Regulation of SPDEF expression by DNA methylation in advanced prostate cancer.

Introduction: Prostate cancer (PCa) presents a significant health challenge in men, with a substantial number of deaths attributed to metastatic castration resistant PCa (mCRPC). Moreover, African American men experience disproportionately high mortality rates due to PCa. This study delves into the pivotal role of SPDEF, a prostate specific Ets transcription factor, and its regulation by DNA methylation in the context of PCa progression. Methods: We performed Epigenetic reprogramming using daily treatment with non-toxic dose of 5Aza-2-deoxycytidine (5Aza-dC) for two weeks to assess its impact on PDEF expression in prostate cancer cells. Next, we conducted functional studies on reprogrammed cells, including cell migration (wound-healing assay), invasion (Boyden-Chamber test), and proliferation (MTT assay) to comprehensively evaluate the consequences of altered PDEF expression. We used bisulfite sequencing (BSP) to examine DNA methylation at SPDEF promoter. Simultaneously, we utilized siRNA-mediated targeting of key DNMTs (DNMT1, DNMT3A, and DNMT3B) to elucidate their specific role in regulating PDEF. We measured mRNA and protein expressions using qRT-PCR and immune-blotting techniques, respectively. Results: In this report, we observed that: a) there is a gradual decrease in SPDEF expression with a concomitant increase in methylated CpG sites within the SPDEF gene during prostate cancer progression from lower to higher Gleason grade; b) Expression of DNMT's (DNMT1, 3a and 3b) is increased during prostate cancer progression, and there is an inverse correlation between SPDEF and DNMT expression; c) SPDEF levels are decreased in RC77/T, a line of PCa cells from African American origin similar to PC3 and DU145 cells (CRPC cells), as compared to LNCaP cells , a line of androgen dependent cells,; d) the 5' CpG island of SPDEF gene are hypermethylated in SPDEF-negative CRPC ( PC3, DU145 and RC77/T) cell lines but the same regions are hypomethylated in SPDEF-positive castrate sensitive (LNCaP) cell line ; (e) expression of SPDEF in PCa cells lacking SPDEF decreases cell migration and invasion, but has no significant effect on cell proliferation, and; (f) treatment with the demethylating agent, 5-aza-2'-deoxycytidine, or silencing of the DNMT's by siRNA, partially restores SPDEF expression in SPDEF-negative PCa cell lines, and decreases cell migration and invasion. Discussion: These results indicate hypermethylation is a prevalent mechanism for decreasing SPDEF expression during prostate cancer progression. The data demonstrate that loss of SPDEF expression in prostate cancer cells, a critical step in cellular plasticity, results from a potentially reversible process of aberrant DNA methylation. These studies suggest DMNT activity as a potential therapeutic vulnerability that can be exploited for limiting cellular plasticity, tumor progression, and therapy resistance in prostate cancer.

IFNG-AS1 and MAF4 long non-coding RNAs are upregulated in acute leukemia patients who underwent bone marrow transplantation.

PURPOSE OF THE STUDY: Acute graft versus host disease (aGVHD) is an immune-mediated reaction that results in impaired immune and body function after allogeneic hematopoietic stem cell transplantation (allo-HSCT). lncRNAs have been discovered as particular T cell regulators, and alloreactive T cells have been known as a critical factor in aGVHD. As a result, we investigated the importance of lnc-MAF4 and IFNG-AS1 expression levels in aGVHD patients versus non-aGVHD patients. MATERIAL AND METHODS: This research included 38 patients with hematological disorders who were undergoing primary allo-HSCT. Human identical siblings or unrelated donors were used to collect stem cell. Samples were taken within days 0, 7, 14, 28, and 52±8 after transplantation. The expression of lncRNA levels was measured using the QRT-PCR technique. And the data were analyzed using GraphPad Prism 6 RESULTS: Our data revealed that LncRNA MAF4 and INFG-AS1 expression levels in aGVHD were not significantly different compared to the non-GVHD group immediately after transplantation, nor at day 7 or 14. However, the aGVHD group showed an overt up-regulation of the two lncRNAs on samples taken at day 28 and 52±8 compared to non-GVHD patients. DISCUSSION: Since the intracellular pathway of these lncRNAs shows a direct relationship with the IFNγ cytokine production resulting in differentiation to TH1 cells and inhibition of differentiation to TH2 cells, they can be, therefore, considered as suitable molecular candidates for the prediction of aGVHD in patients receiving HSCT.

The oncogenic and tumor suppressive roles of RNA-binding proteins in human cancers.

Posttranscriptional regulation is a mechanism for the cells to control gene regulation at the RNA level. In this process, RNA-binding proteins (RBPs) play central roles and orchestrate the function of RNA molecules in multiple steps. Accumulating evidence has shown that the aberrant regulation of RBPs makes  contributions to the initiation and progression of tumorigenesis via numerous mechanisms such as genetic changes, epigenetic alterations, and noncoding RNA-mediated regulations. In this article, we review the effects caused by RBPs and their functional diversity in the malignant transformation of cancer cells that occurs through the involvement of these proteins in various stages of RNA regulation including alternative splicing, stability, polyadenylation, localization, and translation. Besides this, we review the various interactions between RBPs and other crucial posttranscriptional regulators such as microRNAs and long noncoding RNAs in the pathogenesis of cancer. Finally, we discuss the potential approaches for targeting RBPs in human cancers.

Understanding the role of integrins in breast cancer invasion, metastasis, angiogenesis, and drug resistance.

Integrins are cell adhesion receptors, which are typically transmembrane glycoproteins that connect to the extracellular matrix (ECM). The function of integrins regulated by biochemical events within the cells. Understanding the mechanisms of cell growth by integrins is important in elucidating their effects on tumor progression. One of the major events in integrin signaling is integrin binding to extracellular ligands. Another event is distant signaling that gathers chemical signals from outside of the cell and transmit the signals upon cell adhesion to the inside of the cell. In normal breast tissue, integrins function as checkpoints to monitor effects on cell proliferation, while in cancer tissue these functions altered. The combination of tumor microenvironment and its associated components determines the cell fate. Hypoxia can increase the expression of several integrins. The exosomal integrins promote the growth of metastatic cells. Expression of certain integrins is associated with increased metastasis and decreased prognosis in cancers. In addition, integrin-binding proteins promote invasion and metastasis in breast cancer. Targeting specific integrins and integrin-binding proteins may provide new therapeutic approaches for breast cancer therapies. This review will examine the current knowledge of integrins' role in breast cancer.

Platelet-Rich and Platelet-Poor Plasma Might Play Supportive Roles in Cancer Cell Culture: A Replacement for Fetal Bovine Serum?

BACKGROUND: Platelet-Rich (PRP) and Platelet-Poor plasma (PPP) are widely used in research and clinical platforms mainly due to their capacities to enhance cell growth. Although the short half-life (5 days) and the high price of platelet products pose challenges regarding their usage, they maintain the growth regulatory functions for weeks. Thus, we aimed to assess the supplementary values of these products in human CCRF- CEM cancer cells. Mechanistically, we also checked if the PRP/PPP treatment enhances YKL-40 expression as a known protein regulating cell growth. METHODS: The PRP/PPP was prepared from healthy donors using manual stepwise centrifugation and phase separation. The viability of the cells treated with gradient PRP/PPP concentrations (2, 5, 10, and 15%) was measured by the MTT assay. The YKL-40 mRNA and protein levels were assessed using qRT-PCR and western blotting. The data were compared to FBS-treated cells. RESULTS: Our findings revealed that the cells treated by PRP/PPP not only were morphologically comparable to those treated by FBS but also showed greater viability at the concentrations of 10 and 15%. Moreover, it was shown that PRP/PPP induce cell culture support, at least in part, via inducing YKL-40 expression at both mRNA and protein levels in a time- and dose-dependent manner. CONCLUSION: Collectively, by showing cell culture support comparable to FBS, the PRP/PPP might be used as good candidates to supplement the cancer cell culture and overcome concerns regarding the use of FBS as a non-human source in human cancer research.

Generation of Induced Pluripotent Cancer Cells from Glioblastoma Multiform Cell Lines.

Generation of induced pluripotent stem cells (iPSCs) has been described as a powerful method to dedifferentiate the specialized cells to pluripotency. However, obtaining cancer-specific iPS cells (iPCs) encounters several barriers. The generation of iPCs provides valuable experimental platforms to mimic oncogenesis and offers potentials regarding drug screening. To overcome the difficulties regarding the iPC generation, we aimed at optimizing the generation of iPCs from glioblastoma multiform (GBM) cell lines and at understanding the potential barriers ahead of this process. The T731, T653, and mouse embryonic fibroblast cells were transduced by using retroviral plasmids encoding Oct4, Sox2, and Klf4. The cells were cultured on a layer of feeder cells for 14 days in iPS media and the obtained colonies were then picked and expanded to be evaluated for pluripotency markers by alkaline phosphatase staining, qRT-PCR, and Western blotting. Our findings confirmed resistance in cancer cells to achieve the pluripotency markers. In addition to designing technical tricks to obviate the barriers ahead of iPC generation, we suggested the small molecule PD98059 to enhance the efficiency of iPC generation from GBM cell lines. The resulting iPCs can further be used as a platform to study the mechanism of cancer formation and as a tool for drug screening for the treatment of patients with GBM.

Imatinib independent aberrant methylation of NOV/CCN3 in chronic myelogenous leukemia patients: a mechanism upstream of BCR-ABL1 function?

BACKGROUND: The NOV gene product, CCN3, has been reported in a diverse range of tumors to serve as a negative growth regulator, while acting as a tumor suppressor in Chronic Myelogenous Leukemia (CML). However, the precise mechanism of its silencing in CML is poorly understood. In the current study, we aimed to query if the gene regulation of CCN3 is mediated by the promoter methylation in the patients with CML. In addition, to clarify whether the epigenetic silencing is affected by BCR-ABL1 inhibition, we assessed the methylation status in the patients at different time intervals following the tyrosine kinase inhibition using imatinib therapy, as the first-line treatment for this type of leukemia. METHODS: To address this issue, we applied bisulfite-sequencing technique as a high-resolution method to study the regulatory segment of the CCN3 gene. The results were analyzed in newly diagnosed CML patients as well as following imatinib therapy. We also evaluated the correlation of CCN3 promoter methylation with BCR-ABL1 levels. RESULTS: Our findings revealed that the methylation occurs frequently in the promoter region of CML patients showing a significant increase of the methylated percentage at the CpG sites compared to normal individuals. Interestingly, this hypermethylation was indicated to be independent of BCR-ABL1 titers in both groups, which might suggest a mechanism beyond the BCR-ABL1 function. CONCLUSION: Despite suggesting that the CCN3 hypermethylation acts as a molecular mechanism independent of BCR-ABL1 function in CML patients, this scenario requires further validation by complementary experiments. In the case of acting upstream of BCR-ABL1 signaling, the methylation marker can provide early detection and a novel platform for targeted epigenetic modifiers for efficient treatment in imatinib resistant patients.

Apoptotic effect of resveratrol on human T-ALL cell line CCRF-CEM is unlikely exerted through alteration of BAX and BCL2 promoter methylation.

One of the fundamental barriers leading to failure of leukemia therapy is the resistance against conventional chemotherapies, common modality used to cure leukemia. Having the potential to trigger apoptosis in various human leukemia cell lines, resveratrol is regarded as a robust agent in chemotherapy regimens. The current study was aimed to assess whether the apoptotic effect of resveratrol on T-cell acute lymphoblastic leukemia cell line, CCRF-CEM, is exerted through DNA methylation of BAX and BCL2 gene promoters. For this purpose, the CCRF-CEM cells were treated by resveratrol under standard cell culture. To analyze the promoter DNA methylation changes, we used methylation-specific polymerase chain reaction technique following the resveratrol treatment at different dosages and time intervals. Based on our previous study, the resveratrol treatment can trigger apoptosis in CCRF-CEM cell line via upregulation of apoptotic BAX gene and downregulation of antiapoptotic BCL2 gene. Despite these alterations in gene expression, the current study reveals no changes in DNA methylation patterns of subjected genes following the resveratrol treatment. Unchanged status of DNA methylation of BAX and BCL2 genes may suggest that resveratrol causes the gene expression changes through a distinct mechanism which requires further studies to be understood.

Regulatory effect of resveratrol and prednisolone on MDR1 gene expression in acute lymphoblastic leukemia cell line (CCRF-CEM): An epigenetic perspective.

Chemotherapy is the most common method to treat leukemia as well as other types of human cancers. However, drug resistance has remained as the main challenge against the efficacy of treatments. Furthermore, having various adverse effects, chemotherapy drugs are becoming replaced by natural modalities for cancer therapy. In this regard, herbal components such as resveratrol and prednisolone have been identified to sensitize the leukemic cells to programmed cell death through a set of complex processes. In this study, we have examined DNA methylation on the human multidrug resistance gene 1 (MDR1) as a well-known marker for cellular drug resistance. We evaluated the effect of resveratrol and prednisolone on DNA methylation patterns of MDR1 gene promoter in the CCRF-CEM cell line as a representative for acute lymphoblastic leukemia. The study was aimed to clarify whether the MDR1 gene expression is regulated via DNA promoter methylation as a potential underlying mechanism, following exposure to resveratrol and prednisolone. Our data revealed that despite a strong influence to down-regulate the MDR1 expression, Resveratrol and Prednisolone did not alter the methylation pattern, suggesting other regulatory mechanisms in controlling the MDR1 expression in CCRF-CEM cell line. Unchanged status of DNA methylation of MDR1 gene may suggest that Resveratrol and Prednisolone causes the gene expression changes through a distinct mechanism which requires further studies to be understood. A more detailed understanding of the mechanisms beyond the regulation of the genes involved in cancer formation will help to design novel therapeutic strategies to fight the human cancers.

Patterns of DNMT1 Promoter Methylation in Patients with Acute Lymphoblastic Leukemia.

Background: Acute lymphoblastic leukemia (ALL) is a clonal malignant disorder characterized by an uncontrolled proliferation of immature T or B lymphocytes. Extensive studies have shown that the epigenetic changes, especially modified DNA methylation patterns in the regulatory regions through the DNA methyltransferase (DNMTs), play an important role in the development of genetic disorders and abnormal growth and maturation capacity of leukemic stem cells (LSCs).The aim of this study was to evaluate the changes in DNMT1 promoter methylation and its expression pattern in patients with ALL. Materials and Methods: In this experimental study, methylation specific PCR (MSP) was used to assess the methylation status of DNMT1 promoter regions in samples collected from ALL patients (n=45) and healthy control subjects. According to this method, un-methylated cytosine nucleotides are converted to uracil by sodium bisulfite and the proliferation of methylated and un-methylated regions are performed using specific primers for target sequences. Results: None of the patients with B and T-ALL showed methylated promoter regions of the DNMT1 gene, while the methylation pattern of both pre-B ALL patients and the control group showed a relative promoter methylation. Conclusion: Analysis of promoter methylation patterns in various subgroups of ALL has revealed the importance of DNMT1 in the regulation of gene expression. Likewise, extensive data have also highlighted the methylation-based mechanisms exerted by DNAM1 as one of the main participants regulating gene expression in B-ALL and T-ALL patients. Investigation of the overall DNA methylation pattern offers significant improvements in the prediction of disease prognosis and treatment response.

Microchips and their Significance in Isolation of Circulating Tumor Cells and Monitoring of Cancers.

In micro-fluid systems, fluids are injected into extremely narrow polymer channels in small amounts such as micro-, nano-, or pico-liter scales. These channels themselves are embedded on tiny chips. Various specialized structures in the chips including pumps, valves, and channels allow the chips to accept different types of fluids to be entered the channel and along with flowing through the channels, exert their effects in the framework of different reactions. The chips are generally crystal, silicon, or elastomer in texture. These highly organized structures are equipped with discharging channels through which products as well as wastes of the reactions are secreted out. A particular advantage regarding the use of fluids in micro-scales over macro-scales lies in the fact that these fluids are much better processed in the chips when they applied as micro-scales. When the laboratory is miniaturized as a microchip and solutions are injected on a micro-scale, this combination makes a specialized construction referred to as "lab-on-chip". Taken together, micro-fluids are among the novel technologies which further than declining the costs; enhancing the test repeatability, sensitivity, accuracy, and speed; are emerged as widespread technology in laboratory diagnosis. They can be utilized for monitoring a wide spectrum of biological disorders including different types of cancers. When these microchips are used for cancer monitoring, circulatory tumor cells play a fundamental role.