scholarly journals Quantification of the Lamin A/C Transcript Variants in Cancer Cell Lines by Targeted Absolute Quantitative Proteomics and Correlation with mRNA Expression

2019 ◽  
Vol 20 (8) ◽  
pp. 1902 ◽  
Author(s):  
Wedad Al-Qahtani ◽  
Mai Abduljabbar ◽  
Entissar AlSuhaibani ◽  
Anas Abdel Rahman ◽  
Ahmad Aljada

Lamin A/C proteins have key roles in nuclear structural integrity and chromosomal stability. Lamin A/C cumulative protein expression of all variants is reported by semi-quantitative Western blotting. To date, there have not been specific antibodies for the individual Lamin A/C transcript variants. We developed a mass spectrometric approach for the quantification of Lamin A/C transcript variants. A signature peptide for each specific splice variant of Lamin A/C was selected. A LC–MS/MS assay based on the selected signature peptides and their labeled internal standards was established to measure the expression of Lamin A/C transcript variant concentrations. The method validation was carried out according to Food and Drug Administration (FDA) guidelines. The expression levels of the Lamin A/C transcript variants were measured in samples derived from MCF7 and U937 cell lines. RT-qPCR assay was also used to quantitate and compare the mRNA expression of splice variants of Lamin A/C. The established and validated method showed a great linearity, sensitivity, and precision. The different expressed Lamin A/C variants in different cell lines were measured and their levels were in concordance with qRT-PCR results. The developed method is reproducible, reliable, and sensitive for measuring different Lamin A/C transcript variants in different cell lines.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3634-3634
Author(s):  
Era L. Pogosova-Agadjanyan ◽  
Hana Lee ◽  
Crystal K. Cummings ◽  
Soheil Meshinchi ◽  
Jerald P. Radich ◽  
...  

Abstract Abstract 3634 Introduction: Interferon regulatory factor 8 (IRF8) is a transcription factor that plays a critical role in normal hematopoiesis. IRF8−/− transgenic mice develop a myeloproliferative syndrome that transforms to acute myeloid leukemia (AML). IRF8 expression varies dramatically in the blasts of AML patients. A number of biological processes, including epigenetic changes, mutations, or alternative splicing, may contribute to the variability of IRF8 expression in AML patients. We investigated the potential causes of the aberrant IRF8 expression in AML blasts. Wild-type transcript (IRF8-WT): The entire coding sequence of IRF8 was amplified using HiFi Taq polymerase and sequenced from 7 leukemic cell lines and 12 AML samples. We did not find any mutations associated with aberrant expression of IRF8. Splice Variants (IRF8-SVs): The initial studies examining IRF8 coding region suggested transcript deviation in the 5′ region. The GeneRacer kit was used to sequence 5′-capped mRNA. We identified 3 previously-undescribed transcript variants. In all 3 sequences, exon 1 was spliced out and replaced by nucleotides from the terminal end of intron 1 (Figure 1A). Some of the splice variants contained potential in-frame start codons. Expression of 5′ Splice Variants in Leukemic Cell Lines and AML Samples: We examined the expression levels of transcript variants in 12 leukemic cell lines, 246 AML samples, and hematopoietic subpopulations of cells from “healthy” adults. IRF8-SVs were expressed at significantly higher levels in some AML blasts than normal hematopoietic cells. In fact, AML cell lines with the highest IRF8 levels primarily expressed the IRF8-SVs rather than the IRF8-WT. Promoter Methylation: Interferon response element (pIRE) within the IRF8 promoter, which controls the expression of the gene, was examined by PCR after bisulfite conversion. Cell lines with very low IRF8 expression were often methylated at the pIRE locus. In addition, some cell lines with marked over-expression of IFR8-SVs also displayed methylated pIRE, suggesting that promoter methylation may also be playing a role in controlling the expression of the splice variants. pIRE methylation was also examined in a more limited number of AML samples, finding that blasts with low expression of IRF8 were methylated at this locus (Figure 1B). Reversal of Splice Variant Expression Pattern: Our previous studies suggested that methylation may play a role in controlling IRF8-SVs expression. Therefore, we examined the effect of demethylating agents on IRF8-SVs expression in U937 cells – a leukemic cell line with very high levels of IRF8-SVs. IRF8 transcripts (WT and SVs) were examined before and after exposure to therapeutic levels of 5-azacytidine (5-Aza). These studies suggested that 5-Aza exposure and subsequent demethylation of the pIRE locus was associated with restoration of the IRF8-WT and decreased IRF8-SVs expression (Figure 1C). This later data provides additional evidence that pIRE hypermethylation may regulate the expression of the novel IRF8-SVs. Conclusions: We have identified novel IRF8 transcript variants that are over-expressed in AML blasts. These novel IRF8-SVs introduce additional nucleotides at the 5′ region of the gene and may result in a new start codon. AML blasts with high levels of IRF8 transcript often over-express IRF8-SVs. Although the functional significance of these variants is unknown, methylation may play a role in regulating their expression, such that demethylating agents decrease IRF8-SVs and promote the IRF8-WT expression. Additional studies are planned to investigate the biology and clinical significance of IRF8-SVs. Initial studies suggests that over-expression of IRF8-SVs is associated with an inferior clinical outcome for adult AML patients. Disclosures: No relevant conflicts of interest to declare.


2018 ◽  
Vol 12 (02) ◽  
pp. 155-165
Author(s):  
Holger Hendrix ◽  
Vladimir Kamlak ◽  
Georgi Prisadov ◽  
Katrin Welcker

The treatment of pain after thoracic surgery is a challenge and takes place in the individual clinics mostly according to clinic internal standards. It exists no currently valid S3 guideline for the treatment of acute perioperative and posttraumatic pain. For an effective pain treatment as well individual pain experience as the pain intensity of the various thoracic surgical procedures must be considered. Regular pain assessment with appropriate methods and their documentation form the basis for adequate and adapted pain therapy.There are a number of different pain therapy methods, non-medicamentous and drug-based methods, whose effectiveness is described in the literature partially different. For the treatment of acute postoperative pain after thoracic surgery, mainly drug-related procedures are used, except for physiotherapy as a non-medicamentous method. Increasingly, alternative procedures for the peridural catheter as a therapeutic gold standard in the treatment of pain after thoracic surgery are used. Their application can be integrated into a therapeutic algorithm.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1820
Author(s):  
Chengcheng Hao ◽  
Yuxin Cui ◽  
Jane Lane ◽  
Shuqin Jia ◽  
Jiafu Ji ◽  
...  

Background: Osteopontin (OPN) splice variants are identified as predictors of tumour progression and therapeutic resistance in certain types of solid tumours. However, their roles in gastric cancer (GC) remain poorly characterized. The current study sought to assess the prognostic value of the three OPN splice variants (namely OPN-a, OPN-b, and OPN-c) in gastric cancer and their potential functions within gastric cancer cells. Methods: RNA extraction and reverse transcription were performed using our clinical cohort of gastric carcinomas and matched normal tissues (n = 324 matched pairs). Transcript levels were determined using real-time quantitative PCR. Three OPN splice variants overexpressed cell lines were created from the gastric cancer cell line HGC-27. Subsequently, biological functions, including cell growth, adhesion, migration, and invasion, were studied. The potential effects of OPN isoforms on cisplatin and 5-Fu were evaluated by detecting cellular reactive oxygen species (ROS) levels in the HGC-27-derived cell lines. Results: Compared with normal tissues, the expression levels of three splice variants were all elevated in gastric cancer tissues in an order of OPN-a > OPN-b > OPN-c. The OPN-a level significantly increased with increasing TNM staging and worse clinical outcome. There appeared to be a downregulation for OPN-c in increasing lymph node status (p < 0.05), increasing TNM staging, and poor differentiation. High levels of OPN-a and OPN-b were correlated with short overall survival and disease-free survival of gastric cancer patients. However, the low expression of OPN-c was significantly associated with a poor prognosis. Functional analyses further showed that ectopic expression of OPN-c suppressed in vitro proliferation, adhesiveness, migration, and invasion properties of HGC-27 cells, while the opposite role was seen for OPN-a. Cellular ROS detection indicated that OPN-a and OPN-c significantly promoted ROS production after treatment with 5-Fu comparing to OPN-vector, while only OPN-a markedly induced ROS production after treatment with cisplatin. Conclusion: Our results suggest that OPN splice variants have distinguished potential to predict the prognosis of gastric cancer. Three OPN variants exert distinctive functions in gastric cancer cells. Focusing on specific OPN isoforms could be a novel direction for developing diagnostic and therapeutic approaches in gastric cancer.


2021 ◽  
pp. 002436392110176
Author(s):  
Nicanor Pier Giorgio Austriaco

In recent months, there has been a lot of debate surrounding the use of those COVID-19 vaccines that have been either tested or manufactured with cell lines that were isolated from the remains of an aborted fetal child. Most faithful and orthodox Catholic moral theologians, among whom I count myself, have concluded that their use is not intrinsically evil. Therefore, like every other decision that falls into the category of actions that are not intrinsically evil, the decision to be vaccinated with these morally controversial vaccines has to be governed by the virtue of prudence. It is a decision that calls for a wisdom that properly sees this action within the constellation of actions that propels the human agent to the heights of holiness. This is why prayer is so essential for authentic moral judgment. With prayer, we ask the Holy Spirit who is the all-prudent one to guide our actions so that we can choose and act well not only for our only well-being but for the well-being of all. Acts that are not themselves intrinsically evil are deemed virtuous or not within the narrative of the individual person’s life.


2021 ◽  
Vol 9 (6) ◽  
pp. 1305
Author(s):  
Carlos Alonso Domínguez-Alemán ◽  
Luis Alberto Sánchez-Vargas ◽  
Karina Guadalupe Hernández-Flores ◽  
Andrea Isabel Torres-Zugaide ◽  
Arturo Reyes-Sandoval ◽  
...  

A common hallmark of dengue infections is the dysfunction of the vascular endothelium induced by different biological mechanisms. In this paper, we studied the role of recombinant NS1 proteins representing the four dengue serotypes, and their role in promoting the expression and release of endocan, which is a highly specific biomarker of endothelial cell activation. We evaluated mRNA expression and the levels of endocan protein in vitro following the stimulation of HUVEC and HMEC-1 cell lines with recombinant NS1 proteins. NS1 proteins increase endocan mRNA expression 48 h post-activation in both endothelial cell lines. Endocan mRNA expression levels were higher in HUVEC and HMEC-1 cells stimulated with NS1 proteins than in non-stimulated cells (p < 0.05). A two-fold to three-fold increase in endocan protein release was observed after the stimulation of HUVECs or HMEC-1 cells with NS1 proteins compared with that in non-stimulated cells (p < 0.05). The blockade of Toll-like receptor 4 (TLR-4) signaling on HMEC-1 cells with an antagonistic antibody prevented NS1-dependent endocan production. Dengue-infected patients showed elevated serum endocan levels (≥30 ng/mL) during early dengue infection. High endocan serum levels were associated with laboratory abnormalities, such as lymphopenia and thrombocytopenia, and are associated with the presence of NS1 in the serum.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bokyung Ahn ◽  
Yang Seok Chae ◽  
Soo Kyung Lee ◽  
Moa Kim ◽  
Hyeon Soo Kim ◽  
...  

AbstractAdenylate kinase 5 (AK5) belongs to the adenylate kinase family that catalyses reversible phosphate transfer between adenine nucleotides, and it is related to various energetic signalling mechanisms. However, the role of AK5 in colorectal cancer (CRC) has not been reported. In this study, AK5 was significantly hypermethylated in CRC compared to adjacent normal tissues (P < 0.0001) and normal tissues (P = 0.0015). Although the difference in mRNA expression was not statistically significant in all of them, the selected 49 cases of CRC tissues with AK5 hypermethylation with the cut off value of 40% showed a significant inverse correlation with mRNA expression (P = 0.0003). DNA methylation of AK5 promoter significantly decreased and AK5 expression recovered by 5-aza-2′-deoxycytidine, DNA methyltransferase inhibitor in CRC cell lines. In addition, AK5 promoter activity significantly decreased due to DNA methyltransferase, and it increased due to 5-aza. Moreover, AK5 regulated the phosphorylated AMPK and mTOR phosphorylation and inhibited the cell migration and cell invasion in CRC cell lines. Furthermore, low AK5 expression is associated with poor differentiation (P = 0.014). These results demonstrate that the AK5 promoter is frequently hypermethylated and induced methylation-mediated gene down-regulation. AK5 expression regulates AMPK/mTOR signalling and may be closely related to metastasis in colorectal adenocarcinoma.


1995 ◽  
Vol 64 (3) ◽  
pp. 182-188 ◽  
Author(s):  
Eveliene Manten-Horst ◽  
Erik H. J. Danen ◽  
Lia Smit ◽  
Margriet Snoek ◽  
I. Le Caroline Poole ◽  
...  

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