Pitfalls and Opportunities for Epigenomic Analyses Focused on Disease Diagnosis, Prognosis, and Therapy

Multi-Omics Profiling for Health

The world has witnessed a steady rise in both non-infectious and infectious chronic diseases, prompting a cross-disciplinary approach to understand and treating disease. Current medical care focuses on treating people after they become patients rather than preventing illness, leading to high costs in treating chronic and late-stage diseases. Additionally, a "one-size-fits all" approach to health care does not take into account individual differences in genetics, environment, or lifestyle factors, decreasing the number of people benefiting from interventions. Rapid advances in omics technologies and progress in computational capabilities have led to the development of multi-omics deep phenotyping, which profiles the interaction of multiple levels of biology over time and empowers precision health approaches. This review highlights current and emerging multi-omics modalities for precision health and discusses applications in the following areas: genetic variation, cardio-metabolic diseases, cancer, infectious diseases, organ transplantation, pregnancy, and longevity/aging. We will briefly discuss the potential of multi-omics approaches in disentangling host-microbe and host-environmental interactions. We will touch on emerging areas of electronic health record and clinical imaging integration with muti-omics for precision health. Finally, we will briefly discuss the challenges in the clinical implementation of multi-omics and its future prospects.

Analysis of pharmacogenomic very important pharmacogenomic variants: CYP3A5, ACE, PTGS2 and NAT2 genes in Chinese Bai population

Aim: Our study aimed to screen the genotype frequencies of very important pharmacogenomic (VIP) mutations and identify their differences between Bai and other populations. Materials & methods: We selected 66 VIP variants from PharmGKB (www.pharmgkb.org/) for genotyping. χ2 test was used to identify differences in loci between these populations and Fst values of Bai and the other 26 populations were analyzed. Results: Our study showed that the frequencies of SNPs of CYP3A5, ACE, PTGS2 and NAT2 differed significantly from those of the other 26 populations. At the same time, we found that some VIP variants may affect the metabolism of drugs and the genetic relationship between the Bai population and East Asian populations was found to be the closest. Conclusion: By comparing the genotype frequencies of different populations, the loci with significant differences were identified and discussed, providing a theoretical basis for individualized drug use in the Bai ethnic population.

Family-effects in the epigenomic response of red blood cells to a challenge test in the European sea bass (Dicentrarchus labrax, L.)

Abstract

Background

In fish, minimally invasive blood sampling is widely used to monitor physiological stress with blood plasma biomarkers. As fish blood cells are nucleated, they might be a source a potential new markers derived from ‘omics technologies. We modified the epiGBS (epiGenotyping By Sequencing) technique to explore changes in genome-wide cytosine methylation in the red blood cells (RBCs) of challenged European sea bass (Dicentrarchus labrax), a species widely studied in both natural and farmed environments.

Results

We retrieved 501,108,033 sequencing reads after trimming, with a mean mapping efficiency of 73.0% (unique best hits). Minor changes in RBC methylome appeared to manifest after the challenge test and a family-effect was detected. Only fifty-seven differentially methylated cytosines (DMCs) close to 51 distinct genes distributed on 17 of 24 linkage groups (LGs) were detected between RBCs of pre- and post-challenge individuals. Thirty-seven of these genes were previously reported as differentially expressed in the brain of zebrafish, most of them involved in stress coping differences. While further investigation remains necessary, few DMC-related genes associated to the Brain Derived Neurotrophic Factor, a protein that favors stress adaptation and fear memory, appear relevant to integrate a centrally produced stress response in RBCs.

Conclusion

Our modified epiGBS protocol was powerful to analyze patterns of cytosine methylation in RBCs of D. labrax and to evaluate the impact of a challenge using minimally invasive blood samples. This study is the first approximation to identify epigenetic biomarkers of exposure to stress in fish.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07420-9.

Pharmacogenomics Biomarkers of Soft Tissue Sarcoma Therapies

Soft tissue sarcomas (STS) are heterogeneous rare malignancies comprising ~1% of all solid cancers in adults and including more than 70 histological and molecular subtypes with different pathological and clinical development characteristics. Over the last two decades, the increased knowledge of the new molecular and genomic mechanisms of different STS histotypes allowed for a reclassification of these tumors and consequently to the development of novel chemotherapeutic agents. Generally, surgery, in combination with radiotherapy only in selected cases of localized disease, represents the most common treatment of primary STS, whereas the principal treatment modality for locally advanced or metastatic disease is first-line chemotherapy. The principal treatment for the preponderance of STS patients is usually an anthracycline (epirubicin and doxorubicin) in monotherapy or in combination with other drug novel chemotherapeutic agents. However, survival for treated patients with metastatic disease is poor, and a 2-years survival rate is about 30%. In this scenario, Pharmacogenomics (PGx) biomarkers that can predict drug response play an important role in the improvement of molecular diagnostics in clinical routines and contribute to elucidating the genetic basis for the differences in treatment efficacy and toxicity among STS patients. This review focuses on recent insight in the PGx biomarkers that have been described to modulate responsiveness and toxicity parameters of conventional and new chemotherapeutics drugs in several STS histotypes.

Novel genetic and epigenetic factors of importance for inter-individual differences in drug disposition, response and toxicity

Individuals differ substantially in their response to pharmacological treatment. Personalized medicine aspires to embrace these inter-individual differences and customize therapy by taking a wealth of patient-specific data into account. Pharmacogenomic constitutes a cornerstone of personalized medicine that provides therapeutic guidance based on the genomic profile of a given patient. Pharmacogenomics already has applications in the clinics, particularly in oncology, whereas future development in this area is needed in order to establish pharmacogenomic biomarkers as useful clinical tools. In this review we present an updated overview of current and emerging pharmacogenomic biomarkers in different therapeutic areas and critically discuss their potential to transform clinical care. Furthermore, we discuss opportunities of technological, methodological and institutional advances to improve biomarker discovery. We also summarize recent progress in our understanding of epigenetic effects on drug disposition and response, including a discussion of the only few pharmacogenomic biomarkers implemented into routine care. We anticipate, in part due to exciting rapid developments in Next Generation Sequencing technologies, machine learning methods and national biobanks, that the field will make great advances in the upcoming years towards unlocking the full potential of genomic data.

Pharmacoepigenetics and Toxicoepigenetics: Novel Mechanistic Insights and Therapeutic Opportunities

Pharmacological treatment and exposure to xenobiotics can cause substantial changes in epigenetic signatures. The majority of these epigenetic changes, caused by the compounds in question, occur downstream of transcriptional activation mechanisms, whereby the epigenetic alterations can create a transcriptional memory and stably modulate cell function. The increasing understanding of epigenetic mechanisms and their importance in disease has prompted the development of therapeutic interventions that target epigenetic modulatory mechanisms, particularly in oncology where inhibitors of epigenetic-modifying proteins (epidrugs) have been successfully used in treatment, mostly in combination with standard-of-care chemotherapy, either provoking direct cytotoxicity or inhibiting resistance to anticancer drugs. In addition, emerging methods for detecting epigenetically modified DNA in bodily fluids may provide information about tumor phenotype or drug treatment success. However, it is important to note that many technical pitfalls, such as the nondeconvolution of methylcytosine and hydroxymethylcytosine, compromise epigenetic analyses and the interpretation of results. In this review, we provide an update on the field, with an emphasis on the novel therapeutic opportunities made possible by epidrugs.