Clinical significance of phenotyping and karyotyping of detecting circulating tumor cells in renal cell carcinoma using subtraction enrichment and immunostaining-fluorescence in situ hybridization (SE-iFISH)

BACKGROUND AND OBJECTIVES

Circulating tumor cells (CTCs) as a noninvasive detection technology have become a research hotspot in the field of precision medicine. However, CTC detection faces great challenges with respect to specificity and sensitivity.

METHODS

We divided 39 subjects into three groups: renal carcinoma, renal stones and healthy persons. Using subtraction enrichment (SE) combined with immunostaining-fluorescence in situ hybridization technology, we identified and characterized CTCs. CTCs were identified as DAPI +/CD45-/PanCK + (-). We explored whether the number of CTCs was related to clinicopathological factors and their clinical application.

RESULTS

The CTC count in the renal carcinoma group (29/39) was 86.20% using a cut-off value of 1 CTC, which was significantly higher than that of other technologies in detecting CTCs, demonstrating that SE-iFISH technology can be used for CTC detection. The CTC count was much higher in the renal carcinoma group than that in the other control groups, with an area under the ROC curve of 0.931 (95% confidence interval 0.851 to 1.000, P < 0.01). In addition, the tetraploid count on chromosome 8 of T4 stage renal carcinoma was much higher than that of other stages (T1-T3), which may suggest that tetraploid count could be a marker of renal carcinoma prognosis and influence treatment decisions for better clinical management.

CONCLUSIONS

Our study showed that SE-iFISH technology can be used to detect CTCs in renal carcinoma with high sensitivity and specificity. Therefore, the analysis of CTCs with SE-iFISH has clear potential to improve the management of patients with renal carcinoma.

Circulating Tumor Cells: A Review of Non–EpCAM-Based Approaches for Cell Enrichment and Isolation

BACKGROUND

Circulating tumor cells (CTCs) are biomarkers for noninvasively measuring the evolution of tumor genotypes during treatment and disease progression. Recent technical progress has made it possible to detect and characterize CTCs at the single-cell level in blood.

CONTENT

Most current methods are based on epithelial cell adhesion molecule (EpCAM) detection, but numerous studies have demonstrated that EpCAM is not a universal marker for CTC detection because it fails to detect both carcinoma cells that undergo epithelial-mesenchymal transition (EMT) and CTCs of mesenchymal origin. Moreover, EpCAM expression has been found in patients with benign diseases. A large proportion of the current studies and reviews about CTCs describe EpCAM-based methods, but there is evidence that not all tumor cells can be detected using this marker. Here we describe the most recent EpCAM-independent methods for enriching, isolating, and characterizing CTCs on the basis of physical and biological characteristics and point out the main advantages and disadvantages of these methods.

SUMMARY

CTCs offer an opportunity to obtain key biological information required for the development of personalized medicine. However, there is no universal marker of these cells. To strengthen the clinical utility of CTCs, it is important to improve existing technologies and develop new, non–EpCAM-based systems to enrich and isolate CTCs.

Circulating glioma biomarkers

Validated biomarkers for patients suffering from gliomas are urgently needed for standardizing measurements of the effects of treatment in daily clinical practice and trials. Circulating body fluids offer easily accessible sources for such markers. This review highlights various categories of tumor-associated circulating biomarkers identified in blood and cerebrospinal fluid of glioma patients, including circulating tumor cells, exosomes, nucleic acids, proteins, and oncometabolites. The validation and potential clinical utility of these biomarkers is briefly discussed. Although many candidate circulating protein biomarkers were reported, none of these have reached the required validation to be introduced for clinical practice. Recent developments in tracing circulating tumor cells and their derivatives as exosomes and circulating nuclear acids may become more successful in providing useful biomarkers. It is to be expected that current technical developments will contribute to the finding and validation of circulating biomarkers.

[Circulating tumor cells: cornerstone of personalized medicine]

Cancer treatment has evolved toward personalized medicine. It is mandatory for clinicians to ascertain tumor biological features in order to optimize patients' treatment. Identification and characterization of circulating tumor cells demonstrated a prognostic value in many solid tumors. Here, we describe the main technologies for identification and characterization of circulating tumor cells and their clinical application in gynecologic and breast cancers.

[Quality control in pathology and theranostics in head and neck cancers]

Head and neck malignant tumors diagnosis require both standardized technical and personalized management in order to optimize patient care and therapy. The quality of multidisciplinary discussion for that goal needs common vocabulary. More than morphology, immunohistochemistry and in situ hybridization, additional molecular theranostics approaches are in fast progress in head and neck cancers, as well as their other anatomic counterparts.