Non-Coding RNAs in Human Cancer and Other Diseases: Overview of the Diagnostic Potential.

Non-coding RNAs (ncRNAs) are abundant single-stranded RNA molecules in human cells, involved in various cellular processes ranging from DNA replication and mRNA translation regulation to genome stability defense. MicroRNAs are multifunctional ncRNA molecules of 18-24 nt in length, involved in gene silencing through base-pair complementary binding to target mRNA transcripts. piwi-interacting RNAs are an animal-specific class of small ncRNAs sized 26-31 nt, responsible for the defense of genome stability via the epigenetic and post-transcriptional silencing of transposable elements. Long non-coding RNAs are ncRNA molecules defined as transcripts of more than 200 nucleotides, their function depending on localization, and varying from the regulation of cell differentiation and development to the regulation of telomere-specific heterochromatin modifications. The current review provides recent data on the several forms of small and long non-coding RNA's potential to act as diagnostic, prognostic or therapeutic target for various human diseases.

Classic and New Markers in Diagnostics and Classification of Breast Cancer.

Breast cancer remains the most frequently diagnosed form of female's cancer, and in recent years it has become the most common cause of cancer death in women worldwide. Like many other tumours, breast cancer is a histologically and biologically heterogeneous disease. In recent years, considerable progress has been made in diagnosis, subtyping, and complex treatment of breast cancer with the aim of providing best suited tumour-specific personalized therapy. Traditional methods for breast cancer diagnosis include mammography, MRI, biopsy and histological analysis of tumour tissue in order to determine classical markers such as estrogen and progesterone receptors (ER, PR), cytokeratins (CK5/6, CK14, C19), proliferation index (Ki67) and human epidermal growth factor type 2 receptor (HER2). In recent years, these methods have been supplemented by modern molecular methodologies such as next-generation sequencing, microRNA, in situ hybridization, and RT-qPCR to identify novel molecular biomarkers. MicroRNAs (miR-10b, miR-125b, miR145, miR-21, miR-155, mir-30, let-7, miR-25-3p), altered DNA methylation and mutations of specific genes (p16, BRCA1, RASSF1A, APC, GSTP1), circular RNA (hsa_circ_0072309, hsa_circRNA_0001785), circulating DNA and tumour cells, altered levels of specific proteins (apolipoprotein C-I), lipids, gene polymorphisms or nanoparticle enhanced imaging, all these are promising diagnostic and prognostic tools to disclose any specific features from the multifaceted nature of breast cancer to prepare best suited individualized therapy.

Global Longitudinal Strain and Strain Rate in Type Two Diabetes Patients with Chronic Heart Failure: Relevance to Osteoprotegerin.

BACKGROUND: Biomechanical stress and inflammatory biomarkers relate to global contractility dysfunction; however, adding these biomarkers into a risk model constructed on clinical data does not improve its prediction value in chronic heart failure (CHF). AIM: The aim of this study was to evaluate whether biomarkers predict declining of left ventricular global contractility function in diabetic patients with ischemia-induced CHF. PATIENTS AND METHODS: The study retrospectively evolved 54 diabetic patients who had systolic or diastolic ischemia-induced CHF that was defined as left-ventricular ejection fraction (LVEF) ≤45% or 46-55% respectively assessed by quantitative echocardiography and other conventional criteria according to current clinical guidelines. Two-dimensional transthoracic echocardiography and tissue Doppler imaging were performed according to a conventional method. Radial, longitudinal, and circumferential strain and strain rate values were obtained by speckle-tracking Imaging analysis of both LV short axis and long axis views. Serum adiponectin, NT-pro brain natriuretic peptide (BNP), osteoprotegerin, and hs- C-reactive protein (CRP) were determined at baseline by ELISA. RESULTS: We found lower global longitudinal strain and strain rate in diabetic patients with LVEF <45% than these in diabetic patients that did not have LVEF (Р=0.001 for all cases). Multivariate logistic regression analysis showed that NT-proBNP (r=0.432; P=0.001 and r=0.402; P=0.001, respectively), osteoprotegerin (r=0.422; P=0.001 and r=0.401; P=0.001, respectively), hs-CRP (r=0.408; P=0.001 and r=0.404; P=0.001, respectively) were independently inversely associated with global longitudinal strain and strain rate in CHF patients. CONCLUSION: We suggest that osteoprotegerin may be useful in improving the NT-proBNP based model as predictor of decreased global contractility function in diabetic patients with CHF.

Resuscitation and auto resuscitation by airway reflexes in animals.

Various diseases often result in decompensation requiring resuscitation. In infants moderate hypoxia evokes a compensatory augmented breath - sigh and more severe hypoxia results in a solitary gasp. Progressive asphyxia provokes gasping respiration saving the healthy infant - autoresuscitation by gasping. A neonate with sudden infant death syndrome, however, usually will not survive. Our systematic research in animals indicated that airway reflexes have similar resuscitation potential as gasping respiration. Nasopharyngeal stimulation in cats and most mammals evokes the aspiration reflex, characterized by spasmodic inspiration followed by passive expiration. On the contrary, expiration reflex from the larynx, or cough reflex from the pharynx and lower airways manifest by a forced expiration, which in cough is preceded by deep inspiration. These reflexes of distinct character activate the brainstem rhythm generators for inspiration and expiration strongly, but differently. They secondarily modulate the control mechanisms of various vital functions of the organism. During severe asphyxia the progressive respiratory insufficiency may induce a life-threatening cardio-respiratory failure. The sniff- and gasp-like aspiration reflex and similar spasmodic inspirations, accompanied by strong sympatho-adrenergic activation, can interrupt a severe asphyxia and reverse the developing dangerous cardiovascular and vasomotor dysfunctions, threatening with imminent loss of consciousness and death. During progressive asphyxia the reversal of gradually developing bradycardia and excessive hypotension by airway reflexes starts with reflex tachycardia and vasoconstriction, resulting in prompt hypertensive reaction, followed by renewal of cortical activity and gradual normalization of breathing. A combination of the aspiration reflex supporting venous return and the expiration or cough reflex increasing the cerebral perfusion by strong expirations, provides a powerful resuscitation and autoresuscitation potential, proved in animal experiments. They represent a simple but unique model tested in animal experiments.

Reversal of functional disorders by aspiration, expiration, and cough reflexes and their voluntary counterparts.

Agonal gasping provoked by asphyxia can save ~15% of mammals even from untreated ventricular fibrillation (VF), but it fails to revive infants with sudden infant death syndrome (SIDS). Our systematic study of airway reflexes in cats and other animals indicated that in addition to cough, there are two distinct airway reflexes that may contribute to auto-resuscitation. Gasp- and sniff-like spasmodic inspirations (SIs) can be elicited by nasopharyngeal stimulation, strongly activating the brainstem generator for inspiration, which is also involved in the control of gasping. This "aspiration reflex" (AspR) is characterized by SI without subsequent active expiration and can be elicited during agonal gasping, caused by brainstem trans-sections in cats. Stimulation of the larynx can activate the generator for expiration to evoke the expiration reflex (ExpR), manifesting with prompt expiration without preceding inspiration. Stimulation of the oropharynx and lower airways provokes the cough reflex (CR) which results from activating of both generators. The powerful potential of the AspR resembling auto-resuscitation by gasping can influence the control mechanisms of vital functions, mediating reversal of various functional disorders. The AspR in cats interrupted hypoxic apnea, laryngo- and bronchospasm, apneusis and even transient asphyxic coma, and can normalize various hypo- and hyper-functional disorders. Introduction of a nasogastric catheter evoked similar SIs in premature infants and interrupted hiccough attacks in adults. Coughing on demand can prevent anaphylactic shock and resuscitate the pertinent subject. Sniff representing nasal inspiratory pressure and maximal inspiratory and expiratory pressures (MIP and MEP) are voluntary counterparts of airway reflexes, and are useful for diagnosis and therapy of various cardio-respiratory and neuromuscular disorders.

Multigenerational lifetime low-dose exposure to heavy metals on selected reproductive parameters in rats.

The aim of the present investigation was to evaluate the effects of multigenerational (P, F1 and F2) exposure to low doses of lead, mercury and cadmium dissolved in tap water on the reproductive potency of Wistar rats and the physical health of their progeny. The animals were divided into 4 groups - control (C) and 3 groups intoxicated by metals (Pb, 100 µM; Hg, 1 µM; Cd, 20 µM, respectively). Females gave births from the 13th to the 78th week of experiment. Parameters of reprotoxicity such as number of litters, total number of neonates (assigned in the birth day), and number of weanlings (28th day after birth) were measured in 13-week intervals. Our data show an increase of most reproductive parameters in parental generation of rats exposed to lead and mercury and a decrease of reproductive parameters of exposed animals in subsequent F1 and F2 generations. Exposure to cadmium had no significant effect on the reproductive parameters in comparison with the control group.

The effect of hypoxic myocardial preconditioning is highly dependent on the light-dark cycle in Wistar rats.

BACKGROUND: Cardioprotective effects by hypoxic preconditioning are well known mainly through in vitro experiments. However, the chronobiological aspects of phenomenon of cardioprotection by hypoxic preconditioning have not been studied in in vitro and in vivo experiments, and there are no consistent data regarding the daytime dependence of preconditioning effects. AIM: To determine the protective effects of myocardial preconditioning applied during the dark (active) part of the day regimen, and to obtain an understanding concerning chronophysiological aspects of this phenomenon in in vivo rat experiments. METHODS: The present study was designed to evaluate the effects of cardiac preconditioning induced by one to three cycles (1PC to 3PC) of asphyxia (5 min of artificial hypoventilation [tidal volume 0.5 mL/100 g of body weight, 20 breaths/min]) and reoxygenation (5 min of artificial ventilation [tidal volume 1 mL/100 g of body weight, 40 breaths/min]) on ventricular arrhythmia threshold (VAT) in the dark (active) part of the day regimen in anesthetized Wistarrats (ketamine/xylazine100 mg/15 mg/kg, intramuscularly, open chest experiments) after the adaptation to the light-dark cycle (12 h:12 h). RESULTS: In the dark part of the day, hypoventilation-induced asphyxia caused a decrease of the VAT in the control animals, as well as in the 1PC and 2PC groups (P<0.001), which showed only incomplete recovery of the VAT after reoxygenation. In the 3PC group, the VAT values remained close to the preasphyxic level during both types of ventilation. CONCLUSIONS: Preconditioning by hypoventilation-induced asphyxia had little effect on the changes of the electrical stability of the heart in the dark (active) part of the day regimen in in vivo rat experiments.

Chronophysiological view on changes of the electrical stability of the heart and heart rate under pentobarbital sodium and ketamine/xylazine anesthesia in a hypoventilation-reoxygenation rat model.

OBJECTIVES: To determine the effect of the light-dark cycle (LD) and type of anesthetic agent used on changes in the electrical stability of the heart in disorders of pulmonary ventilation. METHODS: The ventricular arrhythmia threshold (VAT) and heart rate (HR) were measured in anesthetized female Wistar rats adapted to an LD regimen of 12 h:12 h (pentobarbital sodium 30 mg/kg, intraperitoneally, or ketamine/xylazine 100 mg/15 mg/kg, intramuscularly; open chest experiments) under artificial normoventilation (tidal volume 1 mL/100 g, respiratory rate 40 breaths/min) and during 20 min of hypoventilation (tidal volume 0.5 mL/100 g, respiratory rate 20 breaths/min) followed by 20 min of reoxygenation. Control and experimental groups were set according to LD cycle adaptation and type of anesthesia used: light control pentobarbital sodium group, n=67; dark control pentobarbital sodium group n=50; light hypoventilation-reoxygenation (hypo-reoxy) pentobarbital sodium group, n=26; dark hypo-reoxy pentobarbital sodium group, n=16; light control ketamine/xylazine group, n=90; dark control ketamine/xylazine group, n=57; light hypo-reoxy ketamine/xylazine group, n=13; and dark hypo-reoxy ketamine/xylayine group, n=18. RESULTS: In the control groups, the LD cycle only had an effect on animals under pentobarbital sodium anesthesia (P<0.001). During hypoventilation, the VAT was significantly lower in animals under both types of anesthesia and during the light period of the LD cycle than in the control groups. During the light part of the LD cycle, the period of reoxygenation increased VAT values (P<0.001). However, during the dark period of the LD cycle the VAT values decreased. Heart rate was significantly lower in the ketamine/xylazine groups than in the pentobarbital sodium groups during the light and dark periods of the LD cycle, respectively (P<0.001). CONCLUSIONS: The mechanisms mediating the effects of pentobarbital sodium anesthesia on myocardial vulnerability likely depend on the LD cycle, in contrast with the mechanisms that mediate the effects of ketamine/xylazine anesthesia, in female Wistar rats.