Circulating tumor cells detection in tumor draining vein of breast cancer patients

Clinical Implications of Circulating Tumor Cells in Patients with Esophageal Squamous Cell Carcinoma: Cancer-Draining Blood Versus Peripheral Blood

Circulating tumor cells (CTCs) in cancer-draining veins have diagnostic and prognostic value. However, studies on esophageal squamous cell carcinoma (ESCC) are limited. This study aimed to compare CTCs obtained from different sampling sites (peripheral vein vs. cancer-draining azygos vein) and to investigate their association with the clinicopathological characteristics of ESCC patients. Blood samples were collected preoperatively from both veins in 40 ESCC patients at Pusan National University Hospital from June 2020 to April 2022. CTCs were detected using a centrifugal microfluidic method with fluid-assisted separation. CTCs and TWIST (+) CTCs were detected more frequently in the azygos vein blood than in the peripheral vein blood; however, the difference was not statistically significant (85.0% [34/40] vs. 77.5% [31/40], p = 0.250 and 82.5% [33/40] vs. 75.0% [30/40], p = 0.586, respectively). CTC and TWIST (+) CTC counts were significantly higher in the azygos vein blood than in the peripheral vein blood (7 vs. 3, p < 0.001, and 6 vs. 2, p < 0.001, respectively). CTCs and TWIST (+) CTCs from peripheral and azygos veins showed no association with clinicopathological characteristics. Further large-scale studies are needed to clarify their role as predictive biomarkers for prognosis and chemotherapy responses in ESCC patients.

Predictive value of circulating tumor cell counts during the treatment of cancer: interactions with the blood microenvironment

OBJECTIVE

This study aimed to evaluate the prognostic value of circulating tumor cell (CTC) in tumor patients during treatment.

METHODS

This study retrospectively analyzed clinical data obtained from 174 cancer patients during treatment. The relationship between the CTC counts and clinicopathological variables was analyzed. A ROC curve was applied to determine the optimal cut-off values and assess the predictive ability of the prognostic indicators. The overall survival (OS) for different prognostic factors was calculated using the Kaplan-Meier method, and the difference between the survival curves was then compared using the log-rank test. Cox regression model was used to investigate the effect of independent factors on patients' survival.

RESULTS

The CTC-positive rate was positively correlated with the clinicopathological variables of TNM stage, tumor differentiation, serum CEA level, and ki-67%. In the differential analysis of hematological microenvironment parameters in CTC-positive and CTC-negative samples, the complete blood count, blood biological chemistry, tumor markers (CEA, CA19-9, CA72-4), and lymphocyte subpopulation were statistically significant. The results of the ROC curve analysis indicated that the serum CEA level was the best diagnostic indicator to discriminate the CTC count in tumor patients. Additionally, the results of the univariate and multivariate analyses of OS in relation to clinical variables revealed that the CTC counts were an independent prognostic factor for unfavorable OS.

CONCLUSION

The CTC counts in patients with tumors undergoing treatment were significantly correlated with hematological microenvironment parameters. The detection of CTCs may therefore be used as an indicator of tumor prognosis.

Endovascular image-guided sampling of tumor-draining veins provides an enriched source of oncological biomarkers

Introduction

Circulating tumor-derived biomarkers can potentially impact cancer management throughout the continuum of care. This small exploratory study aimed to assess the relative levels of such biomarkers in the tumor-draining vascular beds in patients with solid tumors compared to levels in their peripheral veins.

Methods

Using an endovascular image-guided approach, we obtained blood samples from peripheral veins and other vascular compartments–including the most proximal venous drainage from solid tumors–from a set of nine oncology patients with various primary and metastatic malignancies. We then interrogated these samples for a panel of oncological biomarkers, including circulating tumor cells (CTCs), exosome-derived microRNAs (miRNAs), circulating tumor DNA (ctDNA) mutations, and certain cancer-related proteins/biochemical markers.

Results

We found substantially higher levels of CTCs, certain miRNAs, and specific ctDNA mutations in samples from vascular beds closer to the tumor compared with those from peripheral veins and also noted that some of these signals were altered by treatment procedures.

Discussion

Our results indicate that tumor-proximal venous samples are highly enriched for some oncological biomarkers and may allow for more robust molecular analysis than peripheral vein samples.

Heterodimeric IL-15 (hetIL-15) reduces circulating tumor cells and metastasis formation improving chemotherapy and surgery in 4T1 mouse model of TNBC

Immunotherapy has emerged as a viable approach in cancer therapy, with cytokines being of great interest. Interleukin IL-15 (IL-15), a cytokine that supports cytotoxic immune cells, has been successfully tested as an anti-cancer and anti-metastatic agent, but combinations with conventional chemotherapy and surgery protocols have not been extensively studied. We have produced heterodimeric IL-15 (hetIL-15), which has shown anti-tumor efficacy in several murine cancer models and is being evaluated in clinical trials for metastatic cancers. In this study, we examined the therapeutic effects of hetIL-15 in combination with chemotherapy and surgery in the 4T1 mouse model of metastatic triple negative breast cancer (TNBC). hetIL-15 monotherapy exhibited potent anti-metastatic effects by diminishing the number of circulating tumor cells (CTCs) and by controlling tumor cells colonization of the lungs. hetIL-15 treatment in combination with doxorubicin resulted in enhanced anti-metastatic activity and extended animal survival. Systemic immune phenotype analysis showed that the chemoimmunotherapeutic regimen shifted the tumor-induced imbalance of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in favor of cytotoxic effector cells, by simultaneously decreasing PMN-MDSCs and increasing the frequency and activation of effector (CD8⁺T and NK) cells. Tumor resection supported by neoadjuvant and adjuvant administration of hetIL-15, either alone or in combination with doxorubicin, resulted in the cure of approximately half of the treated animals and the development of anti-4T1 tumor immunity. Our findings demonstrate a significant anti-metastatic potential of hetIL-15 in combination with chemotherapy and surgery and suggest exploring the use of this regimen for the treatment of TNBC.

Characterization of the MicroRNA Cargo of Extracellular Vesicles Isolated from a Pulmonary Tumor-Draining Vein Identifies miR-203a-3p as a Relapse Biomarker for Resected Non-Small Cell Lung Cancer

In resected non-small cell lung cancer (NSCLC), post-surgical recurrence occurs in around 40% of patients, highlighting the necessity to identify relapse biomarkers. An analysis of the extracellular vesicle (EV) cargo from a pulmonary tumor-draining vein (TDV) can grant biomarker identification. We studied the pulmonary TDV EV-miRNAome to identify relapse biomarkers in a two-phase study (screening and validation). In the screening phase, a 17-miRNA relapse signature was identified in 18 selected patients by small RNAseq. The most expressed miRNA from the signature (EV-miR-203a-3p) was chosen for further validation. Pulmonary TDV EV-miR-203a-3p was studied by qRT-PCR in a validation cohort of 70 patients, where it was found to be upregulated in relapsed patients (p = 0.0194) and in patients with cancer spread to nearby lymph nodes (N+ patients) (p = 0.0396). The ROC curve analysis showed that TDV EV-miR-203a-3p was able to predict relapses with a sensitivity of 88% (AUC: 0.67; p = 0.022). Moreover, patients with high TDV EV-miR-203a-3p had a shorter time to relapse than patients with low levels (43.6 vs. 97.6 months; p = 0.00703). The multivariate analysis showed that EV-miR-203a-3p was an independent, predictive and prognostic post-surgical relapse biomarker. In conclusion, pulmonary TDV EV-miR-203a-3p is a promising new relapse biomarker for resected NSCLC patients.

Breast Cancer Cells Metastasize to the Tissue-Engineered Premetastatic Niche by Using an Osteoid-Formed Polycaprolactone/Nanohydroxyapatite Scaffold

It has been deemed that the premetastatic niche (PMN) plays a critical role in facilitating bone metastasis of breast cancer cells. Tissue engineering scaffolds provide an advantageous environment to promote osteogenesis that may mimic the bony premetastatic niches (BPMNs). In this study, human mesenchymal stem cells (hMSCs) were seeded onto designed polycaprolactone/nanohydroxyapatite (PCL-nHA) scaffolds for osteogenic differentiation. Subsequently, a coculture system was used to establish the tissue-engineered BPMNs by culturing breast cancer cells, hMSCs, and osteoid-formed PCL-nHA scaffolds. Afterwards, a migration assay was used to investigate the recruitment of MDA-MB-231, MCF-7, and MDA-MB-453 cells to the BPMNs' supernatants. The cancer stem cell (CSC) properties of these migrated cells were investigated by flow cytometry. Our results showed that the mRNA expression levels of alkaline phosphatase (ALP), Osterix, runt-related transcription factor 2 (Runx2), and collagen type I alpha 1 (COL1A1) on the PCL-nHA scaffolds were dramatically increased compared to the PCL scaffolds on days 11, 18, and 32. The expression of CXCL12 in these BPMNs was increased gradually over coculturing time, and it may be a feasible marker for BPMNs. Furthermore, migration analysis results showed that the higher maturation of BPMNs collectively contributed to the creation of a more favorable niched site for the cancerous invasion. The subpopulation of breast cancer stem cells (BCSCs) was more likely to migrate to fertile BPMNs. The proportion of BCSCs in metastatic MDA-MB-231, MCF-7, and MDA-MB-453 cells were increased by approximately 63.47%, 149.48%, and 127.60%. The current study demonstrated that a designed tissue engineering scaffold can provide a novel method to create a bone-mimicking environment that serves as a useable platform to recapitulate the BPMNs and help interrogate the scheme of bone metastasis by breast cancer.

Detection and clinical significance of circulating tumor cells in colorectal cancer

Histopathological examination (biopsy) is the "gold standard" for the diagnosis of colorectal cancer (CRC). However, biopsy is an invasive method, and due to the temporal and spatial heterogeneity of the tumor, a single biopsy cannot reveal the comprehensive biological characteristics and dynamic changes of the tumor. Therefore, there is a need for new biomarkers to improve CRC diagnosis and to monitor and treat CRC patients. Numerous studies have shown that "liquid biopsy" is a promising minimally invasive method for early CRC detection. A liquid biopsy mainly samples circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), microRNA (miRNA) and extracellular vesicles (EVs). CTCs are malignant cells that are shed from the primary tumors and/or metastases into the peripheral circulation. CTCs carry information on both primary tumors and metastases that can reflect dynamic changes in tumors in a timely manner. As a promising biomarker, CTCs can be used for early disease detection, treatment response and disease progression evaluation, disease mechanism elucidation, and therapeutic target identification for drug development. This review will discuss currently available technologies for plasma CTC isolation and detection, their utility in the management of CRC patients and future research directions.

Morphological features of breast cancer circulating tumor cells in blood after physical and biological type of isolation

BACKGROUND

Circulating tumor cells (CTCs) have become an important biomarker in breast cancer. Different isolation tech-niques based on their biological or physical features were established. Currently, the most widely used methods for visualization after their separation are based on immunofluorescent staining, which does not provide the information on the morphology.

MATERIALS AND METHODS

The aim of this study was to evaluate how two different separation techniques affect cell morphology and to analyse cell morphology with techniques used in routine cytopathological laboratory. A direct side-by-side comparison of physical (Parsortix®) and biological (MACS®) separation technique was performed.

RESULTS

In the preclinical setting, both isolation techniques retained the viability and antigenic characteristics of MCF7 breast cancer cells. Some signs of degeneration such as cell swelling, cytoplasmic blebs, villous projections and vacuolization were observed. In metastatic breast cancer patient cohort, morphological features of isolated CTCs were dependent on the separation technique. After physical separation, CTCs with preserved cell morphology were detected. After biological separation the majority of the isolated CTCs were so degenerated that their identity was difficult to confirm.

CONCLUSIONS

Taken together, physical separation is a suitable technique for detection of CTCs with preserved cell morphology for the use in a routine cytopathological laboratory.

An Immune-Magnetophoretic Device for the Selective and Precise Enrichment of Circulating Tumor Cells from Whole Blood

Here, we validated the clinical utility of our previously developed microfluidic device, GenoCTC, which is based on bottom magnetophoresis, for the isolation of circulating tumor cells (CTCs) from patient whole blood. GenoCTC allowed 90% purity, 77% separation rate, and 80% recovery of circulating tumor cells at a 90 μL/min flow rate when tested on blood spiked with epithelial cell adhesion molecule (EpCAM)-positive Michigan Cancer Foundation-7 (MCF7) cells. Clinical studies were performed using blood samples from non-small cell lung cancer (NSCLC) patients. Varying numbers (2 to 114) of CTCs were found in each NSCLC patient, and serial assessment of CTCs showed that the CTC count correlated with the clinical progression of the disease. The applicability of GenoCTC to different cell surface biomarkers was also validated in a cholangiocarcinoma patient using anti-EPCAM, anti-vimentin, or anti-tyrosine protein kinase MET (c-MET) antibodies. After EPCAM-, vimentin-, or c-MET-positive cells were isolated, CTCs were identified and enumerated by immunocytochemistry using anti-cytokeratin 18 (CK18) and anti-CD45 antibodies. Furthermore, we checked the protein expression of PDL1 and c-MET in CTCs. A study in a cholangiocarcinoma patient showed that the number of CTCs varied depending on the biomarker used, indicating the importance of using multiple biomarkers for CTC isolation and enumeration.

Heterogeneity of Circulating Tumor Cells in Breast Cancer: Identifying Metastatic Seeds

Metastasis being the main cause of breast cancer (BC) mortality represents the complex and multistage process. The entrance of tumor cells into the blood vessels and the appearance of circulating tumor cells (CTCs) seeding and colonizing distant tissues and organs are one of the key stages in the metastatic cascade. Like the primary tumor, CTCs are extremely heterogeneous and presented by clusters and individual cells which consist of phenotypically and genetically distinct subpopulations. However, among this diversity, only a small number of CTCs is able to survive in the bloodstream and to form metastases. The identification of the metastasis-initiating CTCs is believed to be a critical issue in developing therapeutic strategies against metastatic disease. In this review, we summarize the available literature addressing morphological, phenotypic and genetic heterogeneity of CTCs and the molecular makeup of specific subpopulations associated with BC metastasis. Special attention is paid to the need for in vitro and in vivo studies to confirm the tumorigenic and metastatic potential of metastasis-associating CTCs. Finally, we consider treatment approaches that could be effective to eradicate metastatic CTCs and to prevent metastasis.