[Treatment strategies for recurrent rectal cancer]. / Therapiestrategien beim Rektumkarzinomrezidiv.

Multimodal treatment approaches with neoadjuvant radiotherapy and chemotherapy followed by oncological and total mesorectal excision (TME) have significantly reduced the recurrence rate even in locally advanced rectal cancer. Nevertheless, up to 10% of patients develop a local relapse. Surgical R0 resection is the only chance of a cure in the treatment of locally recurrent rectal cancer (LRRC). Due to the altered anatomy and physiology of the true pelvis as a result of the pretreatment and operations as well as the localization and extent of the recurrence, the treatment decision is individualized and remains a challenge for the interdisciplinary team. Even locally advanced tumors with involvement of adjacent structures can be treated in designated centers using multimodal treatment concepts with potentially curative intent.

COMPASS: deCOMPressing stomA and two-Stage elective resection vs. emergency reSection in patients with left-sided obstructive colon cancer.

BACKGROUND: Colorectal cancer stands as a prevalent cause of cancer-related mortality, necessitating effective treatment strategies. Acute colonic obstruction occurs in approximately 20% of patients and represents a surgical emergency with substantial morbidity and mortality. The optimal approach for managing left-sided colon cancer with acute colonic obstruction remains debatable, with no consensus on whether emergency resection or bridge-to-surgery, involving initial decompressing stoma and subsequent elective resection after recovery, should be employed. Current studies show a decrease in morbidity and short-term mortality for the bridge-to-surgery approach, yet it remains unclear if the long-term oncological outcome is equivalent to emergency resection. METHODS: This prospective, randomized, multicenter trial aims to investigate the management of obstructive left-sided colon cancer in a comprehensive manner. The study will be conducted across 26 university hospitals and 40 academic hospitals in Germany. A total of 468 patients will be enrolled, providing a cohort of 420 evaluable patients, with an equal distribution of 210 patients in each treatment arm. Patients with left-sided colon cancer, defined as cancer between the left splenic flexure and > 12 cm ab ano and obstruction confirmed by X-ray or CT scan, are eligible. Randomization will be performed in a 1:1 ratio, assigning patients either to the oncological emergency resection group or the bridge-to-surgery group, wherein patients will undergo diverting stoma and subsequent elective oncological resection after recovery. The primary endpoint of this trial will be 120-day mortality, allowing for consideration of the time interval between diverting stoma and resection. DISCUSSION: The findings derived from this trial possess the potential to reshape the current clinical approach of emergency resection for obstructive left-sided colon cancer by favoring the bridge-to-surgery practice, provided that a reduction in morbidity can be achieved without compromising the oncological long-term outcome. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) under the identifier DRKS00031827. Registered on May 15, 2023. PROTOCOL: 28.04.2023, protocol version 2.0F.

Long-Term Observation of Patients With Cancer - an Entity-Independent Registry for Healthcare and Translational Research at the University Medicine Dresden (Cancer-Reg-VT). / Langzeitbeobachtung von Patienten mit Krebserkrankungen ­ ein entitätsunabhängiges Register für Versorgungsforschung und translationale Forschung an der Universitätsmedizin Dresden (Cancer-Reg-VT).

INTRODUCTION: Translational research is important, especially in medicine where decisions affect people's lives. Clinical registries and the studies embedded in them allow the depiction of actual care practice under routine conditions. Translating the findings of health services research back into clinical research through prospective cohort studies has the potential to drive medical innovations faster, more effectively and, above all, in a more targeted manner. These must therefore be a central component of cutting-edge oncological research. OBJECTIVE: The aim of the registry is the establishment of clinical cohorts and the provision of a comprehensive, high-quality data set for oncological diseases. METHODS/DESIGN: The registry will prospectively record all patients treated for cancer at Dresden University Hospital (UKD). In addition to the data from the hospital information systems (ORBIS, TDS, GEPADO, etc.), monitoring of health-related quality of life (HRQOL) is to be carried out at regular intervals at the beginning and during the course of treatment. In addition, individual linkage with data from clinical cancer registries and health insurance companies (including AOK PLUS) is planned for a period of five years before and after inclusion. All these data will be merged in a registry database. The selection of variables and measurement time points is closely based on the guidelines for colorectal carcinoma of the international initiative ICHOM (International Consortium for Health Outcomes Measurement). The study management software (STeVe) separates personal identification characteristics (IDAT) and medical data (MDAT) at an early stage. The independent trust centre of the TU Dresden (Treuhandstelle) ensures that no personal data enter the registry database. It is thereby also ensured that the data owners involved (UKD, biobank, health insurance company, cancer registry, patient) only receive the personal data they need for allocation. The MOSAIC software tools recommended by the TMF (Technologie- und Methodenplattform für die vernetzte medizinische Forschung e.V.) are used to manage the pseudonyms. DISCUSSION/CONCLUSION: With the registry, previously missing evidence on the effectiveness, safety and costs of diagnostic and therapeutic measures can be made, taking into account long-term and patient-reported outcomes of routine care. The data potentially allow for the identification of barriers to and facilitators of innovative promising cancer diagnostics and therapies. They also enable generation of scientifically relevant hypotheses in the field of translational and outcomes research.

Artificial Intelligence for context-aware surgical guidance in complex robot-assisted oncological procedures: An exploratory feasibility study.

INTRODUCTION: Complex oncological procedures pose various surgical challenges including dissection in distinct tissue planes and preservation of vulnerable anatomical structures throughout different surgical phases. In rectal surgery, violation of dissection planes increases the risk of local recurrence and autonomous nerve damage resulting in incontinence and sexual dysfunction. This work explores the feasibility of phase recognition and target structure segmentation in robot-assisted rectal resection (RARR) using machine learning. MATERIALS AND METHODS: A total of 57 RARR were recorded and subsets of these were annotated with respect to surgical phases and exact locations of target structures (anatomical structures, tissue types, static structures, and dissection areas). For surgical phase recognition, three machine learning models were trained: LSTM, MSTCN, and Trans-SVNet. Based on pixel-wise annotations of target structures in 9037 images, individual segmentation models based on DeepLabv3 were trained. Model performance was evaluated using F1 score, Intersection-over-Union (IoU), accuracy, precision, recall, and specificity. RESULTS: The best results for phase recognition were achieved with the MSTCN model (F1 score: 0.82 ± 0.01, accuracy: 0.84 ± 0.03). Mean IoUs for target structure segmentation ranged from 0.14 ± 0.22 to 0.80 ± 0.14 for organs and tissue types and from 0.11 ± 0.11 to 0.44 ± 0.30 for dissection areas. Image quality, distorting factors (i.e. blood, smoke), and technical challenges (i.e. lack of depth perception) considerably impacted segmentation performance. CONCLUSION: Machine learning-based phase recognition and segmentation of selected target structures are feasible in RARR. In the future, such functionalities could be integrated into a context-aware surgical guidance system for rectal surgery.

Robotic Esophagectomy Compared With Open Esophagectomy Reduces Sarcopenia within the First Postoperative Year: A Propensity Score-Matched Analysis.

INTRODUCTION: Sarcopenia is a known risk factor for adverse outcomes after esophageal cancer (EC) surgery. Robot-assisted minimally invasive esophagectomy (RAMIE) offers numerous advantages, including reduced morbidity and mortality. However, no evidence exists to date comparing the development of sarcopenia after RAMIE and open esophagectomy (OE). The objective was to evaluate whether the development of sarcopenia within the first postoperative year after esophagectomy is associated with the surgical approach: RAMIE versus OE. METHODS: A total of 168 patients with EC were analyzed who either underwent total robotic or fully open Ivor Lewis esophagectomy in a propensity score-matched analysis. Sarcopenia was assessed using the skeletal muscle index (cm2/m2) and psoas muscle thickness per height (mm/m) on axial computed tomography scans during the first postoperative year; in total 540 computed tomography scans were evaluated. RESULTS: After 1-to-1 propensity score matching for confounders, 67 patients were allocated to RAMIE and OE groups, respectively. Skeletal muscle index in the OE group was significantly lower compared with the RAMIE group at the third (43.2 ± 7.6 cm2/m2 versus 49.1 ± 6.9 cm2/m2, p = 0.001), sixth (42.7 ± 7.8 cm2/m2 versus 51.5 ± 8.2 cm2/m2, p < 0.001) and ninth (43.0 ± 7.0 cm2/m2 versus 49.9 ± 6.6 cm2/m2, p = 0.015) postoperative month. Similar results were recorded for psoas muscle thickness per height. CONCLUSIONS: To our knowledge, this study is the first to suggest a substantial benefit of RAMIE compared with open esophagectomy in terms of postoperative sarcopenia. These results add further evidence to support the implementation of the robotic approach in multimodal therapy of EC.

Selective decontamination of the digestive tract in colorectal surgery reduces anastomotic leakage and costs: a propensity score analysis.

PURPOSE: Anastomotic leakage (AL) and surgical site infection (SSI) account for most postoperative complications in colorectal surgery. The aim of this retrospective trial was to investigate whether perioperative selective decontamination of the digestive tract (SDD) reduces these complications and to provide a cost-effectiveness model for elective colorectal surgery. METHODS: All patients operated between November 2016 and March 2020 were included in our analysis. Patients in the primary cohort (PC) received SDD and those in the historical control cohort (CC) did not receive SDD. In the case of rectal/sigmoid resection, SDD was also applied via a transanally placed Foley catheter (TAFC) for 48 h postoperatively. A propensity score-matched analysis was performed to identify risk factors for AL and SSI. Costs were calculated based on German diagnosis-related group (DRG) fees per case. RESULTS: A total of 308 patients (154 per cohort) with a median age of 62.6 years (IQR 52.5-70.8) were analyzed. AL was observed in ten patients (6.5%) in the PC and 23 patients (14.9%) in the CC (OR 0.380, 95% CI 0.174-0.833; P = 0.016). SSI occurred in 14 patients (9.1%) in the PC and 30 patients in the CC (19.5%), representing a significant reduction in our SSI rate (P = 0.009). The cost-effectiveness analysis showed that SDD is highly effective in saving costs with a number needed to treat of 12 for AL and 10 for SSI. CONCLUSION: SDD significantly reduces the incidence of AL and SSI and saves costs for the general healthcare system.

Influence of the First Wave of the COVID-19 Pandemic on Cancer Care in a German Comprehensive Cancer Center.

Introduction: During the first wave of the COVID-19 pandemic in 2020, the German government implemented legal restrictions to avoid the overloading of intensive care units by patients with COVID-19. The influence of these effects on diagnosis and treatment of cancer in Germany is largely unknown. Methods: To evaluate the effect of the first wave of the COVID-19 pandemic on tumor board presentations in a high-volume tertiary referral center (the German Comprehensive Cancer Center NCT/UCC Dresden), we compared the number of presentations of gastrointestinal tumors stratified by tumor entity, tumor stage, and treatment intention during the pandemic to the respective data from previous years. Results: The number of presentations decreased by 3.2% (95% CI -8.8, 2.7) during the COVID year 2020 compared with the pre-COVID year 2019. During the first shutdown, March-May 2020, the total number of presentations was 9.4% (-18.7, 1) less than during March-May 2019. This decrease was significant for curable cases of esophageal cancer [N = 37, 25.5% (-41.8, -4.4)] and colon cancer [N = 36, 17.5% (-32.6, 1.1)] as well as for all cases of biliary tract cancer [N = 26, 50% (-69.9, -15)] during the first shutdown from March 2020 to May 2020. Conclusion: The impact of the COVID-19 pandemic on the presentation of oncological patients in a CCC in Germany was considerable and should be taken into account when making decisions regarding future pandemics.

Diagnostic performance of 18F-fluorodeoxyglucose-PET/MRI versus MRI alone in the diagnosis of pelvic recurrence of rectal cancer.

PURPOSE: To compare the diagnostic performance of 18F-fluorodeoxyglucose-PET/MRI and MRI in the diagnosis of pelvic recurrence of rectal cancer. METHODS: All PET/MRIs of patients in the follow-up of rectal cancer performed between 2011 and 2018 at our institution were retrospectively reviewed. Recurrence was confirmed/excluded either by histopathology or imaging follow-up (> 4 months). Four groups of readers (groups 1/2: one radiologist each, groups 3/4: one radiologist/one nuclear medicine physician) independently interpreted MRI and PET/MRI. The likelihood of recurrence was scored on a 5-point-scale. Inter-reader agreement, sensitivity, specificity, PPV/NPV and accuracy were assessed. ROC curve analyses were performed. RESULTS: Fourty-one PET/MRIs of 40 patients (mean 61 years ± 10.9; 11 women, 29 men) were included. Sensitivity of PET/MRI in detecting recurrence was 94%, specificity 88%, PPV/NPV 97% and 78%, accuracy 93%. Sensitivity of MRI was 88%, specificity 75%, PPV/NPV 94% and 60%, accuracy 85%. ROC curve analyses showed an AUC of 0.97 for PET/MRI and 0.92 for MRI, but the difference was not statistically significant (p = 0.116). On MRI more cases were scored as equivocal (12% versus 5%). Inter-reader agreement was substantial for PET/MRI and MRI (0.723 and 0.656, respectively). CONCLUSION: 18F-FDG-PET/MRI and MRI are accurate in the diagnosis of locally recurrent rectal cancer. Sensitivity, specificity, PPV, NPV and accuracy are comparable for both modalities, but PET/MRI increases readers' confidence levels and reduces the number of equivocal cases.

Pelvic exenteration for colorectal and non-colorectal cancer: a comparison of perioperative and oncological outcome.

BACKGROUND: Pelvic exenteration (PE) is the only option for long-term cure of advanced cancer originating from different types of tumor or recurrent disease in the lower pelvis. The aim was to show differences between colorectal and non-colorectal cancer in survival and postoperative morbidity. METHODS: Retrospective data of 63 patients treated with total pelvic exenteration between 2013 and 2018 are reported. Pre-, intra-, and postoperative parameters, survival data, and risk factors for complications were analyzed. RESULTS: A total of 57.2% (n = 37) of the patients had colorectal cancer, 22.3% had gynecological malignancies (vulvar (n = 6) or cervical (n = 8) cancer), 11.1% (n = 7) had anal cancer, and 9.5% had other primary tumors. A total of 30.2% (n = 19) underwent PE for a primary tumor and 69.8% (n = 44) for recurrent cancer. The 30-day in-hospital mortality was 0%. Neoadjuvant treatment was administered to 65.1% (n = 41) of the patients and correlated significantly with postoperative complications (odds ratio 4.441; 95% CI: 1.375-14.342, P > 0.05). R0, R1, R2, and Rx resections were achieved in 65.1%, 19%, 1.6%, and 14.3% of the patients, respectively. In patients undergoing R0 resection, 2-year OS and RFS were 73.2% and 52.4%, respectively. Resection status was a significant risk factor for recurrence-free and overall survival (OS) in univariate analysis. Multivariate analysis revealed age (P = 0.021), ASA ≥ 3 (P = 0.005), high blood loss (P = 0.028), low preoperative hemoglobin level (P < 0.001), nodal positivity (P < 0.001), and surgical complications (P = 0.003) as independent risk factors for OS. CONCLUSION: Pelvic exenteration is a procedure with high morbidity rates but remains the only curative option for advanced or recurrent colorectal and non-colorectal cancer in the pelvis.

eHealth Literacy of German Physicians in the Pre-COVID-19 Era: Questionnaire Study.

BACKGROUND: Digitalization is a disruptive technology that changes the way we deliver diagnostic procedures and treatments in medicine. Different stakeholders have varying interests in and expectations of the digitalization of modern medicine. Many recent digital advances in the medical field, such as the implementation of electronic health records, telemedical services, and mobile health apps, are increasingly used by medical professionals and patients. During the current pandemic outbreak of a novel coronavirus-caused respiratory disease (COVID-19), many modern information and communication technologies (ICT) have been used to overcome the physical barriers and limitations caused by government-issued curfews and workforce shortages. Therefore, the COVID-19 pandemic has led to a surge in the usage of modern ICT in medicine. At the same time, the eHealth literacy of physicians working with these technologies has probably not improved since our study. OBJECTIVE: This paper describes a representative cohort of German physicians before the COVID-19 pandemic and their eHealth literacy and attitude towards modern ICT. METHODS: A structured, self-developed questionnaire about user behavior and attitudes towards eHealth applications was administered to a representative cohort of 93 German physicians. RESULTS: Of the 93 German physicians who participated in the study, 97% (90/93) use a mobile phone. Medical apps are used by 42% (39/93). Half of the surveyed physicians (47/93, 50%) use their private mobile phones for official purposes on a daily basis. Telemedicine is part of the daily routine for more than one-third (31/93, 33%) of all participants. More than 80% (76/93, 82%) of the trial participants state that their knowledge regarding the legal aspects and data safety of medical apps and cloud computing is insufficient. CONCLUSIONS: Modern ICT is frequently used and mostly welcomed by German physicians. However, there is a tremendous lack of eHealth literacy and knowledge about the safe and secure implementation of these technologies in routine clinical practice.

First application of intraoperative MRI of the liver during ALPPS procedure for colorectal liver metastases.

PURPOSE: Intraoperative detection of intrahepatic lesions can be demanding. The use of preoperative contrast-enhanced magnetic resonance imaging (MRI) or computer tomography (CT) combined with intraoperative ultrasound of the liver is state of the art. Near totally regressed colorectal liver metastases (CRLM) after neoadjuvant chemotherapy or nodules in severely altered liver tissue as steatosis or cirrhosis are often hard to detect during the operative procedure. Especially differentiation between benign atypical nodules and malignant tumors can be very difficult. The intraoperative use of contrast-enhanced ultrasound or intraoperative navigation are helpful tools. However, both methods show relevant limitations. The use of intraoperative MRI (ioMRI) can overcome this problem. Relevant structures can be marked within the operative site or immediate control of complete tumor resection can be achieved. This might allow immediate surgical optimization in case of failure. METHODS: We report the intraoperative application of ioMRI in a case of a 61-year-old male patient suffering from rectal cancer with 10 synchronous bilobar CRLM who was treated stepwise by multimodal treatment and staged hepatectomy. Intraoperative contrast-enhanced MRI of the liver was used during completion procedure of an extended right hemihepatectomy performed as "Associating Liver Partition and Portal vein Ligation for Staged hepatectomy (ALPPS)". RESULTS: ioMRI provided excellent images and showed absence of liver metastases in the liver remnant. Procedure of ioMRI was safe, fast and feasible. CONCLUSION: To the best of our knowledge, we describe the first case of intraoperative application of a contrast-enhanced MRI during open liver surgery at the University Hospital of Dresden.

State of the Art - Rectal Cancer Surgery.

BACKGROUND: In an aging society, the incidence and relevance of rectal cancer as one of the most frequent gastrointestinal cancers gains in importance. Excellent surgery and up-to-date multimodal treatments are essential for adequate oncological results and good quality of life. SUMMARY: In this review, we describe modern developments in rectal cancer surgery and its embedment in modern multimodal therapy concepts. KEY MESSAGE: Distinguished interdisciplinary cooperation combined with an outstanding surgical expertise is the basic requirement for an optimal treatment of rectal cancer. Thus, high standards of oncological outcome and patient's quality of life can be achieved.

Comparison of three classifications for lymph node evaluation in patients undergoing total mesorectal excision for rectal cancer.

PURPOSE: The present study compared the prognostic value of the lymph node ratio (LNR) and the 6th and the 7th TNM edition as three different lymph node classifications for rectal cancer patients. METHODS: A total of 630 patients who underwent total mesorectal excision for primary rectal cancer between October 2001 and December 2007 were included. Prognostic factors of overall survival were analyzed using Cox proportional hazards models. RESULTS: The median follow-up was 36.1 months and the 5-year overall survival rate was 70.3 ± 4.7%. The median number of lymph nodes was 15.0 (12.0-19.0). All three lymph node evaluations correlated with survival (p < 0.0001). The assessment of nodal status in the 7th TNM edition enabled further prognostic stratification. The prognostic value of the three classifications were independent of neoadjuvant therapy and lymph node count. On multivariate analyses, the N2 stage of the 6th TNM edition (Hazard ratio 2.08; 95% confidence interval 1.21-3.58) and the N2b stage of the 7th TNM edition (2.18; 1.17-4.07) correlated with poor survival. A LNR of 0.42-0.69 was also associated with unfavorable prognosis (2.97; 1.46-6.03), as was an LNR > 0.69 (2.51; 1.04-6.05). The LNR did not provide prognostic information in addition to the N stage of the TNM classifications. CONCLUSIONS: The evaluated lymph node classifications were of comparable prognostic utility in patients with rectal cancer. The LNR did not provide prognostic information in addition to the N stage of the TNM classifications.

Inhibition of Six1 affects tumour invasion and the expression of cancer stem cell markers in pancreatic cancer.

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) and cancer stem cells (CSC) contribute to tumour progression and metastasis. Assessment of transcription factors involved in these two mechanisms can help to identify new targets for an oncological therapy. In this study, we focused on the evaluation of the transcription factor Six1 (Sine oculis 1). This protein is involved in embryologic development and its contribution to carcinogenesis has been described in several studies. METHODS: Immunohistochemistry against Six1 was performed on a tissue microarray containing specimens of primary pancreatic ductal adenocarcinomas (PDAC) of 139 patients. Nuclear and cytoplasmic expression was evaluated and correlated to histopathological parameters. Expression of Six1 was inhibited transiently by siRNA in Panc1 and BxPc3 cells and stably by shRNA in Panc1 cells. Expression analysis of CDH1 and Vimentin mRNA was performed and cell motility was tested in a migration assay. Panc1 cells transfected with Six1 shRNA or scrambled shRNA were injected subcutaneously into nude mice. Tumour growth was observed for four weeks. Afterwards, tumours were stained against Six1, CD24 and CD44. RESULTS: Six1 was overexpressed in the cytoplasm and cellular nuclei in malignant tissues (p < 0.0001). No correlation to histopathological parameters could be detected. Six1 down-regulation decreased pancreatic cancer cell motility in vitro. CDH1 and vimentin expression was decreased after inhibition of the expression of Six1. Pancreatic tumours with impaired expression of Six1 showed significantly delayed growth and displayed loss of the CD24+/CD44+ phenotype. CONCLUSION: We show that Six1 is overexpressed in human PDAC and that its inhibition results in a decreased tumour progression in vitro and in vivo. Therefore, targeting Six1 might be a novel therapeutic approach in patients with pancreatic cancer.

Impact of Bevacizumab on parenchymal damage and functional recovery of the liver in patients with colorectal liver metastases.

BACKGROUND: Little is known about the safety of the anti-VEGF antibody bevacizumab in patients undergoing resection for colorectal liver metastases (CLM). This meta-analysis evaluates the impact of bevacizumab on parenchymal damage and functional recovery in patients undergoing resection for CLM. METHODS: The Medline, Embase and Cochrane Library were systematically searched for studies on preoperative chemotherapy with and without bevacizumab prior to resection of CLM. Studies that reported histological and/or clinical outcomes were eligible for inclusion. Meta-analyses were performed using a random effects model. RESULTS: A total of 18 studies with a total sample size of 2430 patients (1050 patients with bevacizumab) were found. Meta-analyses showed a significant reduction in sinusoidal obstruction syndrome (SOS) (Odds ratio 0.50 [95% confidence interval 0.37, 0.67]; p < 0.001; I(2) = 0%) and hepatic fibrosis (0.61 [0.4, 0.86]; p = 0.004; I(2) = 7%) after preoperative chemotherapy with bevacizumab. The reduced incidence of posthepatectomy liver failure in patients with bevacizumab treatment just failed to reach statistical significance (0.61 [0.34, 1.07]; p = 0.08 I(2) = 6%). While there was no difference in perioperative morbidity and mortality, the incidence of wound complications was significantly increased in patients who received bevacizumab (1.81 [1.12, 2.91]; p = 0.02 I(2) = 4%). CONCLUSIONS: The combination of bevacizumab with cytotoxic chemotherapy is safe but increases the incidence of wound complications after resection of CLM. The reduction of SOS and hepatic fibrosis warrant further investigation and may explain the inverse association of bevacizumab administration and posthepatectomy liver failure.

New Wnt/ß-catenin target genes promote experimental metastasis and migration of colorectal cancer cells through different signals.

OBJECTIVES: We have previously identified a 115-gene signature that characterises the metastatic potential of human primary colon cancers. The signature included the canonical Wnt target gene BAMBI, which promoted experimental metastasis in mice. Here, we identified three new direct Wnt target genes from the signature, and studied their functions in epithelial-mesenchymal transition (EMT), cell migration and experimental metastasis. DESIGN: We examined experimental liver metastases following injection of selected tumour cells into spleens of NOD/SCID mice. Molecular and cellular techniques were used to identify direct transcription target genes of Wnt/ß-catenin signals. Microarray analyses and experiments that interfered with cell migration through inhibitors were performed to characterise downstream signalling systems. RESULTS: Three new genes from the colorectal cancer (CRC) metastasis signature, BOP1, CKS2 and NFIL3, were identified as direct transcription targets of ß-catenin/TCF4. Overexpression and knocking down of these genes in CRC cells promoted and inhibited, respectively, experimental metastasis in mice, EMT and cell motility in culture. Cell migration was repressed by interfering with distinct signalling systems through inhibitors of PI3K, JNK, p38 mitogen-activated protein kinase and/or mTOR. Gene expression profiling identified a series of migration-promoting genes, which were induced by BOP1, CKS2 and NFIL3, and could be repressed by inhibitors that are specific to these pathways. CONCLUSIONS: We identified new direct Wnt/ß-catenin target genes, BOP1, CKS2 and NFIL3, which induced EMT, cell migration and experimental metastasis of CRC cells. These genes crosstalk with different downstream signalling systems, and activate migration-promoting genes. These pathways and downstream genes may serve as therapeutic targets in the treatment of CRC metastasis.

Free intraperitoneal tumor cells and outcome in gastric cancer patients: a systematic review and meta-analysis.

PURPOSE: Despite continuously improving therapies, gastric cancer still shows poor survival in locally advanced stages with local recurrence rates of up to 50% and peritoneal recurrence rates of 17% after curative surgery. We performed a systematic review with meta-analyses to clarify whether positive intraperitoneal cytology (IPC) indicates a high risk of disease recurrence and poor overall survival in gastric cancer. METHODS: Multiple databases were searched in December 2014 to identify studies on the prognostic significance of positive intraperitoneal cytology in gastric cancer, including: Medline, Biosis, Science Citation Index, Embase, CCMed and publisher databases. Hazard ratios (HR) and associated 95% confidence intervals (CI) were extracted from the identified studies. A meta-analysis was performed using a random-effects model on overall survival, disease-free survival and peritoneal recurrence free survival. RESULTS: A total of 64 studies with a cumulative sample size of 12,883 patients were included. Cytology, quantitative real time polymerase chain reaction (PCR) or both were performed in 35; 21 and 8 studies, respectively. Meta analyses revealed free intraperitoneal tumor cells (FITC) to be associated with poor overall survival in univariate (HR 3.27; 95% CI 2.82 - 3.78]) and multivariate (HR 2.45; 95% CI 2.04 - 2.94) analysis and poor peritoneal recurrence free survival in univariate (4.15; 95% CI 3.10 - 5.57) and multivariate (3.09; 95% CI 2.02 - 4.71) analysis. Subgroup analysis showed this effect to be independent of the detection method, Western or Asian origin or the time of publication. CONCLUSIONS: FITC oder positive peritoneal cytology is associated with poor survival and increased peritoneal recurrence in gastric cancer.

Overexpression of ZEB2 at the invasion front of colorectal cancer is an independent prognostic marker and regulates tumor invasion in vitro.

PURPOSE: Epithelial-to-mesenchymal transition (EMT) plays a pivotal role in tumor invasion and dissemination. EMT occurs predominantly at the tumor edge where it is induced by cytokines, the extracellular matrix environment, or hypoxia. In the tumor cell, it is further mediated by several transcription factors and microRNAs. The aim of this study was to explore the expression of EMT-associated genes at the invasive front in colorectal cancer and to evaluate their prognostic significance. EXPERIMENTAL DESIGN: We evaluated the expression of 13 EMT-associated genes at the invasion front of 30 colorectal liver metastases by quantitative real-time PCR. Immunostaining against zinc finger E-box-binding homeobox 2 (ZEB2) was carried out on 175 primary colorectal cancer specimens and 30 colorectal liver metastases and correlated to clinical and histopathologic data. DLD-1 cells were transfected with siRNA and subjected to migration and invasion assays. RESULTS: Gene expression analysis and immunohistochemistry showed an upregulation of ZEB2 at the invasion front in primary colorectal cancer and liver metastases. Overexpression of ZEB2 at the invasion front correlated significantly with tumor stage in primary colorectal cancer. Moreover, univariate and multivariate analysis revealed overexpression of ZEB2 at the invasion front as an independent prognostic marker for cancer-specific survival. Downregulation of ZEB2 by siRNA decreased the migration and invasion capacity of DLD-1 cells in vitro. CONCLUSIONS: Overexpression of ZEB2 at the invasion front correlates with tumor progression and predicts cancer-specific survival in primary colorectal cancer. Therefore, ZEB2 may be interesting as biomarker and potential target for treatment of colorectal cancer.

An RNA interference phenotypic screen identifies a role for FGF signals in colon cancer progression.

In tumor cells, stepwise oncogenic deregulation of signaling cascades induces alterations of cellular morphology and promotes the acquisition of malignant traits. Here, we identified a set of 21 genes, including FGF9, as determinants of tumor cell morphology by an RNA interference phenotypic screen in SW480 colon cancer cells. Using a panel of small molecular inhibitors, we subsequently established phenotypic effects, downstream signaling cascades, and associated gene expression signatures of FGF receptor signals. We found that inhibition of FGF signals induces epithelial cell adhesion and loss of motility in colon cancer cells. These effects are mediated via the mitogen-activated protein kinase (MAPK) and Rho GTPase cascades. In agreement with these findings, inhibition of the MEK1/2 or JNK cascades, but not of the PI3K-AKT signaling axis also induced epithelial cell morphology. Finally, we found that expression of FGF9 was strong in a subset of advanced colon cancers, and overexpression negatively correlated with patients' survival. Our functional and expression analyses suggest that FGF receptor signals can contribute to colon cancer progression.