Immunological implications of alterations in the c-Ki-ras and p53 genes in the stepwise progression of colorectal cancer: indications for the improvement of prognosis, biotherapy treatment and tumor biology understanding

Alterations in gene structure and functions involving the c-Ki-ras and p53 genes have been shown to play an important role in the various stages of human colorectal carcinogenesis. However, how these gene alterations cooperate with tumoral mechanisms at an immunological level is not known. To this aim an immunological study of a group of healthy subjects, patients with p53 gene deletions (53D), with c-Ki-ras mutations (KrM) and no gene alterations (53D-KrM-) have made. In a previous study we found that a disregulation between TH1/Th2 cell functions seems to be implicated in the establishment and progression of colorectal cancer disease and that soluble interleukin (IL)-2Receptor (sIL-2R) serum level is involved in this. On this basis we investigated the immunological implications of p53 and c.Ki-ras gene alterations, evaluating the relationhips in the immune network between sIL-2R levels in the serum and immunological parameters (IL-2, IL-4 serum levels; CD3, CD16 and CD19 expression on the surface of peripheral blood mononuclear cells--PBMC). Our results suggest that, in the stepwise progression of colorectal cancer, the c-Ki-ras gene alteration is involved in a switch of the host immune response to a suppressive type which, as we have previously reported, may be a determining or concurrent cause of malignant transformation. Alteration in the p53 gene does not appear to ulteriorly impair the patients' immunological response. Our data supports the role of c-Ki-ras gene mutations and p53 deletions as prognostic markers in the passage of normal tissue to adenoma and adenoma to carcinoma respectively. Moreover, the evaluation of the mechanisms involved in the alterations of c-Ki-ras gene seems to be more important than that of p53 suppressor gene for the improvement of prevention, biotherapy treatment and tumor biology understanding.     

Prognostic significance of immunological evaluation in colorectal cancer

According to the concept that tumour establishment and progression generally reflects a malfunction of the immune system, we have investigated the prognostic significance of immunological parameters in correlation to stage progression in colorectal cancer. In patients and healthy subjects as control group, we determined: serum levels of interleukin (IL)-2, interferon (IFN) gamma, IL-4, IL-6, IL-7, IL-8, tumor necrosis factor (TNF) alpha cytokines and soluble IL-2 receptor (sIL-2R), CD30 (sCD30), ICAM-1 (sICAM-1) molecules, phenotype of peripheral blood mononuclear cells (PBMC); PBMC proliferative response to IL-2, IL-4 and anti-CD3 monoclonal antibody (anti-CD3) variously combined. Our results show that, compared to healthy controls, the group of all patients, but interestingly, also the groups of patients at the various stages of the disease, seem to have different values of these immunological parameters. Since tumour invasion and metastasis are the major causes of cancer treatment failure the early recognition of preinvasive states could lead to an improvement in prognosis. For this purpose our results might be especially useful in making prognostic and diagnostic indices in this neoplasy to identify patients at risk for tumour detention and the patient condition concerning disease progression by a non-invasive method. Moreover, this evaluation which contributes to identify the damage in the patient immune response to tumor could be helpful in identifying the therapeutic substances which might switch this response from being unproductive to productive. Thus, our data leads us to indicate that it might be possible to define reliable prognostic and diagnostic indices in colorectal cancer from the extension of this immunological study by the evaluation of these and other parameters.     

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.     

Loss of tumoral expression of soluble IL-6 receptor is associated with disease progression in colorectal cancer

Background:

Interleukin-6 (IL-6) binds both the membrane and soluble forms of the IL-6 receptor (sIL-6R), which induces a complex with gp130, and proliferation of tumour cells. The aim of this study is to clarify the relationship between tumoral sIL-6R expression and disease progression in colorectal cancer patients.

Methods:

We measured tissue concentrations of sIL-6R in tumour and normal mucosa from 161 colorectal cancer patients undergoing surgery, and in supernatants from colon cancer cell lines. The expression of IL-6, IL-6R and gp130 was evaluated by immunohistochemical analysis.

Results:

Loss of tumour expression of sIL-6R as defined by sIL-6R Ca/N ratio <1.0 was significantly associated with factors reflecting disease progression, and was an independent prognostic factor not only in all the patients in this study, but also in the patients with curative intent. Colon cancer cell lines produced sIL-6R in vitro, and the production of sIL-6R in cancer cell lines was stimulated by cytokine stimulation. Immunohistochemistry revealed that loss of tumour expression of sIL-6R was significantly inversely correlated with intense IL-6 expression in the cytoplasm of cancer cells. In addition, tumoral IL-1β expression was significantly correlated with sIL-6R expression.

Conclusion:

Loss of tumour expression of sIL-6R is associated with colorectal cancer disease progression.     

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.     

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.     

Necessity of biotherapeutic treatments inducing TH1 cell functions in colorectal cancer

Our previous data on colorectal cancer suggest that there are faults at the level of mechanisms of the proliferative responses of patients peripheral blood mononuclear cells (PBMC) to the interleukin (IL)-2 and IL-2 PBMC production, which increase with the stage advancement. The damages in the proliferative response seem to be eliminated by the costimulator effects of the signals produced by the anti-CD3 monoclonal antibody (antiCD3), and the disregulation in TH subsets of CD4+ T cells with a malfunction of TH1 cells and an expansion of TH2, might contribute to this situation. So, by using biotherapeutic treatments to allow the generation of productive immune response in these patients it is essential to identify the defect in their immune system to discover how these mechanisms should be appropriately manipulated in vivo to switch their immune response from a non-productive to a productive one. We have studied this in a group of patients and healthy subjects as the control group, performing their immunological evaluation by determining these parameters: serum levels of IL-2, interferon (IFN) gamma, IL-4, IL-6, IL-7, IL-8, tumour necrosis factor (TNF) alpha, soluble IL-2 receptor (sIL-2R), intercellular adhesion molecule 1 (sICAM-1) and CD30 (sCD30) molecules; PBMC phenotypic antigens expression (CD3, CD4, CD8, CD19, CD16, CD56, CD57, CD25) on peripheral blood mononuclear cells (PBMC); proliferative response of PBMC to IL-2, IL-4 and anti-CD3 monoclonal antibody (antiCD3). Moreover, since mutant c-Ki-ras oncogene is a very frequent finding in colorectal cancers and there are indications which suggest its involvement in tumour progression, the analysis of c-ki-ras codon 12 and 13 were determined and the statistical evaluation of the above immunological parameters were performed by comparing the patient groups with (M+) and without (M-) these mutations with each other, and with the healthy group. The results underline the necessity of biotherapeutic treatments inducing TH1 cell functions in these patients. Moreover in M+ it seems also important to solve the problem of the switch from B to macrophage cells as immune cells which present antigens, and the possible involvement of c-Ki-ras gene mutations in the impairment of T cell receptor activation (TCR).     

Prognostic value of serum biological markers in patients with hepatocellular carcinoma.

PURPOSE: Prognosis of patients with hepatocellular carcinoma (HCC) is assessed by using indexes based on clinical and instrumental parameters. The Cancer of the Liver Italian Program (CLIP) staging system combines the Child-Pugh classification with tumor size, portal invasion, and alpha-fetoprotein and predicts the outcome of HCC patients more precisely than the Okuda staging system. Serum levels of a number of biological variables have been found to be increased in patients with HCC and are associated with different outcomes. Our aims in this study were to test the prognostic role of the serum levels of soluble intercellular adhesion molecule-1 (sICAM-1), soluble interleukin-2 receptor (sIL-2R), interleukin 6 (IL-6), and anti-p53 and to assess whether the addition of any of the above serum markers could further improve the predictive ability of the CLIP score. EXPERIMENTAL DESIGN: Serum levels of sICAM-1, sIL-2R, IL-6, and anti-p53 were assayed in 80 patients with HCC and correlated with their outcomes. Nonparametric procedures were applied to test correlations between serum sICAM-1, sIL-2R, IL-6, anti-p53, and other prognostic factors. For survival analyses, the product-limit method, log-rank test, and Cox proportional hazards model were applied. RESULTS: Only serum levels of sIL-2R correlated with survival, which was longer for patients with lower values (< or =950 units/ml). However, with multivariate analysis sIL-2R did not confirm its predictive role when tested with the CLIP score as a covariate, with a hazard of death of 1.51 (95% confidence interval, 0.76-3.01). CONCLUSIONS: Serum levels of sICAM-1, sIL-2R, IL-6, and anti-p53 are not useful as prognostic factors for HCC in clinical practice. They do not improve the predictive ability of the CLIP score.     

大肠癌血清肿瘤坏死因子α、白细胞介素8和可溶性白细胞介素2受体水平的检测及其临床意义

目的探讨血清肿瘤坏死因子（TNFα）、白细胞介素8（IL-8）和可溶性白细胞介素2受体（sIL-2R）水平在结直肠癌中的意义。方法用酶联免疫吸附试验（ELISA）法测定93例结直肠癌患者和33例健康对照组外周静脉血清TNFα、IL-8和sIL-2R含量。结果结直肠癌患者血清TNFα、IL-8和sIL-2R含量明显高于正常对照组（P〈0．001）,Dukes分期C＋D期结肠癌患者血清TNFα,IL-8和sIL-2R含量明显高于DukesA＋B期（P〈0．001）,手术后3年复发者血清TNFα、IL-8和sIL-2R的含量均高于未复发组（P〈0．001）。结论TNFα、IL-8、sIL-2R是与结肠癌病情变化和预后相关的细胞因子,可作为结肠癌病情监测和预后判断的指标。     

Soluble immunological parameters and early prognosis of renal cell cancer patients

In local or metastatic cancer, a prognostic tumour marker could be a valuable tool in the selection of different treatments. In renal cell cancer (RCC) no such markers have been available. We therefore evaluated the association between several pretreatment serum markers, tumour classification and short term survival in RCC patients. Serum samples were collected before surgery and three months thereafter from 24 RCC patients. Interleukin-6 (IL-6), IL- 12, soluble IL-2 receptor (sIL-2R) and intercellular adhesion molecule-1 (sICAM-1) were measured in serum samples using specific commercial enzyme immunoassay kits. Serum IL-6, sIL-2R and sICAM-1 levels before nephrectomy were significantly higher in non-local tumours than in local ones (mean IL-6 53 pg/ml versus 6.3 pg/ml, and sICAM-1 443 ng/ml versus 290 ng/ml, sIL-2R 3779 pg/ml versus 1796 pg/ml). In contrast, IL-12 levels were higher in local tumours (148 versus 102 pg/ml) and the levels increased significantly (P < 0.005) after removal of the primary tumour in patients with local disease. All patients with local tumours had normal IL-6 values, while only one with a non-local tumour had IL-6 levels below 10 pg/ml. In addition, IL-6 and sICAM-1 levels before operation were significantly higher in patients with short (less than one year) survival (p=0.007 to IL-6 and p=0.006 to sICAM-1). In contrast, patients with shorter survival had significantly lower IL-12 (p=0.03) levels. Our findings suggest that RCC induces changes in several immunological parameters. These soluble immunological factors, IL-6, IL-12, sIL-2R and sICAM-1, might have a role as prognostic factors in RCC.     

Soluble interleukin-2 receptor, intercellular adhesion molecule-1 and interleukin-10 serum levels in patients with melanoma

Serum soluble interleukin-2 receptor (sIL-2R), intercellular adhesion molecule-1 (sICAM-1) and interleukin-10 (IL-10) have each been reported as useful markers for melanoma progression. To evaluate the clinical relevance of these three markers, we simultaneously analysed their serum levels in patients with melanoma. A longitudinal study with a 3-year follow-up was performed and different stages of the disease were considered. Mean values of sIL-2R were significantly higher than in normal controls in all stages and correlated with the disease progression. The prognosis of patients with levels > 529 U/ml of sIL-2R was significantly poorer than in patients with sIL-2R levels < 529 U/ml. Levels of sICAM-1 were also elevated in melanoma patients, specially at the time of the metastatic disease. Serum IL-10 levels were more frequently detectable in the patients that developed metastasis during follow-up, and the prognosis of patients with detectable IL-10 levels was significantly poorer than in those patients with IL-10 undetected levels. Statistical analysis based on Logistic and Cox regression models showed that only sex, stage and sIL-2R value are factors significantly associated with metastatic progression. Moreover, high levels of sIL-2R could be a risk factor for malignant progression in melanoma.     

大肠癌患者血清和组织中sIL-2R和sICAM-1水平的变化及意义

目的研究大肠癌血清和组织中sIL-2R和sICAM-1水平变化及意义。方法采用双抗体夹心ELISA法对44例大肠癌手术前后、28例大肠息肉、30例对照组血清sIL-2R和sICAM-1水平进行检测,并检测大肠癌及大肠息肉组织中两者水平。结果大肠癌组血清sIL-2R、sICAM-1水平分别为（209．27±127．42）pmol／L、（693．22±276．25）ng／ml,明显高于大肠息肉组和对照组。大肠癌组织中两者水平分别为（233．66±170．22）pmol／L、（706．92±286．09）ng／ml,明显高于大肠息肉组。大肠癌血清和组织中两者水平与Duke分期有关,与组织分化程度无关。大肠癌根治性手术后1个月血清两者水平明显下降,而姑息性手术下降不明显。结论血清和肿瘤组织中sIL-2R、sICAM-1水平变化可作为大肠癌诊断、手术方法选择、预后监测有意义的参考指标。     

Pretreatment serum markers and lymphocyte response to interleukin-2 therapy.

Lymphocytosis is a marker of subcutaneous interleukin (IL)-2 therapy efficacy, whereas baseline elevated inflammatory indices were noticed in IL-2-resistant disease. The aim of this study was to analyse the relationship between pretreatment circulating values of IL-6, neopterin, sIL-2R, ESR and the changes in lymphocyte number in response to IL-2 administration. Twenty metastatic renal cell cancer patients were treated with subcutaneous IL-2 immunotherapy (6 000 000 IU day(-1) for 6 days per week for 4 weeks); tumour response consisted of partial response (PR) in four patients, stable disease (SD) in eight patients and progressive disease (PD) in eight patients. Abnormally high pretreatment values of each marker were found as follows: IL-6 in seven patients, neopterin in nine patients, sIL-2R in 13 patients. In response to IL-2 immunotherapy, a significantly higher mean increase in lymphocyte number and a higher percentage of patients with tumour response or stable disease were observed when pretreatment values of IL-6, neopterin and sIL-2R were within the normal range, in comparison to patients with high values for these markers. The pretreatment excess of these serum inflammatory markers seems to negatively influence both the host and tumour response to IL-2 administration, by preventing the IL-2-induced lymphocytosis and resulting in tumour progression. Further studies are requested to verify if overall survival and quality of life may depend on pretreatment host immune status and/or lymphocyte response after IL-2 administration.     

IL-6 trans-signaling in formation and progression of malignant ascites in ovarian cancer

Classic signaling by the proinflammatory cytokine interleukin 6 (IL-6) involves its binding to target cells that express the membrane-bound IL-6 receptor α. However, an alternate signaling pathway exists in which soluble IL-6 receptor (sIL-6Rα) can bind IL-6 and activate target cells that lack mIL-6Rα, such as endothelial cells. This alternate pathway, also termed trans-signaling, serves as the major IL-6 signaling pathway in various pathologic proinflammatory conditions including cancer. Here we report that sIL-6Rα is elevated in malignant ascites from ovarian cancer patients, where it is associated with poor prognosis. IL-6 trans-signaling on endothelial cells prevented chemotherapy-induced apoptosis, induced endothelial hyperpermeability, and increased transendothelial migration of ovarian cancer cells. Selective blockade of the MAPK pathway with ERK inhibitor PD98059 reduced IL-6/sIL-6Rα-mediated endothelial hyperpermeability. ERK activation by the IL-6/sIL-6Rα complex increased endothelial integrity via Src kinase activation and Y685 phosphorylation of VE-cadherin. Selective targeting of IL-6 trans-signaling in vivo reduced ascites formation and enhanced the taxane sensitivity of intraperitoneal human ovarian tumor xenografts in mice. Collectively, our results show that increased levels of sIL-6Rα found in ovarian cancer ascites drive IL-6 trans-signaling on endothelial cells, thereby contributing to cancer progression. Selective blockade of IL-6 trans-signaling may offer a promising therapeutic strategy to improve the management of patients with advanced ovarian cancer.     

Serum soluble interleukin-2 receptor level as a prognostic indicator in gastric cancer.

T lymphocytes, activated by interleukin 2 during an anti-tumour response, release soluble interleukin 2 receptors (sIL-2R) into the bloodstream. We analysed the prognostic value of the serum sIL-2R level in gastric cancer. Serum concentration of sIL-2R in 96 gastric cancer patients and 100 healthy control subjects'' was measured by enzyme-linked immunosorbent assay. All survivors were followed for more than 50 months. Serum sIL-2R level was considered with respect to prognosis, clinicopathological factors, other tumour markers and peripheral blood cell count. Stage III and IV patients had significantly higher sIL-2R levels than lower stage patients and control subjects. Stage III and IV gastric cancer patients were divided into ''high'' and ''low'' slL-2R groups based upon the control subjects'' serum sIL-2R mean value plus one standard deviation. The high group had a significantly worse prognosis than the low group, although clinicopathological features and treatments were similar. Multivariate analysis demonstrated that the serum sIL-2R level is an independent indicator. The sIL-2R level did not correlate with carbohydrate antigen 19-9, however it did correlate with carcinoembryonic antigen (r = 0.22) and with numbers of peripheral blood monocytes (r = 0.54). In conclusion, serum sIL-2R may predict the outcome of gastric cancer patients with stage III or IV disease.     

大肠癌患者血清IAP、sIL-2R和IL-12变化

[目的]探讨检测血清IAP、sIL鄄2R和IL鄄12含量在大肠癌的辅助诊断、预后判断中的临床意义。[方法]采用单向免疫扩散法和ELISA法分别检测30例健康正常人及32例大肠癌患者手术前、后的血清IAP、sIL鄄2R和IL鄄12水平。[结果](1)大肠癌患者手术前血清IAP、sIL鄄2R水平均明显高于对照组(P<0.001和P<0.01),晚期组血清IAP、sIL鄄2R水平明显高于早期组(P<0.02和P<0.05),IAP与sIL鄄2R水平呈显著正相关(r=0.987,P<0.001);大肠癌患者血清IL鄄12水平明显低于对照组(P<0.05)。(2)串联IAP、sIL鄄2R两指标筛检大肠癌的敏感性为78.1%,特异性为93.33%,并联两指标筛检大肠癌,其敏感性为93.75%,特异性为73.3%。(3)手术后患者血清IAP、sIL鄄2R水平均明显低于手术前(P<0.001),早期组下降有明显差异性(P<0.001),而晚期组下降不明显(P>0.1);患者术后血清IL鄄12水平明显比术前升高(P<0.02),早期组上升显著(P<0.001),晚期组上升不明显(P>0.05)。[结论](1)检测患者血清IAP、sIL鄄2R水平对大肠癌的辅助诊断、病情判断、手术治疗和预后观察均有较高的临床价值。(2)联合检测血清IAP、sIL鄄2R对筛检大肠癌患者具有较高的敏感性。(3)血清IAP、sIL鄄2R和IL鄄12可作为指导大肠癌患者免疫学治疗较客观的指标。     

Interleukins, TNF-alpha and beta-2M in patients with B cell chronic lymphocytic leukemia

In order to investigate the possible existence of a prognostic factor for B cell chronic lymphocytic leukemia (B-CLL), we determined the serum levels of TNF-alpha, IL-1a, IL-1b, IL-2, sIL-2R, IL-6, IL-10 and beta-2M in 20 patients. We observed significant changes in sIL-2R and beta-2M levels, whereas in all stages of disease, TNF-alpha and other interleukins exhibited only mild changes. An excellent correlation between sIL-2R and beta-2M levels and disease activity wes reported. Patients with aggressive disease (Rai stages III and IV and Richter's syndrome) had increased levels. Patients who responded to therapy and with improved clinical status had decreased sIL-2R and beta-2M levels. However, patients with progressive disease and no response to therapy were associated with increased levels of sIL-2R and beta-2M. In conclusions, as serum levels of sIL-2R and beta-2M are increased in the aggressive stages of B-CLL, they may be used as reliable markers for monitoring B-CLL activity, showing response to treatment and early relapse and/or disease progression.     

Inflammatory biomarkers for persistent fatigue in breast cancer survivors.

PURPOSE: This study seeks to define immunologic and inflammatory variables associated with persistent post-treatment fatigue in breast cancer survivors. EXPERIMENTAL DESIGN: Leukocyte subsets, plasma inflammatory markers, and ex vivo proinflammatory cytokine production were assessed in 50 fatigued and nonfatigued breast cancer survivors recruited > or = 2 years after successful primary therapy. Multivariate statistical analyses were used to define a composite immunologic biomarker of fatigue risk. RESULTS: Fatigued breast cancer survivors were distinguished from nonfatigued survivors by increased ex vivo monocyte production of interleukin (IL)-6 and tumor necrosis factor-alpha following lipopolysaccharide stimulation, elevated plasma IL-1ra and soluble IL-6 receptor (sIL-6R/CD126), decreased monocyte cell-surface IL-6R, and decreased frequencies of activated T lymphocytes and myeloid dendritic cells in peripheral blood (all P < 0.05). An inverse correlation between sIL-6R and cell-surface IL-6R was consistent with inflammation-mediated shedding of IL-6R, and in vitro studies confirmed that proinflammatory cytokines induced such shedding. Multivariate linear discriminant function analysis identified two immunologic markers, the ratio of sIL-6R to monocyte-associated IL-6R and decreased circulating CD69+ T lymphocytes, as highly diagnostic of fatigue (P = 0.0005), with cross-validation estimates indicating 87% classification accuracy (sensitivity = 0.83; specificity = 0.83). CONCLUSION: These results extend links between fatigue and inflammatory markers to show a functional alteration in proinflammatory cytokine response to lipopolysaccharide and define a prognostic biomarker of behavioral fatigue.     

Effect of platelet activating factor and butyrate on the expression of interleukin-2 receptor alpha in nasopharyngeal carcinoma cells

Serum level of soluble interleukin-2 receptor alpha (sIL-2Ralpha) has been shown to correlate with disease progression and prognosis of cancer patients. However, the available information about the source and the pathophysiological regulation of IL-2Ralpha in cancer cells is limited. This study addressed the questions of prognostic value and the source of sIL-2Ralpha in patients with nasopharyngeal carcinoma (NPC). Biological regulation of IL-2Ralpha was characterized in NPC cell lines. Serum sIL-2Ralpha levels of 113 NPC patients were measured by enzyme-linked immunosorbent assay (ELISA). Levels of sIL-2Ralpha in NPC patients were significantly higher than that in the healthy controls, and sIL-2Ralpha levels were correlated with disease progression and patient survival. IL-2Ralpha was identified in cancer cells by immunocytochemistry. In vitro, IL-2Ralpha expression was markedly increased following treatment with platelet activating factor and/or n-sodium butyrate. Increased secretion of IL-2Ralpha was also detected in the culture media. The secreted IL-2Ralpha could functionally bind IL-2. These results indicate that elevated sIL-2Ralpha was often detected in patients with advanced NPC. The elevated sIL-2Ralpha could be shed from NPC cells by a yet to be determined mechanism and IL-2Ralpha expression in NPC cells could be upregulated by platelet activating factor and butyrate.     

Mesothelin overexpression promotes autocrine IL-6/sIL-6R trans-signaling to stimulate pancreatic cancer cell proliferation

Mesothelin (MSLN) overexpression in pancreatic cancer (PC) leads to enhanced cell survival/proliferation and tumor progression. After screening for a number of growth factors/cytokines, we found that the MSLN expression correlated closely with interleukin (IL)-6 in human PC specimens and cell lines. Stably overexpressing MSLN in different PC cell lines (MIA-MSLN and Panc1-MSLN) led to higher IL-6 production. Silencing MSLN by small interfering RNA (siRNA) significantly reduced IL-6 levels. Blocking the observed constitutive activation of nuclear factor-kappaB (NF-κB) with IKK inhibitor wedelolactone in MIA-MSLN cells also reduced IL-6. Silencing IL-6 by siRNA reduced cell proliferation, cell cycle progression and induced apoptosis with significant decrease of c-myc/bcl-2. Interestingly, recombinant IL-6-induced proliferation of MIA-MSLN cells but not MIA-V cells. Although messenger RNA/protein levels of IL-6R did not vary, soluble IL-6R (sIL-6R) was significantly elevated in MIA-MSLN and was reduced by treatment with the TACE/ADAM17 inhibitor TAPI-1, indicating intramembrane IL-6R cleavage and IL-6 trans-signaling may be operative in MIA-MSLN cells. Blocking the IL-6/sIL-6R axis using sIL-6R antibody abrogated basal proliferation/survival as well as recombinant human IL-6-induced cell proliferation. Our data suggest that MSLN-activated NF-κB induces elevated IL-6 expression, which acts as a growth factor to support PC cell survival/proliferation through a novel auto/paracrine IL-6/sIL-6R trans-signaling. In addition, using a panel of PC cells with varying MSLN/IL-6 expressions, we showed that MSLN/IL-6 axis is a major survival axis in PC supporting tumor cell growth under anchorage-dependent and independent conditions. The close correlation between MSLN and IL-6 provides a new rationale for combination therapy for effective control of MSLN-overexpressing PCs.