The role of neoadjuvant and adjuvant treatment for adenocarcinoma of the upper gastrointestinal tract

Both locally advanced adenocarcinoma of the stomach and gastro-esophageal junction are associated with poor prognosis due to the lack of effective treatment. Recently multimodal treatment consisting of neoadjuvant chemotherapy in combination with radiotherapy is reported to improve survival when compared to surgery alone. Neoadjuvant therapy in these locally advanced tumors allows for early tumor responses and the extent of tumor regression that can be achieved is considered a significant prognostic factor. This, in turn, increases the resectability of these tumors. Also due to the high frequency of lymph node metastasis, patients with locally advanced adenocarcinoma should undergo a D2 lymphadenectomy. Postoperative chemoradiation and perioperative chemotherapy have been studied in gastric adenocarcinomas and showed a survival benefit. However, the surgical techniques used in these trials are no longer considered to be standard by today's surgical practice. In addition, there are no standard recommendations for adjuvant chemotherapy or chemoradiation after R0 resection and adequate lymph node dissection

Evaluation of the tissue toxicity of antiseptics by the hen's egg test on the chorioallantoic membrane (HETCAM)

<p>Abstract</p> <p>Background</p> <p>Antiseptics are frequently used for the prophylaxis and treatment of local infections of chronic wounds. Whereas local antiseptics in general have a positive effect on wound healing an uncritical use may impair wound healing due to toxic side effects.</p> <p>Objective</p> <p>We sought to assess the vascular irritation potential of different antiseptic solutions and ointments commonly used for short and long term application as a measure of tissue toxicity.</p> <p>Method</p> <p>The vascular irritation was evaluated by the hen's egg test (HET) on the chorioallantoic membrane (CAM). The effects on the vessels of a mucous membrane were directly assessed by stereomicroscopic observation in vivo.</p> <p>Results</p> <p>Severe CAM irritation was observed after short-term applications of 1% octenidin-2HCl (Octeni sept™), 72% isopropanol (Cutasept™), 0.35% chloroxylenol (Dettol™) and 10% PVP-I ointment (Betaisodona™). Medium irritations were observed for 10% PVP-I solution (Betaisodona™), 3% lysosomal PVP-I ointment (Repithel™), 1.8% cadexomer-iodine ointment (Iodosorb™) and 1% cadexomer-iodine pellets (Iodosorb™). Finally, slight irritations were observed for 1% PVP-I solution (Betaisodona™), 0.1% polyhexanid plus betain (Prontosan™) and 1% silver-sulfadiazine ointment (Flammazine™), whereas 0.04% polyhexanid solution (Lavanid™), washings from sterile maggots of Lucilia sericata and filtrated enzymes from Clostridium histolyticum (Iruxol-N™) showed no effects of irritation. In the long-term approaches, no vascular irritations were found for polyhexanid, washings from Lucilia sericata and enzyme filtrations from Clostridium histolyticum.</p> <p>Conclusion</p> <p>The vascular injuries caused by the studied antiseptics are an indirect indicator of their tissue toxicity. Strikingly, even therapeutic substances, which have been regarded as safe in their application for the treatment of chronic wounds in clinical studies, showed severe irritations on the CAM. We suggest that agents with no or low irritation potential on the CAM should be preferred in the clinical practice in order to obtain optimal results.</p

MicroRNA-199b-5p Impairs Cancer Stem Cells through Negative Regulation of HES1 in Medulloblastoma

BACKGROUND: Through negative regulation of gene expression, microRNAs (miRNAs) can function in cancers as oncosuppressors, and they can show altered expression in various tumor types. Here we have investigated medulloblastoma tumors (MBs), which arise from an early impairment of developmental processes in the cerebellum, where Notch signaling is involved in many cell-fate-determining stages. MBs occur bimodally, with the peak incidence seen between 3-4 years and 8-9 years of age, although it can also occur in adults. Notch regulates a subset of the MB cells that have stem-cell-like properties and can promote tumor growth. On the basis of this evidence, we hypothesized that miRNAs targeting the Notch pathway can regulated these phenomena, and can be used in anti-cancer therapies. METHODOLOGY/PRINCIPAL FINDINGS: In a screening of MB cell lines, the miRNA miR-199b-5p was seen to be a regulator of the Notch pathway through its targeting of the transcription factor HES1. Down-regulation of HES1 expression by miR-199b-5p negatively regulates the proliferation rate and anchorage-independent growth of MB cells. MiR-199b-5p over-expression blocks expression of several cancer stem-cell genes, impairs the engrafting potential of MB cells in the cerebellum of athymic/nude mice, and of particular interest, decreases the MB stem-cell-like (CD133+) subpopulation of cells. In our analysis of 61 patients with MB, the expression of miR-199b-5p in the non-metastatic cases was significantly higher than in the metastatic cases (P = 0.001). Correlation with survival for these patients with high levels of miR-199b expression showed a positive trend to better overall survival than for the low-expressing patients. These data showing the down-regulation of miR-199b-5p in metastatic MBs suggest a potential silencing mechanism through epigenetic or genetic alterations. Upon induction of de-methylation using 5-aza-deoxycytidine, lower miR-199b-5p expression was seen in a panel of MB cell lines, supported an epigenetic mechanism of regulation. Furthermore, two cell lines (Med8a and UW228) showed significant up-regulation of miR-199b-5p upon treatment. Infection with MB cells in an induced xenograft model in the mouse cerebellum and the use of an adenovirus carrying miR-199b-5p indicate a clinical benefit through this negative influence of miR-199b-5p on tumor growth and on the subset of MB stem-cell-like cells, providing further proof of concept. CONCLUSIONS/SIGNIFICANCE: Despite advances in our understanding of the pathogenesis of MB, one-third of these patients remain incurable and current treatments can significantly damage long-term survivors. Here we show that miR-199b-5p expression correlates with metastasis spread, identifying a new molecular marker for a poor-risk class in patients with MB. We further show that in a xenograft model, MB tumor burden can be reduced, indicating the use of miR199b-5p as an adjuvant therapy after surgery, in combination with radiation and chemotherapy, for the improvement of anti-cancer MB therapies and patient quality of life. To date, this is the first report that expression of a miRNA can deplete the tumor stem cells, indicating an interesting therapeutic approach for the targeting of these cells in brain tumors

Trimodal therapy in squamous cell carcinoma of the esophagus

<p>Abstract</p> <p>Patients with ESCC (squamous cell carcinoma of the esophagus) are most commonly diagnosed with locally advanced tumor stages. Early metastatic disease and late diagnosis are common reasons responsible for this tumor's poor clinical outcome. The prognosis of esophageal cancer is very poor because patients usually do not have symptoms in early disease stages. Squamous cell carcinoma of the esophagus frequently complicates patients with multiple co-morbidities and these patients often require interdisciplinary diagnosis and treatment procedures. At present time, neoadjuvant radiation therapy and chemotherapy followed by surgery are regarded as the international standard of care. Meta-analyses have confirmed that this approach provides the patient with better local tumor control and an increased overall survival rate. It is recommended that patients with positive tumor response to neoadjuvant therapy and who are poor surgical candidates should consider definitive radiochemotherapy without surgery as a treatment option. In future, EGFR antibodies may also be administered to patients during therapy to improve the current treatment effectiveness. Positron-emission tomography proves to be an early response-imaging tool used to evaluate the effect of the neoadjuvant therapy and could be used as a predictive factor for the survival rate in ESCC. The percentage proportions of residual tumor cells in the histopathological analyses represent a gold standard for evaluating the response rate to radiochemotherapy. In the future, early response evaluation and molecular biological tests could be important diagnostic tools in influencing the treatment decisions of ESCC patients.</p

Do insulin-like growth factor associated proteins qualify as a tumor marker? results of a prospective study in 163 cancer patients*

Abstract Objective Insulin-like growth factor (IGF)-1, -2 and Insulin like growth factor binding proteins (IGFBP) are involved in the proliferation and differentiation of cells. It has never been evaluated, if the IGF-system can serve as a tumor marker in neoplasms. Methods In our prospective study 163 patients with colorectal cancer (22), prostate cancer (21), head and neck tumors (17), lymphomas (20), lung cancer (34) and other entities (49) were analysed for their IGF and IGFBP serum levels at the beginning and the end of radiotherapy and compared to 13 healthy people. Subgroups of patients with local tumor disease versus metastatic disease, primary and recurrent therapy and curative versus palliative therapy were compared. Results The serum levels of IGF-2 were significantly elevated in patients with prostate and colorectal cancer. However, sensitivity and specificity were only 70%. IGFBP-2 serum levels were elevated in patients with head and neck tumors. Again sensitivity and specificity were only 73%. A difference between local disease and metastatic disease could not be found. A difference between IGF serum levels before and after radiotherapy could not be detected. Conclusion The IGF-system cannot serve as a new tumor marker. The detected differences are very small, sensitivity and specificity are too low. IGF measurement is not useful for the evaluation of the success of radiotherapy in malignancies.</p

WNT/β-catenin pathway activation in Myc immortalised cerebellar progenitor cells inhibits neuronal differentiation and generates tumours resembling medulloblastoma

Background: Medulloblastoma is the most common malignant childhood brain tumour. Aberrant activation of the WNT/β-catenin pathway occurs in approximately 25% of medulloblastomas. However, its role in medulloblastoma pathogenesis is not understood. Methods: We have developed a model of WNT/β-catenin pathway-activated medulloblastoma. Pathway activation was induced in a Myc immortalised cerebellar progenitor cell line through stable expression of Wnt1. In vitro and in vivo analysis was undertaken to understand the effect of pathway activation and identify the potential cell of origin. Results: Tumours that histologically resembled classical medulloblastoma formed in vivo using cells overexpressing Wnt1, but not with the control cell line. Wnt1 overexpression inhibited neuronal differentiation in vitro, suggesting WNT/β-catenin pathway activation prevents cells terminally differentiating, maintaining them in a more ‘stem-like’ state. Analysis of cerebellar progenitor cell markers demonstrated the cell line resembled cells from the cerebellar ventricular zone. conclusion: We have developed a cell line with the means of orthotopically modelling WNT/β-catenin pathway-activated medulloblastoma. We provide evidence of the role pathway activation is playing in tumour pathogenesis and suggest medulloblastomas can arise from cells other than granule cell progenitors. This cell line is a valuable resource to further understand the role of pathway activation in tumorigenesis and for investigation of targeted therapies