Training in optical diagnosis in community hospitals is associated with improved recognition and treatment of T1 CRC: a prospective multicenter intervention study (OPTICAL II).

BACKGROUND AND STUDY AIMS: Recognition of T1 colorectal cancer (CRC) is difficult, with sensitivities of 35-60% in Western countries. We evaluated the real-life effects of the implementation of the OPTICAL model, a recently developed structured and validated prediction model, in Dutch community hospitals. PATIENTS AND METHODS: In this prospective multicenter study, 383 endoscopists from 40 hospitals were invited to follow an e-learning on the OPTICAL-model, to increase sensitivity for detecting T1CRC in non-pedunculated polyps. Next, real-life recognition of T1CRC was evaluated in 25 hospitals. Endoscopic and pathologic reports of T1CRCs detected during the next year were collected retrospectively while endoscopists were unaware of this evaluation. Sensitivity for recognition of T1CRC, R0 resection rate, and treatment modality were compared for trained vs. untrained endoscopists and for recognised vs. unrecognised T1CRCs. RESULTS: Within 1 year after the e-learning 251 endoscopists detected 528 non-pedunculated T1CRCs, 118 (47%) of the endoscopist were trained. T1CRCs had a median size of 20mm and were mainly located in the distal colorectum (66%). Trained endoscopists recognised T1CRCs more frequently than untrained endoscopists (sensitivity 74% vs. 62%; mixed model analysis OR 2.90; 95%CI 1.54-5.45. A higher rate of R0 resection was seen for T1CRCs detected by trained endoscopists (69% vs. 56%, OR 1.73; 95%CI 1.03-2.91). CONCLUSION: Training in optical recognition of T1CRCs in community hospitals was associated with an increase in sensitivity for T1CRCs. Recognition led to a higher rate of en bloc local excision, resulting in higher R0-resection rates. This may be an important step towards more organ-preserving strategies.

Standardised training for endoscopic mucosal resection of large non-pedunculated colorectal polyps to reduce recurrence (*STAR-LNPCP study): a multicentre cluster randomised trial.

OBJECTIVE: Endoscopic mucosal resection (EMR) is the preferred treatment for non-invasive large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs) but is associated with an early recurrence rate of up to 30%. We evaluated whether standardised EMR training could reduce recurrence rates in Dutch community hospitals. DESIGN: In this multicentre cluster randomised trial, 59 endoscopists from 30 hospitals were randomly assigned to the intervention group (e-learning and 2-day training including hands-on session) or control group. From April 2019 to August 2021, all consecutive EMR-treated LNPCPs were included. Primary endpoint was recurrence rate after 6 months. RESULTS: A total of 1412 LNPCPs were included; 699 in the intervention group and 713 in the control group (median size 30 mm vs 30 mm, 45% vs 52% size, morphology, site and access (SMSA) score IV, 64% vs 64% proximal location). Recurrence rates were lower in the intervention group compared with controls (13% vs 25%, OR 0.43; 95% CI 0.23 to 0.78; p=0.005) with similar complication rates (8% vs 9%, OR 0.93; 95% CI 0.64 to 1.36; p=0.720). Recurrences were more often unifocal in the intervention group (92% vs 76%; p=0.006). In sensitivity analysis, the benefit of the intervention on recurrence rate was only observed in the 20-40 mm LNPCPs (5% vs 20% in 20-29 mm, p=0.001; 10% vs 21% in 30-39 mm, p=0.013) but less evident in ≥40 mm LNPCPs (24% vs 31%; p=0.151). In a post hoc analysis, the training effect was maintained in the study group, while in the control group the recurrence rate remained high. CONCLUSION: A compact standardised EMR training for LNPCPs significantly reduced recurrences in community hospitals. This strongly argues for a national dedicated training programme for endoscopists performing EMR of ≥20 mm LNPCPs. Interestingly, in sensitivity analysis, this benefit was limited for LNPCPs ≥40 mm. TRIAL REGISTRATION NUMBER: NTR7477.

Laparoscopic ileocaecal resection versus infliximab for terminal ileitis in Crohn's disease: a randomised controlled, open-label, multicentre trial.

BACKGROUND: Treatment of patients with ileocaecal Crohn's disease who have not responded to conventional therapy is commonly scaled up to biological agents, but surgery can also offer excellent short-term and long-term results. We compared laparoscopic ileocaecal resection with infliximab to assess how they affect health-related quality of life. METHODS: In this randomised controlled, open-label trial, in 29 teaching hospitals and tertiary care centres in the Netherlands and the UK, adults with non-stricturing, ileocaecal Crohn's disease, in whom conventional therapy has failed were randomly allocated (1:1) by an internet randomisation module with biased-coin minimisation for participating centres and perianal fistula to receive laparoscopic ileocaecal resection or infliximab. Eligible patients were aged 18-80 years, had active Crohn's disease of the terminal ileum, and had not responded to at least 3 months of conventional therapy with glucocorticosteroids, thiopurines, or methotrexate. Patients with diseased terminal ileum longer than 40 cm or abdominal abscesses were excluded. The primary outcome was quality of life on the Inflammatory Bowel Disease Questionnaire (IBDQ) at 12 months. Secondary outcomes were general quality of life, measured by the Short Form-36 (SF-36) health survey and its physical and mental component subscales, days unable to participate in social life, days on sick leave, morbidity (additional procedures and hospital admissions), and body image and cosmesis. Analyses of the primary outcome were done in the intention-to-treat population, and safety analyses were done in the per-protocol population. This trial is registered at the Dutch Trial Registry (NTR1150). FINDINGS: Between May 2, 2008, and October 14, 2015, 73 patients were allocated to have resection and 70 to receive infliximab. Corrected for baseline differences, the mean IBDQ score at 12 months was 178·1 (95% CI 171·1-185·0) in the resection group versus 172·0 (164·3-179·6) in the infliximab group (mean difference 6·1 points, 95% CI -4·2 to 16·4; p=0·25). At 12 months, the mean SF-36 total score was 112·1 (95% CI 108·0-116·2) in the resection group versus 106·5 (102·1-110·9) in the infliximab group (mean difference 5·6, 95% CI -0·4 to 11·6), the mean physical component score was 47·7 (45·7-49·7) versus 44·6 (42·5-46·8; mean difference 3·1, 4·2 to 6·0), and the mean mental component score was 49·5 (47·0-52·1) versus 46·1 (43·3-48·9; mean difference 3·5, -0·3 to 7·3). Mean numbers of days of sick leave were 3·4 days (SD 7·1) in the resection group versus 1·4 days (4·7) in the infliximab group (p<0·0001), days not able to take part in social life were 1·8 days (6·3) versus 1·1 days (4·5; p=0·20), days of scheduled hospital admission were 6·5 days (3·8) versus 6·8 days (3·2; p=0·84), and the number of patients who had unscheduled hospital admissions were 13 (18%) of 73 versus 15 (21%) of 70 (p=0·68). Body-image scale mean scores in the patients who had resection were 16·0 (95% CI 15·2-16·8) at baseline versus 17·8 (17·1-18·4) at 12 months, and cosmetic scale mean scores were 17·6 (16·6-18·6) versus 18·6 (17·6-19·6). Surgical intervention-related complications classified as IIIa or worse on the Clavien-Dindo scale occurred in four patients in the resection group. Treatment-related serious adverse events occurred in two patients in the infliximab group. During a median follow-up of 4 years (IQR 2-6), 26 (37%) of 70 patients in the infliximab group had resection, and 19 (26%) of 73 patients in the resection group received anti-TNF. INTERPRETATION: Laparoscopic resection in patients with limited (diseased terminal ileum <40 cm), non-stricturing, ileocaecal Crohn's disease in whom conventional therapy has failed could be considered a reasonable alternative to infliximab therapy. FUNDING: Netherlands Organisation for Health Research and Development.

Accuracy for optical diagnosis of small colorectal polyps in nonacademic settings.

BACKGROUND & AIMS: When small colorectal lesions are accurately characterized, adenomas can be removed and discarded without formal histopathology analysis. Previous studies in an academic setting showed that many lesions can be managed accurately on the basis of their endoscopic image (optical diagnosis). We performed a prospective study to assess the accuracy of optical diagnosis of small colorectal polyps in a nonacademic setting (the DISCOUNT trial) by using high-resolution endoscopy (HRE) and narrow-band imaging (NBI). METHODS: During colonoscopy, 1 of 3 nonacademic endoscopists characterized small lesions and declared whether this was done with low or high confidence. In cases of high confidence, the endoscopists decided whether lesions should be removed and discarded or whether they could be left in situ. A surveillance interval was then recommended on-site. RESULTS: Of 215 patients in the study, 108 were found to have 281 small lesions. Of these lesions, 231 were characterized with high confidence by using HRE or NBI; the level of corresponding sensitivity was 77.0% (95% confidence interval, 68.4-83.8), and specificity was 78.8% (95% confidence interval, 70.6-85.2). Of these lesions, 164 were assigned for removal, and 67 were assigned to remain in situ, including 9 adenomas. In 54 patients, a surveillance interval could be recommended on-site that was in line with Dutch guidelines for 44 patients. CONCLUSIONS: Even though many lesions were characterized by HRE or NBI with high confidence, optical diagnosis in a nonacademic setting proved to be disappointing, with a sensitivity of 77.0% and a specificity of 78.8%. Many lesions were accurately assigned to be removed or remain in situ, although few adenomas were assigned to remain in situ. Also, 19% of on-site recommendations for a surveillance interval proved to be inaccurate.

Endoscopic trimodal imaging detects colonic neoplasia as well as standard video endoscopy.

BACKGROUND & AIMS: Endoscopic trimodal imaging (ETMI) is a novel endoscopic technique that combines high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) that has only been studied in academic settings. We performed a randomized, controlled trial in a nonacademic setting to compare ETMI with standard video endoscopy (SVE) in the detection and differentiation of colorectal lesions. METHODS: The study included 234 patients scheduled to receive colonoscopy who were randomly assigned to undergo a colonoscopy in tandem with either ETMI or SVE. In the ETMI group (n=118), first examination was performed using HRE, followed by AFI. In the other group, both examinations were performed using SVE (n=116). In the ETMI group, detected lesions were differentiated using AFI and NBI. RESULTS: In the ETMI group, 87 adenomas were detected in the first examination (with HRE), and then 34 adenomas were detected during second inspection (with AFI). In the SVE group, 79 adenomas were detected during the first inspection, and then 33 adenomas were detected during the second inspection. Adenoma detection rates did not differ significantly between the 2 groups (ETMI: 1.03 vs SVE: 0.97, P=.360). The adenoma miss-rate was 29% for HRE and 28% for SVE. The sensitivity, specificity, and accuracy of NBI in differentiating adenomas from nonadenomatous lesions were 87%, 63%, and 75%, respectively; corresponding values for AFI were 90%, 37%, and 62%, respectively. CONCLUSIONS: In a nonacademic setting, ETMI did not improve the detection rate for adenomas compared with SVE. NBI and AFI each differentiated colonic lesions with high levels of sensitivity but low levels of specificity.

Combining autofluorescence imaging and narrow-band imaging for the differentiation of adenomas from non-neoplastic colonic polyps among experienced and non-experienced endoscopists.

OBJECTIVES: Endoscopic tri-modal imaging incorporates high-resolution white-light endoscopy (HR-WLE), narrow-band imaging (NBI), and autofluorescence imaging (AFI). Combining these advanced techniques may improve endoscopic differentiation between adenomas and non-neoplastic polyps. In this study, we aimed to assess the interobserver variability and accuracy of HR-WLE, NBI, and AFI for polyp differentiation and to evaluate the combined use of AFI and NBI. METHODS: First, still images of 50 polyps (22 adenomas; median 3 mm) were randomly displayed to three experienced and four non-experienced endoscopists. All HR-WLE and NBI images were scored for Kudo classification and AFI images for color. Second, the combined AFI and NBI images were assessed using a newly developed algorithm by six additional non-experienced endoscopists. RESULTS: The outcomes measured were interobserver agreement and diagnostic accuracy using histopathology as reference standard. Experienced endoscopists had better interobserver agreement for NBI (kappa=0.77) than for AFI (kappa=0.33), whereas non-experienced endoscopists had better agreement for AFI (kappa=0.58) than for NBI (kappa=0.33). The accuracies of HR-WLE, NBI, and AFI among experienced endoscopists were 65, 70, and 74, respectively. Figures among non-experienced endoscopists were 57, 63, and 77. The algorithm was associated with a significantly higher accuracy of 85% among all observers (P<0.023). These figures were confirmed in the second evaluation study. CONCLUSIONS: Non-experienced endoscopists have better interobserver agreement and accuracy for AFI than for HR-WLE or NBI, indicating that AFI is easier to use for polyp differentiation in non-experienced setting. The newly developed algorithm, combining information of AFI and NBI together, had the highest accuracy and obtained equal results between experienced and non-experienced endoscopists.

Laparoscopic ileocolic resection versus infliximab treatment of distal ileitis in Crohn's disease: a randomized multicenter trial (LIR!C-trial).

BACKGROUND: With the availability of infliximab, nowadays recurrent Crohn's disease, defined as disease refractory to immunomodulatory agents that has been treated with steroids, is generally treated with infliximab. Infliximab is an effective but expensive treatment and once started it is unclear when therapy can be discontinued. Surgical resection has been the golden standard in recurrent Crohn's disease. Laparoscopic ileocolic resection proved to be safe and is characterized by a quick symptom reduction. The objective of this study is to compare infliximab treatment with laparoscopic ileocolic resection in patients with recurrent Crohn's disease of the distal ileum with respect to quality of life and costs. METHODS/DESIGN: The study is designed as a multicenter randomized clinical trial including patients with Crohn's disease located in the terminal ileum that require infliximab treatment following recent consensus statements on inflammatory bowel disease treatment: moderate to severe disease activity in patients that fail to respond to steroid therapy or immunomodulatory therapy. Patients will be randomized to receive either infliximab or undergo a laparoscopic ileocolic resection. Primary outcomes are quality of life and costs. Secondary outcomes are hospital stay, early and late morbidity, sick leave and surgical recurrence. In order to detect an effect size of 0.5 on the Inflammatory Bowel Disease Questionnaire at a 5% two sided significance level with a power of 80%, a sample size of 65 patients per treatment group can be calculated. An economic evaluation will be performed by assessing the marginal direct medical, non-medical and time costs and the costs per Quality Adjusted Life Year (QALY) will be calculated. For both treatment strategies a cost-utility ratio will be calculated. Patients will be included from December 2007. DISCUSSION: The LIR!C-trial is a randomized multicenter trial that will provide evidence whether infliximab treatment or surgery is the best treatment for recurrent distal ileitis in Crohn's disease. TRIAL REGISTRATION: Nederlands Trial Register NTR1150.

Adenoviral serotypes in gene therapy for esophageal carcinoma.

PURPOSE: Adenoviral gene therapy could potentially play a role in the treatment of esophageal cancer and Barrett's esophagus. The adenoviruses can be categorized in different serotypes. The goal of the present study was to investigate the transduction efficacy of different adenoviral serotypes in different models of esophageal cancer and Barrett's esophagus. METHODS: Chimeras of the adenoviral serotype 5 backbone and fibers of serotypes 5, 16, 35, 40, and 50 were constructed with PCR technology. For esophageal cancer, cell lines were used originating from with adenocarcinoma and squamous cell carcinoma, respectively. Differentiating Caco-2 cells were used as an in vitro model for Barrett's esophagus. GFP was used as a reporter gene and transduction efficacy was assessed by flow cytometry. RESULTS: Overall transduction was rather efficient in the cancer cell lines. Especially serotype 16 and 50 exhibited an improved transduction compared with the other serotypes. In the Caco-2 cell lines, we observed a decreased transduction upon differentiation of the cells. All serotypes had a very limited transduction and no serotype had an additional value in this setting. CONCLUSIONS: Some serotypes could have an additional value in the development of gene therapy for esophageal cancer. Especially serotype 16 and 50 exhibited an improved transduction in esophageal cancer cells compared with the native serotype 5. In the setting of Barrett's esophagus, none of the serotypes had an improved potency as in differentiated intestinal cells all serotypes had a very limited transduction.

The current state of cancer gene therapy and its application in esophageal carcinoma.

UNLABELLED: Advances in molecular genetics have accelerated the understanding of the genetic basis of many diseases. This is particularly true for esophageal adenocarcinoma with its well-defined premalignant lesions. At the same time, remarkable progress in recombinant DNA technology has enabled the development of molecular treatments for inherited disorders, infectious diseases and cancer. In recent years, especially the development of gene therapy systems as new treatment or prevention strategies for various malignant diseases has been explored. The present article deals with the general principles of gene therapy and then focuses on how these principles can be applied to esophageal cancer. Subsequently, the scarcely available experimental data from the literature are briefly reviewed. Finally, we summarize our experimental work over the last few years. Our main goal has been to develop an efficient and selective gene delivery system in order to maximize the proportion of successfully transduced tumor cells while sparing normal cells. CONCLUSION: The field of cancer gene therapy has evolved tremendously, with promising developments especially in the field of targeting and novel therapeutic genes. However, substantial research is still needed before gene therapy can play a significant role in the management of esophageal cancer. The focus of this research should be on further developing adequate experimental models as well as on improving gene-delivering vectors. Although it is unlikely that cancer gene therapy will replace the conventional methods of treatment, selective and efficient vectors may be used for patients with Barrett's esophagus or as adjuvant therapy for patients with esophageal cancer in the future.

Gene therapy for barrett's esophagus: adenoviral gene transfer in different intestinal models.

Adenoviral gene therapy could potentially be used for treatment of patients with a Barrett's esophagus. In order to study the feasibility of this approach it is important to study adenoviral intestinal transduction both in vitro and in vivo. In the present study, we used differentiating Caco-2 cells, closed intestinal loops and a Barrett's esophagus rat model to test transduction of adenoviruses expressing green fluorescent protein. We observed a decreased adenoviral transduction from 18.6 to 2.3% in undifferentiated and differentiated Caco-2 cells, respectively. This could be improved by the use of the mucolytic agent N-acetylcysteine (NAC) and the polycation diethylaminoethyl-dextran (DEAE-dextran), which improved transduction in differentiated cells five- and ten-fold, respectively. Also an RGD-retargeted adenovirus showed an improved transduction in differentiated cells. In closed intestinal loops adenoviral transduction was limited and the use of NAC and DEAE-dextran or RGD targeting had little effect. The Barrett's esophagus rat model consisted of an esophagojejunostomy, which results in a Barrett's esophagus and esophageal tumors within 6 months. Adenoviral transduction in this model was limited and mainly localized in the basal layer of normal esophagus and stromal tissue of a Barrett's segment. We conclude that although the adenovirus shows promising results in vitro, the current adenoviral vectors are probably not suitable for patients with Barrett's esophagus.

Loss of heterozygosity and immunohistochemistry of adenocarcinomas of the esophagus and gastric cardia.

PURPOSE: Adenocarcinomas of the distal esophagus and gastric cardia are two tumors that have many features in common. They have similar prognoses, treatment modalities, and patterns of dissemination. The etiology is different, with gastroesophageal reflux disease playing a major role for esophageal adenocarcinoma, in contrast to adenocarcinoma of the gastric cardia. In the present study, we investigated several genetic and immunohistochemical features of adenocarcinomas of the distal esophagus and gastric cardia. EXPERIMENTAL DESIGN: Sixty-two resection specimens of either adenocarcinoma of the esophagus or adenocarcinoma of the gastric cardia were carefully selected. The genetic analysis included loss of heterozygosity of several tumor suppressor genes known to be involved in esophagogastric carcinogenesis. Immunohistochemical studies included the analysis of p53, c-Met, c-erbB-2, beta-catenin, and cyclooxygenase-2. In addition, a mutation analysis of the Tcf1 gene was done by direct sequencing. RESULTS: Patients with cardiac carcinoma had a significantly worse tumor stage and poorer differentiation on histology. Loss of heterozygosity analysis did not reveal significant differences between esophageal adenocarcinoma and cardiac adenocarcinoma. Immunohistochemical analysis revealed significantly more nuclear accumulation of beta-catenin and overexpression of cyclooxygenase-2 in patients with esophageal adenocarcinoma, compared with patients with cardiac carcinoma. No mutation was found in the Tcf1 gene in either tumor type. CONCLUSIONS: Although adenocarcinomas of the distal esophagus and gastric cardia have many features in common, we have found some evidence that they might form two different entities.

The presence and mucin histochemistry of cardiac type mucosa at the esophagogastric junction.

OBJECTIVES: Traditionally, the gastric cardia has been described as a native part of the stomach connecting to the esophagus. In recent literature, however, it is suggested that the cardia is an acquired lesion that develops due to gastroesophageal reflux disease. As a contribution to this debate, we evaluated the presence of cardiac mucosa at the esophagogastric junction (EGJ) in a random group of patients who presented at our endoscopy unit. METHODS: In 253 unselected patients, biopsies were taken from the EGJ. In order to prevent sampling error, we selected only those EGJ biopsies in which the squamocolumnar junction (SCJ) was present in the histological biopsy material. Fifty-five patients were excluded since the SCJ was located proximal to the EGJ in the esophagus. The type of columnar mucosa immediately distal to the SCJ, and its mucin histochemistry, were assessed. The columnar mucosa was categorized as purely cardiac, oxyntocardiac, or fundic mucosa. RESULTS: In 63 of the 198 patients, the SCJ was actually present in the EGJ biopsies. Purely cardiac mucosa was present in 39 (62%) biopsies and oxyntocardiac mucosa was present in 24 (38%) biopsies. Fundic mucosa was not seen directly adjacent to squamous epithelium. Acid mucins were present in 23 (37%) patients and they correlated with histological esophagitis and presence of H. pylori in the cardia. CONCLUSIONS: Cardiac mucosa was uniformly present adjacent to the squamous epithelium at the EGJ. This argues against the hypothesis that the gastric cardia is an acquired metaplastic lesion. The presence of acid mucins was frequently observed and could be a pathological condition as it was associated with histological esophagitis and the presence of H. pylori in the cardia.

Gene therapy for esophageal carcinoma: the use of an explant model to test adenoviral vectors ex vivo.

Adenoviral gene therapy might be a promising therapeutic strategy for esophageal carcinoma. However, adenoviral transduction efficacy in vivo is still limited. This efficacy can be improved by the insertion of an Arg-Gly-Asp (RGD) peptide in the HI-loop of the viral fiber knob. Indeed in established esophageal cell lines, we observed an up to six-fold improved transduction using the RGD-targeted adenovirus. Established cell lines, however, are easily transformed and do not represent the more complex in vivo histology and anatomy. Therefore, we set up an esophageal explant model using esophageal biopsies from patients. Viability is a limiting factor for this system. Cultured squamous epithelium, intestinal metaplasia and squamous cell carcinoma had a sufficient viability to study adenoviral transduction. Viability of the cultured adenocarcinoma biopsies was poor. Adenoviral transduction in the explant model was poor and was localized in particular cells. The transduction of the nontargeted and RGD-targeted adenovirus was similar in localization and efficacy. In conclusion, we established an esophageal explant system to test the transduction of adenoviral vectors ex vivo. The transduction was limited and localized in specific cells. RGD-targeted adenovirus did not show an improved transduction in this system.

A genetically retargeted adenoviral vector enhances viral transduction in esophageal carcinoma cell lines and primary cultured esophageal resection specimens.

OBJECTIVE: To evaluate if an integrin-retargeted adenoviral vector could establish a more efficient and tumor-specific gene transfer in esophageal carcinoma cells. SUMMARY BACKGROUND DATA: Although preclinical data indicated that adenoviral gene therapy could be a promising novel treatment modality for various malignancies, clinical results are often disappointing. An important problem is the decreased tumoral expression of the Coxsackie and adenovirus receptor (CAR), which mediates adenoviral entry. Retargeting the adenoviral vector to other cellular receptors, by inserting an arginine-glycine-aspartate (RGD) tripeptide in the fiber knob, might overcome this problem. METHODS: Four esophageal carcinoma cell lines and 10 fresh surgical resection specimens were cultured. All were infected with the native adenovirus (Ad) and the retargeted adenovirus (AdRGD), encoding for the reporter genes luciferase or Green Fluorescent Protein to analyze gene transfer efficiency. RESULTS: In all cell lines, an increase in viral expression per cell and an increase in the percentage of transduced cells were seen with the retargeted adenovirus. Also, in the primary cultures of carcinoma cells, a more efficient gene transfer was seen when the retargeted vector was used. This phenomenon was less pronounced in normal cells, indicating that the RGD virus transduces tumor cells more efficiently than normal cells. CONCLUSIONS: This study demonstrates that an RGD retargeted adenovirus infects human esophageal carcinoma cells with enhanced efficiency, while in normal esophageal cells this effect is less pronounced. Therefore, this retargeted vector is expected to have a better performance in vivo, when compared with nonretargeted vectors used for cancer gene therapy so far.