Prediction of personalized drugs based on genetic variations provided by DNA sequencing technologies

Recent reports of death and illness caused by adverse drug reactions have boosted rational drug design research. It has been shown through sequencing of the entire human genome that human genetic variations play a key role in adverse reactions to drugs as well as in differences in the effectiveness of drug treatments. The advent of high-throughput DNA sequencing technologies with bioinformatics of system biology have allowed the easy identification of genetic variations and all other pharmacogenetic variants in a single assay, thus permitting truly personalized drug treatment. This would be particularly valuable for many patients with chronic diseases who must take many medications concurrently. In this review, we have focused on pharmacogenomics for the prediction of variable drug responses between individuals with relevant genetic variations through new DNA sequencing technologies and provided directions for personalized drug therapy in the future.     

Pharmacogenomics and systems biology of membrane transporters

Membrane transporters are essential for fundamental cellular functions and normal physiological processes. These molecules influence drug absorption and distribution, and play key roles in drug therapeutic effects. A primary goal of current research in drug discovery and development is to fully understand the interaction between transporters and drugs at both system level and individual level for personalized therapy. Pharmacogenomics studies the genetic basis of the individual variations in response to drug therapy, whereas systems biology provides the understanding of biological processes at the system level. The integration of pharmacogenomics with systems biology in membrane transporter study is necessary to solve complex problems in diseases and drug effects. Such integration provides insight to key issues of pharmacogenomics and systems biology of membrane transporters. These key issues include the correlations between structure and function, genotype and phenotype, and systematic interactions between different transporters, between transporters and other proteins, and between transporters and drugs. The exploration in these key issues may ultimately contribute to the personalized medicine with high efficacy but less toxicity, which is the overall goal of pharmacogenomics and systems biology.     

Role of neuroproteomics in CNS drug discovery

Neuroproteomics is the application of proteomics to the study of the CNS and its disorders. Proteomic technologies can be applied to the discovery of targets for drugs to treat neurological disorders. Diseases that are particularly suitable for this approach are those with protein pathology, such as Alzheimer's disease. Important receptors for CNS drugs include proteins such as G-protein-coupled receptors, N-methyl-d-aspartate receptors and protein kinases. Molecular diagnostics can be based on proteins detected in the cerebrospinal fluid and these same proteins can serve as drug targets. Proteomics complements pharmacogenomics and will facilitate the development of personalized medicines for neurological disorders.     

常用口服降糖药的药物基因组学研究进展

近年来,中国 2 型糖尿病(T2DM)发病率呈快速增长趋势。T2DM 是一种慢性代谢性疾病,涉及全身各个系统,甚至可能引起严 重的并发症。大多数 T2DM 患者需长期口服降糖药物。口服降糖药的药物基因组学研究可指导个体化治疗,改善疗效,降低用药成本,减 少不良反应和并发症风险,已成为当前研究的热点。综述常用口服降糖药药效学和药代动力学参数的相关基因多态性研究进展,为更加合理、 有效地进行糖尿病临床个体化治疗提供参考。     

Pharmacogenomics in colorectal carcinomas: future perspectives in personalized therapy

The recent introduction of new drugs such as capecitabine, irinotecan, and oxaliplatinum has greatly improved the clinical outcome of patients with advanced/metastatic colorectal cancer. Nevertheless, some patients may suffer from the adverse drug reactions which will probably be the main cause of chemotherapy failure. The goal of pharmacogenomics is to find correlations between therapeutic responses to drugs and the genetic profiles of patients; the different responses to a particular drug are due, in fact, not only to the specific clinico-pathological features of the patient or to environmental factors, but also to the ethnic origins and the particular individual's genetic profile. Genes which codify for the metabolism enzymes, receptor proteins, or protein targets of chemotherapy agents often present various genetic polymorphisms. The main aim of this review is to provide an overview of the known polymorphisms present in the genes which codify for factors (thymidylate synthase dihydropyrimidine dehydrogenase, uridine diphosphate (UDP)-glucuronosyl-transferase 1A1, enzymes implicated in DNA repair) involved in the action mechanisms of the drugs now utilized in chemotherapeutic treatment of colorectal carcinoma, such as fluoropyrimidines, irinotecan, and platinum agents.     

Adverse reactions to drugs in general practice.

Of 817 patients in a general-practice survey of adverse reactions to drugs, 41% were thought to have "certainly" or "probably" had a reaction to the drug prescribed. Adverse effects on the gastrointestinal and central nervous systems were the most frequently reported, and 90% of reactions had occurred by the fourth day of treatment. More patients given drugs acting on the central nervous system and antihistamines reported reactions than those in other categories. A higher incidence of adverse drug effects is shown in this general-practice survey than in other, mainly hospital-based, surveys. Further intensive surveillance for adverse effects of drugs is recommended to provide additional information on the burden of drug-induced disease in the community.     

风湿病治疗药物的药物基因组学研究及进展

风湿病的传统治疗以激素和甲氨蝶呤为代表的改善病情药物为主,随着分子水平研究的深入,以肿瘤坏死因子α阻断剂为代表的多种靶向生物制剂进入临床。药物的选择性治疗必须依靠基因组及药物遗传学的研究,对不同患者疗效及药物毒副反应作个体化的分析,从而正确的选择药物。本文就风湿病的传统的甲氨蝶呤和TNF-α阻断剂在药物基因组学预测药物的疗效及副作用等进行综述。     

How good are articles on adverse drug reactions?

A study was carried out of the quality and completeness of articles on adverse drug reactions: 5737 articles from 80 countries published between 1972 and 1979 were studied. Only 61% of the articles included information on the number of patients treated and the number with adverse drug reactions, yet these are essential for calculating the incidence of adverse reactions. In only 55% could the incidence of a particular adverse reaction be calculated. Great importance is placed on articles on adverse reactions, particularly those that report on many patients. Authors and editors should ensure that articles include the following information: drug regimens, numbers of patients treated, numbers of patients developing adverse reactions, and nature and incidence of adverse reactions.     

Predisposing Factors in Adverse Reactions to Drugs

Predisposing factors were sought in 118 patients who developed adverse drug reactions in hospital. Significantly more patients of 60 years and over, and more women than men, developed adverse drug reactions. Patients with reactions had more drugs before the development of the reaction than patients who did not develop reactions. A previous adverse drug reaction and a history of allergic disease were significant factors, while a history of jaundice or the presence of diabetes mellitus and renal disease was not.     

Clinical Use of Pharmacogenomic Tests in 2009

Pharmacogenomics is a new field where testing an individual can define either a risk status for an adverse event, or the rate of metabolism of a drug. This is achieved by the categorisation of the enzyme activity or documenting genetic polymorphisms of a metabolising enzyme. The best example of risk status assessment is the recent finding that HLA-B typing a person can predict whether they are at risk of a severe skin reaction from the drug abacavir. Those patients showing HLA-B*5701, who are being considered for abacavir therapy, can be prevented from developing potentially toxic epidermal necrosis (TEN) or Stevens-Johnson Syndrome by avoiding abacavir. The evidence for HLA-B typing for allopurinol and carbamazepine has also been described. Most other pharmacogenomic tests are of drug metabolising enzymes, which can either be assessed using “probe” drugs and measuring a ratio of parent drug to metabolite, or, by genetic testing for polymorphisms of the genes. In practice, testing is usually done by molecular testing, but this typically does not detect all polymorphisms. This article briefly reviews the evidence for the utilisation of pharmacogenomics for antidepressant drugs, tamoxifen, codeine, warfarin, azathioprine, clopidogrel, omeprazole, tacrolimus and irinotecan. There are few pharmacogenomics tests being carried out in practice, as there has not been a wide appreciation of their use, and only limited evidence exists for many individual drugs. It is expected that utilisation will increase as more evidence becomes available and there is a wider understanding of the existing evidence by the medical profession.     

Deciphering next-generation pharmacogenomics: an information technology perspective

In the post-genomic era, the rapid evolution of high-throughput genotyping technologies and the increased pace of production of genetic research data are continually prompting the development of appropriate informatics tools, systems and databases as we attempt to cope with the flood of incoming genetic information. Alongside new technologies that serve to enhance data connectivity, emerging information systems should contribute to the creation of a powerful knowledge environment for genotype-to-phenotype information in the context of translational medicine. In the area of pharmacogenomics and personalized medicine, it has become evident that database applications providing important information on the occurrence and consequences of gene variants involved in pharmacokinetics, pharmacodynamics, drug efficacy and drug toxicity will become an integral tool for researchers and medical practitioners alike. At the same time, two fundamental issues are inextricably linked to current developments, namely data sharing and data protection. Here, we discuss high-throughput and next-generation sequencing technology and its impact on pharmacogenomics research. In addition, we present advances and challenges in the field of pharmacogenomics information systems which have in turn triggered the development of an integrated electronic ‘pharmacogenomics assistant’. The system is designed to provide personalized drug recommendations based on linked genotype-to-phenotype pharmacogenomics data, as well as to support biomedical researchers in the identification of pharmacogenomics-related gene variants. The provisioned services are tuned in the framework of a single-access pharmacogenomics portal.     

New advances in pharmacogenomics

In the years to come, pharmacogenomics will make an impact on the development of new drugs. Numerous publications have shown that gene polymorphism can influence drug toxicity and/or efficacy. In order to improve current applications of pharmacogenomics, some technical limitations regarding marker generation, genotyping and biostatistical analysis are being overcome.     

Recognizing and reporting adverse drug reactions.

Although physicians in practice are most likely to see patients with adverse drug reactions, they may fail to recognize an adverse effect or to attribute it to a drug effect and, when recognized, they may fail to report serious reactions to the US Food and Drug Administration (FDA). To recognize and attribute an adverse event to a drug effect, physicians should review the patient''s clinical course, looking at patient risk factors, the known adverse reactions to the suspected drug, and the likelihood of a causal relationship between the drug and the adverse event-based on the temporal relationship, response to stopping or restarting the drug, and whether other factors could explain the reaction. Once an adverse drug reaction has been identified, the patient should be informed and appropriate documentation made in the patient''s medical record. Serious known reactions and all reactions to newly released drugs or those not previously known to occur (even if the certainty is low) should be reported to the FDA.     

海洋药物藻酸双酯钠研究进展及启示

通过总结我国自主研发的第一个海洋药物藻酸双酯钠（propylene glycol alginate sodium sulfate,PSS）近30年的生产和临床应用情况,对其生产工艺和质量标准、药理活性、临床用药和不良反应等进行系统深入的探讨,阐明PSS的构效关系和作用机制,以期进行PSS产品的更新换代,提高市场竞争力,扩大PSS临床新的适应症等,从而实现对PSS的技术改造和升级,进一步为广大患者提供更加安全有效的海洋药物,为海洋多糖类药物的研究与开发提供参考。     

Impact of pharmacogenomics on clinical practice in oncology

Multiple drug strategies for many cancer types are now readily available and there is a clear need for tools to inform decision making on therapy selection. Although there is still a long way to go before pharmacogenomics achieves the goal of individualized selection of cancer treatment, promising progress is being made. Genetic testing for thiopurine methyltransferase (TPMT) variant alleles in patients prior to mercaptopurine administration, and for UGT1A1*28 in patients prior to administration of irinotecan therapy, along with the instigation of genotype-guided clinical trials (e.g. TYMS) are important advances in cancer pharmacogenomics. Markers for the toxicity and efficacy of many oncology drugs remain unknown; however, the examples highlighted here suggest progress is being made towards the incorporation of pharmacogenomics into clinical practice in oncology.     

Pharmacogenomics of osteoporosis: opportunities and challenges

The genetics of osteoporosis can be considered in two broad areas: disease susceptibility and drug activity. While the former has been studied, the latter is still largely untouched. Pharmacogenomics is the utilization of genetic information to predict outcome of drug treatment, with respect to both beneficial and adverse effects. The pharmacotherapy of osteoporosis is characterized by variability in therapeutic response with limited prediction of response on a patient-by-patient basis. This is particularly problematic in a clinical situation where therapy is typically required for several years before outcomes can be evaluated for an individual. Thus, the emerging field of pharmacogenomics holds great potential for refining and optimising pharmacological treatment of osteoporosis. Key components for future development of the pharmacogenomics of osteoporosis should include improved understanding of mechanisms of drug action, identification of candidate genes and their variants and expansion of clinical trials to include genetic profiling. This approach could provide clinicians and scientists with powerful tools to dissect novel molecular pathways involved in osteoporosis and to identify new drug targets. The iterative combination of innovative genomics with classical endocrinological approaches in osteoporosis research can be examined as a model of biological research and innovate therapeutical approaches in a continuing interaction between clinical science and basic research.     

Admissions to Hospital due to Drugs

In a survey of adverse drug reactions in wards of two Belfast hospitals for 52 weeks in 1965–6, 2·9% of 1,268 patients seen were admitted to hospital because of adverse reactions to drugs taken for therapeutic reasons and 2·1% were admitted because of self-poisoning. Patients admitted because of adverse drug reactions were older than those admitted because of self-poisoning and stayed in hospital longer. Among the drugs which caused the adverse reactions were digitalis preparations, antibiotics, corticosteroids, anticoagulants, analgesics, and tranquillizers. Hypersensitivity and side-effect types of reactions were the most common. Barbiturates were the most frequently used drugs in suicidal attempts.     

Intensive Hospital Monitoring of Adverse Reactions to Drugs

A total of 1,268 patients admitted to hospital wards were kept under surveillance by one observer throughout their stay in hospital. All drugs given to them and the occurrence of adverse reactions were recorded.Drug reactions were found in 10·2% of the 1,160 patients who received drug therapy. Most reactions were due to known pharmacological actions of the drugs. Though only four reactions were of life-threatening seriousness, 80% of the 129 reactions observed were of moderate severity. Digitalis preparations, bronchodilator drugs, and ampicillin had the highest reaction rates. It is suggested that larger surveys of adverse reactions in relation to drug usage would make a useful contribution to the problem.     

Physicians and the pharmaceutical industry: a dysfunctional relationship

The pharmaceutical industry is one of the largest and most profitable industries in the world, and in the United States, the industry has a particularly privileged economic position. Yet the cost of drugs in the United States is higher than anywhere else, due largely to the fact that the industry is focusing increasingly on marketing rather than on the development of meaningful new medications: available evidence does not support claims of great expense for the development of new drugs. Because of its vast resources, the pharmaceutical industry has assumed an increasing influence in medicine, which, given the differences in values and priorities between medicine and the drug companies, is a cause for concern. The pharmaceutical industry has acted to maximize its profits in ways that frequently conflict with medicine's need for truth and full disclosure. Indeed, the industry has arguably worked to compromise physicians' judgments, as well as academic standards. As a result, despite government regulation there have been unnecessary adverse effects from drugs. The experience with butorphanol (Stadol) exemplifies problems in the current system and the harm that can result. Changes are suggested to make the pharmaceutical industry more responsive to the needs of patients and physicians.     

Adverse hepatic drug reactions: inflammatory episodes as consequence and contributor

Susceptibility to drug toxicity is influenced by a variety of factors, both genetic and environmental. The focus of this article is the evidence addressing the hypothesis that inflammation is both a result of and a susceptibility factor for drug toxicity, with an emphasis on liver as a target organ. Results of studies suggesting a role for inflammatory mediators in the hepatotoxicity caused by acetaminophen or ethanol are discussed. For several drugs, the evidence from animal models that concurrent inflammation increases injury is presented. In addition, the occurrence of adverse drug reactions in people with preexisting inflammatory diseases is considered. The special case of idiosyncratic drug reactions is discussed and the potential raised for development of animal models for this type of drug toxicity. The conclusion is that inflammatory factors should be considered as determinants of sensitivity to adverse drug reactions.