Acute aflatoxin B1 - Induced hepatotoxicity alters gene expression and disrupts lipid and lipoprotein metabolism in rats

In this study, alterations in lipid metabolism associated with acute aflatoxin B1 (AFB1) induced hepatotoxicity and gene expression changes underlying these effects were investigated. Rats were orally administered three doses (0.25 mg/kg, 0.5 mg/kg and 1.0 mg/kg) of AFB1 for seven days; after which blood was collected and liver excised. Lipid profiles of plasma and liver were determined spectrophotometrically while the expression of genes associated with lipid and lipoprotein metabolism was assayed by reverse transcriptase polymerase chain reaction. Acute exposure to AFB1 increased the levels of plasma and liver cholesterol, triglycerides and phospholipids. AFB1 at 0.5 mg/kg and 1.0 mg/kg resulted in a dose-dependent (1.2 and 1.5 fold, respectively) downregulation of hepatic Cpt1a with a concomitant 1.2 and 1.5 fold increase in the level of plasma FFA, respectively. A similar observation of 1.2 and 1.3 fold increase was also observed in plasma triglyceride concentration, at both respective doses. AFB1 also decreased the relative expression of Ahr, Lipc and Lcat whereas, it upregulated Scarb1 in a dose dependent manner. AFB1-induced dysregulation of the expression of lipid and lipoprotein metabolizing genes may be one mechanism linking AFB1 to altered lipid metabolism and ultimately risk for coronary heart disease.

Erythrocyte acetylcholinesterase activity as a surrogate indicator of lead-induced neurotoxicity in occupational lead exposure in Abeokuta, Nigeria

Dose-effect and dose-response relationships in occupational neurotoxicology are rarely studied by means of biochemical methods. In order to investigate the potential neurotoxic effects of lead during occupational exposure to this metal, the activity of erythrocyte acetylcholinesterase (AcChE), as well as blood pressure and pulse, were determined in various artisans in Abeokuta, Nigeria, who have been shown to be occupationally exposed to lead, and these were related to blood lead levels. AcChE activity in the artisans was inhibited to varying extents. While AcChE activity was inhibited to the tune of 39% in the male petrol station attendants, the inhibition amounted to 32% in female petrol station attendants. In other artisans, AcChE inhibition ranged from 31% in the welders to 38% in painters. The lowest inhibition of 15% was obtained in the panel beaters. Correlations, as calculated by Pearson's method, revealed a significant (p<0.001) inverse linear relationship between AcChE activity and blood lead levels (r=-0.40; y=-120.38x+13935.59; p<0.001). Blood pressure and pulse were not significantly different between control and lead-exposed subjects. Our findings suggest that erythrocyte AcChE activity could be used as a biomarker of lead-induced neurotoxicity in occupationally exposed subjects.

Naringin enhances reverse cholesterol transport in high fat/low streptozocin induced diabetic rats

Naringin, a citrus-derived flavonoid with antihyperglycemic, antihyperlipidemic, and antioxidant properties, is reported to be a useful nutraceutical in the management of diabetes and its complications. This study investigated the mechanism of antiatherogenic properties of naringin in type 2 diabetes (T2DM) using high fat-low streptozocin rat model of T2DM. Rats were treated daily with 50, 100 and 200 mg/kg naringin orally for 21days. Levels of biomarkers of T2DM, lipid profile and activity of paraoxonase (PON) were assayed spectrophotometrically. The levels of expression of hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase (Hmgcr), scavenger receptor class B member 1 (Scarb1), aryl hydrocarbon receptor (Ahr), hepatic Lipase (Lipc), and lecithin-cholesterol acyltransferase (Lcat) were assessed using relative reverse transcriptase polymerase chain reaction technique. Naringin treatment resulted in a dose-dependent significant (p < 0.05) decrease in the levels of plasma cholesterol and triglyceride from 84.84 ± 1.62 to 55.59 ± 1.50 mg/dL and 123.03 ± 15.11 to 55.00 ± 0.86 mg/dL, respectively, at 200 mg/kg naringin. In the liver, Scarb1 and Ahr were significantly (p < 0.05) upregulated at 200 mg/kg naringin while Lipc and Lcat were significantly (p < 0.05) upregulated by 50 mg/kg naringin. T2DM-induced decrease in PON activities in the plasma, liver and HDL was significantly (p < 0.05) reversed by 200 mg/kg naringin treatment. These genes play critical roles in reverse cholesterol transport and hence our results showed that the antiatherogenic property of naringin in T2DM involves enhancement of reverse cholesterol transport and PON activity.

Voltage Gated Sodium Channel Genes in Epilepsy: Mutations, Functional Studies, and Treatment Dimensions

Genetic epilepsy occurs as a result of mutations in either a single gene or an interplay of different genes. These mutations have been detected in ion channel and non-ion channel genes. A noteworthy class of ion channel genes are the voltage gated sodium channels (VGSCs) that play key roles in the depolarization phase of action potentials in neurons. Of huge significance are SCN1A, SCN1B, SCN2A, SCN3A, and SCN8A genes that are highly expressed in the brain. Genomic studies have revealed inherited and de novo mutations in sodium channels that are linked to different forms of epilepsies. Due to the high frequency of sodium channel mutations in epilepsy, this review discusses the pathogenic mutations in the sodium channel genes that lead to epilepsy. In addition, it explores the functional studies on some known mutations and the clinical significance of VGSC mutations in the medical management of epilepsy. The understanding of these channel mutations may serve as a strong guide in making effective treatment decisions in patient management.

Epigenetic modifications associated with in utero exposure to endocrine disrupting chemicals BPA, DDT and Pb

Endocrine disrupting chemicals (EDCs) are xenobiotics which adversely modify the hormone system. The endocrine system is most vulnerable to assaults by endocrine disruptors during the prenatal and early development window, and effects may persist into adulthood and across generations. The prenatal stage is a period of vulnerability to environmental chemicals because the epigenome is usually reprogrammed during this period. Bisphenol A (BPA), lead (Pb), and dichlorodiphenyltrichloroethane (DDT) were chosen for critical review because they have become serious public health concerns globally, especially in Africa where they are widely used without any regulation. In this review, we introduce EDCs and describe the various modes of action of EDCs and the importance of the prenatal and developmental windows to EDC exposure. We give a brief overview of epigenetics and describe the various epigenetic mechanisms: DNA methylation, histone modifications and non-coding RNAs, and how each of them affects gene expression. We then summarize findings from previous studies on the effects of prenatal exposure to the endocrine disruptors BPA, Pb and DDT on each of the previously described epigenetic mechanisms. We also discuss how the epigenetic alterations caused by these EDCs may be related to disease processes.

Preadministration of Fermented Sorghum Diet Provides Protection against Hyperglycemia-Induced Oxidative Stress and Suppressed Glucose Utilization in Alloxan-Induced Diabetic Rats

Sorghum bicolor grains are rich in phytochemicals known to considerably impact human health. Several health-promoting products such as flour, staple food, and beverages have been produced from sorghum grains. This study investigated the protective and modulatory effects of a sorghum diet on the genes of some antioxidant and glycolytic enzymes in alloxan-induced diabetic rats. The rats were randomly distributed into six groups: the control group received normal diet, while the other groups were pretreated with 12.5, 25, 50, 75, and 100% of the sorghum diets daily for 8 weeks before the administration of a dose of alloxan (100 mg/kg BW), after which blood was collected and the liver was excised. The effects of the diets on blood glucose levels, liver dysfunction indices, and markers of oxidative stress were assessed spectrophotometrically, while the gene expressions of key glycolytic enzymes and enzymatic antioxidants were assayed using reverse transcriptase polymerase chain reaction. It was observed that the pretreatment of the experimental animals with the diets normalized the blood glucose before and after the administration of alloxan. The sorghum-treated groups also showed statistically significant (p < 0.05) decrease in liver dysfunction indices and markers of oxidative damage compared with the control. In addition, statistically the diets significantly decreased (p < 0.05) the relative expression of superoxide dismutase, glutathione peroxidase, glucokinase, phosphofructokinase, and hexokinase genes in the experimental animals compared with the control. Overall, this study showed that the preadministration of fermented sorghum diet significantly protected against hyperglycemia and suppressed glucose utilization via glycolysis in the liver of alloxan-induced diabetic rats. Thus, the consumption of sorghum diet may protect against hyperglycemia and oxidative damage and may therefore serve as functional food for management of diabetic mellitus.

Hesperidin prevents lipopolysaccharide-induced endotoxicity in rats

CONTEXT

Lipopolysaccharide (LPS) is a major trigger of septic shock resulting in multiple organ damage through excessive stimulation of the host's immune cells resulting in the release of cytokines. Previous studies have shown that hesperidin has several beneficial properties against inflammation and oxidative stress.

OBJECTIVE

The influence of hesperidin on endotoxemia, endothelial dysfunction, inflammation, and oxidative stress was investigated using a murine model of sepsis.

MATERIALS AND METHODS

Rats were pretreated for 15 d with three doses (50 mg/kg, 100 mg/kg, and 200 mg/kg) of hesperidin prior to LPS administration. Afterwards, the levels of biomarkers of endotoxemia, endothelial dysfunction, and oxidative stress were assessed. Reverse transcriptase PCR technique was used to assess the expression of hepatic proinflammatory cytokines.

RESULTS

Hesperidin pretreatment significantly (p < 0.05) reduced circulating endotoxin, as well as the levels of bactericidal permeability increasing protein and procalcitonin, and the associated endothelial dysfunction by reducing the levels of plasma soluble intercellular adhesion molecules 1 and inducible nitric oxide (iNO) synthase. There was also down-regulation of the expression of gene for interleukin 1α, interleukin 1β, interleukin 1 receptor, interleukin 6, and tumor necrosis factor α (TNFα) in the liver of rats treated with LPS as a result of hesperidin pretreatment. Hesperidin also showed anti-oxidative properties through the significant (p < 0.05) reduction of NO, hydroperoxides, and thiobarbituric acid reactive substances and increase of glutathione, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase in the organs.

CONCLUSION

Different doses of hesperidin can prevent endotoxemia-induced oxidative stress as well as inflammatory and endothelial perturbation in rats when administered for as few as 15 d before exposure to endotoxin.

Stevioside modulates oxidative damage in the liver and kidney of high fat/low streptozocin diabetic rats

This study investigated the potential of stevioside to prevent oxidative DNA damage in the liver and kidney of type 2 diabetes mellitus (T2DM) using high fat-low streptozocin rat model. Rats were treated daily with 12.5, 25 and 50 mg/kg stevioside orally for 21 days. Levels of biomarkers of T2DM, lipid profile and oxidative stress were assayed spectrophotometrically. The DNA ladder assay method was used to assess DNA fragmentation in the liver and kidney while computational analysis was used to predict the mechanisms of antidiabetic properties of stevioside. Stevioside significantly (p < 0.05) decreased the levels of plasma glucose, insulin, dipeptidyl peptidase IV and activities of kidney angiotensin converting enzyme. Stevioside significantly reduced oxidative stress by decreasing the levels of lipid peroxidation and nitric oxide in the liver and kidney; thereby, reducing the extent of DNA fragmentation in the liver and kidney of the diabetic rats. The in silico analysis showed that the ability of stevioside to exert these effects is linked to its inhibition of beta-adrenergic receptor kinase and G-protein-coupled receptor kinase. The results of this study suggest that the prevention of DNA fragmentation may be an additional benefit of the use of stevioside in the management of T2DM.

Vitamin K protects against 7,12-dimethylbenz(A)anthracene induced hepatotoxicity in Wistar rats

Humans are daily exposed to 7,12-dimethylbenz(a)anthracene (DMBA), a well known polycyclic aromatic hydrocarbons (PAH). This study investigated the role of dietary intake of Vitamin K (VK), a polyphenolic compound, with potential antioxidative properties, against DMBA-induced hepatotoxicity. Sixty experimental animals (120-150 g) were divided into six groups (A-F): Control, DMBA (80 mg/kg bw) only, VK (0.00 g/10 kg) diet only, VK (7.5 g/10 kg) diet only, DMBA + VK (0.0 g/10 kg) diet and DMBA + VK (7.5 g/10 kg) diet. Single oral administration of DMBA (80 mg/kg body weight) to Wistar rats resulted in hepatic damage after 16 weeks. DMBA significantly (P < .05) decreased the activities of catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST) and glutathione peroxidase (GPx). Levels of reduced glutathione (GSH) and Vitamin C were significantly decreased with increase in malondialdehyde (MDA) and nitric oxide (NO) levels in serum and liver. Aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), γ-glutamyltransferase (GGT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) activities were significantly (P < .05) elevated in the serum but reduced in the liver of DMBA-administered group. Ingestion of 7.5 g/10 kg VK diet prevented the up regulations in inflammatory biomarkers (granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin 17A (IL-17A)) which elicited liver damaged in the DMBA-treated group. DMBA induced hepatic alterations in DMBA-treated group but was restored to near normal in VK (7.5 g/10 kg) diet group. These findings suggest the protective potential of increased dietary intake of vitamin K against DMBA-induced hepatic dysfunction.

Computational Identification of Metabolic Pathways of Plasmodium falciparum using the k-Shortest Path Algorithm

Plasmodium falciparum, a malaria pathogen, has shown substantial resistance to treatment coupled with poor response to some vaccines thereby requiring urgent, holistic, and broad approach to prevent this endemic disease. Understanding the biology of the malaria parasite has been identified as a vital approach to overcome the threat of malaria. This study is aimed at identifying essential proteins unique to malaria parasites using a reconstructed iPfa genome-scale metabolic model (GEM) of the 3D7 strain of Plasmodium falciparum by filling gaps in the model with nineteen (19) metabolites and twenty-three (23) reactions obtained from the MetaCyc database. Twenty (20) currency metabolites were removed from the network because they have been identified to produce shortcuts that are biologically infeasible. The resulting modified iPfa GEM was a model using the k-shortest path algorithm to identify possible alternative metabolic pathways in glycolysis and pentose phosphate pathways of Plasmodium falciparum. Heuristic function was introduced for the optimal performance of the algorithm. To validate the prediction, the essentiality of the reactions in the reconstructed network was evaluated using betweenness centrality measure, which was applied to every reaction within the pathways considered in this study. Thirty-two (32) essential reactions were predicted among which our method validated fourteen (14) enzymes already predicted in the literature. The enzymatic proteins that catalyze these essential reactions were checked for homology with the host genome, and two (2) showed insignificant similarity, making them possible drug targets. In conclusion, the application of the intelligent search technique to the metabolic network of P. falciparum predicts potential biologically relevant alternative pathways using graph theory-based approach.

Computer-Aided Analysis of Multiple SARS-CoV-2 Therapeutic Targets: Identification of Potent Molecules from African Medicinal Plants

The COVID-19 pandemic, which started in Wuhan, China, has spread rapidly over the world with no known antiviral therapy or vaccine. Interestingly, traditional Chinese medicine helped in flattening the pandemic curve in China. In this study, molecules from African medicinal plants were analysed as potential candidates against multiple SARS-CoV-2 therapeutic targets. Sixty-five molecules from the ZINC database subset (AfroDb Natural Products) were virtually screened with some reported repurposed therapeutics against six SARS-CoV-2 and two human targets. Molecular docking, druglikeness, absorption, distribution, metabolism, excretion, and toxicity (ADMET) of the best hits were further simulated. Of the 65 compounds, only three, namely, 3-galloylcatechin, proanthocyanidin B1, and luteolin 7-galactoside found in almond (Terminalia catappa), grape (Vitis vinifera), and common verbena (Verbena officinalis), were able to bind to all eight targets better than the reported repurposed drugs. The findings suggest these molecules may play a role as therapeutic leads in tackling this pandemic due to their multitarget activity.

Modeling of the Glycolysis Pathway in Plasmodium falciparum using Petri Nets

Malaria is one of the deadly diseases, which affects a large number of the world's population. The Plasmodium falciparum parasite during erythrocyte stages produces its energy mainly through anaerobic glycolysis, with pyruvate being converted into lactate. The glycolysis metabolism in P. falci-parum is one of the important metabolic pathways of the parasite because the parasite is entirely dependent on it for energy. Also, several glycolytic enzymes have been proposed as drug targets. Petri nets (PNs) have been recognized as one of the important models for representing biological pathways. In this work, we built a qualitative PN model for the glycolysis pathway in P. falciparum and analyzed the model for its structural and quantitative properties using PN theory. From PlasmoCyc files, a total of 11 reactions were extracted; 6 of these were reversible and 5 were irreversible. These reactions were catalyzed by a total number of 13 enzymes. We extracted some of the essential reactions in the pathway using PN model, which are the possible drug targets without which the pathway cannot function. This model also helps to improve the understanding of the biological processes within this pathway.

Gene Expression Profiling Analysis Reveals Putative Phytochemotherapeutic Target for Castration-Resistant Prostate Cancer

Prostate cancer is the leading cause of cancer death among men globally, with castration development resistant contributing significantly to treatment failure and death. By analyzing the differentially expressed genes between castration-induced regression nadir and castration-resistant regrowth of the prostate, we identified soluble guanylate cyclase 1 subunit alpha as biologically significant to driving castration-resistant prostate cancer. A virtual screening of the modeled protein against 242 experimentally-validated anti-prostate cancer phytochemicals revealed potential drug inhibitors. Although, the identified four non-synonymous somatic point mutations of the human soluble guanylate cyclase 1 gene could alter its form and ligand binding ability, our analysis identified compounds that could effectively inhibit the mutants together with wild-type. Of the identified phytochemicals, (8′R)-neochrome and (8′S)-neochrome derived from the Spinach (Spinacia oleracea) showed the highest binding energies against the wild and mutant proteins. Our results identified the neochromes and other phytochemicals as leads in pharmacotherapy and as nutraceuticals in management and prevention of castration-resistance prostate cancers.

Radiations and biodegradation techniques for detoxifying Carica papaya seed oil for effective dietary and industrial use

Benzyl isothiocyanate (BITC) is toxic in high concentration. The capacity of Aspergillus niger, microwave and ultraviolet radiations to reduce the BITC levels in Carica papaya Linn seed oil were assessed in vitro. BITC at different concentrations were periodically exposed to microwave and ultraviolet radiations for 30 min and 10 h, respectively; and to identify Aspergillus niger for 4 days. Microwave radiation significantly reduced (p < 0.05) BITC levels (0.0272, 0.0544, and 0.0816 μmol) to 12.19, 8.99 and 27.5 % respectively within 15 min. Ultraviolet radiation significantly reduced (p < 0.05) BITC levels at all the concentrations. A. niger significantly increased (p < 0.05) BITC degradation on days 2 and 4 at 0.816, 1.36 and 2.72 nmol. Glutathione activity was significantly increased (p < 0.05) while glutathione S-transferase activity significantly reduced (p < 0.05) at all concentrations on days 3 and 4 respectively. The three techniques are possible models for improving the dietary consumption of the oil.

Oral administration of marijuana produces alterations in serotonin 5-hydroxytryptamine receptor 3A gene (HTR3A) and electrolyte imbalances in brain of male Wistar rats

The gene expression of serotonin 5-hydroxytryptamine receptor 3A (receptor 3A:HTR3A) as well as the concentration of electrolytes in male Wistar rats after administration of graded doses of marijuana extract was investigated. Twelve groups (3 control and 9 test groups) of 6 animals each were daily exposed to 12.5, 25 and 50 mg/kg b.w doses of petroleum ether extract of marijuana for 4, 8 and 12 weeks. The expressions of the gene were obtained using reverse transcriptase-polymerase chain reaction (RT-PCR) while electrolytes concentrations were determined. An upregulation of over 90% was observed in the expression of HTR3A after exposure to the highest dose throughout the exposure period. There was significant increase in the plasma potassium concentration at all doses while there was a decrease in the brain only at 50 mg/kg dose throughout the exposure period. Sodium concentration in the brain was not affected by the doses over the period of exposure but plasma concentration decreased significantly. All the doses of marijuana extract significantly increased calcium concentration in the brain after prolonged exposure but the plasma concentration remained unchanged. This suggests that different doses of marijuana extract alter the expression of serotonin receptor and electrolyte concentrations over a period of time with possible neurological consequences.

Administration of Cannabis causes alterations in monoamine oxidase B and serotonin receptor 2C gene expressions in Wistar rats

This study examined the probable effects of graded doses of Cannabis sativa (C. sativa) extract on the gene expressions of monoamine oxidase B and serotonin receptor 2C (HTR2C) in an attempt to correlate the duration of use with neurodegeneration tendencies in chronic marijuana users. Male Wistar rats weighing between 90 g ± 100 g were treated with graded doses of petroleum ether extract of C. sativa (12.5, 25 and 50 mg/kg body weight) orally. The exposure was monitored at 4, 8, and 12 weeks for each of the doses employed, after which the brain was removed. The gene expressions were determined by reverse transcriptase polymerase chain reaction. Cannabis considerably (p < 0.05) reduced the relative expression of MAOB at 4 weeks. At 8 weeks, cannabis upregulated the relative expression of the MAOB gene by 60%. Following 12 weeks of exposure to the 50mg/kg body weight dose of C. sativa, 80% increase in the expression of MAOB was observed compared to the control group. C. sativa (50 mg/kg body weight) extract at 8 weeks resulted in about 47.7% decrease in the expression of the gene, however, prolonged exposure (12 weeks) to the extract significantly (p < 0.05) increased the relative expression of HTR2C. Cannabis-induced dysregulation of the MAOB genes may be one mechanism linking chronic use of cannabis to cognitive decline and improved likelihood of developing neurological diseases. Alterations observed in HTR2C gene expression as a result of exposure to high doses of C. sativa extract may partly account for the depression and aggressive tendencies observed in chronic users.

Abstract A087: Spatial RNA-seq reveals intratumor heterogeneity and transcriptional substructure in a diverse cohort of high-grade ovarian cancers

Introduction: Differences in tumor heterogeneity, particularly the tumor microenvironment have not yet been explored as potential molecular features underlying cancer disparities. Molecular profiling of bulk tissue specimens using methods such as whole-transcriptome sequencing are limited in their ability to resolve fine grain molecular signatures and hinder our utility to dissect underlying biology of individual tumors. Although informatics approaches are available that attempt to disentangle tissue heterogeneity from bulk tumor data, emerging spatial whole transcriptome sequencing technologies allows a more precise delineation of cellular and molecular substructure in a comprehensive unbiased way. Here we present an investigation whole-transcriptome spatial sequencing in a diverse cohort of ovarian cancer cases. Methods: Three serial 5-micron frozen sections were placed on proprietary 10x Genomics Spatial Transcriptomics (ST) slides and processed using manufacturer specifications. Libraries were sequenced on the Illumina NovaSeq 6000 system and data was processed using the 10X Genomics analytical tools. ST data from each section was analyzed to create spatially defined cellular clusters at 100-micron resolution. Results: ST revealed cellular heterogeneity across the entirety of the tumor microenvironment in an anatomically resolved manner. Bioinformatic tools and molecular pathways to infer tumor purity were used to annotate tumor, immune, and stromal substructures. These data also revealed clear transcriptional substructure in some tumors, where different tumor regions were defined by unique gene sets associated with different molecular processes known to be related to tumorigenesis. Further, we observed clear transcriptional substructure in some tumors, where different tumor regions were enriched with molecular pathways that are associated with tumorigenesis (i.e., DNA Damage Response, and Protein Translation pathways), regions defined by immune infiltration (i.e. CD8+ T cells, T regulatory cells, Macrophages, and B cells), and molecular pathways that are associated with inflammatory signalling (i.e. complement, IL2, IL-10, and IL6 signaling pathways). Conclusion: These approaches highlight the power of spatial whole-transcriptomic approaches in solid tumor studies to help unravel the complexity of heterogeneous cancers and provide a comprehensive characterization of transcriptional substructure within a single tissue section.

Citation Format: Lee D. Gibbs, Stephen R. Williams, Neil I. Weisenfeld, Rania Bassiouni, Nigel F. Delaney, Diane Da Silva, Yifeng Yin, Solomon Rotimi, Jennifer Chew, Meghan Frey, Jing Qian, Heather Miller, Laila Murderspach, Troy McEachron, David Craig, Lynda WOptional Roman, John D. Carpten. Spatial RNA-seq reveals intratumor heterogeneity and transcriptional substructure in a diverse cohort of high-grade ovarian cancers [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr A087.

Abstract 862: Transcriptomics analysis reveals unique immunoinflammatory signatures of nigerian prostate cancer

Background: Prostate cancer (PCa) is the leading cause of cancer death among Nigerian men, with most men presenting late and with high grade disease. Furthermore, improved PCa diagnosis and treatment could rely on genomics-driven precision approaches. Mounting evidence supports potential population enriched molecular features of cancer, however the extent of which is hampered due to a dearth of genomic data in diverse cohorts. This study, therefore, aims at utilizing transcriptomics analysis to deduce transcriptional states in PCa from Nigerian men.

Methodology: RNA was extracted from macro-dissected prostate tumor and adjacent normal tissue from 35 archival formalin fixed paraffin-embedded (FFPE) blocks from Gleason 8-9 cancers, of which 25 had cribriform morphologic architecture. High resolution hybrid-capture mRNA-seq libraries were sequenced using Illumina NovaSeq 6000 system and generated an average of 124 million read pairs per sample. Raw reads were processed using a custom pipeline based upon industry standard algorithms along with the deduction of genetic ancestry. Molecular annotation was also performed to investigate tumor and immune cell heterogeneity.

Result: The Nigerian data were compared with high grade PCa data of Caucasian obtained from TCGA. The Nigerian PCa tumors where characterized with uniquely enriched immune-inflammatory microenvironment which include crosstalk between dendritic cells and natural killer cells, and natural killer cell signaling. While the Nigerian tumors share more features of distal metastatic tumor, their enrichment in NKT Cells is a unique feature.

Conclusion: This represents the first report of RNA-seq analysis of PCa in Sub-Saharan Africa and the unique transcriptomics features of Nigerian PCa presents opportunities for precision intervention in addressing its burden in Nigeria.

Citation Format: Solomon Oladapo Rotimi, Abidemi E. Omonisi, Faruk Mohammed, Paul Jibrin, Babatunde Duduyemi, Daniel B. Olusina, Yili Xu, Yuxin Jin, Xiyu Liu, Guang Q. Xiao, Folakemi Odedina, John Carpten, Renee Reams, Zarko Manojlovic. Transcriptomics analysis reveals unique immunoinflammatory signatures of nigerian prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 862.