Increased interleukin-10 serum levels in patients with solid tumours

Serum Th1 and Th2 cytokine balance in patients of superficial transitional cell carcinoma of bladder pre- and post-intravesical combination immunotherapy

Combination therapy with intravesical bacillus Calmette-Guerin (BCG) plus interferon-alpha2b (IFN-alpha2b) for superficial transitional cell carcinoma (TCC) seems to be immune-dependent and activation of Th1 immune response is required for clinical efficacy. The present study evaluates circulating serum cytokine profiles (Th1/Th2 cytokines IFN-gamma, IL-2 TNF-alpha, IL-4, IL-6 and IL-10) in 41 bladder cancer patients prior to transurethral resection of tumor (TURBT) (pre-therapy), and following intravesical combination immunotherapy (post-therapy) and their association with recurrence. Mean levels of IL-2 and TNF-alpha were significantly reduced while IL-4, IL-6 and IL-10 were significantly enhanced in pre-therapy samples as compared to controls. Mean levels of IFN-gamma, IL-2 and TNF-alpha were significantly increased while IL-4 and IL-10 were significantly reduced in patients after instillation of combination immunotherapy. These findings suggest that bladder cancer patients develop Th2 dominant status with deficient type 1 immune response that shows tendency to reversal following therapy.

Association of genetic polymorphisms in the interleukin-10 promoter with risk of prostate cancer in Chinese

Background

Recent studies identified an increased risk of prostate cancer (PCa) in Caucasian men harboring polymorphisms of genes involved in innate immunity and inflammation. This study was designed to assess whether single nucleotide polymorphisms in the IL-10 promoter play a role in predisposing individuals to PCa in a Chinese population.

Methods

We genotyped three SNPs of the IL-10 promoter (-1082A/G, -819T/C and -592A/C) using polymerase chain reaction-restriction fragment length polymorphism analysis in 262 subjects with PCa and 270 age-matched healthy controls. Odds ratio and 95% confidence interval were determined by logistic regression for the associations between IL-10 genotypes and haplotypes with the risk of PCa and advanced PCa grade.

Results

No significant differences in allele frequency or genotype distribution were observed for any of the IL-10 SNPs between PCa patients and control subjects. Significantly higher frequencies of -1082G, -819C and -592C allele and GCC haplotype were observed, however, in early stage patients in comparison to advanced PCa patients (for -1082 G, 13.9% vs 6.1%, OR = 2.48, P = 0.005; for -819 C 40.3% vs 30.8%, OR = 1.51, P = 0.043; for -512C, 40.3% vs 30.8%, OR = 1.51, P = 0.043; and for haplotype GCC 11.1%vs 5.1%, OR = 2.66, P = 0.008, respectively).

Conclusions

Our results identify that IL-10 promoter polymorphisms might not be a risk factor for PCa in Chinese cohorts, but rather incidence of polymorphisms associates with PCa grade, suggesting that IL-10 expression may impact PCa progression.

Interleukin-10 production by tumor infiltrating macrophages plays a role in Human Papillomavirus 16 tumor growth

BACKGROUND

Human Papillomavirus, HPV, is the main etiological factor for cervical cancer. Different studies show that in women infected with HPV there is a positive correlation between lesion grade and number of infiltrating macrophages, as well as with IL-10 higher expression. Using a HPV16 associated tumor model in mice, TC-1, our laboratory has demonstrated that tumor infiltrating macrophages are M2-like, induce T cell regulatory phenotype and play an important role in tumor growth. M2 macrophages secrete several cytokines, among them IL-10, which has been shown to play a role in T cell suppression by tumor macrophages in other tumor models. In this work, we sought to establish if IL-10 is part of the mechanism by which HPV tumor associated macrophages induce T cell regulatory phenotype, inhibiting anti-tumor activity and facilitating tumor growth.

RESULTS

TC-1 tumor cells do not express or respond to IL-10, but recruit leukocytes which, within the tumor environment, produce this cytokine. Using IL-10 deficient mice or blocking IL-10 signaling with neutralizing antibodies, we observed a significant reduction in tumor growth, an increase in tumor infiltration by HPV16 E7 specific CD8 lymphocytes, including a population positive for Granzyme B and Perforin expression, and a decrease in the percentage of HPV specific regulatory T cells in the lymph nodes.

CONCLUSIONS

Our data shows that in the HPV16 TC-1 tumor mouse model, IL-10 produced by tumor macrophages induce regulatory phenotype on T cells, an immune escape mechanism that facilitates tumor growth. Our results point to a possible mechanism behind the epidemiologic data that correlates higher IL-10 expression with risk of cervical cancer development in HPV infected women.

Natural killer cell cytotoxicity and immunosuppressive cytokines (IL-10, TGF-beta1) in patients with gastric cancer

Cytotoxic activity of NK cells was estimated as related to IL-10 and TGF-beta1 serum levels and Helicobacter pylori infection in gastric cancer patients. Moreover, we sought to determine whether human gastric adenocarcinoma cells in vitro release IL-10, TGF-beta1 or factor(s) affecting NK cytotoxicity. The studies were conducted on 42 patients with gastric cancer (14 with I-II stage-group 1; 28 with III-IV stage-group 2) and on 20 healthy volunteers. The cytotoxicity was tested on NK cells isolated from peripheral blood. IL-10 and TGF-beta1 levels were determined by ELISA. H. pylori was detected in cultures of gastric mucosa biopsies and in direct preparations. In 71.4% patients of group 1 NK cytotoxicity and IL-10 serum levels remained within a normal range while in 68% patients of group 2 a marked decrease was noted in cytotoxic function of NK cells, accompanied by increased levels of IL-10 in serum. In turn, in most patients of either group, independently of NK cytotoxicity and stage grouping in the patients, elevated serum levels of TGF-beta1 were detected. Presence of H. pylori infection manifested no relationship with NK cytotoxicity, IL-10, or the TGF-beta1 serum levels. In cultures of tumour cells presence of IL-10 and TGF-beta1 was demonstrated. Nevertheless, supernatants of the cultures did not change cytotoxic activity of NK cells. Development of gastric carcinoma is accompanied by markedly decreased cytotoxic function of NK cells and by elevated IL-10 and TGF-beta1 serum levels. Gastric carcinoma cells may release IL-10, the suppressive activity of which may in a secondary manner decrease NK cytotoxicity.

Low level exposure to monomethyl arsonous acid-induced the over-production of inflammation-related cytokines and the activation of cell signals associated with tumor progression in a urothelial cell model

Human bladder cancer has been associated with chronic exposure to arsenic. Chronic exposure of an immortalized non-tumorigenic urothelial cell line (UROtsa cells) to arsenicals has transformed these cells to a malignant phenotype, but the involved mechanisms are not fully understood. Chronic inflammation has been linked with cancer development mainly because many pro-inflammatory cytokines, growth factors as well as angiogenic chemokines have been found in tumors. In this study the chronology of inflammatory cytokines production was profiled in UROtsa cells chronically exposed to the toxic arsenic metabolite, monomethylarsonous acid [50 nM MMA(III)] to know the role of inflammation in cell transformation. Acute 50 nM MMA(III) exposure induced over-production of many pro-inflammatory cytokines as soon as 12 h after acute exposure. The same cytokines remain over-regulated after chronic exposure to 50 nM MMA(III), especially after 3 mo exposure. At 3 mo exposure the sustained production of cytokines like IL-1, IL-6, IL-8 and TNF is coincident with the appearance of characteristics associated with cell transformation seen in other arsenic-UROtsa studies. The sustained and increased activation of NFkappaB and c-Jun is also present along the transformation process and the phosphorylated proteins p38 MAPK and ERK 1/2 are increased also through the time line. Taken together these results support the notion that chronic inflammation is associated within MMA(III)-induced cell transformation and may act as a promoting factor in UROtsa cell transformation.

Dysfunction of natural killer cells in patients with transitional cell carcinoma

Previous studies had established that transforming growth factor-beta1 (TGF-beta1) is highly expressed in bladder tumor, facilitating progression and spreading of the cancerous cells. Here, we report that both the number and the cytotoxic function of natural killer (NK) cells are decreased in patients with superficial transitional cell carcinoma (TCC). In consistent with previously reported findings, the plasma TGF-beta1 concentration is also elevated in patients with superficial TCC. In vitro, the cytotoxic function of NK cells was impaired by the presence of TGF-beta1. Hence, our data suggested elevated concentration of serum TGF-beta1 in loss of NK cytotoxicity in superficial TCC patients, implicating altered innate immunity may correlate with the incidence of TCC.

Serum interleukin-6 and -10 levels in patients with gastric cancer

BACKGROUND

Interleukin-6 (IL-6) is known to be a multifunctional cytokine and IL-10 is an immunosuppressive factor. Both have been reported to be related to the disease prognosis in some human solid tumors. In the present study, we evaluated the clinical significance of preoperative serum IL-6 and IL-10 levels as new tumor markers in patients with gastric cancer (GC).

METHODS

Preoperative serum samples from 90 patients with GC and 9 normal healthy volunteers were assayed. Levels of IL-6 and IL-10 were determined by enzyme-linked immunosorbent assay (ELISA). The clinical significance of serum IL-6 and IL-10 levels was evaluated and compared with serum carcinoembryonic antigen (CEA) levels and serum C-reactive protein (CRP) levels in these patients.

RESULTS

The serum level of IL-6 was significantly higher in the GC patients than in the healthy subjects. Serum IL-6 levels were strongly correlated with CRP levels, but did not correlate with CEA or carbohydrate antigen (CA) 19-9 levels. Serum IL-10 levels did not correlate with CEA, CA19-9, or CRP. Strong positive correlations between serum IL-6 levels and tumor size and tumor stage were observed. On the other hand, IL-10 did not correlate with such clinicopathological findings of tumors. However, high serum IL-10 levels were associated with a worse prognosis in the GC patients, independently of their tumor stage.

CONCLUSION

These findings indicate that serum IL-6 may suggest gastric cancer progression. On the other hand, IL-10 may play an important role in host immunity and the prognosis of GC patients.

IL-10 -1082 G>A: a risk for prostate cancer but may be protective against progression of prostate cancer in North Indian cohort

BACKGROUND

Chronic intraprostatic inflammation is suspected to play a major role in the pathogenesis of prostate cancer (PCa). Polymorphisms in interleukin-10 (IL-10), a key anti-inflammatory cytokine gene can influence immune response and immune evasion of tumor cells. Its role as an anti-metastatic molecule is also well documented.

METHODS

Gene promoter polymorphisms in IL-10 (-1082 G>A and -819 C>T) was analyzed in 159 PCa patients and 259 healthy controls to investigate their potential association with susceptibility for PCa.

RESULTS

Our results indicated that the heterozygous (GA) and homozygous mutant (AA) genotypes of IL-10 -1082 to be more prevalent among PCa patients in comparison to controls (GA: OR - 2.8, p = 0.011; AA: OR - 2.3, p = 0.037). More patients (92.5%) than controls (82.7%) were positive for the A allele (GA + AA: OR - 2.6, p = 0.015). We observed lower frequency of T(-819)-G(-1082) haplotype in patients without bone metastasis (4.4%, OR - 0.30, p = 0.019) in comparison to PCa patients with bone metastasis (12.6%).

CONCLUSION

Our results support the emerging hypothesis that genetically determined immune activity may play a role in the pathophysiology of PCa. Our findings of high producer of IL-10 -1082 variants suggest initiation of PCa. Future studies in large cohort of different ethnicity PCa groups are warranted to establish definite associations with other cytokine gene polymorphisms.

Genetic association of cytokine DNA polymorphisms with head and neck cancer

Mutations in oncogenes or tumor suppressor genes, as well as environmental factors such as tobacco chewing or smoking, poor oral hygiene, ill-fitting dental appliances, infection by certain HPV types, or alcohol abuse, seem to be involved in the multifactorial process of carcinogenesis in head and neck. Recently, several genetic association studies have indicated that common DNA polymorphisms in low penetrance genes may affect the susceptibility of an individual to malignancy. Cytokines are an important group of proteins that regulate and mediate inflammation and angiogenesis. Tumor growth, invasion and metastasis are facilitated when there is a deregulation in their production. Cytokines include interleukins (ILs), tumor necrosis factors (TNFs) and certain growth factors (GFs). A number of genetic association studies have recently investigated the putative correlation between functional DNA polymorphisms in cytokine genes and head and neck carcinomas. This review discusses the findings of such studies in oral, nasopharyngeal and esophageal squamous cell carcinomas. Extensive research has indicated that functional polymorphisms affecting gene expression of IL-4,-6,-8,-10 as well as TNF-alpha are strongly associated with increased risk for oral cancer. Gene expression of TNF-alpha seems to be associated also with esophageal carcinomas, while for nasopharyngeal cancer the picture is yet unclear. It is generally believed that such genetic association studies will gradually increase our knowledge regarding the predisposed manifestation and advancement of these malignancies in the head and neck region.

The involvement of IL-10, IL-6, IFN-gamma, TNF-alpha and TGF-beta gene polymorphisms among Turkish lung cancer patients

Several genes encoding different cytokines may play crucial roles in host susceptibility to lung cancer, since cytokine production capacity varies among individuals and depends on cytokine gene polymorphisms. The association between cytokine gene polymorphisms with primary lung carcinoma was investigated. DNA samples were obtained from a Turkish population of 44 patients with primary lung cancer, and 59 healthy control subjects. All genotyping (IFN-gamma, TGF-beta1, TNF-alpha, IL-6 and IL-10) experiments were performed using sequence-specific primers (SSP)-PCR. When compared to the healthy controls, the frequencies of high/intermediate producing genotypes of IL-10 and low producing genotype of TNF-alpha were significantly more common in the patient group. It is noteworthy that lung cancer patients with the TGF-beta T/T genotype in codon 10 had statistically longer survival compared to those having the C/C genotype (Kaplan-Meier survival function test, log rank significance = 0.014). These results suggest that IL-10, TNF-alpha and TGF-beta1 gene polymorphisms may affect host susceptibility to lung cancer and the outcome of the patients.

Long-term interleukin-10 presence induces the development of a novel, monocyte-derived cell type

Interleukin (IL)-10 is one of the most crucial immunoregulatory cytokines. Its short-term effects have been analysed extensively, but little is known about its long-term effects. This is of considerable importance, as high systemic IL-10 levels are present for long periods in patients with persistent viral infections, certain cancers and in critical care patients. Our study investigated the effects of the long-term presence of IL-10 on human peripheral blood monocytes. In vitro, IL-10 treatment of these cells for 7 days induced the development of a novel cell type characterized by unique phenotypical and functional characteristics. These cells showed high HLA-DR expression and low expression of CD86 and other co-stimulatory molecules on their surface. The mRNA levels of both HLA-DR and CD86 were high, but no intracellular accumulation of CD86 protein was observed. With respect to its function, these cells showed strongly diminished tumour necrosis factor-alpha production following lipopolysaccharide stimulation, strongly diminished allogenic CD4(+) T cell stimulatory capacity, and even induced a hyporesponsive state in CD4(+) T cells. The phenotype remained stable despite the removal of IL-10. In vivo, we found monocytic cells from patients exhibiting this phenotype after long-term IL-10 exposure. These results complement our knowledge further about the biological effects of IL-10 and may provide an explanation for the sustained immunodeficiency in cases of the persistent presence of systemic IL-10.

Monocyte-derived IL-10 expression predicts prognosis of stage IV melanoma patients

There are no standard methods to predict response to treatment or outcome of stage IV melanoma. Our previous assessment of peripheral blood mononuclear cells (PBMC) from immunized patients demonstrated that interleukin (IL)-10 expression might be associated with prognosis. However, PBMC are a mixture of CD4+ cells, CD8+ cells, and monocytes. This study identified the subset of PBMC responsible for IL-10 expression and evaluated the prognostic value of IL-10 expression in immunized stage IV patients. Eighty-seven patients with stage IV melanoma were randomly selected from our database. All patients had received an allogeneic melanoma whole-cell vaccine (Canvaxin) after complete resection of clinical disease. Blood samples had been collected serially during Canvaxin administration and cryopreserved. Intracellular IL-10 expression was assessed by double staining fluorescence-activated cell sorter. CD14+ monocytes are the predominant PBMC producing IL-10. Sixteen weeks after treatment (week 16), IL-10 levels were significantly (P=0.02) higher in poor-survival patients than those with favorable outcomes. Patients were separated into 2 groups on the basis of the CD14+ monocyte IL-10 response: either increasing or decreasing IL-10 expression from preimmunization (week 0) to week 16 blood draws. Patients with increasing IL-10 levels had significantly shorter survival than those whose IL-10 levels decreased at week 16 (P<0.0001). Multivariate analysis demonstrated that trends in IL-10 levels inversely correlated with survival (P<0.0001). We conclude that CD14+ monocytes are the dominant cellular source of IL-10 among PBMC and that changes in IL-10 expression may serve as an immunologic-based surrogate for predicting outcome for stage IV patients after surgical resection.

Immunology and immunotherapy approaches for prostate cancer

Several mechanisms that impair the immune response to promote tumour progression are reported. These mechanisms aim to reduce the ability of antigen-presenting cells to present antigen and activate naïve T cells to support an active immune response or to create a suppressive environment that induce non-functional tumour-associated antigen-specific T cells. Prostate cancer (PC) alone accounts for 33% of incident cancer cases and about 9% of all cancer-related deaths among men in the USA during 2006. Whereas androgen deprivation has remained the first line of therapy for advanced PC, other therapies are still required due to progression to an androgen-resistant state and eventually loss of control in patients receiving hormonal therapy. Immunotherapy seems to be a promising approach to enhance tumour-specific T-cell responses in different cancers including prostate. More importantly, clinical trials in advanced PC patients have shown that immunotherapy may generate significant clinical responses. Immunology and immunotherapy aspects of PC with focus on prostate-specific antigen will be presented.

Human interleukin 24 (MDA-7/IL-24) protein kills breast cancer cells via the IL-20 receptor and is antagonized by IL-10

The melanoma differentiation-associated gene-7 (mda-7/IL-24) is a unique member of the interleukin 10 (IL-10) family of cytokines, with ubiquitous tumor cell pro-apoptotic activity. Recent data have shown that IL-24 is secreted as a glycosylated protein and functions as a pro-Th1 cytokine and as a potent anti-angiogenic molecule. In this study, we analyzed the activity of Ad-mda7 and its protein product, secreted IL-24, against human breast cancer cells. We show that Ad-mda7 transduction of human breast cancer cells results in G(2)/M phase cell cycle arrest and apoptotic cell death, which correlates with secretion of IL-24 protein. Neutralizing antibody against IL-24 significantly inhibited Ad-mda7 cytotoxicity. IL-24 and IL-10 both engage their cognate receptors on breast cancer cells resulting in phosphorylation and activation of STAT3, however, IL-10 receptor binding failed to induce cell killing, indicating that tumor cell killing by IL-24 is independent of STAT3 phosphorylation. Treatment with exogenous IL-24 induced apoptosis in breast cancer cells and this effect was abolished by addition of anti-IL-24 antibody or anti-IL-20R1, indicating that bystander cell killing is mediated via IL-24 binding to the IL-20R1/IL-20R2 heterodimeric receptor complex. Co-administration of the related cytokine IL-10 inhibited killing mediated by IL-24 and concomitantly inhibited IL-24 mediated up-regulation of the tumor suppressor proteins, p53 and p27(Kip1). In summary, we have defined a tumor-selective cytotoxic bystander role for secreted IL-24 protein and identified a novel receptor-mediated death pathway in breast cancer cells, wherein the related cytokines IL-24 and IL-10 exhibit antagonistic activity.

Novel Involvement of the Immunomodulator AS101 in IL-10 Signaling, via the Tyrosine Kinase Fer

Interleukin-10 (IL-10) plays a major proliferative role in many tumors, and activates the transcription factor Stat3 by tyrosine phosphorylation. The immunomodulator ammonium trichloro (dioxoethylene-o,o') tellurate (AS101) has a direct antitumor activity, and is able to sensitize several tumors to chemotherapy, by inhibiting the tumor IL-10 autocrine loop. The tyrosine kinase Fer is essential for the proliferation of numerous malignant cell lines and in some cases was related to Stat3 activation. This article examined the role of AS101 in IL-10 signaling, and the correlation between Fer and Stat3, in human peripheral blood mononuclear cells (PBMC). We show that Fer was associated with Stat3 in PBMC and RAW 264.7, a macrophage cell line. Recombinant IL-10 (rIL-10) increased the tyrosine phosphorylation of Stat3, upregulated the levels of Fer, and increased the association of Fer with phosphorylated Stat3 (pYStat3). All the activities of IL-10 mentioned above were reversed by AS101. The effects conferred by AS101 were totally abolished by exogenous addition of rIL-10. These results indicate that AS101 downregulates the Stat3 IL-10 loop, and inhibits Fer association with pYStat3. We conclude that anti-IL-10 treatment using AS101, may be beneficial in certain malignancies and other pathologies in which IL-10 secretion is elevated and Stat3 is continuously phosphorylated.

Evaluation of interleukin-6, interleukin-10 and human hepatocyte growth factor as tumor markers for hepatocellular carcinoma

AIM

Serum alpha-fetoprotein (AFP) is the most important tumor marker for hepatocellular carcinoma (HCC). Previous reports indicated that HCC was also associated with increased levels of interleukin (IL)-6, IL-10 and hepatocyte growth factor (HGF). This study investigated the role of these cytokines as tumor markers for HCC.

METHOD

A total of 128 adults were prospectively enrolled and categorized into four groups: normal subjects (n=29), chronic hepatitis B or C (n=50), non-HCC tumors (n=23) and HCC (n=26). Serum AFP, IL-6, IL-10 and HGF levels were determined in all subjects.

RESULTS

The expression of IL-6 or IL-10 (> or =3 pg/ml), or high level of HGF (>1000 pg/ml) or AFP (>20 ng/ml) was observed in only 0-3% of normal subjects. Patients with HCC more frequently had higher IL-6 and IL-10 levels (p<0.05), whereas HGF levels in HCC patients were not significantly elevated compared to patients with chronic hepatitis or non-HCC tumors. Among patients with low (<20 ng/ml) AFP level, IL-6 or IL-10 expression was significantly associated with the existence of HCC (p<0.05). Patients with large (>5 cm) HCC more often had increased IL-6, IL-10 or AFP levels (p values all <0.05).

CONCLUSIONS

Serum levels of IL-6 and IL-10 are frequently elevated in patients with HCC but not in benign liver disease or non-HCC tumors. IL-6 and IL-10 may help identify a subset of HCC patients with low AFP level, and may serve as complementary tumor markers in these patients.

Cytokine Gene Polymorphisms and Breast Cancer Susceptibility

Human breast cancer (BC) is characterized by a considerable clinical heterogeneity. Steroid hormone receptor expression and growth factor receptor expression have been considered suitable diagnostic and prognostic markers, whereas mutations of oncosuppressor and gatekeeper genes have been found associated with an increased risk for this malignancy. To evaluate the role that polymorphisms of genes involved in the regulation of inflammatory response might play in BC susceptibility, we investigated associations between cytokine functionally relevant polymorphisms in 84 BC patients compared to 110 age- and sex-matched controls. TNF-alpha (-308G/A), TGF-beta1 (+869C/T), IL-10 (-1117G/A; -854C/T; -627C/A), and IFN-gamma (874T/A) single nucleotide polymorphisms (SNPs) were identified by sequence-specific primers (SSP)-PCR or restriction fragment length polymorphism (RFLP)-PCR. Genotype or haplotype distributions for each polymorphisms were consistent with the HWE in these populations. We were unable to demonstrate differences in genotype or allele frequencies between patient and control groups. Data obtained in this study indicate that none of the cytokine SNPs studied is likely to have predisposing or protective effects on BC susceptibility. On the other hand, both positive and negative association with BC have been reported for some of the studied genotypes by different research groups. In conclusion, further studies involving larger numbers of subjects are required.

Cytokine expression profile in human pancreatic carcinoma cells and in surgical specimens: implications for survival

Cytokine shedding by tumor cells into the local microenvironment modulates host immune response, tumor growth, and metastasis. The study aimed to verify the hypothesis that the immunological microenvironment of pancreatic carcinoma exists in a prevalently immunosuppressive state, influencing survival. We analyzed expression profiles of pro-inflammatory (IL-1beta, IL-2, IL-6, IL-8, IL-12 p40, IL-18 and IFN-gamma) and anti-inflammatory (IL-10, IL-11, IL-13 and TGF-beta isoforms) cytokines. The study was performed both in vitro, in five pancreatic carcinoma cell lines (real time RT-PCR), and in specimens from 65 patients, comparing tumoral versus non-tumoral pancreatic tissues (real time RT-PCR and immunohistochemistry). Furthermore, cytokines were measured in supernatants and sera (from patients and controls) by ELISA. All cell lines expressed IL-8, IL-18, TGF-beta1, TGF-beta2 and TGF-beta3, but not IFN-gamma and IL-2 transcripts. Expression of IL-1beta, IL-6, IL-10, IL-11, IL-13 and IL-12 mRNA was variable. All the above cytokines were detected as soluble proteins in supernatants, except IL-13. Tumor tissues overexpressed IL-1beta, IL-6, IL-8, IL-10, IL-11, IL-12 p40, IL-18, IFN-gamma, TGF-beta1, TGF-beta2 and TGF-beta3 at the mRNA level and IL-1beta, IL-18, TGF-beta2 and TGF-beta3 also at the protein level. Conversely, non-tumor tissues had stronger RNA and protein expression of IL-13. Survival was significantly longer in patients with high IL-1beta and IL-11 and moderate IL-12 expression. Serum IL-8, IL-10, IL-12, IL-18, TGF-beta1 and TGF-beta2 were higher in patients than in controls, as opposed to IL-1beta and IL-13. Patients with low circulating levels of IL-6, IL-18 and TGF-beta2 survived longer. Pancreatic cancer is characterized by peculiar cytokine expression patterns, associated with different survival probabilities.

[Prospective study of the levels of serum cytokines in patients with melanoma: prognostic value]

INTRODUCTION

The production of cytokines plays a primordial role in the immune systems fight against tumors. Therefore, we proposed to investigate whether the serum levels of different types of cytokines in melanoma patients were associated with the evolution of their disease.

MATERIAL AND METHODS

We analyzed the variation in the serum levels of cytokines representative of the Th1 (INFg and IL-15) and Th2 (IL-6 and IL-10) phenotypes in 33 patients with primary cutaneous melanoma. Peripheral blood samples were obtained every six months until we had a total of 4 samples per patient.

RESULTS

After 30 months, 29 patients (87.9 %) had survived with no signs of recurrence. Basal IL-10 serum levels were higher in the group of patients who expired than in the survivors. Among the patients who expired, an increase in IL-6 serum levels was observed in the last sample. No relationship could be proven between INFg and IL-15 levels and melanoma progression.

CONCLUSION

Determining the levels of type Th2 cytokines (IL-6 and IL-10) in the serum of melanoma patients could be useful in the clinical follow-up of these patients and serve as a predictive factor for the progression of the disease, with the prognosis being worse for patients with high IL-10 and IL-6 levels. On the other hand, determining the serum levels of type Th1 cytokines (IL-15 and INFg) does not seem to be as useful in predicting the prognosis.

The cancer stem cell: evidence for its origin as an injured autoreactive T cell

This review explores similarities between lymphocytes and cancer cells, and proposes a new model for the genesis of human cancer. We suggest that the development of cancer requires infection(s) during which antigenic determinants from pathogens mimicking self-antigens are co-presented to the immune system, leading to breaking T cell tolerance. Some level of autoimmunity is normal and necessary for effective pathogen eradication. However, autoreactive T cells must be eliminated by apoptosis when the immune response is terminated. Apoptosis can be deficient in the event of a weakened immune system, the causes of which are multifactorial. Some autoreactive T cells suffer genomic damage in this process, but manage to survive. The resulting cancer stem cell still retains some functions of an inflammatory T cell, so it seeks out sites of inflammation inside the body. Due to its defective constitutive production of inflammatory cytokines and other growth factors, a stroma is built at the site of inflammation similar to the temporary stroma built during wound healing. The cancer cells grow inside this stroma, forming a tumor that provides their vascular supply and protects them from cellular immune response.

As cancer stem cells have plasticity comparable to normal stem cells, interactions with surrounding normal tissues cause them to give rise to all the various types of cancers, resembling differentiated tissue types. Metastases form at an advanced stage of the disease, with the proliferation of sites of inflammation inside the body following a similar mechanism. Immunosuppressive cancer therapies inadvertently re-invigorate pathogenic microorganisms and parasitic infections common to cancer, leading to a vicious circle of infection, autoimmunity and malignancy that ultimately dooms cancer patients. Based on this new understanding, we recommend a systemic approach to the development of cancer therapies that supports rather than antagonizes the immune system.

Differences in immune cells engaged in cell-mediated immunity after chemotherapy for far advanced pancreatic cancer

OBJECTIVES

Little is known about the effects of chemotherapy on the immunity of cancer patient or the ideal timing for immunotherapy combined with chemotherapy. To address these questions, we evaluated the effect of gemcitabine and cisplatin combination chemotherapy on the immunity of pancreatic cancer patients.

METHODS

Thirteen patients with far advanced pancreatic cancer were enrolled and 7 sex- and age-matched healthy volunteers were included as a control group.

RESULTS

Compared with healthy controls, the amounts of peripheral blood mononuclear cells, dendritic cells (DCs), natural killer cells, CD4, and CD8 T cells were reduced. With this numerical suppression, NK cell cytotoxicity to K562 leukemia cells was also significantly impaired (7.7% +/- 4.9% versus 21.7% +/- 7.9% of DNA loss; P = 0.016). Serum concentrations of VEGF and interleukin-10 (IL-10) were higher than the control group (192.1 +/- 114.7 versus 50.8 +/- 39.5 pg/mL of vascular endothelial growth factor (VEGF) and 122 +/- 68.9 versus 111.4 +/- 37.4 pg/mL of IL-10). After 1 cycle of gemcitabine and cisplatin chemotherapy, the impaired immunity of patients with pancreatic cancer was restored. Specifically, the recovery of DCs occurred rapidly and exceeded the value of healthy controls. Levels of the immunosuppressive cytokines, IL-10 and VEGF, gradually decreased during chemotherapy.

CONCLUSIONS

Systemic chemotherapy seems to be beneficial for restoring the impaired immunity of patients with pancreatic cancer, and one of the ideal times to collect DCs for immunotherapy is after completing each cycle of chemotherapy.

The involvement of genetic polymorphism of IL-10 promoter in non-small cell lung cancer

STUDY OBJECTIVES

Interleukin-10 (IL-10) is mainly an anti-inflammatory cytokine produced by a number of cells including normal and neoplastic cells and has been implicated in autoimmunity, transplantation tolerance and tumorigenesis. Inter-individual variations in IL-10 production were genetically contributed to polymorphisms within IL-10 promoter region. The aim of this study was to determine whether polymorphisms in the IL-10 gene promoter were involved in predisposing an individual to non-small cell lung cancer (NSCLC).

PATIENTS

A total of 154 patients with non-small cell lung cancer were recruited into this study, together with 205 age- and gender-matched healthy smokers acting as control subjects.

MEASUREMENTS

Polymorphisms of sites within the promoter region of IL-10 gene were analyzed using polymerase chain reaction-restriction fragment length polymorphism technique on genomic DNA isolated from peripheral lymphocytes. The validity of this technique was proven by direct sequencing of polymerase chain reaction products. Statistical analyses were conducted to explore the contribution of polymorphism of IL-10 promoter to the susceptibility to NSCLC.

RESULTS

The distribution frequencies of genotypes of IL-10-1082, -819 and -592 were significantly different between NSCLC patients and controls. Pearson chi2 analysis showed that the frequency for IL-10-1082 G allele, IL-10-819C allele and IL-10-592C allele was independently higher in NSCLC patient group than that in the control group. Higher odds ratios (ORs) for NSCLC were seen for individuals with G allele of IL-10-1082 [OR=5.26, 95% CI 2.65-10.4, p<0.0001], C allele of IL-10-819 [OR=1.57, 95% CI 1.15-2.16, p=0.005], C allele of IL-10-592 [OR=1.59, 95% CI 1.15-2.19, p=0.005].

CONCLUSION

The polymorphisms of IL-10 genes were significantly associated with the occurrence of NSCLC.

Interleukin-10 -1082 promoter polymorphism is not associated with susceptibility to esophageal squamous cell carcinoma and gastric cardiac adenocarcinoma in a population of high-incidence region of north China

AIM: To investigate the possible association of G→A single nucleotide polymorphism (SNP) at the -1082 position of interleukin (IL)-10 promoter with susceptibility to esophageal squamous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA) in a population of a high incidence region of North China.

METHODS: IL-10-G1082A promoter SNP was genotyped by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) in 355 cancer patients (203 ESCC and 152 GCA) and 443 healthy controls.

RESULTS: Smoking significantly increased the risk of ESCC and GCA development (the age and sex adjusted OR = 1.42 and 2.64, 95%CI = 1.11-1.81 and 1.46-4.76, respectively). Similarly, family history of upper gastrointestinal cancer (UGIC) significantly increased the risk of developing ESCC and GCA (the age and sex adjusted OR = 1.44 and 3.10, 95%CI = 1.18-1.75 and 1.94-4.97, respectively). The A/A, A/G and G/G genotype frequencies of IL-10-G1082A were 60.3%, 37.0% and 2.7% in healthy controls, 57.6%, 39.9% and 2.5% in ESCC and 61.2%, 36.8% and 2.0% in GCA patients, respectively. The frequencies of A and G alleles were 78.8% and 21.2% in healthy controls, 77.6% and 22.4% in ESCC patients and 79.6%, 20.4% in GCA patients. The distribution of genotype and allelotype in ESCC and GCA patients was not significantly different from that in healthy controls (P>0.05). Compared to the A/A genotype, the combination of A/G and G/G genotypes did not show a significant effect on the risk of developing ESCC and GCA; the adjusted odds ratio was 0.92 (95% CI = 0.76-1.11) in ESCC and 0.95 (95% CI = 0.61-1.46) in GCA, respectively. When stratified for smoking status and family history of UGIC, the combination of A/G and G/G genotypes also did not show any significant influence on the risk of ESCC and GCA development compared to A/A genotypes.

CONCLUSION: IL-10-G1082A polymorphism might not be used as a stratification marker to predicate the risk of ESCC and GCA development in North China.

Impact of Gene Polymorphisms on Clinical Outcome for Stage IV Melanoma Patients Treated with Biochemotherapy: An Exploratory Study

Purpose: Biochemotherapy can achieve high response rates in advanced melanoma, but the factors that influence regression and survival remain unknown. The present exploratory study tested the hypothesis that cytokine gene polymorphisms predict clinical outcome in stage IV melanoma patients treated with biochemotherapy.

Experimental Design: Ninety patients with stage IV melanoma were treated with biochemotherapy, including cisplatin, vinblastine, and dacarbazine combined with interleukin (IL)-2 and IFN-α either with or without tamoxifen. Cytokine gene polymorphisms for IFN-γ (+874A→T) and IL-10 (−1082G→A) were assessed. X-ray repair cross-complementing gene 1 (XRCC1; Arg399Gln), xeroderma pigmentosum complementary group D (XPD; Lys751Gln), and excision repair cross-complementing gene 1 (ERCC1; codon 118) DNA repair polymorphisms were also determined.

Results: IFN-γ (+874A→T) gene polymorphism was statistically significantly associated with response (P = 0.001), progression-free survival (P = 0.0012), and overall survival (P &lt; 0.001), whereas the IL-10 polymorphism was marginally associated with response (P = 0.03) and overall survival (P = 0.065). Multivariate analysis revealed that IFN-γ (+874A→T) independently predicted overall survival (P = 0.003). The ERCC1 polymorphism was weakly associated with overall survival (P = 0.045). Combining polymorphisms for IFN-γ, IL-10, and ERCC1 stratified patients into four distinct groups with significantly different clinical outcome (P &lt; 0.001), so that patients with more “favorable” polymorphisms had a better outcome.

Conclusions: Cytokine gene polymorphisms predicted clinical outcome for advanced melanoma patients who received biochemotherapy. The combined effects of multiple genetic polymorphisms may provide more accurate prognostic information. Additional independent studies are needed to confirm these pilot findings.

Regulation of CTL responses to MHC-restricted class I peptide of the gp70 tumour antigen by splenic parenchymal CD4+ T cells in mice failing immunotherapy with DISC-mGM-CSF

Direct intratumour injection of the disabled infectious single-cycle-herpes simplex virus-encoding murine granulocyte/macrophage colony-stimulating factor (DISC-HSV-mGM-CSF) into established colon carcinoma CT26 tumours induced complete tumour rejection in up to 70% of treated animals (regressors), while the remaining mice developed progressive tumours (progressors). This murine Balb/c model was used to dissect the cellular mechanisms involved in tumour regression or progression following immunotherapy. CTLs were generated by coculturing lymphocytes and parenchymal cells from the same spleens of individual regressor or progressor animals in the presence of the relevant AH-1 peptide derived from the gp70 tumour-associated antigens expressed by CT26 tumours. Tumour regression was correlated with potent CTL responses, spleen weight and cytokine (IFN-gamma) production. Conversely, progressor splenocytes exhibited weak to no CTL activity and poor IFN-gamma production, concomitant with the presence of a suppressor cell population in the progressor splenic parenchymal cell fraction. Further fractionation of this parenchymal subpopulation demonstrated that cells inhibitory to the activation of AH-1-specific CTLs, restimulated in vitro with peptide, were present in the nonadherent parenchymal fraction. In vitro depletion of progressor parenchymal CD3+/CD4+ T cells restored the CTL response of the cocultured splenocytes (regressor lymphocytes and progressor parenchymal cells) and decreased the production of IL-10, suggesting that CD3+CD4+ T lymphocytes present in the parenchymal fraction regulated the CTL response to AH-1. We examined the cellular responses associated with tumour rejection and progression, identifying regulatory pathways associated with failure to respond to immunotherapy.

Association of polymorphism of IL-10 and TNF-A genes with gastric cancer in Korea

We performed this study to determine the role of polymorphisms of the IL-10 and TNF-alpha promoter genes in the carcinogenesis/pathogenesis of gastric cancer (GC) and peptic ulcer diseases (PUD) in Korea. A total of 232 patients with gastric diseases and 120 healthy controls were included. Polymorphisms of IL-10-1082/-592 gene and TNF-A-308 gene were genotyped by PCR-RFLP. There were no differences in genotypes and allele frequencies of IL-10 and TNF-A polymorphism between study group with GC or PUD and control group. In addition, there were no differences in genotypic frequencies according to H. pylori infection status, location of GC, and histologic type of GC. In conclusion, IL-10-1082/-592 and TNF-A-308 genetic polymorphisms may not be the important contributors to GC in Korea.

Ammonium trichloro(dioxoethylene-o,o')tellurate (AS101) sensitizes tumors to chemotherapy by inhibiting the tumor interleukin 10 autocrine loop

Cancer cells of different solid and hematopoietic tumors express growth factors in respective stages of tumor progression, which by autocrine and paracrine effects enable them to grow autonomously. Here we show that the murine B16 melanoma cell line and two human primary cultures of stomach adenocarcinoma and glioblastoma multiforme (GBM) constitutively secrete interleukin (IL)-10 in an autocrine/paracrine manner. This cytokine is essential for tumor cell proliferation because its neutralization decreases clonogenicity of malignant cells, whereas addition of recombinant IL-10 increases cell proliferation. The immunomodulator ammonium trichloro(dioxoethylene-o,o')tellurate (AS101) decreased cell proliferation by inhibiting IL-10. This activity was abrogated by exogenous addition of recombinant IL-10. IL-10 inhibition by AS101 results in dephosphorylation of Stat3, followed by reduced expression of Bcl-2. Moreover, these activities of AS101 are associated with sensitization of tumor cells to chemotherapeutic drugs, resulting in their increased apoptosis. More importantly, AS101 sensitizes the human aggressive GBM tumor to paclitaxel both in vitro and in vivo by virtue of IL-10 inhibition. AS101 sensitizes GBM cells to paclitaxel at concentrations that do not affect tumor cells. This sensitization can also be obtained by transfection of GBM cells with IL-10 antisense oligonucleotides. Sensitization of GBM tumors to paclitaxel (Taxol) in vivo was obtained by either AS101 or by implantation of antisense IL-10-transfected cells. The results indicate that the IL-10 autocrine/paracrine loop plays an important role in the resistance of certain tumors to chemotherapeutic drugs. Therefore, anti-IL-10 treatment modalities with compounds such as AS101, combined with chemotherapy, may be effective in the treatment of certain malignancies.

Mediation of enhanced transcription of the IL-10 gene in T cells, upon contact with human glioma cells, by Fas signaling through a protein kinase A-independent pathway

Elevated expression of IL-10 has been frequently observed in tumor tissues and tumor-infiltrating cells. We show herein that transcription of the IL-10 gene in primary peripheral T cells and T cell lines is up-regulated upon contact with glioma cells without an induction of apoptosis in those T cells. Glioma-associated IL-10 induction was suppressed by interrupting the engagement of Fas and its ligand (Fas-L) with the antagonistic Ab, ZB4, by reducing Fas-L expression of glioma cells using the Fas-L-specific ribozyme, or by preventing cell-to-cell contact in a Transwell culture setting. Cross-linking of Fas with the agonistic Ab, CH-11, triggered apoptosis and enhanced the expression of IL-10 in Jurkat cells at the transcriptional and translational levels. Inhibiting caspase activities by caspase inhibitors, Z-VAD (Z-Val-Ala-Asp(Ome)-fluoromethylketone) and Z-IETD (Z-Ile-Glu(Ome)-Thr(Ome)-Asp(Ome)-fluoromethylketone), abolished this IL-10 induction in Jurkat cells. Intracellular staining detected IL-10 proteins in Fas-cross-linked Jurkat cells and in PHA-activated T cells. However, few IL-10 proteins were detectable in Jurkat cells cocultured with glioma cells, indicating a requirement of other factors for IL-10 production. Direct activation of protein kinase A (PKA) by forskolin elevated the transcription of IL-10 in Jurkat cells. However, KT5720, a selective PKA inhibitor, reduced neither anti-Fas-triggered nor glioma-associated IL-10 expression. Phosphorylation of cAMP response element binding protein and activating transcription factor-1 in Jurkat cells was not affected by coculturing with glioma cells or by anti-Fas treatment, further suggesting a PKA-independent pathway. In summary, our results demonstrate nonlethal cross-talk between tumor and immune cells leading to IL-10 dysregulation in T cells, which might contribute to Fas-L(+) tumor-associated immunosuppression.

Cytokines and antitumor immunity

Currently, the notion of immunosurveillance against tumors is enjoying something of a renaissance. Even if we still refuse to accept that tumors arising in the normal host are unable to trigger an immune response because of the lack of initiation ("danger") signals, there is no doubt that the immune system can be manipulated experimentally and by implication therapeutically to exert anti-tumor effects. For this activity to be successful, the appropriate cytokine milieu has to be provided, making cytokine manipulation central to immunotherapy. On the other hand, the major hurdle currently preventing successful immunotherapy is the ability of tumors to evolve resistant variants under the pressure of immune selection. Here, too, the cytokine milieu plays an essential role. The purpose of this brief review is to consider the current status of the application of cytokines in facilitating antitumor immunity, as well their role in inhibiting responses to tumors. Clearly, encouraging the former but preventing the latter will be the key to the effective clinical application of cancer immunotherapy.

Feasibility to generate monocyte-derived dendritic cell from coculture with melanoma tumor cells in the presence of granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-4

OBJECTIVE

We investigated how melanoma cells and membrane-bound granulocyte/macrophage colony stimulating factor (mbGM-CSF) melanoma cell lines affect the differentiation of dendritic cells (DC) from CD14+ monocytes.

METHOD OF STUDY

The malignant melanoma cell lines (Conley and Jorp) and mbGM-CSF-positive cell lines (Conley B-F8 and Jorp C-E6) were cultured and cell-free supernatants were collected from each cell line cultures to assess the GM-CSF level. Adherent monocytes were cocultured for 6-7 days with irradiated mbGM-CSF and wild type melanoma cells (50 Gy) at each 1:1 and 0.1:1 ratio in six-well culture plates in ex vivo culture medium containing interleukin (IL)-4. Immunophenotyping was performed by triple color immunofluorescence staining with flow cytometry analysis.

RESULTS

GM-CSF was detected at low levels in the culture supernatants of Conley B-F8 (0.48 ng/10(6) cells/24 hr), whereas there was no detectable GM-CSF in that of Conley melanoma cell line. Monocytes cultured with GM-CSF/IL-4 generated the expression of high levels of HLA DR, CD1a and CD86, while the expression of CD14 and CD83 were in low amounts. However, the addition of GM-CSF to these cultures resulted in an increased expression of these markers and decreased that of CD14. Monocytes cocultured with Jorp C-E6 illustrated similar expression pattern of CD1a, HLA DR and CD14 in the presence or absence of GM-CSF as Conley B-F8 melanoma cell line. Monocytes cocultured with Conley B-F8 melanoma cells at 1:1 and 0.1:1 ratio showed no significant difference in expression of CD1a, CD14 and CD83 between the two ratios.

CONCLUSION

Our results illustrate the feasibility to generate monocyte-derived DC from coculture with melanoma tumor cells in the presence of GM-CSF and IL-4. However, mbGM-CSF tumor cells did not significantly enhance the DC differentiation through juxtacrine stimulation unless soluble GM-CSF was added in the culture media.

Interindividual variations in constitutive interleukin-10 messenger RNA and protein levels and their association with genetic polymorphisms

BACKGROUND

Genetic variations in the interleukin (IL)-10 gene promoter have been associated with levels of induced production of IL-10, disease susceptibility, and allograft rejection. Small amounts of this cytokine are constitutively produced and are important in maintaining the physiologic function of the cytokine network. In this study, we evaluated the distribution of IL-10 basal levels and its genetic regulation in a healthy Spanish population.

METHODS

Polymorphisms at the -1,082, -819, and -512 positions of the IL-10 promoter were analyzed by polymerase chain reaction amplification and hybridization with fluorescent-labeled allele-specific probes in 183 Spanish people. Levels of IL-10 messenger (m)RNA were tested by real-time reverse transcription-polymerase chain reaction in 123 healthy donors. Serum concentrations of IL-10 were measured by a highly sensitive ELISA, whereas protein amounts in lipopolysaccharide culture supernatants were quantified by an in-house ELISA.

RESULTS

The frequency of IL-10 promoter alleles and haplotypes in our population showed remarkable differences from other Caucasian populations. Large interindividual variations were found in mRNA and protein constitutive levels of IL-10, which allowed its classification in low and intermediate/high producers. We found statistical differences in mRNA concentration between the polymorphic variant GCC/GCC and the low producer genotypes. The G allele at position -1082 was the most important genetic factor in the regulation of constitutive IL-10 mRNA levels. Similarly, we also found an association of this polymorphic position with serum concentration greater than 2 pg/mL.

CONCLUSIONS

Constitutive levels of IL-10 (mRNA and serum protein) displayed remarkable interindividual variations, which are genetically controlled by polymorphic variants at the cytokine gene promoter.

Failure of blood-thymus barrier as a mechanism of tumor and trophoblast escape

A major process through which the immune system becomes tolerant to self-proteins involves the deletion of self-reactive clones in the thymus, but clonal deletion is not single mechanisms of thymic tolerance. There is now much evidence that intrathymic antigen expression results in anergy induction of T helper type-1 (Th1) clones in the periphery. Blood-thymus barrier is most important structure for prevention of unwanted penetration of antigens into the thymus. Impermeability of the barrier restrain induction of acquired thymic tolerance on unwanted antigens like microbes and tumor cells. Nevertheless, one of most important mechanism of tumor and trophoblast escape is in anergy of Th1 cells and in Th2 cells domination. Many mechanisms are included in disarrangement of Th1/Th2 balance in pregnancy and tumor bearers, but one of possibility is in failure of blood-thymus barrier. Possible consequences of blood-thymus barrier failure are trophoblast-specific or tumor-specific antigens penetrate into the thymus, deletion or anergy of antigen-specific clones and acquired thymic tolerance induction. Blood-thymus barrier is variable structure in anatomical and functional sense so that in certain condition foreign antigens probably can permeate across the barrier. Probability that some factors like hormones, cytokines, prostaglandine and neuromediators can affect blood-thymus barrier permeability and contribute in mechanisms of trophoblast and tumor escape is real but relatively unexplored.

Origin of anti-tumor immunity failure in mammals and new possibility for immunotherapy

There is now much evidence that tumors can be immunogenic. Tumor cells very often express antigens in a form recognizable by the host immune system, but most frequently without consequences on tumor progression. This has been shown in many experimental models and different experimental conditions. Immediate mechanisms for the escape of tumors from immune response are very similar with mechanisms for the escape of fetoplacental unit (as an allograft) from maternal immune response. Similarity between these two mechanisms is so significant that any randomness is banished. Mechanisms of anti-tumor immunity in mammals are substantially different in comparison with mechanisms of anti-tumor immunity in other classes of vertebrates. Moreover, type of most frequently tumors in non-mammalians vertebrates is also significant different. Incidence of malignant tumors in non-mammalians vertebrates is significantly less than incidence of malignant tumors in mammals. These facts indicate that immune system of mammals during anti-tumor immune response is tricked with similarity between tumor cells and trophoblast or other placental cells. It may be a specific evolutionary approach in rendering of anti-tumor immunity failure in mammals, and new possibility for anti-tumor immunotherapy.

Peripheral mononuclear cell IL-10 and IL-12 production is not impaired in patients with advanced cancer and severe infection

We assessed whether interleukin (IL)-10 and IL-12 production of blood mononuclear cells (PBMC) after lipopolysaccharide (LPS 0.1 microgram/ml, 1.0 microgram/ml) or phytohemagglutinin (PHA 5 microgram/ml) stimulation in advanced cancer patients with severe infections (IA, n=10) differs from those without infection (AC,n =10) or healthy controls HC (n=10). PBMCs in IA produced statistically higher median IL-12 levels than those in HC; LPS 0.1 (P=0.05), LPS 1.0 (P=0.019) and PHA (P=0.024). IL-10 production was always higher in AC than in HC. Both the IL-10 (LPS 1.0; P=0.018) and IL-12 (LPS 0.1;P =0.046) production of PBMCs were significantly higher in IA than one month afterwards. In conclusion, the PBMC production of IL-10 and IL-12 in advanced cancer patients with or without infection was not impaired but rather enhanced compared to that of HC. One month after infection, however, PBMC production clearly decreased, suggesting a kind of hyporeactivity.

Expression of interleukin-18, interferon-gamma and interleukin-10 in hepatocellular carcinoma

This is the first report on the detection of IL-18, IFN-gamma and IL-10 proteins in hepatocelllular carcinoma. In the apparently normal surrounding tissue, 13 out of 17 paired specimens showed positive immunoreactivity to IL-18 (76.5%) compared with six out of 17 in the tumour portion (35.3% of specimens). Thus, a significantly higher number of IL-18 positive specimens was found in the hepatocytes of apparently normal surrounding tissue compared with the tumour (P=0.018). In contrast, the number of specimens with positive immunoreactivity to the antibody against the Th1 cytokine, IFN-gamma expression in the hepatocytes was lower. Only one specimen from the apparently normal surrounding tissue (one out of 17; 5.9%) and three other specimens from the tumour portion (three out of 17; 17.6%) had positive immunoreactivity. Similarly, the expression of the Th2 cytokine, IL-10 in normal (four out of 17; 23.5%) and tumour portions (five out of 17; 29.4%) was also low. Thus, there did not appear to be predominant Th2 immune response as denoted by IL-10 expression. Using the Spearman correlation rank test, a significant correlation between IL-18 expression in the apparently normal surrounding tissue and high alpha-foetoprotein (AFP) levels of >350 IU/l. No correlation between IL-18 expression in the tumour portion and clinicopathological factors was found. There was also no correlation found between IL-18 and the other cytokines, namely, IFN-gamma and IL-10 expression These new findings provide additional information on the type of cytokines expressed in the tumour microenvironment and give a further insight into the role of cytokines in the pathogenesis of cancer which is critical for the development of effective immunotherapeutic approaches for cancer therapy in the future.

Prognostic significance of circulating IL-10 and IL-6 serum levels in colon cancer patients undergoing surgery

The prognostic significance of IL-10 and IL-6 serum levels in colon cancer patients undergoing surgery was investigated. To this end, 50 candidate patients with colon cancer for surgery were admitted to the study. Of these, 30 could be subjected to a potentially curative surgery. Cytokine serum levels at several time points before and after surgery were measured by ELISA. Circulating levels of IL-10 and IL-6 were found to be elevated in cancer patients with respect to controls. Both IL-10 and IL-6 serum levels were demonstrated to predict the likelihood of curative surgery (predictive accuracy, 83.3%). IL-10 serum levels returned to normal in all but 6 patients who underwent curative surgery. These latter had tumor recurrence (predictive accuracy, 100%). In contrast, IL-6 serum levels significantly decreased in all patients, regardless of whether cure was surgically achieved, but did not normalize. On multivariate analysis, basal IL-10 serum levels were found to be among the variables significantly predicting the disease-free survival rate. Stepwise regression selected tumor stage, basal IL-10 serum level, and basal CEA serum level as the best combination of variables for prediction of the likelihood of tumor recurrence. In conclusion, preoperative serum levels of IL-10 were shown to be useful markers for predicting both likelihood to perform curative surgery and, in combination with the 16th postoperative day IL-10 serum levels, tumor recurrence (predictive accuracy, 73.6 and 96%, respectively). IL-6 serum levels were found to have a more limited prognostic role.

Vaccines in oncology: background and clinical potential

Cancer is one of the leading causes of death in Western society. Despite improvements in screening, diagnosis and treatment of cancer, many patients ultimately succumb to their disease. Advances in molecular biology and our increased understanding of how the immune system functions have led to an intense interest in the development of cancer vaccines.

Interleukin-10 and interferon-gamma levels within the peritoneal cavity of patients with gastric cancer

BACKGROUND AND OBJECTIVES

Immune status in the peritoneal cavity of patients with gastric cancer remains largely unknown. To clarify the clinical significance of the host immune response within the peritoneal cavity, we examined the levels of interferon-gamma (IFN-gamma), a type 1 cytokine, and interleukin-10 (IL-10), a type 2 cytokine, in peritoneal washings obtained from patients with gastric cancer.

METHODS

Both the concentrations of IFN-gamma and of IL-10 in peritoneal washings obtained during surgery from 56 patients with gastric cancer were determined by an enzyme-linked immunosorbent assay.

RESULTS

The IFN-gamma level was not correlated with the IL-10 level. The IL-10 level increased in a stage-dependent manner. The high IL-10 level correlated with an unfavorable outcome, whereas there was no relationship between the IFN-gamma level and survival rate. However, among the stage III-IV cancer patients, the high IFN-gamma level correlated with a favorable outcome, while there was no relationship between the IL-10 level and survival rate.

CONCLUSION

Although the IL-10 level increases with tumor progression, the outcome of patients with advanced gastric cancer may be affected by the IFN-gamma level, but not by the IL-10 level, in the peritoneal cavity.

Interleukin-10 and the interleukin-10 receptor

Interleukin-10 (IL-10), first recognized for its ability to inhibit activation and effector function of T cells, monocytes, and macrophages, is a multifunctional cytokine with diverse effects on most hemopoietic cell types. The principal routine function of IL-10 appears to be to limit and ultimately terminate inflammatory responses. In addition to these activities, IL-10 regulates growth and/or differentiation of B cells, NK cells, cytotoxic and helper T cells, mast cells, granulocytes, dendritic cells, keratinocytes, and endothelial cells. IL-10 plays a key role in differentiation and function of a newly appreciated type of T cell, the T regulatory cell, which may figure prominently in control of immune responses and tolerance in vivo. Uniquely among hemopoietic cytokines, IL-10 has closely related homologs in several virus genomes, which testify to its crucial role in regulating immune and inflammatory responses. This review highlights findings that have advanced our understanding of IL-10 and its receptor, as well as its in vivo function in health and disease.

Cytokines and malaria parasitemia

The balance between pro- and antiinflammatory cytokines may be important in malaria presentation and outcome. Malaria tends to be more severe in children than in adults, presumably because partial immunity develops with age. However, the full nature of, and age-related differences in, anti-malarial immunity are unknown. We compared: (1) serum and cell-specific cytokines of patients with acute malaria to those of patients with other acute illnesses and to those of healthy adults and (2) the cytokine responses of parasitemic children and parasitemic adults. Flow cytometry was done on the peripheral blood mononuclear cells of 148 hospitalized children, 161 febrile hospitalized adults, and 20 healthy adults in Malawi, Africa, a malaria-endemic country. Serum cytokines were also assessed for 80 of these patients. Thirty-eight participants were parasitemic with Plasmodium falciparum. Serum interleukin (IL)-10 (an antiinflammatory, immunoregulatory, and type 2 cytokine) levels were higher in malaria patients than in other patients (medians 502 pg/mL vs 16 pg/mL, P = 0.002), and the percentages of various lymphocyte populations making IL-6 (a proinflammatory, type 2 cytokine regulating iron distribution) were lower in malaria patients than in other patients (e.g., for spontaneous production by children's CD8(+) T cells: medians 1.4% vs 33.1%, P = 0.004). For adult patients, the percentages of lymphocytes spontaneously making IL-4 (a type 2 cytokine) were significantly lower in those with malaria than in those without malaria (medians 0.9% vs 2.1%, P = 0.005). The percentages of monocytes spontaneously making IL-8 (a chemotactic, proinflammatory chemokine) were higher in parasitemic children than in parasitemic adults (medians 5.8% vs 1.7%, P = 0.003). A number of cellular proinflammatory, type 1 parameters were significantly higher in all children (with or without malaria) than in all adults; these included the percentages of various lymphocyte populations making IL-6, both IL-6 and interferon-gamma, or IL-8. These data support the importance of IL-10 in malaria parasitemia. Given the lack of an IL-4 (type 2) response, IL-10's primary role may be immunoregulatory rather than type 2 in nature. In this study, the immune response to malaria was more proinflammatory in children than in adults. This difference, if corroborated by other studies, could be related to malaria's greater severity in children.