11^th Annual Conference on Stem Cell and Regenerative Medicine October 15-16, 2018 Amsterdam, Netherlands

Ghadeer Ibrahem Al-Refaei is a Lecturer at Biology Department, Faculty of Sciences, Jeddah University, Jeddah, Saudi Arabia. He is a PhD Student at Biology Department,rnKing Abdulaziz. His research interests are in embryology and stem cells culture. He is the Member in embryonic stem research unit at King Fahd Center for Medical Research.

Overexpression of Telomerase Reverse Transcriptase (TERT) is associated with increase inrntelomere length and its repression cause telomere shortening. The expression level of hTERT in human Fetal Membranes (hFM) is still not clearly established. As such we in the present studyrnevaluated the hTERT expression in human FM from three different age groups to understandrnif there exists any difference between them. Human fetal membranes (placental and umbilical cord) samples were collected following ethical approval and informed patient consent as follows, Group I: Young (20-29 years; n=15); Group II: Middle (30-39 years, n=16) and Group III: Oldrn(40-50 years, n=17). Total RNA was extracted from fresh FM and cDNA prepared. Real-time PCRrn(qRT-PCR) was performed to analyze hTERT expression levels. GAPDH was used as the internalrncontrols were analyzed using ΔΔCT method. In addition, hFM-MSCs were derived, establishedrnin culture and characterized for their stem-ness properties by CD marker expression(flowcytometry). The human fetal membranes collected from three different age groups yielded goodrnquantity and quality of RNA. qRT-PCR showed down regulation of hTERT expression in GrouprnII and Group III compared to Group I. There was a statistical decrease by -1.89 fold in Group II and -1.10 fold in Group III, compared to the control. Derived hFM-MSCs were plastic adherentrnand appeared as short thin fibroblasts. Flow-cytometry showed positive expression of CD73, CD105, CD90, CD29 and negative for CD34, CD45. Expression of hTERT levels showed significant deferentially expressed genes in each comparisons group with different age. However, comparison of hTERT levels at the cellular levels (isolated stem cells from hFM-MSCs are expected to provide additional insights. Identification of the expression levels of hTERT in stem cells will directly serve to indicate its life-span and replicative capacity, which will help with selection of the best cell type for use in regenerative medicine.

Muneerah A Huwaikem is a Masters student in the Department of Medical Laboratories Technology, Faculty of Applied Medical Sciences from King Abdulaziz University,\r\nKingdom of Saudi Arabia.

Background: Acute Myeloid Leukemia (AML) is most common in adults and is associated with rapid progression and high mortality with delayed treatment. Despite therapeutic advances, its prognosis remains poor in adults compared to the young. Mesenchymal Stem Cells (MSCs) are reported to have anti-cancer properties but their effects against AML are hitherto not reported. We in the present study evaluated the anticancer\r\nproperties of human umbilical cord mesenchymal stem cells (hUC-MSCs) against an AML cell line\r\n(K562) in vitro using co-culture system.\r\n\r\nMethods: Human umbilical cords were collected following Institutional Ethical Committee approval [a33-15/KAU]. hUC-MSCs were derived using explant culture method and K562 was obtained from ATCC. Both hUC-MSCs and AML cells were cultured under standard culture conditions and\r\nrespective cell proliferation assessed. Derived hUC-MSCs were characterized for their stemness\r\nusing cell morphology and MSCs related CD markers expression (FACS). Anti-cancer effects of\r\nhUC-MSCs were evaluated by co-culture with AML cells plated at equal seeding density (2×104\r\ncells/well) in a 24-well plate followed by culture for 24h, 48h and 72h. Changes in cell morphology and cell proliferation (MTT assay) were assessed.\r\nResult: Derived hUC-MSCs were plastic adherent and showed short fibroblastic morphology\r\nresembling MSCs. K562 cells showed spherical morphology like undifferentiated blast cells. hUCMSCs were positive for CD73, CD105, CD29 and CD90 while they were negative for CD34, CD45.\r\nIn co-culture, K562 cells clustered onto the hUC-MSCs and showed signs of cell death. K562 also demonstrated statistical decrease in cell proliferation by 2.03%, 36.92% and 16.38% at 24h, 48h and 72h, respectively compared to the untreated control.\r\n\r\nConclusion: hUC-MSCs induced inhibition of K562 cells in vitro. Inhibitory effect on cell proliferation indicates that hUC-MSCs have anti-cancer effects. Additional studies using cell free extracts of hUC-MSCs to evaluate AML inhibition will help to elucidate the underlying anticancer mechanism.