Key Points: ECs express Tlr4 and Myd88 and, after in vivo LPS or E coli stimulation, are the prime sources of G-CSF. ECs are sensors of systemically spread pathogens and subsequent drivers of BM emergency granulopoiesis.

Background: With the aim to simplify cancer management, cancer research lately dedicated itself more and more to discover and develop non-invasive biomarkers. In this connection, circulating cell-free DNA (ccf DNA) seems to be a promising candidate. Altered levels of ccf nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) have been found in several cancer types and might have a diagnostic value. Methods: Using multiplex real-time PCR we investigated the levels of ccf nDNA and mtDNA in plasma samples from patients with malignant and benign breast tumors, and from healthy controls. To evaluate the applicability of plasma ccf nDNA and mtDNA as a biomarker for distinguishing between the three study-groups we performed ROC (Receiver Operating Characteristic) curve analysis. We also compared the levels of both species in the cancer group with clinicopathological parameters. Results: While the levels of ccf nDNA in the cancer group were significantly higher in comparison with the benign tumor group (P < 0.001) and the healthy control group (P < 0.001), the level of ccf mtDNA was found to be significantly lower in the two tumor-groups (benign: P < 0.001; malignant: P = 0.022). The level of ccf nDNA was also associated with tumor-size (2 cm<5 cm; 2250 vs. 6658; Mann-Whitney-U-Test: P = 0.034). Using ROC curve analysis, we were able to distinguish between the breast cancer cases and the healthy controls using ccf nDNA as marker (cut-off: 1866 GE/ml; sensitivity: 81%; specificity: 69%; P < 0.001) and between the tumor group and the healthy controls using ccf mtDNA as marker (cut-off: 463282 GE/ml; sensitivity: 53%; specificity: 87%; P < 0.001). Conclusion: Our data suggests that nuclear and mitochondrial ccf DNA have potential as biomarkers in breast tumor management. However, ccf nDNA shows greater promise regarding sensitivity and specificity.

Aberrant proliferation, symmetric self-renewal, increased survival, and defective differentiation of malignant blasts are key oncogenic drivers in acute myeloid leukemia (AML). Stem cell gene signatures predict poor prognosis in AML patients; however, with few exceptions, these deregulated molecular pathways cannot be targeted therapeutically. In this study, we demonstrate that the TNF superfamily ligand–receptor pair CD70/CD27 is expressed on AML blasts and AML stem/progenitor cells. CD70/CD27 signaling in AML cells activates stem cell gene expression programs, including the Wnt pathway, and promotes symmetric cell divisions and proliferation. Soluble CD27, reflecting the extent of CD70/CD27 interactions in vivo, was significantly elevated in the sera of newly diagnosed AML patients and is a strong independent negative prognostic biomarker for overall survival. Blocking the CD70/CD27 interaction by mAb induced asymmetric cell divisions and differentiation in AML blasts and AML stem/progenitor cells, inhibited cell growth and colony formation, and significantly prolonged survival in murine AML xenografts. Importantly, hematopoietic stem/progenitor cells from healthy BM donors express neither CD70 nor CD27 and were unaffected by blocking mAb treatment. Therefore, targeting CD70/CD27 signaling represents a promising therapeutic strategy for AML.

To analyze the levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in patients with benign and malignant ovarian tumors using a gold-standard assay and to investigate whether quantitative alterations of the circulating cell-free species have values in the management of the patients. One hundred four patients were recruited for this study. We developed a quantitative, multiplex polymerase chain reaction to measure the levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in serum and plasma of patients with epithelial ovarian cancer, benign epithelial ovarian tumors, or endometriosis. The levels of the circulating cell-free DNA were compared with those of a healthy, age-matched control group. The patients with epithelial ovarian cancer had significantly higher amounts of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in plasma compared with the healthy control group (mean of nuclear DNA 10,723/2,591 and mean of mitochondrial DNA 4,918,978/2,294,264, P=.009 and 0.022, respectively) and with the other group with benign ovarian diseases (mean of nuclear DNA 10,723/2,965 and mean of mitochondrial DNA 4,918,978/1,597,551, P=.027 and 0.002, respectively). However, no relationship between levels of the circulating cell-free DNA and the pathological parameters as well as CA 125 measurement in patients with epithelial ovarian cancer was found. A significant difference between the epithelial ovarian cancer and endometriosis group was found in circulating cell-free mitochondrial DNA but not in circulating cell-free nuclear DNA (mean of mitochondrial DNA 4,918,978/2,273,988 and mean of nuclear DNA 10,723/3,291, P=.013 and 0.105, respectively). Elevated levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in epithelial ovarian cancer may have diagnostic value. Our finding suggests that the circulating molecules might be potential biomarkers in the disease.

Aberrant DNA methylation patterns might be used as a biomarker for diagnosis and management of cancer patients. To achieve a gene panel for developing a breast cancer blood-based test we quantitatively assessed the DNA methylation proportion of 248 CpG sites per sample (total of 31,248 sites in all analyzed samples) on 10 candidate genes (APC, BIN1, BMP6, BRCA1, CST6, ESR-b, GSTP1, P16, P21 and TIMP3). The number of 126 samples consisting of two different cohorts was used (first cohort: plasma samples from breast cancer patients and normal controls; second cohort: triple matched samples including cancerous tissue, matched normal tissue and serum samples). In the first cohort, circulating cell free methylated DNA of the 8 tumor suppressor genes (TSGs) was significantly higher in patients with breast cancer compared to normal controls (P<0.01). In the second cohort containing triple matched samples, seven genes showed concordant hypermethylated profile in tumor tissue and serum samples compared to normal tissue (P<0.05). Using eight genes as a panel to develop a blood-based test for breast cancer, a sensitivity and specificity of more than 90% could be achieved in distinguishing between tumor and normal samples. Our study suggests that the selected TSG panel combined with the high-throughput technology might be a useful tool to develop epigenetic based predictive and prognostic biomarker for breast cancer relying on pathologic methylation changes in tumor tissue, as well as in circulation.