The anticancer activity of a methanolic extract from lemon leaves (MLL) was assessed in MCF-7-SC human breast cancer stem cells. MLL induced apoptosis in MCF-7-SC, as evidenced by increased apoptotic body formation, sub-G1 cell population, annexin V-positive cells, Bax/Bcl-2 ratio, as well as proteolytic activation of caspase-9 and caspase-3, and degradation of poly (ADP-ribose) polymerase (PARP) protein. Concomitantly, MLL induced the formation of acidic vesicular organelles, increased LC3-II accumulation, and reduced the activation of Akt, mTOR, and p70S6K, suggesting that MLL initiates an autophagic progression in MCF-7-SC via the Akt/mTOR pathway. Epithelial-mesenchymal transition (EMT), a critical step in the acquisition of the metastatic state, is an attractive target for therapeutic interventions directed against tumor metastasis. At low concentrations, MLL induced anti-metastatic effects on MCF-7-SC by inhibiting the EMT process. Exposure to MLL also led to an increase in the epithelial marker E-cadherin, but decreased protein levels of the mesenchymal markers Snail and Slug. Collectively, this study provides evidence that lemon leaves possess cytotoxicity and anti-metastatic properties. Therefore, MLL may prove to be beneficial as a medicinal plant for alternative novel anticancer drugs and nutraceutical products.
Kim, Jin Sook;You, Da-Bin;Lim, Ji-Young;Lee, Sung-Eun;Kim, Yoo-Jin;Kim, Hee-Je;Chung, Nack-Gyun;Min, Chang-Ki
IMMUNE NETWORK
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v.15
no.2
/
pp.66-72
/
2015
Currently, detecting biochemical differences before and after allogeneic stem cell transplantation (SCT) for improved prediction of acute graft-versus-host disease (aGVHD) is a major clinical challenge. In this pilot study, we analyzed the kinetics of circulating adipokine levels in patients with or without aGVHD before and after allogeneic SCT. Serum samples were obtained and stored at $-80^{\circ}C$ within 3 hours after collection, prior to conditioning and at engraftment after transplantation. A protein array system was used to measure the levels of 7 adipokines of patients with aGVHD (n=20) and without aGVHD (n=20). The resistin level at engraftment was significantly increased (p<0.001) after transplantation, regardless of aGVHD occurrence. In the non-aGVHD group, the concentrations of the hepatocyte growth factor (HGF) (mean values${\pm}$SD; $206.6{\pm}34.3$ vs. $432.3{\pm}108.9pg/ml$, p=0.040) and angiopoietin-2 (ANG-2) (mean values${\pm}$SD; $3,197.2{\pm}328.3$ vs. $4,471.8{\pm}568.4pg/ml$, p=0.037) at engraftment were significantly higher than those of the pre-transplant period, whereas in the aGVHD group, the levels of adipokines did not change after transplantation. Our study suggests that changes in serum HGF and ANG-2 levels could be considered helpful markers for the subsequent occurrence of aGVHD.
Background: Cytokine-mediated ex vivo expansion has been proposed as a means of increasing the number of cord blood (CB) hematopoietic stem cells for transplantation. As well as stem cell number, stromal cells are necessary for functional maturation of hematopoiesis. The purpose of this study was to analyze the development of stromal cells during ex vivo expansion of CB $CD34^+$ cells. Methods : $CD34^+$ cells were purified from CB by magnetic bead selection. The levels of of interleukin-3, interleukin-$1{\beta}$, interleukin-6, granulocyte macrophagecolony stimulating factor and tumor necrosis factor-${\alpha}$ were measured in culture supernatants on 0, 1, 2, and 3 weeks, using ELISA techniques. CB $CD34^+$ cells were expanded in Iscoves modified Dulbeccos medium in the presence of several cytokines. The expression of E-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, platelet/endothelial cell adhesion molecule-1, von Willebrand factor, vimentin, and CD14 in newly developed stromal cells was examined by immunocytochemical method. Relevant extracellular matrix (ECM) proteins and proper cytokines were also assayed for the most suitable condition for expansion of stromal cells. Results: Several cytokines were found to have been produced by CB $CD34^+$ cells as well as bone marrow-derived $CD34^+$ cells. During ex vivo expansion of CB $CD34^+$ cells, stromal cells appeared in the culture by day 4 and expanded over the following 7-10 days before being confluent by day 2 1. These cells expressed surface markers characteristic of cells of endothelial lineage. Furthermore, these stroaml cells also expanded effectively when treated with thrombopoietin+flt-3 ligand+stem cell factor+leukemia inhibitory factor or 0.1% poly-L-lysine-coated wells. Conclusion: Stromal cells were developed during ex vivo expansion of CB $CD34^+$ cells and that this development could be enhanced further by treating the stromal cells with cytokines or ECM.
Purpose: Adipose tissue is located beneath the skin, around internal organs, and in the bone marrow in humans. Its main role is to store energy in the form of fat, although it also cushions and insulates the body. Adipose tissue also has the ability to dynamically expand and shrink throughout the life of an adult. Recently, it has been shown that adipose tissue contains a population of adult multipotent mesenchymal stem cells and endothelial progenitor cells that, in cell culture conditions, have extensive proliferative capacity and are able to differentiate into several lineages, including, osteogenic, chondrogenic, endothelial cells, and myogenic lineages. Materials and Methods: This study focused on endothelial cell culture from the adipose tissue. Adipose tissues were harvested from buccal fat pad during bilateral sagittal split ramus osteotomy for surgical correction of mandibular prognathism. The tissues were treated with 0.075% type I collagenase. The samples were neutralized with DMEM/and centrifuged for 10 min at 2,400 rpm. The pellet was treated with 3 volume of RBC lysis buffer and filtered through a 100 ${\mu}m$ nylon cell strainer. The filtered cells were centrifuged for 10 min at 2,400 rpm. The cells were further cultured in the endothelial cell culture medium (EGM-2, Cambrex, Walkersville, Md., USA) supplemented with 10% fetal bovine serum, human EGF, human VEGF, human insulin-like growth factor-1, human FGF-$\beta$, heparin, ascorbic acid and hydrocortisone at a density of $1{\times}10^5$ cells/well in a 24-well plate. Low positivity of endothelial cell markers, such as CD31 and CD146, was observed during early passage of cells. Results: Increase of CD146 positivity was observed in passage 5 to 7 adipose tissue-derived cells. However, CD44, representative mesenchymal stem cell marker, was also strongly expressed. CD146 sorted adipose tissue-derived cells was cultured using immuno-magnetic beads. Magnetic labeling with 100 ${\mu}l$ microbeads per 108 cells was performed for 30 minutes at $4^{\circ}C$ a using CD146 direct cell isolation kit. Magnetic separation was carried out and a separator under a biological hood. Aliquous of CD146+ sorted cells were evaluated for purity by flow cytometry. Sorted cells were 96.04% positivity for CD146. And then tube formation was examined. These CD146 sorted adipose tissue-derived cells formed tube-like structures on Matrigel. Conclusion: These results suggest that adipose tissue-derived cells are endothelial cells. With the fabrication of the vascularized scaffold construct, novel approaches could be developed to enhance the engineered scaffold by the addition of adipose tissue-derived endothelial cells and periosteal-derived osteoblastic cells to promote bone growth.
Background: Colon cancer (CRC) is perhaps the second most common cause of cancer mortality. This study determined the clinical significance of serum vascular endothelial growth factor (VEGF) and serum complement 3a (C3a) levels in patients with CRC in Fars province, southern Iran. Materials and Methods: Between June 2010 and June 2012, 110 patients with CRC of both genders and different age groups were divided into 3 groups. Group A included patients who had just undergone surgery; Group B had undergone chemotherapy after surgery; and Group C had undergone chemotherapy and radiotherapy after surgery. Twenty one healthy subjects with normal colonoscopy were considered as a control group. ELISA was undertaken to determine VEGF and C3a levels before and after treatment measures. Results: The mean age of patients was $53.9{\pm}14.1$ years. Considering VEGF level, a significant decrease was visible after treatment measures in groups A and B, but not Group C. For VEGF level, the difference was not statistically significant between two genders and various age groups before and after treatment. No significant difference was found for VEGF level between patients and normal group before any treatment. Regarding C3a levels in 101 subjects, they significantly decreased after treatment measures. Before and after treatment, the difference was statistically significant between two genders, but was not statistically significant among various age groups. Conclusions: As VEGF and C3a levels were significantly lower in patients after treatment, these may be beneficial markers in assessment of CRC therapy especially in early stages.
The cure rate of acute lymphoblastic leukemia (ALL) in children dramatically improved over past 5 decades from zero to about 80%. The main cause of improvement is owing to the development of chemotherapy by multicenter clinical trial of large study groups with the understanding of leukemia biology. Recently, pediatric ALL protocols were applied to the treatment of adolescent and even adult ALL patients. For nearly 30 years, clinical factors have been used to risk-stratify therapy for children with ALL, so that the most intensive therapies are reserved for those patients at the highest risk of relapse. The risk groups of ALL are divided as standard- (low- plus intermediate-), high- and very high-risk group according to the prognostic factors, and treatment results improved by this risk based treatment. The factors used to risk-stratify therapy include age, gender, presenting leukocyte count, immunophenotype, cytogenetic aberrations including ploidy and translocations, and initial response after 1 to 2 weeks of therapy. But treatment efficacy is the most important determinant and can abolish the clinical significance of most, if at all, prognostic factors. Today, in the era of intensive, multiagent regimens, there is increasing evidence that we have reached the limits of prognostic significance of currently applied clinical risk factors in childhood ALL. As the cure rate of ALL is about 80%, introducing new prognostic factors such as new molecular prognostic markers, new methods of assessment about minimal residual disease, and pharmacogenetic study, with the development of stem cell transplantation and molecular targeted therapy are needed to cure residual 20% of childhood ALL patients without short and long term complications.
As a preclinical study, many researchers have been attempted to convert the porcine PSCs into several differentiated cells with transplantation of the differentiated cells into the pigs. Here, we attempted to derive neuronal progenitor cells from pig embryonic germ cells (EGCs). As a result, neuronal progenitor cells could be derived directly from pig embryonic germ cells through the serum-free floating culture of EB-like aggregates (SFEB) method. Treating retinoic acid was more efficient for inducing neuronal lineages from EGCs rather than inhibiting SMAD signaling. The differentiated cells expressed neuronal markers such as PAX6, NESTIN, and SOX1 as determined by qRT-PCR and immunostaining. These data indicated that pig EGCs could provide valid models for human therapy. Finally, it is suggested that developing transgenic pig for disease models as well as differentiation methods will provide basic preclinical data for human regenerative medicine and lead to the success of stem cell therapy.
Kim, Jung-Ae;Ahn, Byul-Nim;Oh, Jung Hwan;Karadeniz, Fatih;Lee, Jung Im;Seo, Youngwan;Kong, Chang-Suk
Ocean and Polar Research
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v.44
no.1
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pp.29-38
/
2022
Halophytes are plants that live in harsh environments in coastal regions and are known for their diverse chemical compositions. Limonium tetragonum, a halophyte endemic to Korean shores, is known for its bioactive compounds and is utilized in folk medicine. In this study L. tetragonum extract (LHE) was used to determine and evaluate its anti-osteoporotic properties. Pre-adipocyte and pre-osteoblasts were induced to differentiate along with LHE treatment, and their differentiation was evaluated using differentiation markers. LHE treatment decreased lipid accumulation in 3T3-L1 preadipocytes during adipogenesis. Results indicated that the LHE treatment also decreased the levels of key adipogenic transcription factors: PPARγ, SREBP1c, and C/EBPα. Enhancing osteoblastogenesis by LHE treatment was confirmed in osteoblastogenesis-induced MC3T3-E1 pre-osteoblasts. Cells treated with LHE resulted in increased calcification and alkaline phosphatase (ALP) activity compared with osteoblasts without LHE treatment. Pro-osteogenic and anti-adipogenic effects were also confirmed in D1 murine mesenchymal stromal cells which are capable of differentiation into both adipocytes and osteoblasts. LHE hindered adipogenesis and enhanced osteoblastogenesis in D1 MSCs in a similar fashion. In conclusion, L. tetragonum is believed to possess the potential to be utilized as a nutraceutical ingredient against osteoporotic conditions.
Human mesenchymal stem cells(hMSC), that have been reported to be present in bone marrow, adipose tissues, dermis, muscles and peripheral blood, have the potential to differentiate along different lineages including those forming bone, cartilage, fat, muscle and neuron. Therefore, hMSC are attractive candidates for cell and gene therapy. The optimal conditions for hMSC expansion require medium supplemented with fetal bovine serum(FBS). Some forms of cell therapy will involve multiple doses, raising a concern over immunological reactions caused by medium-derived FBS proteins. Previously, we have shown that hADSC can be cultured in human serum(HS) during their isolation and expansion, and that they maintain their proliferative capacity and ability for multilineage differentiation and promote engraftment of peripheral blood-derived CD34 cells mobilized from bone marrow in NOD/SCID mice. In this study we determined whether hADSC grown in HS maintain surface markers expression similar with cells grown in FBS during culture expansion and compared gene expression profile by Affymetrix microarray. Flow cytometry analysis showed that HLA-DR, CD117, CD29 and CD44 expression in HS-cultured hADSC during culture expansion were similar with that in FBS-cultured cells. However, the gene expression profile in HS-cultured hADSC was significantly different from that in FBS-cultured cells. Therefore, these data indicated that HS-cultured hADSC should be used in vivo animal study of hADSC transplantation for direct extrapolation of preclinical data into clinical application.
Jo, Hannah;Eom, Young Woo;Kim, Hyun-Soo;Park, Hong Jun;Kim, Hee Man;Cho, Mee-Yon
Gut and Liver
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v.12
no.6
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pp.664-673
/
2018
Background/Aims: Regulatory dendritic cells (rDCs), which can be induced by mesenchymal stem cells (MSCs), play an important role in inducing and maintaining homeostasis of regulatory T cells and exhibit anti-inflammatory functions. In this study, we investigated whether MSCs could differentiate DCs into rDCs and compared the therapeutic effects of rDCs and MSCs on dextran sodium sulfate (DSS)-induced chronic colitis mice. Methods: Immature DCs (imDCs) and lipopolysaccharide (LPS)-treated mature DCs (mDCs) were co-cultured with MSCs for 48 hours, and then the profiles of surface markers and cytokines and regulatory roles of these DCs for primary splenocytes were analyzed. In addition, the therapeutic effects of MSCs and DCs co-cultured with MSCs were compared in chronic colitis mice. Results: After co-culture of imDCs (MSC-DCs) or LPS-treated mDCs (LPS+MSC-DCs) with MSCs, the expression of CD11c, CD80, CD86, interleukin 6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interferon-${\gamma}$ (IFN-${\gamma}$), was decreased, but that of CD11b, IL-10, and transforming growth factor-${\beta}$ (TGF-${\beta}$) was increased. Furthermore, MSC-DCs and LPS+MSC-DCs induced the expression of CD4, CD25, and Foxp3 in primary splenocytes isolated from mice. In DSS-induced colitis mice, MSCs and MSC-DCs increased colon length, body weight, and survival rate and induced histological improvement. Moreover, in the colon tissues, the expression of IL-6, TNF-${\alpha}$, and IFN-${\gamma}$ decreased, but that of IL-10, TGF-${\beta}$, and Foxp3 increased in the MSC- and MSC-DC-injected groups. Conclusions: Our data suggest that MSCs differentiate DCs into rDCs, which ameliorate chronic colitis. Thus, rDCs stimulated by MSCs may be therapeutically useful for the treatment of chronic inflammatory diseases.
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