Number of circulating endothelial progenitor cells and intratumoral microvessel density in non-small cell lung cancer patients: differences in angiogenic status between adenocarcinoma histologic subtypes

A decision support framework for postoperative radiotherapy in patients with pathological N2 non-small cell lung cancer

INTRODUCTION

Postoperative radiotherapy (PORT) plays a highly controversial role in pathological N2 (pN2) non-small cell lung cancer (NSCLC) disease. Recent studies reveal that not all patients can benefit from PORT. Further research is needed to identify predictors of PORT.

METHODS

A total of 1044 pathologic stage T1-3N2M0 NSCLC patients were analyzed. Risk factors of distant metastasis were identified by the log-rank tests and the multivariable Cox models. We integrated risk factors of distant metastasis and our previously published loco-regional recurrence (LRR) related prognostic index into a decision support framework (DSF) to predict the outcomes of PORT. An independent cohort was used to validate the DSF.

RESULTS

We defined patients with more than two of three identified LRR-related features (heavy cigarette smoking history, clinical N2 status, and more than four positive lymph nodes) as a high LRR risk group. We found the high-intermediate-risk histological type (with micropapillary and/or solid components) was associated with a higher risk of distant metastasis (HR=1.207, 95% CI 1.062 to 1.371, P=0.0129), but not LRR. We built the DSF by combining these two types of features. Patients were stratified into four groups by using the DSF. PORT significantly improved OS only in the subgroup without high-risk histological features (without micropapillary or solid components) and with a high risk for LRR (three-year OS: 66.7% in the PORT group vs. 50.2% in the non-PORT group; P=0.023).

CONCLUSIONS

A particular pN2 subgroup with a high risk of LRR and without micropapillary or solid components could benefit from PORT.

Evaluation of Intra-Tumoral Vascularization in Hepatocellular Carcinomas

Intratumoral neovascularization has intricate effects on tumor growth, metastasis, and treatment. Over the last 30 years, Microvessel density (MVD) has been the standard method for laboratory and clinical evaluation of angiogenesis. Hepatocellular carcinoma (HCC) is a typical hypervascularized tumor, and the predictive value of MVD for prognosis is still controversial. According to previous viewpoints, this has been attributed to the determination of hotspot, counting methods, vascular endothelial markers, and different definitions of high and low vascular density; however, the heterogeneity of tumor angiogenesis patterns should be factored. The breakthroughs in artificial intelligence and algorithm can improve the objectivity and repeatability of MVD measurement, thus saving a lot of manpower. Presently, anti-angiogenesis therapy is the only effective systematic treatment for liver cancer, and the use of imaging technology-assisted MVD measurement is expected to be a reliable index for evaluating the curative effect. MVD in multinodular hepatocellular carcinoma represents a subject area with huge understudied potential, and exploring it might advance our understanding of tumor heterogeneity.

Prognostic value of radiomic analysis of iodine overlay maps from dual-energy computed tomography in patients with resectable lung cancer

OBJECTIVES

To investigate whether radiomics on iodine overlay maps from dual-energy computed tomography (DECT) can predict survival outcomes in patients with resectable lung cancer.

METHODS

Ninety-three lung cancer patients eligible for curative surgery were examined with DECT at the time of diagnosis. The median follow-up was 60.4 months. Radiomic features of the entire primary tumour were extracted from iodine overlay maps generated by DECT. A Cox proportional hazards regression model was used to determine independent predictors of overall survival (OS) and disease-free survival (DFS), respectively.

RESULTS

Forty-two patients (45.2%) had disease recurrence and 39 patients (41.9%) died during the follow-up period. The mean DFS was 49.8 months and OS was 55.2 months. Univariate analysis revealed that significant predictors of both OS and DFS were stage and radiomic parameters, including histogram energy, histogram entropy, grey-level co-occurrence matrix (GLCM) angular second moment, GLCM entropy and homogeneity. The multivariate analysis identified stage and entropy as independent risk factors predicting both OS (stage, hazard ratio (HR) = 2.020 [95% CI 1.014-4.026], p = 0.046; entropy, HR = 1.543 [95% CI 1.069-2.228], p = 0.021) and DFS (stage, HR = 2.132 [95% CI 1.060-4.287], p = 0.034; entropy, HR = 1.497 [95% CI 1.031-2.173], p = 0.034). The C-index showed that adding entropy improved prediction of OS compared to stage only (0.720 and 0.667, respectively; p = 0.048).

CONCLUSIONS

Radiomic features extracted from iodine overlay map reflecting heterogeneity of tumour perfusion can add prognostic information for patients with resectable lung cancer.

KEY POINTS

• Radiomic feature (histogram entropy) from DECT iodine overlay maps was an independent risk factor predicting both overall survival and disease-free survival. • Adding histogram entropy to clinical stage improved prediction of overall survival compared to stage only (0.720 and 0.667, respectively; p = 0.048). • DECT can be a good option for comprehensive pre-operative evaluation in cases of resectable lung cancer.

Roles of circulating endothelial progenitor cells and endothelial cells in gastric carcinoma

The present study aimed to investigate the role of endothelial progenitor cells (EPCs) and endothelial cells (ECs) in the peripheral blood of patients with gastric cancer (GC), and to investigate vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in GC tissues. First, 6 ml peripheral blood with added anticoagulant was collected from each of the 42 patients with GC, followed by determination of the number of EPCs and ECs by flow cytometry using the surface markers cluster of differentiation (CD)34^brightCD133⁺CD31⁺CD45^dim and CD34^dimCD133⁻CD31^brightCD45⁻, respectively. VEGF expression in patients with GC was detected by the streptomycin avidin-peroxidase immunohistochemical method, and MVD was calculated using the marker CD34. EPC and EC levels were positively associated with VEGF expression level, as well as with MVD. VEGF expression was positive in 66.67% GC cases, and its level was significantly associated with tumor-node-metastasis (TNM) stage, invasion depth and lymph-node metastasis (P<0.05). VEGF expression level was also positively associated with MVD. MVD in GC was significantly larger than that in normal tissue (P<0.01), and it was significantly associated with TNM stage (P<0.05), invasion depth (P<0.01) and lymph-node metastasis (P<0.01). EPCs in the peripheral blood have an important role in GC development, and may be a promising indicator of GC diagnosis and prognosis.

Microvascular proliferation is associated with aggressive tumour features and reduced survival in lung adenocarcinoma

Despite new treatment options in lung cancer, there is still a need for better biomarkers to assist in therapy decisions. Angiogenesis has been associated with tumour growth and dissemination, and the vascular proliferation index (VPI) is a valuable prognostic marker in other tumours. Nestin, a marker of immature endothelium, was previously applied in combination with Ki67 for proliferating endothelium as a novel marker (Nestin‐Ki67) of ongoing angiogenesis. Here, the prevalence and prognostic impact of vascular proliferation on lung cancer‐specific survival (LCSS) in lung adenocarcinomas was studied. Selected tumour slides from a cohort of 210 patients treated surgically for adenocarcinoma at Haukeland University Hospital (Norway) from 1993 to 2010 were stained for Nestin‐Ki67. VPI, the ratio between the density of proliferating vessels and the overall microvessel density were used, and the cut‐off value was set at 4.4% (upper quartile). High VPI was associated with the presence of blood vessel invasion (p = 0.007) and tumour necrosis (p = 0.007). Further, high VPI was significantly associated with reduced LCSS (p = 0.020). By multivariate analysis, VPI remained an independent prognostic factor for reduced LCSS (HR 1.7; 95% CI 1.04–2.68; p = 0.033) when adjusted for other prognostic clinico‐pathological features. In conclusion, microvessel proliferation assessed using the VPI was associated with aggressive tumour features such as blood vessel invasion and tumour necrosis and, independently, decreased LCSS. This marker should be further explored in separate cohorts, and in trials of anti‐angiogenesis therapy.

Histological features of malignancy correlate with growth patterns and patient outcome in lung adenocarcinoma

AIMS

Until the launch of the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society adenocarcinoma classification in 2011, there were no uniform histological grading criteria for pulmonary adenocarcinomas. The current classification highlights the prognostic importance of the various histological growth patterns observed in these morphologically heterogeneous neoplasias. In this study, we aimed to evaluate the classic histological parameters of malignancy in correlation with the growth patterns and patient outcomes in a series of 112 surgically operated stage I-IV lung adenocarcinomas.

METHODS AND RESULTS

Architectural growth pattern analysis was performed according to the current adenocarcinoma classification. Histological features including, for example, nuclear atypia, mitotic activity, tumour necrosis, and different patterns of invasion were assessed and correlated statistically with the architecture and the clinical data. A solid predominant histology was associated with increased levels of atypia (P = 0.027), mitotic activity (P < 0.001), necrosis (P < 0.001), and lymphovascular invasion (P = 0.001), and a non-predominant solid pattern was associated with intra-alveolar tumour spread (P = 0.004). The presence of a non-predominant lepidic tumour component showed inverse correlations with atypia (P = 0.002), mitotic rate (P = 0.009), and tumour necrosis (P < 0.001). Tumour size (P < 0.001), mitotic activity (P = 0.019), tumour necrosis (P = 0.002), lymphovascular invasion (P = 0.001) and visceral pleural involvement (P = 0.001) were all associated with reduced disease-specific survival.

CONCLUSIONS

The classic histological features of malignancy correlate with tumour architecture and patient outcome, confirming the prognostic value of the growth pattern analysis and questioning the need for a parallel grading system in pulmonary adenocarcinoma.

Microenvironmental changes in the progression from adenocarcinoma in situ to minimally invasive adenocarcinoma and invasive lepidic predominant adenocarcinoma of the lung

OBJECTIVES

Invasive lepidic predominant adenocarcinoma (LPA) of the lung is thought to progress in a stepwise fashion from adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA). The aim of this study was to investigate the microenvironmental changes during the development from AIS to LPA.

MATERIALS AND METHODS

Clinicopathological characteristics of AIS (n=51), MIA (n=59), LPA smaller than 3cm (LPA-S, n=113), and LPA larger than 3cm (LPA-L, n=47) were analyzed. We then evaluated the expression levels of epithelial-mesenchymal transition (EMT)-related molecules (E-cadherin, S100A4), invasion-related molecules (laminin-5, ezrin), stem-cell-related molecules (ALDH-1), and growth factor receptors (c-Met, EGFR) in cancer cells of each group (n=20). The number of tumor-promoting stromal cells, including podoplanin-positive cancer-associated fibroblasts (PDPN+ CAFs), CD204-positive tumor-associated macrophages (CD204+ TAMs), and CD34+ microvessel cells, were also analyzed.

RESULTS

No significant difference in these characteristics was found between LPA-S and LPA-L. Laminin-5 expression in the non-invasive carcinoma component of MIA was significantly higher than that of AIS (p<0.001). During the progression from MIA to LPA-S, the expression level of laminin-5 in the invasive carcinoma component was significantly elevated (p<0.01). Moreover, tumor-promoting stromal cells were more frequently recruited in the invasive area of LPA-S (PDPN+ CAFs; p<0.05, CD204+ TAMs; p<0.001, CD34+ microvessel; p<0.05). Ezrin expression in the invasive carcinoma component of LPA-L was significantly increased (p<0.05) compared to LPA-S; however, the number of tumor-promoting stromal cells were not different between these two groups.

CONCLUSION

Our current results indicated that microenvironmental molecular changes occur during the progression from MIA to LPA-S and suggested that this process may play an important role in disease progression from AIS to LPA.

Aggressive tumor microenvironment of solid predominant lung adenocarcinoma subtype harboring with epidermal growth factor receptor mutations

INTRODUCTION

Tumor microenvironment critically affects cancer progression. This study aimed to identify differences in microenvironments of lung adenocarcinomas with epidermal growth factor receptor (EGFR) mutations by histological subtypes.

METHODS

The study cohort included 214 lung adenocarcinomas harboring EGFR mutations. We analyzed clinicopathological characteristics of lepidic (LPA), papillary (PPA), acinar (APA), and solid-predominant adenocarcinoma (SPA) subtypes, and examined expression levels of EGFR, E-cadherin, ezrin, laminin-5, ALDH1, and PD-L1 in cancer cells, and of CD34, CD204, podoplanin (PDPN), and FoxP3 in stromal cells in 4 subtypes (n=20 each).

RESULTS

SPA displayed significantly more frequent lymph node metastasis, lymphovascular invasion, and worse prognosis than the other subtypes. Ezrin expression levels in SPA were also significantly higher than in LPA, PPA, or APA (P<0.05, all). Laminin-5 and PD-L1 expression levels in SPA were significantly higher than in LPA (P<0.01 for both) and PPA (P<0.01 for both) and tended to be higher than in APA (laminin-5: P=0.096, PD-L1: P=0.081). Furthermore, SPA displayed higher levels of PDPN (+) cancer-associated fibroblasts (P<0.01) and CD204 (+) tumor-associated macrophages (P<0.05) than the other subtypes.

CONCLUSION

Compared with other predominant subtypes with EGFR mutations, the microenvironment of SPA with EGFR mutations is characterized by cancer cells with higher invasive and immune evasion potential and more abundant stromal cells with tumor-promoting functions, which would contribute to the more aggressive behavior of SPA.

Circulating endothelial progenitor cell: a promising biomarker in clinical oncology

Human cancers are endowed with sustained vascularization capability, and their growth, invasion, and metastasis are vascularization dependent. Recently, accumulated body of evidence suggests that endothelial progenitor cells (EPCs) can support vasculogenesis and induce angiogenesis through paracrine mechanisms. In addition, numerous clinical studies have revealed the increase in the number of EPCs in the peripheral blood of cancer patients and demonstrated the correlation of circulating EPCs (CEPCs) with the clinical outcomes. This review highlights current enrichment procedures and methods for the detection of CEPCs and different biomarkers to identify CEPCs as well as the functions of EPCs in tumor vascularization. Furthermore, we systematically review available studies on the clinical relevance of CEPCs in cancer patients to explore the potential diagnostic and prognostic values of CEPCs. Although several contrasting results exist, CEPCs can conceivably serve as a promising biomarker for the early diagnosis, prognosis prediction, and treatment response indication in the future. Additionally, further well-designed clinical studies with larger sample size and unique, specific enumeration procedures are warranted to achieve further insight into the clinical implications of CEPCs.

Expression of osteopontin in non-small cell lung cancer and correlative relation with microvascular density

BACKGROUND AND OBJECTIVE

Lung cancer is one of the malignant diseases which most seriously threat humansurvival and development. This study aimed to assess osteopontin (OPN) expression in non-small cell lung cancer (NSCLC) and any relationship with clinicopathological features.

METHODS

Immunohistochemistry was used to determine OPN expression and microvascular density (MVD) in 120 cases of NSCLC also undergoing clinical assessment.

RESULTS

Moderately positive expression of OPN was found in 34.6% (41/120) and strong expression in 47.5% (57/120) of the NSCLCs; OPN expression in carcinomas was higher than in pericarcinoma tissues (P<0.05). While no obvious association was observed with NSCLC patient age, gender, maximum diameter of the tumor and pathological type, OPN expression was more commonly detected in poorly differentiated carcinoma tissue and lymph node metastasis as well as at advanced clinical stage (P<0.05); OPN expression in cancer tissue was positively correlated with MVD (r = 0.839, P = 0.000).

CONCLUSION

OPN plays an important role in promoting tumor angiogenesis and progress of NSCLCs and has the possibility to become the new target for therapy.

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.

Mechanisms of tumor resistance to small-molecule vascular disrupting agents: treatment and rationale of combination therapy

Small-molecule vascular disrupting agents (VDAs) target the established tumor blood vessels, resulting in rapidly and selectively widespread ischemia and necrosis of central tumor; meanwhile, blood flow in normal tissues is relatively unaffected. Although VDAs therapy is considered an important option for treatment, its use is still limited. The tumor cells at the periphery are less sensitive to vascular shutdown than those at the center, and subsequently avoid a nutrient-deprived environment. This phenomenon is referred to as tumor resistance to VDAs treatment. The viable periphery rim of tumor cells contributes to tumor regeneration, metastasis, and ongoing progression. However, there is no systematic review of the plausible mechanisms of repopulation of the viable tumor cells following VDAs therapy. The purpose of this review is to provide insights into mechanisms of tumor surviving small-molecule VDAs therapy, and the synergetic treatment to the remaining viable tumor cells at the periphery.

Assessement of angiogenesis reveals blood vessel heterogeneity in lung carcinoma

Despite advances in treatment, the prognosis for lung cancer patients remains poor. Angiogenesis appears to be a promising target for lung cancer therapy; however, the clinical significance of vascular changes are not completely understood. The aim of this study was to evaluate the types and morphology of blood vessels in various lung carcinomas. Using double immunostaining, we investigated 39 biopsies from patients admitted with various histological types of lung carcinoma. Tumor blood vessels were quantified separately for CD34/smooth muscle actin and described as either immature, intermediate or mature. Double immunostaining evaluation of the type of blood vessels in lung carcinomas revealed a marked heterogeneity. The immature and intermediate type of vessels were more common in adenocarcinomas (ADCs) and squamous cell carcinomas (SCCs) of the lung. Small cell lung carcinomas revealed a significant correlation between pathological and immature types of blood vessels. Therefore, quantifying the types of tumor vessels in lung carcinomas may be an important element to improve the results of anti-vascular therapy.

Morphometric study of microvessels in primary CNS tumors and its correlation with tumor types and grade

INTRODUCTION

Alterations of microvasculature are integral to CNS neoplasia, and a diagnostic feature of high-grade gliomas. The objectives of this study were two fold: First, to correlate morphometrically measured microvessel density (MVD), microvessel caliber (VC), and percentage of total microvessel area (%TVA) with WHO histologic grade in various types of primary CNS tumors. Second, to evaluate if such a correlation could be further refined by using mathematical derivatives of measured parameters namely coefficient of variation of VC (COofVC), microvessel cross-sectional area (VCSA), and percentage of total VCSA (%TVCSA).

MATERIALS AND METHODS

Various microvessel parameters were assessed in a variety of 30 primary CNS tumors as consecutively encountered in routine surgical pathology practice including gliomas, meningiomas and others by image morphometry using CD34-immunostained sections. We introduced a novel method of effectively determining VC. Results were correlated with tumor type and grade. Appropriate statistical analysis was performed.

RESULTS

Microvessel characteristics, especially VC (p<0.0022), VCSA (p<0.0164), CVofVC (p<0.0001), %TVCSA (p<0.0002) and %TVA (p<0.0003) of tumors were significantly greater than normal tissue. MVD increased in all tumors, excepting meningiomas, and was significantly higher in gliomas (p<0.0062). MVD showed negative correlation with VC (r=-0.808) and VCSA (r=-0.848) in the normal brain but was less significant in tumors. Unlike tumors, caliber distribution of microvessels in normal brain was noted to follow a Gaussian pattern. Histological grades of tumors showed positive correlation with MVD (r=0.547), VC (r=0.606), CVofVC (r=0.623), VCSA (r=0.485), %TVCSA (r=0.783) and %TVA (r=0.603). Calculated scores, estimated from multiple regressions of vessel parameters, correlated well with histological grade, with S2 (calculated using all measured as well as mathematically derived microvessel parameters) being better than S1 (calculated using measured parameters: MVD and VC).

CONCLUSION

Tumor grades positively correlated with all microvessel parameters, with %TVCSA displaying the best. The correlation of %TVA with tumor grade was weaker than %TVCSA mainly due to the impact of MVD. These findings emphasize the value of VC as effectively measured using our novel method and best illustrated by its derivative %TVCSA (an indicator of blood flow), in addition to the well-recognized value of MVD in tumor prognostication. Multiple regressions of microvessel parameters provided the best correlation with grade. Morphometric analysis of microvessels in CNS tumor facilitates a better understanding of the tumor grade, tumor progression and overall prognosis.