81 research outputs found
Improving Dermal Delivery of Rose Bengal by Deformable Lipid Nanovesicles for Topical Treatment of Melanoma
Cutaneous melanoma is one of the most aggressive and metastatic forms of skin cancer. However, current therapeutic options present several limitations, and the annual death rate due to melanoma increases every year. Dermal delivery of nanomedicines can effectively eradicate primary melanoma lesions, avoid the metastatic process, and improve survival. Rose Bengal (RB) is a sono-photosensitizer drug with intrinsic cytotoxicity toward melanoma without external stimuli but the biopharmaceutical profile limits its clinical use. Here, we propose deformable lipid nanovesicles, also known as transfersomes (TF), for the targeted dermal delivery of RB to melanoma lesions to eradicate them in the absence of external stimuli. Considering RB's poor ability to cross the stratum corneum and its photosensitizer nature, transfersomal carriers were selected simultaneously to enhance RB penetration to the deepest skin layers and protect RB from undesired photodegradation. RB-loaded TF dispersion (RB-TF), prepared by a modified reverse-phase evaporation method, were nanosized with a ζ-potential value below -30 mV. The spectrophotometric and fluorimetric analysis revealed that RB efficiently interacted with the lipid phase. The morphological investigations (transmission electron microscopy and small-angle X-ray scattering) proved that RB intercalated within the phospholipid bilayer of TF originating unilamellar and deformable vesicles, in contrast to the rigid multilamellar unloaded ones. Such outcomes agree with the results of the in vitro permeation study, where the lack of a burst RB permeation peak for RB-TF, observed instead for the free drug, suggests that a significant amount of RB interacted with lipid nanovesicles. Also, RB-TF proved to protect RB from undesired photodegradation over 24 h of direct light exposure. The ex vivo epidermis permeation study proved that RB-TF significantly increased RB's amount permeating the epidermis compared to the free drug (78.31 vs 38.31%). Finally, the antiproliferative assays on melanoma cells suggested that RB-TF effectively reduced cell growth compared to free RB at the concentrations tested (25 and 50 μM). RB-TF could potentially increase selectivity toward cancer cells. Considering the outcomes of the characterization and cytotoxicity studies performed on RB-TF, we conclude that RB-TF represents a valid potential alternative tool to fight against primary melanoma lesions via dermal delivery in the absence of light
Inhomogeneous Diastereomeric Composition of Mongersen Antisense Phosphorothioate Oligonucleotide Preparations and Related Pharmacological Activity Impairment
Mongersen is a 21-mer antisense oligonucleotide designed to downregulate Mothers against decapentaplegic homolog 7 (SMAD7) expression to treat Crohn's disease. Mongersen was manufactured in numerous batches at different scales during several years of clinical development, which all appeared identical, using common physicochemical analytical techniques, while only phosphorous-31 nuclear magnetic resonance (P-31-NMR) in solution showed marked differences. Close-up analysis of 27 mongersen batches revealed marked differences in SMAD7 downregulation in a cell-based assay. Principal component analysis of P-31-NMR profiles showed strong correlation with SMAD7 downregulation and, therefore, with pharmacological efficacy in vitro. Mongersen contains 20 phosphorothioate (PS) linkages, whose chirality (Rp/Sp) was not controlled during manufacturing. A different diastereomeric composition throughout batches would lead to superimposable analytical data, but to distinct P-31-NMR profiles, as indeed we found. We tentatively suggest that this may be the origin of different biological activity. As similar manifolds are expected for other PS-based oligonucleotides, the protocol described here provides a general method to identify PS chirality issues and a chemometric tool to score each preparation for this elusive feature
A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors
A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 × 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma
Characterisation and radioimmunotherapy of L19-SIP, an anti-angiogenic antibody against the extra domain B of fibronectin, in colorectal tumour models
Angiogenesis is a characteristic feature of tumours and other disorders. The human monoclonal antibody L19- SIP targets the extra domain B of fibronectin, a marker of angiogenesis expressed in a range of tumours. The aim of this study was to investigate whole body distribution, tumour localisation and the potential of radioimmunotherapy with the L19-small immunoprotein (SIP) in colorectal tumours. Two colorectal tumour models with highly different morphologies, the SW1222 and LS174T xenografts, were used in this study. Localisation and retention of the L19-SIP antibody at tumour vessels was demonstrated using immunohistochemistry and Cy3-labelled L19-SIP. Whole body biodistribution studies in both tumour models were carried out with 125I-labelled L19-SIP. Finally, 131I-labelled antibody was used to investigate the potential of radioimmunotherapy in SW1222 tumours. Using immunohistochemistry, we confirmed extra domain B expression in the tumour vasculature. Immunofluorescence demonstrated localisation and retention of injected Cy3-labelled L19-SIP at the abluminal side of tumour vessels. Biodistribution studies using a 125I-labelled antibody showed selective tumour uptake in both models. Higher recorded values for localisation were found in the SW1222 tumours than in the LS174T (7.9 vs 6.6 %ID g−1), with comparable blood clearance for both models. Based on these results, a radioimmunotherapy study was performed in the SW1222 xenograft using 131I-Labelled L19-SIP (55.5 MBq), which showed selective tumour uptake, tumour growth inhibition and improved survival. Radio- and fluorescence-labelled L19-SIP showed selective localisation and retention at vessels of two colorectal xenografts. Furthermore, 131I-L19-SIP shows potential as a novel treatment of colorectal tumours, and provides the foundation to investigate combined therapies in the same tumour models
Human monoclonal antibodies targeting carbonic anhydrase IX for the molecular imaging of hypoxic regions in solid tumours
BACKGROUND: Hypoxia, which is commonly observed in areas of primary tumours and of metastases, influences response to treatment. However, its characterisation has so far mainly been restricted to the ex vivo analysis of tumour sections using monoclonal antibodies specific to carbonic anhydrase IX (CA IX) or by pimonidazole staining, after the intravenous administration of this 2-nitroimidazole compound in experimental animal models.METHODS: In this study, we describe the generation of high-affinity human monoclonal antibodies (A3 and CC7) specific to human CA IX, using phage technology.RESULTS: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo. In one of the two animal models of colorectal cancer studied (LS174T), CA IX imaging closely matched pimonidazole staining, with a preferential staining of tumour areas characterised by little vascularity and low perfusion. In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting. We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies.CONCLUSION: The new human anti-CA IX antibodies are expected to be non-immunogenic in patients with cancer and may serve as broadly applicable reagents for the non-invasive imaging of hypoxia and for pharmacodelivery applications. British Journal of Cancer (2009) 101, 645-657. doi: 10.1038/sj.bjc.6605200 www.bjcancer.com Published online 21 July 2009 (C) 2009 Cancer Research U
Post-translational deregulation of YAP1 is genetically controlled in rat liver cancer and determines the fate and stem-like behavior of the human disease
Previous studies showed that YAP1 is over-expressed in hepatocellular carcinoma
(HCC). Here we observed higher expression of Yap1/Ctgf axis in dysplastic nodules and
HCC chemically-induced in F344 rats, genetically susceptible to hepatocarcinogenesis,
than in lesions induced in resistant BN rats. In BN rats, highest increase in Yap1-
tyr357, p73 phosphorylation and Caspase 3 cleavage occurred. In human HCCs with
poorer prognosis (< 3 years survival after partial liver resection, HCCP), levels of
YAP1, CTGF, 14–3–3, and TEAD proteins, and YAP1-14-3-3 and YAP1-TEAD complexes
were higher than in HCCs with better outcome (> 3 years survival; HCCB). In the
latter, higher levels of phosphorylated YAP1-ser127, YAP1-tyr357 and p73, YAP1
ubiquitination, and Caspase 3 cleavage occurred. Expression of stemness markers
NANOG, OCT-3/4, and CD133 were highest in HCCP and correlated with YAP1 and
YAP1-TEAD levels. In HepG2, Huh7, and Hep3B cells, forced YAP1 over-expression
led to stem cell markers expression and increased cell viability, whereas inhibition
of YAP1 expression by specific siRNA, or transfection of mutant YAP1 which does
not bind to TEAD, induced opposite alterations. These changes were associated, in
Huh7 cells transfected with YAP1 or YAP1 siRNA, with stimulation or inhibition of cell
migration and invasivity, respectively. Furthermore, transcriptome analysis showed
that YAP1 transfection in Huh7 cells induces over-expression of genes involved
in tumor stemness. In conclusion, Yap1 post-translational modifications favoring
its ubiquitination and apoptosis characterize HCC with better prognosis, whereas
conditions favoring the formation of YAP1-TEAD complexes are associated with
aggressiveness and acquisition of stemness features by HCC cells
Una ricerca sul disagio lavorativo nelle provincia di Cagliari in collaborazione con la CISL Sardegna
USE OF ULTRASOUND REAL-TIME EXAMINATION AND COLOUR-DOPPLER TO EVALUATE INITIAL RESPONSE TO ROOT CANAL TREATMENT
METALATION OF ARYLMETHYL METHYL ETHERS AND CONNECTION WITH THEIR REDUCTIVE ELECTROPHILIC SUBSTITUTION
Stable alpha-methoxy arylmethyl carbanions can be generated by metalation of arylmethyl methyl ethers, 1, with n-BuLi in THF at -40 degrees C, avoiding Wittig rearrangement to the corresponding alkoxides 2. Reaction of these carbanions with various electrophiles afforded the expected products 3 in satisfactory yields. Connection between the metalation procedure and the reductive electrophilic substitution of arylmethyl methyl ethers allowed the transformation of compounds 1 into 2-arylpropanoic acids,
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