Goat tendon collagen-human fibrin hydrogel for comprehensive parametric evaluation of HUVEC microtissue-based angiogenesis.

The cell and extracellular matrix (ECM) interactions play a very important role during angiogenesis. Remodeling of the extracellular matrix along with pro-angiogenic/anti-angiogenic factors, and matrix-degrading proteases, accounts for endothelial cell growth, migration, and tube formation. However, for studying angiogenesis, only limited and expensive biomaterials are available. Despite being biocompatible, inexpensive, and easy availability; the potential of goat tendon collagen (GTC) has never been explored for vascular tissue engineering applications. Hence, the current investigation was focused on evaluating GTC as an alternative matrix for HUVEC microtissue-based angiogenesis. HUVEC microtissues (MTs), synthesized via hanging drop method, were subjected to angiogenesis in GTC-human fibrin (HF) hydrogels. Sprouting tip cells originated from the MTs within 24 h. Further, comprehensive in vitro study and in vivo validation revealed that, endothelial media with FBS and growth factors, 24 h old HUVEC MTs of 500 cells, seeded at 200 aggregates/cm3 in GTC-HF gel of 100 Pa elastic modulus, resulted in most optimal angiogenesis with intact lumen that was stable up to a week, without any supporting cells. Although early to predict, GTC-HF matrix may serve as a potential ECM for engineering complex and functional tissues of clinical relevance.

Decellularized caprine liver extracellular matrix as a 2D substrate coating and 3D hydrogel platform for vascularized liver tissue engineering.

Development of a vascularized liver tissue construct is a need of an hour to circumvent the current demand of liver transplantation in health care sector. An appropriate matrix must support liver cell viability, functionality, and development of microvasculature. With this perspective, here, we report the use of decellularized caprine liver extracellular matrix (CLECM) derived hydrogel for tissue engineering applications. First, CLECM was used as a substrate coating material for 2D hepatocyte culture. HepG2 cells cultured on CLECM-coated surface showed higher albumin, urea, glycogen, and GAGs synthesis in comparison with collagen-coated surface (taken as control for the study). Thereafter, the cells were encapsulated in CLECM hydrogels for 3D culture. In CLECM hydrogels, HepG2 cells showed highly differentiated and polarized phenotype with the appearance of bile canaliculi-like structures and enhanced expression of mature hepatocyte markers. We further showed that CLECM hydrogels also supported the development of microvasculature in vitro, thus making it a suitable candidate for development of a prevascularized liver tissue construct. In conclusion, we proved the superiority of CLECM over collagen for 2D/3D human hepatocyte and endothelial cell culture. CLECM could serve as an efficient biomaterial platform in the development of a liver tissue construct for application in tissue engineering.

Ectopic vascularized bone formation by human mesenchymal stem cell microtissues in a biocomposite scaffold.

Three-dimensional multicellular human bone marrow mesenchymal stem cells (hBM-MSCs) are showing a great promise in the repair of bone tissue due to its osteogenic differentiation potential, mimicking in vivo microenvironment and immunomodulatory property. In the present study, the potential of hBM-MSC microtissues (MTs) in combination with a biocomposite material to form vascularized bone-like tissue at an ectopic site in an immunocompromised mouse was evaluated. The scaffold was fabricated using gelatin, carboxymethyl cellulose, polyvinyl alcohol and nano-hydroxyapatite (GCnHP) by the freeze-drying method. The physico-chemico-biological characteristics were compared with control scaffold devoid of polyvinyl alcohol (GCnH). The scaffolds (GCnH and GCnHP) were highly porous and had interconnected pores. GCnHP showed higher mechanical strength, higher water adsorption and a lower rate of collagenase-mediated degradation in comparison to GCnH. The scaffolds also supported growth and proliferation of hBM-MSCs MTs and subsequent differentiation into osteoblast-like cells. The differentiated cells showed matrix mineralization and high expression of runX2, alkaline phosphatase, collagen type 1 and osteocalcin genes. A high expression of VEGF was also observed suggesting the potential of hBM-MSC MTs to induce angiogenesis. H&E and Masson's trichrome staining of the 4-weeks in vivo implanted scaffold revealed the presence of newly synthesized collagen and infiltration of host vasculature. IHC assessment showed expression of osteocalcin and osterix. These results demonstrate the efficacy of the combination of hBM-MSC MTs and biocomposite material as a promising approach for in vivo non-load bearing bone tissue repair for future clinical and various regenerative medicine applications.

Real-World Treatment Patterns among Patients with Advanced Gastric Cancer in South Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to understand patient treatment patterns, outcomes, and healthcare resource use in cases of metastatic and/or locally recurrent, unresectable gastric cancer (MGC) in South Korea. MATERIALS AND METHODS: Thirty physicians reviewed charts of eligible patients to collect de-identified data. Patients must have received platinum/fluoropyrimidine first-line therapy followed by second-line therapy or best supportive care, had no other primary cancer, and not participated in a clinical trial following MGC diagnosis. Data were summarized using descriptive statistics. Kaplan-Meier analysis was used to describe survival. RESULTS: Of 198 patients, 73.7% were male, 78.3% were diagnosed with MGC after age 55 (mean, 61.3 years), and 47.0% were current or former smokers. The majority of tumorswere located in the antrum/pylorus (51.5%). Metastatic sites most often occurred in the peritoneum (53.5%), lymph nodes (47.5%), and liver (38.9%). At diagnosis, the mean Charlson comorbidity indexwas 0.4 (standard deviation, 0.6). The most common comorbidities were chronic gastritis (22.7%) and cardiovascular disease (18.7%). Most patients (80.3%) received second-line treatment. Single-agent fluoropyrimidine was reported for 22.0% of patients, while 19.5% were treated with irinotecan and a fluoropyrimidine or platinum agent. The most common physician-reported symptoms during second-line treatment were nausea/vomiting (44.7%) and pain (11.3%), with antiemetics (44.7%), analgesics (36.5%), and nutritional support (11.3%) most often used as supportive care. Two-thirds of inpatient hospitalizations were for chemotherapy infusion. Outpatient hospitalization (31.6%) and visits to the oncologist (58.8%) were common among second-line patients. CONCLUSION: Most patients received second-line treatment, although regimens varied. Understanding MGC patient characteristics and treatment patterns in South Korea will help address unmet needs.

Gelatin/Carboxymethyl chitosan based scaffolds for dermal tissue engineering applications.

The present study delineates the preparation, characterization and application of gelatin-carboxymethyl chitosan scaffolds for dermal tissue engineering. The effect of carboxymethyl chitosan and gelatin ratio was evaluated for variations in their physico-chemical-biological characteristics and drug release kinetics. The scaffolds were prepared by freeze drying method and characterized by SEM and FTIR. The study revealed that the scaffolds were highly porous with pore size ranging between 90 and 170µm, had high water uptake (400-1100%) and water retention capacity (>300%). The collagenase mediated degradation of the scaffolds was dependent on the amount of gelatin present in the formulation. A slight yet significant variation in their biological characteristics was also observed. All the formulations supported adhesion, spreading, growth and proliferation of 3T3 mouse fibroblasts. The cells seeded on the scaffolds also demonstrated expression of collagen type I, HIF1α and VEGF, providing a clue regarding their growth and proliferation along with potential to support angiogenesis during wound healing. In addition, the scaffolds showed sustained ampicillin and bovine serum albumin release, confirming their suitability as a therapeutic delivery vehicle during wound healing. All together, the results suggest that gelatin-carboxymethyl chitosan based scaffolds could be a suitable matrix for dermal tissue engineering applications.

Abrus precatorius agglutinin-derived peptides induce ROS-dependent mitochondrial apoptosis through JNK and Akt/P38/P53 pathways in HeLa cells.

10kDAGP, a tryptic digest of Abrus precatorius lectin 'Agglutinin' is known to induce apoptosis by mitochondria-dependent pathways in human cervical cancer (HeLa) cells. The present study was focused on deciphering the detailed molecular mechanism of apoptosis induction in vitro by 10kDAGP and also its in vivo therapeutic efficacy. For in vivo model, HeLa cell encapsulated hollow fiber was implanted in Swiss Albino mice and treated with 10kDAGP. Our results showed that 10kDAGP was able to enter the cell within a span of 20min and co-localized with mitochondria after 90min. of incubation. A drastic loss of mitochondrial membrane potential was noted within 6h of 10kDAGP administration along with an increase in ROS generation. ROS further led to symptoms of early apoptosis by deregulating Akt (Protein Kinase B) and activating c-Jun N-terminal Kinase (JNK), p38 Mitogen Activated Protein Kinase (MAPK), p53, and autophagy starting from ∼8h of incubation. Besides in vitro conditions, 10kDAGP activated JNK to mediate cancer cell killing in vivo. Therefore, 10kDAGP can be an excellent therapeutic agent as it can act through different ways in the cellular system. Future studies are directed to screen out active peptides from the pool of peptides and to study whether the mode of action is in synergistic way or in individual forms.

Multifunctional mesoporous hollow silica nanocapsules for targeted co-delivery of cisplatin-pemetrexed and MR imaging.

The development of theranostic mesoporous hollow silica nanospheres having therapeutic and diagnostic functions has been achieved. The exterior surface of the hollow mesoporous silica nanosphere was selectively acid functionalized and utilised to conjugate the anticancer drug cisplatin, the marker molecule folic acid (FA), and rhodamine isothiocyanate (RITC), whereas the interior space was utilised to encapsulate superparamagnetic CoFe2O4 nanoparticles as well as the hydrophobic anticancer drug pemetrexed. The hydrodynamic size of the synthesized multidrug loaded hollow particles is 130 nm in physiological pH and it is consistent over a long period. To the best of our knowledge this is the first report on fluorescent magnetic hollow spheres loaded with multiple therapeutic cargoes as well as a magnetic resonance imaging (MRI) contrast agent. The as prepared hollow spheres are biocompatible. The internalization efficiency of the drug loaded particle has been evaluated on folate receptor overexpressed (FR+ve) HeLa, FR-ve HaCat and 3T3 cells. These drug loaded nanospheres exhibit enhanced cytotoxicity as compared to individual drugs. Such a strategy in the simultaneous administration of pemetrexed and platin drugs may open up opportunities for the treatment of lung cancer at its early stage.

Nanocomposites of bio-based hyperbranched polyurethane/funtionalized MWCNT as non-immunogenic, osteoconductive, biodegradable and biocompatible scaffolds in bone tissue engineering.

This study focused on the design of novel mechanically tough, biocompatible, osteoconductive and biodegradable scaffolds based on sunflower oil modified hyperbranched polyurethane (HBPU)/functionalized multi-walled carbon nanotube (f-MWCNT) nanocomposites (NCs), and the response of an animal model on their post-implantation. The NC was prepared by an in situ polymerization technique with different wt% of f-MWCNTs. The tensile strength of the NCs was enhanced to 36.98-47.6 MPa from 23.93 MPa (HBPU) and toughness from 12 767 to 18 427-19 440 due to the addition and efficient dispersion of the f-MWCNTs in the HBPU matrix. The post-60 days in vitro biodegraded NC retained sufficient strength (39 ± 1.65 MPa). The increase in wt% of f-MWCNTs had a significant effect on tailoring the physico-mechanical properties of the polymer. The hematological, histological and immunological indices of toxicity suggested the safety potential of the prepared systems within the tested animal model. Moreover, the cytokines (viz. IL-6 and TNF-α) detection, MTT assay and anti-hemolytic assay boosted the non-toxic behavior of the systems. The NC with interconnected pores size (200-330 µm) showed better proliferation and adherence of osteoblast (MG63) cells compared to the HBPU and the results were comparable with the control. Thus the findings confirmed the non-toxicity of f-MWCNTs in association with the polymer and thereby endorsed the NC as a potential biomimetic scaffold for bone tissue engineering.