Considerable efforts have been exerted to implement Pharmacogenomics (PGx), the study of interindividual variations in DNA sequence related to drug response, into routine clinical practice. In this article, we first briefly describe PGx and its role in improving treatment outcomes. We then propose an approach to initiate clinical PGx in the hospital setting. One should first evaluate the available PGx evidence, review the most relevant drugs, and narrow down to the most actionable drug-gene pairs and related variant alleles. This is done based on data curated and evaluated by experts such as the pharmacogenomics knowledge implementation (PharmGKB) and the Clinical Pharmacogenetics Implementation Consortium (CPIC), as well as drug regulatory authorities such as the US Food and Drug Administration (FDA) and European Medicinal Agency (EMA). The next step is to differentiate reactive point of care from preemptive testing and decide on the genotyping strategy being a candidate or panel testing, each of which has its pros and cons, then work out the best way to interpret and report PGx test results with the option of integration into electronic health records and clinical decision support systems. After test authorization or testing requirements by the government or drug regulators, putting the plan into action involves several stakeholders, with the hospital leadership supporting the process and communicating with payers, the pharmacy and therapeutics committee leading the process in collaboration with the hospital laboratory and information technology department, and healthcare providers (HCPs) ordering the test, understanding the results, making the appropriate therapeutic decisions, and explaining them to the patient. We conclude by recommending some strategies to further advance the implementation of PGx in practice, such as the need to educate HCPs and patients, and to push for more tests’ reimbursement. We also guide the reader to available PGx resources and examples of PGx implementation programs and initiatives.
Breast cancer (BC) is the most predominant type of cancer among women. The aim of this study is to find new biomarkers that can help in early detection of BC, especially for those who are too young to be screened using mammography as per guidelines. Using microRNA microarray, we previously showed dysregulation of 74 microRNAs in tumors from early BC patients as compared with normal adjacent tissues, which we were interested in studying in blood circulation. In this study, we investigated the expression of 12 microRNA (miR-21/miR-155/miR-23a/miR-130a/miR-145/miR-425-5p/miR-139-5p/miR-451/miR-195/miR-125b/miR-100, and miR-182) in the plasma of 41 newly diagnosed Lebanese BC patients with early invasive ductal carcinoma as compared with 32 healthy controls. Total RNA was extracted from plasma, and expression levels of miRNA of interest were measured using RT-qPCR followed by statistical analysis; miR-21, miR-155, miR-23a, miR-130a, miR-145, miR-425-5p, and miR-139-5p were significantly upregulated and miR-451 was significantly downregulated, in the plasma of BC patients as compared with healthy controls. The positively correlated miR-23a, miR-21, and miR-130a had a high diagnostic accuracy (86%). Importantly, the combination of miR-145/miR-425-5p/miR-139-5p/miR-130a scored the highest diagnostic accuracy of 95% with AUC = 0.97 (sensitivity 97% and specificity 91%). MicroRNAs are promising non-invasive diagnostic biomarkers for early-stage BC with the panel of miR-145/miR-425-5p/miR-139-5p/miR-130a having the highest diagnostic accuracy.
29 May 2019 in British Journal of Clinical Pharmacology
Aims: Eight years ago, a paper‐based survey was administered during the World Pharma 2010 meeting, asking about the challenges of implementing pharmacogenetics (PGx) in clinical practice. The data collected at the time gave an idea about the progress of this implementation and what still needs to be done. Since then, although there have been major initiatives to push PGx forward, PGx clinical implementation may still be facing different challenges in different parts of the world. Our aim was therefore to distribute a follow‐up international survey in electronic format to elucidate an overview on the current stage of implementation, acceptance and challenges of PGx in academic institutions around the world.Methods: This is an online anonymous LimeSurvey‐based study launched on 11 November 2018. Survey questions were adapted from the initially published manuscript in 2010. An extensive web search for worldwide scientists potentially involved in PGx research resulted in a total of 1973 names. Countries were grouped based on the Human Development Index.Results: There were 204 respondents from 43 countries. Despite the wide availability of PGx tests, the consistently positive attitude towards their applications and advances in the field, progress of the clinical implementation of PGx still faces many challenges all around the globe.Conclusions: Clinical implementation of PGx started over a decade ago but there is a gap in progress around the globe and discrepancies between the challenges reported by different countries, despite some challenges being universal. Further studies on ways to overcome these challenges are warranted.
Background: Acute lymphoblastic leukemia (ALL) is the most common cancer seen in children worldwide and in the Middle East. Although there have been major advances in treatment approaches for childhood ALL, serious toxicities do occur but with significant inter-individual variability. The aim of this study is to measure the frequency of polymorphisms in candidate genes involved in 6-Mercaptopurine (6-MP) disposition in a combined cohort of Middle Eastern Children with ALL, and evaluate whether these polymorphisms predict 6-MP intolerance and toxicity during ALL maintenance therapy. Methods: The study includes children treated for ALL on two treatment protocols from two cohorts; one from Lebanon (N = 136) and another from Kurdistan province of Iran (N = 74). Genotyping for the following six candidate genetic polymorphisms: ITPA 94C > A (rs1127354) and IVS2+21A > C (rs7270101), TPMT*2 238G > C (rs1800462), TPMT*3B 460G > A (rs1800460) and *3C 719A > G (rs1142345), and NUDT15 415C > T (rs116855232) was performed and analyzed in association with 6-MP dose intensity and toxicity. Results: As expected, TPMT and NUDT15 variants were uncommon. As for ITPA, both polymorphisms were more common in the Lebanese as compared to the Kurdish cohort with a minor allele frequency of 0.05 for 94C > A and 0.14 for IVS2+21A > C in the Lebanese only (N = 121), and of 0.01 for either ITPA polymorphism in Kurds. The most significant toxic effects were depicted with the NUDT15 polymorphism with a median 6-MP dose intensity of 33.33%, followed by 46.65% for TPMT*3A polymorphism, followed by 65.33% for two ITPA risk allele carriers and 74% for one ITPA risk allele carriers, in comparison to a median of 100% for the homozygous wild type in the combined cohort (P < 0.001). In addition, the onset of febrile neutropenia was significantly higher in variant allele carriers in the combined cohorts. Conclusions: These data confirm the predictive role of TPMT, NUDT15, and ITPA in 6-MP intolerance in Middle Eastern children with ALL. Given the relatively high frequency of ITPA variants in our study and their significant association with 6-MP dose intensity, we recommend that physicians consider genotyping for ITPA variants in conjunction with TPMT and NUDT15 prior to 6-MP therapy in these children.
Background: Bisphenol A (BPA), an estrogen-like endocrine disruptor used in plastics, has been associated with development and promotion of breast cancer, so plastic manufacturers shifted towards less-studied analogs, BPF and BPS. Studying the associated DNA methylome-wide mechanisms of these derivatives is timely, particularly in comparison with BPA.Methods: We assessed proliferation, cell cycle, and migration of breast cancer cells (estrogen receptor (ER)-positive: MCF-7 and ER-negative: MDA-MB-231) treated with BPF and BPS ± estrogen receptor inhibitor (ERI) in comparison to BPA ± ERI. RNA expression and activity of DNA (de)methylation enzymes andLINE-1methylation were quantified. DNA methylome-wide analysis was evaluated in bisphenol-exposed cells and compared to clinical breast cancer data.Results: The three bisphenols caused ER-dependent increased proliferation and migration of MCF-7 but not MDA-MB-231 cells, with BPS being 10 times less potent than BPA and BPF. Although they have similar chemical structures, the three bisphenols induced differential DNA methylation alterations at several genomic clusters of or single CpG sites, with the majority of these being ER-dependent. At equipotent doses, BPA had the strongest effect on the methylome, followed by BPS then BPF. No pathways were enriched for BPF while BPA- and BPS-induced methylome alterations were enriched in focal adhesion, cGMP-PKG, and cancer pathways, which were also dysregulated in methylome-wide alterations comparing ER-positive breast cancer samples to adjacent normal tissues.Conclusions: The three bisphenols have important epigenetic effects in breast cell lines, with those of BPA and BPS overlapping with cancer-related pathways in clinical breast cancer models. Hence, further investigation of their safety is warranted.
1 October 2011 in The Journal of Clinical Pharmacology