599 research outputs found
Interfacing polymeric scaffolds with primary pancreatic ductal adenocarcinoma cells to develop 3D cancer models
We analyzed the interactions between human primary cells from pancreatic ductal adenocarcinoma (PDAC) and polymeric scaffolds to develop 3D cancer models useful for mimicking the biology of this tumor. Three scaffold types based on two biocompatible polymeric formulations, such as poly(vinyl alcohol)/gelatin (PVA/G) mixture and poly(ethylene oxide terephthalate)/poly(butylene terephthalate) (PEOT/PBT) copolymer, were obtained via different techniques, namely, emulsion and freeze-drying, compression molding followed by salt leaching, and electrospinning. In this way, primary PDAC cells interfaced with different pore topographies, such as sponge-like pores of different shape and size or nanofiber interspaces. The aim of this study was to investigate the influence played by the scaffold architecture over cancerous cell growth and function. In all scaffolds, primary PDAC cells showed good viability and synthesized tumor-specific metalloproteinases (MMPs) such as MMP-2, and MMP-9. However, only sponge-like pores, obtained via emulsion-based and salt leaching-based techniques allowed for an organized cellular aggregation very similar to the native PDAC morphological structure. Differently, these cell clusters were not observed on PEOT/PBT electrospun scaffolds. MMP-2 and MMP-9, as active enzymes, resulted to be increased in PVA/G and PEOT/PBT sponges, respectively. These findings suggested that spongy scaffolds supported the generation of pancreatic tumor models with enhanced aggressiveness. In conclusion, primary PDAC cells showed diverse behaviors while interacting with different scaffold types that can be potentially exploited to create stage-specific pancreatic cancer models likely to provide new knowledge on the modulation and drug susceptibility of MMPs
Two benthic diatoms, nanofrustulum shiloi and striatella unipunctata, encapsulated in alginate beads, influence the reproductive efficiency of paracentrotus lividus by modulating the gene expression
Physiological effects of algal metabolites is a key step for the isolation of interesting bioactive compounds. Invertebrate grazers may be fed on live diatoms or dried, pelletized, and added to compound feeds. Any method may reveal some shortcomings, due to the leaking of wound-activated compounds in the water prior to ingestion. For this reason, encapsulation may represent an important step of bioassay-guided fractionation, because it may assure timely preservation of the active compounds. Here we test the effects of the inclusion in alginate (biocompatible and non-toxic delivery system) matrices to produce beads containing two benthic diatoms for sea urchin Paracentrotus lividus feeding. In particular, we compared the effects of a diatom whose influence on P. lividus was known (Nanofrustulum shiloi) and those of a diatom suspected to be harmful to marine invertebrates, because it is often present in blooms (Striatella unipunctata). Dried N. shiloi and S. unipunctata were offered for one month after encapsulation in alginate hydrogel beads and the larvae produced by sea urchins were checked for viability and malformations. The results indicated that N. shiloi, already known for its toxigenic effects on sea urchin larvae, fully conserved its activity after inclusion in alginate beads. On the whole, benthic diatoms affected the embryogenesis of P. lividus, altering the expression of several genes involved in stress response, development, skeletogenesis and detoxification processes. Interactomic analysis suggested that both diatoms activated a similar stress response pathway, through the up-regulation of hsp60, hsp70, NF-κB, 14-3-3 ε and MDR1 genes. This research also demonstrates that the inclusion in alginate beads may represent a feasible technique to isolate diatom-derived bioactive compounds
Prospective qualitative and quantitative non-invasive evaluation of intestinal acute GVHD by contrast-enhanced ultrasound sonography.
Intestinal acute GVHD (I-aGVHD) is a life-threatening complication after allografting. Non-invasive bed-side procedures to evaluate extension and treatment response are still lacking. We hypothesized that, during I-aGVHD, contrast-enhanced ultrasound sonography (CEUS) could detect microcirculation changes (MVC) of the bowel wall (BW) and help to monitor treatment response. We prospectively employed CEUS in 83 consecutive patients. Of these, 14 patients with biopsy-proven intestinal GVHD (I-GVHD) were defined as the study group, whereas 16 patients with biopsy-proven stomach GVHD (U-GVHD) without intestinal symptoms, 6 normal volunteers and 4 patients with neutropenic enterocolitis were defined as the control group. All patients were evaluated with both standard ultrasonography (US) and CEUS at the onset of intestinal symptoms, during clinical follow-up and at flare of symptoms. Standard US revealed BW thickening of multiple intestinal segments, useful to determine the extension of GVHD. CEUS showed MVC, which correlated with GVHD activity, treatment response, and predicted flare of intestinal symptoms. US and CEUS findings were superimposable at diagnosis and in remission. CEUS was, however, more sensitive and specific to identify subclinical activity in patients with clinical relevant improvement. These findings were not observed in the control groups. CEUS is a non-invasive, easily reproducible bed-side tool useful to monitor I-aGVHD
Efficacy and safety of combination therapy with everolimus and sorafenib for recurrence of hepatocellular carcinoma after liver transplantation.
Background Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is still associated with a dismal outcome. Combination therapy with everolimus (EVL) and vascular endothelial growth factor inhibitor sorafenib (SORA) is based on the role of both b-Raf and mammalian target of rapamycin/protein kinase B pathways in the pathogenesis of HCC and is being investigated in clinical practice. Methods This was a single-center retrospective analysis on LT recipients with unresectable HCC recurrence and undergoing combination therapy with EVL and SORA. Patients were included if they were switched to EVL+SORA at any time after surgery. Primary endpoint was overall survival (OS) after both LT and recurrence, and response to treatment based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) in the intention-to-treat (ITT) population. Secondary analysis was safety of combination therapy with EVL and SORA in the population of patients who received ≥1 dose of the study drug. Results Seven patients (100% male; median age 53 years [interquartile range (IQR) 9 years]) were considered for analysis. HCC recurrence was diagnosed at a median (IQR) interval since LT of 9 (126) months, and patients were administered EVL+SORA at a median interval since LT of 11 (126) months. Baseline immunosuppression was with tacrolimus (TAC) in 2 patients (28.6%), cyclosporine (CsA) in 2 (28.6%), and EVL monotherapy in 3 (42.8%). At a median (IQR) follow-up of 6.5 (14) months, 5 patients (71.4%) were alive, 4 of them (57.1%) with tumor progression according to the mRECIST criteria. Median (IQR) time to progression was 3.5 (12) months. Two patients died at a median (IQR) follow-up of 5 (1) months owing to tumor progression in 1 patient (14.3%) and sepsis in the other (14.3%). EVL monotherapy was achieved in 6 patients (85.7%), whereas 1patient (14.3%) could not withdraw from calcineurin inhibitor owing to acute rejection. Treatment complications were: hand-foot syndrome in 5 patients (71.4%), hypertension in 1 (14.3%), alopecia in 1 (14.3%), hypothyroidism in 1 (14.3%), diarrhea in 2 (28.6%), pruritus in 1 (14.3%), abdominal pain in 1 (14.3%), rash in 1 (14.3%), asthenia in 3 (42.8%), anorexia in 3 (42.8%), and hoarseness in 2 (28.6%). Adverse events led to temporary SORA discontinuation in 2 patients (28.6%) and to SORA dose reduction in 3 (42.8%). Conclusions Treatment of HCC recurrence after LT with a combination regimen of EVL+ SORA is challenging because of SORA-related complications. Longer follow-up periods and larger series are needed to better capture the impact of such combination treatment on tumor progression and patient survival.BACKGROUND:
Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is still associated with a dismal outcome. Combination therapy with everolimus (EVL) and vascular endothelial growth factor inhibitor sorafenib (SORA) is based on the role of both b-Raf and mammalian target of rapamycin/protein kinase B pathways in the pathogenesis of HCC and is being investigated in clinical practice.
METHODS:
This was a single-center retrospective analysis on LT recipients with unresectable HCC recurrence and undergoing combination therapy with EVL and SORA. Patients were included if they were switched to EVL+SORA at any time after surgery. Primary endpoint was overall survival (OS) after both LT and recurrence, and response to treatment based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) in the intention-to-treat (ITT) population. Secondary analysis was safety of combination therapy with EVL and SORA in the population of patients who received ≥1 dose of the study drug.
RESULTS:
Seven patients (100% male; median age 53 years [interquartile range (IQR) 9 years]) were considered for analysis. HCC recurrence was diagnosed at a median (IQR) interval since LT of 9 (126) months, and patients were administered EVL+SORA at a median interval since LT of 11 (126) months. Baseline immunosuppression was with tacrolimus (TAC) in 2 patients (28.6%), cyclosporine (CsA) in 2 (28.6%), and EVL monotherapy in 3 (42.8%). At a median (IQR) follow-up of 6.5 (14) months, 5 patients (71.4%) were alive, 4 of them (57.1%) with tumor progression according to the mRECIST criteria. Median (IQR) time to progression was 3.5 (12) months. Two patients died at a median (IQR) follow-up of 5 (1) months owing to tumor progression in 1 patient (14.3%) and sepsis in the other (14.3%). EVL monotherapy was achieved in 6 patients (85.7%), whereas 1patient (14.3%) could not withdraw from calcineurin inhibitor owing to acute rejection. Treatment complications were: hand-foot syndrome in 5 patients (71.4%), hypertension in 1 (14.3%), alopecia in 1 (14.3%), hypothyroidism in 1 (14.3%), diarrhea in 2 (28.6%), pruritus in 1 (14.3%), abdominal pain in 1 (14.3%), rash in 1 (14.3%), asthenia in 3 (42.8%), anorexia in 3 (42.8%), and hoarseness in 2 (28.6%). Adverse events led to temporary SORA discontinuation in 2 patients (28.6%) and to SORA dose reduction in 3 (42.8%).
CONCLUSIONS:
Treatment of HCC recurrence after LT with a combination regimen of EVL+ SORA is challenging because of SORA-related complications. Longer follow-up periods and larger series are needed to better capture the impact of such combination treatment on tumor progression and patient survival
Dysregulation of NF–Y splicing drives metabolic rewiring and aggressiveness in colon cancer
NF-Y is an evolutionarily conserved transcription factor that binds specifically to the CCAAT
elements of eukaryotic genes, most of which frequently deregulated in cancer. NF-YA, the
regulatory subunit of the NF-Y complex, has two isoforms generated by alternative splicing,
NF-YAl and NF-YAs, which differ in the transactivation domain.
Transcriptomic data from The Cancer Genome Atlas (TCGA) database highlighted a
significant increase in the expression of NF-YAs at the expense of NF-YAl in colorectal cancer
(CRC), compared to healthy tissues. Despite this, high NF-YAl levels predict lower patients’
survival and distinguish the mesenchymal molecular subtype CMS4, which is characterized by
the worst prognosis.
Through the analysis of 3D cellular models, we demonstrated that altered expression of genes
related to extracellular matrix and epithelial-mesenchymal transition sustains enhanced
migratory and invasive behavior of NF-YAl-transduced cells. Moreover, the integration of
metabolomics, bioenergetics and transcriptional analyses demonstrated a direct role for NFYAl
in metabolic flexibility of cancer cells that adjust their metabolism in response to
environmental changes to potentiate migration. The zebrafish xenograft model confirmed the
metastatic potential triggered by NF-YAl in CRC cells.
Altogether, our data highlight the transcriptional role of NF-YAl in CRC aggressiveness and
suggest splice-switching strategies to hinder NF-YAl-induced metastatic dissemination
Magnetic Field Stimulated Transitions of Excited States in Fast Muonic Helium Ions
It is shown that one can stimulate, by using the present-day laboratory
magnetic fields, transitions between the sub-levels of fast
ions formating in muon catalyzed fusion. Strong fields also cause the
self-ionization from highly excited states of such muonic ions. Both effects
are the consequence of the interaction of the bound muon with the oscillating
field of the Stark term coupling the center-of-mass and muon motions of the
ion due to the non-separability of the collective and internal
variables in this system. The performed calculations show a possibility to
drive the population of the sub-levels by applying a field of a few
, which affects the reactivation rate and is especially important to the
-ray production in muon catalyzed fusion. It is also shown that
the splitting in due to the vacuum polarization slightly
decreases the stimulated transition rates.Comment: 5 figure
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