Identification of Circulating Tumor Cell Phenotype in Differentiated Thyroid Carcinoma

Objective: Circulating tumor cells (CTCs) have been considered as the origin of tumor metastasis and recurrence, which always indicate a poor prognosis. There are three phenotypes of CTCs according on different epithelial-to-mesenchymal transition (EMT) markers, including epithelial, mesenchymal, and epithelial/mesenchymal (mixed phenotypic) CTCs. We intended to explore the relationship among CTC phenotypes and the clinicopathological characteristics of patients with differentiated thyroid carcinoma (DTC). Methods: Peripheral blood samples from 58 patients with DTC were collected, and CTCs were isolated by cell sizes. To identify phenotypes of CTCs, branched DNA signal amplification technology was adopted to capture and amplify target sequences, and then multiplex RNA-in situ hybridization (RNA-ISH) assay was used to identify CTC phenotypes depended on epithelial-mesenchymal transition (EMT) markers. Results: The positive rate of CTCs was 77.59% in 58 DTC patients. Totally, 488 CTCs with detective phenotype were found. Among them, there were 121 (24.80%) epithelial CTCs, 67 (13.72%) mesenchymal CTCs, and 300 (61.48%) mixed phenotypic CTCs. An obvious increased epithelial CTCs was observed in male patients compared with female. Notably, CTCs were more prevailing in younger male patients with ETI and bilateral focus. Conclusions: The CTCs are common in DTC patients, and mixed phenotypic is the major phenotype, indicating that EMT is prevalent in DTC even though its prognosis was better than other epithelial tumors. Detection of CTC and its phenotypes might independently predict the prognosis of DTC.

Blood indices and circulating tumor cells for predicting metastasis of hepatocellular carcinoma after liver transplantation

Objectives Liver transplantation (LT) can benefit the long-term survival of hepatocellular carcinoma (HCC) patients. We hypothesized that circulating tumor cell (CTC) levels and subtypes are intimately associated with metastasis status of HCC patients. This study was designed to test that compositive hematological indices including CTC can provide a prediction of post-LT metastasis. Methods Between 2017 and 2018, 37 HCC patients within Hangzhou criteria receiving LT were included for analysis. The 24-month follow-up was mainly conducted by outpatient and telephone. Blood samples were collected, and hematological indices were examined. The outcomes such as PFS, recurrence, metastasis, location of recurrence/metastasis, and number of metastases were recorded. Results The follow-up analysis showed that microvascular invasion (MVI) classification at the baseline is associated with metastasis. Next, α-fetoprotein (AFP) level was another useful indicator of postoperative metastasis, especially at the third or fourth month; the protein induced by vitamin K absence or antagonist-II (PIVKA-II) level three months after LT was significantly higher for those who had later metastasis. The mesenchymal CTC level at the 45th day was increased for in the metastasis group. Using two-ends Logistic regression, the calculated value MP (metastasis predictor, by above factors). Had an AUC of 0.858 in the ROC curve, with a cutoff value of 0.328. Conclusions In conclusion, microvascular invasion, AFP level at the third or fourth month, PIVKA-II level at the third month, and mesenchymal CTC level at day 45 were associated with post-LT metastasis. Using Logistic regression based on above variables, the two-year metastasis can be predicted with satisfactory sensitivity and accuracy.

Specific alternative splicing and polyadenylation facilitate metastasis mediated by CTC clusters

Circulating tumor cell (CTC) clusters possess a much higher capability to seed metastasis than single CTCs. However, the mechanism underlying this phenomenon is still elusive and no reports have investigated the role of posttranscriptional RNA regulation in CTC clusters. Here, we compared alternative splicing (AS) and alternative polyadenylation (APA) profiles between single CTCs and CTC clusters. 994 and 836 AS events were identified in single CTCs and CTC clusters, separately. About ~20% of AS events exhibited alterations between both cell types. The differential splicing of SRSF6 was a core event that caused AS profiles’ disturbance and made CTC clusters more dangerous. Concerning APA, we identified global 3’ UTRs lengthening in CTC clusters compared with single CTCs. This change was mainly regulated by 14 core APA factors, especially PPP1CA. The altered APA profiles boosted the cell cycle of CTC clusters and reflected that CTC clusters endured less oxidative stress. Our study investigated the posttranscriptional regulation mechanisms in CTC clusters, found that the perturbation of AS and APA contributed to the superiority of CTC clusters compared with single CTCs, and laid the foundation for developing antisense oligonucleotides that inhibit metastasis by reducing CTC clusters.

Circulating Tumor Cells Enumeration from the Portal Vein for Risk Stratification in Early Pancreatic Cancer Patients

Background. Effective biomarkers are needed to enable personalized medicine for pancreatic cancer patients. This study analyzes the prognostic value, in early pancreatic cancer, of single circulating tumor cell (CTC) and CTC clusters from the central venous catheter (CVC) and portal blood (PV). Methods. In total, 7 mL of PV and CVC blood from 35 patients with early pancreatic cancer were analyzed. CTC were isolated using a positive immunomagnetic selection. The detection and identification of CTC were performed by immunocytochemistry (ICC) and were analyzed by Epi-fluorescence and confocal microscopy. Results. CTC and the clusters were detected both in PV and CVC. In both samples, the CTC number per cluster was higher in patients with grade three or poorly differentiated tumors (G3) than in patients with well (G1) or moderately (G2) differentiated. Patients with fewer than 185 CTC in PV exhibited a longer OS than patients with more than 185 CTC (24.5 vs. 10.0 months; p = 0.018). Similarly, patients with fewer than 15 clusters in PV showed a longer OS than patients with more than 15 clusters (19 vs. 10 months; p = 0.004). These significant correlations were not observed in CVC analyses. Conclusions. CTC presence in PV could be an important prognostic factor to predict poor prognosis in early pancreatic cancer. In addition, the number of clustered-CTC correlate to a tumor negative differentiation degree and, therefore, could be used as a diagnostic biomarker for pancreatic cancer.