فهرست مطالب tahere seifi

Glioblastoma (GBM, known as Glioblastoma Multiforme) is one of the most common and also most aggressive solid tumors in adults. It has a poor prognosis and highly invasive behavior leading to difficulties in complete therapy. Understanding the fundamental glioblastoma biology and the molecular landscape beyond GBM metastasis is needed and highly crucial for better diagnosis and therapy. One of the major challenges reported for most cancer cells is the disruption of the glycosylation pattern of tumor cells, causing tumor progression, metastasis, and cancer resistance to chemotherapy and radiation therapy.

Platelet-derived growth factor (PDGF) and neuropilin-1 (NRP-1) play important roles in glioma progression; besides, the extracellular signal-regulated kinases (ERKs) and having mediated transducing growth factor signals to the nucleus, are of the most important regulatory factors governing various biological responses, including cell proliferation, differentiation, and motility. These factors are expressed in GBM. The growing evidence has documented different interactions between NRP-1 and PDGF-1 or PDGFR, causing cross-talk (directly or indirectly) between biochemical signaling and physical forces orchestrating cellular signaling, especially angiogenesis.

EC50 of sialic acid was determined using an MTT assay. After treatment for 24h, immunochemical detection of VEGF/VEGFR was performed using the immunocytochemistry for VEGF/VEGF-R1. Also, the immuno-blotting assay was applied for NRP-1 and PDGF-D detection.

In this study, we reported a strong correlation between PDGF-D, NRP-1 expression, and ERK1/2 signaling activations in 1321N1 glioma exposed to EC50 of sialic acid, which was verified using western-blot analysis. As a result, sialic acid as a mediator and transducer of the microenvironment-cell signaling might trigger cell motility through up-regulation of growth factors and chemoresistance. To sum up, control and normalization of sialic acid production in the cell microenvironment and niche could make the resistant GBM cell more sensitive to radiation therapy, chemotherapy, and immunotherapy.

Multiple sclerosis (MS) seems to be a multifactorial disease in which the environment and genetics are involved. One of the factors associated with MS disease is the reduction in vitamin D levels and its specialized role in its pathogenicity. In Iran, Khuzestan province has a high relative incidence of the Multiple sclerosis (MS) after the provinces of Isfahan and Markazi, The polymorphism rs10735810 in the VDR gene with change in the initial codon is one of the factors associated with other known diseases, including osteoporosis and diabetes.

In this study, the association of this variant in one hundred and fifty individuals with MS disease was compared with one hundred and fifty healthy individuals. PCR-sequencing was used to determine genotypes.

In the patient group, 16 cases had CC genotype, 59 had CT genotype and 75 had TT genotype, which did not show any significant difference in comparison with the control group (P>0.05). Also, there was no significant difference in the alleles distribution in the patient population compared to control (50% vs. 47.55% P=0.47). Additionally, no association was found between age and sex, and the ethnicity of patients (p> 0.05).

The polymorphism rs10735810 in the VDR gene showed no association to the etiology of MS.

Recently, we have shown that peroxisomal protein expression was induced upon retinoic acid treatment in mouse embryonic stem cells during the process of neurogenesis. Thus, characterization of the respective promoter could elucidate the molecular aspects of transcriptional regulation of this gene. Using the conventional software programs for promoter prediction, a putative promoter region was identified approximately 561 bp upstream of the peroxisomal protein coding sequence. In order to clone this region with a GC-content of 71.01%, a cocktail of ammonium sulfate buffer supplied with two additive components, betaine and dimethyl sulfoxide, and a high concentration of MgCl2 was used. The modulated polymerase chain reaction composition significantly improved the amplification of GC-rich DNA target sequences. Improved amplification of this region was due to reduction in the formation of secondary structures by the GC-rich region. Therefore, this polymerase chain reaction composition could be generally used to facilitate the amplification of other GC-rich DNA sequences as verified by amplification of different GC rich regions.