Lymphoreticular cells within primary colorectal carcinoma: a surface marker study

Intercellular adhesion molecule-1 expression by macrophages in human gastrointestinal carcinoma: possible roles as host immune/inflammatory reaction

Tumor-associated macrophages (TAM) are one of the factors which modulate the carcinoma progression. The present study described immunohistochemical expression of intercellular adhesion molecule-1 (ICAM-1) in stromal cells in human gastrointestinal carcinoma identifying the cell types by immunoelectron microscopy. In colon and gastric carcinomas, ICAM-1-positive cells were mostly stromal cells, and major cell types were identified as macrophages and fibroblasts by immunoelectron microscopy. Macrophages were characterized by their ovoid shape, cytoplasmic projections, abundant vacuoles, phagocytosis, and paucity of rough endoplasmic reticulum. Fibroblasts contained stacks of rough endoplasmic reticulum. Macrophages were major cells among ICAM-1-positive cells along the invasive margin, while fibroblasts were predominant in the stroma within carcinoma in colon and intestinal-type gastric carcinomas. Lymphocytes positive for lymphocyte function associated antigen (LFA-1), a counter-receptor of ICAM-1, were densely distributed along the invasive margin, and sparsely in the stroma within carcinoma. In diffuse-type gastric carcinoma, most macrophages were dendritic-shaped and negative for ICAM-1. Our study suggests that the invasive margin is an area similar to active inflammation, where the antigen presenting cells (macrophages) and lymphocytes may interact via the ICAM-1/LFA-1 adhesion.

Lymphocytes infiltrating colorectal cancer have low proliferative capacity but can secrete normal levels of interferon gamma

Significant numbers of infiltrating mononuclear cells are commonly observed in solid tumours, although their role in restricting tumour growth is not clear. Tumour-infiltrating lymphocytes (TIL) from 38 patients with colorectal cancer, in parallel with peripheral blood lymphocytes (PBL), were assayed to determine their ability to proliferate in response to concanavalin A (ConA), interleukin-2 (IL-2), ConA+IL-2, phorbol 12-myristate 13-acetate (PMA)+ionomycin ionomycin (IOM), and staphylococcal enterotoxin B(SEB). These reagents were selected to give a range of weak to strong proliferative responses either via or independent of the T cell receptor. Proliferation of TIL was significantly lower than that of PBL in all cultures: ConA (P < 0.001), IL-2 (P = 0.002), ConA+IL-2 (P < 0.001), PMA+IOM (P < 0.001), SEB (P = 0.002). In addition to the low proliferative capacity of TIL, production of cytokines by TIL may also play a role in control of tumour growth. We have assayed IFN gamma production in the supernatants from 16 paired TIL and PBL cultures, and tumour necrosis factor alpha (TNF alpha) in 6 paired cultures. TNF alpha concentrations were significantly lower in TIL cultures than in PBL cultures stimulated with ConA (P < 0.05), but no different in control or IL-2 stimulated cultures. IFN gamma levels did not significantly differ between PBL and TIL cultures, indicating that despite the restricted proliferative capacity of TIL, these cells remain capable of secreting significant amounts of IFN gamma.

Cell adhesion molecule expression by vascular endothelial cells as an immune/inflammatory reaction in human colon carcinoma

The cell adhesion of inflammatory cells to vascular endothelial cells is an important process in the recruitment of inflammatory cells to the site. In cancer tissue, infiltration of inflammatory cells has been suggested to be a mechanism of host resistance. To clarify this infiltration mechanism, we investigated cell adhesion molecule expression (E-selectin, P-selectin, and ICAM-1) in vascular endothelial cells by immunohistochemistry in colon carcinoma. Venules distributed along the invasive margin expressed E- and P-selectins and ICAM-1. These phenotypical features are identical to those of endothelial cells observed in active inflammatory lesions, and the vessels can, therefore, be designated as immunologically activated vessels. Nevertheless, the majority of blood vessels within the tumor lacked immunoreactivity for all these adhesion molecules and, therefore, could be designated as immunologically inactive vessels. Granulocytes, lymphocytes and macrophages, bearing the counter-receptors of these adhesion molecules, were more densely distributed along the invasive margin. In contrast, few inflammatory cells were present within the tumor. In conclusion, the present study has demonstrated the phenotypical heterogeneity of tumor vessels; those for inflammatory cell infiltration to the tumor and those for the nutrient supply to the tumor.

Functional evaluation of tumor-infiltrating mononuclear cells. Detection of endogenous interferon-gamma and tumor necrosis factor-alpha in human colorectal adenocarcinomas

Quantitative evaluation of the levels of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) in the extracts of tumors and their corresponding normal tissues resected from 43 patients with colorectal adenocarcinoma was done using solid-phase, sandwich radioimmunoassay. The levels of both IFN-gamma and TNF-alpha detected in the tumor tissues were higher than those in the corresponding normal colorectal tissues obtained from each patient. A significant negative correlation was observed between the level of IFN-gamma and TNF-alpha in each tumor extract. The decrease of the level of IFN-gamma in the tumor correlated with the advance of clinical stage, and the levels of IFN-gamma of the patients with distant metastases were significantly lower than those of the patients without distant metastases. However, an increase in the level of TNF-alpha correlated not only with an enlarged diameter but also with the extent of the primary tumor. Immunohistochemical staining of IFN-gamma and TNF-alpha producing cells in tumor tissues showed that IFN-gamma was mainly produced by CD4+ CD8- T-lymphocytes and TNF-alpha was mainly produced by CD11c+ cells with macrophage-like morphology. These results suggest that CD4+ T-lymphocytes that produce IFN-gamma might play an important role in the antitumor response against cancer progression in human colorectal adenocarcinomas.

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.