Avicenna Journal of Medical Biotechnology
Year:2014 | Volume:6 | Issue:4|Papers Count:8

In the past, disease diagnosis was based on symptoms that might be indicative of several diseases. Nowadays, diagnosis of some diseases has become more accurate because we are able to test for genes known to be associated with the disease. This method not only clearly identifies the presence of a particular disease; it can also precisely determine the subtype of the disease. Throughout history, the practice of medicine has largely been reactive. Even now days, we have to wait until the onset of diseases and then try to treat or cure them. As we don’t fully understand the genetic and environmental factors that cause major diseases such as cancer, Alzheimer’s and diabetes, our efforts to treat them are often imprecise, unpredictable and ineffective.In addition, the drugs and treatments we devise are tested on broad populations and are prescribed using statistical averages.

Vascular endothelial growth factor (VEGF-A) is one of the most important regulatory factors in pathological and physiological angiogenesis. Alternative splicing is a complicated molecular process in VEGF-A gene expression which adds complexity to VEGF-A biology. Among all VEGF-A exons, alternative splicing of exon 8 is the key determinant of isoform switching from pro-angiogenic VEGF-xxx to anti-angiogenic VEGF-xxxb. This is known as a key molecular switching in many pathological situations. In fact, the balance between VEGF-xxx and VEGF-xxxb isoforms is a critical controlling switch in both conditions of health and disease. Here, the properties of VEGF-xxx and VEGFxxxb isoforms were discussed and their regulatory mechanism and their roles in certain pathological processes were evaluated. In summary, it was suggested that C-terminal VEGF-A alternative splicing can provide a new treatment opportunity in angiogenic diseases.

Background: Telomerase activity increases in cancer cells. Bcl-2 is an antiapoptotic factor that its concentration grows in many cancer cells including hepatocellular carcinoma cells. In this study, an attempt was made to investigate the effects of a new synthetic compound, platinum azidothymidine (Pt-AZT) on treatment of rats with Hepatocellular Carcinoma (HCC) and to compare its effects with azidothymidine (AZT) in alteration of telomerase activity and Bcl-2 concentration in HCC.Methods: Healthy adult male Wistar rats (n=100) were randomly divided into 4 groups (A, B, C, and D). Group A contained 25 healthy rats and was considered as the control group. Liver preneoplastic lesions were induced in remaining animals (n=75) using Solt-Farber resistant hepatocyte protocol. These animals were randomly allocated in groups B, C and D. Group B was negative control (untreated), groups C and D were treated by intraperitoneal injection (IP) of Pt-AZT (0.9 mg/kg/day) and AZT (0.3 mg/kg/day), respectively for 14 days. After the treatment period, telomerase activity and Bcl-2 concentration were determined in the rats’ liver.Results: No HCC was developed in group A, but tumors were present in all other groups. Telomerase activity and Bcl-2 concentration were significantly lower in group C compared to groups B (0.159±0.06 vs.0.577±0.116 IU/L, p<0.001, respectively and 0.931±0.388 vs.3.94±0.74 ng/ml, p<0.001, respectively). Similar results were observed in comparison with group D (0.331±0.06 vs.0.577±0.116 IU/L, p<0.001, respectively and 0.931±0.388 vs.2.94±0.594 ng/ml, respectively). There was a significant negative correlation between telomerase activity and Bcl-2 concentration only in untreated cancer group (p=0.034).Conclusion: In this study, higher anticancer activity of Pt-AZT in comparison to AZT was demonstrated. It effectively inhibits the growth of liver tumor in rats through extending apoptosis.

Background: The objective of this study was to investigate the effect of vitrification and in vitro maturation on the mitochondrial distribution and ATP content of oocytes.Methods: The oocytes at Germinal Vesicle (GV) and Metaphase II (MII) stages were recovered from 6-8 week old NMRI strain female mice. The oocytes were divided into vitrified and non-vitrified groups. Vitrification was done by the cryotop method using ethylene glycol, dimethylsulfoxide and sucrose as cryoprotectants.The GV oocytes were cultured in maturation medium for 24 hrs.The collected in vitro matured oocytes (IVM-MII) and ovulated metaphase II (OV-MII) oocytes were inseminated with capacitated sperm. The ATP content of the oocytes was measured by luciferin-luciferase reaction. Distribution of oocyte mitochondria was studied using Mito Tracker Green staining under fluorescent microscope.Results: The survival rates of vitrified oocytes at GV and MII stages were 87.39 and 89.5%, respectively. There was no significant difference in the developmental and hatching rates of vitrified and non-vitrified oocytes. The ATP content of GV and MII oocytes derived from in vivo and in vitro condition was not significantly different in vitrified and non-vitrified samples. The pattern of mitochondrial distribution in vitrified and non-vitrified GV and MII oocytes was similar but it was different between MII oocytes collected from fallopian tube and in vitro matured MII oocytes. However, the florescent intensity of mitochondrial staining was different in all the groups in the study.Conclusion: Vitrification did not affect mouse oocyte developmental competence, ATP content at different developmental stages but some alteration was seen in mitochondria distribution of in vitro matured oocytes in comparison to their controls.

Background: Mesenchymal Stem Cells (MSCs) are multipotent cells that can be collected from different sources. Under specific conditions, MSCs can be differentiated to tissue specific cells in vitro. Human Umbilical Cord Mesenchymal Stem Cells (hUCMSCs) can easily be harvested and cultured in in vitro conditions. Production of germ cells from mesenchymal stem cells is a very interesting and promising area in the field of reproductive medicine. In the present study, the possible trans-differentiation of hUCMSCs into Primordial like Germ Cell (PGC) was performed in vitro under specific condition.Methods: Human umbilical cord mesenchymal stem cells were cultured and expanded in DMEM medium containing 10% FBS. The cultured cells were studied for differentiation ability to adipocytes and osteocytes. Furthermore, MSCs related markers were identified by flow cytometry method. For PGC differentiation, hUCMS cells were cultured in differentiation medium containing Bone Morphogenetic Protein 4 (BMP4) and it was followed by retinoic acid (RA). Real time PCR and immunocytochemistry analysis were performed to evaluate the expression of PGC specific genes and proteins, respectively.Results: Our results showed that hUCMSCs cultured in the presence of BMP4 and RA are able to transdifferentiate in to PGC like cells in vitro. Real time PCR and immunocytochemistry results showed that differentiated cells expressed PGC specific markers after 14 days of culture.Conclusion: Based on these results, it was concluded that hUCMSC may be considered as a promising alternative cell source in reproductive medicine.More studies including laboratory and also animal models are needed to evaluate the functionality of differentiated PGCs before introducing them to clinical applications.

Background: Genes for human epidermal growth factor receptors B1 (ErbB1) and B2 (ErbB2) were amplified in breast and ovarian cancers. Both of them were associated with aggressive disease and worse prognosis. The ErbB1 or ErbB2 status of a tumor may provide an indication of the response to ErbB1 and ErbB2 -targeted therapies. For accurate and rapid assessment of amplification of ErbB1 and ErbB2 oncogenes, a High Performance Liquid Chromatography (HPLC) method was developed in this study.Methods: DNA was extracted from 30 primary breast tumors and 20 blood samples of healthy donors. ErbB1 and ErbB2 genes along with a reference gene were co-amplificated by Polymerase Chain Reaction (PCR). The PCR products were separated and quantified using an anion-exchange column within 30 min and in a single step. Optimum resolution was obtained when a sodium chloride gradient and a column temperature of 35oC were used. The results of HPLC analysis of ErbB1 and ErbB2 PCR products were compared with real time PCR method as a gold standard test for 7 tumor samples.Results: The proposed HPLC method was confirmed by real time PCR method.Twenty two and ten of the specimens in our breast cancer cohort showed more than a two-fold amplification of ErbB2 and ErbB1 oncogenes, respectively.Conclusion: Our results were confirmed by real time PCR and showed that HPLC method is a specific, cheap and clinically applicable analytical approach for assessment of ErbB1 and ErbB2 statuses in breast tumors.

Background: Application of adjuvants with microbial origins is a recently highlighted approach in the vaccinology trials. Archaeosomes are among these microbial compounds with both adjuvant and liposomal activities and features.Methods: In the present study, recombinant HBsAg encapsulated into Methanobrevibacter smithii (M. smithii) archaeosomes. Balb/c mice immunized with this compound and humoral and cytokine secretion pattern of immunized models analyzed.Results: Frequency of IFN-g secreting cells in the HBsAg-containing archaeosomes group was significantly higher than HBsAg and HBsAg+C/IFA groups (p≤0.05). IgG2a titer in the sera of HBsAg-containing archaeosomes group was also significantly higher than this subclass titer in the other groups (p≤0.05).Conclusion: Analysis of induced responses revealed the immunopotentiating characteristics of M. smithii archaeosomes in the induction of T-helper 1 responses according to the dominance of IgG2a subtype and IFN-g secreting splenocytes of immunized mice.

Background: Classification of molar gestation into Complete Hydatidiform Mole (CHM) and Partial Hydatidiform Mole (PHM) is done according to clinical, ultrasonographic, histologic and genetic criteria. However, making a distinction between CHM and PHM using histologic criteria alone may be difficult and several studies have shown that misclassifications are frequent, even for experienced pathologists. CHM is the most common precursor to choriocarcinoma and heterozygous moles carry an increased predisposition to transformation.Methods: Formalin-fixed, paraffin-embedded tissue sections of patients as well as peripheral blood of patients and their partners’ were collected in EDTA tubes. Tissue samples were obtained by curettage. Histological evaluation was performed on routine section stained with Hematoxylin and Eosin. Variable Number Tandem Repeats (VNTRs) genotyping was performed for 30 cases in two groups of CHM (n=21) and PHM (n=9), with Polymerase Chain Reaction (PCR) amplification of 2 different polymorphic loci, namely the Col2A1 and D1S80.Results: The results of DNA analysis by VNTR genotyping showed that in 16 cases of CHM, amplification of the VNTR polymorphic loci showed androgenetic mono-spermic moles (homozygote) and in 5 cases of CHM androgenetic dispermic moles (heterozygote) in molar tissue. In cases of PHM, 6 samples were triploid dispermic and 3 samples were diploid biparental.Conclusion: This study confirmed that VNTR genotyping can identify the parental source of polymorphic alleles in hydatidiform mole. Compared to STR genotyping, VNTR genotyping was performed by PCR amplification of several minisatellite markers of DNA. This method significantly requires less time and is cost-effective.