Assessing the suitability of miRNA-142-5p and miRNA-541 for bloodstain deposition timing

Research progress and potential application of microRNA and other non-coding RNAs in forensic medicine

At present, epigenetic markers have been extensively studied in various fields and have a high value in forensic medicine due to their unique mode of inheritance, which does not involve DNA sequence alterations. As an epigenetic phenomenon that plays an important role in gene expression, non-coding RNAs (ncRNAs) act as key factors mediating gene silencing, participating in cell division, and regulating immune response and other important biological processes. With the development of molecular biology, genetics, bioinformatics, and next-generation sequencing (NGS) technology, ncRNAs such as microRNA (miRNA), circular RNA (circRNA), long non-coding RNA (lncRNA), and P-element induced wimpy testis (PIWI)-interacting RNA (piRNA) are increasingly been shown to have potential in the practice of forensic medicine. NcRNAs, mainly miRNA, may provide new strategies and methods for the identification of tissues and body fluids, cause-of-death analysis, time-related estimation, age estimation, and the identification of monozygotic twins. In this review, we describe the research progress and application status of ncRNAs, mainly miRNA, and other ncRNAs such as circRNA, lncRNA, and piRNA, in forensic practice, including the identification of tissues and body fluids, cause-of-death analysis, time-related estimation, age estimation, and the identification of monozygotic twins. The close links between ncRNAs and forensic medicine are presented, and their research values and application prospects in forensic medicine are also discussed.

MicroRNAs: An Update of Applications in Forensic Science

MicroRNAs (miRNAs) are a class of non-coding RNAs containing 18–24 nucleotides that are involved in the regulation of many biochemical mechanisms in the human body. The level of miRNAs in body fluids and tissues increases because of altered pathophysiological mechanisms, thus they are employed as biomarkers for various diseases and conditions. In recent years, miRNAs obtained a great interest in many fields of forensic medicine given their stability and specificity. Several specific miRNAs have been studied in body fluid identification, in wound vitality in time of death determination, in drowning, in the anti-doping field, and other forensic fields. However, the major problems are (1) lack of universal protocols for diagnostic expression testing and (2) low reproducibility of independent studies. This review is an update on the application of these molecular markers in forensic biology.

Inhibition of glioblastoma cell invasion by hsa-miR-145-5p and hsa-miR-31-5p co-overexpression in human mesenchymal stem cells

OBJECTIVE

Human bone marrow–derived mesenchymal stem cells (hMSCs) show tropism for brain tumors and may be a useful vehicle for drug or gene delivery to malignant gliomas. Recently, some microRNAs (miRNAs) have been shown to suppress the invasiveness of malignant gliomas.

METHODS

To test their potential to become vehicles for the delivery of miRNA to malignant gliomas, hMSCs were engineered so that hMSC secretion of miRNAs that inhibit glioma cell invasion was enabled without altering the hMSC tropism for glioma cells.

RESULTS

In coculture, hMSCs cotransfected with hsa-miR-145-5p and -31-5p miRNAs showed markedly reduced invasion by U87 glioma cells in a contact-dependent manner both in vitro and ex vivo, with invasion of hMSCs cotransfected with these 2 miRNAs by the U87 cells reduced to 60.7% compared with control cells. According to a Matrigel invasion assay, the tropism of the hMSCs for U87 cells was not affected. In glioma cell lines U251 and LN229, hMSCs exhibited tropism in vivo, and invasion of hMSCs cotransfected with hsa-miR-145-5p and -31-5p was also significantly less than that of control cells. When U87 cells were coimplanted into the striatum of organotypic rat brain slices with hMSCs cotransfected with hsa-miR-145 and -31-5p, the relative invasive area decreased by 37.1%; interestingly, these U87 cells showed a change to a rounded morphology that was apparent at the invasion front. Whole-genome microarray analysis of the expression levels of 58,341 genes revealed that the co-overexpression of hsa-miR-145-5p and -31-5p downregulated FSCN1 expression in U87 cells.

CONCLUSIONS

This study demonstrates that miRNA overexpression in hMSCs can alter the function of glioma cells via contact-dependent transfer. Co-overexpression of multiple miRNAs may be a useful and novel therapeutic strategy. The study results suggest that hMSCs can be applied as a delivery vehicle for miRNAs.

Detectability, visualization, and DNA analysis of bloodstains after repainting the walls

A recurrent observation in forensic casework is that culprits and/or their abettors attempt to remove or mask bloodstain patterns, e.g., by painting the walls. The present study was designed to elucidate whether luminol treatment of bloodstains on (a) plastered and (b) wallpapered walls may help with the visualization of respective patterns after being repainted beyond macroscopic recognition. Furthermore, wallpaper punches of luminol-positive spots were analyzed for DNA. The experiments showed that the prospects for visualization after a four- to sixfold paint application declined considerably as the drying time of the paint increased. A compelling explanation for this observation is that paint becomes increasingly resistant to water during the drying process after paint application. In these cases, moistening the surface in question with distilled water for 15 min has been proven to be a promising pretreatment before luminol application. DNA analysis revealed full STR profiles in 74% of luminol-positive wallpaper punches, whereas rubs of the aforementioned positively tested regions (luminol and human blood pretests) demonstrated negative results.

Circulating miR-200-family micro-RNAs have altered plasma levels in patients with endometriosis and vary with blood collection time

OBJECTIVE

To determine whether circulating micro-RNA (miR) 200a, miR-200b, and miR-141 have altered levels in patients with endometriosis compared with control individuals.

DESIGN

Experimental laboratory study.

SETTING

University.

PATIENT(S)

Patients with endometriosis (n = 61), laparoscopically confirmed endometriosis-free women (n = 35), and self-reported healthy women (n = 30) were included in the study.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Plasma miRNA levels in endometriosis patients and control subjects.

RESULT(S)

We found that the levels of studied miRNAs varied with blood collection time, being lower in the morning than in the evening. When blood collection time was taken into account, the results revealed significantly lower levels of miR-200a and miR-141 in the evening plasma samples of women with endometriosis compared with surgically confirmed disease-free patients. However, the evening-sample levels of all three miRNAs were significantly lower in patients with stage I-II endometriosis than in endometriosis-free control subjects. In cases of stage III-IV endometriosis, only miR-200a levels were significantly lower compared with patients without endometriosis. Circulating miR-200a showed the best discriminative power to differentiate women with endometriosis from patients with similar complaints but without the disease.

CONCLUSION(S)

Our findings suggest that miR-200a and miR-141 have a potential as novel noninvasive biomarkers for endometriosis. In addition, we found that the plasma miR-200a, miR-200b and miR-141 levels vary with blood sampling time, so it is important to take the sample collection time into account when studying miRNAs as biomarkers.

AATF RNome has the potential to define post mortem interval

Keeping in view the fact that the circadian rhythm governs human behavioral characteristics, metabolism and body function, the present study was directed to explore whether or not there exists any cooperativity between AATF RNome (comprising AATF mRNA and its encoded microRNA miR-2909) rhythmicity and post mortem interval (PMI). Such a study unambiguously revealed that circadian rhythm exhibited by AATF RNome has a direct correlation with PMI in Balb/c mice. AATF RNome has the potential to act as biomarker for PMI with reasonably good accuracy and hence may turn out to be of crucial importance in forensic investigation.