Follow-up after curative resection for gastric cancer. Is it time to tailor it?

There is still no consensus on the follow-up frequency and regimen after curative resection for gastric cancer. Moreover, controversy exists regarding the utility of follow-up in improving survival, and the recommendations of experts and societies vary considerably. The main reason to establish surveillance programs is to diagnose tumor recurrence or metachronous cancers early and to thereby provide prompt treatment and prolong survival. In the setting of gastric malignancies, other reasons have been put forth: (1) the detection of adverse effects of a previous surgery, such as malnutrition or digestive sequelae; (2) the collection of data; and (3) the identification of psychological and/or social problems and provision of appropriate support to the patients. No randomized controlled trials on the role of follow-up after curative resection of gastric carcinoma have been published. Herein, the primary retrospective series and systematic reviews on this subject are analyzed and discussed. Furthermore, the guidelines from international and national scientific societies are discussed. Follow-up is recommended by the majority of institutions; however, there is no real evidence that follow-up can improve long-term survival rates. Several studies have demonstrated that it is possible to stratify patients submitted to curative gastrectomy into different classes according to the risk of recurrence. Furthermore, promising studies have identified several molecular markers that are related to the risk of relapse and to prognosis. Based on these premises, a promising strategy will be to tailor follow-up in relation to the patient and tumor characteristics, molecular marker status, and individual risk of recurrence

High-throughput Human Cell Reprogramming through Substrate and Microfluidics Integration

Human cells and tissues are key systems to study human biology and physiology, and to develop new strategies and targeting drugs for human diseases. Since the study and testing on human beings may not be acceptable due to exposure to risks and practical and ethical concerns, in vitro strategies are of paramount importance to rely on human organism and avoid non-fully predictive animal models. The demand of research in clinical and industrial fields for effective, representative and affordable strategies is undoubtedly increasing. Conventional cell culture systems and drug discovery are normally performed in vessels with a characteristic dimension in the order of centimeters. Nutrients are delivered to cells through liquid media containing balanced saline buffers and oligo-elements. A reasonable amount of medium is necessary to homogeneously cover a cell layer and must exchanged with fresh media to maintain a proper amount of available nutrients and remove released waste products. Many studies and applications require expensive reagents and are subjected to limited data throughput. The discovery of reprogramming process by 2012 Nobel Prize Yamanaka opened breakthrough new perspective on research and clinical applications. Basically, from a patient’s skin biopsy it is now possible to derive induced pluripotent stem cells (iPSC) and to obtain new tissues for an ad hoc self-repair. So far, human iPSC (hiPSC) have not been applied to clinics due to some unexplored aspects on their derivation, non clinical-grade methods and the significative cost of hiPSC derivation per patient. The down-scale of reprogramming process could provide an unique opportunity to derive cost-effective hiPSC and obtain valuable human in vitro tissues. The aim of this thesis is the development of a comprehensive platform for the reprogramming of human cells at the microscale. To this end, we focused on the development of cell microenvironment which is composed by both soluble and solid components. During this thesis, synthetic and biodegradable hydrogels were developed. The large-scale production of mechanically-tunable poly-acrylamide-based substrates were fundamental to reveal the interaction occurring between substrate stiffness and cell behavior and fate. Engineering of biodegradable hydrogels has revealed the potential to develop in vitro functional tissues and to integrate them at a later stage in patients. Chemical modifications were transferred to topological substrate control and in turn in microfluidic platforms. Microfluidic chip environment and management was designed in order to allow long-term adhesion, culture and biologically relevant cell behaviors. Adhesion proteins fundamental for cell attachment and growth were modified and integrated with the micronized substrates. Since medium for microfluidic cell culture relies on perfusion, continuous or periodic flow could be applied. Thus, we studied the management of media delivery in order to determine the best strategy for long-term cell cultures. The achievements obtained with both substrate and microfluidic cell culture development was applied to the generation of a new platform for hiPSC derivation, differentiation and testing at the microscale. For the first time, it is possible to obtain human iPSC clones in microfluidics with a remarked reduction of minimum requirements (materials, reagents, overall expenses). The production of cost effective hiPSC can lead to a mass production of characterized and functional tissues that can be either integrated in 3D developed constructs and serve as valuable tissue source derivation for drug development. Our platform opens new perspectives in studying and treating both abundant and rare diseases involving both scientists and entrepreneur

Influence of perineural invasion in predicting overall survival and disease-free survival in patients With locally advanced gastric cancer

Background The aim of the present study was to evaluate the prognostic significance of perineural invasion (PNI) in locally advanced gastric cancer patients who underwent D2 gastrectomy and adjuvant chemotherapy. Methods The records of a series of 103 patients undergoing D2 gastrectomy with curative intent combined with adjuvant chemotherapy from January 2004 to December 2014 were retrospectively reviewed. Results PNI was positive in 47 (45.6%) specimens. The 1-, 3-, and 5-year overall survival rates were 81%, 55%, and 42%, respectively. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 76%, 57%, and 49%, respectively. A multivariate analysis showed that age number of positive lymph nodes, T stage, and PNI were independently associated with overall survival. Regarding DFS, the multivariate analysis showed that only PNI was independently associated with DFS. Conclusions PNI and T stage and positive lymph nodes are independent markers of poor prognosis in patients with gastric cancer. PNI should be incorporated in the postoperative staging system for planning follow-up after surgery and in our opinion to propose more aggressive postoperative therapies in PNI-positive patients

The role of autophagy in liver epithelial cells and its Impact on systemic homeostasis

Autophagy plays a role in several physiological and pathological processes as it controls the turnover rate of cellular components and influences cellular homeostasis. The liver plays a central role in controlling organisms’ metabolism, regulating glucose storage, plasma proteins and bile synthesis and the removal of toxic substances. Liver functions are particularly sensitive to autophagy modulation. In this review we summarize studies investigating how autophagy influences the hepatic metabolism, focusing on fat accumulation and lipids turnover. We also describe how autophagy affects bile production and the scavenger function within the complex homeostasis of the liver. We underline the role of hepatic autophagy in counteracting the metabolic syndrome and the associated cardiovascular risk. Finally, we highlight recent reports demonstrating how the autophagy occurring within the liver may affect skeletal muscle homeostasis as well as different extrahepatic solid tumors, such as melanoma

The staging of gastritis with the olga system in the italian setting. histological features and gastric cancer risk

BACKGROUND: Recently OLGA (Operative Link on Gastritis Assessment) classification has been proposed to identify high-risk forms of gastritis that can evolve in gastric cancer (stages III and IV). Helicobacter pylori infection and age older than 40 have been considered as independent risk factor for high-risk OLGA stages

Complication of Gastric Cancer Surgery: A Single Centre Experience

Background/aim: Gastric cancer surgery is still characterised by high morbidity and mortality. However, in 2018 an online platform, GASTRODATA has been proposed in Europe to standardize the recording of gastric surgery complications. The aim of the study was to present a single center experience regarding incidence and grading of acute postoperative complications in a population of patients treated surgically for gastric cancer on the basis of the gastrodata online platform. Patients and methods: The present study was a single center, observational, retrospective trial held in the General Surgery Unit of the Sant'Andrea Hospital of Rome. The study included 181 consecutive patients who underwent gastric surgical resection for cancer from May 2004 to December 2020 with curative R0 purpose. Results: Thirty-three percent of patients reported at least one complication, while seventeen percent of the whole population reported a complication classified as at least grade 3 on the Clavien Dindo Classification. The most frequent complications were disorders of the respiratory system (13.3%), followed by bleeding (7.6%) and wound infections (6.2%). Deaths accounted for 3.7% of the population. Conclusion: A list of defined complications of gastrectomy, if systematically adopted in the Literature, could lead to a reduction in the wide variation of proposals for treatment and assessment. Objectively evaluating the impact of complications on outcomes can lead to quality improvement project proposals

The FXR agonist obeticholic acid inhibits the cancerogenic potential of human cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive cancer with high resistance to chemotherapeutics. CCA is enriched in cancer stem cells, which correlate with aggressiveness and prognosis. FXR, a member of the metabolic nuclear receptor family, is markedly down-regulated in human CCA. Our aim was to evaluate, in primary cultures of human intrahepatic CCA (iCCA), the effects of the FXR agonist obeticholic acid (OCA), a semisynthetic bile acid derivative, on their cancerogenic potential. Primary human iCCA cell cultures were prepared from surgical specimens of mucinous or mixed iCCA subtypes. Increasing concentrations (0–2.5 μM) of OCA were added to culture media and, after 3–10 days, effects on proliferation (MTS assay, cell population doubling time), apoptosis (annexin V-FITC/propidium iodide), cell migration and invasion (wound healing response and Matrigel invasion assay), and cancerogenic potential (spheroid formation, clonogenic assay, colony formation capacity) were evaluated. Results: FXR gene expression was downregulated (RT-qPCR) in iCCA cells vs normal human biliary tree stem cells (p < 0.05) and in mucinous iCCA vs mixed iCCA cells (p < 0.05) but was upregulated by addition of OCA. OCA significantly (p < 0.05) inhibited proliferation of both mucinous and mixed iCCA cells, starting at a concentration as low as 0.05 μM. Also, CDCA (but not UDCA) inhibited cell proliferation, although to a much lower extent than OCA, consistent with its different affinity for FXR. OCA significantly induced apoptosis of both iCCA subtypes and decreased their in vitro cancerogenic potential, as evaluated by impairment of colony and spheroid formation capacity and delayed wound healing and Matrigel invasion. In general, these effects were more evident in mixed than mucinous iCCA cells. When tested together with Gemcitabine and Cisplatin, OCA potentiated the anti-proliferative and pro-apoptotic effects of these chemotherapeutics, but mainly in mixed iCCA cells. OCA abolished the capacity of both mucinous and mixed iCCA cells to form colonies when administered together with Gemcitabine and Cisplatin. In subcutaneous xenografts of mixed iCCA cells, OCA alone or combined with Gemcitabine or Cisplatin markedly reduced the tumor size after 5 weeks of treatment by inducing necrosis of tumor mass and inhibiting cell proliferation. In conclusion, FXR is down-regulated in iCCA cells, and its activation by OCA results in anti-cancerogenic effects against mucinous and mixed iCCA cells, both in vitro and in vivo. The effects of OCA predominated in mixed iCCA cells, consistent with the lower aggressiveness and the higher FXR expression in this CCA subtype. These results, showing the FXR-mediated capacity of OCA to inhibit cholangiocarcinogenesis, represent the basis for testing OCA in clinical trials of CCA patients

Polysaccharide hydrogels for multiscale 3D printing of pullulan scaffolds

Structurally and mechanically similar to the extracellular matrix (ECM), biomimetic hydrogels offer a number of opportunities in medical applications. However, the generation of synthetic microenvironments that simulate the effects of natural tissue niches on cell growth and differentiation requires new methods to control hydrogel feature resolution, biofunctionalization and mechanical properties. Here we show how these goals can be achieved by using a pullulan-based hydrogel, engineered in composition and server as cell-adhesive hydrogel, 3D photo-printable in dimension, ranging from the macro- to the micro-scale dimensions, and of tunable mechanical properties. For this, we used absorbers that limit light penetration, achieving 3D patterning through stereolithography with feature vertical resolution of 200 μm and with overall dimension up to several millimeters. Furthermore, we report the fabrication of 3D pullulan-modified hydrogels by two-photon lithography, with sub-millimetric dimensions and minimum feature sizes down to some microns. These materials open the possibility to produce multiscale printed scaffolds that here we demonstrate to be inert for cell adhesion, but biologically compatible and easily functionalizable with cell adhesive proteins. Under these conditions, successful cell cultures were established in 2D and 3D. Keywords: Hydrogel, Biomaterials, Polysaccharide, Pullulan, 3D printing, Two photon laser lithography, Mesenchymal stromal cell

c-FLIP regulates autophagy by interacting with Beclin-1 and influencing its stability

c-FLIP (cellular FLICE-like inhibitory protein) protein is mostly known as an apoptosis modulator. However, increasing data underline that c-FLIP plays multiple roles in cellular homoeostasis, influencing differently the same pathways depending on its expression level and isoform predominance. Few and controversial data are available regarding c-FLIP function in autophagy. Here we show that autophagic flux is less effective in c-FLIP−/− than in WT MEFs (mouse embryonic fibroblasts). Indeed, we show that the absence of c-FLIP compromises the expression levels of pivotal factors in the generation of autophagosomes. In line with the role of c-FLIP as a scaffold protein, we found that c-FLIPL interacts with Beclin-1 (BECN1: coiled-coil, moesin-like BCL2-interacting protein), which is required for autophagosome nucleation. By a combination of bioinformatics tools and biochemistry assays, we demonstrate that c-FLIPL interaction with Beclin-1 is important to prevent Beclin-1 ubiquitination and degradation through the proteasomal pathway. Taken together, our data describe a novel molecular mechanism through which c-FLIPL positively regulates autophagy, by enhancing Beclin-1 protein stability