Mononuclear cells infiltrating human mammary carcinomas: immunohistochemical analysis with monoclonal antibodies

Gains and Losses of HLA Class II (DR) and CD4 in Atypical Hyperplasia, Carcinoma in situ and Infiltrating Ductal Carcinoma of the Breast

Aim: Breast cancer is a frequent cause of death among women with gynaecologic malignancies despite the introduction of combination chemotherapy. There is therefore a need for new therapeutic strategies for patients with breast cancer, such as cellular immunotherapy. In this immunohistochemical study we analyzed the epithelial expression of major histocompatibility complex (MHC) class II (HLA-DR) on atypical and malignant primary mammary epithelial cells, as well as the magnitude of the stromal T lymphocytes (T4 subset) at the tumor site. Experimental design: The study was carried out retrospectively in tumor tissue from 82 patients with mammary lesions (31 cases of atypical ductal hyperplasia -ADH-, 12 cases of ductal carcinoma in situ –DCIS- and 39 cases of infiltrating ductal carcinoma not otherwise specified -IDC-NOS). Medullary carcinomas were not included in our investigation. Material used had been formalin fixed and paraffin embedded. Results: HLA class II (DR) was expressed in 20 of 31 ADHs (64.5%), in 4 of 12 DCISs (33.3%), and in 10 of 39 IDC-NOSs (25.6%). CD4 was expressed in 9 of 31 ADHs (29%), in 5 of 12 DCISs (42%), and in 26 of 39 IDCNOSs (67%). Conclusions: The results showed decreased epithelial expression of HLA class II (DR) and increased stromal expression of CD4, as the lesion progressed to malignancy. Gradual loss of epithelial HLA class II expression might be a manifestation of cellular differentiation from the atypical form versus the malignant one, signaling simultaneously a selective effect on the response capacity of the immune system.

Adaptive immunity programmes in breast cancer

The role of the immune system in shaping cancer development and patient prognosis has recently become an area of intense focus in industry and academia. Harnessing the adaptive arm of the immune system for tumour eradication has shown great promise in a variety of tumour types. Differences between tissues, however, necessitate a greater understanding of the adaptive immunity programmes that are active within each tumour type. In breast cancer, adaptive immune programmes play diverse roles depending on the cellular infiltration found in each tumour. Cytotoxic T lymphocytes and T helper type 1 cells can induce tumour eradication, whereas regulatory T cells and T helper type 2 cells are known to be involved in tumour-promoting immunosuppressive responses. Complicating these matters, heterogeneous expression of hormone receptors and growth factors in different tumours leads to disparate, patient-specific adaptive immune responses. Despite this non-conformity in adaptive immune behaviours, encouraging basic and clinical results have been observed that suggest a role for immunotherapeutic approaches in breast cancer. Here, we review the literature pertaining to the adaptive immune response in breast cancer, summarize the primary findings relating to the breast tumour's biology, and discuss potential clinical immunotherapies.

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.

Gene expression profiling and histopathological characterization of triple-negative/basal-like breast carcinomas

INTRODUCTION

Breast cancer is a heterogeneous group of tumors, and can be subdivided on the basis of histopathological features, genetic alterations and gene-expression profiles. One well-defined subtype of breast cancer is characterized by a lack of HER2 gene amplification and estrogen and progesterone receptor expression ('triple-negative tumors'). We examined the histopathological and gene-expression profile of triple-negative tumors to define subgroups with specific characteristics, including risk of developing distant metastases.

METHODS

97 triple-negative tumors were selected from the fresh-frozen tissue bank of the Netherlands Cancer Institute, and gene-expression profiles were generated using 35K oligonucleotide microarrays. In addition, histopathological and immunohistochemical characterization was performed, and the findings were associated to clinical features.

RESULTS

All triple-negative tumors were classified as basal-like tumors on the basis of their overall gene-expression profile. Hierarchical cluster analysis revealed five distinct subgroups of triple-negative breast cancers. Multivariable analysis showed that a large amount of lymphocytic infiltrate (HR = 0.30, 95% CI 0.09-0.96) and absence of central fibrosis in the tumors (HR = 0.14, 95% CI 0.03-0.62) were associated with distant metastasis-free survival.

CONCLUSION

Triple-negative tumors are synonymous with basal-like tumors, and can be identified by immunohistochemistry. Based on gene-expression profiling, basal-like tumors are still heterogeneous and can be subdivided into at least five distinct subgroups. The development of distant metastasis in basal-like tumors is associated with the presence of central fibrosis and a small amount of lymphocytic infiltrate.

Roles of the innate immune system in mammary gland remodeling during involution

Mammary gland involution is a period of intensive tissue remodeling. Over the course of a relatively brief period, a large proportion of the mammary gland epithelium undergoes programmed cell death and is removed by phagocytes. In addition, the gland is cleared of residual milk fat globules as well as milk and adipocytes become the predominant cell type. The role of the immune system in this process has not been clearly defined. Professional phagocytes derived from the immune system can participate in the clearance of apoptotic and autophagic cells, the removal of residual milk components, and the prevention of mastitis during mammary gland involution. However, many of these functions can also be performed by non-professional phagocytes (e.g. mammary epithelial cells). This review will discuss the evidence that supports a role for innate immune cells in mammary gland remodeling during involution.

Prospective study on the expression of cancer testis genes and antibody responses in 100 consecutive patients with primary breast cancer

To determine the expression of cancer testis (CT) genes and antibody responses in a nonselected population of patients with primary breast cancer, we investigated the composite expression of 11 CT genes by RT-PCR in fresh biopsies of 100 consecutive cases of primary breast carcinoma and by immunohistology in selected RT-PCR-positive cases. Antibody responses against 7 CT antigens were analyzed using recombinant antigen expression on yeast surface. In 98 evaluable cases, SCP-1 and SSX-4 were expressed most frequently (both 65%), followed by HOM-TES-85/CT-8 (47%), GAGE (26%), SSX-1 (20%), NY-ESO-1 (13%), MAGE-3 (11%), SSX-2 (8%), CT-10 (7%), MAGE-4 (4%) and CT-7 (1%). One CT gene was expressed by 90% of the cases; 79% expressed > or =2, 48% > or =3, 29% > or =4, 12% > or =5, 6% > or =6, 3% > or =7, 2% > or =8 and one case coexpressed 9 antigens. Of 100 serum samples screened for CT antigen-specific antibodies, antibodies against NY-ESO-1 were detected in 4 patients, against SCP-1 in 6 patients and against SSX-2 in 1 patient, while no antibodies were detected against MAGE-3, CT-7 and CT-10. Expression of CT genes or antibody responses was not correlated with clinical parameters (menopausal status, tumor size, nodal involvement, grading, histology and estrogen receptor status) or the demonstration of CT gene expression at the protein level, by immunohistology. Our results show that breast carcinomas are among the tumors with the most frequent expression of CT antigens, rendering many patients potential candidates for vaccine trials.

Versatile Prostate Cancer Treatment with Inducible Caspase and Interleukin-12

To establish optimized conditions for immunity against prostate cancer, we compared the efficacy of multiple approaches in autochthonous and s.c. transgenic adenocarcinoma of the mouse prostate (TRAMP)-based models. Mice immunized with interleukin (IL)-12-containing apoptotic, but not necrotic TRAMP-C2 cell-based, vaccines were resistant to TRAMP-C2 tumor challenge and re-challenge, independently of the route of vaccination (s.c. or i.p.). Administration of gamma-irradiated TRAMP-C2 cells preinfected with adenovirus containing both B7-1 and IL-12 genes, unlike adenovirus containing B7-1 alone, considerably protected C57BL/6 mice from TRAMP-C2 tumor growth and extended the life span of TRAMP mice. Vaccines that included dendritic cells, instead of IL-12, were equally efficient. Whereas injections of ligand-inducible caspase-1- and IL-12-containing adenoviruses cured small s.c. TRAMP-C2 tumors, nanopump-regulated delivery of viruses led to elimination of much larger tumors. The antitumor immune responses involved CD4+-, CD8+-, and natural killer cells and were strengthened by increasing the number of vaccinations. Intraprostatic administration of inducible caspase-1- and IL-12-containing adenoviruses resulted in local cell death and improved survival of adenocarcinoma-bearing TRAMP mice. Thus, tumor cell apoptosis induced by caspase in situ and accompanied by IL-12 is efficient against prostate cancer in a preclinical model.

Targeted therapy of solid malignancies via HLA class II antigens: a new biotherapeutic approach?

Intracellular signals, delivered in professional antigen-presenting cells following the engagement of major histocompatibility complex (MHC) class II molecules, activate a variety of cellular functions that also contribute to efficient antigen presentation. As far as human malignancies, the signaling ability of human leukocyte antigens (HLA) class II molecules is a rather well-characterized event in hematologic tumors; in contrast, very limited evidences are available in solid neoplasias of different histotypes that may constitutively express HLA class II antigens. Among solid malignancies, a significant proportion of human cutaneous melanomas have been shown to express HLA class II molecules, and cutaneous melanoma undoubtedly represents a 'model disease' to investigate tumor immunobiology, to unveil the molecular basis underlying the interactions between neoplastic cells and host's immune system, and ultimately to set up new bio-immunotherapeutic approaches. Upcoming preclinical evidences unveil a signaling potential of HLA-DR antigens expressed on melanoma cells, and suggest for the clinical implication of HLA class II molecules as novel therapeutic targets. Therefore, in this review, we will focus on the emerging role of HLA class II antigens as intracellular signal transducing elements in neoplastic cells of the melanocytic lineage, emphasizing their foreseeable role in targeted therapy of human melanoma and potentially of HLA class II antigens-positive tumors of different histology.

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.

HLA-DR and beta 2 microglobulin expression in medullary and atypical medullary carcinoma of the breast: histopathologically similar but biologically distinct entities

AIMS

To examine the expression of HLA-DR and beta 2 microglobulin in medullary carcinoma and atypical medullary carcinoma of the breast to determine if the effective presentation of tumour antigens to the immune system can differentiate between these two histopathologically similar entities.

METHODS

Expression of HLA-DR and beta 2 microglobulin was examined by immunohistochemical methods in five samples of medullary carcinoma of the breast, which has a relatively favourable prognosis, six samples of atypical medullary carcinoma of the breast, which has a prognosis closer to that of regular invasive duct carcinoma, and 20 samples of invasive duct carcinomas, 10 with an accompanying lymphocytic infiltrate.

RESULTS

A positive and significant correlation was found between tumour type and both HLA-DR and beta 2 microglobulin expression. Expression was most prominent in medullary carcinoma, followed by atypical medullary carcinoma and invasive duct carcinoma with and without lymphocytic infiltrates. The mean intensity and percentage of HLA-DR tumour immunostaining were significantly higher in medullary carcinoma than in the other three tumour groups, as was the mean intensity of beta 2 microglobulin immunostaining. Mean percentage of beta 2 microglobulin immunostaining was significantly higher in medullary carcinoma than in invasive duct carcinoma without lymphocytic infiltrates, and showed a trend to increase from invasive duct carcinoma with lymphocytic infiltrates to atypical medullary carcinoma and medullary carcinoma.

CONCLUSIONS

Medullary carcinoma and atypical medullary carcinoma of the breast differ in their expression of HLA-DR and beta 2 microglobulin. The relatively favourable prognosis of medullary carcinoma of the breast may be related to effective tumour antigen presentation to the immune system through MHC-I and MHC-II expression. Immunotherapy aimed at MHC-I and MHC-II induction might have a beneficial effect in breast cancer.

Inflammatory infiltrate in invasive lobular and ductal carcinoma of the breast

The significance of inflammation in carcinoma of the breast is controversial. Little attention has been paid to different patterns of inflammation or inflammation associated with different histological types of carcinoma. We have looked at the pattern of inflammation in 123 invasive mammary carcinomas (including 46 lobular), and characterised the inflammatory cells with immunohistochemistry in 21. We found different patterns of inflammation in ductal and lobular carcinoma. Diffuse inflammation was seen more in ductal carcinoma, particularly of high grade, and was predominantly composed of macrophages and T cells. It was associated with necrosis, but the correlation was weak, suggesting that other factors are important. Perilobular inflammation was seen most frequently in lobular and high-grade ductal carcinomas, particularly at the tumour edge. Perivascular inflammation was also largely at the tumour edge, but was not more common in any tumour type. In contrast to the diffuse inflammation, the perivascular and perilobular inflammation was composed of T and B cells. Normal lobules at the tumour edge showed consistent expression of HLA-DR, whereas lobules away from the tumour were negative. A combination of perilobular and perivascular inflammation composed of B and T cells with epithelial expression of HLA-DR mimicking lymphocytic lobulitis was seen more frequently in lobular than ductal carcinoma.

Prognostic significance of T-cell infiltrates, expression of beta 2-microglobulin and HLA-DR antigens in breast carcinoma

In this study immunohistological staining was used to assess the presence of T-cell infiltrates and the expression of beta 2-microglobulin (beta 2-m) and HLA-DR antigens on tumor cells of 75 ductal invasive carcinomas. The results were compared with the morphometric prognostic index (MPI) that seems to be the most accurate prognostic predictor. The extent of T-cell infiltrates differed widely between tumors, but statistically significant correlation was found only with the lymph node status, namely, tumors with a high degree of infiltration had predominantly negative lymph nodes and vice versa (p < 0.05). Only 19 (25.3%) out of 75 carcinomas were beta 2-m+, 34 cases (45.3%) showed heterogeneous staining pattern and 22 tumors (29.3%) were completely negative. We could not find any significant correlation between beta 2-m expression and MPI or T-cell content. While normal breast epithelium was always HLA-DR negative, tumor cells displayed positivity in 25 cases (33.3%), 5 tumors (6.7%) were completely positive and 20 tumors (26.7%) displayed only focal expression of class II antigens. This expression did not correlate with any single prognostic parameter, nor with MPI. The results suggest that T-cell infiltrates and the expression of histocompatibility antigens can not be accepted as prognostic indicators in breast carcinoma.

Patho- and immunobiology of malignant mesothelioma: characterisation of tumour infiltrating leucocytes and cytokine production in a murine model

Malignant mesothelioma (MM) is an aggressive, uniformly fatal serosal tumour, usually associated with asbestos exposure, for which there currently is no effective treatment. In order to gain insight into the mechanism(s) whereby MM might escape immune surveillance, a murine model for MM was used (a) to characterise the tumour-infiltrating lymphocytes (TIL) and macrophages (TIM) phenotypically, (b) to examine systemic immune recognition of MM, and (c) to examine the possible influence of tumour-derived cytokines on systemic and local pathobiological manifestations of MM. A profound down-regulation of lymphocyte surface markers, known to be involved in T cell activation, was found in TIL. Likewise, although TIM were present in large numbers, their expression of MHC class II antigen and integrins was weak or absent, suggestive of altered functional activity. Significant amounts of cytokines, in particular transforming growth factor beta, interleukin-6 (IL-6), IL-1 and tumour necrosis factor were produced during the course of MM tumour development-directly by the MM cells and/or indirectly in response to tumour growth. These factors may contribute both to derangement of antitumour effector mechanisms and to the clinical and pathological manifestations of the disease.

Anti-tumor antibody produced by human tumor-infiltrating and peripheral blood B lymphocytes

Cell suspensions from 69 human tumor biopsies and malignant effusions depleted of infiltrating T cells were incubated for 10-14 days with mitomycin-C-treated cells of the transformed T cell line MOT as feeder cells. B lymphocytes proliferated and differentiated as indicated by immunoglobulin (Ig) secretion in the culture supernatants (B cell expansion). Ig was present in culture supernatants of tumor cell suspensions incubated without MOT feeder cells (non-expanded cells), but the addition of MOT feeder cells to these cultures invariably resulted in a significant increase in Ig concentration. While IgG, IgA, and IgM isotypes were all detected in supernatants of both expanded- and non-expanded tumor cell suspensions, the increase in total Ig induced by MOT feeder cells was mainly due to an increase in IgG. Peripheral blood B lymphocytes (PBBL) from 15 cancer patients and 4 healthy individuals were also successfully expanded by the same method. In these it was shown that IgA was the predominant Ig isotype. Using a modified enzyme-linked immunosorbent assay, IgG of 25/36 expansions from tumor cell suspensions showed reactivity with autologous tumor targets, and that from 10/13 expansions reacted with allogeneic tumor targets of the same histological diagnosis. No reactivity was found against tumor targets of different histology. IgG of 4/10 expansions of PBBL from cancer patients showed reactivity with allogeneic tumor targets of the same histology, while no reactivity was demonstrated against tumor targets of different histology. IgG of expanded PBBL from healthy individuals showed no reactivity against tumor targets. This method allows detailed study of the specific humoral antitumor immune response of intratumoral and peripheral blood B lymphocytes in cancer.

Variable natural killer function of tumour-infiltrating lymphocytes from breast carcinomas

Samples were obtained from 36 breast cancer patients: 24 tissue samples from carcinomas, six samples from non-cancerous breast tissue and 22 samples of peripheral blood (PB). Natural killer (NK) activity was tested against the classical target K-562 and the breast carcinoma cell line T-47D, using a microcytotoxicity assay measuring inhibition of uptake of 3H-thymidine by target cells. The active effector cells against both target cell types were identified as CD-56-positive large granular lymphocytes. PB lymphocytes from breast cancer patients showed normal NK activity against both K-562 (mean inhibition: 75.4%, controls: 78.1%) and T-47D (mean inhibition: 77.6%, controls: 78.0%). Tumour-infiltrating lymphocytes (TIL) from 24 breast carcinomas showed considerable variation in NK activity against K-562: only two cases (8%) had no activity (less than or equal to 5% inhibition), 15 cases (63%) had moderate activity (15-48% inhibition), and seven cases (29%) showed full NK activity (defined as greater than or equal to 50% inhibition). TIL from three carcinomas were also tested against T-47D and gave 21-46% inhibition. The NK activity of TIL declined with time in culture with one notable exception where there was full NK activity after seven days in culture. NK activity of TIL showed significant positive correlation with increasing degree of lymphocytic infiltration of the tumour, and correlated also with PB NK activity. No correlation was apparent with stage of disease. The NK activity was usually lower in the TIL than the PB sample when tested in parallel. This difference was probably caused by experimental conditions as well as different relative numbers of natural killer cells. In six cases tested, infiltrating lymphocytes from carcinoma and normal tissue from the same breast were found to have similar NK activities. We conclude that the non-specific cytotoxic activity of TIL from breast carcinomas covers the whole range from complete lack of function to full capacity comparable with NK activity of PB lymphocytes. The level of activity was moderately correlated with the degree of lymphoid infiltration but was not related to stage of disease. Differences in functional capacity of TIL may be of importance in predicting possible benefits from immunomodulating therapy.

Assessment of tumour-infiltrating lymphocytes, regional lymph node lymphocytes and peripheral blood lymphocytes and their reaction to interferon-gamma in patients with renal carcinoma

The immunological distribution of tumour-infiltrating lymphocytes (TIL), regional lymph node lymphocytes (RLNL) and peripheral blood lymphocytes (PBL) was evaluated by means of immunohistochemical staining using monoclonal antibodies of each subset of lymphocytes (stored in frozen sections) in a series of 22 patients with renal carcinoma. The immunological effect of IFN (interferon)-gamma on these immunocompetent cells was also investigated. The effect of IFN-gamma on TIL was an increase in CD3 (pan-T cells), especially an increase in CD8 (cytotoxic/suppressor-T cells). When examining these cells according to stage and grade, a marked increase in CD3 was found in low stage and low grade patients. With regard to RLNL, there was a tendency towards a decrease in CD3 and an increase in CD20 (B-cells) following the administration of IFN-gamma. No specific effect on stage and grade was observed apart from a reduction in T cell subset ratios in high grade patients. With regard to PBL, no specific trend was noted except for an increase in CD16 (NK cells) when IFN-gamma was administered.

Study of the relationship between immunohistologically demonstrated lymphocytes infiltrating human breast carcinomas and patients' survival

Eighty-five breast carcinomas were immunostained for CD3-, CD4-, CD8-, CD16-, CD22-, CD38- and CD57-positive lymphocyte subpopulations. The results were related to follow-up data (median follow-up 46 months) of 74 patients regarding overall survival and 73 patients in respect to disease-free survival. Whereas the number of axillary lymph node metastases (P less than 0.01) and the hormone receptor status (P less than 0.01) resulted in significantly different survival curves for overall survival, not one of the lymphocyte subset infiltrats correlated significantly which overall survival. For disease-free survival, pT stage (P less than 0.01) and nodal (P less than 0.01) and hormone receptor status (P less than 0.05) proved to be prognostically important. However, disease-free survival was not influenced by the infiltration of any lymphocyte subset.

Flow cytometric analysis of tumour infiltrating lymphocytes in breast cancer

In 31 patients with carcinoma of the breast the phenotype and activation status of tumour infiltrating lymphocytes (TILs) was analysed by flow cytometry. The predominant cells, in all patients, were T lymphocytes and in the majority of cases CD8+ (cytotoxic/suppressor) T lymphocytes were present in greater numbers than CD4+ (helper) T lymphocytes. There was no relationship between the degree of lymphocytic infiltration and either tumour stage or grade but there appeared to be an inverse correlation with the levels of oestrogen receptor (ER) in the tumour (P less than 0.01). Both populations of T cells had significantly higher numbers of cells carrying HLA DR (class II major histocompatibility antigen) than the equivalent populations in peripheral blood from the same patient group (P less than 0.001). The transferrin receptor was found on similar numbers of CD8+ T cells in peripheral blood and among the tumour infiltrating lymphocytes while more of the CD4+ T cells infiltrating the tumour were found to carry this receptor (P = 0.034). The Tac (CD 25) antigen was also on similar numbers of CD8+ T cells from both peripheral blood and the tumour but was on fewer of the CD4+ T cells in the tumour with respect to peripheral blood (P = 0.029). In both TILs and blood lymphocytes, the Tac antigen was consistently present on greater numbers of CD4+ T lymphocytes than on the CD8+ T lymphocytes (P less than 0.001) and as this is a component of the interleukin 2 (IL-2) receptor this may be of relevance to the use of IL-2 in TIL cancer therapy.

Lacking prognostic significance of beta 2-microglobulin, MHC class I and class II antigen expression in breast carcinomas

To evaluate the impact of MHC antigen expression on the survival of patients with cancer, 77 human breast carcinomas were investigated for the expression of beta 2-microglobulin (beta 2m), HLA-A,B,C and HLA-DR. Thirty-one benign breast tumours were stained for comparison. The results for the carcinomas were related to the survival data of the cancer patients. The expression of beta 2m, HLA-A,B,C and HLA-DR was significantly lower in malignant tumours compared to the benign lesions. Whereas all benign tumours were positive for beta 2m and HLA-A,B,C and 28/31 positive for HLA-DR the following positivity rates were found in carcinomas: 74/77 for beta 2m, 57/77 for HLA-A,B,C and 10/77 for HLA-DR. The follow-up (median 45 months) of 66 cancer patients for overall survival and of 65 patients for disease-free survival revealed no influence of beta 2m, HLA-A,B,C or HLA-DR expression on the prognosis of this cancer. In conclusion, experimental data indicating the importance of MHC antigens in anti-tumour responses are not confirmed by the analysis of cancer patient survival data.

Phenotypic characteristics of tumour-infiltrating lymphocytes in human oesophageal cancer tissues defined by quantitative two-colour analysis with flow-cytometry

Phenotypic subpopulations of tumour-infiltrating lymphocytes (TIL) separated from human oesophageal cancer tissues were defined by quantitative two-colour analysis with flow-cytometry (FACScan), and their characteristics were investigated by comparison with peripheral blood lymphocytes (PBL) and intra-oesophageal lymphocytes from noncancerous tissue (IEL) as the controls. Fifteen patients (13 males and 2 females) with squamous cell carcinoma of the oesophagus were entered into the study. Lymphocytes were analyzed by FACScan and the frequencies of the subpopulations were determined using monoclonal antibodies for surface markers. Single colour analysis revealed a predominance of T cells among TIL and a significant reduction of natural killer (NK) cells compared with the controls. Two-colour analysis showed that CD4+ Leu8- (helper T cells) and CD8+ CD11b- (cytotoxic T cells) were significantly increased among TIL when compared with the controls. This significant increase of both helper and cytotoxic T cells, which are indispensable components of cellular immunity, strongly implies that TIL are performing a role in the expression of antigen-specific cellular immunity against the tumours. This is the first report of a phenotypic study of human oesophageal cancer that clearly indicates the significance of the TIL and suggests their potential for use as a source of adoptive immunotherapy.

Histocompatibility antigen expression in pulmonary carcinomas as indication of differentiation and of special subtypes

In 70 human carcinomas of the lung the expression of histocompatibility antigens (HLA) was investigated by using monoclonal antibodies in frozen sections. The immunmoreactive tumor volume was determined morphometrically. The tumor types showed a different pattern of HLA expressions. In squamous cell carcinomas (SQC) and small cell carcinomas (SCC) the HLA-A,B,C expression varied in a great range from 0% to 100% of positive tumor volume. For the most part, HLA-DR was not demonstrable. In adenocarcinomas (AC) and large cell carcinomas two different populations were observed. One showed a pattern of HLA expression as seen in SQC. Electron microscopically these AC (type 1) (AC/1) were characterized by intracytoplasmic mucin granules indicating a phenotypical relationship to goblet cells. The other--nearly 50% of adenocarcinomas and one third of large cell carcinomas--expressed both HLA antigens homogeneously in the total tumor volume. Electron microscopically the characteristics of type II pneumocytes and Clara cells were seen in tumor cells of these AC (type II) (AC/II), consisting in lamellar bodies and apically located electron-dense granules. In SQC and AC/I a significant correlation was found between grades of differentiation and mitotic activity on the one side, and expression of HLA-A,B,C on the otrher. The loss of HLA-A,B,C expression seemed to be an indication of a lower grade of differentiation; the smalles expression of HLA-A,B,C occurred in SCC.

Immunohistologic study of mononuclear cell infiltrates in oral squamous cell carcinomas

Intensity of mononuclear cell infiltrates in 50 oral cancer tissues was evaluated by immunohistochemical stainings. The intensity of the infiltrates was graded into four degrees from marked ( ) to absent (-); and the degree of each infiltrated lymphocyte subpopulation including Leu-3a3b/Leu-2a ratio was matched against clinical and histopathologic features. The vast majority of the infiltrated lymphocytes had antigens which were reactive with anti-T cell antibodies. In T cell subsets, Leu-3a3b+ cells infiltrated clearly (grade ++ or ) in 44 cases, and infiltration greater than grade ++ of Leu-2a+ cells was found in nearly half of the cases (26 of 50). In contrast, B cells (Leu-14+ cells) were obviously detectable in only a few cases, and moderate or marked infiltration of the natural killer (NK) population (Leu-11b+ cells) was not observed. Regarding correlation of T cell infiltrates with clinicopathologic features of the tumors, the degrees of Leu-4+ cell and Leu-2a+ cell infiltration became weak with advancing T stage. Leu-2a+ cells also infiltrated weakly into diffusely invading tumors. Out of 28 cases with no metastasis, 22 cases (78.6%) showed grade ++ approximately of Leu-2a+ cells, and only 4 (18.2%) of 22 cases with lymph node metastasis were clearly positive for Leu-2a+ cells (p less than 0.001). However, Leu-3a3b+ cell infiltration was only slightly related to T stage, metastasis, and to mode of invasion. Therefore, the Leu-3a3b/Leu-2a ratio increased significantly in advanced (T3 + T4) tumors, metastasized cases, or diffuse invasion type.

Quantitative immunohistochemical analysis of mononuclear infiltrates in breast carcinomas--correlation with tumour differentiation

Inflammatory infiltrates were analysed in tissue sections of 76 breast carcinomas by counting the percentage of macrophages, IgA+ and IgG+ plasma cells, T cells with their subpopulations, and natural killer cells, and by measuring postcapillary venules (PCVs, found in 12 cases) within the infiltrates. These parameters were correlated with nuclear grade and biochemically determined hormone receptor status, known markers of tumour differentiation. A direct correlation was found between the extent of inflammation and nuclear grade (P less than 0.0001), and an inverse correlation between inflammation and oestrogen receptor (OR) positivity (P less than 0.05) as well as inflammation and progesterone receptor (PR) positivity (P less than 0.05). The percentage of the OKT8+ suppressor/cytotoxic T cells increased when the inflammation expanded from scanty to moderate (P less than 0.02). The diameter of the PCVs also increased with increasing inflammatory infiltrate (P less than 0.02). In addition, a direct correlation exists between the diameter of the PCVs and both the percentage of the OKT8+ T cells (P less than 0.04) and the Leu-7+ natural killer cells (P less than 0.03).

Sparse distribution of gamma/delta T lymphocytes around human epithelial tumors predominantly infiltrated by primed/memory T cells

Evidence from the mouse system has suggested that T lymphocytes accumulating in non-lymphoid tissue, in particular epithelia, may preferentially express the T cell receptor (TCR) gamma delta. In this study, we characterize the T cell receptor alpha beta or gamma delta phenotype of lymphocytes infiltrating human tumors of epithelial origin using monoclonal antibodies (mAb) for immunohistology and flow cytometry on cells extracted by enzyme digestion. This report shows that the majority of CD3+ tumor-infiltrating lymphocytes are TCR alpha beta+ but a small percentage of TCR gamma delta can be clearly defined scattered throughout the tumor tissue with apparently no microanatomical selection. So far there has been little evidence for an accumulation of activated T cells in human tumor tissues as defined by mAb against molecules appearing transiently during the acute phase of activation. Now mAb are available that can identify primed or memory T cells such as mAb UCHL-1 recognizing the CD45RO antigen. Here we show that CD3+ tumor-infiltrating lymphocytes have a statistically significant accumulation of primed T cells, as compared to the autologous peripheral blood lymphocytes, suggesting their immune stimulation by tumor cells.

Correlation of HLA-D/Ii antigen expression in breast carcinoma with local lymphohistiocytic infiltration reveals considerable dysregulation in a subset of tumors

Non-neoplastic mammary glands and 203 carcinomas of the breast were examined immunohistochemically for expression of HLA-DR, -DP, and -DQ molecules and the HLA-D-associated invariant chain (Ii). According to the reaction of normal breast epithelium in the course of chronic inflammation, these antigens were found to be induced in 120 carcinomas. In 106 of these the order was Ii greater than or equal to HLA-DR greater than or equal to HLA-DP greater than or equal to HLA-DQ. The extent of induction of these sequentially expressed antigens correlated with the density of local lymphohistiocytic infiltration (Ii: p = 0.003; HLA-DR: p = 0.0005; HLA-DP: p = 0.0000005; HLA-DQ: p = 0.01). Therefore, Ii/HLA-D antigen expression of carcinoma cells in local association with inflammation was regarded as an adequate reaction. The presence of these antigens in the absence of inflammation was regarded as "inadequate hyper-expression", and was found in 14 cases involving Ii, in 8 involving HLA-DR, and in 1 case each involving -DP and -DQ molecules. In contrast, 20 cases expressed minimal/no Ii despite heavy inflammatory infiltration. This "inadequate hypo-expression" was also found in 25 cases involving HLA-DR, in 30 involving -DP and in 40 involving -DQ determinants. Combining the 2 variants showed that at least 54 cases (26.6%) were characterized as being dysregulated. "Adequate vs. inadequate Ii/HLA-D antigen expression" did not correlate with tumor grading and might therefore be an independent parameter.

What's new in the local immune response in cancer?

Malignant tumors in humans are commonly associated with an inflammatory infiltrate. The mechanisms that account for the accumulation of T-lymphocytes and macrophages--these cells comprise the major components of tumor infiltrates--in the vicinity of a growing tumor are not fully understood. Tumor specific and immunogenic antigens could not be demonstrated in most solid tumors of humans, in contrast to several experimental tumor models. Thus it is not proven in human malignancies that neoantigens expressed on malignant cells are the signal which initiates an inflammatory response that, immunohistologically, is comparable to mononuclear infiltrates present in allograft rejection. A variety of nonspecific factors including lymphokines released by tumor cells may also account for the accumulation of inflammatory cells at the tumor site. The difficulties to evaluate the functional role of the "local immune response" for tumor and host are even greater. Most tumors progress in the presence of mononuclear infiltrates. Do they progress in spite of or because of the action of the local immune response? Clinical, immunopathological, and experimental data suggest that both is right, and that at least four distinct properties of tumor-associated immune reactions exist: Regression, Selection, Modulation and Progression. These distinct properties will be discussed below, using mainly the malignant melanoma of the skin as a model for a malignant tumor in humans.

In situ hybridisation and S1 mapping show that the presence of infiltrating plasma cells is associated with poor prognosis in breast cancer

In order to identify potential markers of prognosis in breast cancer, representative cDNA libraries were constructed using RNA isolated from primary breast tumour tissue associated with good and poor prognosis. Cross-screening of these libraries repeatedly identified cloned mRNA species associated with the immune system, in particular B-cells, in libraries derived from tumours of poor prognosis. We have used one of these a kappa IV light chain cDNA probe, in two complementary studies to investigate the relationship between immunoglobin gene expression and prognosis. The results obtained using a combination of S1 mapping, RNA blotting and in situ hybridisation demonstrate that the presence of plasma cells, as defined by infiltrating cells which express high levels of immunoglobulin kappa-chain mRNA, is associated with a poor prognosis.

HLA class II sublocus expression in benign and malignant breast epithelium

Using immunohistochemistry and a panel of five monoclonal antibodies, the epithelial expression of HLA class II sublocus products by benign and malignant breast has been studied. The magnitude of the stromal mononuclear inflammatory cell infiltrate was assessed. There was expression of HLA class II by 75 per cent of epithelial cells in the benign tissues, with little variation in intensity and between antibodies. There was coordinate expression of DR and DQW1. Epithelial expression by carcinomas was more complex and variable. Most (61 per cent) carcinomas exhibited variable loss of epithelial expression of class II products, as detected by three antibodies recognizing epitopes on DP, DQ, and DR together. Thirteen (28 per cent) carcinomas were completely negative or had very occasional positive cells. The extent of this loss was unrelated to the magnitude of the inflammatory infiltrate and axillary lymph node status. No well-differentiated carcinomas exhibited complete loss. Furthermore, non-coordinate expression of DR and DQW1 was present in 8 out of 40 carcinomas, with the proportion of DQW1 positive epithelium always being less than that of DR. Carcinomas exhibiting non-coordinate expression were never well differentiated; there was no relationship with the extent of the inflammatory infiltrate. This is the first study to detail HLA class II expression in breast, and our results suggest that alterations in expression of these products may modify or reflect tumour behaviour.

Inflammatory cell infiltrates in human melanoma at different stages of tumor progression

Progression of human melanoma is associated with changes in antigenic phenotypes of tumor cells. To establish whether inflammatory infiltrates in progressing melanoma also change, we studied 146 cutaneous melanomas at different stages of progression. Monoclonal antibodies (MAbs) against lymphocyte and macrophage subpopulations, interleukin-2 receptor (IL-2 R), immune interferon (IFN-gamma), and the IFN-gamma-inducible, progression-associated melanoma antigens HLA-DR and gp89 were applied in situ. During the course of melanoma progression, decreased amounts of peritumoral T cells, IL-2 R-expressing lymphocytes and dermal T6+ dendritic cells were found, while increased numbers of intratumoral T cells, inflammatory (27E10+) and mature (25F9+) macrophages were associated with local progression of primary melanomas. In metastases, most infiltrate components except 25F9+ macrophages were rare. Positive correlations were observed between: (1) dermal T6+ cells and IL-2 R+ lymphocytes, and (2) presence of IFN-gamma in the infiltrate and HLA-DR and gp89 antigens on tumor cells. In all stages, HLA-DR expression on tumor cells was correlated with: (1) a shift towards T8+ lymphocytes in the infiltrates and (2) a loss of IL-2 R expression. Our data suggest mutual influences between melanoma cells and mononuclear cell infiltrates in situ.

P53 expression in breast cancer

Immunohistochemical evaluation of 200 primary breast cancers with the anti-p53 mouse monoclonal antibody (MAb) PAb421 showed positivity in nuclei of malignant cells in 31 cases (15.5%). PAb421+ cases were significantly more frequently epidermal growth factor receptor (EGF-R)-positive (67.7%; p less than 0.001) and estrogen receptor (ER)-negative (73.3%; p less than 0.001); they displayed surface histocompatibility class-1 (80.6%; p less than 0.01) and 11 (74.2%; p less than 0.05) antigens. Low values for progesterone receptor (mean 67.20 +/- 25.2 fmol/mg; p less than 0.05) and a high number of cells positive for the proliferation-associated antigen Ki-67 (log mean 6.88 +/- 0.33; p less than 0.01) were found in PAb421+ tumors as well as a high number of grade-3 infiltrating duct carcinomas (70%; p = 0.01). Of the 200 cases of mammary carcinoma, 88 were further analyzed using another human specific anti-p53 MAb PAb1801, and 40 (45.5%) were found positive. This MAb stained all the PAb421+ cases and was significantly associated with negative ER status (39.5%; p less than 0.05) and high Ki-67 scores (log mean 6.93 +/- 0.24; p = 0.001). Analysis of PAb1801+/Pab421- cases for HLA antigens, EGF-R and ER showed a phenotype similar to that of the p53-ve/ER+ carcinomas, except for the high Ki-67 score. No differences in age of the patient, number of involved nodes, tumor size, ploidy or labelling index scores were evident between p53+ and carcinomas. We concluded that p53 in mammary carcinomas is associated with ER-negative, growth factor receptor-positive, high-grade tumors, and is a promising new parameter to evaluate the cellular biology and prognosis of breast cancer.

Characterization and frequency distribution of lymphoreticular infiltrates in axillary lymph node metastases of invasive ductal carcinoma of the breast

One hundred and seventy-five axillary lymph nodes containing metastatic deposits from 46 invasive ductal carcinomas of the breast were evaluated histologically and immunohistologically. The study yielded the following results: (1) tumor-infiltrating lymphoreticular cells preferentially accumulated in the stromal bands; the tumor foci generally showed a considerably lower degree of infiltration; (2) in most cases, monocytes/macrophages (Mono 1+) represented the overwhelming majority of tumor-infiltrating cells; (3) next in frequency were T-lymphocytes (Leu-1+), especially CD4+ lymphocytes (Leu-3a+), while CD8+ lymphocytes (Leu-2a+) mostly occurred only in moderate numbers; (4) B-lymphocytes (To15+), plasma cells, natural killer cells (Leu-7+), tissue mast cells, and T-accessory reticulum cells (OKT 6+) were observed mostly in low or very low numbers, while eosinophils were nearly absent and B-accessory reticulum cells (Ki-M4+) were totally absent from the lymphoreticular infiltrates. Definite conclusions regarding the functional properties of the tumor-infiltrating cells cannot be drawn from an immunohistologic analysis in situ alone, but the preferred localization of most tumor-infiltrating cells in the stroma does not support an intensive interaction between the host defenses and the metastatic tumor.

HLA-DR antigens on differentiating human mammary gland epithelium and breast tumours

The staining pattern of a monoclonal antibody directed to the monomorphic determinant of HLA-DR antigens was examined on sections of human mammary gland tissues at various stages of differentiation as well as on 50 benign and 72 malignant breast lesions. Normal resting breast epithelium lacked HLA-DR, whereas late-pregnant and lactating epithelia expressed high levels of HLA-DR antigens, followed by a decline in the post-weaning regression period. Most benign breast lesions revealed heterogeneous staining ranging from very few up to 20-25% positive epithelial Greater variability was observed among carcinomas, where a small group (approximately 7%) of cases showing 40-95% positive tumour cells was found, in addition to negative tumours and those with the minority of HLA-DR expressing carcinoma cells. The density of the leukocytic infiltrate was higher in carcinomas than in either normal breast tissue or benign lesions, the HLA-DR phenotype of the mononuclear infiltrating cells lacking any obvious correlation with the HLA-DR status of the epithelial component. Immunoblotting analyses of whole-tissue lysates separated by SDS-PAGE confirmed the immunohistochemical data and demonstrated the reactivity with only one protein band predicted for HLA-DR alpha-chain. The combination of immunohistochemistry and autoradiography on sections of human reduction mammoplasty organoids cultured in collagen gels and labelled with tritiated thymidine revealed a lack of HLA-DR expression on proliferating breast epithelial cells suggesting factors other than cell kinetics must be responsible for induction of HLA-DR antigens seen in pregnant and lactating breast epithelium and some tumours.

Immunohistochemical analysis of HLA antigens and mononuclear infiltrates of benign and malignant breast

Using immunohistochemistry, the epithelial expression of HLA Class I and II antigens (and beta 2 microglobulin) was compared in benign and malignant breast, and the stromal lympho-histiocytic infiltrate of these tissues quantified. The findings were compared with certain characteristics of the carcinomas. In contrast to other studies, malignancy was found to be associated with a far greater infiltrate of both lymphocytes and macrophages. In carcinomas, lymphocyte but not macrophage numbers showed a positive correlation with epithelial HLA ABC and HLA DR expression. This was particularly striking for T lymphocytes, and especially for the T4 subset. The histological grade of carcinoma is closely related to the degree of HLA ABC and beta 2 microglobulin expression, but no such relationship was found for HLA DR. There were greater numbers of mononuclear cells in the poorer differentiated tumours compared with other grades. Those carcinomas with evidence of lymph node metastasis contained greater numbers of macrophages identified by the antibody Y1/82A, but none of the other parameters studied was found to be associated with local lymph node status. The use of a large panel of monoclonal antibodies against various cellular subtypes has allowed a more detailed analysis of the interaction between breast epithelium and the host response.

Immunohistological analysis of lymphocyte subpopulations infiltrating breast carcinomas and benign lesions

We characterized different subpopulations of infiltrating mononuclear cells using 8 monoclonal antibodies (MAbs) on serial cryosections of breast tissue from 85 cancer patients and 32 samples of benign lesions, and the ABC technique. In general, lymphocytes were found more frequently and more abundantly in cancerous lesions. The infiltrates consisted mainly of T-cells in close contact with malignant cell-nests. T-helper/inducer cells clearly predominated over T-suppressor/cytotoxic cells in neoplastic tissues, whereas in benign tissues the T-helper/suppressor ratios seemed to be well balanced. While a few MAb Leu-7 (HNK-I)-reactive NK cells were found in the stroma of the breast tumors, none could be identified in the noncancerous lesions. The correlation of these data with histology and tumor stage of patients has been evaluated by a quantitative approach using planimetry in an interactive registration system.

An immunohistologic study of the distribution and status of activation of head and neck tumor infiltrating leukocytes

We examined tumor infiltrating leukocytes (TIL) in frozen sections of 28 biopsies from squamous cell carcinomas of the head and neck (SCCHN). In so doing, we used monoclonal antibodies (MoAb) directed against various leukocyte antigens. As defined by HLe-1+ cells, leukocyte infiltration was present in all biopsies. The amount of HLe-1+ cells was more often greater in stage III than in stage IV lesions. Most of the TIL were identified as CD5+ T-lymphocytes. In contrast, CD19+ B-cells were sparse in most biopsies. CD14+ monocytes/macrophages were found in only a few specimens. The relative proportion of CD4+ T-helper cells was higher than or at least equal to CD8+ suppressor/cytotoxic cells in all samples tested. Interleukin-2 (IL-2) receptor+ lymphocytes were evident in 13 of 22 biopsies stained for CD25 reactivity, and were more often observed in stage III than in stage IV tumors. All biopsies from recurrent tumors had no detectable IL-2 receptor+ cells. Our findings provide evidence for a positive correlation between a greater amount of TIL in earlier stages of SCCHN. The presence of IL-2+ lymphocytes suggests that SCCHN may be capable of activating resting lymphocytes for further IL-2-induced proliferation.

Antigenic phenotype of the lymphocytic component of medullary carcinoma of the breast

Medullary carcinoma of the breast, which is usually associated with a dense lymphocytic infiltrate, carries a better prognosis than do most other histologic subtypes of breast carcinoma. We studied cryostat-cut fresh frozen sections from 12 patients with medullary carcinoma and, as controls, nine patients with infiltrating ductal carcinoma in order to determine and compare the antigenic phenotype of the lymphocytic components of these tumors. We used a large panel of monoclonal antibodies and polyclonal antisera for T-cells (Leu-1, Leu-2a, Leu-3a, Leu-9, T-3, T-6, T-10, T-11, and TQ-1), pre-B and B-cells (BA-1, B-1, B-2, B-4, and J5), NK cells (Leu-7 and Leu-11b), and cell activation associated antigens (T-9, HLA-Dr, and Tac). The most commonly encountered antigens on the lymphocytic components of both medullary carcinoma and infiltrating ductal carcinoma were: T-3, T-11, Leu-1, Leu-2a, Leu-3a, and Leu-9. There was little staining for NK-, pre-B-, or B-cell associated antigens in either type of carcinoma. However, the lymphocytes in the control cases tended to express HLA-Dr and T-10 more often than did the lymphocytes in the cases of medullary breast carcinoma. Our data indicate that: the antigenic phenotypes of the lymphocytic infiltrates of medullary carcinoma and those of infiltrating ductal carcinoma of the breast are essentially similar; and the lymphocytes in these carcinomas are composed predominantly of peripheral T-lymphocytes. We therefore conclude that the favorable biologic behavior of medullary carcinoma of the breast cannot readily be explained by the immunophenotype of its lymphocytic component.

Lymphocyte phenotypes at tumor margins in patients with head and neck cancer

Lymphocyte phenotypes were identified by monoclonal antibodies and avidin-biotin peroxidase reagents and enumerated in tumor tissue removed from 26 patients with head and neck cancer. T lymphocytes (T11) were the predominate phenotype at the tumor margin, with twice as many helper/inducer (T4) as suppressor/cytotoxic (T8) lymphocytes. Patients with Stage II and III carcinoma of the glottis, tongue, and hypopharynx had significantly increased numbers of all T lymphocyte phenotypes when compared to patients with Stage IV disease, thus achieving statistical significance for the T11 and T8 phenotypes. All patients were followed for 2.5 years; those patients who remained free of malignant disease had an increased number of all T lymphocyte phenotypes compared to patients with recurrent malignancy, but this did not achieve statistical significance. Thus, increased numbers of T11 positive lymphocytes of both the T4 and T8 subsets in the tissue at the margins of head and neck tumors were associated with a more favorable prognosis. These results support the concept of an immunologic reaction at the tumor margin, which may be limiting the growth and spread of tumor.

Transformation of blood monocytes to giant cells in vitro from patients with breast cancer

Monocytes from patients with breast cancer and from control subjects were cultured under agarose for 6 days. Giant cell formation occurred in 32 out of the 36 patients with breast cancer (89 per cent). In contrast giant cell formation was only observed in two of the control subjects (6 per cent). Menstruation and menopause had no effect on giant cell formation. Furthermore, under the experimental conditions of this study, it seems unlikely that serum factors, lymphokines or phagocytic stimulators induced giant cell formation. The results therefore, suggest that giant cell formation may be initiated by viruses already present in the monocytes from patients with breast cancer. Further studies are required to confirm this hypothesis and to elucidate the significance of giant cell formation in the pathogenesis of breast cancer.

Immunohistochemical study on the distribution and significance of mononuclear cells in human breast carcinoma

Lymphocyte subsets in the tumor nests of breast carcinoma were immunohistochemically investigated and a quantitative analysis was added. The majority of cases showed predominance of T cell and suppressor T cell (T8). A decrease in number of lymphocyte subsets and the helper T (T4)/T8 ratio in the stroma of tumor nests correlated well with the progression of clinical stage and the presence of metastasis. This correlation could not be found in the peripheral region of the tumor nests. Macrophages and NK cells were infrequently observed only in the peripheral region of ductal carcinoma. T cell infiltration was prominent in medullary carcinoma with lymphocyte infiltration (MC), and macrophages, NK cells, and T zone histiocytes were frequently encountered. For the purpose of knowing the activity of T cells, IL-2 receptor (Tac) and transferrin receptor were examined immunohistochemically. The fact that a few activated T cells were found only in the peripheral region of tumor nest suggested the local immune response in ductal carcinoma not to be so active as to reject the tumor cells. Since numerous activated T cells were recognized in the tumor nests of MC, this type of breast carcinoma was thought to have a higher immune reactivity. There was little evidence indicating NK cells to play a role for natural cytotoxicity in breast carcinoma.

Inflammatory infiltrates of experimental mammary cancers

The purpose of this review was to summarize observations on the type and function of inflammatory infiltrates of mouse mammary tumors and to speculate on the underlying mechanisms and the significance of infiltrates to mammary tumor biology. Although the major conclusion is that much more work is needed, certain themes seem to be emerging. The number of infiltrating cells can be very high but is unrelated to biological behavior of the tumors. What seems to be important is the relative contributions of inflammatory cell subsets. In the case of T-cell subsets and NK cells, the infiltrates from tumors of long-term cell lines so far seem uninformative. The general characteristics are similar to those of infiltrates from rapidly proliferating, normal mammary tissues. These characteristics do not correlate with diverse biological behavior or malignant potential. A more informative model appears to be one in which the development of tumors from preneoplastic tissue can be observed. Here our attention is currently focused on NK cells. By contrast, the correlation between activated TAM and metastatic behavior suggests that our transplantable MMT lines may be biologically relevant in the study of infiltrating macrophages. We are especially interested in the role of TAM in the generation of tumor cell variability. Overall, our data indicate that the host infiltrate is another manifestation of both inter- and intra-tumor heterogeneity and, as such, is not simply a response to, but, rather, a part of the tumor ecosystem. Unraveling the cellular and molecular mechanisms that govern the inflammatory cell component of tumors should provide insight into the types of cellular interactions that result in tumor development and progression.

Separation, phenotyping and limiting dilution analysis of T-lymphocytes infiltrating human solid tumors

Tumor-infiltrating lymphocytes (TIL) were obtained by a combination of mechanical release and enzymatic disaggregation from 35 human solid tumors. The number of lymphocytes in TIL-enriched suspensions varied from 1 X 10(4) to 7.6 X 10(6) per wet gram of tumor. The TIL preparations separated by differential centrifugation on Ficoll-Hypaque gradients contained 10-95% of T11+ cells (mean 50%), and tumor cells accounted for the other major cellular component. Macrophages, NK cells, B cells and granulocytes were infrequently seen. Morphologically, TIL-T were small non-activated cells. They expressed the T11 and T3 antigens but not the receptor for IL-2 (IL-2R) or HLA-DR antigens as determined by double immunofluorescence staining. Rare T11+/IL-2R+ cells were recovered only from colon and lung carcinomas. The mean T4/T8 ratio in 12 TIL preparations was 1.1 +/- 0.8. Immunohistology with monoclonal antibodies (MAbs) performed in 31/35 tumors confirmed that the T11+ cells infiltrating solid tumors rarely expressed the IL-2R and that the cell content of suspensions enriched in TIL was comparable to that determined in situ. The recovered TIL were cloned in a microculture system that permits proliferation of nearly all normal peripheral blood T lymphocytes (PBL-T). Under these culture conditions, frequencies of the proliferating T lymphocyte precursors (PTL-P) were depressed in both the TIL preparations (less than 0.01 to 0.39) and patients' PBL-T (0.05 to 0.5). These low frequencies of PTL-P were seen in patients with all tumor types, both primary and metastatic.

Lymphoreticular infiltrates in invasive ductal breast cancer. A histological and immunohistological study

Fifty-two invasive ductal breast cancers were investigated histologically and immunohistologically to assess localization and composition of the lymphoreticular infiltrates. The tumour-infiltrating cells were mainly located in the intervening stroma, whereas tumour foci often exhibited lower numbers of lymphoreticular cells. Macrophages (Mono 1+ and KiM 6+) and helper/inducer cells bearing the T4 surface antigen (Leu-3a+) regularly constituted the majority of the tumour-infiltrating lymphoreticular cells. In more than 80% of cases large numbers of macrophages were found, and many T4 cells occurred in about 60%. Next in frequency were the T lymphocytes (Leu-1+) which were mostly observed in high (46%), or in moderate (39%) numbers. In about 2/3 of the cases moderate numbers of T8 (suppressor/cytotoxic) lymphocytes (Leu-2a+) were detected. B lymphocytes (T0 15+) and natural killer cells (Leu-7+) were generally encountered in very low numbers, while eosinophilic granulocytes were virtually absent from the lymphoreticular infiltrates. Tissue mast cells and plasma cells were present in very low numbers in about one half of the tumours but cases with low, moderate or - rarely - even high numbers of infiltrating cells also occurred. It must be emphasized that an in situ histomorphological analysis of the cellular part of the stromal reaction of invasive ductal breast cancers allows only limited conclusions concerning the functional properties of the tumour-infiltrating lymphoreticular cells. From the present study, macrophages and T4 cells but also T8 lymphocytes might be of significance in immunooncological reactions "against" clinically detectable stages of invasive breast cancer.