323 The Subcellular Expression Patterns of Bcl-Xl in Primary Brain Tumour Samples

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
A Vassiliou ◽  
K Alavian ◽  
M Tsujishita ◽  
H Bae

Abstract Introduction Primary brain tumours originate from cells within the brain. The commonest malignant types are gliomas which are graded from I-IV. Emerging evidence has elucidated the function of the mitochondrially localised B-cell lymphoma-extra-large (Bcl-xL) protein, and its promotion of tumour progression-associated properties. Our lab has previously established that Bcl-xL-overexpressing neurons increase metabolic efficiency by producing more adenosine triphosphate and consuming less oxygen, which we assumed, fuels cancer cells to proliferate. Method We quantified the subcellular expression patterns of Bcl-xL in primary brain tumour samples through immunohistochemistry on a brain tissue microarray containing 16 glioma cases from Grades II-IV. We used antibodies against Bcl-xL, heat shock protein 60 for mitochondrial detection and proliferating cell nuclear antigen for cancerous cell detection. Results Bcl-xL is overexpressed in cancerous cells of Grade IV gliomas and is significantly greater than cancerous cells of Grade III and Grade II gliomas. Cancerous cells express higher levels of Bcl-xL than non-cancerous cells in all grades of glioma. Conclusions Bcl-xL-overexpressing neurons exhibit enhanced metabolic efficiency, contributing to increased proliferation rates. Future research should focus on the characterisation of ATP levels and oxygen consumption in glioma cells. Conclusively, pharmacological inhibition of Bcl-xL will suppress the proliferation rate in gliomas and cease cancer cell growth.

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
A Vassiliou ◽  
K Alavian ◽  
M Tsujishita ◽  
H Bae

2011 ◽  
Vol 223 (06) ◽  
Author(s):  
J Bode ◽  
A Sabag ◽  
S Kietz ◽  
G Neufeld ◽  
M Lakomek

2021 ◽  
Vol 9 (6) ◽  
pp. e002558
Author(s):  
Richard S.P. Huang ◽  
Brennan Decker ◽  
Karthikeyan Murugesan ◽  
Matthew Hiemenz ◽  
Douglas A. Mata ◽  
...  

BackgroundThe effects of non-amplification short variant (SV) mutations in CD274 (programmed death-ligand 1 (PD-L1)) on PD-L1 protein expression and immune checkpoint inhibitors (ICPIs) therapy are unknown. Here, we present a retrospective analysis of CD274 mutations detected by comprehensive genomic profiling (CGP) and correlate these results with tumor-cell PD-L1 immunohistochemistry (IHC)-based expression assessment to better understand the relationship between mutations and protein expression of PD-L1.MethodsCGP was performed on hybridization-captured, adaptor ligation-based libraries using DNA and/or RNA extracted from 314,631 tumor samples that were sequenced for up to 406 cancer-related genes and select gene rearrangements. PD-L1 IHC was performed on a subset of cases (n=58,341) using the DAKO 22C3 PD-L1 IHC assay and scored with the tumor proportion score (TPS).ResultsOverall, the prevalence of CD274 SV mutations was low (0.3%, 1081/314,631) with 577 unique variants. The most common CD274 SV mutations were R260H (n=51), R260C (n=18), R125Q (n=12), C272fs*13 (n=11), R86W (n=10), and R113H (n=10). The prevalence of CD274 mutations varied depending on tumor type with diffuse large B-cell lymphoma (1.9%, 19/997), cutaneous squamous cell carcinoma (1.6%, 14/868), endometrial adenocarcinoma (1.0%, 36/3740), unknown primary melanoma (0.9%, 33/3679), and cutaneous melanoma (0.8%, 32/3874) having the highest frequency of mutations. Of the R260H cases concurrently tested with PD-L1 IHC, most (81.8%, 9/11) had no PD-L1 expression, which contrasts to the five E237K cases where most (80%, 4/5) had PD-L1 expression. In addition, we saw a significantly lower level of PD-L1 expression in samples with a clonal truncating variant (nonsense or frameshift indel) when compared with samples with a subclonal truncating variants (mean: TPS=1 vs TPS=38; p<0.001), and also in clonal versus subclonal missense mutations (mean: TPS=11 vs TPS=22, respectively; p=0.049)ConclusionsWe defined the landscape of CD274 mutations in a large cohort of tumor types that can be used as a reference for examining CD274 mutations as potential resistance biomarkers for ICPI. Furthermore, we presented novel data on the correlation of CD274 mutations and PD-L1 protein expression, providing important new information on the potential functionality of these mutations and can serve as a basis for future research.


2020 ◽  
Vol 22 (1) ◽  
pp. 141
Author(s):  
George Anderson

This article reviews the dynamic interactions of the tumour microenvironment, highlighting the roles of acetyl-CoA and melatonergic pathway regulation in determining the interactions between oxidative phosphorylation (OXPHOS) and glycolysis across the array of cells forming the tumour microenvironment. Many of the factors associated with tumour progression and immune resistance, such as yin yang (YY)1 and glycogen synthase kinase (GSK)3β, regulate acetyl-CoA and the melatonergic pathway, thereby having significant impacts on the dynamic interactions of the different types of cells present in the tumour microenvironment. The association of the aryl hydrocarbon receptor (AhR) with immune suppression in the tumour microenvironment may be mediated by the AhR-induced cytochrome P450 (CYP)1b1-driven ‘backward’ conversion of melatonin to its immediate precursor N-acetylserotonin (NAS). NAS within tumours and released from tumour microenvironment cells activates the brain-derived neurotrophic factor (BDNF) receptor, TrkB, thereby increasing the survival and proliferation of cancer stem-like cells. Acetyl-CoA is a crucial co-substrate for initiation of the melatonergic pathway, as well as co-ordinating the interactions of OXPHOS and glycolysis in all cells of the tumour microenvironment. This provides a model of the tumour microenvironment that emphasises the roles of acetyl-CoA and the melatonergic pathway in shaping the dynamic intercellular metabolic interactions of the various cells within the tumour microenvironment. The potentiation of YY1 and GSK3β by O-GlcNAcylation will drive changes in metabolism in tumours and tumour microenvironment cells in association with their regulation of the melatonergic pathway. The emphasis on metabolic interactions across cell types in the tumour microenvironment provides novel future research and treatment directions.


Genes ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1132
Author(s):  
Emel Rothzerg ◽  
Xuan Dung Ho ◽  
Jiake Xu ◽  
David Wood ◽  
Aare Märtson ◽  
...  

The human genome encodes thousands of natural antisense long noncoding RNAs (lncRNAs); they play the essential role in regulation of gene expression at multiple levels, including replication, transcription and translation. Dysregulation of antisense lncRNAs plays indispensable roles in numerous biological progress, such as tumour progression, metastasis and resistance to therapeutic agents. To date, there have been several studies analysing antisense lncRNAs expression profiles in cancer, but not enough to highlight the complexity of the disease. In this study, we investigated the expression patterns of antisense lncRNAs from osteosarcoma and healthy bone samples (24 tumour-16 bone samples) using RNA sequencing. We identified 15 antisense lncRNAs (RUSC1-AS1, TBX2-AS1, PTOV1-AS1, UBE2D3-AS1, ERCC8-AS1, ZMIZ1-AS1, RNF144A-AS1, RDH10-AS1, TRG-AS1, GSN-AS1, HMGA2-AS1, ZNF528-AS1, OTUD6B-AS1, COX10-AS1 and SLC16A1-AS1) that were upregulated in tumour samples compared to bone sample controls. Further, we performed real-time polymerase chain reaction (RT-qPCR) to validate the expressions of the antisense lncRNAs in 8 different osteosarcoma cell lines (SaOS-2, G-292, HOS, U2-OS, 143B, SJSA-1, MG-63, and MNNG/HOS) compared to hFOB (human osteoblast cell line). These differentially expressed IncRNAs can be considered biomarkers and potential therapeutic targets for osteosarcoma.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Godwin Adakole Ujah ◽  
Victor Udo Nna ◽  
Joseph Bagi Suleiman ◽  
Chinedum Eleazu ◽  
Chukwuemeka Nwokocha ◽  
...  

AbstractDoxorubicin (DOX) is a broad-spectrum chemotherapeutic drug used in the treatment of cancers. It acts by generating reactive oxygen species in target cells. The actions are, however, not limited to cancerous cells as it attacks healthy cells, killing them. This study investigated the benefits of the antioxidant, tert-butylhydroquinone (tBHQ), on testicular toxicity following DOX therapy. Twenty-four adult male albino rats were assigned randomly into four groups (n = 6), namely: normal control (NC), tBHQ, DOX and tBHQ + DOX groups. tBHQ (50 mg/kg body weight in 1% DMSO) was administered orally for 14 consecutive days, while a single DOX dose (7 mg/kg body weight) was administered intraperitoneally on Day 8. DOX decreased sperm count, motility and viability, and decreased the levels of steroidogenesis-related proteins, and reproductive hormones. Furthermore, DOX decreased the expression of antioxidant cytoprotective genes, and decreased the protein level of proliferating cell nuclear antigen in the testis. Conversely, DOX increased the expression of pro-inflammatory and pro-apoptotic genes in the testis. These negative effects were ameliorated following the intervention with tBHQ. Our results suggest that tBHQ protects the testis and preserves both steroidogenesis and spermatogenesis in DOX-treated rats through the suppression of oxidative stress, inflammation and apoptosis.


Nursing ◽  
2007 ◽  
Vol 37 (1) ◽  
pp. 36-42 ◽  
Author(s):  
RACHEL L. PALMIERI

Blood ◽  
2021 ◽  
Author(s):  
Miguel A Galindo-Campos ◽  
Nura Lutfi ◽  
Sarah Bonnin ◽  
Carlos Martínez ◽  
Talia Velasco-Hernandez ◽  
...  

Dysregulation of the c-Myc oncogene occurs in a wide variety of haematologic malignancies and its overexpression has been linked with aggressive tumour progression. Here, we show that Poly (ADP-ribose) polymerase (PARP)-1 and PARP-2 exert opposing influences on progression of c-Myc-driven B-cell lymphomas. PARP-1 and PARP-2 catalyse the synthesis and transfer of ADP-ribose units onto amino acid residues of acceptor proteins in response to DNA-strand breaks, playing a central role in the response to DNA damage. Accordingly, PARP inhibitors have emerged as promising new cancer therapeutics. However, the inhibitors currently available for clinical use are not able to discriminate between individual PARP proteins. We found that genetic deletion of PARP-2 prevents c-Myc-driven B-cell lymphomas, while PARP-1-deficiency accelerates lymphomagenesis in the Em-Myc mouse model of aggressive B-cell lymphoma. Loss of PARP-2 aggravates replication stress in pre-leukemic Em-Myc B cells resulting in accumulation of DNA damage and concomitant cell death that restricts the c-Myc-driven expansion of B cells, thereby providing protection against B-cell lymphoma. In contrast, PARP-1-deficiency induces a proinflammatory response, and an increase in regulatory T cells likely contributing to immune escape of B-cell lymphomas, resulting in an acceleration of lymphomagenesis. These findings pinpoint specific functions for PARP-1 and PARP-2 in c-Myc-driven lymphomagenesis with antagonistic consequences that may help inform the design of new PARP-centred therapeutic strategies with selective PARP-2 inhibition potentially representing a new therapeutic approach for the treatment of c-Myc-driven tumours.


Sign in / Sign up

Export Citation Format

Share Document