Breast cancer diagnostics based on extracellular DNA and RNA circulating in blood

Extracellular DNA and RNA were extracted from blood plasma and cell surface-bound fractions of healthy women and patients with fibroadenoma and breast cancer. Frequency of methylation of RASSF1A, Cyclin D2, and RARβ2 genes was detected in the extracellular DNA using methylation-specific PCR. Methylation of at least one of these genes was found in plasma of 13% patients with nonmalignant breast fibroadenoma and in 60% of breast cancer patients. Employment cell-surface bound DNA as the substrate for PCR increased the detection frequency of gene methylation up to 87% in patients with fibroadenoma and 95% in breast cancer patients. In clinically healthy women the methylation markers have not been found in extracellular DNA. GAPDH, RASSF8, Ki-67 mRNAs, and 18S rRNA copies were quantified using RT-qPCR of extracellular RNA circulating in blood of patients with breast tumors and healthy controls. The major part of blood extracellular RNA is associated with cell surface. ROC analysis has shown that differences in concentrations 18S RNA, RASSF8, and Ki-67 mRNAs in blood plasma are highly sensitive and specific in discrimination of benign and malignant breast tumors. Thus, analysis of methylated forms of tumor suppressor genes in blood extracellular and quantification of specific extracellular RNA circulating in blood plasma may detect mammary gland tumors and discriminate malignant and benign neoplasms.     

miRNA expression profiling for identification of potential breast cancer biomarkers

To identify micro RNA (miRNA) biomarker candidates for early detection of breast cancer and detection of minimal residual breast cancer, we performed miRNA expression profiling in pooled RNA samples from breast tumors, and from bone marrow mononuclear cells, peripheral blood mononuclear cells and plasma from healthy controls. We found substantially higher levels of five miRNAs in the breast tumors compared to the normal samples. However, validation of these miRNA levels, and seven other candidates selected from the literature, in individual samples from healthy controls and patients with non-metastatic breast cancer did not suggest further examination of their biomarker potential.     

miRNA expression profiling for identification of potential breast cancer biomarkers

To identify micro RNA (miRNA) biomarker candidates for early detection of breast cancer and detection of minimal residual breast cancer, we performed miRNA expression profiling in pooled RNA samples from breast tumors, and from bone marrow mononuclear cells, peripheral blood mononuclear cells and plasma from healthy controls. We found substantially higher levels of five miRNAs in the breast tumors compared to the normal samples. However, validation of these miRNA levels, and seven other candidates selected from the literature, in individual samples from healthy controls and patients with non-metastatic breast cancer did not suggest further examination of their biomarker potential.     

Extracellular circulating nucleic acids in human plasma in health and disease

The concentration of extracellular DNA and RNA in blood plasma of healthy donors, trauma patients, patients with breast and lung cancer, nonmalignant breast tumors and nonmalignant lung diseases were estimated. Significant amounts of extracellular RNA were found in plasma of trauma patients. The concentration of DNA and RNA in plasma of trauma patients correlates with the extent of posttraumatic organ failure. Extracellular RNA was not found in the plasma of breast cancer patients and patients with nonmalignant breast tumors, whereas a very high concentration of extracellular RNA was found in patients with malignant and nonmalignant diseases of lung.     

Extracellular Circulating Nucleic Acids in Human Plasma in Health and Disease

The concentration of extracellular DNA and RNA in blood plasma of healthy donors, trauma patients, patients with breast and lung cancer, nonmalignant breast tumors and nonmalignant lung diseases were estimated. Significant amounts of extracellular RNA were found in plasma of trauma patients. The concentration of DNA and RNA in plasma of trauma patients correlates with the extent of posttraumatic organ failure. Extracellular RNA was not found in the plasma of breast cancer patients and patients with nonmalignant breast tumors, whereas a very high concentration of extracellular RNA was found in patients with malignant and nonmalignant diseases of lung.     

Interleukin 2 and interleukin 10 function synergistically to promote CD8+ T cell cytotoxicity,which is suppressed by regulatory T cells in breast cancer

The precise role of interleukin (IL)-10 in breast cancer is not clear. Previous studies suggested a tumor-promoting role of IL-10 in breast cancer, whereas recent discoveries that IL-10 activated and expanded tumor-resident CD8⁺ T cells challenged the traditional view. Here, we investigated the role of IL-10 in HLA-A2-positive breast cancer patients with Grade III, Stage IIA or IIB in-situ and invasive ductal carcinoma, and compared it with that of IL-2, the canonical CD8⁺ T cell growth factor. We first observed that breast cancer patients presented higher serum levels of IL-2 and IL-10 than healthy controls. Upon prolonged TCR stimulation, peripheral blood CD8⁺ T cells from breast cancer patients tended to undergo apoptosis, which could be prevented by the addition of IL-2 and/or IL-10. The cytotoxicity of TCR-activated CD8⁺ T cells was also enhanced by exogenous IL-2 and/or IL-10. Interestingly, IL-2 and IL-10 demonstrated synergistic effects, since the enhancement in CD8⁺ T cell function when both cytokines were added was greater than the sum of the improvements mediated by each individual cytokine. IL-10 by itself could not promote the proliferation of CD8⁺ T cells but could significantly enhance IL-2-mediated promotion of CD8⁺ T cell proliferation. In addition, the cytotoxicity of tumor-infiltrating CD8⁺ T cells in breast tumor was elevated when both IL-2 and IL-10 were present but not when either one was absent. This synergistic effect was stopped by CD4⁺CD25⁺ regulatory T cells (Treg), which depleted IL-2 in a cell number-dependent manner. Together, these results demonstrated that IL-2 and IL-10 could work synergistically to improve the survival, proliferation, and cytotoxicity of activated CD8⁺ T cells, an effect suppressible by CD4⁺CD25⁺ Treg cells.     

Expression profile of IL-8 and growth factors in breast cancer cells and adipose-derived stem cells (ASCs) isolated from breast carcinoma

Adipose-derived stem cells (ASCs) are regarded as a major player of breast cancer microenvironment. By production of various growth factors and expression of regulatory molecules, it is postulated that ASCs protect breast cancer cells from the host immune responses. In this study, the expressions of insulin-like growth factor-1 (IGF-1), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), CXCL8 (IL-8) in breast cancer cells and adipose-derived stem cells isolated from breast tissue of women with breast cancer were investigated. The results were analyzed comparatively in normal ASCs isolated from healthy normal women. In case of breast cancer tissues, results were analyzed between high stage and low stage patients. The expressions of extracted mRNAs were determined using real-time quantitative RT-PCR. As a result, in breast cancer tissues, IGF-1 and IL-8 mRNAs had 28.6 and 56-fold more expressions in high stage compared to low stage patients. In ASCs, relative quantifications (RQ) of VEGF, IL-8, HGF and IGF-1 was about 2-fold higher in patients than controls. Data of this study conclude that presence of resident ASCs within the scaffold of breast tissue may support breast tumor growth and progression through the expressions of tumor promoting factors.     

Dendritic cells are dysfunctional in patients with operable breast cancer

Background: Dendritic cells (DCs) play a crucial role in presenting antigens to T lymphocytes and inducing cytotoxic T cells. DCs have been studied in patients with breast cancer to define the factors leading to failure of an effective systemic and locoregional anticancer host response. Methods: Purified DCs were obtained from peripheral blood (PB) and lymph nodes (LNs) of women with operable breast cancer, using immunomagnetic bead selection. The stimulatory capacity of DCs in the allogeneic mixed leukocyte reaction (MLR) and autologous T cell proliferation test (purified protein derivative (PPD) as stimulator), the expression of surface markers on DCs and the production of cytokines in vitro by DCs from patients with operable breast cancer and from healthy donors (controls) were studied. Results: 70–75% purified DCs were isolated from PB and LNs. PBDCs and LNDCs from patients with operable breast cancer demonstrated a reduced capacity to stimulate in an MLR, compared with PBDCs from normal donors (p<0.01). Autologous T cell proliferation in patients had a decreased ability to respond to PPD, when compared with controls (p<0.01). However, T cells from patients responded as well as control T lymphocytes in the presence of control DCs. PBDCs and LNDCs from patients expressed low levels of HLA-DR and CD86, and induced decreased interleukin-12 (IL-12) secretion in vitro, compared with DCs from normal donors (p<0.01). Conclusion: These data suggest a defective DC function in patients with operable breast cancer. Switched-off DCs in patients with early breast cancer and decreased IL-12 production may be important factors for progressive tumour growth.     

Cellular interaction against autologous tumor cells between IL-2-cultured lymphocytes and fresh peripheral blood lymphocytes in patients with breast cancer given immuno-chemotherapy

In patients with Stage II or III breast cancer and in patients with liver metastases from breast cancer, we examined cellular interaction in the cytotoxicity against autologous tumor cells by interleukin-2(IL-2)-cultured lymphocytes (CL) and fresh peripheral blood lymphocytes (FPBL) treated with immunochemotherapy including OK-432 and cyclophosphamide. In flow cytometric analysis, CD8 + CD11b+ and CD16+ cells significantly decreased after immuno-chemotherapy in both groups of patients. A protocol study in Stage II or III breast cancer patients showed suppressive activity of FPBL on the cytotoxic activity of CL in 3/9 of the non-treatment group but no suppressive activity and enhancing activity in 3/7 in the immuno-chemotherapy group. Moreover, in 19 patients with liver metastases from breast cancer treated with immuno-chemotherapy including adoptive immunotherapy, FPBL in 6/19 showed enhancing activity, and in 8/19 suppressive activity in the lysis of autologous tumor cells. In assaysin vitro using autologous and allogeneic tumor cells, FPBL showed a partial specificity in cellular interaction against autologous tumor cells. CD4-depleted FPBL inhibited cytotoxicity of CL, while CD8-depleted FPBL enhanced cytotoxicity of CL in patients with liver metastases. These results suggest that immuno-chemotherapy eliminates the suppressive population in FPBL and may induce tumor regression if combined with adoptive immunotherapy using CL.Abbreviations IL-2 interleukin-2 - CL IL-2-cultured lymphocytes - FPBL fresh peripheral blood lymphocytes - AIT adoptive immunotherapy     

Matrix Metalloproteinase 8 (Collagenase 2) Induces the Expression of Interleukins 6 and 8 in Breast Cancer Cells

Matrix metalloproteinase 8 (MMP-8) is a tumor-suppressive protease that cleaves numerous substrates, including matrix proteins and chemokines. In particular, MMP-8 proteolytically activates IL-8 and, thereby, regulates neutrophil chemotaxis in vivo. We explored the effects of expression of either a WT or catalytically inactive (E198A) mutant version of MMP-8 in human breast cancer cell lines. Analysis of serum-free conditioned media from three breast cancer cell lines (MCF-7, SK-BR-3, and MDA-MB-231) expressing WT MMP-8 revealed elevated levels of IL-6 and IL-8. This increase was mirrored at the mRNA level and was dependent on MMP-8 catalytic activity. However, sustained expression of WT MMP-8 by breast cancer cells was non-permissive for long-term growth, as shown by reduced colony formation compared with cells expressing either control vector or E198A mutant MMP-8. In long-term culture of transfected MDA-MB-231 cells, expression of WT but not E198A mutant MMP-8 was lost, with IL-6 and IL-8 levels returning to base line. Rare clonal isolates of MDA-MB-231 cells expressing WT MMP-8 were generated, and these showed constitutively high levels of IL-6 and IL-8, although production of the interleukins was no longer dependent upon MMP-8 activity. These studies support a causal connection between MMP-8 activity and the IL-6/IL-8 network, with an acute response to MMP-8 involving induction of the proinflammatory mediators, which may in part serve to compensate for the deleterious effects of MMP-8 on breast cancer cell growth. This axis may be relevant to the recognized ability of MMP-8 to orchestrate the innate immune system in inflammation in vivo.     

Expression of interleukin-2 receptor by activated peripheral blood lymphocytes upregulated by the plasma level of interleukin-2 in patients with recurrent aphthous ulcers

This study used flow cytometry to determine the peripheral blood lymphocyte subsets and a sandwich enzyme immunoassay to measure the plasma levels of interleukin-2 (IL-2) and soluble IL-2 receptor (sIL-2R) in 34 patients in different stages of recurrent aphthous ulcers (RAU) and in 32 age/sex-matched normal control subjects. In the exacerbation stage of RAU, a significant increase in the percentages of CD3+ (p < 0.001), CD4+ (p < 0.001), CD4+ IL-2R+ (p < 0.001), CD8+ IL-2R+ (p < 0.01) and IL-2R+ cells (p < 0.001), in the CD4+/CD8+ (p < 0.01) and CD4+/CD3+ CD8+ ratios (p < 0.01), and in the plasma level of IL-2 (p < 0.001) was found in the patients as compared with the levels in the normal control subjects. However, in the post-exacerbation stage of RAU, there was a significant decrease in the percentage of CD4+ cells (p < 0.05) and in the CD4+/CD8+ (p < 0.01) and CD4+/CD3+ CD8+ ratios (p < 0.001), as well as a significant increase in CD8+ cells (p < 0.001) in the patients, as compared with the levels in the normal control subjects. Because the CD4+, CD4+ IL-2R+ and CD8+ IL-2R+ cell counts and the plasma level of IL-2 increased simultaneously in the patients in the exacerbation stage of RAU, we suggest that the markedly increased plasma level of IL-2 may have been secreted by the increased number of activated CD4+ cells, and that the expression of IL-2R by activated peripheral blood lymphocytes was upregulated by the plasma level of IL-2 in patients with RAU. In addition, the increase and then decrease of the CD4+/CD8+ ratio in the RAU patients and the increased number of CD4+ IL-2R+ and CD8+ IL-2R+ activated T cells in the RAU patients support the role of cell-mediated cytotoxicity in the immunopathogenesis of RAU.     

Adipose derived stem cells (ASCs) isolated from breast cancer tissue express IL-4, IL-10 and TGF-β1 and upregulate expression of regulatory molecules on T cells: do they protect breast cancer cells from the immune response?

Immunomodulatory function of bone marrow derived mesenchymal stem cells in cancer has recently been investigated. But the resident mesenchymal stem cells as whole in cancer and in the breast cancer tissue have not been studied well. In the present work we isolated adipose derived stem cells (ASCs) from breast cancer and normal breast tissues to investigate the expressions of IL-4, IL-10 and transforming growth factor (TGF)-β1 in ASCs and to see if ASCs isolated from patients can modulate the regulatory molecules on peripheral blood lymphocytes. Our results showed that IL-10 and TGF-β1 have significantly higher mRNA expressions in ASCs isolated from breast cancer patients than those from normal individuals (P value <0.05). The culture supernatant of ASCs isolated from breast cancer patients with pathological stage III induced upregulation of the mRNA expression levels of IL-4, TGF-β1, IL-10, CCR4 and CD25 in PBLs. In addition, the percentage of CD4+CD25^highFoxp3⁺ T regulatory cells was increased in vitro. When the same culture supernatant was added to ASCs isolated from normal subjects augmentation of the mRNA expressions of IL-4, IL-10, IL-8, MMP2, VEGF and SDF-1 in normal ASCs was also observed. These data collectively conclude that resident ASCs in breast cancer tissue may have crucial roles in breast tumor growth and progression by inducing regulatory molecules and promoting anti-inflammatory reaction within the tumor microenvironment. Further investigation is required to see if the immune suppression induced by ASCs is an independent property from tumor cells or ASCs gain their immunosuppressive potential from malignant cells.     

Expression of Th17 cells in breast cancer tissue and its association with clinical parameters

Th17 cells are newly identified effector CD4⁺ T cells, which play an active role in inflammation and autoimmune diseases and may be relevant for anti-tumor defenses. In the present study, we examined expression of Th17 cells in specimens of breast cancer tissue and its association with clinical, pathology, and immunological parameters. Expression rates of Th17 and T regulatory (Treg) cells in breast cancer and normal (i.e. non-cancerous) tissue were evaluated using flow cytometry in 30 patients with breast carcinoma. Further, expression of interleukin-17 (IL-17), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in breast cancer tissue was evaluated by immunohistochemical staining. Associations between Th17 expression and other parameters were analyzed by multiple linear regression analysis. We observed that expression of Th17 cells was significantly higher in breast cancer compared to normal breast tissue. Further, expressions of IL-17, IL-1β, and IL-6 in cancer tissue positively correlated with expression of Th17 cells. In addition, there was a negative association between the numbers of Th17 cells and TNM stage, blood vessel invasion, and increased numbers of metastatic lymph nodes. Finally, expression of Th17 was not associated with expression of Treg. In conclusion, Th17 cells appear to be involved in anti-tumor immune responses and are associated with a more favorable prognosis.     

Basal-like breast cancer cells induce phenotypic and genomic changes in macrophages

Basal-like breast cancer (BBC) is an aggressive subtype of breast cancer that has no biologically targeted therapy. The interactions of BBCs with stromal cells are important determinants of tumor biology, with inflammatory cells playing well-recognized roles in cancer progression. Despite the fact that macrophage-BBC communication is bidirectional, important questions remain about how BBCs affect adjacent immune cells. This study investigated monocyte-to-macrophage differentiation and polarization and gene expression in response to coculture with basal-like versus luminal breast cancer cells. Changes induced by coculture were compared with changes observed under classical differentiation and polarization conditions. Monocytes (THP-1 cells) exposed to BBC cells in coculture had altered gene expression with upregulation of both M1 and M2 macrophage markers. Two sets of M1 and M2 markers were selected from the PCR profiles and used for dual immunofluorescent staining of BBC versus luminal cocultured THP-1s, and cancer-adjacent, benign tissue sections from patients diagnosed with BBCs or luminal breast cancer, confirming the differential expression patterns. Relative to luminal breast cancers, BBCs also increased differentiation of monocytes to macrophages and stimulated macrophage migration. Consistent with these changes in cellular phenotype, a distinct pattern of cytokine secretion was evident in macrophage-BBC cocultures, including upregulation of NAP-2, osteoprotegerin, MIG, MCP-1, MCP-3, and interleukin (IL)-1β. Application of IL-1 receptor antagonist (IL-1RA) to cocultures attenuated BBC-induced macrophage migration. These data contribute to an understanding of the BBC-mediated activation of the stromal immune response, implicating specific cytokines that are differentially expressed in basal-like microenvironments and suggesting plausible targets for modulating immune responses to BBCs.     

A Novel 3-D Mineralized Tumor Model to Study Breast Cancer Bone Metastasis

Background

Metastatic bone disease is a frequent cause of morbidity in patients with advanced breast cancer, but the role of the bone mineral hydroxyapatite (HA) in this process remains unclear. We have developed a novel mineralized 3-D tumor model and have employed this culture system to systematically investigate the pro-metastatic role of HA under physiologically relevant conditions in vitro.

Methodology/Principal Findings

MDA-MB231 breast cancer cells were cultured within non-mineralized or mineralized polymeric scaffolds fabricated by a gas foaming-particulate leaching technique. Tumor cell adhesion, proliferation, and secretion of pro-osteoclastic interleukin-8 (IL-8) was increased in mineralized tumor models as compared to non-mineralized tumor models, and IL-8 secretion was more pronounced for bone-specific MDA-MB231 subpopulations relative to lung-specific breast cancer cells. These differences were pathologically significant as conditioned media collected from mineralized tumor models promoted osteoclastogenesis in an IL-8 dependent manner. Finally, drug testing and signaling studies with transforming growth factor beta (TGFβ) confirmed the clinical relevance of our culture system and revealed that breast cancer cell behavior is broadly affected by HA.

Conclusions/Significance

Our results indicate that HA promotes features associated with the neoplastic and metastatic growth of breast carcinoma cells in bone and that IL-8 may play an important role in this process. The developed mineralized tumor models may help to reveal the underlying cellular and molecular mechanisms that may ultimately enable more efficacious therapy of patients with advanced breast cancer.     

Clinical therapeutic effect of adoptive immunotherapy using IL-2-cultured autologous lymphocytes

Our method of adoptive immunotherapy (AIT) using autologous IL-2-cultured lymphocytes differs from so-called LAK therapy in several points. We (1) obtain cultured lymphocytes from effusion lymphocytes (EL) or regional lymph-node lymphocytes (RLNL), when possible, rather than peripheral blood lymphocytes (PBL), (2) use crude IL-2 to induce T cell proliferation and to maintain killer activity, (3) use sonicated autologous tumor extract as antigen (Ag) to stimulate proliferation of cytotoxic T cells, and (4) pretreat the patients with local administration of OK-432 before AIT to induce effector cells that act synergistically with transferred killer cells. Surface marker analysis showed that OKT3, IL-2 receptor, Leu 2+15- cells were elevated while Leu 11a and Leu 3+8+ cells were decreased. Culture of RLNL augmented the expression of Leu 3+8- marker. Both of PBL and RLNL responded to Ag, and their auto-tumor killing activities were augmented in about half of the patients while rarely decrease by the addition of Ag. Response rates of patients with pleural effusion due to breast cancer and those with liver metastasis of breast cancer were 94% and 60%, respectively. Moreover, the survival was prolonged in the treated patients with pleural effusion or gastric cancer patients with peritoneal dissemination.     

lncRNA DILC is downregulated in osteoarthritis and regulates IL-6 expression in chondrocytes

Excessive production of interleukin 6 (IL-6) is involved in the pathogenesis of osteoarthritis. It has been reported that long noncoding RNA (lncRNA) DILC inhibited IL-6 to regulate liver cancer stem cells. Therefore, lncRNA DILC may also participate in osteoarthritis. We found that lncRNA DILC was downregulated, while IL-6 was upregulated in plasma of osteoarthritis patients comparing to the control group. Levels of plasma lncRNA DILC and IL-6 were significantly and inversely correlated only in patients with osteoarthritis. Downregulation of lncRNA DILC effectively distinguished patients with osteoarthritis from the control group. Overexpression of lncRNA DILC resulted in inhibited IL-6 expression in chondrocytes, while treatment with exogenous IL-6 did not affect lncRNA DILC expression. However, lncRNA DILC overexpression did not affect the proliferation and apoptosis of chondrocytes. Therefore, lncRNA DILC is downregulated in osteoarthritis and regulates IL-6 expression in chondrocytes.     

Elevated level of peripheral CD8+CD28− T lymphocytes are an independent predictor of progression-free survival in patients with metastatic breast cancer during the course of chemotherapy

Purpose

Suppression of cellular immunity resulting from tumorigenesis and/or therapy might promote cancer cells’ growth, progression and invasion. Here, we explored whether T lymphocyte subtypes from peripheral blood of metastatic breast cancer (MBC) female patients could be used as alternative surrogate markers for cancer progress. Additionally, plasma levels of interleukin (IL)-2, IL-4, IL-6, IL-10, IFN-γ, and transforming growth factor-β1 were quantitated from MBC and healthy volunteers.

Experimental design

This study included 89 female MBC patients during the post-salvage chemotherapy follow-up and 50 age- and sex-matched healthy volunteers as control. The percentages of T lymphocyte subpopulations from peripheral blood and plasma levels of cytokines were measured.

Results

Both CD8⁺CD28^? and CD4⁺CD25⁺ were elevated in MBC patients compared to the control cohort (P < 0.05). In contrast, CD3⁺ and CD8⁺CD28⁺cells were significantly lower in MBC patients (P < 0.0001, P = 0.045, respectively). MBC patients had elevated levels of immunosuppressive cytokines IL-6 and IL-10. Patients with elevated CD8⁺CD28^? and CD4⁺CD25⁺ cells showed increased levels of IL-6, and only patients with elevated CD8⁺CD28^? had decreased interferon-γ. Univariate analysis indicated increased CD3⁺CD4⁺ or CD8⁺CD28⁺correlated with prolonged progression-free survival (PFS), while elevated CD8⁺CD28^?associated with shorten PFS. The percent of CD8⁺CD28^? T lymphocytes is an independent predictor for PFS through multivariate analysis.

Conclusions

This study suggests that progressive elevated levels of CD8⁺CD28^? suppressor T lymphocytes represent a novel independent predictor of PFS during post-chemotherapy follow-up.