Detection of survivin-expressing circulating cancer cells in the peripheral blood of patients with esophageal squamous cell carcinoma and its clinical significance

Survivin as a Therapeutic Target for the Treatment of Human Cancer

Survivin was initially identified as a member of the inhibitor apoptosis (IAP) protein family and has been shown to play a critical role in the regulation of apoptosis. More recent studies showed that survivin is a component of the chromosome passenger complex and acts as an essential mediator of mitotic progression. Other potential functions of survivin, such as mitochondrial function and autophagy, have also been proposed. Survivin has emerged as an attractive target for cancer therapy because its overexpression has been found in most human cancers and is frequently associated with chemotherapy resistance, recurrence, and poor survival rates in cancer patients. In this review, we discuss our current understanding of how survivin mediates various aspects of malignant transformation and drug resistance, as well as the efforts that have been made to develop therapeutics targeting survivin for the treatment of cancer.

Survival mechanisms of circulating tumor cells and their implications for cancer treatment

Metastasis remains the principal trigger for relapse and mortality across diverse cancer types. Circulating tumor cells (CTCs), which originate from the primary tumor or its metastatic sites, traverse the vascular system, serving as precursors in cancer recurrence and metastasis. Nevertheless, before CTCs can establish themselves in the distant parenchyma, they must overcome significant challenges present within the circulatory system, including hydrodynamic shear stress (HSS), oxidative damage, anoikis, and immune surveillance. Recently, there has been a growing body of compelling evidence suggesting that a specific subset of CTCs can persist within the bloodstream, but the precise mechanisms of their survival remain largely elusive. This review aims to present an outline of the survival challenges encountered by CTCs and to summarize the recent advancements in understanding the underlying survival mechanisms, suggesting their implications for cancer treatment.

Multigene Profiling of Circulating Tumor Cells in Esophageal Squamous Cell Carcinoma Identifies Prognostic Cancer Driver Genes Associated with Epithelial-Mesenchymal-Transition Progression and Chemoresistance

We investigated the clinical significance of CTCs in cancer progression by detecting multiple cancer driver genes associated with epithelial-to-mesenchymal transition (EMT) at the transcript level. The 10-gene panel, comprising CCND1, ECT2, EpCAM, FSCN1, KRT5, KRT18, MET, TFRC, TWIST1, and VEGFC, was established for characterizing CTCs from mouse ESCC xenograft models and clinical ESCC peripheral blood (PB) samples. Correlations between gene expression in CTCs from PB samples (n = 77) and clinicopathological features in ESCC patients (n = 55) were examined. The presence of CTCs at baseline was significantly correlated with tumor size (p = 0.031). The CTC-high patients were significantly correlated with advanced cancer stages (p = 0.013) and distant metastasis (p = 0.029). High mRNA levels of TWIST1 (Hazard Ratio (HR) = 5.44, p = 0.007), VEGFC (HR = 6.67, p < 0.001), TFRC (HR = 2.63, p = 0.034), and EpCAM (HR = 2.53, p = 0.041) at baseline were significantly associated with a shorter overall survival (OS) in ESCC patients. This study also revealed that TWIST1 facilitates EMT and enhances malignant potential by promoting tumor migration, invasion, and cisplatin chemoresistance through the TWIST1-TGFBI-ZEB1 axis in ESCC, highlighting the prognostic and therapeutic potential of TWIST1 in clinical ESCC treatment.

Molecular Similarities and Differences between Canine Prostate Cancer and Human Prostate Cancer Variants

Dogs are one of few species that naturally develop prostate cancer (PCa), which clinically resembles aggressive, advanced PCa in humans. Moreover, PCa-tumor samples from dogs are often androgen receptor (AR)-negative and may enrich our understanding of AR-indifferent PCa in humans, a highly lethal subset of PCa for which few treatment modalities are available This narrative review discusses the molecular similarities between dog PCa and specific human-PCa variants, underscoring the possibilities of using the dog as a novel pre-clinical animal model for human PCa, resulting in new therapies and diagnostics that may benefit both species.

Circulating Tumor Cell Enumeration for Serial Monitoring of Treatment Outcomes for Locally Advanced Esophageal Squamous Cell Carcinoma

We aim to reveal the clinical significance and potential usefulness of dynamic monitoring of CTCs to track therapeutic responses and improve survival for advanced ESCC patients. Peripheral blood (PB) (n = 389) and azygos vein blood (AVB) (n = 13) samplings were recruited prospectively from 88 ESCC patients undergoing curative surgery from 2017 to 2022. Longitudinal CTC enumeration was performed with epithelial (EpCAM/pan-cytokeratins/MUC1) and mesenchymal (vimentin) markers at 12 serial timepoints at any of the pre-treatment, all of the post-treatments/pre-surgery, post-surgery follow-ups for 3-year, and relapse. Longitudinal real-time CTC analysis in PB and AVB suggests more CTCs are released early at pre-surgery and 3-month post-surgery into the circulation from the CTRT group compared to the up-front surgery group. High CTC levels at pre-treatments, 1-/3-month post-surgery, unfavorable changes of CTC levels between all post-treatment/pre-surgery and 1-month or 3-month post-surgery (Hazard Ratio (HR) = 6.662, p < 0.001), were independent prognosticators for curative treatment. The unfavorable pre-surgery CTC status was independent prognostic and predictive for neoadjuvant treatment efficacy (HR = 3.652, p = 0.035). The aggressive CTC clusters were more frequently observed in AVB compared to PB. Its role as an independent prognosticator with relapse was first reported in ESCC (HR = 2.539, p = 0.068). CTC clusters and longitudinal CTC monitoring provide useful prognostic information and potential predictive biomarkers to help guide clinicians in improving disease management.

Meta-analysis of the prognostic value of circulating tumor cells in gastrointestinal cancer

BACKGROUND

Detecting circulating tumor cells (CTCs) has become a new strategy for predicting the prognosis of cancer patients. However, limited systematic research evidence is available for the detection of CTCs in various gastrointestinal tumors such as esophageal cancer (EC), colorectal cancer (CRC) and gastric cancer (GC). This topic was addressed to assess the prognostic significance of CTCs in gastrointestinal tumors.

METHODS

We conducted a literature search according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist (from November 20, 2021). We performed a meta-analysis using the random effects model and Review Manager 5.3 software (The Cochrane Collaboration, Copenhagen, Denmark) according to the inclusion and exclusion criteria, data extraction and evaluation methods.

RESULTS

Twenty-four articles met the inclusion criteria for this study, and they included 3803 EC, CRC and GC patients, including 1189 CTC-positive and 2462 CTC-negative cases. The meta-analysis showed that the presence of CTCs was associated with worse OS (HR = 2.05, 95% CI = 1.75-2.40, P = .060) and PFS (HR = 2.27, 95% CI = 1.79-2.89, P < .001). Further meta-regression and subgroup analyses showed that CTC-positive patients also showed worse OS and PFS in different subgroups.

CONCLUSION

Our meta-analysis suggests that detecting CTCs in peripheral blood may be an important tool for improving the prognosis of patients with gastrointestinal tumors. Moreover, CTCs detection results could be used to develop personalized treatment plans in the future.

Squamous Cell Carcinoma of the Esophagus

Esophageal squamous cell carcinoma (ESCC) is common in the developing world with decreasing incidence in developed countries and carries significant morbidity and mortality. Major risk factors for ESCC development include significant use of alcohol and tobacco. Screening for ESCC can be recommended in high-risk populations living in highly endemic regions. The treatment of ESCC ranges from endoscopic resection therapy or surgery in localized disease to chemoradiotherapy in metastatic disease, and prognosis is directly related to the stage at diagnosis. New immunotherapies and molecular targeted therapies may improve the dismal survival outcomes in patients with metastatic ESCC.

Circulating tumor cells detected in follow-up predict survival outcomes in tri-modality management of advanced non-metastatic esophageal cancer: a secondary analysis of the QUINTETT randomized trial

Background

Our aim was to establish if presence of circulating tumor cells (CTCs) predicted worse outcome in patients with non-metastatic esophageal cancer undergoing tri-modality therapy.

Methods

We prospectively collected CTC data from patients with operable non-metastatic esophageal cancer from April 2009 to November 2016 enrolled in our QUINTETT esophageal cancer randomized trial (NCT00907543). Patients were randomized to receive either neoadjuvant cisplatin and 5-fluorouracil (5-FU) plus radiotherapy followed by surgical resection (Neoadjuvant) or adjuvant cisplatin, 5-FU, and epirubicin chemotherapy with concurrent extended volume radiotherapy following surgical resection (Adjuvant). CTCs were identified with the CellSearch® system before the initiation of any treatment (surgery or chemoradiotherapy) as well as at 6-, 12-, and 24-months post-treatment. The threshold for CTC positivity was one and the findings were correlated with patient prognosis.

Results

CTC data were available for 74 of 96 patients and identified in 27 patients (36.5%) at a median follow-up of 13.1months (interquartile range:6.8-24.1 months). Detection of CTCs at any follow-up visit was significantly predictive of worse disease-free survival (DFS;hazard ratio [HR]: 2.44; 95% confidence interval [CI]: 1.41-4.24; p=0.002), regional control (HR: 6.18; 95% CI: 1.18-32.35; p=0.031), distant control (HR: 2.93; 95% CI: 1.52-5.65;p=0.001) and overall survival (OS;HR: 2.02; 95% CI: 1.16-3.51; p=0.013). After adjusting for receiving neoadjuvant vs. adjuvant chemoradiotherapy, the presence of CTCs at any follow-up visit remained significantly predictive of worse OS ([HR]:2.02;95% [Cl]:1.16-3.51; p=0.013) and DFS (HR: 2.49;95% Cl: 1.43-4.33; p=0.001). Similarly, any observed increase in CTCs was significantly predictive of worse OS (HR: 3.14; 95% CI: 1.56-6.34; p=0.001) and DFS (HR: 3.34; 95% CI: 1.67-6.69; p<0.001).

Conclusion

The presence of CTCs in patients during follow-up after tri-modality therapy was associated with significantly poorer DFS and OS regardless of timing of chemoradiotherapy.

Liquid Biopsy in Squamous Cell Carcinoma of the Esophagus and of the Head and Neck

Squamous cell carcinomas of the esophagus (ESCC) and of the head and neck (HNSCC) are two neoplasms that share common risk factors and have the same embryological origin, but a very different prognosis, the 5-year survival of HNSCC being almost double (40–50%) compared to the 5-year survival of ESCC (20%). Current guidelines emphasize the importance of screening for ESCC in patients diagnosed with head and neck cancers. A liquid biopsy is a novel tool for diagnosis, prognostic stratification, and personalized therapy. Liquid biopsy biomarkers for these two malignancies could help both their early detection, facilitate residual disease identification, and provide prognosis information. The present systematic review of the literature was aimed at describing the liquid biopsy biomarkers present in these two malignancies, with an emphasis on potential clinical applications.

Circulating Tumor Cells in Esophageal Squamous Cell Carcinoma - Mini Review

Esophageal cancer has high incidence and mortality rates and a low five-year survival rate of <15% owing to its strong capabilities of invasion, relapse and metastasis. The classic view holds that metastasis and diffusion is an advanced event during cancer progression, but recent studies show that distant diffusion of primary cancer cells may actually be an early event. Detection of circulating tumor cells (CTCs) in the circulation may indicate tumor spread, so CTCs are considered to be the key factor of metastatic cascade. In recent years, despite research progress on CTCs, there is a lack of systematic and important evidence to confirm the diagnostic, monitoring and prognostic values of CTCs in esophageal squamous cell carcinoma (ESCC). In this review, we clarify the relationship between CTC values and ESCC and provide more reliable evidence to improve the management and treatment of ESCC.

Emerging Importance of Survivin in Stem Cells and Cancer: the Development of New Cancer Therapeutics

Survivin is one of the rare proteins that is differentially expressed in normal and cancer cells and is directly or indirectly involved in numerous pathways required for tumor maintenance. It is expressed in almost all cancers and its expression has been detected at early stages of cancer. These traits make survivin an exceptionally attractive target for cancer therapeutics. Even with these promising features to be an oncotherapeutic target, there has been limited success in the clinical trials targeting survivin. Only recently it has emerged that survivin was not being specifically targeted which could have resulted in the negative clinical outcome. Also, focus of research has now shifted from survivin expression in the overall heterogeneous tumor cell populations to survivin expression in cancer stem cells as these cells have proved to be the major drivers of tumors. Therefore, in this review we have analyzed the expression of survivin in normal and cancer cells with a particular focus on its expression in cancer stem cell compartment. We have discussed the major signaling pathways involved in regulation of survivin. We have explored the current development status of various types of interventions for inhibition of survivin. Furthermore, we have discussed the challenges involving the development of potent and specific survivin inhibitors for cancer therapeutics. Finally we have given insights for some of the promising future anticancer treatments.

The Diagnostic and Prognostic Value of a Liquid Biopsy for Esophageal Cancer: A Systematic Review and Meta-Analysis

Simple Summary

The “liquid biopsy” is a novel concept for detecting circulating biomarkers in the peripheral blood of patients with various cancers, including esophageal cancer. There are two main methods to identify circulating cancer related biomarkers such as morphological techniques or molecular biological techniques. There are some differences in the sensitivity and specificity for detecting circulating tumor cells (CTCs) or circulating markers between each method. Although it is still challenging to determine strong candidates for early diagnosis and predicting prognosis in patients with esophageal cancer, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.

Abstract

Esophageal cancer is among the most aggressive diseases, and circulating tumor cells (CTCs) have been recognized as novel biomarkers for various cancers over the past two decades, including esophageal cancer. CTCs might provide crucial clinical information for predicting cancer prognosis, monitoring therapeutic responses or recurrences, or elucidating the mechanism of metastasis. The isolation of CTCs is among the applications of a “liquid biopsy”. There are various technologies for liquid biopsies, and they are classified into two main methods: cytometric or non-cytometric techniques. Here, we review a total of 57 eligible articles to summarize various technologies for the use of a liquid biopsy in esophageal cancer and perform a meta-analysis to assess the clinical utility of liquid biopsies as a prognostic and diagnostic biomarker technique. For prognostic evaluation, the pooled hazard ratio in the cytometric assay is relatively higher than that of the non-cytometric assay. On the other hand, a combination of multiple molecules, using a non-cytometric assay, might be a favorable biomarker technique for the early diagnosis of esophageal cancer. Although determining strong evidence for a biomarker by using a liquid biopsy is still challenging, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.

Karyotyping of circulating tumor cells for predicting chemotherapeutic sensitivity and efficacy in patients with esophageal cancer

Background

Aneuploidy of chromosome 8 in circulating tumor cells (CTCs) has been reported correlates with therapeutic efficacy and prognosis in patients with advanced gastric cancer. However, it is not clear whether it is also appropriate for other cancer. Therefore, in this study, we evaluate the clinical application aneuploidy of CTCs for esophageal cancer.

Methods

Peripheral blood were collected for karyotyping analysis before and after first 4-cycles chemotherapy from seventy nine patients with newly diagnosed esophageal cancer. Karyotyping of chromosome 8 in CTCs detected by SET-iFISH (Subtraction Enrichment-Immunostaining fluorescence in situ hybridizatio) in those patients were grouped into two categories according to CTC number: triploid group and non-triploid group. Pearson Chi-Square were used to compare the association between different aneuploidy type and chemotherapeutic sensitivity and efficacy.

Results

Among the 16 patients with triploid of chromosome 8, 4 patients benefit, and of the 63 patients with non-triploid, 54 patients benefit. Chi-square test analysis found that clinical benefit of non-triploid patients was significantly higher than triploid patients, suggesting non-triploid patients were more sensitive to chemotherapy than triploid patients. After 4-cycles chemotherapy, it is found that chemotherapeutic efficacy was positively correlated with non-triploid proportion. These results suggest that non-triploid proportion could be used as a candidate maker for assessing chemotherapeutic efficacy.

Conclusions

Monitoring aneuploidy of chromosome 8 in CTCs before and after chemotherapy may help predict sensitivity and efficacy of chemotherapy in patients with esophageal cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5850-7) contains supplementary material, which is available to authorized users.

Clinicopathological and prognostic significance of circulating tumor cells in patients with esophageal cancer: a meta-analysis

Background

The aim of this meta-analysis was to assess the clinicopathological and prognostic significance of circulating tumor cells (CTCs) in patients with esophageal cancer (EC).

Methods

We searched PubMed, EMBASE, Science Citation Index Expanded, Cochrane library (from inception to July 2018) with the keywords “esophageal cancer”, “circulating tumor cells”, “prognosis”, and “peripheral blood”. HR, risk ratio (RR), OR, and their 95% CIs were set as effect measures. All analyses were performed by STATA 12.0.

Results

Eighteen studies were retrieved; CTC-positive patients were significantly associated with poor progression-free survival (PFS) (HR=2.61; 95% CI=2.08–3.28) and overall survival (OS) (HR=2.50; 95% CI=2.12–2.94). CTC-positive patients were also associated with high recurrence (OR=2.84; 95% CI=1.81–4.44) and poor response of chemoradiotherapy (RR=0.64; 95% CI=0.43–0.96). For clinicopathological characteristics, CTC-positive patients were significantly associated with TNM staging, depth of infiltration, regional lymph nodes metastasis, distant metastasis, lymphatic invasion, and venous invasion.

Conclusion

The meta-analysis has confirmed the significant clinicopathological and prognostic value of CTC-positive patients for both PFS and OS in patients with EC.

Survival Mechanisms and Influence Factors of Circulating Tumor Cells

Circulating tumor cells (CTCs) are cancer cells shed from either the primary tumor or its metastases that circulate in the peripheral blood. The CTCs are regarded as the source of tumor recurrence and metastasis and speculated as the indicators of residual tumors, thereby indicating a poor prognosis. Although CTCs play a vital role in tumor metastasis and recurrence, little is known about the underlying survival mechanisms in the blood circulation. The accumulating evidence has revealed that CTCs might survive in the peripheral blood by overcoming the mechanical damage due to shear stress, resistance to anoikis, evasion of immune destruction, and resistance to chemotherapy. The present review addresses the putative survival mechanisms underlying the formation and migration of CTCs according to their biological characteristics and blood microenvironment. In addition, the relationship between CTCs and microenvironment is illustrated, and the influencing factors related to the interactions of CTCs with various components in the peripheral blood are reviewed with respect to the platelets, immune cells, cytokines, and circulating tumor microemboli (CTM). Furthermore, the recent advances in the new treatment strategies targeting the survival mechanisms of CTCs are also discussed.

Clinical significance of plasma anti-TOPO48 autoantibody and blood survivin-expressing circulating cancer cells in patients with early stage endometrial carcinoma

PURPOSE

To examine the clinical significance of an autoantibody (AAb) against a novel tumor-associated antigen (TAA) derived from human DNA-topoisomerase I, termed as TOPO48 AAb, and peripheral blood survivin-expressing circulating cells (CCC) in patients with early stage endometrial cancer (EC).

METHODS

Blood samples were collected from 80 patients with early stage EC and 80 age-matched healthy subjects. Plasma levels of the TOPO48 AAb were measured with a specific antibody capture enzyme-linked immunosorbent assay (ELISA) and blood survivin-expressing CCC assessed with a reverse transcription-polymerase chain reaction products based on a hybridization-enzyme-linked immunosorbent assay (RT-PCR-ELISA). Sixty patients were followed up for 36 months after the initial assay test.

RESULTS

There were 75% and 60% samples with positive levels of the TOPO48 AAb and survivin-expressing CCC in the cancer patients, respectively. However, the cumulative positive rate of combination of the two markers was increased to 93.3% with 0.927 (95% CI 0.871-0.984) of area under the curve (AUC) in receiver operating characteristic (ROC) curve analysis. During the follow-up period, patients with positive TOPO48 AAb but negative surviving-expressing CCC had a higher survival rate and a longer survival time than those with negative AAb but positive CCC (P = 0.01).

CONCLUSIONS

The combination of TOPO48 AAb and survivin-expressing CCC may be used as a novel recipe to improve the efficiency of early diagnosis and provide more accurate prognostic prediction in patients with early stage EC.

Screening for esophageal squamous cell carcinoma: recent advances

Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer worldwide, with a high mortality due to advanced stage at diagnosis. Although most common in an area known as the Asian Esophageal Cancer Belt, which extends from the Caspian Sea to northern China, and in parts of Africa, high-risk populations also exist elsewhere in the world. Screening for ESCC has been practiced in a few geographic areas and high-risk populations, with varying levels of success. Esophageal squamous dysplasia is recognized as the precursor lesion for ESCC. Endoscopic screening for ESCC/esophageal squamous dysplasia is expensive and not sufficiently available in many high-risk regions. Recent advances in non-endoscopic screening enhanced by biomarker-based disease detection have raised the prospect of improved accuracy and availability of screening for esophageal squamous dysplasia and early stage ESCC. Development of a cost-effective, accurate, and well-tolerated screening test, if applied in endemic areas and high-risk populations, has the potential to reduce mortality from this deadly disease worldwide. In this review, we summarize recent developments in endoscopic and non-endoscopic screening modalities.

Research progress and prospects of esophageal cancer in era of precision medicine

Esophageal cancer (EC) is a common digestive system carcinoma, and China has the highest incidence of EC in the world. The prognosis of EC is poor; the five-year survival rate of EC in developing countries is extremely low because the clinical symptoms are often found too late, which makes the patients cannot be cured. In the era of precision medicine, new concepts and technologies are applied to the screening, diagnosis, and treatment of EC. Therefore, it becomes possible to formulate a personalized and accurate disease prevention and treatment program for each patient, so as to achieve maximum therapeutic effect, minimize side effects, and ultimately achieve the goal of improving the prognosis of EC. This article reviews the recent research progress and prospects of EC in the era of precision medicine with regard to disease screening, diagnosis, and treatment.

Significant prognostic value of circulating tumor cells in esophageal cancer patients: A meta-analysis

Esophageal cancer is the sixth leading cause of cancer death worldwide. Detection of circulating tumor cells (CTCs) is emerging as a novel strategy for predicting cancer patient prognosis. Here we performed a comprehensive literature search to identify relevant articles in EMbase, PubMed, EBSCO, OVID, Cochrane Database, CNKI, WanFangdata and VIPdata. Meta-analysis was conducted using Stata12.0 software, according to the inclusion and exclusion criteria, extracted data and assessment methodology. Thirteen eligible literature studies were included with a total of 979 esophageal squamous cell carcinoma patients, including 424 CTC-positive and 684 CTC-negative cases. Meta-analysis showed that the presence of CTCs was associated with both worse progression-free/disease-free survival [hazard ration (HR) = 2.32, 95% confidence interval (CI) = 1.57 - 3.43, p < 0.001] and poorer overall survival [HR = 2.64, 95% CI = 1.69 - 4.14, p < 0.001]. Further subgroup analyses demonstrated that CTC-positive patients also showed worse progression-free/disease-free survival and poorer overall survival in different subsets. In summary, our meta-analysis provides strong evidence that detection of CTCs in the peripheral blood is an independent prognostic indicator of poor outcome for esophageal squamous cell carcinoma patients.

Combination of c-reactive protein and squamous cell carcinoma antigen in predicting postoperative prognosis for patients with squamous cell carcinoma of the esophagus

Background

We initially proposed a useful and novel prognostic model, named CCS [Combination of c-reactive protein (CRP) and squamous cell carcinoma antigen (SCC)], for predicting the postoperative survival in patients with esophageal squamous cell carcinoma (ESCC).

Methods

Two hundred and fifty-two patients with resectable ESCC were included in this retrospective study. A logistic regression was performed and yielded a logistic equation. The CCS was calculated by the combined CRP and SCC. The optimal cut-off value for CCS was evaluated by X-tile program. Univariate and multivariate analyses were used to evaluate the predictive factors. In addition, a novel nomogram model was also performed to predict the prognosis for patients with ESCC.

Results

In the current study, CCS was calculated as CRP+6.33 SCC according to the logistic equation. The optimal cut-off value was 15.8 for CCS according to the X-tile program. Kaplan-Meier analyses demonstrated that high CCS group had a significantly poor 5-year cancer-specific survival (CSS) than low CCS group (10.3% vs. 47.3%, P <0.001). According to multivariate analyses, CCS (P =0.004), but not CRP (P =0.466) or SCC (P =0.926), was an independent prognostic factor. A nomogram could be more accuracy for CSS (Harrell's c-index: 0.70).

Conclusion

The CCS is a usefull and independent predictive factor in patients with ESCC.

Prognostic value of circulating tumor cells in esophageal cancer

AIM

To perform a meta-analysis of the related studies to assess whether circulating tumor cells (CTCs) can be used as a prognostic marker of esophageal cancer.

METHODS

PubMed, Embase, Cochrane Library and references in relevant studies were searched to assess the prognostic relevance of CTCs in patients with esophageal cancer. The primary outcome assessed was overall survival (OS). The meta-analysis was performed using the random effects model, with hazard ratio (HR), risk ratio (RR) and 95% confidence intervals (95%CIs) as effect measures.

RESULTS

Nine eligible studies were included involving a total of 911 esophageal cancer patients. Overall analyses revealed that CTCs-positivity predicted disease progression (HR = 2.77, 95%CI: 1.75-4.40, P < 0.0001) and reduced OS (HR = 2.67, 95%CI: 1.99-3.58, P < 0.00001). Further subgroup analyses demonstrated that CTCs-positive patients also had poor OS in different subsets. Moreover, CTCs-positivity was also significantly associated with TNM stage (RR = 1.48, 95%CI: 1.07-2.06, P = 0.02) and T stage (RR = 1.44, 95%CI: 1.13-1.84, P = 0.003) in esophageal cancer.

CONCLUSION

Detection of CTCs at baseline indicates poor prognosis in patients with esophageal cancer. However, this finding relies on data from observational studies and is potentially subject to selection bias. Prospective trials are warranted.

Delivery of a survivin promoter-driven antisense survivin-expressing plasmid DNA as a cancer therapeutic: a proof-of-concept study

Survivin is a member of the inhibitor-of-apoptosis proteins family. It is overexpressed in many different cancer types but not in the differentiated normal tissue. In addition, overexpression of survivin promotes cancer cell survival and induces chemotherapeutic drug resistance, making it an attractive target for new anticancer interventions. Despite survivin being a promising molecular target for anticancer treatment, it is widely accepted that survivin is only a "semi-druggable" target. Therefore, it is important to develop a new strategy to target survivin for anticancer treatment. In this study, we constructed a novel survivin promoter-driven full-length antisense survivin (pSur/AS-Sur) expression plasmid DNA. Promoter activity assay revealed that the activity of the survivin promoter of pSur/AS-Sur correlated with the endogenous expression of survivin at the transcriptional level in the transfected A549, MDA-MB-231, and PANC-1 cancer cells. Western blot analysis showed that liposomal delivery of pSur/AS-Sur successfully downregulated the expression of survivin in A549, MBA-MB-231, and PANC-1 cells in vitro. In addition, delivery of pSur/AS-Sur induced autophagy, caspase-dependent apoptosis, and caspase-independent apoptosis as indicated by the increased LC3B-II conversion, autophagosome formation, caspase-9/-3 and poly(ADP-ribose) polymerase-1 cleavage, and apoptosis-inducing factor nuclear translocation in A549, MBA-MB-231, and PANC-1 cells. Importantly, liposomal delivery of pSur/AS-Sur was also capable of decreasing the proliferation of the survivin/MDR1 coexpressing multidrug-resistant KB-TAX50 cancer cells and the estrogen receptor-positive tamoxifen-resistant MCF7-TamC3 cancer cells in vitro. In conclusion, the results of this study suggest that delivery of a survivin promoter-driven antisense survivin-expressing plasmid DNA is a promising way to target survivin and to treat survivin-expressing cancers in the future.

Prognostic significance of circulating tumor cells in esophageal carcinoma: a meta-analysis

PURPOSE

The prognostic significance of circulating tumor cells (CTCs) in esophageal carcinoma (EC) is controversial. We aim to assess its association with clinicopathological and prognostic relevance in EC by using a meta-analysis.

METHODS

We searched PubMed, Cochrane Database, Embase databases, and the references in relevant studies that assessed the clinicopathological or prognostic relevance of CTCs in peripheral blood of patients with EC. Statistical analyses were conducted by using Stata software to calculate the pooled odds ratio (OR), hazard ratio (HR), and 95% confidence intervals (CIs) using fixed or random-effects models according to the heterogeneity of included studies. The subgroup analyses were performed according to ethnicity, histological type, and detection method.

RESULTS

Sixteen trials containing 1,260 patients were included for analysis. Pooled results showed that presence of CTCs was significantly associated with poor overall survival (HR =1.71, 95% CI [1.30, 2.12], P<0.001) and progression-free survival (HR =1.67, 95% CI [1.19, 2.15], P<0.001) in EC patients. Subgroup analysis indicated that presence of CTCs was closely associated with worse overall survival (Asian: HR =1.66, 95% CI [1.24, 2.08], P<0.001; squamous cell carcinoma [SCC]: HR =1.66, 95% CI [1.24, 2.08], P<0.001; no polymerase chain reaction [PCR]: HR =2.08, 95% CI [1.40, 2.76], P<0.001) and progression-free survival (Asian: HR =1.63, 95% CI [1.15, 2.12], P<0.001; SCC: HR =1.63, 95% CI [1.15, 2.12], P<0.001; PCR: HR =1.63, 95% CI [1.15, 2.12], P<0.001). Additionally, ORs showed that presence of CTCs was significantly correlated with tumor node metastasis (TNM) staging (overall: OR = 1.96, 95% CI [1.34, 2.87], P=0.001; Asian: OR =2.09, 95% CI [1.37, 3.19], P=0.001; SCC: OR =1.97, 95% CI [1.21, 3.07], P=0.003; PCR: OR =2.23, 95% CI [1.43, 3.47], P<0.001), venous invasion (overall: OR =2.23, 95% CI [1.46, 3.40], P<0.001; Asian: OR =2.23, 95% CI [1.46, 3.40], P<0.001; SCC: OR =2.23, 95% CI [1.46, 3.40], P<0.001; PCR: OR =2.23, 95% CI [1.46, 3.40], P<0.001), lymph node metastasis (overall: OR =2.41, 95% CI [1.50, 3.86], P<0.001; Asian: OR =2.89, 95% CI [1.80, 4.65], P<0.001; SCC: OR =2.44, 95% CI [1.47, 4.07], P=0.001; PCR: OR =2.89, 95% CI [1.80, 4.65], P<0.001) and distant metastasis (Asian: OR =2.68, 95% CI [1.01, 7.08], P=0.047) in patients with EC.

CONCLUSION

The presence of CTCs indicates a poor prognosis in EC patients, especially in Asian and SCC patients. Further well-designed prospective studies are recommended to explore the clinical applications of CTCs in patients with EC.

[Prognostic value of circulating tumor cells and disseminated tumor cells in patients with esophageal cancer: a meta-analysis]

OBJECTIVE

To explore the correlations of circulating tumor cells (CTCs) and disseminated tumor cells (DTCs) with the clinicopathological characteristics, prognostic events, and survival outcomes in esophageal cancer (EC) patients.

METHODS

The PubMed, Web of Science, Embase database and Cochrane database were searched for studies reporting the outcomes of interest. The studies were selected according to established inclusion/exclusion criteria. Meta-analysis of the studies was performed using Review Manager 5.3 and Stata12.0 software with the odds ratio (OR), risk ratio (RR) , hazard ratio (HR) , and 95% confidence interval (95% CI) as the effect indexes.

RESULTS

Nineteen studies involving a total of 1766 patients were included in the analysis. Significant correlations of CTCs and DTCs were found with the clinicopathological parameters including the tumor stage (OR=1.95), depth of invasion (OR=1.99), lymph node metastasis (OR=2.44_SEN), distal metastasis (OR=5.98_SEN), histological differentiation (OR=1.67) and lymphovascular invasion (OR=4.48). CTCs and DTCs were also correlated with the prognostic events including relapse (RR=6.86_SEN) and metastasis (RR=3.22) and with the survival outcomes including the overall survival (OS) overall analysis (HR=3.46) and disease-free survival/progression-free survival (DFS/PFS) overall analysis (HR=3.00).

CONCLUSION

CTCs and DTCs are significantly associated with an advanced tumor stage, depth of tumor invasion, lymph node metastasis, distant metastasis before therapy, differentiation, lymphovascular invasion, relapse and metastasis in patients with EC. They are also significantly correlated with a poorer survival for OS and DFS/PFS to serve as clinical and prognostic predictors in patients with EC.

Survivin activates NF‑κB p65 via the IKKβ promoter in esophageal squamous cell carcinoma

Survivin and transcription factor p65 (NF‑κB p65) participate in the progression of esophageal squamous cell carcinoma (ESCC). However, the mechanism of NF‑κB p65 activation in ESCC remains to be elucidated. The aim of the present study was to investigate the role of survivin in the activation of NF‑κB p65 in ESCC. The expression levels of survivin, NF‑κB p65, inhibitor of nuclear factor κB kinase subunit α (IKKα) and inhibitor of nuclear factor κB kinase subunit β (IKKβ) were detected in ESCC tissue samples. Eca109 and KYSE150 cells were cultured and survivin activity was modulated via transfection with an overexpression plasmid, a small hairpin RNA plasmid and a specific inhibitor. Quantitative reverse transcription-polymerase chain reaction and western blotting assays were conducted to assess the effects of survivin on the expression levels of IKKα, IKKβ and NF‑κB p65. Cell cycle and apoptosis assays were conducted to detect surviving-dependent cellular behavior changes. In addition, the luciferase reporter gene assay and chromatin immunoprecipitation assay were conducted to determine the genomic sites responsible for surviving-induced activation of NF‑κB p65. The present study demonstrated that the expression of survivin is positively correlated with IKKα and IKKβ in ESCC tissues. Survivin affected the mRNA and protein expression levels of IKKα, IKKβ, and NF‑κB p65 in Eca109 and KYSE150 cells. Furthermore, survivin increased the transcriptional activity of the IKKβ promoter and bound to the IKKβ promoter region in the Eca109 cells. Downregulation of survivin arrested the cell cycle at the G2/M phase and induced apoptosis. Results of the present study suggest that survivin activates NF‑κB p65 in Eca109 cells via binding to the IKKβ promoter region and upregulating IKKβ promoter transcriptional activity. Survivin overexpression activates NF‑κB p65, which is important in the acquisition and maintenance of the oncogenic characteristics of ESCC.

A novel splice variant of XIAP-associated factor 1 (XAF1) is expressed in peripheral blood containing gastric cancer-derived circulating tumor cells

BACKGROUND

XIAP-associated factor 1 (XAF1) is ubiquitously expressed in normal tissues, but its suppression in cancer cells is strongly associated with tumor progression. Although downregulation of XAF1 is observed in tumors, its expression profile in the peripheral blood of cancer patients has not yet been investigated. Here, we identified a novel XAF1 splice variant in cancer cells and then investigated the expression level of this variant in peripheral blood containing gastric cancer-derived circulating tumor cells (CTCs).

METHODS

To identify splice variants, RT-PCR and DNA sequencing were performed in mRNAs extracted from many cancer cells. We then carried out quantitative RT-PCR to investigate expression in peripheral blood from all 96 gastric cancer patients and 22 healthy volunteers.

RESULTS

The XAF1 variant harbored a premature termination codon (PTC) and was differentially expressed in highly metastatic cancer cells versus the parental cells, and that nonsense-mediated mRNA decay (NMD) was suppressed in the variant-expressing cells. Furthermore, splice variants of XAF1 were upregulated in peripheral blood containing CTCs. In XAF1 variant-expressing patients, the expression levels of other NMD-targeted genes also increased, suggesting that the NMD pathway was suppressed in CTCs.

CONCLUSIONS

Our study identified a novel splice variant of XAF1 in cancer cells. This variant was regulated through the NMD pathway and accumulated in NMD-suppressed metastatic cancer cells and peripheral blood containing CTCs. The presence of XAF1 transcripts harboring the PTC in the peripheral blood may be useful as an indicator of NMD inhibition in CTCs.

Diagnostic value of multiple tumor markers for patients with esophageal carcinoma

BACKGROUND

Various studies assessing the diagnostic value of serum tumor markers in patients with esophageal cancer remain controversial. This study aims to comprehensively and quantitatively summarize the potential diagnostic value of 5 serum tumour markers in esophageal cancer.

METHODS

We systematically searched PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI) and Chinese Biomedical Database (CBM), through February 28, 2013, without language restriction. Studies were assessed for quality using QUADAS (quality assessment of studies of diagnostic accuracy). The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were pooled separately and compared with overall accuracy measures using diagnostic odds ratios (DORs) and symmetric summary receiver operating characteristic (SROC) curves.

RESULTS

Of 4391 studies initially identified, 44 eligible studies including five tumor markers met the inclusion criteria for the meta-analysis, while meta-analysis could not be conducted for 12 other tumor markers. Approximately 79.55% (35/44) of the included studies were of relatively high quality (QUADAS score≥7). The summary estimates of the positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) for diagnosing EC were as follows: CEA, 5.94/0.76/9.26; Cyfra21-1, 12.110.59/22.27; p53 antibody, 6.71/0.75/9.60; SCC-Ag, 7.66/0.68/12.41; and VEGF-C, 0.74/0.37/8.12. The estimated summary receiver operating characteristic curves showed that the performance of all five tumor markers was reasonable.

CONCLUSIONS

The current evidence suggests that CEA, Cyfra21-1, p53, SCC-Ag and VEGF-C have a potential diagnostic value for esophageal carcinoma.

Survivin - The inconvenient IAP

Although technically a member of the Inhibitor of Apoptosis (IAP) gene family, survivin has consistently defied assumptions, refuted predictions and challenged paradigms. Despite its more than 5500 citations currently in Medline, the biology of survivin has remained fascinatingly complex, its exploitation in human disease, most notably cancer, tantalizing, and its regulation of cellular homeostasis unexpectedly far-reaching. An inconvenient outsider that resists schemes and dogmas, survivin continues to hold great promise to unlock fundamental circuitries of cellular functions in health and disease.

Monitoring survivin expression in cancer: implications for prognosis and therapy

Survivin, a member of the inhibitor of apoptosis protein family, is one of the most cancer-specific proteins identified to date. Survivin expression is low or undetectable in most adult tissues, but, alternatively, is overexpressed in a large number of tumors. This multifunctional protein is recognized as a key regulator in apoptosis, proliferation and angiogenesis in the tumor environment. Several studies have shown a correlation between survivin upregulation and poor cancer prognosis, and, as expected, its downregulation or inactivation leads to inhibition of tumor growth. Therefore, survivin has attracted increasing attention both as a potential cancer biomarker and as a new target for anticancer therapies. This review summarizes and discusses survivin expression and its potential as a prognostic and diagnostic biomarker in different types of tumors, as well as provides an overview of the current therapeutic challenges of targeting survivin as a treatment strategy.

Survivin mRNA-circulating tumor cells predict treatment efficacy of chemotherapy and survival for advanced non-small cell lung cancer patients

The purpose of this prospective study was to evaluate the prognostic and predictive value of survivin mRNA-circulating tumor cells (CTCs) in peripheral blood of patients with advanced non-small cell lung cancer (NSCLC) who received first-line chemotherapy. Blood samples were collected from 78 patients with stage IIIB and IV NSCLC before (C0) and after 1 cycle (C1) and 3 cycles (C3) of chemotherapy. Survivin mRNA-CTCs were detected by real-time quantitative-PCR and correlated with treatment response and survival. The results showed that the presence of survivin mRNA-CTCs before and during chemotherapy was associated with histology type, tumor stage, and number of sites of metastasis. Moreover, the detection of survivin mRNA-CTCs after 1 and 3 cycles of chemotherapy was significantly associated with imaging response to treatment. Patients with positivity for survivin mRNA-CTCs at C0, C1, and C3 time points had significantly shorter progressive-free survival (PFS) and overall survival (OS) compared with patients without. Multivariate analysis using a Cox proportional hazards model revealed that the presence of survivin mRNA-CTCs after one and three chemotherapy cycles was a significant independent factor for worse PFS and OS. In conclusion, the detection of survivin mRNA-CTCs before and during chemotherapy is a prognostic and predictive factor correlated with poor PFS and OS in patients with advanced NSCLC.

Systematic review and meta-analysis of tumor biomarkers in predicting prognosis in esophageal cancer

BACKGROUND

Esophageal cancer (EC) is a frequently occurring cancer with poor prognosis despite combined therapeutic strategies. Many biomarkers have been proposed as predictors of adverse events. We sought to assess the prognostic value of biomarkers in predicting the overall survival of esophageal cancer and to help guide personalized cancer treatment to give patients the best chance at remission.

METHODS

We conducted a systematic review and meta-analysis of the published literature to summarize evidence for the discriminatory ability of prognostic biomarkers for esophageal cancer. Relevant literature was identified using the PubMed database on April 11, 2012, and conformed to the REMARK criteria. The primary endpoint was overall survival and data were synthesized with hazard ratios (HRs).

RESULTS

We included 109 studies, exploring 13 different biomarkers, which were subjected to quantitative meta-analysis. Promising markers that emerged for the prediction of overall survival in esophageal squamous cell cancer included VEGF (18 eligible studies, n=1476, HR=1.85, 95% CI, 1.55-2.21), cyclin D1 (12 eligible studies, n=1476, HR=1.82, 95% CI, 1.50-2.20), Ki-67 (3 eligible studies, n=308, HR=1.11, 95% CI, 0.70-1.78) and squamous cell carcinoma antigen (5 eligible studies, n=700, HR=1.28, 95% CI, 0.97-1.69); prognostic markers for esophageal adenocarcinoma included COX-2 (2 eligible studies, n=235, HR=3.06, 95% CI, 2.01-4.65) and HER-2 (3 eligible studies, n=291, HR=2.15, 95% CI, 1.39-3.33); prognostic markers for uncategorized ECs included p21 (9 eligible studies, n=858, HR=1.27, 95% CI, 0.75-2.16), p53 (31 eligible studies, n=2851, HR=1.34, 95% CI, 1.21-1.48), CRP (8 eligible studies, n=1382, HR=2.65, 95% CI, 1.64-4.27) and hemoglobin (5 eligible studies, n=544, HR=0.91, 95% CI, 0.83-1.00).

CONCLUSIONS

Although some modest bias cannot be excluded, this review supports the involvement of biomarkers to be associated with EC overall survival.

Prognostic value and targeted inhibition of survivin expression in esophageal adenocarcinoma and cancer-adjacent squamous epithelium

BACKGROUND

Survivin is an inhibitor of apoptosis and its over expression is associated with poor prognosis in several malignancies. While several studies have analyzed survivin expression in esophageal squamous cell carcinoma, few have focused on esophageal adenocarcinoma (EAC) and/or cancer-adjacent squamous epithelium (CASE). The purpose of this study was 1) to determine the degree of survivin up regulation in samples of EAC and CASE, 2) to evaluate if survivin expression in EAC and CASE correlates with recurrence and/or death, and 3) to examine the effect of survivin inhibition on apoptosis in EAC cells.

METHODS

Fresh frozen samples of EAC and CASE from the same patient were used for qRT-PCR and Western blot analysis, and formalin-fixed, paraffin-embedded tissue was used for immunohistochemistry. EAC cell lines, OE19 and OE33, were transfected with small interfering RNAs (siRNAs) to knockdown survivin expression. This was confirmed by qRT-PCR for survivin expression and Western blot analysis of cleaved PARP, cleaved caspase 3 and survivin. Survivin expression data was correlated with clinical outcome.

RESULTS

Survivin expression was significantly higher in EAC tumor samples compared to the CASE from the same patient. Patients with high expression of survivin in EAC tumor had an increased risk of death. Survivin expression was also noted in CASE and correlated with increased risk of distant recurrence. Cell line evaluation demonstrated that inhibition of survivin resulted in an increase in apoptosis.

CONCLUSION

Higher expression of survivin in tumor tissue was associated with increased risk of death; while survivin expression in CASE was a superior predictor of recurrence. Inhibition of survivin in EAC cell lines further showed increased apoptosis, supporting the potential benefits of therapeutic strategies targeted to this marker.

Gene diagnosis of micrometastases in regional lymph nodes of patients with stage I non-small cell lung cancer: impact on staging and prognosis

PURPOSE

The long-term survival of patients with completely resected stage I non-small cell lung cancer (NSCLC) is not optimal because of undetected lymph node micrometastasis at the time of surgery. The aim of this study is to evaluate the role of survivin and livin mRNA expression in histopathologically negative lymph nodes of stage I NSCLC patients as markers of micrometastasis.

METHODS

Clinical data and tissue samples of primary tumor and lymph nodes were collected from 44 patients with stage I NSCLC. Reverse-transcriptase-PCR (RT-PCR) was used to detect survivin and livin mRNA expression in these tumor and lymph node samples.

RESULTS

Survivin mRNA was detected in all tumors, and livin mRNA was detectable in 39 of the 44 primary tumors. The cut-off values of survivin and livin mRNA levels for diagnosing micrometastasis in lymph nodes were set up according to the expression of survivin and livin mRNA in control lymph nodes. Fifteen (34.1 %) of 44 stage I NSCCL patients had micrometastasis in lymph nodes by survivin and/or livin mRNA positive expression. Survival analysis showed higher rate of cancer recurrences and tumor-related death in patients with lymph node micrometastasis (P < 0.001 and P = 0.001, respectively). Tumor-free survival and overall survival were significantly worse in patients with lymph node micrometastasis compared with those without such micrometastasis (P = 0.007 and P = 0.01, respectively).

CONCLUSION

RT-RCR assay for survivin and livin mRNA can be considered as useful diagnostic tool for the detection of lymph node micrometastasis for stage I NSCLC patients.

OCT4 positively regulates Survivin expression to promote cancer cell proliferation and leads to poor prognosis in esophageal squamous cell carcinoma

Background

OCT4 and Survivin are important factors for cancer cell proliferation, renewal and dedifferentiation, and correlate with resistance to radiotherapy and chemotherapy in most human cancers, but their regulatory mechanisms are not well known.

Methodology/Principal Findings

In this study, 50 patients with esophageal squamous cell carcinoma (ESCC) were retrospectively analyzed. OCT4 was expressed in 13 cases (26%), and survivin was positively expressed in 31 cases (62%), examined by immunochemistry. OCT4 was found to be an independent predictive factor for median survival time, and the patients from the subgroup with both high expression of OCT4 and Survivin had the worst prognosis investigated by log-rank test. To further explore the molecular regulatory mechanism between OCT4 and Survivin, we constructed the specific small hairpin RNA (shRNA)-expressing vectors targeting OCT4 or/and Survivin and manipulated the expression of OCT4 and Survivin. By Western blotting and RT-PCR, we found that OCT4 could up-regulate Survivin expression in the esophageal cancer cell lines Eca109 and TE1. Simultaneously knockdown of OCT4 and Survivin expression induced cell apoptosis and G2-phase decrease of cell cycle by flow cytometry, and finally exerted an enhanced anti-proliferation potency in Eca109 and TE1 cell lines by MTT assay.

Conclusions

This study shows that OCT4 and Survivin expression were correlated with poor survival in patients with ESCC. OCT4 and Survivin may be regarded as targets in ESCC biotherapy.

[Disseminated and circulating tumor cells in gastrointestinal oncology]

Circulating (CTC) and disseminated tumor cells (DTC) represent two different steps of the metastatic process. As with other types of cancer, the recent development of techniques for the detection of CTC and DTC respectively in the blood and bone marrow of patients generated many results in digestive cancers. However, the interpretation of these results and of the prognostic value of CTC/DTC is often limited by the small cohort size and the heterogeneity of detection methods. The aim of this article is to review the different results and their clinical impact, and discuss the possible use of CTC and DTC as new biomarkers. First of all, it is important to take into account the variability of epithelial markers used for the initial stage of immunoselection of CTC/DTC as well as that of molecular or cytological markers used for the second stage of detection. In esophageal, gastric, pancreatic and hepatocellular carcinomas, and in the ileal and pancreatic neuroendocrine tumors, some studies showed a correlation between the detection of CTC and/or DTC and a clinical pejorative course, whether these tumors were at localized or metastatic stages. On colorectal cancer in the adjuvant setting, a recent meta-analysis showed an association between the detection of CTC in peripheral blood and disease-free survival or overall survival. These results are consistent with those of a study that identified detection of CTC as a prognostic factor for relapse in stage II. This last study concluded that it was necessary to achieve long-term evaluation of CTC as a biomarker to guide the decisions of chemotherapy for stage II. In metastatic colorectal cancer, the FDA approved in 2007 the use of pretherapeutic levels of CTC and its variations per-treatment, determined by CellSearch(®) technology, as a tool in treatments management. However, the modalities of this monitoring have to be specified and clinical benefit or the cost-effectiveness of a treatment based on this new biomarker has to be evaluated. Finally, the qualitative and quantitative monitoring of CTC could be a non-invasive tool to monitor changes in tumor biology throughout the disease, and thereby improve the understanding of the processes of dissemination and therapeutic resistance.

Prognostic and predictive roles for circulating biomarkers in gastrointestinal cancer

Circulating tumor cells (CTCs) and circulating free DNA (cfDNA) have been studied as promising prognostic and predictive tumor-derived biomarkers in the bloodstream of patients with gastrointestinal malignancies because they may be an alternative noninvasive tool to tumor tissue biopsies. Quantification and molecular characterization of CTCs and cfDNA may provide additional insights into cancer biology, potentially revealing novel targets to individualize cancer care. The present article aims to review the biology and current methods to assess CTCs and cfDNA, and the efforts to establish both tumor-derived biomarkers as prognostic and predictive factors in esophageal, gastric and colorectal cancer.

Clinical significance of stanniocalcin-1 detected in peripheral blood and bone marrow of esophageal squamous cell carcinoma patients

Background

Stanniocalcin-1 (STC-1) is a potential marker of disseminated tumor cells (DTCs). The aim of this study was to examine STC-1 expression in peripheral blood (PB) and bone marrow (BM) of esophageal squamous cell carcinoma (ESCC) patients, and to evaluate its clinical significance.

Methods

A total of 85 ESCC patients treated with radical resection were enrolled in this study. Immunohistochemistry was used to detect STC-1 protein expression in ESCC tissues. Nested RT-PCR was used to detect STC-1 mRNA expression in PB and BM.

Results

There were 71 cases (83.5%) showed a higher level of STC-1 protein expression in tumor tissues than in adjacent normal tissues (P < 0.001). Furthermore, the frequencies of STC-1 mRNA expression detected in PB and BM were 37.6% (32/85) and 21.2% (18/85), respectively, and together increased sensitivity to 48.2% (41/85), which was much higher than that in patients with benign esophageal disease (5.0%, 2/40, P < 0.001). In addition, STC-1 mRNA expression either in PB or BM was correlated with lymph metastasis, advanced stage and adverse 2-year progression free survival (PFS). In a multivariate analysis using the Cox proportional hazard model, STC-1 expression in PB and/or BM was an independent unfavorable prognostic factor for ESCC, apart from lymph metastasis and clinical stage.

Conclusions

STC-1 mRNA expression is a reliable marker for detection of DTCs in PB and BM of ESCC patients, and STC-1-positive DTCs may be a promising tool for diagnosis and prognosis assessment in ESCC.

Organ-specific markers in circulating tumor cell screening: an early indicator of metastasis-capable malignancy

Circulating tumor cells (CTCs) represent an important biological link in the spread of primary solid tumors to the metastatic disease responsible for most cancer mortality. Their detection in the peripheral blood of patients with many different carcinomas has shown that tumor-cell dissemination can proceed at an early stage of tumor development and their presence is associated with poor clinical outcomes, particularly in metastatic disease. In this article we describe how the increasingly sensitive isolation and detailed molecular characterization of CTCs has greatly improved our understanding of metastatic proliferation. We focus on how CTC detection and knowledge of the molecular architecture of these cells can serve as biomarkers to signal metastasis-capable disseminating cells and predict therapy-specific response. This has marked clinical utility for improved selection of systemic therapies to the individual needs of a cancer patient, real-time monitoring of metastatic disease treatments and the development of new targeted therapies.

Circulating cancer cells

Circulating tumour cells (CTCs) can be detected in the blood of many patients with different types of early or advanced cancer using antibody-based assays or molecular methods. In many studies the detection and quantification of CTCs has been linked to unfavourable prognosis. CTC detection offers the opportunity for individualized risk assessment beyond that determined by TNM staging. However, discordant results have been reported when different methodologies for CTC detection were used. Therefore, well-standardized detection methods cross-validated between different laboratories are still needed. CTCs are a heterogeneous population of cells with biological characteristics often different from those of their respective primary tumour cells. Pilot studies have shown that phenotyping of CTCs could be used to predict response to targeted therapies. In the era of biological therapeutics, CTC characterization at different time points during the course of disease may provide useful predictive information for the selection of the most appropriate treatment. Therefore, in the future, CTC detection and characterization might become a valuable tool to refine prognosis and serve as a real-time tumour biopsy for individually tailored cancer therapy. Prospective randomized studies are warranted to evaluate the utility of assessing and monitoring CTCs and modifying accordingly treatment strategies in order to improve the clinical outcome of cancer patients.

Disseminated and circulating tumor cells in gastrointestinal oncology

Circulating (CTCs) and disseminated tumor cells (DTCs) are two different steps in the metastatic process. Several recent techniques have allowed detection of these cells in patients, and have generated many results using different isolation techniques in small cohorts. Herein, we review the detection results and their clinical consequence in esophageal, gastric, pancreatic, colorectal, and liver carcinomas, and discuss their possible applications as new biomarkers.

Using detection of survivin-expressing circulating tumor cells in peripheral blood to predict tumor recurrence following curative resection of gastric cancer

BACKGROUND AND OBJECTIVES

The present study was designed to investigate the clinicopathological role of survivin-expressing circulating tumor cells (CTCs) and to determine whether the presence of survivin-expressing CTCs is an independent predictor of tumor recurrence following curative resection of gastric cancer.

METHODS

This study included 98 patients who underwent potentially curative resection. Reverse transcription polymerase chain reaction enzyme linked immunosorbent assay (RT-PCR ELISA) was used to measure survivin mRNA in peripheral blood.

RESULTS

Of the 98 patients studied, 45 (45.9%) were positive for survivin mRNA. Survivin mRNA expression correlated with Lauren classification (P < 0.001), pathological tumor (pT) stage (P < 0.001), pathological tumor node metastasis (pTNM) stage (P = 0.009), and degree of differentiation (P = 0.001). The pTNM stage and the status of survivin mRNA were independent prognostic factors of disease-free survival (P = 0.007 and <0.001, respectively).

CONCLUSIONS

The detection of CTCs expressing survivin mRNA could be a good clinical biomarker used to predict the prognosis of patients with curatively resected gastric cancer.

Role of survivin gene promoter polymorphism (-31G>C) in susceptibility and survival of esophageal cancer in northern India

BACKGROUND AND AIM

Survivin is an upregulated inhibitor of apoptosis protein in esophageal cancer (EC), and a promoter region polymorphism (-31G>C) in the survivin gene has been reported as a modulator of gene expression. We aim to explore the role of survivin -31G>C polymorphism in susceptibility and survival of EC patients in northern Indian population.

MATERIALS AND METHODS

A case-control study was performed in 500 subjects (250 EC patients and 250 controls), and genotyping was done by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method.

RESULTS

Survivin CC genotype was found to be significantly associated with EC susceptibility [odds ratio (OR) = 2.29; 95% confidence interval (CI) = 1.27-4.14; P = 0.006], particularly in males (OR = 4.91; 95% CI = 2.19-11.02; P = 0.0001) having squamous cell carcinoma (SCC) histopathology (OR = 2.4; 95% CI = 1.36-4.21; P = 0.002) at middle third esophagus location (OR = 2.60; 95% CI = 1.40-4.82; P = 0.002). Patients carrying CC genotype were found to have higher susceptibility to lymph node metastasis (OR = 2.82; 95% CI = 1.46-5.48; P = 0.002). However, on survival analysis, no prognostic role of survivin -31G>C polymorphism was detected. In case-only analysis, no gene-environment interaction was observed.

CONCLUSION

Survivin promoter region polymorphism (-31G>C) is associated with susceptibility and clinical characteristics but not prognosis of esophageal cancer in northern Indian population.

Preoperative survivin mRNA detection in peripheral blood is an independent predictor of outcome in esophageal carcinoma

AIMS

Survivin (SVV) mRNA expression levels in peripheral blood of patients with gastrointestinal malignancies change significantly during the course of treatment. We wanted to scrutinize these findings in patients with esophageal carcinoma and furthermore evaluate whether the detection of mRNA and the change in detecting ability have an association with overall survival.

MATERIALS & METHODS

Whole blood was drawn 1 day pre- and 10 days post-operatively from 62 patients with esophageal carcinoma. Tumor cells were enriched from whole blood by density-gradient centrifugation prior to extraction of total cellular RNA and subsequent direct quantitative reverse transcriptase-PCR assays.

RESULTS

SVV was detectable in 48 out of 62 patients (77%). Stepwise multivariate Cox linear regression models demonstrated a significant and independent association of measured SVV with overall survival (6.6 exp[b]; 95% CI: 1.97-22.12; p = 0.002). Increased SVV levels after the operation were linked to shorter overall survival (p = 0.04).

CONCLUSION

Preoperative SVV expression levels appear to be associated with overall survival in patients with esophageal cancers. Increasing levels could potentially indicate a higher risk for shorter overall survival and therefore demand adapted treatment modalities.

Detection of survivin protein in aqueous humor and serum of retinoblastoma patients and its clinical significance

OBJECTIVES

There is growing biomedical interest in survivin as a diagnostic and prognostic factor in human neoplasms. The present work assessed survivin expression in retinoblastoma.

DESIGN AND METHODS

Survivin was quantitatively measured in 82 aqueous humor and serum samples from 41 children with retinoblastoma and nonmalignant ophthalmic diseases. After treatment, 12 serum samples from retinoblastoma patients were included.

RESULTS

Survivin levels were higher in aqueous humor and serum of retinoblastoma patients than the controls (P<0.05). In aqueous, it was significantly correlated with the tumor stage and optic nerve affection. The best cutoff values for survivin in aqueous and serum that differentiate between retinoblastoma and nonmalignant ophthalmic diseases were 25.2 pg/mg protein and 12.9 pg/mL, respectively. The sensitivity and specificity were 100% and 90% in serum and 94% and 48% in aqueous, respectively. Serum survivin has decreased significantly after treatment.

CONCLUSION

Measurement of survivin protein might have a great diagnostic and prognostic potential in retinoblastoma.