Total Circulating Tumor Cells Research Articles

Plastin 3 Expression in Circulating Tumor Cells as a Predictor of Cancer Status in Patients with Prostate Cancer

Abstract Objectives To identify the role of plastin3 (PLS3) expression in circulating tumor cells (CTCs) of early stage prostate cancer (PCa). Materials and Methods CTCs were collected from 23 prostate cancer patients based on cell surface markers targeting prostate cancer by V-BioChip. Condition of Plastin3 expression and correlations to the prostate cancer were also analyzed. Results Of the 23 patients with prostate cancer, total CTCs (CK+ or PLS3+) were found in 11 patients and PLS3+ CTCs were detected in 10 patients. When the cohort was stratified by risk group, 90% of the high-risk patients were found to have PLS3+ circulating tumor cells (9/10 patients). However, only 15.4% of low/intermediate-risk patients had PLS3+ circulating tumor cells (2/13 patients). The number of PLS3+ CTCs was higher in the high-risk group. Conclusions The expression of PLS3 in CTCs is associated with prostate cancer risk. Further study of PLS3+ CTCs for prognosis prediction is required for clinical application in prostate cancer patients.

Abstract PO2-15-04: Fas/FasL expression on circulating tumor and immune cells in the peripheral blood of patients with metastatic breast cancer (BC): correlation with clinical outcome

Abstract Background: The activation of Fas (CD95/APO-1) death receptor by Fas ligand (FasL/CD95L) can trigger a signal transduction pathway leading to apoptosis, which is a common pathway used by immune cells for tumor elimination. Cancer cells also exploit FasL expression to induce immune cell apoptosis, known as "Fas counterattack", and thus to increase their invasion and migration capacity. We herein assessed the expression of Fas and FasL on circulating tumor cells (CTCs) and immune cells in the peripheral blood (PB) of patients with metastatic BC. Methods: PB was obtained from 98 patients with metastatic BC at baseline before first-line treatment. Peripheral blood mononuclear cells (PBMCs) were isolated and immunofluorescently stained with antibodies against cytokeratins (CK; clones: AE1/AE3 & C11) and CD45 for CTC detection, along with antibodies for Fas, FasL and dapi. Fas/FasL expression was individually assessed on CTCs and PBMCs using the Ariol microscopy system (2x10^6 PBMCs were analyzed per patient). Results: CTCs were detected in 26/98 (26.5%) patients (total CTC count: n=70). Fas+ CTCs and FasL+ CTCs were identified in 88.5% and 92.3% of CTC-positive patients, respectively, representing the 57.1% and 82.9% of total CTCs. Regarding co-expression at single cell level, Fas+/FasL+ CTCs were detected in 84.6% of patients, whereas Fas+/FasL- CTCs, Fas-/FasL+ CTCs and Fas-/FasL- CTCs were identified in 7.7%, 19.2% and 11.5% of patients, respectively. Regarding PBMCs, the Fas+/FasL+ phenotype was identified in 70.3%, of patients, whereas Fas-/FasL+ PBMCs and Fas-/FasL- PBMCs were detected in 24.2% and 5.5% of patients, respectively; interestingly the Fas+/FasL- expression pattern was not observed in any patient. A reduced progression-free survival (PFS) was demonstrated among CTC-positive as compared to CTC-negative patients (median PFS: 9.5 versus 13.4 months; p=0.004), and specifically those harboring Fas+/FasL+ CTCs (median PFS: 9.5 vs 13.4 months; p=0.009). Increased overall survival (OS) was demonstrated among patients harboring Fas+/FasL+ PBMCs, as compared to those with Fas-/FasL+ PBMCs and Fas-/FasL- PBMCs (median OS: 35.7 vs 25.9 vs 14.4 months; p=0.008). Conclusion: Herein we provide for the first time evidence on Fas/FasL expression on CTCs and PBMCs with significant prognostic relevance for patients with metastatic BC. The findings highlight the Fas/FasL signaling pathway as a putative mechanism of immune evasion and metastatic progression of BC. Their role as prognostic biomarkers in BC patients merits further investigation. Citation Format: Maria Papadaki, Maria Vassilakopoulou, Eleni Papadaki, Despoina Aggouraki, Chrysostomos Zioudas, Anastasia Mala, Sofia Agelaki, Dimitrios Mavroudis. Fas/FasL expression on circulating tumor and immune cells in the peripheral blood of patients with metastatic breast cancer (BC): correlation with clinical outcome [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-15-04.

The correlation study between TOP2A gene expression in circulating tumor cells and chemotherapeutic drug resistance of patients with breast cancer

BackgroundPatients with breast cancer (BC) at advanced stages have poor outcomes because of high rate of recurrence and metastasis. Biomarkers for predicting prognosis remain to be explored. This study aimed to evaluate the relationships between circulating tumor cells (CTCs) and outcomes of BC patients.Patients and methodsA total of 50 female were enrolled in this study. Their diagnoses were determined by clinical characteristics, image data, and clinical pathology. CTC subtypes and TOP2A gene expression on CTCs were detected by CanPatrol™ technology and triple color in situ RNA hybridization (RNA-ISH), which divided into epithelial CTCs (eCTCs), mesenchymal CTCs (MCTCs), and hybrid CTCs (HCTCs) based on their surface markers. Hormone receptor, including estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2) expression, was measured by immunohistochemistry (IHC) method before treatment. The risk factors for predicting recurrence and metastasis were calculated by COX risk regression model. The progression-free survival (PFS) of patients was determined using Kaplan–Meier survival curve.ResultsThe patients with a large tumor size (≥ 3 cm) and advanced tumor node metastasis (TNM) stages had high total CTCs (TCTCs) (P < 0.05). These patients also had high TOP2A expression level. COX risk regression analysis indicated that TOP2A expression levels in TCTCs, ER + , HER-2 + , and TNM stages were critical risk factors for recurrence and metastasis of patients (P < 0.05). The PFS of patients with ≥ 5 TCTCs, ≥ 3 HCTCs, and positive TOP2A expression in ≥ 3 TCTCs was significantly longer than that in patient with < 5 TCTCs, < 3 HCTCs, and TOP2A expression in < 3 TCTCs (P < 0.05). In contrast, the PFS of patients with positive hormone receptors (ER + , PR + , HER-2 +) also was dramatically lived longer than that in patients with negative hormone receptor expression.ConclusionsHigh TCTC, HCTCs, and positive TOP2A gene expression on CTCs were critical biomarkers for predicting outcomes of BC patients. Positive hormone receptor expression in BC patients has significant favor PFS.

Detection of γ-OHPdG in Circulating Tumor Cells of Patients With Hepatocellular Carcinoma as a Potential Prognostic Biomarker of Recurrence

Background and AimsBlood-based biomarkers for hepatocellular carcinoma (HCC) and its recurrence is lacking. We previously showed that hepatic γ-hydroxy-1,N2-propano-2′-deoxyguanosine (γ-OHPdG), an endogenous DNA adduct derived from acrolein by lipid peroxidation, increased during hepatocarcinogenesis. Additionally, higher hepatic γ-OHPdG from HCC patients after surgery were strongly associated with poor survival (P < .0001) and recurrence-free survival (P = .007) (Fu Y et al., Hepatology, 2018). These findings suggest that γ-OHPdG is a potential prognostic biomarker for HCC and its recurrence. To attain the goal of using γ-OHPdG as a biomarker in future preventive and therapeutic trials, we developed a blood-based method to detect γ-OHPdG in circulating liver tumor cells from HCC patient blood. MethodsWe first established the specificity of anti-γ-OHPdG antibody by determining its dose-response in HepG2 cells treated with acrolein. Then, HepG2 cells in spiked blood of healthy volunteers (HV) and circulating tumor cells (CTCs) from 32 HCC patients were isolated using a RosetteSep™ CD45 Depletion Cocktail and Ficoll Paque. The HCC CTCs identified with anti-asialoglycoprotein receptor 1, a surface protein expressed solely in hepatocytes, were stained with an anti-γ-OHPdG antibody. The number of total HCC CTCs and γ-OHPdG-positive CTCs, as well as the staining intensity, were quantified using a MetaMorph software. As an initial effort toward its clinical application, we also evaluated γ-OHPdG in CTCs from these patients along with certain clinical features. ResultsThe γ-OHPdG antibody specificity was demonstrated by an acrolein concentration-dependent increase of γ-OHPdG-positive HepG2 cells and the intensity of γ-OHPdG staining. The recovery of HepG2 cells from spiked blood was ∼50-60%, and the positivity rate of CTCs in blood from 32 patients with advanced HCC was 97%. The MetaMorph analysis showed a wide variation among patients in total number of CTCs, γ-OHPdG positivity, and staining intensity. Statistical analysis revealed γ-OHPdG in CTCs of these patients appear to be associated with multifocality and poor differentiation. ConclusionsA blood-based method was developed and applied to HCC patients to evaluate the potential of γ-OHPdG in CTCs as a prognostic biomarker.

Abstract 7665: Detection of γ-OHPdG as a hepatocellular carcinoma recurrence biomarker by CTCs and LC-MS/MS

Abstract Background: Hepatocellular carcinoma (HCC) is the third leading cause of cancer death globally. Recurrence risks following curative resection remain high, ~50% after three years and 75-100% over five years. A biomarker for HCC recurrence is urgently needed to help lead treatment strategies. We previously showed that hepatic γ-hydroxy-1, N2-propano-2′-deoxyguanosine (γ-OHPdG), a DNA adduct derived from lipid peroxidation, increased during hepatocarcinogenesis. Furthermore, in a retrospective study, higher γ-OHPdG levels in post-surgical liver tumor tissues were associated with poorer survival (p&amp;lt;0.0001) and shorter recurrence-free survival (p=0.007), suggesting that it may be a prognostic biomarker for HCC (Hepatology 2018). In this study, we aimed to test γ-OHPdG detected in livers after curative resection as a recurrence biomarker in a prospective study and, in addition, we developed a new non-invasive method for γ-OHPdG in circulating tumor cells (CTCs). This multicenter study seeks to validate γ-OHPdG as a biomarker for HCC recurrence. Methods: A total of 28 HCC patients undergoing hepatectomy at MedStar/Georgetown University Hospital, Johns Hopkins University Hospital, and the University of Maryland Medical Center were enrolled. γ-OHPdG was detected in DNA isolated from hepatic tumors and non-tumors by a previous liquid chromatograph-tandem mass spectrometry (LC-MS/MS) method and in HCC CTCs isolated from blood samples. CTCs were isolated using hepatocyte-specific rabbit anti-asialoglycoprotein-1 (ASGPR-1), followed by staining with mouse anti-γ-OHPdG antibodies. Clinical outcomes were correlated with γ-OHPdG in liver tissues and CTCs. Results: In our current cohort of 28 patients (mean age: 64.7 years; 82% male), five patients experienced HCC recurrence, with an estimated progression-free survival (PFS) rate of 85% over 8 months. γ-OHPdG levels (adducts/109 nucleotides) detected by LC-MS/MS varied widely in tumor tissues (5-56, mean: 11.8) and non-tumor tissue (7-71, mean: 20.6). Preliminary analysis showed shorter PFS associated with γ-OHPdG in non-tumors (cutoff: 16, p=0.0271). γ-OHPdG (arbitrary units x107) in CTCs also varied widely in the nucleus (0.95-18.84, mean: 2.85) and in the whole cell (0.16- 52.18, mean: 9.72). Total CTC γ-OHPdG intensity in both the nucleus (p=0.006) and in the whole cell (p=0.005) was associated with its levels in non-tumor tissue. Furthermore, a shorter PFS was associated with CTC count (cutoff: 270 cells, p=0.01), and total CTC whole cell γ-OHPdG intensity (cutoff: 21.17 × 107 arbitrary units, p=0.002). Conclusion: Preliminary results suggest that γ-OHPdG, measured in tissues by LC-MS/MS and in blood by CTC, predicts HCC recurrence. Once evaluated in all enrolled subjects, multiple variant analyses will be carried out to include stage, AFP, grade of differentiation, vascular invasion on surgical samples, and status of viral hepatitis infection. Citation Format: Mark Kuo, Merve Ozge Aktop, Elie Ghabi, Mahmoud A. Ouf, Margaret Carder, Vinona Muralidaran, Jhalen Ascue, Marketa Hlouskova, Pengfei Wu, Guang Cheng, Stephen S. Hecht, Hong-Bin Fang, Nader Hanna, Jin He, Alexander H. Kroemer, Monika Aggarwal, Aiwu R. He, Fung-Lung Chung. Detection of γ-OHPdG as a hepatocellular carcinoma recurrence biomarker by CTCs and LC-MS/MS [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7665.

Abstract 7495: Validation of microfluidic isolation of circulating pancreatic tumor cells from blood

Abstract Background. Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis and is the fourth leading cause of cancer-related deaths in the US. PDAC is diagnosed in the late stages, which limits treatment options and yields poor clinical outcomes. Recurrence is a significant issue for patients undergoing surgery for PDAC. Circulating tumor cells (CTCs) are thought to be a potential mediator of recurrence, facilitating the formation of secondary tumor sites after surgery. Thus, there is a need to isolate CTCs to improve understanding of disease recurrence, to ultimately improve outcomes. Herein, we aim to validate our inertial microfluidic (iMF) system for isolating pancreatic CTCs from blood. We also benchmark our iMF system to a commercially available immunomagnetic negative selection system, EasySep™, and quantify target cell recovery and cell enrichment. Methods. Our iMF system employs the differential cell sizes of CTCs from blood cells and inertial migration of such cells in a straight microchannel (150 µm × 50 µm × 24 mm) to enrich CTCs from blood. The iMF system sample flow rate used is 100 µL/min, with a 200 µL/min PBS buffer flow rate. The EasySep™ Direct Human CTC Enrichment kit targets CD2, CD14, CD16, CD19, CD45, CD61, CD66b, and Glycophorin to remove blood cells from the sample using magnetic particles, thereby separating them from CTCs. We spiked low cell concentrations of 50, 100, and 500 Hoechst-stained pancreatic carcinoma cells, PANC1, in 1 mL of healthy blood then captured using either EasySep™ or iMF. Cell enumeration was performed after centrifugation or Cytospin. Results. PANC1 cells and WBCs have average sizes of 18 µm and 8.4 µm, respectively. We characterized our iMF device to capture cells ≥ 12 µm, which yields capture of most PANC1 cells. Indeed, our iMF system achieved 82.8±19.2%, 72.5±16.3%, and 59.3±3.8% recovery for 50, 100, and 500 cell-spikes in lysed blood, respectively. For the same 50, 100, and 500 cell-spikes, the total iMF CTC yields after Cytospin were 46.3±11.8, 44.3±9.1, and 32.7±2.1%, while the total CTC yields from EasySep™ were 4.6±3, 5.3±2.1, 8.3±1%, respectively. When we processed whole blood directly, EasySep™ had lower cell recovery, 3.8±0.2, 4.6±1, and 3.3±0.4%, respectively. Our system also demonstrated 8 × higher target cell enrichment compared to EasySep™. Blood lysis before iMF separation did not drastically affect the recovery of target cells. Conclusions. We determined that our system has improved performance over the commercial isolation system, EasySep™, thereby validating the effectiveness of microfluidic isolation for PDAC. In future studies, we can then use our iMF system in CTC isolation from routine blood draws from PDAC patients undergoing surgical resection. We may then isolate real patient samples and study relevant phenotypes of PDAC CTCs which may therefore be used for identifying certain mechanisms of PDAC progression. Citation Format: Celine Macaraniag, Ifra Khan, Jian Zhou, Pier Cristoforo Giulianotti, Alain Borgeat, Gina Votta-Velis, Ian Papautsky. Validation of microfluidic isolation of circulating pancreatic tumor cells from blood [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7495.

Abstract 3702: Dissecting circulating tumor cells phenotype in a cohort of locally advanced non-small cell lung cancer patients undergoing neoadjuvant chemotherapy

Abstract Background: Platinum-based neoadjuvant chemotherapy (pb-NACT) is the primary treatment approach for locally advanced non-small cell lung cancer (LA-NSCLC), despite offering only a limited overall survival (OS) gain. Cisplatin-induced cell damage has been shown to activate the SDF-1/CXCR4 axis in preclinical models of NSCLC, resulting in the recruitment of a cell subset co-expressing the stemness marker CD133 and CXCR4 (SDF-1 receptor) at distant sites. These cells, known as metastasis-initiating cells (MIC), exhibit prometastatic activity. By longitudinally monitoring circulating tumor cells (CTC) in the blood of LA-NSCLC patients (pts) undergoing pb-NACT, our objective is to assess the potential prognostic significance of CTC number and phenotype. Methods: Between February 2019 and August 2023, a total of 61 pts with LA-NSCLC undergoing pb-NACT, were included in the study. Blood samples were obtained at baseline (T1), post-pb-NACT (T2), and post-surgery (T3) for the characterization of CTC, including total CTC, CXCR4+CTCs, and CXCR4+CD133+ MIC. This characterization utilized a validated marker-independent strategy combining Parsortix and DEPArrayTM technologies. Logistic regression models were employed to examine the association between CTC subsets and the response to pb-NACT (Disease Control Rate [DCR], Overall Response Rate [ORR]), while Cox-regression models were used to assess their association with survival endpoints (event-free survival [EFS], OS, disease-free survival [DFS]). Results: Out of the 61 enrolled patients, 34 had available CTC data for analysis. In this population, DCR was 64.7%, and the ORR 29.4%. Surgery was performed in 14 pts (41.2%). At baseline (T1), elevated levels of CXCR4+CTCs were linked to a lower DCR (10 vs 3/mL, odds ratio [OR]=0.02, 95% confidence interval [CI]: 0-0.40, p=0.008), as well as shorter EFS (10 vs 3/mL, HR=4.20, 95% CI: 1.84-9.58, p=0.002) and OS (10 vs 3/mL, HR=3.14, 95% CI: 1.25-7.88, p=0.004). At the post- CT time point (T2), higher levels of MIC were associated with shorter EFS (3 vs 0/mL, HR=1.41, 95% CI: 1.00-1.99, p=0.047) and OS (3 vs 0/mL, HR=1.55, 95% CI: 1.03-2.34, p=0.035). Although the sample size was limited, a higher number of MIC at the post-surgery time point (T3) showed a trend toward reduced DFS. Discussion: CTC could serve as a novel biomarker for assessing the effectiveness of pb-NACT in LA-NSCLC. Elevated levels of CXCR4+CTC both at baseline and after pb-NACT, along with increased MIC post-pb-NACT and post-surgery, indicate unfavorable prognostic factors for survival. Specifically, a higher baseline of CXCR4+CTCs may be linked to a suboptimal response to treatment, suggesting the potential need for treatment intensification in patients exhibiting elevated CXCR4+CTC baseline levels. Citation Format: Rita Leporati, Teresa Beninato, Sara Iadecola, Chiara Andreon, Fabio Murianni, Melissa Balsamo, Antonia Martinetti, Benedetta Lombardi Stocchetti, Laura Mazzeo, Sara Manglaviti, Mario Occhipinti, Marta Brambilla, Arsela Prelaj, Claudia Proto, Rosalba Miceli, Luca Roz, Gabriella Sozzi, Filippo De Braud, Giuseppe Lo Russo, Giulia Bertolini. Dissecting circulating tumor cells phenotype in a cohort of locally advanced non-small cell lung cancer patients undergoing neoadjuvant chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3702.

Abstract 3693: Molecular and functional characterization of circulating CK+/CD45+ cells in breast cancer

Abstract Background: Circulating tumor cells (CTCs) are considered a key element in metastatic progression and represent a validated prognostic biomarker in breast cancer (BC). CTCs in BC are normally defined as epithelial cells (positive for EPCAM or cytokeratin, CK) lacking the expression of the leukocyte marker CD45. Circulating cells expressing both EPCAM/CK and CD45 (dual positive, DPcells) have however been reported in BC but not investigated. It is believed that DPcells derive from the heterotypic cell fusion of tumor and immune cells, but this hypothesis has not been demonstrated yet. We recently reported, for the first time, the association of DPcells with worse survival in a cohort of 341 BC patients (pts) [Reduzzi et al. ASCO 2022] supporting their tumor origin. Here, we further investigated their malignancy and metastatic potential by molecular profiling and functional experiments. Methods: The study consisted of 2 components: A) Single CTCs and DPcells were enriched from the blood of BC patients with the CellSearch platform, and isolated with the DEPArray system. Single cells underwent whole genome amplification and lowpass whole genome sequencing for single cell copy number alteration (CNA) profiling; B) DPcells and CTCs were investigated in the blood of immunodeficient (NSG) and immunocompetent (FVB) mouse models using various cell lines (LM2, 4T1, MVT1). To test their metastatic potential, DPcells from the primary tumor of FVB donor mice were transplanted into recipient NSG mice, and the metastatic burden in the lungs and liver quantified, in comparison with control CD45- tumor cells. Results: We analyzed 73 DPcells and 18 CTCs collected from 16 BC pts: Aberrant genomes were observed in 28% and 93% of evaluable cells, respectively. When collected from the same pt, CTCs showed clonal CNA profiles, while DPcells were highly heterogeneous. In vivo, DPcells could only be detected in the blood of FVB mice but not in NSG mice. They were very rare, comprising of only about 3% of the total CTC count. When DPcells and control tumor cells were isolated from the primary tumor of 10 donor mice and transplanted into the tail vein of 10 recipient mice, we observed no significant differences in the metastatic colonization of the lungs and liver by the two population, indicating that DPcells do in fact possess metastatic ability, and to a similar extent as control cancer cells. Conclusions: DPcells can have an aberrant genome, supporting their malignancy. Contrary to CTCs, DPcells’ CNA profiles are not clonal and, in vivo, they can only be observed in immunocompetent models; both observations support the tumor/immune fusion hypothesis. Finally, DPcells show metastatic potential in mice, in line with the association with worse survival we previously observed in BC pts. Overall DPcells seem a new CTC subpopulation that should not be neglected anymore. More studies are needed to better understand their origin and phenotypic/molecular features. Citation Format: Carolina Reduzzi, Eleonora Nicolo, Lauren L. Ozimski, Marco Silvestri, Lorenzo Gerratana, Mara S. Serafini, Elisabetta Molteni, Nadia Bayou, Amanda K. Strickland, Huiping Liu, Vera Cappelletti, Nicola Aceto, Massimo Cristofanilli. Molecular and functional characterization of circulating CK+/CD45+ cells in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3693.

Prognostic evaluation of a multi-target magnetic bead-enriched circulating tumor cell-enriched identification system for colorectal cancer.

Colorectal cancer (CRC) is the third most prevalent cancer in the world. Traditional tissue biopsy cannot provide dynamic monitoring of patients' tumors or reflect the characteristics of tumors in real time because the sampling process is invasive and accompanied by risks. Circulating tumor cells (CTCs) are considered a major cause of tumor metastasis, and investigating CTCs helps to understand the biology and vulnerability of malignant tumors during hematogenous metastasis. We sequentially used epithelial cell adhesion molecule (EpCAM)-coated immunoliposomal magnetic beads (Ep-IMBs) and vimentin-coated immunoliposomal magnetic beads (Vi-IMBs) to capture and characterize CTCs from 110 CRC patients. We further constructed a Cox risk regression model, optimized the model composition using backward stepwise regression, and finally applied nomograms to show the effect of each variable on survival risk. The specificity of the CTCs enrichment and identification system was 100% and the sensitivity was 79.0%. Multivariate analysis indicated total CTC number was an important predictor for bad survival, whereas American Joint Committee on Cancer (AJCC) stage, lymph node metastasis, and carcinoembryonic antigen (CEA) level were associated with prognosis, and the risk of mortality was associated with the AJCC stage of the CRC. The CTC enrichment and identification system constructed in this research demonstrated superior accuracy. In addition, CTCs can be used as an important predictor for prognosis of patients with CRC, and the combination of other clinical predictive factors can help clinicians to better design individualized treatment regimens, which is of great clinical application value.

Effect of various hepatectomy procedures on circulating tumor cells in postoperative patients: a case-matched comparative study.

The objective of this study is to elucidate the prevalence of systemic circulating tumor cells (CTCs) prior to and following resection of hepatocellular carcinoma (HCC), and to compare the disparities in postoperative CTCs in terms of quantity and classifications between the open liver resection (OPEN) and laparoscopic liver resection (LAP) cohorts. From September 2015 to May 2022, 32 consecutive HCC patients who underwent laparoscopic liver resection at Southwest Hospital were retrospectively enrolled in this study. The clinicopathological data were retrieved from a prospectively collected computer database. Patients in the OPEN group matched at a 1:1 ratio with patients who underwent open liver resection during the study period on age, gender, tumor size, number of tumors, tumor location, hepatitis B surface antigen (HBsAg) positivity, alpha-fetoprotein (AFP) level, TNM and Child-Pugh staging from the database of patients to form the control group. The Can-Patrol CTC enrichment technique was used to enrich and classify CTCS based on epithelial-mesenchymal transformation phenotypes. The endpoint was disease-free survival (DFS), and the Kaplan-Meier method and multiple Cox proportional risk model were used to analyze the influence of clinicopathological factors such as total CTCs and CTC phenotype on prognosis. The mean age of the 64 patients with primary liver cancer was 52.92 years (23-71), and 89.1% were male. The postoperative CTC clearance rate was more significant in the OPEN group. The total residual CTC and phenotypic CTC of the LAP group were significantly higher than those of the OPEN group (p = 0.017, 0.012, 0.049, and 0.030, respectively), which may increase the possibility of metastasis (p = 0.042). In Kaplan-Meier analysis, DFS was associated with several clinicopathological risk factors, including Barcelona Clinical Liver Cancer (BCLC) stage, tumor size, and vascular invasion. Of these analyses, BCLC Stage [p = 0.043, HR (95% CI) =2.03(1.022-4.034)], AFP [p = 0.007, HR (95% CI) =1.947 (1.238-3.062)], the number of positive CTCs [p = 0.004, HR (95% CI) =9.607 (2.085-44.269)] and vascular invasion [p = 0.046, HR (95% CI) =0.475 (0.22-1.023)] were significantly associated with DFS. In comparison to conventional OPEN technology, LAP technology has the capacity to augment the quantity of epithelial, mixed, and mesenchymal circulating tumor cells (CTCs). Following the surgical procedure, there was a notable increase in the total CTCs, epithelial CTCs, and mixed CTCs within the LAP group, indicating a potential drawback of LAP in facilitating the release of CTCs.

Phenotypic characteristics of circulating tumor cells and predictive impact for efficacy of chemotherapy in patients with pancreatic cancer: a prospective study.

Early chemoresistance and tumor mass progression are associated with poor prognosis in pancreatic ductal adenocarcinoma (PDAC). Circulating tumor cells (CTCs) have been studied as potential predictors of treatment response and prognosis in PDAC; however, this approach has yet to be applied in clinical practice. The aim of our study was to investigate the phenotypic characteristics of CTCs and determine their predictive value for PDAC progression. We prospectively enrolled 40 patients who were pathologically diagnosed with PDAC and collected blood samples at diagnosis, 2 months after diagnosis, and during disease progression or recurrence. We used a microfabricated filter-based enrichment system to retrieve and analyze CTCs, which were classified using immunofluorescence staining (CD45, EpCAM, and vimentin). Our study included 20 women and 20 men (median age, 66 years). Overall, 45% of the patients (18/40) had disseminated disease, and 77.5% (31/40) received chemotherapy. Multivariate analysis revealed that the total CTC count and carbohydrate antigen 19-9 level at 2 months after diagnosis were associated with disease progression (P<0.05). Linear mixed model analysis revealed that the total CTC count and vimentin-positive CTCs were significantly correlated with treatment response during chemotherapy (P=0.024 and 0.017, respectively). Kaplan-Meier analysis showed that total CTC positivity at 2 months was significantly associated with poor progression-free survival (P=0.038). Our study's findings suggest that CTCs can serve as predictive biomarkers of clinical outcomes in patients with PDAC receiving palliative chemotherapy. In particular, the total CTC count and vimentin-positive CTCs showed changes associated with the chemotherapy response.

Nomograms for postsurgical extrahepatic recurrence prediction of hepatocellular carcinoma based on presurgical circulating tumor cell status and clinicopathological factors.

Extrahepatic recurrence (EHR) is one of the major reasons for the poor prognosis of hepatocellular carcinoma (HCC). The present study aimed to develop and assess the performance of predictive models by using a combination of presurgical circulating tumor cell (CTCs) data and clinicopathological features to screen patients at high risk of EHR to achieve precise decision-making. A total of 227 patients with recurrent HCC and preoperative CTC data from January 2014 to August 2019 were enrolled. All patients were randomly assigned to one of two cohorts: development or validation. Two preoperative and postoperative nomogram models for EHR prediction were developed and multi-dimensionally validated. Patients with EHR had generally lower recurrence-free survival (p < 0.001), and overall survival (p < 0.001), and significantly higher CTC counts (epithelial CTCs, epithelial/mesenchymal hybrid CTCs, and mesenchymal CTCs count, all p < 0.05) than those without EHR. Univariate and multivariate analyses revealed that EHR was associated with four risk factors in the development cohort: total CTC count (p = 0.014), tumor size (p = 0.028), node number (p = 0.045), and microvascular invasion (p = 0.035). These factors were incorporated into two nomogram models (preoperative and postoperative), which reliably predicted EHR through multidimensional verification (e.g., calibration plot, receiver operating characteristic analysis, decision curve analysis, and clinical impact curve analysis) in the development and validation cohorts, respectively. With threshold of scores of 100.3 and 176.8 before and after surgery respectively, both nomograms were able to stratify patients into two distinct prognostic subgroups (all p < 0.05). The present study proposed two nomogram models integrating presurgical CTC counts and clinicopathological risks and showed relatively good predictive performance of EHR, which may be beneficial to the clinical practice of HCC recurrence. Further multicenter studies are needed to assess its general applicability.

Heterogeneous circulating tumor cells correlate with responses to neoadjuvant chemotherapy and prognosis in patients with locally advanced breast cancer.

Neoadjuvant chemotherapy (NCT) is the standard treatment for patients with locally advanced breast cancer (LABC). The predictive value of heterogeneous circulating tumor cells (CTCs) in NCT response has not been determined. All patients were staged as LABC, and blood samples were collected at the time of biopsy, and after the first and eighth NCT courses. Patients were divided into High responders (High-R) and Low responders (Low-R) according to Miller-Payne system and changes in Ki-67 levels after NCT treatment. A novel SE-i·FISH strategy was applied to detect CTCs. Heterogeneities were successfully analyzed in patients undergoing NCT. Total CTCs increased continuously and were higher in Low-R group, while in High-R group, CTCs increased slightly during NCT before returning to baseline levels. Triploid and tetraploid chromosome 8 increased in Low-R but not High-R group. The number of small CTCs in Low-R group increased significantly until the last sample, however, remained constant in High-R group. The patients with more CTCs had shorter PFS and OS than those with less CTCs after the eighth course of NCT. Total CTCs following NCT could predict patients' responses. More detailed characterizations of CTC blood profiles may improve predictive capacity and treatments of LABC.

Circulating tumor cells (CTCs) and hTERT gene expression in CTCs for radiotherapy effect with lung cancer

BackgroundCirculating tumor cells (CTCs) are important biological indicators of the lung cancer prognosis, and CTC counting and typing may provide helpful biological information for the diagnosis and treatment of lung cancer.MethodsThe CTC count in blood before and after radiotherapy was detected by the CanPatrol™ CTC analysis system, and the CTC subtypes and the expression of hTERT before and after radiotherapy were detected by multiple in situ hybridization. The CTC count was calculated as the number of cells per 5 mL of blood.ResultsThe CTC positivity rate in patients with tumors before radiotherapy was 98.44%. Epithelial–mesenchymal CTCs (EMCTCs) were more common in patients with lung adenocarcinoma and squamous carcinoma than in patients with small cell lung cancer (P = 0.027). The total CTCs (TCTCs), EMCTCs, and mesenchymal CTCs (MCTCs) counts were significantly higher in patients with TNM stage III and IV tumors (P < 0.001, P = 0.005, and P < 0.001, respectively). The TCTCs and MCTCs counts were significantly higher in patients with an ECOG score of > 1 (P = 0.022 and P = 0.024, respectively). The TCTCs and EMCTCs counts before and after radiotherapy affected the overall response rate (ORR) (P < 0.05). TCTCs and ECTCs with positive hTERT expression were associated with the ORR of radiotherapy (P = 0.002 and P = 0.038, respectively), as were TCTCs with high hTERT expression (P = 0.012). ECOG score (P = 0.006) and post-radiation TCTCs count (P = 0.011) were independent factors for progression-free survival (PFS) and TNM stage (P = 0.054) and pre-radiation EMCTCs count (P = 0.009) were independent factors of overall survival (OS).ConclusionThis study showed a high rate of positive CTC detection in patients with lung cancer, and the number, subtype, and hTERT-positive expression of CTCs were closely related to patients’ ORR, PFS, and OS with radiotherapy. EMCTCs, hTERT-positive expression of CTCs are expected to be important biological indicators for predicting radiotherapy efficacy and the prognosis in patients with lung cancer. These results may be useful in improving disease stratification for future clinical trials and may help in clinical decision-making.

Clinical Validation of a Size-Based Microfluidic Device for Circulating Tumor Cell Isolation and Analysis in Renal Cell Carcinoma.

Renal cell carcinoma (RCC) presents as metastatic disease in one third of cases. Research on circulating tumor cells (CTCs) and liquid biopsies is improving the understanding of RCC biology and metastases formation. However, a standardized, sensitive, specific, and cost-effective CTC detection technique is lacking. The use of platforms solely relying on epithelial markers is inappropriate in RCC due to the frequent epithelial-mesenchymal transition that CTCs undergo. This study aimed to test and clinically validate RUBYchip™, a microfluidic label-free CTC detection platform, in RCC patients. The average CTC capture efficiency of the device was 74.9% in spiking experiments using three different RCC cell lines. Clinical validation was performed in a cohort of 18 patients, eight non-metastatic (M0), five metastatic treatment-naïve (M1TN), and five metastatic progressing-under-treatment (M1TP). An average CTC detection rate of 77.8% was found and the average (range) total CTC count was 6.4 (0-27), 101.8 (0-255), and 3.2 (0-10), and the average mesenchymal CTC count (both single and clustered cells) was zero, 97.6 (0-255), and 0.2 (0-1) for M0, M1TN, and M1TP, respectively. CTC clusters were detected in 25% and 60% of M0 and M1TN patients, respectively. These results show that RUBYchip™ is an effective CTC detection platform in RCC.

Comprehensive Profiling of Cancer-Associated Cells in the Blood of Breast Cancer Patients Undergoing Neoadjuvant Chemotherapy to Predict Pathological Complete Response.

Neoadjuvant chemotherapy (NAC) can affect pathological complete response (pCR) in breast cancers; the resection that follows identifies patients with residual disease who are then offered second-line therapies. Circulating tumor cells (CTCs) and cancer-associated macrophage-like cells (CAMLs) in the blood can be used as potential biomarkers for predicting pCR before resection. CTCs are of epithelial origin that undergo epithelial-to-mesenchymal transition to become more motile and invasive, thereby leading to invasive mesenchymal cells that seed in distant organs, causing metastasis. Additionally, CAMLs in the blood of cancer patients are reported to either engulf or aid the transport of cancer cells to distant organs. To study these rare cancer-associated cells, we conducted a preliminary study where we collected blood from patients treated with NAC after obtaining their written and informed consent. Blood was collected before, during, and after NAC, and Labyrinth microfluidic technology was used to isolate CTCs and CAMLs. Demographic, tumor marker, and treatment response data were collected. Non-parametric tests were used to compare pCR and non-pCR groups. Univariate and multivariate models were used where CTCs and CAMLs were analyzed for predicting pCR. Sixty-three samples from 21 patients were analyzed. The median(IQR) pre-NAC total and mesenchymal CTC count/5 mL was lower in the pCR vs. non-pCR group [1(3.5) vs. 5(5.75); p = 0.096], [0 vs. 2.5(7.5); p = 0.084], respectively. The median(IQR) post-NAC CAML count/5 mL was higher in the pCR vs. non-pCR group [15(6) vs. 6(4.5); p = 0.004]. The pCR group was more likely to have >10 CAMLs post-NAC vs. non-pCR group [7(100%) vs. 3(21.4%); p = 0.001]. In a multivariate logistic regression model predicting pCR, CAML count was positively associated with the log-odds of pCR [OR = 1.49(1.01, 2.18); p = 0.041], while CTCs showed a negative trend [Odds Ratio (OR) = 0.44(0.18, 1.06); p = 0.068]. In conclusion, increased CAMLs in circulation after treatment combined with lowered CTCs was associated with pCR.

Dynamics of CXCR4 positive circulating tumor cells in prostate cancer patients during radiotherapy.

Ablative radiotherapy is a highly efficient treatment modality for patients with metastatic prostate cancer (PCa). However, a subset of patients does not respond. Currently, this subgroup with bad prognosis cannot be identified before disease progression. We hypothesize that markers indicative of radioresistance, stemness and/or bone tropism may have a prognostic potential to identify patients profiting from metastases-directed radiotherapy. Therefore, circulating tumor cells (CTCs) were analyzed in patients with metastatic PCa (n=24) during radiotherapy with CellSearch, multicolor flow cytometry and imaging cytometry. Analysis of copy-number alteration indicates a polyclonal CTC population that changes after radiotherapy. CTCs were found in 8 out of 24 patients (33.3%) and were associated with a shorter time to biochemical progression after radiotherapy. Whereas the total CTC count dropped after radiotherapy, a chemokine receptor CXCR4-expressing subpopulation representing 28.6% of the total CTC population remained stable up to 3 months. At once, we observed higher chemokine CCL2 plasma concentrations and proinflammatory monocytes. Additional functional analyses demonstrated key roles of CXCR4 and CCL2 for cellular radiosensitivity, tumorigenicity and stem-like potential in vitro and in vivo. Moreover, a high CXCR4 and CCL2 expression was found in bone metastasis biopsies of PCa patients. In summary, panCK+ CXCR4+ CTCs may have a prognostic potential in patients with metastatic PCa treated with metastasis-directed radiotherapy.

Association of circulating tumor cells and IMP3 expression with metastasis of osteosarcoma.

Circulating tumor cells (CTCs) have been identified as a prognostic biomarker of tumors such as breast cancer and nasopharyngeal carcinoma, because they are obtained through a simple and noninvasive blood draw or liquid biopsy, but its clinical significance in osteosarcoma is still unclear. In this study, we analyzed the relationship between CTCs and clinicopathological features and discussed whether CTCs could be used as a biomarker for metastasis in osteosarcoma. We enrolled 50 osteosarcoma patients with Enneking Stage IIB and Stage III and detected CTCs in 5ml of peripheral blood samples collected from patients using the Canpatrol® CTC detection platform. Subsequently, multiplex RNA in situ hybridization (RNA-ISH) based on various molecular markers was performed to identify and classify CTCs. The relationships between clinical pathological features and CTC counts, subtypes (epithelial type, E type; hybrid epithelial/mesenchymal type, H type; mesenchymal type, M type), and insulin-like growth factor mRNA-binding protein 3 (IMP3) expression in CTCs were analyzed. CTCs were detected in 86% (43/50) of the osteosarcoma patients. The CTC counts, especially the total CTCs and H-type CTCs, signifcantly differed between Enneking Stage IIB and Stage III patients (P < 0.05). No significant differences were observed between the CTC count or type and other clinicopathological features (P > 0.05). There were significant differences in the expression of IMP3 in different types of CTCs, and the IMP3 positive rates in E/H/M type CTCs were 38.4, 65.6, and 62.0%, respectively (P < 0.001). Receiver operating characteristic (ROC) curve analysis showed that IMP3-positive CTC count had the best performance for diagnostic metastasis, with the largest area under the curve of 0.873 and cutoff value of four cells/5ml blood (sensitivity = 87.5%; specificity = 82.4%). Serial CTC monitoring in one patient suggested that total CTCs and H-type CTCs were associated with disease progression. This study demonstrates that the CTCs, especially the IMP3-positive CTCs and H/M-type CTCs, are related to the metastasis of osteosarcoma.

Quantification and Characterization of CTCs and Clusters in Pancreatic Cancer by Means of the Hough Transform Algorithm

Circulating Tumor Cells (CTCs) are considered a prognostic marker in pancreatic cancer. In this study we present a new approach for counting CTCs and CTC clusters in patients with pancreatic cancer using the IsofluxTM System with the Hough transform algorithm (Hough-IsofluxTM). The Hough-IsofluxTM approach is based on the counting of an array of pixels with a nucleus and cytokeratin expression excluding the CD45 signal. Total CTCs including free and CTC clusters were evaluated in healthy donor samples mixed with pancreatic cancer cells (PCCs) and in samples from patients with pancreatic ductal adenocarcinoma (PDAC). The IsofluxTM System with manual counting was used in a blinded manner by three technicians who used Manual-IsofluxTM as a reference. The accuracy of the Hough-IsofluxTM approach for detecting PCC based on counted events was 91.00% [84.50, 93.50] with a PCC recovery rate of 80.75 ± 16.41%. A high correlation between the Hough-IsofluxTM and Manual-IsofluxTM was observed for both free CTCs and for clusters in experimental PCC (R2 = 0.993 and R2 = 0.902 respectively). However, the correlation rate was better for free CTCs than for clusters in PDAC patient samples (R2 = 0.974 and R2 = 0.790 respectively). In conclusion, the Hough-IsofluxTM approach showed high accuracy for the detection of circulating pancreatic cancer cells. A better correlation rate was observed between Hough-IsofluxTM approach and with the Manual-IsofluxTM for isolated CTCs than for clusters in PDAC patient samples.

The mesenchymal circulating tumor cells as biomarker for prognosis prediction and supervision in hepatocellular carcinoma

PurposeHepatocellular carcinoma (HCC) is one of the most common cancers and a leading cause of death worldwide. Accurate prognosis prediction tools are urgently needed. While the use of circulating tumor cells (CTCs) as prognostic prediction tool has a clear potential.MethodsWe established a comprehensive, negative enrichment-based strategy for CTCs analysis in patients with HCC, involving identification of epithelial CTCs (E-CTCs) and mesenchymal CTCs (M-CTCs) through specific biomarker. This strategy was performed in 127 HCC cases, 21 nonmalignant liver disease (NMLD) patients and 42 health control to analyze the relevance between CTCs and tumor recurrence.ResultsThe total CTC number and M-CTC percent were positively correlated with tumor malignancy and high recurrence risk. Individually, preoperative total CTC number and M-CTC percent could robustly distinguish relapse cases from those with no relapse, with sensitivity of 80.95% and 90.48%, specificity of 74.12% and 84.71%, respectively. Levels of preoperative total CTC number and M-CTC percent can both be regarded as independent risk factors for HCC with early recurrence (P = 0.0053, P < 0.0001), and are both significantly correlated with worse recurrence-free survival (RFS) (log rank P < 0.0001; HR 7.78, 95% CI = 3.59–16.87; log rank P < 0.0001; HR 24.4, 95% CI = 8.67–68.77). The levels of total CTC number and M-CTC number had higher effectiveness than alpha fetal protein (AFP) in HCC longitudinal supervision (77.78% vs 88.89% vs 22.22%).ConclusionPreoperative and postoperative CTCs with higher effectiveness than AFP in prognosis prediction and recurrence supervision, indicating that CTCs could work as the biomarker for HCC clinical management.