Local expression and circulating form of ICAM-1 in colorectal cancer

A role for serum cytokines and cell adhesion molecules in the non‑invasive diagnosis of colorectal cancer

Colorectal cancer (CRC) remains a major cause of cancer-related mortality. Consequently, new diagnostic and therapeutic approaches are being investigated including the serum levels of cytokines and other molecules, although the results are often inconclusive. Thus, the present study aimed to determine whether serum level of cytokines, cell adhesion molecules or matrix metalloproteinases (MMPs), alone or in combination, may contribute to the non-invasive diagnosis of CRC. The serum levels of nine cytokines [ILs; IL-1β, IL-4, IL-6, IL-8, IL-10, IL-17, IL-22 and IL-33, and interferon (IFN)-γ], two cell adhesion molecules (intercellular adhesion molecule-1 and P-selectin) and an MMP-7 were measured by ELISA in 33 patients with CRC and 35 healthy controls. Combined capacity of all molecules to detect the presence of CRC was assessed by logistic regression. Molecules and molecule combinations were tested for all stages and tumor grades. A significant increase was identified for IL-8 in patients compared with healthy controls; IL-10 was found to be significantly decreased. The biomarker potential of each significantly modified molecule was tested: IL-8 had a sensitivity of 0.865, a specificity of 0.600 and an area under the curve (AUC) of 0.777; for IL-10, sensitivity was 0.65, specificity was 0.69, with an AUC of 0.689. Logistic regression determined the best discriminative potential between patients and control groups for the combination IL-4 + IL-6 + IL-8 + IFN-γ, with 0.97 sensitivity and 0.58 specificity. For the early stages of CRC, the combination IL-6 + IL-8 + IL-22 showed good performance. It was concluded that increased IL-8 had potential as single biomarker in CRC. Cytokine combinations are superior to single cytokine analysis in showing the presence of CRC.

Dicer-regulated microRNAs 222 and 339 promote resistance of cancer cells to cytotoxic T-lymphocytes by down-regulation of ICAM-1

The RNase III endonuclease Dicer plays a key role in generation of microRNAs (miRs). We hypothesized that Dicer regulates cancer cell susceptibility to immune surveillance through miR processing. Indeed, Dicer disruption up-regulated intercellular cell adhesion molecule (ICAM)-1 and enhanced the susceptibility of tumor cells to antigen-specific lysis by cytotoxic T-lymphocytes (CTLs), while expression of other immunoregulatory proteins examined was not affected. Blockade of ICAM-1 inhibited the specific lysis of CTLs against Dicer-disrupted cells, indicating a pivotal role of ICAM-1 in the interaction between tumor cells and CTL. Both miR-222 and -339 are down-regulated in Dicer-disrupted cells and directly interacted with the 3' untranslated region (UTR) of ICAM-1 mRNA. Modulation of Dicer or these miRs inversely correlated with ICAM-1 protein expression and susceptibility of U87 glioma cells to CTL-mediated cytolysis while ICAM-1 mRNA levels remained stable. Immunohistochemical and in situ hybridization analyses of 30 primary glioblastoma tissues demonstrated that expression of Dicer, miR-222, or miR-339 was inversely associated with ICAM-1 expression. Taken together, Dicer is responsible for the generation of the mature miR-222 and -339, which suppress ICAM-1 expression on tumor cells, thereby down-regulating the susceptibility of tumor cells to CTL-mediated cytolysis. This study suggests development of novel miR-targeted therapy to promote cytolysis of tumor cells.

Adipose tissue in Walker 256 tumour-induced cachexia: possible association between decreased leptin concentration and mononuclear cell infiltration

The adipose tissue (AT) is severely affected by cachexia, a paraneoplastic syndrome, which increases the morbidity and mortality of cancer. There is, however, a heterogeneous response to the condition, according to the AT depot. As plasma leptin concentration has been often reported to vary in cachexia, we have measured (species specific radioimmunoassay) the local concentration of leptin in three AT depots: retroperitoneal (RPAT), epididymal (EAT) and mesenteric (MES) of Walker 256 tumour-bearing rats. A reduced concentration of leptin ( P<0.0001) was found in all the depots and in the plasma of the cachectic rats, compared with controls already from day 4 after tumour cell injection. The presence of a cell infiltrate was observed in all AT obtained from the tumour-bearing animals. Ultrastructural analysis, along with immunocytochemistry for RT1B (indicating the presence of MHCII) and using antibody against mononuclear phagocytes, showed the cells to be macrophages. The profile of TNFalpha and PGE2 secretion by the infiltrate was investigated (commercial kits). There was increased production of both factors by the cells of all AT ( P<0.05) compared with peritoneal macrophages obtained from the cachectic rats, while the cells isolated from MES showed the highest synthesis of TNFalpha. The results suggest a possible modulation of the chronic locally produced TNFalpha and PGE2 upon leptin synthesis by the AT of the cachectic rats.

Expression of intercellular adhesion molecule (ICAM)-1 in adenoid cystic carcinoma of the head and neck

OBJECTIVES/HYPOTHESIS

Adenoid cystic carcinoma of the head and neck (ACCHN) is characterized by late recurrence and frequent distant metastasis. Tumor attack by cytotoxic T lymphocytes and macrophages is mediated by the interaction of leukocyte function-associated antigen (LFA)-1 on lymphocytes with intercellular adhesion molecule (ICAM)-1 on the tumor surface. Thus, the reduced expression of ICAM-1 on tumor cells could contribute to their escape from host immune surveillance. To investigate the relationship between the clinical features of ACCHN and host immune surveillance, the expression of ICAM-1 and infiltration of T/natural killer (NK) cells and macrophages were immunohistochemically examined.

STUDY DESIGN

Retrospective analysis of immunohistochemical tumor characteristics and clinical outcome.

METHODS

Immunohistochemical study of ICAM-1, T/NK cells, and macrophages was performed on paraffin sections of 42 patients with ACCHN. The expression of T/NK cells and macrophages was represented by T-cell-restricted antigen (TIA)-1 and CD68 expression, respectively. The expression of these molecules and clinical features were analyzed.

RESULTS

Of 42 ACCHN cases, 15, 9, and 15 patients were classified as ICAM-1 high, TIA-1 high, and CD68 high, respectively. The TIA-1 expression scores in ICAM-1-low patients were significantly lower than those in ICAM-1-high patients (1.3 +/- 3.7 vs. 8.3 +/- 12.7, P =.0031). The CD68 expression scores in ICAM-1-low patients were also significantly lower than those in ICAM-1-high patients (9.6 +/- 9.6 vs. 21.1 +/- 17.6, P =.0047). Moreover, ICAM-1-high patients had a significantly better disease-free survival rate (P =.043).

CONCLUSIONS

Reduced expression of ICAM-1 may promote immune evasion and metastasis, resulting in poor prognosis in ACCHN.

Reduced expression of intercellular adhesion molecule-1 in ovarian adenocarcinomas

Ovarian adenocarcinomas develop as the result of multiple genetic and epigenetic changes in the precursor ovarian surface epithelial (OSE) cells which result in a malignant phenotype. We investigated changes in gene expression in ovarian adenocarcinoma using a cDNA array containing 588 known human genes. We found that intercellular adhesion molecule-1 (ICAM-1) was expressed at lower levels in the ovarian tumour cell lines OAW42, PEO1 and JAM than in the immortalised human ovarian surface epithelial cell line HOSE 17.1. Further investigation revealed ICAM-1 was expressed in the surface epithelium of normal ovaries and both mRNA and protein expression levels were reduced in the majority of ovarian adenocarcinoma cell lines and primary tumours. ICAM-1 expression was increased in 8/8 cell lines treated with the de novo methyltransferase inhibitor 5-aza-2'-deoxycytidine, indicating that methylation of CpG islands may play a role in the down-regulation of its expression in primary tumours. There was a significant association between patients whose tumours expressed ICAM-1 and survival (P = 0.03), suggesting that expression levels of ICAM-1 may have clinical relevance.

ICAM-1 (intercellular adhesion molecule-1) gene transfection inhibits lymph node metastasis by human gastric cancer cells

Lymph node metastasis is one of the prognostic factors in gastric cancer. We have previously reported that decreased intercellular adhesion molecule-1 (ICAM-1) expression on cancer cells is associated with lymph node metastasis using a gastric cancer cell. In this study, we transfected ICAM-1 gene into a gastric cancer cell line, 2MLN, and analyzed the effect on lymph node metastasis in vitro and in vivo. A significantly greater amount of peripheral blood mononuclear cells (PBMC) adhered to ICAM-1 transfected 2MLN cells, 2MLN / ICAM cells, than to 2MLN / Vector cells. The lysis of 2MLN / ICAM cells by PBMC was significantly increased compared with that of 2MLN / Vector cells. The tumor growth rate of 2MLN / ICAM cells was significantly decreased in vivo. Lymph node metastases caused by 2MLN / ICAM cells were recognized as being fewer in number and smaller, while many lymph node metastases were caused by 2MLN cells. Histologic findings showed that leukocytes were heavily infiltrated in both the 2MLN / ICAM tumors and metastatic lesions, while only a few leukocytes were observed in the lesions associated with 2MLN cells. The above findings indicate that ICAM-1 gene transduction could prove to be an effective gene therapy for lymph node metastasis of gastric cancer.

The effect of Walker-256 tumour development upon Kupffer cell metabolism

The liver plays a central role in the establishment and maintenance of the cachectic state in rats bearing extra-hepatic tumours. Kupffer cells, which as macrophages, show a strong relationship between metabolism and function could be involved in the alterations observed in the disruption of many functions of the organ as a whole. To assess whether the metabolic/functional pattern of Kupffer cells was altered by cachexia we have investigated the utilization of glucose, glutamine and palmitate by the cells from tumour-bearing and control rats. We have found an enhanced utilization of the three substrates by the cells from tumour-bearing rats as compared with controls, which was related to greater energy production through the Krebs cycle and enhanced production of precursors for the synthesis of the many substances the cells secrete when activated. The use of palmitate as substrate was also augmented in these cells, in the opposition to the observation in stimulated peritoneal macrophages. The availability of palmitate however, was not associated with a reduction of glucose or glutamine consumption. The cycle of interconversion, free fatty acids/triacyglycerol in Kupffer cells from tumour-bearing rats was also found to be increased, as was hydrogen peroxide production. Taken together the results suggest an increased utilization of substrates for both energy production and for synthetic processes (e.g. NADPH for hydrogen peroxide production).