tailored to the molecular characteristics of TNBC holds significant potential for optimizing clinical outcomes and addressing the pressing need for more effective treatment options for this aggressive subtype of breast cancer.

Triple-Negative Breast Cancer Intrinsic FTSJ1 Favors Tumor Progression and Attenuates CD8+ T Cell Infiltration

FtsJ RNA 2'-O-methyltransferase 1 (FTSJ1) is a member of the methyltransferase superfamily and is involved in the processing and modification of ribosomal RNA. We herein demonstrate that FTSJ1 favors TNBC progression. The knockdown of FTSJ1 inhibits TNBC cell proliferation and development, induces apoptosis of cancer cells, and increases the sensitivity of TNBC cells to T-cell-mediated cytotoxicity. Furthermore, the high expression of FTSJ1 in TNBC attenuates CD8+T cell infiltration in the tumor microenvironment (TME) correlated with poorer prognosis for clinical TNBC patients. In this study, we establish that FTSJ1 acts as a tumor promotor, is involved in cancer immune evasion, and may serve as a potential immunotherapy target in TNBC.

Tumor-Infiltrating Lymphocytes and Immune Response in HER2-Positive Breast Cancer

Human epidermal growth factor receptor 2-positive (HER2-positive) breast cancer accounts for 15 to 25% of breast cancer cases. Although therapies based on the use of monoclonal anti-HER2 antibodies present clinical benefit for a subtype of patients with HER2-positive breast cancer, more than 50% of them are unresponsive to targeted therapies or they eventually relapse. In recent years, reactivation of the adaptive immune system in patients with solid tumors has emerged as a therapeutic option with great potential for clinical benefit. Since the approval of the first treatment directed against HER2 as a therapeutic target, the range of clinical options has expanded greatly, and, in this sense, cellular immunotherapy with T cells relies on the cytotoxicity generated by these cells, which ultimately leads to antitumor activity. Lymphocytic infiltration of tumors encompasses a heterogeneous population of immune cells within the tumor microenvironment that exhibits distinct patterns of immune activation and exhaustion. The prevalence and prognostic value of tumor-infiltrating lymphocyte (TIL) counts are associated with a favorable prognosis in HER2-positive breast cancers. This review discusses emerging findings that contribute to a better understanding of the role of immune infiltrates in HER2-positive breast cancer. In addition, it summarizes the most recent results in HER2-positive breast cancer immunotherapy and anticipates which therapeutic strategies could be applied in the immediate future.

Radiomics features for assessing tumor-infiltrating lymphocytes correlate with molecular traits of triple-negative breast cancer

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) have become a promising biomarker for assessing tumor immune microenvironment and predicting immunotherapy response. However, the assessment of TILs relies on invasive pathological slides.

METHODS

We retrospectively extracted radiomics features from magnetic resonance imaging (MRI) to develop a radiomic cohort of triple-negative breast cancer (TNBC) (n = 139), among which 116 patients underwent transcriptomic sequencing. This radiomic cohort was randomly divided into the training cohort (n = 98) and validation cohort (n = 41) to develop radiomic signatures to predict the level of TILs through a non-invasive method. Pathologically evaluated TILs in the H&E sections were set as the gold standard. Elastic net and logistic regression were utilized to perform radiomics feature selection and model training, respectively. Transcriptomics was utilized to infer the detailed composition of the tumor microenvironment and to validate the radiomic signatures.

RESULTS

We selected three radiomics features to develop a TILs-predicting radiomics model, which performed well in the validation cohort (AUC 0.790, 95% confidence interval (CI) 0.638-0.943). Further investigation with transcriptomics verified that tumors with high TILs predicted by radiomics (Rad-TILs) presented activated immune-related pathways, such as antigen processing and presentation, and immune checkpoints pathways. In addition, a hot immune microenvironment, including upregulated T cell infiltration gene signatures, cytokines, costimulators and major histocompatibility complexes (MHCs), as well as more CD8⁺ T cells, follicular helper T cells and memory B cells, was found in high Rad-TILs tumors.

CONCLUSIONS

Our study demonstrated the feasibility of radiomics model in predicting TILs status and provided a method to make the features interpretable, which will pave the way toward precision medicine for TNBC.

Nomogram to Predict Tumor-Infiltrating Lymphocytes in Breast Cancer Patients

Background: Tumor-infiltrating lymphocytes (TILs) play important roles in the prediction of prognosis and neoadjuvant therapy (NAT) efficacy in breast cancer (BRCA) patients, in this study, we identified clinicopathological factors related to BRCA TILs, then to construct and validate nomogram to predict high density of TILs. Methods: A total of 826 patients diagnosed with BRCA in Sun Yat-Sen University cancer center were enrolled in nomogram cohort. TILs were assessed using hematoxylin-eosin (H&E) staining by two pathologists. Complete clinical data were collected for analysis. Then the enrolled patients were split into a training set and validation set at a ratio of 8:2. and the backward multivariate binary logistic regression model was used to establish nomogram for predicting BRCA TILs, which were further evaluated and validated using the C-index, receiver operating characteristic (ROC) curves and calibration curves. Then another independent NAT cohort of 106 patients was established for verifying this nomogram in NAT efficacy prediction. Results: TILs were significantly correlated with body mass index (BMI), tumor differentiation, ER, PR, HER2 expression, Ki67, blood biochemical indicators including total bilirubin (TBIL), indirect bilirubin (IBIL), total protein (TP), Globulin (GLOB), inorganic phosphorus (IP), calcium (Ca). In which ER expression level [OR = 0.987, 95%CI (0.982-0.992), p < 0.001], IP [OR = 4.462, 95%CI (1.171∼17.289), p = 0.029], IBIL [OR = 0.906, 95%CI (0.845-0.966), p = 0.004] and TP [OR = 1.053, 95%CI (1.010-1.098, p = 0.016)] were independent predictors of TILs. Then nomogram was established, for which calibration curves (C-index = 0.759) and ROC curve (AUC = 0.759, 95%CI 0.717-0.801) in training sets, calibration curves (C-index = 0.708) and ROC curve (AUC = 0.708, 95%CI 0.617-0.800) in validation sets demonstrated great evaluation efficiency. Besides, independent NAT cohort verified this nomogram can distinguish patients with greater NAT efficacy (p = 0.041). Conclusion: The finds of clinicopathological factors associated with TILs could help clinicians to understand the tumor immunity of BRCA and improve treatment system for patients, and the established nomogram with high evaluation efficiency may be used as a complement tool for distinguishing patients with better NAT efficacy.

Therapeutic Effect of Trastuzumab in Neoadjuvant-Treated HER2-Positive Breast Cancer with Low Infiltrating Level of Tumor-Infiltrating Lymphocytes

PURPOSE

The aim of the present study was to investigate the effect of trastuzumab on the pathological complete response (pCR) rate and event-free survival (EFS) in neoadjuvant-treated HER2-positive breast cancer with a low infiltrating level of tumor-infiltrating lymphocytes (TILs).

PATIENTS AND METHODS

The infiltrating level of TILs was evaluated in hematoxylin and eosin-stained slides from diagnostic needle biopsies, and a low infiltrating level of TILs was defined as TILs < 10%. Data of 179 HER2-positive patients with a low infiltrating level of TILs were retrospectively reviewed and compared according to whether trastuzumab was administered or not. The associations of clinicopathological characteristics with pCR or EFS were assessed in univariate and multivariate analyses. EFS was estimated by the Kaplan-Meier method and compared by the log rank test.

RESULTS

Of 179 patients, the overall pCR rate was 20.1%, and 74 patients (41.3%) received trastuzumab. Patients treated with trastuzumab showed a pCR rate of 20.3% compared with 20.0% for those without trastuzumab (P = 0.965). Trastuzumab administration was not associated with pCR in univariate (P = 0.965) and multivariate (P = 0.994) analyses. Negative status of hormone receptor (HR) (P < 0.001) and histological grade 3 (P = 0.007) were independent predictors for pCR in multivariate analyses. Trastuzumab usage had no significant impact on EFS in univariate (P = 0.916) and multivariate (P = 0.431) analyses, and pCR was the only independent predictor for favorable EFS (P = 0.012) in multivariate analyses.

CONCLUSION

In neoadjuvant-treated HER2-positive breast cancer with a low infiltrating level of TILs, additional trastuzumab had no significant influence on the pCR rate and EFS. HR-negative status and histological grade 3 were independently associated with higher pCR rates, and pCR was the only independent predictor for improved survival. Our findings may help identify patients who are resistant to trastuzumab, thereby guiding the de-escalating choice of anti-HER2 therapy.

Immunotherapy in breast cancer: Current status and future directions

Breast cancer, one of the leading causes of death in women in the United States, challenges therapeutic success in patients due to tumor heterogeneity, treatment resistance, metastasis and disease recurrence. Knowledge of immune system involvement in normal breast development and breast cancer has led to extensive research into the immune landscape of breast cancer and multiple immunotherapy clinical trials in breast cancer patients. However, poor immunogenicity and T-cell infiltration along with heightened immunosuppression in the tumor microenvironment have been identified as potential challenges to the success of immunotherapy in breast cancer. Oncodrivers, owing to their enhanced expression and stimulation of tumor cell proliferation and survival, present an excellent choice for targeted immunotherapy development in breast cancer. Loss of anti-tumor immune response specific to oncodrivers has been reported in breast cancer patients as well. Dendritic cell vaccines have been tested for their efficacy in generating anti-tumor T-cell response against specific tumor-associated antigens and oncodrivers and have shown improved survival outcome in patients. Here, we review the current status of immunotherapy in breast cancer, focusing on dendritic cell vaccines and their therapeutic application in breast cancer. We further discuss future directions of breast cancer immunotherapy and potential combination strategies involving dendritic cell vaccines and existing chemotherapeutics for improved efficacy and better survival outcome in breast cancer.

Impact of the Tumor Microenvironment on Tumor-Infiltrating Lymphocytes: Focus on Breast Cancer

Immunotherapy is revolutionizing cancer care across disciplines. The original success of immune checkpoint blockade in melanoma has already been translated to Food and Drug Administration-approved therapies in a number of other cancers, and a large number of clinical trials are underway in many other disease types, including breast cancer. Here, we review the basic requirements for a successful antitumor immune response, with a focus on the metabolic and physical barriers encountered by lymphocytes entering breast tumors. We also review recent clinical trials of immunotherapy in breast cancer and provide a number of interesting questions that will need to be answered for successful breast cancer immunotherapy.

Downregulation of antigen presentation-associated pathway proteins is linked to poor outcome in triple-negative breast cancer patient tumors

Triple-negative breast cancer (TNBC) is a heterogeneous subtype with varying disease outcomes. Tumor-infiltrating lymphocytes (TILs) are frequent in TNBC and have been shown to correlate with outcome, suggesting an immunogenic component in this subtype. However, other factors intrinsic to the cancer cells may also influence outcome. To identify proteins and molecular pathways associated with recurrence in TNBC, 34 formalin-fixed paraffin-embedded (FFPE) primary TNBC tumors were investigated by global proteomic profiling using mass spectrometry. Approximately, half of the patients were lymph node-negative and remained free of local or distant metastasis within 10 y follow-up, while the other half developed distant metastasis. Proteomic profiling identified >4,000 proteins, of which 63 exhibited altered expression in primary tumors of recurrence versus recurrence-free patients. Importantly, downregulation of proteins in the major histocompatibility complex (MHC) class I antigen presentation pathways were enriched, including TAP1, TAP2, CALR, HLA-A, ERAP1 and TAPBP, and were associated with significantly shorter recurrence-free and overall survival. In addition, proteins involved in cancer cell proliferation and growth, including GBP1, RAD23B, WARS and STAT1, also exhibited altered expression in primary tumors of recurrence versus recurrence-free patients. The association between the antigen-presentation pathway and outcome were validated in a second sample set of 10 primary TNBC tumors and corresponding metastases using proteomics and in a large public gene expression database of 249 TNBC and 580 basal-like breast cancer cases. Our study demonstrates that downregulation of antigen presentation is a key mechanism for TNBC cells to avoid immune surveillance, allowing continued growth and spread.

Breast Cancer Immunology and Immunotherapy: Current Status and Future Perspectives

Cancer immunology has gained renewed interest in the past few years due to emerging findings on mechanisms involved in tumoral immune evasion. Indisputably, immune edition is currently considered a critical hallmark of cancer. Basic research has revealed new targets which can be modulated in the clinical setting with new compounds and strategies. As recent evidence confirms, breast cancer (BC) is a complex and heterogeneous disease in which host immune responses play a substantial role. T-infiltrating lymphocytes measurement is suggested as a powerful new tool necessary to predict early BC evolution, especially in HER2-positive and triple negative subtypes. However, T-infiltrating lymphocytes, genomic platforms, and many other biomarkers in tissue and peripheral blood (e.g., regulatory T cells and myeloid-derived suppressor cells) are not the only factors being evaluated regarding their potential role as prognostic and/or predictive factors. Many ongoing clinical trials are exploring the activity of immune checkpoint modulators in BC treatment, both in the advanced and neoadjuvant setting. Although this field is expanding with exciting new discoveries and promising clinical results-and creating great expectations-there remain many uncertainties yet to be addressed satisfactorily before this long awaited therapeutic promise can come to fruition.

Altered Expression of Natural Cytotoxicity Receptors and NKG2D on Peripheral Blood NK Cell Subsets in Breast Cancer Patients

Human natural killer (NK) cells are considered professional cytotoxic cells that are integrated into the effector branch of innate immunity during antiviral and antitumoral responses. The purpose of this study was to examine the peripheral distribution and expression of NK cell activation receptors from the fresh peripheral blood mononuclear cells of 30 breast cancer patients prior to any form of treatment (including surgery, chemotherapy, and radiotherapy), 10 benign breast pathology patients, and 24 control individuals. CD3⁻CD56^dimCD16^bright NK cells (CD56^dim NK) and CD3⁻CD56^brightCD16^dim/− NK cells (CD56^bright NK) were identified using flow cytometry. The circulating counts of CD56^dim and CD56^bright NK cells were not significantly different between the groups evaluated, nor were the counts of other leukocyte subsets between the breast cancer patients and benign breast pathology patients. However, in CD56^dim NK cells, NKp44 expression was higher in breast cancer patients (P = .0302), whereas NKp30 (P = .0005), NKp46 (P = .0298), and NKG2D (P = .0005) expression was lower with respect to healthy donors. In CD56^bright NK cells, NKp30 (P = .0007), NKp46 (P = .0012), and NKG2D (P = .0069) expression was lower in breast cancer patients compared with control group. Only NKG2D in CD56^bright NK cells (P = .0208) and CD56^dim NK cells (P = .0439) showed difference between benign breast pathology and breast cancer patients. Collectively, the current study showed phenotypic alterations in activation receptors on CD56^dim and CD56^bright NK cells, suggesting that breast cancer patients have decreased NK cell cytotoxicity.

Clinical relevance of host immunity in breast cancer: from TILs to the clinic

The clinical relevance of the host immune system in breast cancer has long been unexplored. Studies developed over the past decade have highlighted the biological heterogeneity of breast cancer, prompting researchers to investigate whether the role of the immune system in this malignancy is similar across different molecular subtypes of the disease. The presence of high levels of lymphocytic infiltration has been consistently associated with a more-favourable prognosis in patients with early stage triple-negative and HER2-positive breast cancer. These infiltrates seem to reflect favourable host antitumour immune responses, suggesting that immune activation is important for improving survival outcomes. In this Review, we discuss the composition of the immune infiltrates observed in breast cancers, as well as data supporting the clinical relevance of host antitumour immunity, as represented by lymphocytic infiltration, and how this biomarker could be used in the clinical setting. We also discuss the rationale for enhancing immunity in breast cancer, including early data on the efficacy of T-cell checkpoint inhibition in this setting.

Current perspectives of molecular pathways involved in chronic inflammation-mediated breast cancer

Inflammation has multifaceted role in cancer progression including initiation, promotion and invasion by affecting the immune surveillance and associated signaling pathways. Inflammation facilitates the over-expression of cytokines, chemokines and growth factors involved in progression of different cancers including breast cancer progression. Deregulation of biological processes such as oxidative stress, angiogenesis, and autophagy elicit favorable immune response towards chronic inflammation. Apart from the role in carcinogenesis, chronic inflammation also favors the emergence of drug resistance clones by inducing the growth of breast cancer stem-like cells. Immunomodulation mediated by cytokines, chemokines and several other growth factors present in the tumor microenvironment regulate chronic inflammatory response and alter crosstalk among various signaling pathways such as NF-κB, Nrf-2, JAK-STAT, Akt and MAPKs involved in the progression of breast cancer. In this review, we focused on cellular and molecular processes involved in chronic inflammation, crosstalk among different signaling pathways and their association in breast cancer pathogenesis.

Prognostic significance of CD8+ T lymphocytes in breast cancer depends upon both oestrogen receptor status and histological grade

AIMS

Results of previous studies on the influence of tumour infiltrating lymphocytes on prognosis of women with breast cancer have been mixed. This study re-evaluates the role of tumour-infiltrating lymphocytes as a prognostic marker in women with breast cancer.

METHODS AND RESULTS

Immunochemistry staining of CD8(+) T cells was performed on a tissue microarray of 1953 breast carcinomas. When all tumours were considered, no association between the lymphocyte count and patient survival was found. In univariate analysis, there was a reduced disease-specific survival for women with oestrogen receptor (ER)-positive tumours with high intraepithelial lymphocyte count (P=0.004). In those with ER-negative tumours, the disease-specific survival was improved when the intraepithelial, stromal and total lymphocyte counts were high, the total lymphocyte count also being an independent prognostic marker on multivariate analysis (P=0.031). When stratified by histological grade, on univariate analysis, the previously observed inferior outcome in women with high lymphocyte count and ER-positive tumours remained significant only if tumours were also of low grade, and the superior outcome in those with ER-negative tumours remained significant if tumours were also of high grade.

CONCLUSIONS

Our results raise the possibility of different immune-tumour interactions based on ER status and histological grade.

Identification of novel tumor antigens with patient-derived immune-selected antibodies

The identification of tumor antigens capable of eliciting an immune response in vivo may be an effective method to identify therapeutic cancer targets. We have developed a method to identify such antigens using frozen tumor-draining lymph node samples from breast cancer patients. Immune responses in tumor-draining lymph nodes were identified by immunostaining lymph node sections for B-cell markers (CD20&CD23) and Ki67 which revealed cell proliferation in germinal center zones. Antigen-dependent somatic hypermutation (SH) and clonal expansion (CE) were present in heavy chain variable (VH) domain cDNA clones obtained from these germinal centers, but not from Ki67 negative germinal centers. Recombinant VH single-domain antibodies were used to screen tumor proteins and affinity select potential tumor antigens. Neuroplastin (NPTN) was identified as a candidate breast tumor antigen using proteomic identification of affinity selected tumor proteins with a recombinant VH single chain antibody. NPTN was found to be highly expressed in approximately 20% of invasive breast carcinomas and 50% of breast carcinomas with distal metastasis using a breast cancer tissue array. Additionally, NPTN over-expression in a breast cancer cell line resulted in a significant increase in tumor growth and angiogenesis in vivo which was related to increased VEGF production in the transfected cells. These results validate NPTN as a tumor-associated antigen which could promote breast tumor growth and metastasis if aberrantly expressed. These studies also demonstrate that humoral immune responses in tumor-draining lymph nodes can provide antibody reagents useful in identifying tumor antigens with applications for biomarker screening, diagnostics and therapeutic interventions.

Inflammation and breast cancer. Balancing immune response: crosstalk between adaptive and innate immune cells during breast cancer progression

Recent insights into the molecular and cellular mechanisms underlying cancer development have revealed that immune cells functionally regulate epithelial cancer development and progression. Moreover, accumulated clinical and experimental data indicate that the outcome of an immune response toward an evolving breast neoplasm is largely determined by the type of immune response elicited. Acute tumor-directed immune responses involving cytolytic T lymphocytes appear to protect against tumor development, whereas immune responses involving chronic activation of humoral immunity, infiltration by Th2 cells, and protumor-polarized innate inflammatory cells result in the promotion of tumor development and disease progression. Herein we review this body of literature and summarize important new findings revealing the paradoxical role of innate and adaptive leukocytes as regulators of breast carcinogenesis.

The immunophenotype and activation status of the lymphocytic infiltrate in human breast cancers, the role of the major histocompatibility complex in cell-mediated immune mechanisms, and their association with prognostic indicators

BACKGROUND

The aims of this study were to characterize, phenotypically, the immune infiltrate in human breast cancers, to assess the activation status of tumor-infiltrating lymphocytes (TIL), and to define the association of these findings with established prognostic indicators.

METHODS

Immunohistochemistry was performed on frozen sections of 60 primary breast cancers by use of monoclonal antibodies to T lymphocytes (CD3), T-helper cells (CD4), cytotoxic T-cells (CD8), natural killer cells (CD56), interleukin-2 receptors (IL-2R), and major histocompatibility (MHC) class I antigen (HLA-ABC) and MHC class II antigen (HLA-DR).

RESULTS

All tumors stained positive for CD3, CD4 and CD8, but with marked variation in the intensity of the infiltrate. In tumors with a moderate infiltrate of TIL, there was a trend toward a greater representation of T-helper cells. However, as the intensity of TIL increased, there was a decline in the proportion of T-helper cells and a concomitant rise in the relative proportion of cytotoxic T cells. There was a relative paucity of natural killer cells. A significant association was found between the intensity of TIL and the number of positive nodes (P=.02) and the intensity of the infiltrate of both T-helper cells and cytotoxic T cells with ER expression (P=.03 and.05, respectively). Most tumors stained positive for IL-2R. The expression of IL-2R was associated with the intensity of TIL (P<.0001), T-helper cells (P<.002), cytotoxic T cells (P=.01) and natural killer cells (P=0.04), and also with the degree of lymph node positivity (P=.02) and histologic tumor grade (P=.05). MHC class II expression was variable, and a large proportion of the tumors showed limited expression in individual cancer cells. There was an association between the expression of HLA-DR in tumor cells and the activation status of TIL (P=.03).

CONCLUSION

An immune infiltrate is an invariable finding in breast cancers, and the intensity of the infiltrate is greater in node positive tumors. Additionally, TIL may well be activated, albeit partially, in most tumors, suggesting that cell-mediated immune mechanisms are functionally intact.

RCAS1 is associated with ductal breast cancer progression

RCAS1/EBAG9 (receptor-binding cancer antigen expressed on SiSo cells/ estrogen receptor-binding fragment-associated gene 9), an estrogen-transcribed protein, has been shown to be expressed in a wide variety of cancers, including uterine, ovarian, and lung cancer cells. Soluble and membranous RCAS1 proteins may play a role in the immune escape of tumor cells by promoting T lymphocyte inhibition of growth and apoptosis. In the present report, the presence of RCAS1 was revealed in human ductal breast cancer biopsies by immunohistochemistry. Its cytoplasmic expression was exhibited in cancer cells obtained from tumor biopsies and in breast cancer cell lines. RCAS1 significantly correlated with tumor grade. In addition, RCAS1 was identified in MCF7 culture supernatants. Those observations suggest that RCAS1 is a new marker for breast cancer progression and a possible mechanism for breast cancer immune escape.

Breast cancer and the immune system: opportunities and pitfalls

The identification of tumor-associated antigens, and advances in our understanding of human immunology, have resulted in renewed interest in tumor immunology. A variety of approaches have been utilized in recent years against different tumor types. The results from some of these studies have been encouraging, but it is not yet clear whether they will be applicable to patients with breast cancer.

Positive and negative consequences of soluble Fas ligand produced by an antigen-specific CD4(+) T cell response in human carcinoma immune interactions

The influence of a human CD4(+) T cell response in anti-carcinoma immune reactions remains largely uncharacterized. Here, we made use of a major histocompatibility complex (MHC) class-II-restricted, anti-ras oncogene-specific CD4(+) T cell line produced previously in vivo from a patient with metastatic carcinoma in a peptide-based phase I trial. Using this patient-derived T cell line as a potentially relevant cell type, we examined the consequences of the anti-carcinoma CD4(+) T cell response, with emphasis on specific lymphokines potentially important for the regulation of Fas/Fas ligand (FasL) interactions. Antigen (Ag)-specific CD4(+) T cells produced substantial amounts of IFN-gamma following recognition of MHC class-II-matched Ag-presenting cells expressing the cognate peptide. The IFN-gamma promoted significant upregulation of Fas on the surface of colon carcinoma cells and sensitized these targets to Fas-mediated apoptosis and Ag-specific CD8(+) cytotoxic T lymphocyte (CTL)-mediated lysis involving a Fas-based effector mechanism. Moreover, Ag-stimulated CD4(+) T cells secreted soluble FasL (sFasL), which induced the death of TNF-resistant/refractory colon, breast, and ovarian carcinoma cells. Interestingly, although CD4(+)-derived sFasL expressed cytotoxic activity, the recovery of carcinoma cells which resisted Fas-mediated lysis displayed enhanced metastatic ability in vivo, compared with the unselected parental population, in an athymic mouse model. Thus, a tumor-specific CD4(+) T cell response may have both positive and negative consequences in human carcinoma via the production of proinflammatory cytokines such as IFN-gamma and/or sFasL that may (1) improve or facilitate CTL-target engagement, contact-independent effector mechanisms, and the overall lytic outcome and (2) potentially select for Fas-resistant tumor cells that escape immune destruction, which may thus impact the metastatic process.

Autologous graft-versus-host disease induction in advanced breast cancer: role of peripheral blood progenitor cells

The purpose of the present study was to investigate the impact of the use of peripheral blood progenitor cells (PBPCs) on the induction of autologous graft-versus-host disease (GVHD) in patients with advanced breast cancer. 14 women with stage IIIB and 36 women with stage IV breast cancer received cyclosporine (CsA) 2.5 mg kg-1 i.v. daily, d 0-28, and interferon-gamma (IFNg) 0.025 mg/m2 s.c. qod, d7-28, following PBPC-T +/- bone marrow transplantation (BMT). Preceding high-dose chemotherapy consisted of cyclophosphamide 6 g/m2 and thiotepa 800 mg/m2. Histologically proven > or = grade II cutaneous GVHD was induced in18/50 (36%) of patients and was independent of the source of haematopoietic support. In vitro studies showed that post-transplant, 76% of patients had developed auto-cytotoxicity against their own pre-transplant PHA-lymphoblasts. A significant correlation between the occurrence of GVHD > or = grade II and cytolysis was observed in the NK cell-line K562 and the T47D breast cancer cell-line. With a median follow-up of 2(1/2) years, the overall survival (OS) is 58%, the disease-free survival (DFS) 26%, both independent of the development of GVHD and similar to what has been observed in other studies on high-dose chemotherapy in advanced breast cancer. It therefore remains unclear whether the induction of autologous GVHD with the occurrence of auto-cytotoxic lymphocytes can result in an anti-tumour effect in this group of patients.

Immunohistochemical analysis of primary breast tumors and tumor-draining lymph nodes by means of the T-cell costimulatory molecule OX-40

OBJECTIVES

The OX-40 receptor (OX-40R/CD134) is expressed primarily on activated CD4(+) ("helper") T cells. We have previously reported the presence of OX-40(+) T cells in head and neck cancer and melanoma, where they appear to be restricted to tumor compartments (primary tumor infiltrating lymphocytes [TILs] and draining lymph node cells) and therefore may represent the tumor antigen-specific CD4(+) T cells.

METHODS

In order to determine the degree of OX-40R expression, and any relationship with the presence of tumor cells (lobular and/or infiltrating ductal carcinoma), 45 archived paraffin-embedded breast primary tumors and their associated draining (axillary) lymph nodes were retrospectively analyzed using standard immunohistochemical techniques.

RESULTS

Seven of 45 primary tumors (16%) and 7 of 29 with lympocytic infiltrates (24%) were noted to have elevated levels of OX-40R(+) lymphocytes within the tumor specimens, including 2 of 4 specimens thought to have only "pure" ductal carcinoma in situ (DCIS). No OX-40R(+) lymphocytes were noted in normal breast tissue. Twenty-one (43%) patients had axillary metastases at the time of resection. High levels of OX-40R expression was seen in 9 (45%) of these 21 axillary node specimens, whereas no such staining was seen in the node-negative specimens (P <0.001). Furthermore, in a patient thought to be without axillary disease, several subcapsular single-cell metastases were retrospectively discovered near a lone cluster of OX-40R(+) lymphocytes. In general, visual inspection showed OX-40R(+) T cells to be in close proximity to tumor and often in direct contact with metastatic cells.

CONCLUSIONS

The OX-40R is upregulated on lymphocytes within tumor draining lymph nodes, and these lymphocytes are specifically localized around tumor deposits. These data imply that OX-40R immunostaining may be useful for both determination of occult involvement of lymph nodes by tumor and for identification of potential candidates for future OX-40 based immunotherapy.

Functional down-regulation of beta1 and beta2 integrins of lamina propria lymphocytes (LPL) and tumor-infiltrating lymphocytes (TIL) in colorectal cancer patients

Integrins play an important role in various lymphocyte functions. In this study, we isolated lamina propria lymphocytes (LPL) and tumor-infiltrating lymphocytes (TIL) from normal and malignant tissues in patients with colorectal cancer, and examined the expression of beta1 and beta2 integrins on these lymphocytes quantitatively with two-color flow cytometry. Both LPL and TIL expressed a lower level of common beta1 chain (CD29) in CD4 and CD8 subpopulations than did peripheral blood lymphocytes (PBL). Among the associated alpha chains, the expression levels of alpha1 (CD49a) and alpha2 (CD49b) were slightly higher, whereas those of alpha4 (CD49d) and alpha6 (CD49f) were markedly reduced in LPL and TIL. No significant differences were observed in expressions of any alpha1 integrin chains between these two lymphocytes populations. Similarly, both alphaL (CD11a) and beta2 (CD18) were down-regulated in TIL and LPL with CD8+ cytotoxic phenotype, but not in those with CD4+ phenotype. CD8+ TIL expressed a slightly but significantly higher level of alphaLbeta2 than did CD8+ LPL. CD8+ LPL and CD8+ TIL consistently showed significantly decreased binding to purified ICAM-1, VCAM-1 and HT29 colon cancer cells as compared with CD8+ PBL. Although CD8+ TIL showed a slightly higher level of adhesion to these substrates than did CD8+ LPL, the level was much lower than that in PBL. The expression pattern and functional down-regulation of these integrins may be one of the reasons why TIL cannot eradicate the cancer cells in colorectal cancer.

Growth and antigen recognition of tumor-infiltrating lymphocytes from human breast cancer

In the present study, we isolated tumor-infiltrating lymphocytes (TIL) from 21 primary solid tumors and tumor-associated lymphocytes (TAL) from 9 malignant effusions, respectively, of breast cancer patients. Significant proliferation and expansion of T cells was observed in 23 of 30 distinct samples. TIL were isolated from primary tumors by either enzymatic digestion or mechanical disruption. The TIL cultures were initiated using OKT3 mAb in the presence of moderate concentrations (25-50 U/ml) of IL-2, followed by 100 U/ml of tumor necrosis factor (TNF)-alpha. TAL were not stimulated with OKT3 mAb, but all were successfully expanded in culture in the presence of IL-2 alone or together with TNF-alpha. Seven of nine distinct TAL grew in culture as predominantly CD4+ lines. In contrast, only 14 of 21 (66%) of primary breast TIL expanded in culture and were predominantly of CD8+ phenotype. Autologous tumor lysis was observed in seven of eight cases tested. Only one of the four TIL tested and one of the four TAL tested preferentially lysed autologous tumor. HER-2 peptide E75 (369-377) was recognized by two TIL lines of the five primary TIL tested and three of the four TAL tested. This suggests that E75 may be recognized by primary breast tumors. This may be of interest in developing vaccine strategies for therapeutic management of breast cancer.

Various functions of PBMC from colon cancer patients are not decreased compared to healthy blood donors

The immune surveillance hypothesis suggests impaired immune responses to participate in development of cancer. This may partly be due to increased amounts of PGE2 and histamine, which inhibit cellular immunity. These effects are mediated by cAMP, which is increased and thereby may down-regulate IL-2 and its receptor proteins in T helper cells. The proliferative responses and IL-2 synthesis of PBMC have earlier been shown to be reduced in patients with colon cancer. Recently immune modulating agents have been demonstrated to increase the proliferative response of PBMC in vitro, probably by inhibition of adenylate cyclase activity and induction of IL-2 mRNA expression. We have therefore studied the proliferative responses of PBMC from colon cancer patients to PWM and tested the effect of immune modulating agents, such as Serotonin, Sumatriptan, and Buspirone on these PBMC. We found no difference in levels of intracellular cAMP, IL-2 mRNA expression, IL-2R mRNA expression, or proliferative responses of PBMC from colon cancer patients compared to healthy blood donors. There was no effect of the immune modulating agents on PBMC from colon cancer patients.

High incidence of interleukin 10 mRNA but not interleukin 2 mRNA detected in human breast tumours

Despite the presence of a lymphocytic infiltrate in solid cancers, the failure for tumour growth to be contained suggests an inadequate immune response to the tumour. Poor cytotoxicity exerted by tumour-infiltrating lymphocytes (TILs) against tumour cells in vitro, combined with continued tumour growth in vivo, suggests deficiencies in TIL function or numbers. Various theories have been postulated to explain how tumour cells may escape immunosurveillance and control. One of the many hypotheses is the failure of production of cytokines, which are necessary for T cells to mediate their function. Thus, the expression of cytokine mRNA in human breast tumour sections was investigated by reverse transcriptase polymerase chain reaction (RT-PCR) with cytokine-specific primers. A relatively consistent finding was detection of interleukin (IL) 10 mRNA among the tumours. No IL-2 and little IL-4 mRNA was detected in the tumours. IL-6 and IL-10 mRNA was detected in only one and two of the normal breast tissues respectively. IL-2, IL-4 and tumour necrosis factor (TNF)-alpha mRNA was not detected in any of the normal breast tissues. The reduced function of TILs may be related to IL-10, which has known inhibitory effects on T-cell activation.

Interactions between interferon gamma and retinoic acid with transforming growth factor beta in the induction of immune recognition molecules

The cell-surface expression of major histocompatibility (MHC) antigens and the adhesion molecule intercellular adhesion molecule 1 (ICAM-1) is essential for target cell recognition by T lymphocytes. The expression of both classes of molecule is induced by various cytokines, notably interferon gamma (IFN gamma). Since transforming growth factor beta (TGF beta) has been recently reported to antagonise HLA-DR induction by IFN gamma we have examined, using a number of murine and human cell lines, the effect of TGF beta on IFN gamma-induced MHC class I and class II and ICAM-1 expression. All of the cell lines tested expressed elevated class I MHC following IFN gamma treatment. Class II MHC induction was seen on most but not all of the cells, the exceptions being among a panel of human colorectal carcinoma cell lines. A striking difference between cells of different origin was noted in the response to TGF beta. TGF beta was found to antagonise IFN gamma-induced class I and class II MHC expression on C3H 10T1/2 murine fibroblasts, early-passage BALB/c mouse embryo fibroblasts, a murine oligodendroglioma cell line, and on MRC5 human fibroblasts and two human glioblastoma cell lines. Class II MHC was much more strongly inhibited (sometimes completely) than class I MHC. TGF beta also inhibited induction of class I MHC expression by IFN alpha. However, TGF beta did not inhibit class I or class II MHC induction by IFN gamma in any of the nine colorectal carcinoma cell lines, although two of five of the lines tested were growth-inhibited by TGF beta. On the other hand, human ICAM-1 induction by IFN gamma was not affected by simultaneous treatment with TGF beta in any of the cell lines. The down-regulation of IFN gamma-induced MHC antigens by TGF beta is not, therefore, the result of a general antagonism of IFN gamma. Retinoic acid has recently been reported to induce ICAM-1 expression on human tumour cells. We have confirmed this observation on MRC5, and the two human glioblastoma cell lines, however six colorectal carcinoma cell lines tested did not respond. In contrast to IFN gamma-induced ICAM-1 expression, retinoic-acid-induced ICAM-1 expression was inhibited by TGF beta on two of the three responsive lines.

Analysis of clonality of tumour infiltrating lymphocytes in breast cancer and uveal melanoma

Fresh tumour infiltrating lymphocytes (TILs) from 6 uveal melanomas and 4 breast cancers were analysed by flow cytometry with a panel of 6 monoclonal antibodies to V beta regions of the T cell receptor (V betas 5a, 5b, 5c, 6, 8a and 12a). With a single exception where one TIL sample lacked V beta 12a, lymphocytes from both tumour and blood contained cells reactive with all 6 probes, and no probe was highly dominant or missing. The proportions of reactive cells differed between tumour and blood within each patient. The data indicate that while tumour infiltrating lymphocytes have a capacity to locate selectively within the tumour they nonetheless comprise a population expressing a diversity of TCR V beta genes.