Pharmacogenomics in cancer treatment defining genetic bases for inter-individual differences in responses to chemotherapy

Hyaluronic acid-modified liposomal honokiol nanocarrier: Enhance anti-metastasis and antitumor efficacy against breast cancer

In an effort to enhance antitumor and anti-metastasis of breast cancer, honokiol (HNK) was encapsulated into hyaluronic acid (HA) modified cationic liposomes (Lip). The prepared HA-Lip-HNK had a spherical shape with a narrow size distribution. The enhanced antitumor efficacy of HA-Lip-HNK was investigated in 4T1 cells in vitro, wherein flow cytometry and confocal microscopy analysis revealed its HA/CD44-mediated greater cellular internalization. As anticipate, the significant cytotoxicity of the HA-Lip-HNK was also observed in 4T1 tumor spheroids. Furthermore, the superior prevention of tumor metastasis by HA-Lip-HNK was verified by in vitro anti-invasion, wound healing and anti-migration assessments, and in vivo bioluminescence imaging in pulmonary metastasis model. Finally, compared with unmodified liposomes, the HA-Lip-HNK exhibited higher tumor accumulation, and achieved a tumor growth inhibition rate of 59.5 %. As a result, the HA-Lip-HNK may serve as a promising tumor-targeted drug delivery strategy for the efficient therapy of metastatic breast cancer.

Efficacy of olanzapine in symptom relief and quality of life in gastric cancer patients receiving chemotherapy

Background:

Considering the incidence and prevalence rates of gastric cancer in Mazandaran Province of Iran, this research was performed to evaluate the efficacy and safety of olanzapine in symptom relief and quality of life (QOL) improvement of gastric patients receiving chemotherapy.

Materials and Methods:

This clinical trial was conducted on thirty new cases of gastric cancer patients whose treatment protocol was planned on chemotherapy and were allocated into two groups by simple random sampling. Intervention group (15 patients) received olanzapine tablets (2.5–10 mg/day) a day before the beginning of chemotherapy; in the 1^st day of chemotherapy to 8 weeks after chemotherapy, besides the routine treatment regimens. The control group received only the routine treatment regimens. The patients were followed for 8 weeks after intervention. All of the patients were assessed with Hospital Anxiety and Depression Scale (HADS) and WHO-QOL-BREF questionnaires; further, Rhodes index was used to evaluate nausea and vomiting (N/V) status.

Results:

All the recruited patients continued the allocated interventions (no lost to follow-up). N/V decreased in the case group, but the difference was not statistically significant (P = 0.438). The patients' appetite and body mass index increased (P = 0.006). Anxiety and depression subscales of HADS had significant differences between the two groups (P < 0.001) in the 4^th and 8^th week after treatment. Among the different subdomains of QOL, only physical health improved significantly after intervention (P < 0.05), but no significant difference was observed in other subdomains and also total QOL score (P > 0.05). No significant increase was observed in fasting and 2-h postprandial blood glucose and lipid profile (P > 0.05).

Conclusion:

Olanzapine can be considered as an effective drug to increase appetite and decrease anxiety and depression in patients with gastric cancer.

Gene polymorphisms in the folate metabolism and their association with MTX-related adverse events in the treatment of ALL

The antifolate drug methotrexate (MTX) is widely used in the treatment of various neoplastic diseases, including acute lymphoblastic leukemia (ALL). MTX significantly increases cure rates and improves patients' prognosis. Despite that it achieved remarkable clinical success, a large number of patients still suffer from treatment toxicities or side effects. Even to this date, chemotherapeutic regiments have not been personalized because of interindividual differences that affect MTX response, especially polymorphisms in key genes. The pharmacological pathway of MTX in cells is useful to identify gene polymorphisms that influence the process of treatment. The aim of this review was to discuss the gene polymorphisms of drug-metabolizing enzymes in the MTX pathway and their toxicities on ALL treatment.

Application of oncoproteomics to aberrant signalling networks in changing the treatment paradigm in acute lymphoblastic leukaemia

Oncoproteomics is an important innovation in the early diagnosis, management and development of personalized treatment of acute lymphoblastic leukaemia (ALL). As inherent factors are not completely known - e.g. age or family history, radiation exposure, benzene chemical exposure, certain viral exposures such as infection with the human T-cell lymphoma/leukaemia virus-1, as well as some inherited syndromes may raise the risk of ALL - each ALL patient may modify the susceptibility of therapy. Indeed, we consider these unknown inherent factors could be explained via coupling cytogenetics plus proteomics, especially when proteins are the ones which play function within cells. Innovative proteomics to ALL therapy may help to understand the mechanism of drug resistance and toxicities, which in turn will provide some leads to improve ALL management. Most important of these are shotgun proteomic strategies to unravel ALL aberrant signalling networks. Some shotgun proteomic innovations and bioinformatic tools for ALL therapies will be discussed. As network proteins are distinctive characteristics for ALL patients, unrevealed by cytogenetics, those network proteins are currently an important source of novel therapeutic targets that emerge from shotgun proteomics. Indeed, ALL evolution can be studied for each individual patient via oncoproteomics.

Role of NOS3 DNA variants in externalizing behavioral problems observed in childhood leukemia survivors

OBJECTIVE

Neuropsychological problems occurrence varies among childhood cancer survivors, and associated risk factors have not been fully deciphered. We wanted to study the role of genetic variants in behavioral problems in this population.

STUDY DESIGN

Behavioral problems in pediatric acute lymphoblastic leukemia patients (n=138) were investigated longitudinally, using the Child Behavior Checklist questionnaire and multilevel statistical modeling. Thirty-four candidate polymorphisms, related to anticancer drug effects, were investigated.

RESULTS

NOS3 gene functional polymorphisms showed significant association: patients homozygous for the minor allele at investigated loci showed decreased externalizing behavioral problems scores over time (t tests: T-786C n=69, P=0.003; G894T n=71, P=0.065). The effect was even more pronounced for individuals that are homozygous for the -786C844T haplotype (t test, n=69, P<0.001) and results were supported by multilevel modeling analyses (P<0.001). No such association was observed for internalizing behavioral problems.

CONCLUSION

NOS3 variants modulate externalizing problems individual trajectories, likely in relationship with glucocorticoid exposure.

Cancer pharmacogenomics in children: research initiatives and progress to date

Over the last few decades, cure rates for pediatric cancer have increased dramatically, and now over 80 % of children with cancer are cured of their disease. This improvement in cure has come with a significant cost, with many children suffering irreversible, life-threatening, or long-lasting toxicities due to the medications required during their treatment. In the last 2 decades, major technological advances in genomics and the mapping of the human genome have made it possible to identify genetic differences between children in order to investigate differing responses to cancer therapy and to help explain why children treated with the same medications can have different outcomes. The emerging field of pharmacogenomics has had many important findings in pediatric cancer. The focus of this review is drug toxicity in pediatric cancer and the use of pharmacogenomics to reduce these adverse drug reactions, with a specific focus on thiopurines, methotrexate, cisplatin, vincristine and anthracyclines. Future areas of research and the need for international collaboration are discussed.

Psychiatric pharmacogenomics in pediatric psychopharmacology

This article provides an overview of where psychiatric pharmacogenomic testing stands as an emerging clinical tool in modern psychotropic prescribing practice, specifically in the pediatric population. This practical discussion is organized around the state of psychiatric pharmacogenomics research when choosing psychopharmacologic interventions in the most commonly encountered mental illnesses in youth. As with the rest of the topics on psychopharmacology for children and adolescents in this publication, a clinical vignette is presented, this one highlighting a clinical case of a 16 year old genotyped during hospitalization for recalcitrant depression.

Prognostic significance of biochemical markers in African Burkitt's lymphoma

BACKGROUND AND PURPOSE Endemic Burkitt's lymphoma (eBL) remains the prevalent form of paediatric cancer in tropical Africa with subtle pathological differences. This calls for intensified efforts to validate the global prognostic markers within local settings for improved cancer treatment and survival. This study proposes prognostic markers for enhanced eBL treatment and management. PATIENTS AND METHOD One hundred and eighty histologically and/or clinically diagnosed BL patients at Komfo Anokye Teaching Hospital, Kumasi, Ghana were eligible for this cross-sectional eight-year retrospective study. Biochemical, clinical and demographic data, before chemotherapy administration, were documented and examined for their progression-free (PFS) and overall survival (OS) significance. RESULTS A mean age of 6 (SD=2.7, range: 1-16) years was observed with general male dominance (M:F=1.69:1). Total serum lactate dehydrogenase (HR=2.04; 95% CI, 1.25-3.32; log rank=8.3; p=0.004), serum creatinine (HR=3.59; 95% CI, 1.62-7.98; log rank=15.4; p=0.002) and St. Jude stage (HR=1.74; 95% CI, 1.11-2.73; log rank=8.0; p=0.015) were important independent prognostic biochemical markers for both PFS and OS. Age, serum calcium, uric acid, potassium, sodium and phosphorus were non-prognostic. CONCLUSION The better monitoring of these prognostic indices coupled with risk-stratification treatment may improve patients' survival, especially in resource-limited settings.

Challenges in implementing individualized medicine illustrated by antimetabolite therapy of childhood acute lymphoblastic leukemia

Predicting the response to medical therapy and subsequently individualizing the treatment to increase efficacy or reduce toxicity has been a longstanding clinical goal. Not least within oncology, where many patients fail to be cured, and others are treated to or beyond the limit of acceptable toxicity, an individualized therapeutic approach is indicated. The mapping of the human genome and technological developments in DNA sequencing, gene expression profiling, and proteomics have raised the expectations for implementing genotype-phenotype data into the clinical decision process, but also multiplied the complex interaction of genetic and other laboratory parameters that can be used for therapy adjustments. Thus, with the advances in the laboratory techniques, post laboratory issues have become major obstacles for treatment individualization. Many of these challenges have been illustrated by studies involving childhood acute lymphoblastic leukemia (ALL), where each patient may receive up to 13 different anticancer agents over a period of 2-3 years. The challenges include i) addressing important, but low-frequency outcomes, ii) difficulties in interpreting the impact of single drug or single gene response data that often vary across treatment protocols, iii) combining disease and host genomics with outcome variations, and iv) physicians' reluctance in implementing potentially useful genotype and phenotype data into clinical practice, since unjustified downward or upward dose adjustments could increase the of risk of relapse or life-threatening complications. In this review we use childhood ALL therapy as a model and discuss these issues, and how they may be addressed.

Germline genetic variation in an organic anion transporter polypeptide associated with methotrexate pharmacokinetics and clinical effects

PURPOSE

Methotrexate plasma concentration is related to its clinical effects. Our aim was to identify the genetic basis of interindividual variability in methotrexate pharmacokinetics in children with newly diagnosed acute lymphoblastic leukemia (ALL).

PATIENTS AND METHODS

We performed a genome-wide analysis of 500,568 germline single-nucleotide polymorphisms (SNPs) to identify how inheritance affects methotrexate plasma disposition among 434 children with ALL who received 3,014 courses of methotrexate at 2 to 5 g/m(2). SNPs were validated in an independent cohort of 206 patients.

RESULTS

Adjusting for age, race, sex, and methotrexate regimen, the most significant associations were with SNPs in the organic anion transporter polypeptide, SLCO1B1. Two SNPs in SLCO1B1, rs11045879 (P = 1.7 x 10(-10)) and rs4149081 (P = 1.7 x 10(-9)), were in linkage disequilibrium (LD) with each other (r(2) = 1) and with a functional polymorphism in SLCO1B1, T521C (rs4149056; r(2) > 0.84). rs11045879 and rs4149081 were validated in an independent cohort of 206 patients (P = .018 and P = .017), as were other SLCO1B1 SNPs residing in different LD blocks. SNPs in SLCO1B1 were also associated with GI toxicity (odds ratio, 15.3 to 16.4; P = .03 to .004).

CONCLUSION

A genome-wide interrogation identified inherited variations in a plausible, yet heretofore low-priority candidate gene, SLCO1B1, as important determinants of methotrexate's pharmacokinetics and clinical effects.

Polymorphisms in multidrug resistance-associated protein gene 4 is associated with outcome in childhood acute lymphoblastic leukemia

Methotrexate and 6-mercaptopurine, important components of acute lymphoblastic leukemia treatment, are substrates for multidrug resistance-associated protein MRP4. Eight single nucleotide polymorphisms were analyzed in MRP4 gene, and 4 variants were identified as tagSNPs with frequency more than or equal to 5%. They were investigated for association with treatment responses in 275 children with acute lymphoblastic leukemia. The TC genotype of the regulatory T-1393C polymorphism was associated with better event-free survival (P = .02) and lower methotrexate plasma levels (P = .01). The CA genotype of A934C (Lys304Asn) substitution correlated in contrast with lower event-free survival (P = .02) and higher frequency of high-grade thrombocytopenia (P = .01). Gene reporter assay showed that the promoter haplotype uniquely tagged by the C-1393 allele conferred higher promoter activity compared with remaining haplotypes (P < .001). Further analyses are needed to replicate this pilot study and get closer insight into the functional effect of these polymorphisms.

Novel multistranded, alternative, plasmid and helical transitional DNA and RNA microarrays: implications for therapeutics

Novel multistranded and alternative DNA, RNA and plasmid microarrays (transitional structural nucleic acid microarrays) have been developed that allows for the immobilization of intact, nondenatured, double-stranded DNA, double-stranded RNA, and alternative and multistranded nucleic acids. It also allows for the study of transitional changes that occur in the structure of DNA and RNA. Alternative types of DNA, RNA and multistranded nucleic acids are immobilized by a variety of different surface chemistries (i.e., noncovalent or covalent) onto a novel substrate surface. This technology represents the next generation of microarrays, which will aid in the characterization of nucleic acid structure and function, and accelerate the discovery of drugs that bind to nucleic acids. In addition, we demonstrate four novel techniques that are the first practical applications of the microarray, that is, transitional structural chemogenomics, transitional structural chemoproteomics, transitional structural pharmacogenomics and transitional structural pharmacoproteomics. These novel nucleic acid microarrays, together with pharmacogenomics, can be used to improve the study of DNA and RNA structure, gene expression, drug development and treatment of various diseases.

Implementation of pharmacogenomics into the clinical practice of therapeutics: issues for the clinician and the laboratorian

Pharmacogenomics promises to improve therapeutic care by providing the right drug and dosage to the appropriate patient. Despite widespread interest in personalized medicine, the implementation of clinical pharmacogenomics has been slow. The major issue for clinicians is the lack of evidence that pharmacogenomic testing improves clinical outcomes and that testing is cost-effective. Only a few randomized clinical trials comparing pharmacogenomic testing with standard protocols have been conducted. The few studies that are available have either been underpowered or demonstrated only modest benefits. Nevertheless, if clinical decisions are made regarding therapeutic selection and dosing, pharmacogenomic testing may be justified. Issues for the clinical laboratories (who are responsible for providing pharmacogenomic services) to consider, include the availability of US FDA-cleared tests, the absence of reimbursement codes, the need for genotyping accuracy and the need to find clinical expertise to interpret laboratory results. From the clinical laboratory perspective, testing can be better implemented when these barriers are resolved or minimized. Clinical pharmacogenomics also offers a new field for translational research and teaching at various levels.

Pharmacogenetics influence treatment efficacy in childhood acute lymphoblastic leukemia

Pharmacogenetics covers the genetic variation affecting pharmacokinetics and pharmacodynamics, and their influence on drug-response phenotypes. The genetic variation includes an estimated 15 million single nucleotide polymorphisms (SNPs) and is a key determinator for the interindividual differences in treatment resistance and toxic side effects. As most childhood acute lymphoblastic leukemia treatment protocols include up to 13 different chemotherapeutic agents, the impact of individual SNPs has been difficult to evaluate. So far focus has mainly been on the widely used glucocorticosteroids, methotrexate, and thiopurines, or on metabolic pathways and transport mechanisms that are common to several drugs, such as the glutathione S-transferases. However, beyond the thiopurine methyltransferase polymorphisms, the candidate-gene approach has not established clear associations between polymorphisms and treatment response. In the future, high-throughput, low-cost, genetic platforms will allow screening of hundreds or thousands of targeted SNPs to give a combined gene-dosage effect (=individual SNP risk profile), which may allow pharmacogenetic-based individualization of treatment.

The integration of personalized and systems medicine: bioinformatics support for pharmacogenomics and drug discovery

Pharmacogenomics may have a deep impact on every drug treatment protocol to bring the right drug to the right patient. While pharmacogenomics can help achieve individualized medicine, the study of systems biology can help us understand the key issues in pharmacogenomics at different levels. These key issues include the associations between structure and function, the correlations between genotype and phenotype, and the interactions among gene, drug, and environment. Utilizing bioinformatics in pharmacogenomics that is conducted in a systemic way can help integrate information from different levels. At the molecular level, the detailed features of a gene and the relationship between genetic structure and function need to be explored. These detailed features include sequence analytic information such as sequence retrieval and structural modeling, sequence variation information, and sequence patterns that can correlate sequence structure to functional motifs. At the cellular level, the interactions and networks among those molecules should be examined. Higher degrees of understanding at the tissue and organism levels can help establish the correlations between genotype and phenotype. The application of bioinformatics methods in pharmacogenomics and systems biology should enable a more profound understanding of diseases at different levels and lead to both individualized and systems medicine. To facilitate up-to-date bio-informatics support, an integrated search engine and updated collections of tools are freely available at http://sysmed.pharmtao.com.

SNPs in disease gene mapping, medicinal drug development and evolution

Single nucleotide polymorphism (SNP) technologies can be used to identify disease-causing genes in humans and to understand the inter-individual variation in drug response. These areas of research have major medical benefits. By establishing an association between the genetic make-up of an individual and drug response it may be possible to develop a genome-based diet and medicines that are more effective and safer for each individual. Additionally, SNPs can be used to understand the molecular mechanisms of sequence evolution. It has been found that throughout the given gene, the rate, type and site of nucleotide substitutions as well as the selection pressure on codons is not uniform. The residues that evolve under strong selective pressures are found to be significantly associated with human disease. Deleterious mutations that affect biological function of proteins are effectively being rejected by natural selection from the gene pool. If substituted nucleotides are fixed during evolution then they may have selection advantages, they may be neutral, or they may be deleterious and cause pathology. Therefore, it is possible that disease-associated SNPs (or pathology) and evolution can be related to one another.

Pharmacogenetics and paediatric drug development: issues and consequences to labelling and dosing recommendations

The area of pharmacogenetics (PGt) is evolving rapidly. However, ongoing efforts in this field are not aligned with the requirements for the inclusion of clinically relevant findings into the label, especially with reference to paediatric indications. Clinical research in children poses unique issues from a practical and technical perspective, but many challenges can be overcome by applying advanced study design and data analysis methods. When investigating the role of PGt factors on treatment effect, all features that influence drug response must be taken into account. Yet, PGt often has a privileged status in research protocols, with PGt factors evaluated independently from other determinants of response, instead of being regarded as other demographic or clinical covariates (e.g., age, renal function). At present, guidelines to incorporate PGt findings into label statements are lacking in part because this is a new and incompletely understood area. This situation is no longer acceptable. To achieve the potential that PGt can offer to drug development and ultimately to drug prescription, academia, industry and regulatory agencies need to pool resources on the revision of study design and data analysis requisites, bringing in model-based methodologies to enable accurate interpretation of results and provide appropriate labelling recommendations.

Maximizing resilience through diverse levels of inquiry: Prevailing paradigms, possibilities, and priorities for the future

The study of resilience has two core characteristics: it is fundamentally applied in nature, seeking to use scientific knowledge to maximize well-being among those at risk, and it draws on expertise from diverse scientific disciplines. Recent advances in biological processes have confirmed the profound deleterious effects of harsh caregiving environments, thereby underscoring the importance of early interventions. What remains to be established at this time is the degree to which insights on particular biological processes (e.g., involving specific brain regions, genes, or hormones) will be applied in the near future to achieve substantial reductions in mental health disparities. Aside from biology, resilience developmental researchers would do well to draw upon relevant evidence from other behavioral sciences as well, notably anthropology as well as family, counseling, and social psychology. Scientists working with adults and with children must remain vigilant to the advances and missteps in each others' work, always ensuring caution in conveying messages about the "innateness" of resilience or its prevalence across different subgroups. Our future research agenda must prioritize reducing abuse and neglect in close relationships; deriving the "critical ingredients" in effective interventions and going to scale with these; working collaboratively to refine theory on the construct; and responsibly, proactively disseminating what we have learned about the nature, limits, and antecedents of resilient adaptation across diverse at-risk groups.