Role of dendritic cells in progression and clinical outcome of colon cancer

High expression of CD11c indicates favorable prognosis in patients with gastric cancer

AIM: To determine the relationship between CD11c expression level and prognosis in patients with gastric cancer (GC).

METHODS: This retrospective survival study was performed from July 31, 2008 to June 30, 2014. Our study inclusion criteria included all the patients with GC who underwent surgical resection between January 1998 and December 2009 in the Third Affiliated Hospital of Soochow University. CD11c expression levels in 140 patients with GC at different UICC stages were evaluated using immunohistochemistry, and GC tissues from 16 cases were further verified by qRT-PCR. The χ² test was used to compare the patient- and disease-related factors between the low CD11c expression group and the high expression group. Univariate probabilities of overall survival (OS) and disease-free survival (DFS) were assessed using the Kaplan-Meier method. The log rank test was used to compare survival curves. Different multivariate COX models were used to estimate the association between CD11c expression and both death and recurrence risk in GC patients.

RESULTS: The average CD11c expression level was 5.1 ± 1.8/high power field (HPF) in 10 gastritis samples, 4.5 ± 2.3/HPF in 10 gastric polyp samples and 9.7 ± 6.3/HPF in 140 gastric cancer samples, respectively. The CD11c expression level was significantly decreased from UICC stage I to stage IV (stage I: 16.0 ± 7.4, stage II: 10.4 ± 5.5, stage III: 9.4 ± 6.1, stage IV: 5.3 ± 3.2, P < 0.001). Patients in the high CD11c expression group had a greater 3- and 5-year OS probability and longer median survival time compared with the low CD11c expression group, (67.7% vs 39.2%; 51.4% vs 29.0%; 67.0 mo vs 28.0 mo; χ² = 6.80, P = 0.009), and had a greater 3- and 5-year DFS probability and longer median DFS time (63.7% vs 24.0%; 49.1% vs 11.9%; 64.0 mo vs 18.0 mo; χ² = 15.39, P < 0.001). Patients with high CD11c high expression had a reduced risk of death (HR = 0.56, 95%CI: 0.33-0.98, P < 0.05) and relapse (HR = 0.39, 95%CI: 0.23-0.67, P < 0.01) compared with patients with low CD11c expression after adjustment of potential confounders, with the exception of tumor size. However, the protective effect related to death (HR = 0.90, 95%CI: 0.49-1.67, P = 0.749) and relapse (HR = 0.65, 95%CI: 0.36-1.19, P = 0.160) disappeared when tumor size was incorporated into the model.

CONCLUSION: High expression of CD11c decreased the risk of death and relapse, and may be regarded as an alternative indicator of favorable prognosis in patients with GC.

Relationship between dendritic cells, interleukin-23 and ulcerative colitis

AIM: To evaluate the expression of dendritic cell (DCs) and interleukin (IL)-23 in ulcerative colitis (UC) to improve the diagnosis and treatment of UC.

METHODS: Sixty UC and 60 irritable bowel syndrome (IBS) colon tissue sections were used to detect the expression of S100⁺ DCs, CD83⁺ DCs and IL-23P19 by immunohistochemistry. The expression of IL-23P19 in the mucosa was compared between acute and chronic stages, between mild and severe type diseases, and between before and after mesalazine treatment in the UC group.

RESULTS: There was a statistical difference in the infiltrated densities of S100⁺ DCs, CD83⁺ DCs and IL-23P19 cells between the UC group and IBS group (27.48 cells/mm² ± 9.23 cells/mm²vs 9.20 cells/mm² ± 3.91 cells/mm², 6.62 cells/mm² ± 2.59 cells/mm²vs 3.20 cells/mm² ± 1.59 cells/mm², 105.97 cells/mm² ± 25.30 cells/mm²vs 32.48 cells/mm² ± 11.61 cells/mm², P < 0.05). In the UC group, there was a statistical difference in the expression of IL-23P19 between acute and chronic stages, between mild and severe type diseases, and between before and after mesalazine treatment (113.83 cells/mm² ± 28.83 cells/mm²vs 49.35 cells/mm² ± 8.11 cells/mm², 75.03 cells/mm² ± 21.39 cells/mm²vs 117.38 cells/mm² ± 28.32 cells/mm², 109.89 cells/mm² ± 25.73 cells/mm²vs 47.25 cells/mm² ± 8.67 cells/mm², P < 0.05).

CONCLUSION: In UC colon tissue, the production of IL-23P19 increases with the increase in the infiltrated density and activity of DCs. The expression of IL-23P19 may be used as an indicator for evaluation of the disease stage, the degree of pathological changes and treatment efficacy in UC.

Difference in distribution profiles between CD163+ tumor-associated macrophages and S100+ dendritic cells in thymic epithelial tumors

Background

In a number of human malignancies, tumor-associated macrophages (TAMs) are closely involved in tumor progression. On the other hand, dendritic cells (DCs) that infiltrate tumor tissues are involved in tumor suppression. However, there have been very few reports on the distribution profiles of TAMs and DCs in thymic epithelial tumors. We examined the difference in the distribution profiles between TAMs and DCs in thymoma and thymic carcinoma.

Methods

We examined 69 samples of surgically resected thymic epithelial tumors, namely, 16 thymic carcinomas and 53 thymomas, in which we immunohistochemically evaluated the presence of TAMs using CD68 and CD163 as markers and DCs using S100 as the marker in tumor tissue samples in comparison with normal thymic tissues.

Results

The percentage of samples with a large number of CD68+ TAMs was not significantly different between thymic carcinoma and thymoma (7/16 versus 16/53, p = 0.904). However, the percentage of sample with a large number of CD163+ TAMs was significantly higher in thymic carcinoma than in thymoma (15/16 versus 34/53, p = 0.024). In contrast, the percentage of samples with a large number of S100+ DCs was significantly lower in thymic carcinoma than in thymoma (2/16 versus 23/53, p = 0.021).

Conclusions

To the best of our knowledge, we are the first to show a high percentage of CD163+ TAMs and a low percentage of S100+ DCs in thymic carcinoma samples, and our findings may provide an idea for future targeted therapeutic strategies for thymic carcinoma using antibodies that inhibit monocyte differentiation to TAMs, thereby skewing TAMs differentiation toward DCs.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_215

The clinical significance of DC-SIGN and DC-SIGNR, which are novel markers expressed in human colon cancer

Background

Colon cancer has always been diagnosed at a late stage, which is associated with poor prognosis. The currently used serum tumor markers CEA and CA19-9 display low sensitivity and specificity and may not have diagnostic value in early stage colon cancer. Thus, there is an urgent need to identify novel serum biomarkers for use in the early detection of colon cancer.

Methods

In this study, the expression of DC-SIGN and DC-SIGNR in serum was detected by enzyme-linked immunosorbent assay (ELISA). DC-SIGN and DC-SIGNR expression was detected in cancer tissues by immunohistochemistry (IHC).

Results

The level of sDC-SIGN was lower in patients than in the healthy controls, while the level of sDC-SIGNR in patients was higher than in the healthy controls. Both sDC-SIGN and sDC-SIGNR had diagnostic significances for cancer patients, and the combined diagnosis of these two markers was higher than both of them alone. Furthermore, there were significant differences between both sDC-SIGN and sDC-SIGNR in stage I/II patients and the healthy controls. Moreover, high sDC-SIGN level was accompanied with the long survival time. Additionally, DC-SIGNR was negative in the cancer foci and matched normal colon tissues but was weakly positive between the cancer foci. DC-SIGN staining was faint in matched normal colon tissues, strong in the tumor stroma and the invasive margin of colon cancer tissues, and negatively correlated with the sDC-SIGN level in serum from the same patient. Interestingly, the percent survival of patients with a DC-SIGN mean density of>0.001219 (the upper 95% confidence interval of matched normal colon tissues) was higher than for all other patients.

Conclusion

DC-SIGN and DC-SIGNR are blood-based molecular markers that can potentially be used for the diagnosis of early stage patients. Moreover, expression of DC-SIGN in serum and cancer tissues may affect the survival time for colon cancer patients.

Accumulation of CD208⁺ mature dendritic cells does not correlate with survival time in oral squamous cell carcinoma patients

PURPOSE

To investigate the distribution and clinical outcomes of tumor-infiltrating CD208(+) mature dendritic cells (mDCs) in patients with oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Using immunohistochemical analysis, the distribution of CD208(+) mDCs in adjacent non-neoplastic tissues (NTs) and tumor tissue, including the tumor stroma (TS) and tumor nest (TN), of 79 patients with OSCC was evaluated. The analysis was quantitative, and the number of positive cells was counted in 5 microscopic high-power fields (×400). At the gene expression level, CD208 expression also was assessed by quantitative polymerase chain reaction. Kaplan Meier analyses were used to analyze the prognostic value of tumor-infiltrating CD208(+) mDCs.

RESULTS

The number of tumor-infiltrating CD208(+) mDCs was larger in the TS and TN than in the NTs (P < .0001) and the number of CD208(+) mDCs in the TS was larger in patients with OSCC and lymph node positivity (P < .05). At the gene expression level, CD208 also was upregulated in patients with lymph node positivity (P < .05). The number of infiltrating CD208(+) mDCs was not associated with a patient's survival time.

CONCLUSIONS

The number of tumor-infiltrating CD208(+) mDCs in the TS was larger in patients with OSCC and lymph node positivity, but the accumulation of CD208(+) mDCs did not correlate with survival time in patients with OSCC.

Tumour microenvironment of both early- and late-stage colorectal cancer is equally immunosuppressive

BACKGROUND

Tumour microenvironment (TME) of advanced colorectal cancer (CRC) suppresses dendritic cell (DC) maturation. Here, our aim was to determine how the microenvironment of early-stage tumours influences DCs.

METHODS

Tumour-conditioned media (TCM) was generated by culturing explant tumour tissue in vitro (n=50). Monocyte-derived DCs (MDDCs) of healthy donors or cancer patients were pretreated with TCM and stimulated with lipopolysaccharide (LPS). DC maturation was assessed by flow cytometry and cytokine production measured by ELISA.

RESULTS

TCM from both early- and late-staged tumours abrogated LPS-induction of IL-12p70 secretion, while increasing IL-10. The profile of inflammatory mediators in TCM was similar across stages, and all increased pSTAT3 expression by DCs.CRC patient DCs (n=31) secreted low levels of IL-12p70 and failed to upregulate expression of maturation markers in response to LPS. Furthermore, in vitro culture of autologous DCs with TCM did not change the hypo-responsiveness of patient DCs.

CONCLUSION

Our data demonstrates that the TME of all stages of CRC contains inflammatory mediators capable of suppressing local DCs. MDDCs obtained from CRC patients are hyporesponsive to stimuli such as LPS. Measures to reverse the negative influence of the TME on DCs will optimise cancer vaccines in both early- and late-stage CRC.

Defective generation and maturation of dendritic cells from monocytes in colorectal cancer patients during the course of disease

Colorectal cancer (CRC) is the second-leading cause of cancer-related deaths in Western countries. Today, the role of the host’s immune system in controlling the progression and spread of solid tumors is broadly established. Tumor immunosurveillance escape mechanisms, such as those involving dendritic cells (DCs), the most important antigen-presenting cells, are likewise recognized processes involved in cancer. The present study evaluates the ability of CRC patients to generate DCs in vitro from circulating monocytes at both pre- and post-operative timepoints; the results are correlated with the stage of disease to shed light on the systemic immune statuses of CRC patients. Our data showed that patients’ DCs had lower co-stimulatory molecule expression and were less able to present antigens to allogeneic T cells compared to healthy controls’ (HC) DCs. Furthermore altered cytokine secretion, such as increased IL-10 and reduced IL-12 and TNF-α, was observed. At the post-operative timepoints we observed a recovery of the patients’ ability to generate immature DCs, compared to HCs, but the maturational capacity remained affected. Our study conclusively highlights the persistently impaired in vitro generation of fully mature and functional DCs, which appears to be more altered during advanced stages. This work sheds light on a dendritic cell-based tumor immune escape mechanism that could be useful for the development of more effective immunotherapeutic strategies.

Role of tumor-infiltrating CD11b+ antigen-presenting cells in the progression of gastric cancer

BACKGROUND

Tumor-infiltrating antigen-presenting cells (APCs), involving tumor-associated macrophages and tumor-infiltrating dendritic cells, play an important role in tumor immunity and immune escape. The aim of this study was to determine whether tumor infiltrating CD11b(+) APCs may affect tumor progression and clinical outcome.

METHODS

The immunohistochemical analysis was used to evaluate the expression of CD11b, FOXP3, and CD8 in 214 gastric cancer tissues. Concentrations of immunosuppressive cytokines in medium conditioned by gastric cancer cells were measured by enzyme-linked immunosorbent assay. Effects of addition of tumor-conditioned media on CD11c(+) cells were examined by flow cytometry.

RESULTS

Almost all tumor-infiltrating CD11b(+) cell expressed CD11c and was considered to be APCs. High CD11b(+) cell infiltration was significantly correlated with huge tumor, positive venous invasion, lymph node metastasis, and tumor, node, metastasis stage. Patients with high CD11b(+) cell infiltration had a poorer surgical outcome than those with low CD11b infiltration. Multivariate analysis revealed that CD11b(+) cell infiltration was one of the independent prognostic factors. Tumor-conditioned medium obtained from several gastric cancer cell lines contained immunosuppressive cytokines, transforming growth factor-beta, interleukin-10, and vascular endothelial growth factor. The addition of tumor-conditioned medium decreased the expression of major histocompatibility complex-II and increased the expression of CD11b and programmed death ligand 2 on CD11c(+) APCs. Infiltration of CD11b(+) cells significantly correlate with the degree of FOXP3(+) cell infiltration but not with CD8(+) cell infiltration.

CONCLUSIONS

Tumor-infiltrating CD11b(+) APCs affected local tumor cell-immune cell interactions and correlated to the poor prognosis of the patients with gastric cancer.

Quantification of blood dendritic cells in colorectal cancer patients during the course of disease

Colorectal cancer is a malignancy with poor prognosis that might be associated with defective immune function. The aim of the present study was to investigate circulating dendritic cells in colorectal cancer patients, in order to contribute to elucidate tumor-escape mechanisms and to point out a possible correlation with the clinical condition of the disease. Therefore, we enumerated ex vivo myeloid and plasmacytoid dendritic cells, through multicolor flow cytometry, in 26 colorectal patients and 33 healthy controls. Furthermore we performed several analyses at determined time points in order to define the immunological trend of cancer patients after surgery and other conventional treatments. At the pre-operative time point the absolute number of plasmacytoid dendritic cells in cancer patients was significantly reduced in comparison to controls, this result being mainly referred to stage III-IV patients. The number of myeloid dendritic cells did not show any significant difference compared to healthy controls; interestingly the expression of the tolerogenic antigen CD85k was significantly higher on cancer patients' myeloid dendritic cells than controls'. At the following samplings, circulating dendritic cell absolute number did not show any difference compared to controls. Conclusively the impairment of the number of circulating dendritic cells may represent one of the tumor escape mechanisms occurring in colorectal cancer. These alterations seem to be correlated to cancer progression. Our work sheds light on one of dendritic cell-based tumor immune escape mechanisms. This knowledge may be useful to the development of more effective immunotherapeutic strategies.

The density of macrophages in colorectal cancer is inversely correlated to TGF-β1 expression and patients' survival

The role of macrophages in colorectal cancer tumorogenesis is complex because they can both prevent and promote tumor development. We investigated CD68-positive cell infiltration in tumor tissue and its correlations with proteins of TGF-β1 signaling pathway and survival of the patients after surgical therapy. A non-selected panel of 210 primary tumors of colorectal origin was investigated immunohistochemically with antibodies against CD68, TGF-β1, TGFβRII and Smad4. Lower CD68 infiltration in tumor stroma was associated with expression of TGF-β1 (p = 0.002) and SMAD4 (p = 0.090) in tumor cell cytoplasm and with TGFβRII expression (p = 0.017) in tumor cells membranes. The absence of SMAD4 immune deposits in tumor cell nuclei was more often seen in biopsies with low number of CD68 in the invasive front (p = 0.044). The low number of CD68-positive cells was significantly associated with several adverse clinical and histological tumor characteristics as the presence of metastases in local lymph nodes (p = 0.047), distant metastases (p = 0.0003), advanced tumor stage (p = 0.006), tumor cell invasion of blood, lymph vessels or perineural invasion (p = 0.004), higher histological types (p = 0.0002) and lower grade of inflammatory infiltration in the invasive front (p = 0.002). Moreover, the low grade of CD68 appeared to be significant unfavorable factors of prognosis of the patients with colorectal cancer. The results of our study confirm the prognostic significance of low level of tumor-associated macrophage infiltration in colorectal cancer as unfavorable marker for survival of the patients.

Numerical defect of circulating dendritic cell subsets and defective dendritic cell generation from monocytes of patients with advanced melanoma

The behaviour of circulating dendritic cells (DCs) and DC generation from monocytes in melanoma patients during the progression of disease have not been described. We report a significant decrease in the absolute number of total DCs, which mainly affects plasmacytoid DCs in stage IV. Additionally, monocyte-DC generation is less efficient in advanced stages, resulting in DCs that exhibit increased phagocytic capacity, potentially indicating a less mature state. These findings elucidate aspects of basic tumour-mediated immunosuppression, which may have implications for immunotherapeutic approaches, suggesting that the selection of patients for immunotherapy should also be made on the basis of their immune status.

Tumor-infiltrating B cells come into vogue

Lymphocyte infiltration into solid tumors has been recognized as a main determinator of positive prognosis. For the most part this is attributed to cytotoxic T cells capable of directly destroying malignant cells. However, when considering the complex composition of the human immune system, recent findings of Nielsen et al on a potentially central role of tumor-infiltrating B cells is not really surprising. In this commentary article, I want to highlight the enormous potential impact of this observation for basic and translational research, prognostic procedures and ultimately for the development of future therapeutic concepts.

Prognostic impact of Metadherin-SND1 interaction in colon cancer

The interaction between Metadherin (MTDH) and Staphylococcal nuclease homology domain containing 1 (SND1) is involved in tumorigenesis and tumor progression of several human malignancies. However, its roles in colon cancer are still unclear. To investigate the clinical value of MTDH and SND1 expression in colon cancer. Immunohistochemical staining was performed to detect the expression of MTDH and SND1 using human colon cancer and their corresponding non-cancerous colon tissues from 196 patients' biopsies. Positive expression of MTDH and SND1 were both increased in colon cancer tissues compared to paired non-cancerous colon tissues. There was a positive correlation between MTDH and SND1 expression in colon cancer tissues (r = 0.86, p < 0.001). In addition, their positive expression were both significantly associated with nodal status (both p = 0.02), pathological stage (p = 0.006 and 0.008, respectively) and differentiation (both p = 0.03). Moreover, the overall survival in colon cancer patients with positive expression of MTDH and SND1 were significantly shorter than those without their expression (both p = 0.01). Furthermore, multivariate Cox regression analysis suggested that positive expression of MTDH and SND1 was an independent poor prognostic predictor in colon cancer. Our data suggest that the increased expression of MTDH and/or SND1 is closely related to carcinogenesis, progression, and prognosis of colon cancer. The co-expression of MTDH/SND1 may be a novel distinctive marker to benefit us in prediction of the prognosis in colon cancer.

TGF-β-induced epithelial-mesenchymal transition: a link between cancer and inflammation

Metastatic spread of tumor cells to vital organs is the major cause of death in cancer. Accumulating data support an important role of infiltrating immune cells in promoting carcinoma progression into metastatic disease. Tumor-infiltrating immune cells produce and secrete cytokines, growth factors and proteases that re-activate latent developmental processes including epithelial-mesenchymal transition (EMT). EMT provides tumor cells with invasive, migratory and stem cell properties allowing them to disseminate and propagate at distant sites. Induction of EMT requires two criteria to be fulfilled: (i) cells are competent to undergo EMT (ii) an EMT-permissive microenvironment exists. The cytokine TGF-β, which is expressed by tumor-infiltrating immune cells, stands out as a master regulator of the pro-invasive tumor microenvironment. TGF-β cooperates with stem cell pathways, such as Wnt and Ras signaling, to induce EMT. In addition, TGF-β contributes to an EMT-permissive microenvironment by switching the phenotypes of tumor-infiltrating immune cells, which thereby mount pro-invasive and pro-metastatic immune responses. In this review, we discuss the role of TGF-β-induced EMT as a link between cancer and inflammation in the context of questions, which from our point of view are key to answer in order to understand the functionality of EMT in tumors.