Engineering secretory amyloids for remote and highly selective destruction of metastatic foci

Altres ajuts: to EU COST Action CA 17140Functional amyloids produced in bacteria as nanoscale inclusion bodies are intriguing but poorly explored protein materials with wide therapeutic potential. Since they release functional polypeptides under physiological conditions, these materials can be potentially tailored as mimetic of secretory granules for slow systemic delivery of smart protein drugs. To explore this possibility, bacterial inclusion bodies formed by a self-assembled, tumor-targeted Pseudomonas exotoxin (PE24) are administered subcutaneously in mouse models of human metastatic colorectal cancer, for sustained secretion of tumor-targeted therapeutic nanoparticles. These proteins are functionalized with a peptidic ligand of CXCR4, a chemokine receptor overexpressed in metastatic cancer stem cells that confers high selective cytotoxicity in vitro and in vivo. In the mouse models of human colorectal cancer, time-deferred anticancer activity is detected after the subcutaneous deposition of 500 µg of PE24-based amyloids, which promotes a dramatic arrest of tumor growth in the absence of side toxicity. In addition, long-term prevention of lymphatic, hematogenous, and peritoneal metastases is achieved. These results reveal the biomedical potential and versatility of bacterial inclusion bodies as novel tunable secretory materials usable in delivery, and they also instruct how therapeutic proteins, even with high functional and structural complexity, can be packaged in this convenient format

SerpinB2 regulates stromal remodelling and local invasion in pancreatic cancer

Pancreatic cancer has a devastating prognosis, with an overall 5-year survival rate of ~8%, restricted treatment options and characteristic molecular heterogeneity. SerpinB2 expression, particularly in the stromal compartment, is associated with reduced metastasis and prolonged survival in pancreatic ductal adenocarcinoma (PDAC) and our genomic analysis revealed that SERPINB2 is frequently deleted in PDAC. We show that SerpinB2 is required by stromal cells for normal collagen remodelling in vitro, regulating fibroblast interaction and engagement with collagen in the contracting matrix. In a pancreatic cancer allograft model, co-injection of PDAC cancer cells and SerpinB2(-/-) mouse embryonic fibroblasts (MEFs) resulted in increased tumour growth, aberrant remodelling of the extracellular matrix (ECM) and increased local invasion from the primary tumour. These tumours also displayed elevated proteolytic activity of the primary biochemical target of SerpinB2-urokinase plasminogen activator (uPA). In a large cohort of patients with resected PDAC, we show that increasing uPA mRNA expression was significantly associated with poorer survival following pancreatectomy. This study establishes a novel role for SerpinB2 in the stromal compartment in PDAC invasion through regulation of stromal remodelling and highlights the SerpinB2/uPA axis for further investigation as a potential therapeutic target in pancreatic cancer

Tetrahydrouridine Inhibits Cell Proliferation through Cell Cycle Regulation Regardless of Cytidine Deaminase Expression Levels

Tetrahydrouridine (THU) is a well characterized and potent inhibitor of cytidine deaminase (CDA). Highly expressed CDA catalyzes and inactivates cytidine analogues, ultimately contributing to increased gemcitabine resistance. Therefore, a combination therapy of THU and gemcitabine is considered to be a potential and promising treatment for tumors with highly expressed CDA. In this study, we found that THU has an alternative mechanism for inhibiting cell growth which is independent of CDA expression. Three different carcinoma cell lines (MIAPaCa-2, H441, and H1299) exhibited decreased cell proliferation after sole administration of THU, while being unaffected by knocking down CDA. To investigate the mechanism of THU-induced cell growth inhibition, cell cycle analysis using flow cytometry was performed. This analysis revealed that THU caused an increased rate of G1-phase occurrence while S-phase occurrence was diminished. Similarly, Ki-67 staining further supported that THU reduces cell proliferation. We also found that THU regulates cell cycle progression at the G1/S checkpoint by suppressing E2F1. As a result, a combination regimen of THU and gemcitabine might be a more effective therapy than previously believed for pancreatic carcinoma since THU works as a CDA inhibitor, as well as an inhibitor of cell growth in some types of pancreatic carcinoma cells

Advanced pancreatic adenocarcinoma outcomes with transition from devolved to centralised care in a regional Cancer Centre

Background: Previous observations suggest suboptimal ‘real world’ survival outcomes for advanced pancreatic adenocarcinoma. We hypothesized that centralisation of advanced pancreatic adenocarcinoma management would improve chemotherapy treatment and survival from the disease. Methods: The data was prospectively collected on all cases of advanced pancreatic adenocarcinoma reviewed through Clatterbridge Cancer Centre according to two groups; 1 October 2009–31st Dec 2010 (devolved care) or 1 January 2013–31 March 2014 (centralised care). Analysis included treatment received, 30-day chemotherapy mortality rate and overall survival (OS). Results: More patients received chemotherapy with central care (67.0% (n=115) vs 43.0% (n=121); P=2.2 × 10−4) with no difference in 30-day mortality (20.8% vs 25%; P=0.573) but reduced time to commencement of chemotherapy (18 vs 28 days, P=1.0 × 10−3). More patients received second-line chemotherapy with central care (23.4% vs 1.9%, P=1.4 × 10−4), while OS was significantly increased with central care (median: Five vs three months, HR 0.785, P=0.045). Exploratory analysis suggested that it was those with a poorer performance status, elderly or with metastatic disease who benefited the most from transition to central care. Conclusions: A centralised clinic model for advanced pancreatic cancer management resulted in prompt, safe and higher use of chemotherapy compared with devolved care. This was associated with a modest survival benefit. Prospective studies are required to validate the findings reported and the basis for improved survival with centralised care

Body Composition, Symptoms, and Survival in Advanced Cancer Patients Referred to a Phase I Service

Background: Body weight and body composition are relevant to the outcomes of cancer and antineoplastic therapy. However, their role in Phase I clinical trial patients is unknown. Methods: We reviewed symptom burden, body composition, and survival in 104 patients with advanced cancer referred to a Phase I oncology service. Symptom burden was analyzed using the MD Anderson Symptom Assessment Inventory(MDASI); body composition was evaluated utilizing computerized tomography(CT) images. A body mass index (BMI)$25 kg/m 2 was considered overweight. Sarcopenia, severe muscle depletion, was assessed using CT-based criteria. Results: Most patients were overweight (n = 65, 63$25 kg/m 2. Sarcopenic patients were older and less frequently African-American. Symptom burden did not differ among patients classified according to BMI and presence of sarcopenia. Median (95% confidence interval) survival (days) varied according to body composition: 215 (71–358) (BMI,25 kg/m 2; sarcopenic), 271 (99–443) (BMI,25 kg/m 2; non-sarcopenic), 484 (286–681) (BMI$25 kg/m 2; sarcopenic); 501 d (309–693) (BMI$25 kg/m 2; non-sarcopenic). Higher muscle index and gastrointestinal cancer diagnosis predicted longer survival in multivariate analysis after controlling for age, gender, performance status, and fat index. Conclusions: Patients referred to a Phase I clinic had a high frequency of sarcopenia and a BMI$25 kg/m 2, independent o