Crosstalk between long non coding RNAs, microRNAs and DNA damage repair in prostate cancer: new therapeutic opportunities?

It is increasingly appreciated that transcripts derived from non-coding parts of the human genome, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are key regulators of biological processes both in normal physiology and disease. Their dysregulation during tumourigenesis has attracted significant interest in their exploitation as novel cancer therapeutics. Prostate cancer (PCa), as one of the most diagnosed malignancies and a leading cause of cancer-related death in men, continues to pose a major public health problem. In particular, survival of men with metastatic disease is very poor. Defects in DNA damage response (DDR) pathways culminate in genomic instability in PCa, which is associated with aggressive disease and poor patient outcome. Treatment options for metastatic PCa remain limited. Thus, researchers are increasingly targeting ncRNAs and DDR pathways to develop new biomarkers and therapeutics for PCa. Increasing evidence points to a widespread and biologically-relevant regulatory network of interactions between lncRNAs and miRNAs, with implications for major biological and pathological processes. This review summarises the current state of knowledge surrounding the roles of the lncRNA:miRNA interactions in PCa DDR, and their emerging potential as predictive and diagnostic biomarkers. We also discuss their therapeutic promise for the clinical management of PCa

Subchronic toxicity and behavioural effects of Glycine max (L.) oil emulsion in male rats

The oil of Glycine max commonly known as soybean oil has over the decades grown popularity for its low cholesterol hence its use within the household and commercially for food production has grossly increased. This study was aimed to determine the effects of long term consumption of soybean oil toxicologically and behaviourally. Male albino rats were administered with the vehicle, 5 and 10% oil emulsion for 30 days orally. The rats were subjected to behavioural tests such as novelty-induced behaviour (NIB), learning and memory tests and food intake measurement weekly. At the end of 30 days, rats were anesthetized and carefully dissected and blood sample was taken and analyzed haematogically and biochemically. The liver sample was also taken for biochemical analysis. Histopathological examinations were carried out on the brain, spleen, liver, kidney, lungs and testis samples. The results showed that oral administration of oil caused an increase in food intake, significant effect on NIB but had no effect on learning and memory. There was a significant (p<0.05) reduction in the level of both haemoglobin and PCV in the grouped administered with high dose. Biochemical analysis revealed a significant (p<0.05) increase in triglyceride, ALT, AST levels, with no effect on cholesterol. Histopathological analysis revealed no significant effects on the essential organs tested when compared with the vehicle treated rats. This study conclusively showed that soybean oil has central excitatory effects and there is need for caution when used for a long period since it has significant effects on biochemical parameters

THE ORGANOLEPTIC AND MICROBIAL QUALITY OF SOME HERBAL MEDICINAL PRODUCTS MARKETED IN FREETOWN, SIERRA LEONE.

The WHO has advocated for the integration of herbal medicinal products into the primary health care system of developing countries. Safety, however, is a concern to the drug regulatory bodies. This study was carried out to determine the organoleptic properties and the microbial quality of herbal products available to consumers in the Freetown metropolis of Sierra Leone. Twenty herbal preparations purchased within the Freetown metropolis were assessed for taste, colour, odour, and pH. The microbial load and the presence of pathogens were determined. The residual antibacterial activity of two preparations that showed no microbial contamination was determined using the cup plate method. The ability of a combination of methyl- and propyl-parabens to prevent growth in some of the herbal products was studied. The study showed that 80% of the samples contained mean bacterial and fungal counts ranging from 1.47 x 108 to 9.375 x 108cfu/ml and 3.45x108 to 1.6x109cells/ml, respectively. The bacterial contaminants were predominantly Gram-positive organisms of the genera Bacillus and Staphylococcus. Escherichia coli, Salmonella spp. and Shigella spp. were among the isolated pathogens. The moulds, Aspergillus spp. and Trichoderma harzianum, and the yeasts, Candida albicans and Cryptococcus neoformans, were predominant fungal contaminants. The apparently non-contaminated herbal samples inhibited test organisms while the preservative system completely inhibited growth in the tested samples. The results suggest that many of the herbal medicinal preparations marketed in Freetown are likely to be contaminated with potentially pathogenic microorganisms. The quality of these herbal products may however be improved by the incorporation of appropriate preservatives

Subchronic toxicity and behavioural effects of Glycine max (L.) oil emulsion in male rats

The oil of Glycine max commonly known as soybean oil has over the decades grown popularity for its low cholesterol hence its use within the household and commercially for food production has grossly increased. This study was aimed to determine the effects of long term consumption of soybean oil toxicologically and behaviourally.Male albino rats were administered with the vehicle, 5 and 10% oil emulsion for 30 days orally. The rats were subjected to behavioural tests such as novelty-induced behaviour (NIB), learning and memory tests and food intake measurement weekly. At the end of 30 days, rats were anesthetized and carefully dissected and blood sample was taken and analyzed haematogically and biochemically. The liver sample was also taken for biochemical analysis. Histopathological examinations were carried out on the brain, spleen, liver, kidney, lungs and testis samples.The results showed that oral administration of oil caused an increase in food intake, significant effect on NIB but had no effect on learning and memory. There was a significant (p<0.05) reduction in the level of both haemoglobin and PCV in the grouped administered with high dose. Biochemical analysis revealed a significant (p<0.05) increase in triglyceride, ALT, AST levels, with no effect on cholesterol. Histopathological analysis revealed no significant effects on the essential organs tested when compared with the vehicle treated rats.This study conclusively showed that soybean oil has central excitatory effects and there is need for caution when used for a long period since it has significant effects on biochemical parameters

VASCULAR PERMEABILITY- INCREASING EFFECT OF THE LEAF ESSENTIAL OIL OF OCIMUM GRATISSIMUM LINN AS A MECHANISM FOR ITS WOUND HEALING PROPERTY.

Persistent microvascular hyperpermeability to plasma proteins is a characteristic feature of normal wound healing. Does the leaf essential oil of Ocimum gratissimum heal wounds by promoting this feature? Evan’s blue dye (20mg/kg body weight) in normal saline was administered intravenously through marginal ear vein of experimental rabbits (n=5). Each animal served as its own control. One hour after Evan’s blue dye administration, 0.1ml each of Ocimum oil, histamine dihydrochloride (30µg/ml) and normal saline were randomly administered by intra-dermal injection at the prepared sites on each of the animals. Increase in vascular permeability was assessed by dye effusion test. Analysis of the differences in vascular permeability between treatment groups showed that, Ocimum oil, in intensity and duration, was significantly (

WOUND-HEALING AND POTENTIAL ANTI-KELOIDAL PROPERTIES OF THE LATEX OF CALOTROPIS PROCERA (AITON) ASCLEPIADACEAE IN RABBITS.

Calotropis Procera (CP) has been used in the management of toothache, fresh skin burns, gum bleeding as well as others to make it qualify as a medicinal plant. This study was designed to assess its wound-healing property in rabbits and its potentials for anti keloidal activity.Fresh latex of Calotropis were obtained and evaluated phytochemically. Fifteen male rabbits were used and four excisional wounds were created on each rabbit. The rabbits were divided into five groups of three each. Group 1 was the negative control and received no treatment. The wounds of group 2 animals were treated with 2mL of Calotropis latex; group 3 with 2mL honey; and group 4 with a mixture of 1ml honey and 1 mL of the latex. The animals in group 5 were given 2mg triamcinolone intramuscularly. All the groups had their wounds treated daily for 21 days. The wounds’ diameters were measured on the day of wound creation, thereafter on days 7, 14 and 21 post wound creation. Biopsies of the wounds were taken on days 3 and 21 and viewed histologically. Phytochemical study of the latex revealed the presence of glycosides, tannins and alkaloids. The wounds were found to be significantly (

A non-coding RNA balancing act: miR-346-induced DNA damage is limited by the long non-coding RNA NORAD in prostate cancer

Background: miR‑346 was identified as an activator of Androgen Receptor (AR) signalling that associates with DNA damage response (DDR)‑linked transcripts in prostate cancer (PC). We sought to delineate the impact of miR‑346 on DNA damage, and its potential as a therapeutic agent. Methods: RNA‑IP, RNA‑seq, RNA‑ISH, DNA fibre assays, in vivo xenograft studies and bioinformatics approaches were used alongside a novel method for amplification‑free, single nucleotide‑resolution genome‑wide mapping of DNA breaks (INDUCE‑seq). Results: miR‑346 induces rapid and extensive DNA damage in PC cells ‑ the first report of microRNA‑induced DNA damage. Mechanistically, this is achieved through transcriptional hyperactivation, R‑loop formation and replication stress, leading to checkpoint activation and cell cycle arrest. miR‑346 also interacts with genome‑protective lncRNA NORAD to disrupt its interaction with PUM2, leading to PUM2 stabilisation and its increased turnover of DNA damage response (DDR) transcripts. Confirming clinical relevance, NORAD expression and activity strongly correlate with poor PC clinical outcomes and increased DDR in biopsy RNA‑seq studies. In contrast, miR‑346 is associated with improved PC survival. INDUCE‑seq reveals that miR‑346‑induced DSBs occur preferentially at binding sites of the most highly‑transcriptionally active transcription factors in PC cells, including c‑Myc, FOXA1, HOXB13, NKX3.1, and importantly, AR, resulting in target transcript downregulation. Further, RNA‑seq reveals widespread miR‑346 and shNORAD dysregulation of DNA damage, replication and cell cycle processes. NORAD drives target‑directed miR decay (TDMD) of miR‑346 as a novel genome protection mechanism: NORAD silencing increases mature miR‑346 levels by several thousand‑fold, and WT but not TDMD‑mutant NORAD rescues miR‑346‑induced DNA damage. Importantly, miR‑346 sensitises PC cells to DNA‑damaging drugs including PARP inhibitor and chemotherapy, and induces tumour regression as a monotherapy in vivo, indicating that targeting miR‑346:NORAD balance is a valid therapeutic strategy

Choline kinase alpha as an androgen receptor chaperone and prostate cancer therapeutic target

Background: The androgen receptor (AR) is a major drug target in prostate cancer (PCa). We profiled the AR-regulated kinome to identify clinically relevant and druggable effectors of AR signaling. Methods: Using genome-wide approaches, we interrogated all AR regulated kinases. Among these, choline kinase alpha (CHKA) expression was evaluated in benign (n = 195), prostatic intraepithelial neoplasia (PIN) (n = 153) and prostate cancer (PCa) lesions (n = 359). We interrogated how CHKA regulates AR signaling using biochemical assays and investigated androgen regulation of CHKA expression in men with PCa, both untreated (n = 20) and treated with an androgen biosynthesis inhibitor degarelix (n = 27). We studied the effect of CHKA inhibition on the PCa transcriptome using RNA sequencing and tested the effect of CHKA inhibition on cell growth, clonogenic survival and invasion. Tumor xenografts (n = 6 per group) were generated in mice using genetically engineered prostate cancer cells with inducible CHKA knockdown. Data were analyzed with χ 2 tests, Cox regression analysis, and Kaplan-Meier methods. All statistical tests were two-sided. Results: CHKA expression was shown to be androgen regulated in cell lines, xenografts, and human tissue (log fold change from 6.75 to 6.59, P = .002) and was positively associated with tumor stage. CHKA binds directly to the ligand-binding domain (LBD) of AR, enhancing its stability. As such, CHKA is the first kinase identified as an AR chaperone. Inhibition of CHKA repressed the AR transcriptional program including pathways enriched for regulation of protein folding, decreased AR protein levels, and inhibited the growth of PCa cell lines, human PCa explants, and tumor xenografts. Conclusions: CHKA can act as an AR chaperone, providing, to our knowledge, the first evidence for kinases as molecular chaperones, making CHKA both a marker of tumor progression and a potential therapeutic target for PCa.Mohammad Asim ... Luke A. Selth ... Wayne D. Tilley et al

A reciprocal feedback between the PDZ binding kinase and androgen receptor drives prostate cancer

Elucidation of mechanisms underlying the increased androgen receptor (AR) activity and subsequent development of aggressive prostate cancer (PrCa) is pivotal in developing new therapies. Using a systems biology approach, we interrogated the AR-regulated proteome and identified PDZ binding kinase (PBK) as a novel AR-regulated protein that regulates full-length AR and AR variants (ARVs) activity in PrCa. PBK overexpression in aggressive PrCa is associated with early biochemical relapse and poor clinical outcome. In addition to its carboxy terminus ligand-binding domain, PBK directly interacts with the amino terminus transactivation domain of the AR to stabilise it thereby leading to increased AR protein expression observed in PrCa. Transcriptome sequencing revealed that PBK is a mediator of global AR signalling with key roles in regulating tumour invasion and metastasis. PBK inhibition decreased growth of PrCa cell lines and clinical specimen cultured ex vivo. We uncovered a novel interplay between AR and PBK that results in increased AR and ARVs expression that executes AR-mediated growth and progression of PrCa, with implications for the development of PBK inhibitors for the treatment of aggressive PrCa.Anne Y. Warren, Charlie E. Massie, Kate Watt, Katarina Luko ... Luke A. Selth ... Wayne D. Tilley ... et al