Endothelial progenitor cells are associated with response to chemotherapy in human non-small-cell lung cancer

Endothelial progenitor cells as an angiogenic biomarker for the diagnosis and prognosis of lung cancer

Background

Angiogenesis is mediated by endothelial progenitor cells (EPCs) derived from bone-marrow. In this prospective study, we tried to investigate the clinical utility of circulating EPCs in lung cancer (LC) patients.

Materials and methods

Flow cytometry technique was used to assess circulating EPCs according to the immuno-phenotype CD45- CD34+ CD133+ CD146+ mononuclear cells. Sixty patients and 30 controls were included in this prospective study.

Results

The mean of baseline EPC numbers was significantly higher in LC patients than in controls (p =0.003). Pretreatment EPC values were significantly correlated with primary tumor size (p = 0.05) and tumor response (p = 0.04). Receiver operating characteristics (ROC) curves were plotted to discriminate EPC numbers between patients and controls. Using ROC analysis, the optimal cutoff value was 125 cells/mL with a sensitivity and a specificity for baseline EPCs of 76.7% and 63.3%, respectively. According to this cutoff value, basal EPC values were significantly correlated with primary tumor size (p = 0.047) and response to chemotherapy (p = 0.034). High EPC levels were significantly associated with longer progression-free survival (PFS) and overall survival (OS) duration (p = 0.0043 and p = 0.02, respectively).

Conclusion

Increased baseline EPC values seem to be a useful biomarker for the prediction of prognosis and tumor response in LC patients. Furthermore, high EPC levels at diagnosis might be an indicator of tumor growth and longer survival in LC patients.

Deep radiomic model based on the sphere-shell partition for predicting treatment response to chemotherapy in lung cancer

BACKGROUND

The prognosis of chemotherapy is important in clinical decision-making for non-small cell lung cancer (NSCLC) patients.

OBJECTIVES

To develop a model for predicting treatment response to chemotherapy in NSCLC patients from pre-chemotherapy CT images.

MATERIALS AND METHODS

This retrospective multicenter study enrolled 485 patients with NSCLC who received chemotherapy alone as a first-line treatment. Two integrated models were developed using radiomic and deep-learning-based features. First, we partitioned pre-chemotherapy CT images into spheres and shells with different radii around the tumor (0-3, 3-6, 6-9, 9-12, 12-15 mm) containing intratumoral and peritumoral regions. Second, we extracted radiomic and deep-learning-based features from each partition. Third, using radiomic features, five sphere-shell models, one feature fusion model, and one image fusion model were developed. Finally, the model with the best performance was validated in two cohorts.

RESULTS

Among the five partitions, the model of 9-12 mm achieved the highest area under the curve (AUC) of 0.87 (95% confidence interval: 0.77-0.94). The AUC was 0.94 (0.85-0.98) for the feature fusion model and 0.91 (0.82-0.97) for the image fusion model. For the model integrating radiomic and deep-learning-based features, the AUC was 0.96 (0.88-0.99) for the feature fusion method and 0.94 (0.85-0.98) for the image fusion method. The best-performing model had an AUC of 0.91 (0.81-0.97) and 0.89 (0.79-0.93) in two validation sets, respectively.

CONCLUSIONS

This integrated model can predict the response to chemotherapy in NSCLC patients and assist physicians in clinical decision-making.

Predicting chemotherapy response in non-small-cell lung cancer via computed tomography radiomic features: Peritumoral, intratumoral, or combined?

Purpose

This study aims to evaluate the ability of peritumoral, intratumoral, or combined computed tomography (CT) radiomic features to predict chemotherapy response in non-small cell lung cancer (NSCLC).

Methods

After excluding subjects with incomplete data or other types of treatments, 272 (Dataset 1) and 43 (Dataset 2, external validation) NSCLC patients who were only treated with chemotherapy as the first-line treatment were enrolled between 2015 and 2019. All patients were divided into response and nonresponse based on the response evaluation criteria in solid tumors, version 1.1. By using 3D slicer and morphological operations in python, the intra- and peritumoral regions of lung tumors were segmented from pre-treatment CT images (unenhanced) and confirmed by two experienced radiologists. Then radiomic features (the first order, texture, shape, et al.) were extracted from the above regions of interest. The models were trained and tested in Dataset 1 and further validated in Dataset 2. The performance of models was compared using the area under curve (AUC), confusion matrix, accuracy, precision, recall, and F1-score.

Results

The radiomic model using features from the peritumoral region of 0–3 mm outperformed that using features from 3–6, 6–9, 9–12 mm peritumoral region, and intratumoral region (AUC: 0.95 versus 0.87, 0.86, 0.85, and 0.88). By the fusion of features from 0–3 and 3–6 mm peritumoral regions, the logistic regression model achieved the best performance, with an AUC of 0.97. This model achieved an AUC of 0.85 in the external cohort. Moreover, among the 20 selected features, seven features differed significantly between the two groups (p < 0.05).

Conclusions

CT radiomic features from both the peri- and intratumoral regions can predict chemotherapy response in NSCLC using machine learning models. Combined features from two peritumoral regions yielded better predictions.

Modern ideas about the origin, features of morphology, prognostic and predictive significance of tumor vessels

The review presents modern ideas about the origin of tumor vessels and the features of their morphology. The various approaches to the classification of tumor vessel types and to the assessment of their clinical and prognostic significance are described. Also, the main problems associated with the use of angiogenesis blockers in the treatment of malignancies and their possible solutions are reflected in the review.

Combination of Peri- and Intratumoral Radiomic Features on Baseline CT Scans Predicts Response to Chemotherapy in Lung Adenocarcinoma

Purpose

To identify the role of radiomics texture features both within and outside the nodule in predicting (a) time to progression (TTP) and overall survival (OS) as well as (b) response to chemotherapy in patients with non-small cell lung cancer (NSCLC).

Materials and Methods

Data in a total of 125 patients who had been treated with pemetrexed-based platinum doublet chemotherapy at Cleveland Clinic were retrospectively analyzed. The patients were divided randomly into two sets with the constraint that there were an equal number of responders and nonresponders in the training set. The training set comprised 53 patients with NSCLC, and the validation set comprised 72 patients. A machine learning classifier trained with radiomic texture features extracted from intra- and peritumoral regions of non-contrast-enhanced CT images was used to predict response to chemotherapy. The radiomic risk-score signature was generated by using least absolute shrinkage and selection operator with the Cox regression model; association of the radiomic signature with TTP and OS was also evaluated.

Results

A combination of radiomic features in conjunction with a quadratic discriminant analysis classifier yielded a mean maximum area under the receiver operating characteristic curve (AUC) of 0.82 ± 0.09 (standard deviation) in the training set and a corresponding AUC of 0.77 in the independent testing set. The radiomics signature was also significantly associated with TTP (hazard ratio [HR], 2.8; 95% confidence interval [CI]: 1.95, 4.00; P < .0001) and OS (HR, 2.35; 95% CI: 1.41, 3.94; P = .0011). Additionally, decision curve analysis demonstrated that in terms of clinical usefulness, the radiomics signature had a higher overall net benefit in prediction of high-risk patients to receive treatment than the clinicopathologic measurements.

Conclusion

This study suggests that radiomic texture features extracted from within and around the nodule on baseline CT scans are (a) predictive of response to chemotherapy and (b) associated with TTP and OS for patients with NSCLC.© RSNA, 2019Supplemental material is available for this article.

The evaluation of circulating endothelial progenitor cells and related angiogenic markers as prognostic factors in soft-tissue tumors

INTRODUCTION

Neovascularisation is a critical step in the progression of malignant tumors. Circulating endothelial progenitor cells (cEPC) have been proposed as surrogate markers of vasculogenesis in malignancies. In this project, we studied the impact of tumor-specific therapy on cEPC and associated angiogenic factors in patients with soft tissue tumors.

MATERIALS AND METHODS

Fifty-three patients with soft tissue tumors (25 soft tissue sarcomas, 19 GIST, 9 desmoids) and 15 healthy controls were included. Blood samples were obtained at two time points, before and 8 weeks after start of tumor-specific therapy. Peripheral blood mononuclear cells (PBMCs) were isolated. cEPCs were characterised as CD34⁺, CD133⁺, CD45^dim, CD31⁺ and vascular endothelial growth factor 2 (VEGFR-2) positive cells. Serum concentrations of VEGF-A and angiopoetin-2 were determined by enzyme-linked immunosorbent assay.

RESULTS

VEGF-A and Ang-2 concentrations were significantly higher in tumor patients than in healthy controls in both samples (p < .01). Sarcoma patients with progressive disease developed a significant increase in cEPC levels between the two blood samples compared to those with stable disease (p = .002). GIST patients with progressive tumor or metastatic disease showed significant increase in VEGF-A values (p = .01).

DISCUSSION

The pre-treatment values of the angiogenic markers did not correlate with the clinical course of the disease. However, cEPCs levels were significantly higher in sarcoma patients with progressive disease compared to those with stable disease and should be further evaluated as early markers of disease progression in sarcoma patients. VEGF-A and angiopoetin-2 clearly play a role as mediators of the vasculogenesis contributing to tumor progression.

Clinical significance of 5-(and 6)-carboxyfluorescein diacetate succinimidyl ester-labeled microspheres for detecting endothelial progenitor cells in human peripheral blood

The aims of the present study were to establish a single-platform flow cytometry method using 5-(and 6)-carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled microspheres as the reference for determining endothelial progenitor cell (EPC) number and to evaluate the efficacy of this detection method. Single-platform flow cytometry was used to count cell numbers using CFSE-stained fluorescent microspheres as the internal reference and the EPC numbers in specimens using this novel method were compared with an in vitro clonogenic counting assay. The results of the two counting methods were consistent and compared with the in vitro clonogenic counting assay, the time and cost of the novel method was markedly reduced, as were the corresponding technical requirements. The present findings indicated that single-platform flow cytometry, with CFSE-labeled microspheres as the reference, provides faster and improved detection of EPCs in human peripheral blood specimens, with reduced time and cost, making it more suitable for routine clinical application.

Flow cytometric analysis of circulating endothelial cells and endothelial progenitors for clinical purposes in oncology: A critical evaluation

Malignant tumors are characterized by uncontrolled cell growth and metastatic spread, with a pivotal importance of the phenomenon of angiogenesis. For this reason, research has focused on the development of agents targeting the vascular component of the tumor microenvironment and regulating the angiogenic switch. As a result, the therapeutic inhibition of angiogenesis has become an important component of anticancer treatment, however, its utility is partly limited by the lack of an established methodology to assess its efficacy in vivo. Circulating endothelial cells (CECs), which are rare in healthy subjects and significantly increased in different tumor types, represent a promising tool for monitoring the tumor clinical outcome and the treatment response. A cell population circulating into the blood also able to form endothelial colonies in vitro and to promote vasculogenesis is represented by endothelial progenitor cells (EPCs). The number of both of these cell types is extremely low and they cannot be identified using a single marker, therefore, in absence of a definite consensus on their phenotype, require discrimination using combinations of antigens. Multiparameter flow cytometry (FCM) is ideal for rapid processing of high numbers of cells per second and is commonly utilized to quantify CECs and EPCs, however, remains technically challenging since there is as yet no standardized protocol for the identification and enumeration of these rare events. Methodology in studies on CECs and/or EPCs as clinical biomarkers in oncology is heterogeneous and data have been obtained from different studies leading to conflicting conclusions. The present review presented a critical review of the issues that limit the comparability of results of the most significant studies employing FCM for CEC and/or EPC detection in patients with cancer.

Meta-Analysis of Circulating Endothelial Cells and Circulating Endothelial Progenitor Cells as Prognostic Factors in Lung Cancer

BACKGROUND

The aim of this study was to analyze the prognostic implications of pretreatment circulating endothelial cells (CECs) and circulating endothelial progenitor cells (CEPCs) for the survival of patients with lung cancer.

MATERIALS AND METHODS

Relevant literature was identified using Medline and EMBASE. Patient clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CEC and CEPC positive rates before treatment were extracted. STATA 12.0 was used for our analysis and assessment of publication bias.

RESULTS

A total of 13 articles (8 for CEC and 5 for CEPC, n=595 and n=244) were pooled for the global meta-analysis. The odds ratio (OR) for OS predicted by pretreatment CECs was 1.641 [0.967, 2.786], while the OR for PFS was 1.168 [0.649, 2.100]. The OR for OS predicted by pretreatment CEPCs was 12.673 [5.274, 30.450], while the OR for PFS was 4.930 [0.931, 26.096]. Subgroup analyses were conducted according to clinical staging. Odds ratio (OR) showed the high level of pretreatment CECs only correlated with the OS of patients with advanced lung cancer (stage III-IV).

CONCLUSIONS

High counts of CECs seem to be associated only with worse 1-year OS in patients with lung cancer, while high level of pretreatment CEPCs correlate with both worse PFS and OS.

Endothelial progenitor cells--potential new avenues to improve neoangiogenesis and reendothelialization

The term endothelial progenitor cell (EPC) was established more than 10 years ago and is used to refer to a group of circulating cells that display endothelial lineage qualities and are able to home to areas of ischemia or vascular injury and to facilitate the repair of damaged blood vessels or develop new vessels as needed. This chapter reviews the current lineage relationships among all the cells called EPC and will clear the terminology used in EPC research. Furthermore, an overview of the clinical and in vitro research, as well as cytokine and drug interactions and potential EPC applications, is given.

Clinical value of circulating endothelial cells and of soluble CD146 levels in patients undergoing surgery for non-small cell lung cancer

Background:

Previous studies indicate that endothelial injury, as demonstrated by the presence of circulating endothelial cells (CECs), may predict clinical outcome in cancer patients. In addition, soluble CD146 (sCD146) may reflect activation of angiogenesis. However, no study has investigated their combined clinical value in patients undergoing resection for non-small cell lung cancer (NSCLC).

Methods:

Data were collected from preoperative blood samples from 74 patients who underwent resection for NSCLC. Circulating endothelial cells were defined, using the CellSearch Assay, as CD146+CD105+CD45−DAPI+. In parallel, sCD146 was quantified using an ELISA immunoassay. These experiments were also performed on a group of 20 patients with small-cell lung cancer, 60 healthy individuals and 23 patients with chronic obstructive pulmonary disease.

Results:

The CEC count and the plasma level of sCD146 were significantly higher in NSCLC patients than in the sub-groups of controls (P<0.001). Moreover, an increased CEC count was associated with higher levels of sCD146 (P=0.010). Both high CEC count and high sCD146 plasma level at baseline significantly correlated with shorter progression-free survival (P<0.001, respectively) and overall survival (P=0.005; P=0.009) of NSCLC patients.

Conclusions:

The present study provides supportive evidence to show that both a high CEC count and a high sCD146 level at baseline correlate with poor prognosis and may be useful for the prediction of clinical outcome in patients undergoing surgery for NSCLC.

Baseline and post-surgery endothelial progenitor cell levels in patients with early-stage non-small-cell lung carcinoma: impact on cancer recurrence and survival

OBJECTIVES

Endothelial progenitor cells (EPCs) are believed to play a role in promoting abnormal vascularization in neoplastic sites. We measured the number of circulating EPCs in treatment-naïve patients with early non-small-cell lung cancer (NSCLC) and healthy controls. The prospective influence of baseline and post-surgery EPC levels on cancer recurrence and survival was investigated.

METHODS

Circulating EPCs were quantified by FACS analysis in 34 patients with Stage I-II NSCLC and 68 healthy age- and sex-matched controls. Measurement of EPCs was repeated 48 h after thoracic surgery and at the hospital discharge. Cancer recurrence and survival was evaluated after 446 ± 106 days of follow-up (range 182-580 days).

RESULTS

The base 10 logarithmic [log] number of circulating EPCs was comparable between patients with NSCLC and controls [mean ± standard deviation (SD): 2.3 ± 0.32 vs 2.3 ± 0.26 n/ml, P = 0.776]. In regression analysis, smoking status [standardized coefficient beta (β) = -0.26, 95% confidence interval (CI) for B -0.29/-0.03, P = 0.014] and systolic blood pressure [β = -0.23, 95% CI for B -0.011/-0.001, P = 0.018] were independent predictors of the number of EPCs, irrespective of the NSCLC status. The mean number of EPCs did not change after surgical treatment. However, a post-surgery EPC increase was observed in 44% patients. Patients with a 48 h post-surgery EPC increase had a higher rate of cancer recurrence/death than patients with either stable or decreased post-surgery EPC levels [hazard ratio (HR) 4.4, 95% CI 1.1-17.3; P = 0.032], irrespective of confounders.

CONCLUSIONS

Circulating EPC levels are comparable between patients with early-stage NSCLC and healthy controls. Overall, surgical cancer resection was not associated with a significant early EPC change. However, an early post-surgery EPC increase is able to predict an increased risk of cancer recurrence and death.

Circulating endothelial progenitor cells in gynaecological cancer

Objectives

To compare the frequency and absolute numbers of circulating endothelial progenitor cells (EPCs) in healthy control subjects and patients with gynaecological cancer, and to test the hypothesis that cancer treatment lowers EPC numbers.

Methods

Patients with cervical or ovarian cancer and healthy control subjects provided peripheral blood samples for the isolation of mononuclear cells. EPCs were identified by quadruple immunofluorescence staining and flow cytometry as CD45–/CD34+/CD133+/vascular endothelial growth factor receptor 2 (VEGFR2)+ cells.

Results

In total, 28 participants were enrolled. Circulating EPCs were present at higher frequencies (and in greater absolute numbers) in patients with cervical or ovarian cancer ( n = 14) than in controls ( n = 14). Concurrent chemoradiation therapy or surgery significantly reduced the frequency and number of EPCs in patients with gynaecological cancer, compared with pretreatment levels.

Conclusions

EPC levels decline throughout cancer treatment; their measurement may therefore be a useful surrogate marker to monitor treatment response.

Endothelial precursor cells promote angiogenesis in hepatocellular carcinoma

AIM: To investigate the role of bone marrow-derived endothelial progenitor cells (EPCs) in the angiogenesis of hepatocellular carcinoma (HCC).

METHODS: The bone marrow of HCC mice was reconstructed by transplanting green fluorescent protein (GFP) + bone marrow cells. The concentration of circulating EPCs was determined by colony-forming assays and fluorescence-activated cell sorting. Serum and tissue levels of vascular endothelial growth factor (VEGF) and colony-stimulating factor (CSF) were quantified by enzyme-linked immunosorbent assay. The distribution of EPCs in tumor and tumor-free tissues was detected by immunohistochemistry and real-time polymerase chain reaction. The incorporation of EPCs into hepatic vessels was examined by immunofluorescence and immunohistochemistry. The proportion of EPCs in vessels was then calculated.

RESULTS: The HCC model was successful established. The flow cytometry analysis showed the mean percentage of CD133CD34 and CD133VEGFR2 double positive cells in HCC mice was 0.45% ± 0.16% and 0.20% ± 0.09% respectively. These values are much higher than in the sham-operation group (0.11% ± 0.13%, 0.05% ± 0.11%, n = 9) at 14 d after modeling. At 21 d, the mean percentage of circulating CD133CD34 and CD133VEGFR2 cells is 0.23% ± 0.19%, 0.25% ± 0.15% in HCC model vs 0.05% ± 0.04%, 0.12% ± 0.11% in control. Compared to the transient increase observed in controls, the higher level of circulating EPCs were induced by HCC. In addition, the level of serum VEGF and CSF increased gradually in HCC, reaching its peak 14 d after modeling, then slowly decreased. Consecutive sections stained for the CD133 and CD34 antigens showed that the CD133+ and CD34+ VEGFR2 cells were mostly recruited to HCC tissue and concentrated in tumor microvessels. Under fluorescence microscopy, the bone-marrow (BM)-derived cells labeled with GFP were concentrated in the same area. The relative levels of CD133 and CD34 gene expression were elevated in tumors, around 5.0 and 3.8 times that of the tumor free area. In frozen liver sections from HCC mice, cells co-expressing CD133 and VEGFR2 were identified by immunohistochemical staining using anti-CD133 and VEGFR2 antibodies. In tumor tissue, the double-positive cells were incorporated into vessel walls. In immunofluorescent staining. These CD31 and GFP double positive cells are direct evidence that tumor vascular endothelial cells (VECs) come partly from BM-derived EPCs. The proportion of GFP CD31 double positive VECs (out of all VECs) on day 21 was around 35.3% ± 21.2%. This is much higher than the value recorded on day 7 group (17.1% ± 8.9%). The expression of intercellular adhesion molecule 1, vascular adhesion molecule 1, and VEGF was higher in tumor areas than in tumor-free tissues.

CONCLUSION: Mobilized EPCs were found to participate in tumor vasculogenesis of HCC. Inhibiting EPC mobilization or recruitment to tumor tissue may be an efficient strategy for treating HCC.