Circulating Tumor Cells With Epithelial-to-mesenchymal Transition Phenotypes Associated With Inferior Outcomes in Primary Breast Cancer.

BACKGROUND/AIM: Circulating tumor cells (CTCs) comprise a heterogeneous population of cancer cells with different clinical and biological value. The aim of this study was to evaluate the prognostic value of CTCs with an epithelial-mesenchymal transition (EMT) phenotype in primary breast cancer (PBC) patients. PATIENTS AND METHODS: This study included 427 primary breast cancer patients. RNA extracted from CD45-depleted peripheral blood mononuclear cell (PBMCs) was evaluated for the expression of EMT transcription factors (TWIST1, SNAIL1, SLUG, ZEB1) by quantitative real time polymerase chain reaction (qRT-PCR). RESULTS: In total, CTC EMT was detected in 77 (18.0%) patients. Patients without detectable CTC EMT in peripheral blood had significantly longer disease-free survival than patients with detectable CTC EMT. The prognostic value of CTC EMT was demonstrated in all subgroups of patients. CONCLUSION: CTCs with an EMT phenotype have a prognostic value in primary breast cancer.

Prognostic value of various subtypes of extracellular DNA in ovarian cancer patients.

BACKGROUND: Patients with ovarian cancer represent a heterogeneous population with a variable prognosis and response to chemotherapy. Plasma DNA has been shown to have a prognostic value in different types of cancer including ovarian carcinoma. Whether total circulating DNA, which can be assessed much easier without knowing the tumor-specific mutations, has similar informative value is currently unknown. The aim of this study was to evaluate the prognostic value of extracellular DNA in advanced ovarian cancer. METHODS: This prospective study included 67 patients (pts) with ovarian cancer treated with 1st line paclitaxel and carboplatin (25 pts) and paclitaxel, carboplatin and bevacizumab (42 pts). Thirty-five patients had optimal surgical debulking before chemotherapy. Extracellular DNA was quantified using real time PCR before administration of chemotherapy (67 pts) and after 6 cycles of chemotherapy (44 pts). RESULTS: Total extracellular DNA (ecDNA), as well as extracellular DNA of nuclear (nDNA) and mitochondrial origin (mtDNA) significantly (p < 0.05) decreased after 6 cycles of chemotherapy (by 54%, 63% and 52%, respectively. Patients with stage I disease had significantly lower mtDNA compared to patients with stage II-IV (8604 vs. 16, 984 ge/mL, p = 0.03). Patients with lower baseline nDNA had superior progression-free (HR = 0.35 (0.14-0.86)) and overall survival (HR = 0.18 (0.04-0.77). The prognostic value of nDNA was confirmed independent of tumor stage and confirmed in multivariate analysis. CONCLUSIONS: Our data suggest that ecDNA of both, nuclear and mitochondrial origin could be added to prognostic markers in ovarian cancer. Analysis of ecDNA does not require the knowledge of tumor-specific mutations in contrast to the quantification of tumor-derived ecDNA. Study of the dynamics and cell type-specific source of the ecDNA could shed light on its biology in cancer and might help to direct the treatment of ovarian cancer.

Relationship Between Circulating Tumor Cells and Tissue Plasminogen Activator in Patients with Early Breast Cancer.

AIM: Cancer increases the risk of venous thromboembolism (VTE) and circulating tumor cells (CTCs) are associated with an increased risk of VTE and, thus, with increased D-dimers as a product of fibrinolysis. Tissue plasminogen activator (tPA) is one of the key enzymes in the fibrinolytic pathway. Its activity is crucial in maintaining the balance between blood coagulation and fibrinolysis. This study aimed to analyze the association between CTCs and tPA in patients with primary breast cancer before surgery. PATIENTS AND METHODS: This prospective study included 110 patients in whom CTCs were detected by quantitative reverse transcription polymerase chain reaction targeted at epithelial (CK19) or epithelial-mesenchymal transition (EMT)-associated genes[TWIST1, SNAI1, SNAI2, zinc finger E-box-binding homeobox 1 (ZEB1), forkhead box protein C2 (FOXC2)]. Plasma tPA protein was detected using enzyme-linked immunosorbent assay (ELISA). RESULTS: CTCs were detected in 31 (28.2%) patients. There was no association between plasma tPA and CTCs. Although on average, higher levels of tPA were detected in patients with CTCs expressing EMT-associated genes, this difference did not reach statistical significance. There was no association of plasma tPA with any of the observed patient or tumor characteristics. CONCLUSION: Even though the blood coagulation pathway may be activated in more aggressive disease related to an elevated CTC count, in this study, we did not find any association between CTCs and plasma concentrations of tPA.

Matrix metalloproteinase 1 and circulating tumor cells in early breast cancer.

BACKGROUND: Matrix metalloproteinases (MMPs) are involved in cancer invasion and metastasis. Circulating tumor cells (CTCs) play role in tumor dissemination and are an independent survival predictor in breast cancer (BC) patients. The aim of this study was to assess correlation between CTCs and tumor MMP1 in BC. METHODS: Study included 149 primary BC patients treated by surgery from March 2012 to March 2013. Peripheral blood mononuclear cells (PBMC) were depleted of hematopoietic cells using RossetteSep(TM) selection kit. RNA extracted from CD45-depleted PBMC was interrogated for expression of EMT (TWIST1, SNAIL1, SLUG, ZEB1) and epithelial (CK19) gene transcripts by qRT-PCR. Patient samples with higher epithelial and/or mesenchymal gene transcripts than those of healthy donors (n = 60) were considered as CTC positive. Expression of MMP1 in surgical specimens was evaluated by immunohistochemistry. RESULTS: CTCs were detected in 24.2% patients. CTCs exhibiting only epithelial markers were present in 8.7% patients, whereas CTCs with epithelial-mesenchymal transition (EMT) markers (CTC_EMT) were observed in 13.4% of patients and CTCs co-expressing both markers were detected in 2.0% patients. Patients with CTC_EMT in peripheral blood had significantly increased expression of MMP1 in tumor cells (p = 0.02) and tumor associated stroma (p = 0.05) than those of patients without CTC_EMT. In multivariate analysis, CTC_EMT and tumor grade were independently associated with MMP1 expression in cancer cells, while CTC_EMT and Ki67 were independently associated with MMP1 expression in cancer associated stroma. CONCLUSION: Our data suggest link between MMP1 and CTCs with EMT phenotype and support role of MMPs and EMT in tumor dissemination.