Prognostic significance of immunological evaluation in colorectal cancer

Possible Roles of Interleukin-4 and -13 and Their Receptors in Gastric and Colon Cancer

Interleukin (IL)-4 and -13 are structurally and functionally related cytokines sharing common receptor subunits. They regulate immune responses and, moreover, are involved in the pathogenesis of a variety of human neoplasms. Three different receptors have been described for IL-4, but only IL-4 receptor type II (IL-4Rα/IL-13Rα1) is expressed in solid tumors. While IL-13 can also bind to three different receptors, IL-13 receptor type I (IL-4Rα/IL-13Rα1/IL-13Rα2) and type II (IL-4Rα/IL-13Rα1) are expressed in solid tumors. After receptor binding, IL-4 and IL-13 can mediate tumor cell proliferation, survival, and metastasis in gastric or colon cancer. This review summarizes the results about the role of IL-4/IL-13 and their receptors in gastric and colon cancer.

Phenotype of Peripheral Blood Leukocytes and Survival of Patients with Metastatic Colorectal Cancer

Immune dysfunction is prevalent in metastatic cancer. Few patients with colorectal cancer metastases are cured, and among the strategies aimed at improving the therapeutic results in patients with metastatic colorectal cancer, immunotherapy is being increasingly investigated. We evaluated retrospectively the prognostic significance of peripheral blood leukocytes in 59 patients with metastatic colorectal cancer. The relative numbers of CD3+, CD3+CD4+, CD3+CD8+, NK (CD3-CD16+CD56+), CD3+DR+, CD3+CD25+, CD3+CD69+, CD19+, CD19+CD23+, CD8+CD28+, CD8-CD28+, CD8+CD57+, CD14+DR+ and CD14+CD16+ leukocytes were analyzed by two-color flow cytometry. A three-step approach was adopted to identify predictors of prognosis using regression analysis. Based on the results of univariate survival analysis, the absolute number of white blood cells, NK/CD3+CD69+ and NK/white cell count ratios were significant indicators of prognosis. In the multivariate regression analysis a model was obtained using a single parameter, the NK/CD3+CD69+ ratio, predicting the survival with 10–15% power of regression. The present results indicate that the NK/CD3+CD69+ ratio in peripheral blood may be an independent variable in a regression model predicting the overall survival of patients with colorectal cancer metastases to be tested in prospective studies.

Serum cytokine concentrations, flavonol intake and colorectal adenoma recurrence in the Polyp Prevention Trial

Background:

Serum cytokine concentrations may reflect inflammatory processes occurring during the development of colorectal neoplasms. Flavonols, bioactive compounds found in plant-based foods and beverages, may inhibit colorectal neoplasms partly by attenuating inflammation.

Methods:

Using logistic regression, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) to investigate the association between serum concentrations of interleukin (IL)1β, 2, 8, 10, 12p70, granulocyte macrophage colony stimulating factor, interferon-γ, and tumour necrosis factor-α, measured over time, flavonol intake, estimated from a flavonol database used in conjunction with a food frequency questionnaire, and adenoma recurrence in 872 participants from the intervention arm of the Polyp Prevention Trial.

Results:

Decreased IL-2 concentration during the trial increased the risk of any adenoma recurrence (4th vs 1st quartile, OR=1.68, 95% CI=1.13–2.49), whereas decreased IL-1β or IL-10 reduced the risk of advanced adenoma recurrence (OR=0.37, 95% CI=0.15–0.94; OR=0.39, 95% CI=0.15–0.98, respectively). Individuals with flavonol intake above the median (29.7 mg per day) and decreased cytokine concentrations had the lowest risk of advanced adenoma recurrence.

Conclusion:

Overall, no consistent associations were observed between serum cytokine profile and colorectal adenoma recurrence; however, decreased cytokine concentrations during high flavonol consumption may indicate prevention of colorectal neoplasms.

Preoperative interleukin-6 production by mononuclear blood cells predicts survival after radical surgery for colorectal carcinoma

BACKGROUND

Colorectal cancer is one of the most common forms of cancer in the Western world. Staging based on histopathology is currently the most accurate predictor of outcome after surgery. Colorectal cancer is curable if treated at an early stage (stage I-III). However, for tumors in stages II and III there is a great need for tests giving more accurate prognostic information defining the patient population in need of closer follow-up and/or adjuvant therapy. Furthermore, tests that provide prognostic information preoperatively could provide a guide both for preoperative oncologic treatment and the surgical procedure.

METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated preoperatively, within a week before primary surgery, from 39 patients undergoing surgery for colorectal cancer. The PBMCs were cultured in vitro for 24 hours in the presence of autologous serum and lipopolysaccharide (LPS). Interleukin-6 (IL-6) production was measured with enzyme-linked immunosorbent assay (ELISA). Staging based on histopathology was performed in all patients. Patients were followed for at least 54 months.

RESULTS

A production of >5000 pg/mL of IL-6 identified colorectal cancer patients with a poor prognosis. Eight out of 13 patients with >5000 pg/mL IL-6 died from cancer within the follow-up period, whereas no cancer-related deaths were recorded among 21 patients with 5000 pg/mL IL-6 or less. A multivariate Cox regression analysis, stratified for T- and N-stage, identified IL-6 production as an independent prognostic factor.

CONCLUSIONS

IL-6 production in vitro by PBMC can predict survival after radical surgery for colorectal cancer.

Are immunological mechanisms involved in colon cancer and are they possible markers for biotherapy improvement?

This paper focuses on our data on colon cancer patients. Our overall results lead us to believe that the suppressive effect of specific cytokines in colon cancer patients alters the functionality of TH1 and TH2 subsets of CD4+ T-cells, with an expansion of TH2 cells and a malfunctioning of TH1 cells. This immunological disregulation appears to increase with stage progression, suggesting a direct role in the mechanisms that allow the tumour to locate and expand within the host. It is also clear that in order to identify disease markers and generate an in vivo immune response that corrects the imbalance between TH1 and TH2 cells, we need to understand how tumour mechanisms cause this imbalance to begin with.

The Study of a Patient's Immune System May Prove to be a Useful Noninvasive Tool for Stage Classification in Colon Cancer

Therapy, and, therefore, prognosis, is strictly related to cancer stage, and hence, screening tests that can contribute to the early classification of disease stage represent a step forward in treatment. Unfortunately, few prognostic indices are available, especially noninvasive ones. Our study of the physiological network of the immune response, however, leads us to believe that it may well be possible to define immunological indices for the classification of cancer stage using blood parameters. In this paper, we show how the study of a patient's immune system can be used as a noninvasive tool for early-stage classification.

The correlation between colorectal cancer rates of proliferation and apoptosis and systemic cytokine levels; plus their influence upon survival

Colorectal cancer development is associated with a shift in host immunity with suppression of the cell-mediated immune system (CMI) and a predominance of humoral immunity (HI). Tumour progression is also associated with increased rates of cell proliferation and apoptosis. The aim of this study was to investigate whether these factors correlate and have an influence upon prognosis. Long-term follow-up was performed on 40 patients with colorectal cancer who had levels of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma and interleukin (IL)-10 measured from stimulated blood cultures before surgery. Their archived tumour specimens were analysed to determine a Ki-67-derived proliferation index (PI) and a M30-derived apoptosis index (AI). Tumour necrosis factor-alpha levels negatively correlated to tumour proliferation (rho=-0.697, P=0.01). Interleukin-10 levels had a positive correlation with tumour proliferation (rho=0.452, P=0.05) and apoptosis (rho=0.587, P=0.01). Patient survival correlates to tumour pathological stage (P=0.0038) and vascular invasion (P=0.0014). An AI< or =0.6% and TNF-alpha levels > or =8148 pg ml(-1) correlate to improved survival (P=0.032, P=0.021). Tumour proliferation and apoptosis correlate to progressive suppression of the CMI-associated cytokine TNF-alpha and to and higher levels of IL-10. Survival is dependent upon the histological stage of the tumour, vascular invasion, rates of apoptosis and proliferation and systemic immunity which are all interconnected.

Progressive loss of endothelial P-selectin expression with increasing malignancy in colorectal cancer

Adhesion of inflammatory cells to vascular endothelium is mediated by specific cell adhesion receptors on both leukocytes and endothelial cells. One of the adhesion molecules on the endothelium is P-selectin. Decreased vascular P-selectin expression has been associated with tumor progression in melanoma patients. We now report on the expression of endothelial P-selectin in colorectal cancer (CRC). We studied a colorectal tissue specimen series ranging from normal colorectal tissue via unmetastasized primary tumors to tumors with the same depth of invasion at the primary site but with liver metastases. Moreover, P-selectin expression levels in liver metastases were determined. The number of P-selectin positive vessels as a fraction of the total number of vessels, both intra- and peritumorally, was determined by staining for CD62P and CD34, respectively. Furthermore, by immunostaining for leukocytes (CD45) and macrophages (CD68), it was evaluated whether levels of P-selectin expression influenced infiltrate density and composition. The results showed that levels of peritumoral P-selectin expression were reciprocal to the degree of progression in CRC. This relation was even more pronounced intratumorally: in metastasized primary tumors and in the metastatic lesions, P-selectin expression was virtually absent. This distribution pattern was reflected in the numbers of leukocytes that accumulated in the various tissues, since in the primary tumors with metastases, and in the metastatic lesions, hardly any infiltrating cells were observed. In these lesions, leukocytes were present in the peritumoral zone, but seemed unable to enter the tumor tissue. In primary tumors without metastasis, the intratumoral leukocyte infiltration density was significantly higher. Recruitment levels of macrophages remained constant throughout the different tissues. We suggest that downregulation of endothelial P-selectin expression is a mechanism by which CRC lesions evade inflammatory regression and, thereby, progress to a more advanced stage of malignancy.

Passage from normal mucosa to adenoma and colon cancer: alteration of normal sCD30 mechanisms regulating TH1/TH2 cell functions

The pathogenesis of cancer is currently under intensive investigation to identify reliable prognostic indices for the early detection of disease. Adenomas have been identified as precursors of colorectal cancer and tumor establishment, and disease progression has been found to reflect a malfunction of the immune system. On the basis of the role of the CD30 molecule in the regulation of TH1/TH2 functions and our previous results, strongly suggesting the validity of serum TH1/TH2 cytokines in the study of tumor progression, we studied network interaction between the production of soluble (s) CD30/sBCl2 in whole blood culture [in basic conditions and after PHA, LPS, and anti-CD3 monoclonal antibody (mAb) stimulation] and levels of TH1/TH2 cytokines (IL2, IFN gamma, IL12, IL4, IL5, IL10). Peripheral blood from a group of healthy subjects, as well as from patients with adenoma and colorectal cancer was used. Our objective was to gain a better insight into the role of the CD30 molecule in the passage from normal mucosa to adenoma and tumor and identify specific disease markers. Our results suggest that the decrease in CD30 expression and the abnormal increase in Bcl2 expression, observed in the peripheral cells of both adenoma and tumor groups determine an imbalance between TH1/TH2 functions. Consequently, changes in sCD30/sBcl2 culture production and TH1/TH2 cytokine serum levels may be reliable markers for tumor progression. In fact, our overall data show that a decrease of sCD30 levels in basic and PHA conditions and an increase of IFN gamma, IL4, IL5, and IL12 serum levels and sBcl2 in all activation condition are indicative of the passage from normal mucosa to adenoma; whilst a decrease of sBcl2 level in basic, LPS and anti-CD3 conditions and of IL2, IFN gamma serum levels, together with an increase of IL5 are indicative of the passage from adenoma to tumor.

Immune system effects of echinacea, ginseng, and astragalus: a review

Traditional herbal medicine provides several remedies for strengthening the body's resistance to illness through effects on immune system components. This review article examines 3 popular herbal immune stimulants that are often of interest to cancer patients. Echinacea, a native of North America, is widely used to prevent, or provide early treatment for, colds. Preclinical studies lend biological plausibility to the idea that echinacea works through immune mechanisms. Numerous clinical trials have been carried out on echinacea preparations: it appears that the extracts shorten the duration and severity of colds and other upper respiratory infections (URIs) when given as soon as symptoms become evident. However, trials of long-term use of echinacea as a preventive have not shown positive results. Ginseng has been studied in some depth as an antifatigue agent, but studies of immune mechanisms have not proceeded so far. Preclinical evidence shows some immune-stimulating activity. There have been several clinical trials in a variety of different diseases. Astragalus is the least-studied agent. There are some preclinical trials that show intriguing immune activity. The herbs discussed appear to have satisfactory safety profiles. Cancer patients may wish to use these botanicals to inhibit tumor growth or to boost resistance to infections. However, passive immunotherapy with herbs, with no mechanism to expose tumor antigens, is unlikely to be effective in inhibiting tumor growth. Although the margin of safety for these herbs is large, more research is needed to demonstrate the clear value of using herbs to improve resistance to infections.

Peripheral blood immunological parameters for use as markers of pre-invasive to invasive colorectal cancer

In cancer, the extent to which the disease has spread is probably the most important factor in determining patient prognosis. Hence practical and non-invasive methods are needed to identify disease stage. In a previous paper we showed how diagnostic and prognostic indices for disease progression could be defined by evaluating parameters in peripheral blood. The aim of this study was to identify further serum parameters that could be used. Serum levels of interferon (IFN) gamma, interleukin (IL)4, IL8, IL7, IL1 beta, tumor necrosis factor (TNF) alpha, granulocyte macrophage-colony stimulating factor (GM-CSF), soluble (s) IL2 receptor (R) and sIL6R were studied but only levels of IL4, sIL2R, IL8 and IL7 were found to be significant and would therefore be of use in defining diagnostic and prognostic indices for disease progression. In further detail, our results indicate that when serum levels of sIL2R < 522 U/ml, IL4 < 159 pg/ml and IL8 > 339 pg/ml there is a 95% probability that the disease is in stage I or II where there is no infiltration of lymph nodes; when serum levels of sIL2R > or = 522 Ug/ml, 159 pg/ml < or = IL4 < or = 319 pg/ml, and IL7 < 54 pg/ml, there is a 95% probability that the disease is in stage III and the tumor has invaded the lymph nodes; when the serum levels of IL4 > or = 431 pg/ml and IL7 > or = 54 pg/ml, there is a 95% probability that the disease is in stage IV and there is metastasis.

Disease stage prognostic indices in the early clinical screening of colorectal cancer patients

It is a truism to state that in cancer the extent to which the disease has spread (stage) is probably the most important factor determining patient prognosis and must be given prime consideration in evaluating and comparing different therapeutic regimes. Because of this, clinical screening tests (such as a rectal exam proctoscopy and colonoscopy), if tissue that is not normal is found, should include analyses contributing to the patient disease stage classification. However, the difficulty involved in this, principally due to the absence of reliable early prognostic indices of the disease stage, makes the cancer patients' treatment full of problems and risks. By a retrospective statistical study on pre-surgery peripheral blood immunological parameters of our groups of colorectal cancer patients and healthy subjects, we evaluated our previously suggested possibility of defining stage prognostic indices by parameter blood range values, evaluating their ability in the stage classification compared to the pTNM method. We have investigated the serum levels of various cytokines and cytokine receptors, leukocyte surface markers, peripheral blood mononuclear cell (PBMC) cytokine production and PBMC proliferative response. Statistically significant correlations between a variety of these immunological parameters and the disease stage were found, but as a clinical patient screening of all parameters is quite expensive, to identify the greatest stage weighting parameter and the respective blood range values, we performed a multivariate statistical analysis. We found that the blood ranges of IL-4 serum level and the PBMC proliferative response to anti-CD3 monoclonal antibody (mCD3) stimulus may be reliable prognostic indices which may contribute to an early disease stage classification in colorectal cancer patients, since they seem to be valid as the pTNM method. Moreover, as the immunological prognostic indices could be a useful tool to evaluate the patient immune response, they may also improve the definition of the patient's stage classification for the selection of treatment and restaging procedures for the evaluation of the treatment benefit and recurrent disease.

The role of the soluble CD30 serum level in colorectal cancer: a possible marker for a patient subset which could benefit from IL-2 biotherapy

On the basis of our previous data suggesting an impairment in host immune response in colorectal cancer caused by an inappropriate switch from TH1 towards TH2 cells, we investigated the role of the soluble CD30 (sCD30) in this disease, as this molecule was found related to immune responses characterized by the activation of a prevalence of TH2 cells. We studied a group of healthy subjects and colorectal cancer patients determining the sCD30 serum level and the following immunological parameters: s interleukin-2 receptor (sIL-2R), IL-2, interferon (IFN) gamma, IL-6, IL-4 and IL-10 levels in the serum and peripheral blood mononuclear cell (PBMC) production; PBMC proliferative responses to IL-2, anti-CD3 monoclonal antibody (CD3) and IL-2 + CD3. Our overall data indicate that in colorectal cancer the sCD30 serum level is also linked to a prevalence of the TH2 immune response activation. However, the Multivariate statistical study underlines that the sCD30 level is principally related to the IL-6 TH2 cytokine. Moreover, it suggests that in colorectal cancer, the sCD30 level might be a marker for identifying a patient subset in which IL-2 biotherapy treatment could contribute to the restoration of the impaired immune system.

IL-10 and sIL-2R serum levels as possible peripheral blood prognostic markers in the passage from adenoma to colorectal cancer

The pathogenesis of cancer is currently under intense investigation to identify reliable prognostic indices for the early detection of disease. Adenomas have been identified as precursors of colorectal cancer and tumor establishment, and disease progression has been found to reflect a malfunction of the immune system. We previously indicated the investigation of cytokine serum levels in these patients as a useful and non-invasive tool for the study of the disease progression and an imbalance at TH1 and TH2 cell levels was also found. Moreover, the soluble form of interleukin (IL) 2 receptor (sIL-2R) level is an in vivo marker of T cell activation and is used to monitor the activation of the immune system. We therefore performed an immunological study on a group of healthy subjects, subjects with adenomas, and colorectal cancer patients to identify peripheral blood invasiveness markers in the progression from normal mucosa through adenoma to tumor. In this paper we evaluated the relationships between serum levels of interleukin IL-2, sIL-2R, interferon (IFN) gamma, IL-4, IL-6, IL-10 and sICAM-1 and their networks. Our overall data indicate that in the normal mucosa through adenoma to tumor progression, the host immune response proceeded from a TH1 cell-mediated immune response type (healthy subjects) to a type with TH2 suppressive characteristics (adenoma subjects and cancer patients). However, in the adenoma subjects there was no IL-10 or sIL-2R involvement, while these parameters were implicated in the cancer patients' immune responses. Moreover, a concurrent augmentation of sIL-2R and IL-10 levels seems to be prognostic for the passage from adenoma to cancer, and the sIL-2R and sICAM-1 molecules appear to be involved in the invasiveness mechanisms.

The sCEA molecule suppressive role in NK and TH1 cell functions in colorectal cancer

The soluble form of carcinoembryonic antigen (sCEA), an oncofetal glycoprotein, is frequently produced by human epithelial-tumor cells, particularly of colorectal origin, and evaluated as a prognostic index of tumor progression and patient survival. sCEA molecules are often present at high concentrations in the peripheral blood of colorectal cancer patients, but the function and significance of this are not well understood. Reported data have demonstrated that sCEA can interfere in NK-cell/tumor-cell interaction by drastically reducing the lysis of tumor cells in a dose-dependent manner and can also suppress T and B cell functions. The aim of our study was to evaluate this situation in colorectal cancer by determining peripheral blood immunological parameters in a group of patients and healthy subjects. We evaluated the interleukin (IL)-2, interferon (IFN) gamma, IL-4, sIL-2R and IL-10 levels in the serum and the release of IFN gamma, IL-4 and IL-10 from peripheral blood mononuclear cells (PBMC); the PBMC expression of CD3, CD16 and CD19 phenotypic antigens; the PBMC proliferative responses to IL-2, IL-2 + anti-CD3 monoclonal antibody (mCD3) and mCD3. The statistical evaluation of our overall results strongly indicates that the high level of the sCEA molecules in the patient's serum might act as a suppressive factor for NK and TH1 immunocompetent cells. This may be the cause of sCEA involvement in tumor progression, and indicates the possibility of an improvement in cancer treatment through its manipulation.