Determining circulating endothelial cells using CellSearch system during preoperative systemic chemotherapy in breast cancer patients

Evaluation of Circulating Endothelial Cells as Direct Marker of Endothelial Damage in Allo-Transplant Recipients at High Risk of Hepatic Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome

Sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD), is a rare but potentially fatal complication following allogenic hematopoietic cell transplantation (allo-HCT). Timely identification of SOS/VOD to allow for prompt treatment is critical, but identifying a VOD-predictive biomarker remains challenging. Given the pivotal role of endothelial dysfunction in SOS/VOD pathophysiology, the CECinVOD study prospectively evaluated levels of circulating endothelial cells (CECs) in patients undergoing allo-HCT with a myeloablative conditioning (MAC) regimen to investigate the potential of CEC level in predicting and diagnosing SOS/VOD. A total of 150 patients from 11 Italian bone marrow transplantation units were enrolled. All participants were age >18 years and received a MAC regimen, putting them at elevated risk of developing SOS/VOD. Overall, 6 cases of SOS/VOD (4%) were recorded. CECs were detected using the Food and Drug Administration-approved CellSearch system, an immunomagnetic selection-based platform incorporating ferrofluid nanoparticles and fluorescent-labeled antibodies, and were defined as CD146+, CD105+, DAPI+, or CD45-. Blood samples were collected at the following time points: before (T0) and at the end of conditioning treatment (T1), at neutrophil engraftment (T2), and at 7 to 10 days postengraftment (T3). For patients who developed VOD, additional samples were collected at any suspected or proven VOD onset (T4) and weekly during defibrotide treatment (T5 to T8). A baseline CEC count >17/mL was associated with an elevated risk of SOS/VOD (P = .04), along with bilirubin level >1.5 mg/mL and a haploidentical donor hematopoietic stem cell source. Postconditioning regimen (T1) CEC levels were elevated (P = .02), and levels were further increased at engraftment (P < .0001). Additionally, patients developing SOS/VOD after engraftment, especially those with late-onset SOS/VOD, showed a markedly higher relative increase (>150%) in CEC count. Multivariate analysis supported these findings, along with a high Endothelial Activation and Stress Index (EASIX) score at engraftment (T2). Finally, CEC kinetics corresponded with defibrotide treatment. After the start of therapy (T4), CEC levels showed an initial increase in the first week (T5), followed by a progressive decrease during VOD treatment (T6 and T7) and a return to pre-SOS/VOD onset levels at resolution of the complication. This prospective multicenter study reveals a low incidence of SOS/VOD in high-risk patients compared to historical data, in line with recent reports. The results from the CECinVOD study collectively confirm the endothelial injury in allo-HCT and its role in in the development of SOS/VOD, suggesting that CEC level can be a valuable biomarker for diagnosing SOS/VOD and identifying patients at greater risk of this complication, especially late-onset SOS/VOD. Furthermore, CEC kinetics may support treatment strategies by providing insight into the optimal timing for discontinuing defibrotide treatment.

Circulating Endothelial Cells are Associated with Thromboembolic Events in Patients with Antiphospholipid Antibodies

BACKGROUND

 Endothelial damage has been described in antiphospholipid antibody (aPL)-positive patients. However, it is uncertain whether circulating endothelial cells (CECs)-which are released when endothelial injury occurs-can be a marker of patients at high risk for thrombosis.

METHODS

 Ninety-seven patients with aPL and/or systemic lupus erythematosus (SLE) were included. CECs were determined by an automated CellSearch system. We also assayed plasma levels of tissue factor-bearing extracellular vesicles (TF⁺/EVs) and soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) as markers of endothelial dysfunction/damage.

RESULTS

 Patients' mean age was 46.1 ± 13.9 years, 77 were women. Thirty-seven had SLE and 75 patients were suffering from antiphospholipid syndrome. Thirty-seven percent of patients presented a medical history of arterial thrombosis and 46% a history of venous thromboembolism (VTE). Thirteen patients had increased levels of CECs (>20/mL), with a mean CEC level of 48.3 ± 21.3 per mL. In univariate analysis, patients with obesity or medical history of myocardial infarction (MI), VTE, or nephropathy had a significant increased CEC level. In multivariate analysis, obesity (odds ratio [OR] = 6.07, 95% confidence interval [CI]: 1.42-25.94), VTE (OR = 7.59 [95% CI: 1.38-41.66]), and MI (OR = 5.5 [95% CI: 1.1-26.6)] were independently and significantly associated with elevated CECs. We also identified significant correlations between CECs and other markers of endothelial dysfunction: sTREM-1 and TF⁺/EVs.

CONCLUSION

 This study demonstrated that endothelial injury assessed by the levels of CECs was associated with thromboembolic events in patients with aPL and/or autoimmune diseases.

Predictors of Neoadjuvant Chemotherapy Response in Breast Cancer: A Review

Neoadjuvant chemotherapy (NAC) largely increases operative chances and improves prognosis of the local advanced breast cancer patients. However, no specific means have been invented to predict the therapy responses of patients receiving NAC. Therefore, we focus on the alterations of tumor tissue-related microenvironments such as stromal tumor-infiltrating lymphocytes status, cyclin-dependent kinase expression, non-coding RNA transcription or other small molecular changes, in order to detect potentially predicted biomarkers which reflect the therapeutic efficacy of NAC in different subtypes of breast cancer. Further, possible mechanisms are also discussed to discover feasible treatment targets. Thus, these findings will be helpful to promote the prognosis of breast cancer patients who received NAC and summarized in this review.

Dynamic monitoring of CD45-/CD31+/DAPI+ circulating endothelial cells aneuploid for chromosome 8 during neoadjuvant chemotherapy in locally advanced breast cancer

Background:

Neoadjuvant chemotherapy (NCT) is the standard treatment for patients with locally advanced breast cancer (LABC). The aim of this study was to verify this relationship, and to estimate the clinical value of aneuploid circulating endothelial cells (CECs) in LABC patients with different NCT responses.

Methods:

Breast cancer patients received an EC4-T4 NCT regimen. Peripheral blood mononuclear cells were obtained before NCT, and after the first and last NCT courses. A novel subtraction enrichment and immunostaining fluorescence in situ hybridization (SE-iFISH) strategy was applied for detection of circulating rare cells (CRCs). CECs (CD45–/CD31+/DAPI+) and circulating tumor cells (CTCs) with different cytogenetic abnormalities related to chromosome 8 aneuploidy were analyzed in LABC patients subjected to NCT.

Results:

A total of 41 patients were enrolled. Firstly, CD31+/EpCAM+ aneuploid endothelial-epithelial fusion cells were observed in LABC patients. Further, aneuploid CECs in the peripheral blood showed a biphasic response during NCT, as they initially increased and then decreased, whereas a strong positive correlation was observed between aneuploid CECs and CTC numbers.

Conclusion:

We determined that aneuploid CEC dynamics vary in patients with different response to chemotherapy. Elucidating the potential cross-talk between CTCs and aneuploid CECs may help characterize the process associated with the development of chemotherapy resistance and metastasis.

The Blood Circulating Rare Cell Population. What is it and What is it Good For?

Blood contains a diverse cell population of low concentration hematopoietic as well as non-hematopoietic cells. The majority of such rare cells may be bone marrow-derived progenitor and stem cells. This paucity of circulating rare cells, in particular in the peripheral circulation, has led many to believe that bone marrow as well as other organ-related cell egress into the circulation is a response to pathological conditions. Little is known about this, though an increasing body of literature can be found suggesting commonness of certain rare cell types in the peripheral blood under physiological conditions. Thus, the isolation and detection of circulating rare cells appears to be merely a technological problem. Knowledge about rare cell types that may circulate the blood stream will help to advance the field of cell-based liquid biopsy by supporting inter-platform comparability, making use of biological correct cutoffs and “mining” new biomarkers and combinations thereof in clinical diagnosis and therapy. Therefore, this review intends to lay ground for a comprehensive analysis of the peripheral blood rare cell population given the necessity to target a broader range of cell types for improved biomarker performance in cell-based liquid biopsy.

Prognostic value of CEC count in HER2-negative metastatic breast cancer patients treated with bevacizumab and chemotherapy: a prospective validation study (UCBG COMET)

BACKGROUND

Proof of concept studies has reported that circulating endothelial cell (CEC) count may be associated with the outcome of HER2-negative metastatic breast cancer (mBC) patients treated by chemotherapy and the anti-VEGF antibody bevacizumab. We report the results obtained in an independent prospective validation cohort (COMET study, NCT01745757).

METHODS

The main baseline criteria were HER2-negative mBC, performance status 0-2 and no prior chemotherapy for metastatic disease. CECs were detected by CellSearch® from 4 ml of blood at baseline and after 4 weeks of weekly paclitaxel and bevacizumab therapy. CEC counts (considered both as a continuous variable and using the previously described 20 CEC/4 ml cutoff) were associated with clinical characteristics and progression-free survival (PFS).

RESULTS

CEC count was obtained in 251 patients at baseline and in 207 patients at 4 weeks. Median baseline CEC count was 22 CEC/4 ml (range 0-2231). Baseline CEC counts were associated with performance status (p = 0.02). No statistically significant change in CEC counts was observed between baseline and 4 weeks of therapy. High baseline CEC count was associated with shorter PFS in univariate and multivariate analyses (continuous: p < 0.001; dichotomized: HR 1.52, 95% CI [1.15-2.02], p = 0.004). CEC counts at 4 weeks had no prognostic impact.

CONCLUSION

This study confirms that CEC count may be associated with the outcome of mBC patients treated with chemotherapy and bevacizumab. However, discrepancies with previous reports in terms of both the timing of CEC count and the direction of the prognostic impact warrant further clinical investigation.

Predicting the response to neoadjuvant therapy for early-stage breast cancer: tumor-, blood-, and imaging-related biomarkers

Neoadjuvant therapy (NAT) has been used increasingly in patients with locally advanced or early-stage breast cancer. However, the accurate evaluation and prediction of response to NAT remain the great challenge. Biomarkers could prove useful to identify responders or nonresponders, or even to distinguish between early and delayed responses. These biomarkers could include markers from the tumor itself, such as versatile proteins, genes, and ribonucleic acids, various biological factors or peripheral blood cells, and clinical and pathological features. Possible predictive markers could also include multiple features from functional imaging, such as standard uptake values in positron emission tomography, apparent diffusion coefficient in magnetic resonance, or radiomics imaging biomarkers. In addition, cells that indirectly present the immune status of tumor cells and/or their host could also potentially be used as biomarkers, eg, tumor-infiltrating lymphocytes, tumor-associated macrophages, and myeloid-derived suppressor cells. Though numerous biomarkers have been widely investigated, only estrogen and/or progesterone receptors and human epidermal growth factor receptor have been proven to be reliable biomarkers to predict the response to NAT. They are the only biomarkers recommended in several international guidelines. The other aforementioned biomarkers warrant further validation studies. Some multigene profiling assays that are commercially available, eg, Oncotype DX and MammaPrint, should be used with caution when extrapolated to NAT settings. A panel of combined multilevel biomarkers might be able to predict the response to NAT more robustly than individual biomarkers. To establish such a panel and its prediction model, reliable methods and extensive clinical validation are warranted.

A multicenter phase II trial of neoadjuvant letrozole plus low-dose cyclophosphamide in postmenopausal patients with estrogen receptor-positive breast cancer (JBCRG-07): therapeutic efficacy and clinical implications of circulating endothelial cells

Neoadjuvant endocrine therapy has been reported to decrease tumor size, which leads to increased breast conservation rates. To improve the clinical response, metronomic chemotherapy with endocrine therapy is a promising strategy. A multicenter phase II single‐arm neoadjuvant trial with letrozole and cyclophosphamide was conducted. Eligibility criteria included postmenopausal status, T2–4 N0–1, and estrogen receptor‐positive breast carcinoma. Letrozole (2.5 mg) plus cyclophosphamide (50 mg) was given orally once a day for 24 weeks. The primary endpoint was the clinical response rate (CRR). To investigate anti‐angiogenic effects, circulating endothelial cells (CECs) were quantified using the CellSearch system. From October 2007 to March 2010, 41 patients were enrolled. The CRR was 67.5% (52.0–80.0%), which was above the prespecified threshold (65%). The conversion rate from total mastectomy to breast‐conserving surgery was 64% (18/28). Grade 3 or greater nonhematological toxicity was not reported. Clinical response was associated with improved disease‐free survival (DFS) (P = 0.020). The increase in CEC counts at 8 weeks was observed in nonresponders (P = 0.004) but not in responders. Patients with higher CEC counts at baseline or post‐treatment showed worse DFS than those with lower counts (P < 0.001 at baseline and = 0.014 post‐treatment). Multivariate analysis showed that post‐treatment CEC counts but not pretreatment counts were independently correlated with DFS (P = 0.046). In conclusion, neoadjuvant letrozole plus cyclophosphamide showed a good clinical response for postmenopausal patients with estrogen receptor‐positive breast cancer. CEC quantification is a promising tool for treatment monitoring and prognostic stratification for metronomic therapy following validation of our results in larger studies. Clinical trial registration number: UMIN000001331 Phase II study of neoadjuvant letrozole combined with low‐dose metronomic cyclophosphamide for postmenopausal women with endocrine‐responsive breast cancer (JBCRG‐07)

Prognostic value of circulating endothelial cells in metastatic colorectal cancer

BACKGROUND

There is urgent need for improved staging in patients with metastatic colorectal cancer (mCRC). In this study, we evaluated the prognostic value of circulating endothelial cells (CEC) in comparison with circulating tumor cells (CTC) in patients with mCRC amenable for potentially curative surgery.

METHODS

A total of 140 patients were enrolled prospectively. CTC and CEC were measured with the CellSearch System (Veridex, NJ, USA). Cut-off values were determined using ROC analyses. Prognostic factors were identified by Cox proportional hazards models.

RESULTS

ROC analyses revealed ≥ 21 CEC as cut-off levels for detection, which was present in 68 (49%). CEC detection was associated with female gender (p = 0.03) only, whereas CTC detection was associated with presence of the primary tumor (p = 0.007), metastasis size (p < 0.001), bilobar liver metastases (p = 0.02), CEA (p < 0.001) and CA 19-9 levels (p < 0.001). On multivariate analysis only CEC detection (HR 1.81; p = 0.03) and preoperative CA19-9 levels (HR 2.28, p = 0.005) were revealed as independent predictors of poor survival.

CONCLUSIONS

CEC are of stronger prognostic value than CTC. Further studies are required to validate these results and to evaluate CEC as predictive biomarker for systemic therapy alone as well as in combination with other markers such as CA19-9.

A phase I/II pharmacokinetics/pharmacodynamics study of irinotecan combined with S-1 for recurrent/metastatic breast cancer in patients with selected UGT1A1 genotypes (the JBCRG-M01 study)

S-1 and irinotecan combination is attractive for breast cancer refractory to anthracyclines and taxanes. Patients with advanced human epidermal growth factor receptor 2 (HER2)-negative breast cancer previously treated with anthracyclines and taxanes were eligible. Patients with brain metastases and homozygous for UGT1A1 *6 or *28 or compound heterozygous (*6/*28) were excluded. A dose-escalation design was chosen for the phase I portion (level 1: irinotecan 80 mg/m²  days 1-8 and S-1 80 mg/m²  days 1-14 every 3 weeks; level 2: irinotecan 100 mg/m² and S-1 80 mg/m² ). Study objectives included determination of the recommended dose for phase II, response rate, progression-free survival (PFS), and safety. Pharmacokinetics and CD34⁺ circulating endothelial cells (CECs) as pharmacodynamics were also analyzed. Thirty-seven patients were included. One patient at each level developed dose-limiting toxicities; therefore, level 2 was the recommended dose for phase II. Diarrhea was more common in patients possessing a *6 or *28 allele compared with wild-type homozygous patients (46% and 25%). Among 29 patients treated at level 2, PFS was longer for UGT1A1 wt/*6 and wt/*28 patients than for wt/wt patients (12 vs. 8 months, P = 0.06). PFS was significantly longer in patients with a larger-than-median SN-38 area under the curve (AUC) than in those with a smaller AUC (P = 0.039). There was an association between clinical benefit and reduction in baseline CD34⁺ CECs by S-1 (P = 0.047). The combination of irinotecan and S-1 is effective and warrants further investigation.

Circulating endothelial cells and their subsets: novel biomarkers for cancer

Angiogenesis contributes to the growth of solid tumors. Antiangiogenic agents are widely used in various cancers and considerable efforts have been made in the development of novel biomarkers that can predict the outcome of an anticancer treatment. Of those, circulating endothelial cells (CECs) and their subsets constitute a surrogate tool for monitoring disease activity. However, owing to the lack of standardization on the phenotypes and detection of CECs and their subsets, results have always been inconsistent and uninterpretable. In this review, we focus on the biological characteristics in terms of physiology, phenotypes and detection of CECs along with their subsets; review the current scenario of CEC enumeration as a surrogate biomarker in clinical oncology; and explore their future potential applications.

The lack of increases in circulating endothelial progenitor cell as a negative predictor for pathological response to neoadjuvant chemotherapy in breast cancer patients

Circulating endothelial progenitor cells are a potential surrogate marker for angiogenesis. Little is known about the alteration of circulating endothelial progenitor cell counts during neoadjuvant chemotherapy. Our goal was to reveal the alteration in CEP counts in association with response to neoadjuvant chemotherapy in patients with breast cancer. We measured the number of circulating endothelial progenitor cells (CD31⁺CD34⁺CD133⁺CD45^dim) by four-color flow cytometry using blood samples from 57 patients with breast cancer who received neoadjuvant chemotherapy (5-fluorouracil + epirubicin + cyclophosphamide (FEC), docetaxel + cyclophosphamide (TC), cisplatin + docetaxel (TP)). There was no significant difference in the baseline circulating endothelial progenitor cell counts with respect to the clinical and pathological background factors. Circulating endothelial progenitor cell counts increased after the initiation of chemotherapy (pre-1st vs. pre-2nd cycle, p = 0.0035; pre-1st vs. pre-4th cycle, p = 0.047). An increase of circulating endothelial progenitor cell counts from pre-1st to pre-2nd cycle was associated with pCR (p = 0.013 for χ² test). A multivariate analysis, including subtype, and clinical response showed that the lack of circulating endothelial progenitor cell increases from pre-1st to pre-2nd cycle was an independent negative predictor of pCR (p = 0.002). Our data suggest that alterations in circulating endothelial progenitor cell counts are associated with treatment response. The circulating endothelial progenitor cell count could be a useful biomarker for monitoring chemotherapeutic response.

Breast cancer patients do better after preoperative chemotherapy if their numbers of circulating endothelial progenitor cells (CEPs) go up. A team from Japan led by Takayuki Ueno from the Kyorin University School of Medicine in Tokyo studied 57 women who underwent neoadjuvant chemotherapy to shrink the size of their tumors before surgery. The researchers measured the number of CEPs—cells that derive from the bone marrow and can help build new blood vessels around tumors—both before and during chemotherapy. They found no link between overall CEP counts and treatment response. However, patients whose CEP numbers went up between cycles of chemotherapy had better outcomes. The authors suggest that CEP counts could be used as a diagnostic tool for predicting responses to neoadjuvant chemotherapy, although larger studies are needed to confirm their initial findings

Circulating endothelial cells and their progenitors in acute myeloid leukemia

Acute myeloid leukemia (AML) is an aggressive hematological malignancy characterized by the accumulation of immature myeloid progenitor cells in the bone marrow. Studies are required to investigate the prognostic and predictive value of surrogate biomarkers. Given the importance of angiogenesis in oncology in terms of pathogenesis as well as being a target for treatment, circulating endothelial cells (CECs) and endothelial progenitor cells (EPCs) are promising candidates to serve as such markers. The aim of the present study was to quantify CECs and EPCs in patients with AML at initial diagnosis and following induction chemotherapy, and to correlate these findings with the response to treatment in AML patients. The present study included 40 patients with de novo AML and 20 age- and gender-matched healthy controls. CECs and EPCs were evaluated by flow cytometry at initial diagnosis and after induction chemotherapy (3+7 protocol for AML other than M3 and all-trans-retinoic acid plus anthracycline for M3 disease). CECs and EPCs were significantly higher in AML patients at diagnosis and after induction chemotherapy than in controls. After induction chemotherapy, CECs and EPCs were significantly decreased compared with the levels at initial diagnosis. Patients who achieved complete response (n=28) had lower initial CEC and EPC levels compared with patients who did not respond to treatment. These results suggest that CEC levels are higher in AML patients and may correlate with disease status and treatment response. Further investigations are required to better determine the predictive value and implication of these cells in AML management.

Circulating endothelial cells and their subpopulations: role as predictive biomarkers in antiangiogenic therapy for colorectal cancer

Several anticancer therapies have been developed to block angiogenesis, a key mechanism in tumor growth and metastasis. The predominantly cytostatic action of these compounds makes an assessment of their clinical activities inadequate if based only on the reduction of the tumor dimensions, as this may not reflect their true biologic efficacy. Thus, it is crucial to identify biomarkers that permit the recognition of potentially responsive subjects and to spare toxicity in those who are unlikely to benefit from treatment. Circulating endothelial cells (CECs) have been recently indicated as potential surrogate biomarkers of angiogenesis in several types of cancer. The possibility of rapidly quantifying these cells represents a promising tool for monitoring the clinical outcome of tumors with the potential to assess response to various treatments. However, the identification and quantification of CECs is technically difficult and not well standardized. A variety of methods to detect CECs in patients with solid tumors have been used; these are based on different technical approaches, combinations of surface markers, sample handling, and staining protocols. With an expanding interest in the field of potential clinical applications for CECs in oncology, the development of standardized protocols for analysis is mandatory. The aim of this review was to critically summarize the available data concerning the clinical value of CECs and their subpopulations as biomarkers of antiangiogenic therapy in patients with metastatic colorectal cancer.

Are changes in circulating tumor cell (CTC) count associated with the response to neoadjuvant chemotherapy in local advanced breast cancer? A meta-analysis

INTRODUCTION

Circulating tumor cells (CTCs) represent a biomarker for tumor progression and monitoring therapeutic effects. We evaluated the association between the changes in CTC count and the pathological response to neoadjuvant chemotherapy (NCT) for local advanced breast cancer (LABC) patients.

METHODS

PubMed, EBSCO, Web of Science, conference proceedings and key trials for the period 1998-2012 were searched. We used the hazard ratio (HR) to evaluate the variation in the number of CTCs to predict the response to NCT in LABC patients. All data from each study were investigated using either fixed- or random-effect models and were analyzed using Stata software.

RESULTS

There was no between-study heterogeneity in pathological complete response (pCR) (heterogeneity chi-squared = 0.02 (df = 1), I(2) = 0.0%, p = 0.877). Our meta-analysis showed that the change (decrease or increase) in CTC number in LABC patients during NCT was not correlated with pCR (HR = 0.918, 95% confidence interval 0.650-1.295; p = 0.877).

CONCLUSION

The results of the current meta-analysis indicate that there is no association between the decrease of CTC number and pCR after NCT. According to our results, a decrease in the CTC count after NCT in LABC patients did not indicate that they had an improved response to NCT. However, more randomized clinical trials are needed to confirm this conclusion.

Neoadjuvant treatment of HER2 and hormone-receptor positive breast cancer - moving beyond pathological complete response

Pathologic complete response (pCR) was noted to be prognostic in all but hormone receptor-positive (HR) breast cancer cases even when HER2 is overexpressed. Evocative data suggest that HER2-positive breast cancer patients are a heterogeneous population and a subset of HER2-positive and HR-positive tumors biologically behave more like HER2-negative. Identification and targeted monitoring of these patients is crucial to consolidate data aiming to optimize combination treatment with new agents, thereby avoiding overtreatment with chemotherapy. The questions surrounding HER2-positive and HR-positive breast cancer patients treatment as well as the potential direction towards development of surrogate markers alternative to pCR are discussed.

Orally administered S-1 suppresses circulating endothelial cell counts in metastatic breast cancer patients

BACKGROUND

S-1 is an oral cytotoxic preparation that contains tegafur. Gamma-butyrolactone (GBL) is a metabolite of tegafur that is known to suppress vascular endothelial growth factor (VEGF)-mediated angiogenic activity. The aim of this study was to determine the change in circulating endothelial cell (CEC) counts, GBL levels, and angiogenesis-related factors during S-1 administration in metastatic breast cancer (MBC) patients.

METHODS

Patients with HER2-negative MBC were eligible. S-1 was administered orally twice daily in a 4 week on/2 week off cycle until disease progression or unacceptable toxicity occurred. Blood was collected on the following: days 1, 43, 85 (before each cycle of S-1 administration), days 15, 57 (1 h after S-1 administration), and day 29. The CellSearch(®) system was used to count the CECs. The gas chromatographic-mass spectrometric method was used to measure plasma GBL and 5-FU levels. Levels of VEGF were assayed by enzyme-linked immunosorbent assay.

RESULTS

A total of 18 patients were enrolled. The plasma GBL levels on days 15 and 57 were 41.3 ± 15.8 and 41.0 ± 11.2 ng/mL, respectively. The CEC levels decreased on day 15, and significantly low levels were maintained until day 85 (P = 0.002 vs day 1). The plasma VEGF levels significantly decreased on day 15 (P = 0.012 vs day 1) and had a tendency to decrease until day 57.

CONCLUSIONS

This exploratory study showed that GBL levels increased, VEGF levels decreased, and CEC levels were suppressed during S-1 administration. S-1 appears to have anti-angiogenic activity.

Expression of Ki67 and CD105 as proliferation and angiogenesis markers in salivary gland tumors

OBJECTIVE

To investigate the association between CD105 and tumor cell proliferation in salivary gland tumors.

METHODS

In this study, 59 samples of salivary tumors from Khalili Hospital archive, including 20 cases of pleomorphic adenoma (PA), 20 cases of mucoepidermoid carcinoma (MEC) and 19 cases of adenoid cystic carcinoma, as well as 10 cases of normal salivary gland tissue, were reviewed by immunohistochemistry (IHC) for CD105 and Ki67 staining.

RESULTS

CD105 positive vessels were absent in normal salivary gland tissue in the vicinity of tumors (51.6% of all tumors were positive). There was a statistically significant difference in frequency of CD105 staining between PA and malignant tumors and between four groups of different lesions (p<0.000) being highest in MEC. Intratumoral microvessel density was also elevated in malignant neoplasms (2.61 ± 3.1) as compared to PA (0.46 ± 0.6). Normal salivary glands did not express Ki67. There was a statistically significant difference in frequency and percentage of Ki67 immunoreactivity in malignant neoplasms (86.5% and 10.7 ± 10.8 respectively) compared to PA (50% and 0.78 ± 0.2) and among the four groups values were highest in MEC (p<0.000).

CONCLUSION

n this study, it was observed a higher rate of angiogenesis and cellular proliferation was noted in malignant tumors compared to benign tumors, but no correlation was observed between these two markers.

Circulating endothelial cells and tumor blood volume as predictors in lung cancer

The current criteria for evaluating antiangiogenic efficacy is insufficient as tumor shrinkage occurs after blood perfusion decreases. Tumor blood volume (BV) in computed tomography perfusion imaging and circulating endothelial cells (CEC) might predict the status of angiogenesis. The present study aimed to validate their representation as feasible predictors in non-small-cell lung carcinoma (NSCLC). A total of 74 patients was categorized randomly into two arms undergoing regimens of vinorelbine and cisplatin (Navelbine and platinum [NP]) with rh-endostatin or single NP. The response rate, perfusion imaging indexes and activated CEC (aCEC) during treatment were recorded. Progression-free survival (PFS) was determined through follow up. Correlations among the above indicators, response and PFS were analyzed: aCEC increased significantly in cases of progressive disease after single NP chemotherapy (P = 0.024). Tumor BV decreased significantly in cases with a clinical benefit in the combined arm (P = 0.026), whereas inverse correlations existed between ∆aCEC (post-therapeutic value minus the pre-therapeutic value) and PFS (P = 0.005) and between ∆BV and PFS (P = 0.044); a positive correlation existed between ∆aCEC and ∆BV. Therefore, both aCEC and tumor BV can serve as predictors, and detection of both indicators can help evaluate the chemo-antiangiogenic efficacy in NSCLC more accurately.

Circulating Tumor Cells and Extracellular Nucleic Acids in Breast Cancer

Circulating tumor cells (CTCs) are defined as tumor cells circulating in the peripheral blood of patients, shed from either the primary tumor or from its metastases. The detection of circulating tumor cells (CTCs) in the peripheral blood of breast cancer patients may account for the different steps in the biologic progression of the disease. The detection of microscopic disease in patients with breast cancer is imperative to prognosis and can predict the efficacy of targeted treatments. In general, there are two main methods for their detection. These are based on cytometric and nucleic acid manipulation. Both methods generally require an enrichment step to increase sensitivity of the assay. This step is based on either detection of specific surface markers using immuno-selection and/or on morphological features, such as cell size or density. We review the methods of detecting CTCs, their prognostic implications, and opportunities to exploit the properties of CTCs to develop personalized therapy.

Clinical value of circulating endothelial cell detection in oncology

Given the importance of tumor vasculature in tumor biology and as a target for treatment, there is an increasing need for biomarkers that reflect effects impacting tumor vasculature accurately. Circulating endothelial cells (CECs) increase in number as a result of vascular damage in cancer and several other diseases. CEC count constitutes a promising tool for monitoring disease activity with potential to assess prognosis and response to treatment. Here, we address the current state-of-the-art of CEC enumeration as a biomarker in clinical oncology. We focus on technical issues concerning CEC detection, review results from clinical studies and explore future potential applications.