6 research outputs found
Vitamin D and Its Deficiency in Saudi Arabia
Vitamin D is a hot topic that has attracted attention over the past 10 years, especially since a large proportion of people suffer from this nutrient deficiency. Vitamin D deficiency is estimated to be about 1 billion people all over the world and 50% in Asia and the Middle East. Saudi Arabia has also demonstrated a high prevalence of vitamin D deficiency among healthy Saudi individuals. This chapter provides, in detail, a clear and understandable identification of vitamin D, its function, source, synthesis, metabolism, status, and deficiency. The chapter also focuses on studying vitamin D deficiency in Saudi Arabia based on PubMed’s initial research criteria
siRNA screening of the kinome identified Aurora A kinase as a therapeutic target gene in cervical cancer
HPV oncogenes disable a number of tumour suppressor pathways, including p53 and Rb, contributing to the transformed phenotype. Loss of these critical host cell functions may also provide an opportunity to selectively target the destruction of HPV-transformed cells. We have performed an siRNA screen using the kinome (779 genes) library to identify genes that when depleted are synthetically lethal with HPV transformation. The primary and validations screens have confirmed Aurora A kinase (AURKA) as a potential synthetic lethal target selective for HPV transformed cells. AURKA has been further investigated using the selective small molecule inhibitor MLN8237. We found that MLN8237 was significantly more potent towards the HPV transformed cells. The effect was not a consequence of targeting mitosis as two other mitotic inhibitors, PLK1 inhibitor (BI2536) and taxol, demonstrated no selectivity. Analysis of the nuclear structure and DNA content showed that Aurora A inhibition promoted a high level of polyploidy in non-HPV treated cells whilst this same degree of polyploidy was associate with apoptosis in the HPV-transformed cell lines. Whereas Bcl-2 over expression in HeLa cells had no effect on sensitivity to MLN8237, Mcl-1 overexpressing HeLa cells were less sensitive to the MLN8237 in comparison to the parental cell line, which may suggests the involvement of Noxa or Puma pro-apoptotic proteins in the induction of the apoptosis in the HPV-transformed cells. The transfection of the non-HPV C33A cervical cancer and SCC25 squamous cell carcinoma cell lines with the HPV16 oncogenic E7 increased sensitivity to MLN8237 between 3 >10 fold suggesting that the sensitivity to MLN8237-dependent killing was a direct consequence of HPV E7 expression. Xenograft experiments with cervical cancer cell lines in immunodeficient mice showed MLN8237 inhibited growth of HPV and non-HPV xenografts during treatment with 30mg/kg MLN8237 once a day for 10 consecutive days. However, outgrowth of tumour was noticed from the second day post-treatment in the non-HPV tumour group whereas the HPV-induced tumour group did not show cancer recurrence for 50 days post-treatment. These findings suggest that MLN8237 represent a promising novel therapeutic targeted agent against HPV-transformed cervical cancer
Stability and validity of intact parathyroid hormone levels in different sample types and storage conditions
Background
Several pre-analytical factors can affect the measurement of intact Parathyroid Hormone (IPTH). In this study, we have investigated the effects of using different types of tubes, time elapsed before separation, and storage conditions over time on the measured values of IPTH.
Method
Blood samples from 30 subjects were collected into plain, SST, and EDTA tubes. All serum and plasma were separated immediately (first set) and after 2 hrs delay (second set). The first set of samples were aliquoted and stored at RT (25°C), at fridge (4°C), and freezer (−20°C). IPTH was measured in all the stored aliquots at 2,4, and 8 days after collection using Architect analyzer.
Results
Paired T test and ANOVA repeated measures showed no significant difference between IPTH levels in all tubes. The second set of serum and plasma were significantly lower (3.8% and 7.4%, p < 0.001, respectively) when compared to samples measured initially. Serum samples stored at RT were significantly lower (by 45%,59%, and 77%) on days 2,4, and 8 when compared to the initial time (p < 0.001 in all cases). Plasma samples stored at RT, were significantly lower on day 8 after collection, by 30.8% (p < 0.001). These differences would be clinically important.
Conclusion
Plasma IPTH can be stored at RT for up to four days. Both plasma and serum IPTH are not affected by a delay in the separation of up to two h and they can be stored for up to 8 days in a fridge or freezer without any clinically significant changes in their values
Design and Implementation of High Throughput Screening Assays for Drug Discoveries
The process of drug discovery is challenging and a costly affair. It takes about 12 to 15Â years and costs over $1 billion dollars to develop a new drug and introduce the finished product in the market. With the increase in diseases, virus spread, and patients, it has become essential to invent new medicines. Consequently, today researchers are becoming interested in inventing new medicines faster by adopting higher throughput screening methods. One avenue of approach to discovering drugs faster is the High-Throughput Screening (HTS) method, which has gained a lot of attention in the previous few years. Today, High-Throughput Screening (HTS) has become a standard method for discovering drugs in various pharmaceutical industries. This review focuses on the advancement of technologies in High-Throughput Screening (HTS) methods, namely fluorescence resonance energy transfer (FRET), biochemical assay, fluorescence polarization (FP), homogeneous time resolved fluorescence (HTRF), Fluorescence correlation spectroscopy (FCS), Fluorescence intensity distribution analysis (FIDA), Nuclear magnetic resonance (NMR), and research advances in three major technology areas including miniaturization, automation and robotics, and artificial intelligence, which promises to help speed up the discovery of medicines and its development process
I libri greci di Teodoro Chrysoberges e i suoi passaggi a Costantinopoli (aprile 1415) e a Corfù (luglio 1419)
Free to read Human papillomavirus (HPV) is the causative agent in cervical cancer. HPV oncogenes are major drivers of the transformed phenotype, and the cancers remain addicted to these oncogenes. A screen of the human kinome has identified inhibition of Aurora kinase A (AURKA) as being synthetically lethal on the background of HPV E7 expression. The investigational AURKA inhibitor MLN8237/Alisertib selectively promoted apoptosis in the HPV cancers. The apoptosis was driven by an extended mitotic delay in the Alisertib-treated HPV E7–expressing cells. This had the effect of reducing Mcl-1 levels, which is destabilized in mitosis, and increasing BIM levels, normally destabilized by Aurora A in mitosis. Overexpression of Mcl-1 reduced sensitivity to the drug. The level of HPV E7 expression influenced the extent of Alisertib-induced mitotic delay and Mcl-1 reduction. Xenograft experiments with three cervical cancer cell lines showed Alisertib inhibited growth of HPV and non-HPV xenografts during treatment. Growth of non-HPV tumors was delayed, but in two separate HPV cancer cell lines, regression with no resumption of growth was detected, even at 50 days after treatment. A transgenic model of premalignant disease driven solely by HPV E7 also demonstrated sensitivity to drug treatment. Here, we show for the first time that targeting of the Aurora A kinase in mice using drugs such as Alisertib results in a curative sterilizing therapy that may be useful in treating HPV-driven cancers. Mol Cancer Ther; 14(12); 2753–61. ©2015 AACR