Met expression is an independent prognostic risk factor in patients with oesophageal adenocarcinoma

Oesophageal adenocarcinoma is an aggressive malignancy with propensity for early lymphatic and haematogenous dissemination. Since conventional TNM staging does not provide accurate prognostic information, novel molecular prognostic markers and potential therapeutic targets are subject of intense research. The aim of the present study was to study the prognostic significance of Met, the hepatic growth factor ( HGF) receptor and a possible target for therapy in comparison to cyclooxygenase- 2 ( COX- 2). Tumour sections from 145 consecutive patients undergoing intentionally curative surgery for oesophageal adenocarcinoma were immunohistochemically analysed for Met and COX- 2 expression. Clinicopathological data were prospectively collected for all patients. Patients with high Met expression had significantly reduced overall and disease- specific 5- year survival rates ( P <= 0.001 and P <= 0.001, respectively) and were more likely to develop distant metastases ( P = 0.002) and local recurrences ( P =0.004) compared to patients with low Met expression. High COX- 2 expression tended to be correlated with poor long- term survival but this did not reach statistical significance. Expression of Met was recognised as a significant and independent prognostic factor by stage- specific analysis and multivariate analysis ( relative risk 2.3; 95% CI 1.3 - 4.1). These findings support the importance of Met in oesophageal adenocarcinoma and support the concept of Met tyrosine kinase inhibition as ( neo-) adjuvant treatment

COLOR III: a multicentre randomised clinical trial comparing transanal TME versus laparoscopic TME for mid and low rectal cancer

Total mesorectal excision (TME) is an essential component of surgical management of rectal cancer. Both open and laparoscopic TME have been proven to be oncologically safe. However, it remains a challenge to achieve complete TME with clear circumferential resections margin (CRM) with the conventional transabdominal approach, particularly in mid and low rectal tumours. Transanal TME (TaTME) was developed to improve oncological and functional outcomes of patients with mid and low rectal cancer.An international, multicentre, superiority, randomised trial was designed to compare TaTME and conventional laparoscopic TME as the surgical treatment of mid and low rectal carcinomas. The primary endpoint is involved CRM. Secondary endpoints include completeness of mesorectum, residual mesorectum, morbidity and mortality, local recurrence, disease-free and overall survival, percentage of sphincter-saving procedures, functional outcome and quality of life. A Quality Assurance Protocol including centralised MRI review, histopathology re-evaluation, standardisation of surgical techniques, and monitoring and assessment of surgical quality will be conducted.The difference in involvement of CRM between the two treatment strategies is thought to be in favour of the TaTME. TaTME is therefore expected to be superior to laparoscopic TME in terms of oncological outcomes in case of mid and low rectal carcinomas

Met expression is an independent prognostic risk factor in patients with oesophageal adenocarcinoma

Oesophageal adenocarcinoma is an aggressive malignancy with propensity for early lymphatic and haematogenous dissemination. Since conventional TNM staging does not provide accurate prognostic information, novel molecular prognostic markers and potential therapeutic targets are subject of intense research. The aim of the present study was to study the prognostic significance of Met, the hepatic growth factor (HGF) receptor and a possible target for therapy in comparison to cyclooxygenase-2 (COX-2). Tumour sections from 145 consecutive patients undergoing intentionally curative surgery for oesophageal adenocarcinoma were immunohistochemically analysed for Met and COX-2 expression. Clinicopathological data were prospectively collected for all patients. Patients with high Met expression had significantly reduced overall and disease-specific 5-year survival rates (P⩽0.001 and P⩽0.001, respectively) and were more likely to develop distant metastases (P=0.002) and local recurrences (P=0.004) compared to patients with low Met expression. High COX-2 expression tended to be correlated with poor long-term survival but this did not reach statistical significance. Expression of Met was recognised as a significant and independent prognostic factor by stage-specific analysis and multivariate analysis (relative risk=2.3; 95% CI=1.3–4.1). These findings support the importance of Met in oesophageal adenocarcinoma and support the concept of Met tyrosine kinase inhibition as (neo-) adjuvant treatment

Silymarin Targets β-Catenin Signaling in Blocking Migration/Invasion of Human Melanoma Cells

Metastatic melanoma is a leading cause of death from skin diseases, and is often associated with activation of Wnt/β-catenin signaling pathway. We have examined the inhibitory effect of silymarin, a plant flavanoid from Silybum marianum, on cell migration of metastasis-specific human melanoma cell lines (A375 and Hs294t) and assessed whether Wnt/β-catenin signaling is the target of silymarin. Using an in vitro invasion assay, we found that treatment of human melanoma cell lines with silymarin resulted in concentration-dependent inhibition of cell migration, which was associated with accumulation of cytosolic β-catenin, while reducing the nuclear accumulation of β-catenin (i.e., β-catenin inactivation) and reducing the levels of matrix metalloproteinase (MMP) -2 and MMP-9 which are the down-stream targets of β-catenin. Silymarin enhanced: (i) the levels of casein kinase 1α, glycogen synthase kinase-3β and phosphorylated-β-catenin on critical residues Ser45, Ser33/37 and Thr41, and (ii) the binding of β-transducin repeat-containing proteins (β-TrCP) with phospho forms of β-catenin in melanoma cells. These events play important roles in degradation or inactivation of β-catenin. To verify whether β-catenin is a potent molecular target of silymarin, the effect of silymarin was determined on β-catenin-activated (Mel 1241) and β-catenin-inactivated (Mel 1011) melanoma cells. Treatment of Mel 1241 cells with silymarin or FH535, an inhibitor of Wnt/β-catenin pathway, significantly inhibited cell migration of Mel 1241 cells, which was associated with the elevated levels of casein kinase 1α and glycogen synthase kinase-3β, and decreased accumulation of nuclear β-catenin and inhibition of MMP-2 and MMP-9 levels. However, this effect of silymarin and FH535 was not found in Mel 1011 melanoma cells. These results indicate for the first time that silymarin inhibits melanoma cell migration by targeting β-catenin signaling pathway

Nitric Oxide (NO) and Cyclooxygenase-2 (COX-2) Cross-Talk in Co-Cultures of Tumor Spheroids with Normal Cells

Cyclooxygenases (COX), prostaglandin E2 (PGE2) and nitric oxide (NO) are believed to be some of the most important factors related to colon cancer growth and metastasis. In this study, we aimed to investigate the associations between COX-2, PGE2 and NO in co-cultures of human colon cancer spheroids obtained from different tumor grades with normal human colonic epithelium and myofibroblast monolayers. L-arginine (2 mM), a substrate for nitric oxide synthases (NOS), decreased COX-2 and PGE2 levels, while NG-nitro-L-arginine methyl ester (L-NAME) (2 mM), a NOS inhibitor, had no influence on COX-2 and PGE2 levels but limited tumor cell motility. NS398 (75 μM), a selective COX-2 inhibitor, had no significant influence on NO level but decreased motility of tumor cells. COX-2, PGE2 and NO levels depended on the tumor grade of the cells, being the highest in Duke’s stage III colon carcinoma. Summing up, we showed that addition of L-arginine at doses which did not stimulate NO level caused a significant decrease in COX-2 and PGE2 amounts in co-cultures of colon tumor spheroids with normal epithelial cells and myofibroblasts. Any imbalances in NO level caused by exogenous factors influence COX-2 and PGE2 amounts depending on the kind of cells, their reciprocal interactions and the local microenvironmental conditions. The knowledge of these effects may be useful in limiting colon carcinoma progression and invasion

RNA interference as a key to knockdown overexpressed cyclooxygenase-2 gene in tumour cells

Silencing those genes that are overexpressed in cancer and contribute to the survival and progression of tumour cells is the aim of several researches. Cyclooxygenase-2 (COX-2) is one of the most intensively studied genes since it is overexpressed in most tumours, mainly in colon cancer. The use of specific COX-2 inhibitors to treat colon cancer has generated great enthusiasm. Yet, the side effects of some inhibitors emerging during long-term treatment have caused much concern. Genes silencing by RNA interference (RNAi) has led to new directions in the field of experimental oncology. In this study, we detected sequences directed against COX-2 mRNA, that potently downregulate COX-2 gene expression and inhibit phorbol 12-myristate 13-acetate-induced angiogenesis in vitro in a specific, nontoxic manner. Moreover, we found that the insertion of a specific cassette carrying anti-COX-2 short hairpin RNA sequence into a viral vector (pSUPER.retro) greatly increased silencing potency in a colon cancer cell line (HT29) without activating any interferon response. Phenotypically, COX-2 deficient HT29 cells showed a significant impairment of their in vitro malignant behaviour. Thus, the retroviral approach enhancing COX-2 knockdown, mediated by RNAi, proved to be an useful tool to better understand the role of COX-2 in colon cancer. Furthermore, the higher infection efficiency we observed in tumour cells, if compared to normal endothelial cells, may disclose the possibility to specifically treat tumour cells without impairing endothelial COX-2 activity

Perioperative strategy in colonic surgery; LAparoscopy and/or FAst track multimodal management versus standard care (LAFA trial)

BACKGROUND: Recent developments in large bowel surgery are the introduction of laparoscopic surgery and the implementation of multimodal fast track recovery programs. Both focus on a faster recovery and shorter hospital stay. The randomized controlled multicenter LAFA-trial (LAparoscopy and/or FAst track multimodal management versus standard care) was conceived to determine whether laparoscopic surgery, fast track perioperative care or a combination of both is to be preferred over open surgery with standard care in patients having segmental colectomy for malignant disease. METHODS/DESIGN: The LAFA-trial is a double blinded, multicenter trial with a 2 × 2 balanced factorial design. Patients eligible for segmental colectomy for malignant colorectal disease i.e. right and left colectomy and anterior resection will be randomized to either open or laparoscopic colectomy, and to either standard care or the fast track program. This factorial design produces four treatment groups; open colectomy with standard care (a), open colectomy with fast track program (b), laparoscopic colectomy with standard care (c), and laparoscopic surgery with fast track program (d). Primary outcome parameter is postoperative hospital length of stay including readmission within 30 days. Secondary outcome parameters are quality of life two and four weeks after surgery, overall hospital costs, morbidity, patient satisfaction and readmission rate. Based on a mean postoperative hospital stay of 9 +/- 2.5 days a group size of 400 patients (100 each arm) can reliably detect a minimum difference of 1 day between the four arms (alfa = 0.95, beta = 0.8). With 100 patients in each arm a difference of 10% in subscales of the Short Form 36 (SF-36) questionnaire and social functioning can be detected. DISCUSSION: The LAFA-trial is a randomized controlled multicenter trial that will provide evidence on the merits of fast track perioperative care and laparoscopic colorectal surgery in patients having segmental colectomy for malignant disease

A Systematic Screen for Micro-RNAs Regulating the Canonical Wnt Pathway

MicroRNAs (miRs) and the canonical Wnt pathway are known to be dysregulated in human cancers and play key roles during cancer initiation and progression. To identify miRs that can modulate the activity of the Wnt pathway we performed a cell-based overexpression screen of 470 miRs in human HEK293 cells. We identified 38 candidate miRs that either activate or repress the canonical Wnt pathway. A literature survey of all verified candidate miRs revealed that the Wnt-repressing miRs tend to be anti-oncomiRs and down-regulated in cancers while Wnt-activating miRs tend to be oncomiRs and upregulated during tumorigenesis. Epistasis-based functional validation of three candidate miRs, miR-1, miR-25 and miR-613, confirmed their inhibitory role in repressing the Wnt pathway and suggest that while miR-25 may function at the level of â-catenin (β-cat), miR-1 and miR-613 act upstream of β-cat. Both miR-25 and miR-1 inhibit cell proliferation and viability during selection of human colon cancer cell lines that exhibit dysregulated Wnt signaling. Finally, transduction of miR-1 expressing lentiviruses into primary mammary organoids derived from Conductin-lacZ mice significantly reduced the expression of the Wnt-sensitive β-gal reporter. In summary, these findings suggest the potential use of Wnt-modulating miRs as diagnostic and therapeutic tools in Wnt-dependent diseases, such as cancer