A Comparison of the Effects of Silica and Hydroxyapatite Nanoparticles on Poly(e-caprolactone)-Poly(ethylene glycol)- Poly(e-caprolactone)/Chitosan Nanofibrous Scaffolds for Bone Tissue Engineering

Vahideh Raeisdasteh Hokmabad,Soodabeh Davaran,Marziyeh Aghazadeh,Effat Alizadeh,Roya Salehi,Ali Ramazani 한국조직공학과 재생의학회 2018 조직공학과 재생의학 Vol.15 No.6

BACKGROUND: The major challenge of tissue engineering is to develop constructions with suitable properties which would mimic the natural extracellular matrix to induce the proliferation and differentiation of cells. Poly(e-caprolactone)- poly(ethylene glycol)-poly(e-caprolactone) (PCL-PEG-PCL, PCEC), chitosan (CS), nano-silica (n-SiO2) and nano-hydroxyapatite (n-HA) are biomaterials successfully applied for the preparation of 3D structures appropriate for tissue engineering. METHODS: We evaluated the effect of n-HA and n-SiO2 incorporated PCEC-CS nanofibers on physical properties and osteogenic differentiation of human dental pulp stem cells (hDPSCs). Fourier transform infrared spectroscopy, field emission scanning electron microscope, transmission electron microscope, thermogravimetric analysis, contact angle and mechanical test were applied to evaluate the physicochemical properties of nanofibers. Cell adhesion and proliferation of hDPSCs and their osteoblastic differentiation on nanofibers were assessed using MTT assay, DAPI staining, alizarin red S staining, and QRT-PCR assay. RESULTS: All the samples demonstrated bead-less morphologies with an average diameter in the range of 190–260 nm. The mechanical test studies showed that scaffolds incorporated with n-HA had a higher tensile strength than ones incorporated with n-SiO2. While the hydrophilicity of n-SiO2 incorporated PCEC-CS nanofibers was higher than that of samples enriched with n-HA. Cell adhesion and proliferation studies showed that n-HA incorporated nanofibers were slightly superior to n-SiO2 incorporated ones. Alizarin red S staining and QRT-PCR analysis confirmed the osteogenic differentiation of hDPSCs on PCEC-CS nanofibers incorporated with n-HA and n-SiO2. CONCLUSION: Compared to other groups, PCEC-CS nanofibers incorporated with 15 wt% n-HA were able to support more cell adhesion and differentiation, thus are better candidates for bone tissue engineering applications.

The Effect of Melanocyte Stimulating Hormone and Hydroxyapatite on Osteogenesis in Pulp Stem Cells of Human Teeth Transferred into Polyester Scaffolds

Marziyeh Aghazadeh,Mohammad Samiei,Vahideh Raeisdasteh Hokmabad,Effat Alizadeh,Neda Jabbari,Alexander Seifalian,Roya Salehi 한국섬유공학회 2018 Fibers and polymers Vol.19 No.11

Presently, tissue engineering is employed in the restoration and repair of tissue defects. Degradable scaffolds, stem cells and stimulating factors are employed in this method. In this study, the effect of melanocyte-stimulating hormone (MSH) and/or hydroxyapatite (HA) on proliferation, osteoblast differentiation, and mineralization of human dental pulp stem cells (hDPSCs) seeded on PLLA-PCL nanofibrous scaffolds was evaluated. For this aim, PLLA-PCL-HA nanofibrous scaffolds were fabricated using electrospinning method. FE-SEM images exhibited that all nanofibers had bead-free morphologies with average diameters ranging from 150-205 nm. Human DPSCs seeded into PLLA-PCL nanofibers were treated with MSH. Cell viability, proliferation, morphology, osteogenic potential, and the expression of tissue-specific genes were assessed by means of MTT assay, FE-SEM, alizarin red S staining, and RT-PCR analysis. hDPSCs exhibited improved adhesion and proliferation capacity on the PLLA-PCL-HA nanofibers treated with MSH compared to other groups (p<0.05). Additionally, PLLA-PCL-HA nanofibers treated with MSH exhibited significantly higher mineralization and alkaline phosphatase activity than other groups. RT-PCR results confirmed that PLLA-PCL-HA nanofibers enriched with MSH could significantly unregulated the gene expression of BMP2, osteocalcin, RUNX2 and DSPP that correlated to osteogenic differentiation (p<0.05). Based on results, incorporation of HA nanoparticles in PLLA-PCL nanofibers and addition of MSH in media exhibited synergistic effects on the adhesion, proliferation, and osteogenesis differentiation of hDPSCs, and therefore assumed to be a favorable scaffold for bone tissue engineering applications.

Role of Endoscopic Ultrasound in Evaluation of Pancreatic Neuroendocrine Tumors - Report of 22 Cases from a Tertiary Center in Iran

Haghighi, Shirin,Molaei, Mahsa,Foroughi, Forough,Foroutan, Mojgan,Dabiri, Reza,Habibi, Effat,Alizadeh, Amir Houshang Mohammad Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Background: The pancreatic neuroendocrine tumor (pNET) is relatively rare and generally felt to follow an indolent course. EUS has an important role in detection of pNET. This is a review of clinical and radiological presentation and pathologic reports of 22 patients with pNET. Patients and methods: In this study we analyzed clinical and radiological presentations and pathologic reports of all relevant cases who were referred to Taleghani hospital for 3 years since 2008. Results: A total of 22 patients 28-74 years old (mean=49) were enrolled between 2008 and 2011. Among the total, 13 (59%) were male, 9 (41%) were female and 16 (72.7%) had functional tumors. The results of CT were negative in 12 (54%) cases but EUS was capable of detecting the lesions in these patients, cysts being found in 4 (19%) patients. Conclusion: EUS is a highly sensitive procedure for the localization of functional pNETs and especially insulinomas. Nonfunctional tumors were detected in more advanced and late stages and cystic lesions were more common in this group.

Trichostatin A-induced Apoptosis is Mediated by Krüppel-like Factor 4 in Ovarian and Lung Cancer

Zohre, Sadeghi,Kazem, Nejati-Koshki,Abolfazl, Akbarzadeh,Mohammad, Rahmati-Yamchi,Aliakbar, Movassaghpour,Effat, Alizadeh,Zahra, Davoudi,Hassan, Dariushnejad,Nosratollah, Zarghami Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Background: The istone deacetylase (HDAC) inhibitor trichostatin A (TSA) is known to mediate the regulation of gene expression and antiproliferation activity in cancer cells. Kr$\ddot{u}$ppel-like factor 4 (klf4) is a zinc finger-containing transcription factor of the SP/KLF family, that is expressed in a variety of tissues and regulates cell proliferation, differentiation, tumorigenesis, and apoptosis. It may either either function as a tumor suppressor or an oncogene depending on genetic context of tumors. Aims: In this study, we tested the possibility that TSA may increase klf4 expression and cancer cell growth inhibition and apoptosis in SKOV-3 and A549 cells. Materials and Methods: The cytotoxicity of TSA was determined using the MTT assay test, while klf4 gene expression was assessed by real time PCR andto ability of TSA to induce apoptosis using a Vybrant Apoptosis Assay kit. Results: Our results showed that TSA exerted dose and time dependent cytotoxicity effect on SKOV-3 and A549 cells. Moreover TSA up-regulated klf4 expression. Flow cytometric analysis demonstrated that apoptosis was increased after TSA treatment. Conclusions: Taken together, this study showed that TSA increased klf4 expression in SKOV3 and A549 cell lines, consequently, klf4 may played a tumor-suppressor role by increasing both cell growth inhibition and apoptosis. This study sheds light on the details of molecular mechanisms of HDACI-induced cell cycle arrest and apoptosis.

Inhibitory Effects of β-Cyclodextrin-Helenalin Complexes on H-TERT Gene Expression in the T47D Breast Cancer Cell Line - Results of Real Time Quantitative PCR

Ghasemali, Samaneh,Nejati-Koshki, Kazem,Akbarzadeh, Abolfazl,Tafsiri, Elham,Zarghami, Nosratollah,Rahmati-Yamchi, Mohamad,Alizadeh, Effat,Barkhordari, Amin,Tozihi, Majid,Kordi, Shirafkan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Background: Nowadays, the encapsulation of cytotoxic chemotherapeutic agents is attracting interest as a method for drug delivery. We hypothesized that the efficiency of helenalin might be maximized by encapsulation in ${\beta}$-cyclodextrin nanoparticles. Helenalin, with a hydrophobic structure obtained from flowers of Arnica chamissonis and Arnica Montana, has anti-cancer and anti-inflammatory activity but low water solubility and bioavailability. ${\beta}$-Cyclodextrin (${\beta}$-CD) is a cyclic oligosaccharide comprising seven D-glucopyranoside units, linked through 1,4-glycosidic bonds. Materials and Methods: To test our hypothesis, we prepared ${\beta}$-cyclodextrin-helenalin complexes to determine their inhibitory effects on telomerase gene expression by real-time polymerase chain reaction (q-PCR) and cytotoxic effects by colorimetric cell viability (MTT) assay. Results: MTT assay showed that not only ${\beta}$-cyclodextrin has no cytotoxic effect on its own but also it demonstrated that ${\beta}$-cyclodextrin-helenalin complexes inhibited the growth of the T47D breast cancer cell line in a time and dose-dependent manner. Our q-PCR results showed that the expression of telomerase gene was effectively reduced as the concentration of ${\beta}$-cyclodextrin-helenalin complexes increased. Conclusions: ${\beta}$-Cyclodextrin-helenalin complexes exerted cytotoxic effects on T47D cells through down-regulation of telomerase expression and by enhancing Helenalin uptake by cells. Therefore, ${\beta}$-cyclodextrin could be superior carrier for this kind of hydrophobic agent.