Phosphodiesterase type 5 inhibitors enhance chemotherapy in preclinical models of esophageal adenocarcinoma by targeting cancer-associated fibroblasts.

The chemotherapy resistance of esophageal adenocarcinomas (EACs) is underpinned by cancer cell extrinsic mechanisms of the tumor microenvironment (TME). We demonstrate that, by targeting the tumor-promoting functions of the predominant TME cell type, cancer-associated fibroblasts (CAFs) with phosphodiesterase type 5 inhibitors (PDE5i), we can enhance the efficacy of standard-of-care chemotherapy. In ex vivo conditions, PDE5i prevent the transdifferentiation of normal fibroblasts to CAF and abolish the tumor-promoting function of established EAC CAFs. Using shotgun proteomics and single-cell RNA-seq, we reveal PDE5i-specific regulation of pathways related to fibroblast activation and tumor promotion. Finally, we confirm the efficacy of PDE5i in combination with chemotherapy in close-to-patient and in vivo PDX-based model systems. These findings demonstrate that CAFs drive chemotherapy resistance in EACs and can be targeted by repurposing PDE5i, a safe and well-tolerated class of drug administered to millions of patients world-wide to treat erectile dysfunction.

The management and long-term outcomes of endoscopic and surgical treatment of early esophageal adenocarcinoma.

Endoscopic resection (ER) for early (pT1) esophageal adenocarcinoma can be justified if the rate of coexisting lymph node (LN) metastasis is less than the mortality rate from esophagectomy. This study examines endoscopic and surgical outcomes, histological assessment of submucosal (sm) disease, factors influencing LN metastasis, and the safety of treating pT1b disease endoscopically. Histopathological reexamination recorded thickness, width and depth of sm invasion, grade, presence of lymphovascular invasion (LVI), resection margin status and tumor stage. Multivariate analysis was employed to evaluate the factors influencing survival and LN metastasis. Rate of LN metastasis for pT1 low-risk (LR: sm invasion < 500 µm, G1-2, no LVI) or high-risk (HR: sm invasion >500 µm, G3-4 or LVI) disease were analyzed. Ninety three patients underwent ER and 96 underwent esophagectomy. We demonstrate conflicting histological methods of sm disease reporting, which may explain the difference in LN metastasis rate between reported surgical & endoscopic series. Multivariate analysis confirmed age, T stage, and presence of LN metastases were the independent factors predicting poor prognosis. Tumor thickness as well as grade, T stage, LVI were predictors of LN metastasis. Rates of LN metastasis are <2% in LR sm1 disease, and >15% in HR sm1 disease. Pathological reporting of sm invasion should be updated for uniform analysis of endoscopic and surgical specimens. Following rigorous histopathological examination and within a close endoscopic follow-up regimen, pT1a and pT1b LRsm1 disease may be treated with curative intent endoscopically, whereas pT1b HRsm1-sm3 disease should be offered surgery.

Anaemia and its effects on tumour regression grade and survival following chemotherapy in adenocarcinoma of the oesophagus.

BACKGROUND: Anaemia reduces the efficacy of chemotherapy in gastric cancer. However, it has not been studied in oesophageal cancer. We investigated whether anaemia impacts on survival and the efficacy of chemotherapy, in adenocarcinoma of the oesophagus for those undergoing neoadjuvant chemotherapy and then surgical resection. METHODS: This prospective study included 268 patients who received neoadjuvant chemotherapy for oesophageal adenocarcinoma. Patient clinical data as well as Mandard's tumor regression grading (TRG), haemoglobin pre-chemotherapy and during the chemotherapy were compiled. The association between anaemia and TRG was tested using Chi-squared analysis, whilst survival outcomes were investigated by Kaplan-Meier and Cox regression. RESULTS: One hundred participants were anaemic before chemotherapy whilst 224 were anaemic during chemotherapy cycles. Survival analyses found a significant association between lower haemoglobin levels and decreased overall survival (P=0.048). Comparing those without anaemia against those with moderate -severe anaemia (<10.9 g/dL) found a statistically significant association in overall survival (P=0.026). Multivariate cox regression showed those with anaemia were statistically more likely to have decreased overall survival (HR 1.735, 95% CI, 1.050-2.867, P=0.032). No statistical association was seen between those with pre-chemotherapy anaemia and TRG (OR 0.675, 95% CI, 0.420-1.161, P=0.130) or those with anytime anaemia (OR 0.881, 95% CI, 0.406-1.914, P=0.931). CONCLUSIONS: These results suggest that anaemia is associated with poorer overall survival time, with lower haemoglobin levels reducing prognosis. However, there does not appear to be an association between anaemia and chemotherapy response in oesophageal adenocarcinoma.

Multicomponent analysis of the tumour microenvironment reveals low CD8 T cell number, low stromal caveolin-1 and high tenascin-C and their combination as significant prognostic markers in non-small cell lung cancer.

The complex interplay of the tumour microenvironment (TME) and its role in disease progression and response to therapy is poorly understood. The majority of studies to date focus on individual components or molecules within the TME and so lack the power correlative analysis. Here we have performed a multi-parameter analysis of the TME in 62 resectable non-small cell lung cancer (NSCLC) specimens detailing number and location of immune infiltrate, assessing markers of cancer-associated fibroblasts, caveolin-1 and tenascin-C, and correlating with clinicopathological details, as well as markers of disease progression such as epithelial-to-mesenchymal transition (EMT). The influence of individual parameters on overall survival was determined in univariate and multivariate analysis and the combination of risk factors and interplay between components analysed. Low numbers of CD8 T cells, low stromal levels of caveolin-1 or high levels of tenascin-C were significant prognostic markers of decreased overall survival in both univariate and multivariate analysis. Patients with two or more risk factors had dramatically reduced overall survival and those with all three a median survival of just 7.5 months. In addition, low levels of tumour E-cadherin correlated with reduced immune infiltrate into the tumour nests, possibly linking EMT to the avoidance of CD8 T cell control. The multicomponent approach has allowed identification of the dominant influences on overall survival, and exploration of the interplay between different components of the TME in NSCLC.

The role of adjuvant platinum-based chemotherapy in esophagogastric cancer patients who received neoadjuvant chemotherapy prior to definitive surgery.

BACKGROUND AND OBJECTIVES: For patients with operable esophagogastric cancer, peri-operative chemotherapy confers a significant overall survival benefit compared to surgery alone, however only 30-40% of patients demonstrate histopathological response. It is unclear whether those with no neoadjuvant chemotherapy response should go onto receive adjuvant chemotherapy, as no further benefit may be conferred. METHODS: Esophagogastric cancers were prospectively captured with associated histopathological tumor regression grades following neoadjuvant chemotherapy. This cohort was then interrogated for clinico-pathological and survival outcomes. RESULTS: Following neoadjuvant chemotherapy and surgery, patients with chemotherapy responsive cancers, who were administered adjuvant chemotherapy gained a significant overall survival benefit. Multivariate Cox analysis, demonstrated a final adjusted hazard ratio for adjuvant therapy of 0.509; (95%CI 0.28-0.93); P = 0.028. In contrast, patients with non-responsive tumors, who underwent adjuvant chemotherapy, did not show any survival benefit. Chemotherapy toxicity was prevalent and contributed to only half of patients receiving adjuvant chemotherapy. CONCLUSIONS: These results suggest the benefit of the adjuvant portion of chemotherapy is limited to those who demonstrate a histopathological response to neoadjuvant chemotherapy. The administration of the adjuvant portion of chemotherapy to patients without a response to neoadjuvant chemotherapy may not provide any survival benefit, while potentially causing increased morbidity.

Individual patient oesophageal cancer 3D models for tailored treatment.

BACKGROUND: A model to predict chemotherapy response would provide a marked clinical benefit, enabling tailored treatment of oesophageal cancer, where less than half of patients respond to the routinely administered chemotherapy. METHODS: Cancer cells were established from tumour biopsies taken from individual patients about to undergo neoadjuvant chemotherapy. A 3D-tumour growth assay (3D-TGA) was developed, in which cancer cells were grown with or without supporting mesenchymal cells, then subjected to chemo-sensitivity testing using the standard chemotherapy administered in clinic, and a novel emerging HDAC inhibitor, Panobinostat. RESULTS: Individual patient's cancer cells could be expanded and screened within a clinically applicable timescale of 3 weeks. Incorporating mesenchymal support within the 3D-TGA significantly enhanced both the growth and drug resistance profiles of the patient's cancer cells. The ex vivo drug response in the presence, but not absence, of mesenchymal cells accurately reflected clinical chemo-sensitivity, as measured by tumour regression grade. Combination with Panobinostat enhanced response and proved efficacious in otherwise chemo-resistant tumours. CONCLUSIONS: This novel method of establishing individual patient oesophageal cancers in the laboratory, from small endoscopic biopsies, enables clinically-relevant chemo-sensitivity testing, and reduces use of animals by providing more refined in vitro models for pre-screening of drugs. The 3D-TGA accurately predicted chemo-sensitivity in patients, and could be developed to guide tailored patient treatment. The incorporation of mesenchymal cells as the stromal cell component of the tumour micro-environment had a significant effect upon enhancing chemotherapy drug resistance in oesophageal cancer, and could prove a useful target for future drug development.

Long-term outcome of endovascular repair of popliteal artery aneurysm presents a credible alternative to open surgery.

PURPOSE: Endovascular repair of popliteal artery aneurysms (PAA) has become increasingly popular; however, long-term patency and limb salvage rates are not fully established. METHODS: A retrospective review of all endovascular PAA repairs at our institution (from 2005 to 2012) identified 34 PAAs in 26 patients, of which 32 % presented with acute symptoms. PAA were repaired with either Hemobahn(®) or Viabahn(®) endografts, using an entirely percutaneous approach. All patients were given Clopidogrel and/or aspirin postoperatively. Mean follow-up duration was 40 (range 4-86) months. Kaplan-Meier analysis was used to determine primary patency, secondary patency, and limb salvage rates. Complications and reintervention rates also were examined. RESULTS: At 1, 3, and 5 years follow-up, the primary graft patency was 88, 82, and 82 %, respectively, and secondary patency was 90, 86, and 86 %. Amputation-free survival at 1, 3, and 5 years was 97, 94, and 94 %, respectively. Technical success was achieved in 100 %. There were five graft occlusions: one was asymptomatic, one was treated with thrombolysis successfully, and one was thrombolysed but reoccluded resulting in nondisabling claudication. Two were not suitable for thrombolysis and required amputation. The overall reintervention rate was 12 %. CONCLUSIONS: The primary and secondary patency rates of endovascular repair of PAA are equivalent to the reported outcome of open repair. Reintervention and limb salvage rate appears better than open repair. With improved long-term outcomes, endovascular repair can be considered a credible treatment strategy for routine uncomplicated PAA.

The views of doctors in their first year of medical practice on the lasting impact of a preparation for house officer course they undertook as final year medical students.

BACKGROUND: The UK General Medical Council recommends that medical students have the opportunity of shadowing the outgoing new doctor whose post they will soon undertake. At the University of Nottingham the two-week shadowing period was preceded by two weeks of lectures/seminars wherein students followed sessions on topics such as common medical/surgical emergencies, contracts, time management, surviving the first two years of clinical practice, careers advice and so on. The present study aimed to gain a better knowledge and understanding of the lasting impact of a four-week preparation course for new Foundation Year 1 doctors [F1 s - interns]. The objectives chosen to achieve this aim were: 1/ to determine the extent to which the lecture/seminar course and shadowing period achieved their stated aim of smoothing the transition from life as a medical student to work as a new doctor; 2/ to evaluate perceptions of the importance of various forms of knowledge in easing the transition between medical student and new doctor METHOD: In the spring of 2007, 90 graduates from Nottingham were randomly selected and then emailed a link to a short, online survey of quantitative and qualitative questions. Of these 76 responded. Analysis of quantitative data was carried out using SPSS 16.0 and employed McNemar's test. Analysis of the qualitative data was carried out using the constant comparative method. RESULTS: Only 31% of respondents strongly agreed or agreed that the lecture/seminar part of the course prepared them well for their first FY1 post; 14% agreed that during their first job they drew on the knowledge gained during the lecture/seminar course; 94% strongly agreed or agreed that the shadowing part of the course was more useful than the lecture/seminar part. Experiential knowledge gained in the shadowing was the most highly valued, followed by procedural knowledge with propositional knowledge coming far behind. CONCLUSIONS: Our study shows that new doctors retrospectively value most the knowledge they are able to transfer to the workplace and value least material which seems to repeat what they had learned for their final exams.