Association of the Trough, Peak/Trough Ratio of Imatinib, Pyridine-N-Oxide Imatinib and ABCG2 SNPs 34 G>A and SLCO1B3 334 T>G With Imatinib Response in Egyptian Chronic Myeloid Leukemia Patients

The interplay of knowledge, motivation, and treatment response in medication adherence among patients with chronic myeloid leukemia treated with Imatinib

Chronic Myeloid Leukemia (CML) requires consistent medication adherence to Imatinib (IM) for optimal outcomes, however, adherence to oral chemotherapy is challenging. This observational study explores the relationship between patient knowledge, motivation, and adherence to IM therapy, and their collective impact on clinical outcomes. A prospective, observational study was conducted with 101 CML patients. The 6-Item Morisky Medication Adherence Scale (MMAS-6) was used to assess adherence, motivation, and knowledge levels. The study found that high motivation was significantly associated with lower BCR-ABL expression (p = 0.025). Patients with high knowledge and motivation had a 71% favorable response rate, compared to 0% in those with low knowledge and motivation (p = 0.01). As conclusion both patient motivation and knowledge are crucial for favorable treatment outcomes in CML. High levels of both significantly correlate with better clinical responses. Tailored interventions to enhance patient knowledge and motivation are essential.

From Drug Discovery to Drug Approval: A Comprehensive Review of the Pharmacogenomics Status Quo with a Special Focus on Egypt

Pharmacogenomics (PGx) is the hope for the full optimization of drug therapy while minimizing the accompanying adverse drug events that cost billions of dollars annually. Since years before the century, it has been known that inter-individual variations contribute to differences in specific drug responses. It is the bridge to what is well-known today as "personalized medicine". Addressing the drug's pharmacokinetics and pharmacodynamics is one of the features of this science, owing to patient characteristics that vary on so many occasions. Mainly in the liver parenchymal cells, intricate interactions between the drug molecules and enzymes family of so-called "Cytochrome P450" occur which hugely affects how the body will react to the drug in terms of metabolism, efficacy, and safety. Single nucleotide polymorphisms, once validated for a transparent and credible clinical utility, can be used to guide and ensure the succession of the pharmacotherapy plan. Novel tools of pharmacoeconomics science are utilized extensively to assess cost-effective pharmacogenes preceding the translation to the bedside. Drug development and discovery incorporate a drug-gene perspective and save more resources. Regulations and laws shaping the clinical PGx practice can be misconceived; however, these pre-/post approval processes ensure the product's safety and efficacy. National and international regulatory agencies seek guidance on maintaining conduct in PGx practice. In this patient-centric era, social and legal considerations manifest in a way that makes them unavoidable, involving patients and other stakeholders in a deliberate journey toward utmost patient well-being. In this comprehensive review, we contemporarily addressed the scientific leaps in PGx, along with various challenges that face the proper implementation of personalized medicine in Egypt. These informative insights were drawn to serve what the Egyptian population, in particular, would benefit from in terms of knowledge and know-how while maintaining the latest global trends. Moreover, this review is the first to discuss various modalities and challenges faced in Egypt regarding PGx, which we believe could be used as a pilot piece of literature for future studies locally, regionally, and internationally.

Imatinib pharmacokinetics and creatine kinase levels in chronic myeloid leukemia patients: implications for therapeutic response and monitoring

BACKGROUND

Imatinib treatment for certain cancers can lead to elevated creatine kinase (CK) levels, potentially indicating muscle injury, and ongoing research aims to understand the correlation between imatinib levels and creatine kinase to assess its impact on treatment response.

METHODS

This single-center observational study involved 76 chronic myeloid leukemia (CML) patients receiving imatinib treatment, focusing on evaluating drug and metabolite levels using liquid chromatography-mass spectrometry (LC-MS-MS) instrumentation. Serum CK and creatine kinase-MB (CK-MB) levels were assessed using Colorimetric kits.

RESULTS

CK and CK-MB levels were measured, CK showed a median value of 211.5 IU/l and CK-MB showed a median value of 4.4 IU/l. Comparing low and high CK groups, significant differences were found in peak and trough plasma concentrations of imatinib and its metabolites. Correlations between CK levels and pharmacokinetic parameters were explored, with notable associations identified. Binary logistic regression revealed predictors influencing the therapeutic response to imatinib and categorized expected CK levels into high or low, with peak levels of imatinib emerging as a significant predictor for CK level categorization.

CONCLUSION

The study highlights the link between imatinib's pharmacokinetics and elevated CK levels, indicating a possible correlation between specific metabolites and improved treatment response. Individualized monitoring of CK levels and imatinib pharmacokinetics could enhance care for CML patients.

Contribution of genetic polymorphism in ABCB1 to individual variations of imatinib plasma levels in patients with gastrointestinal stromal tumor

Background

Imatinib mesylate (IM) is a first-line treatment option for the majority of patients diagnosed with gastrointestinal stromal tumors (GISTs). Although the clinical benefit is high, interindividual response is variable. This study thus aimed to assess how genetic polymorphisms can affect the blood levels of IM and treatment outcomes in patients with GIST.

Methods

A total of 31 single-nucleotide polymorphisms (SNPs) in selected cytochrome P450 (P450), ATP-binding cassette transporter (ABC), solute carrier family (SLC), interleukin-4 receptor (IL4R), and vascular endothelial growth factor (VEGF) genes were genotyped using an SNP mass array platform. A total of 192 consecutive patients with GIST who received 400 mg of IM daily were enrolled into the study, with 1,485 blood samples being analyzed. According to genotypes, IM trough concentrations were tested and compared. Progression-free survival (PFS) and overall survival (OS) were also assessed.

Results

With a mean follow-up of 75.99 months, trough concentrations of imatinib were examined at average time points of 7.73 for each patient. Polymorphism in ABCB1 rs1045642 was found to be associated with steady-state IM trough plasma levels (P=0.008). Patients with the C genotype (CT + CC) of rs1045642 exhibited higher IM trough concentrations (1,271.09±306.69 ng/mL) compared to those with the TT genotype (1,106.60±206.05 ng/mL). No statistically significant differences in IM plasma concentration were observed for the other SNPs tested. None of the tested SNPs displayed a significant association with patients' survival in this study.

Conclusions

This is the largest cohort study evaluating the associations of SNP and imatinib blood trough levels. The ABCB1 rs1045642 genetic polymorphism may exert an effect on the pharmacokinetics of imatinib. The presence of the C allele in ABCB1 rs1045642 is predictive of a higher plasma concentration of IM.

Therapeutic drug monitoring and pharmacogenetics to tune imatinib exposure in gastrointestinal stromal tumor patients: hurdles and perspectives for clinical implementation

Tweetable abstract Present evidence supports the use of intensified pharmacologic monitoring of #imatinib including #TherapeuticDrugMonitoring and #PGx to improve outcomes in patients with GI stromal tumor. Future studies need to address emerging questions to facilitate implementation in clinics.

Effects of ABCG2 C421A and ABCG2 G34A genetic polymorphisms on clinical outcome and response to imatinib mesylate, in Iranian chronic myeloid leukemia patients

Background

Chronic myeloid leukemia (CML) is a multifactorial clonal myeloid neoplasm that mainly arises from the Philadelphia chromosome. Even though imatinib mesylate (IM) is considered the gold standard for first-line treatment, a number of CML patients have shown IM resistance that can be influenced by many factors, including pharmacogenetic variability. The present study examined whether two common single nucleotide polymorphisms (SNPs) of ABCG2 (G34A and C421A) contribute to IM resistance and/or good responses.

Material and methods

A total of 72 CML patients were genotyped with high-resolution melting (HRM) and restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). We also determined the cytogenetic and hematological response, as evaluable factors for measuring response to imatinib.

Results

In the current study, we explored the relationship between the different variants of ABCG2 G34A and C421A and clinical response to imatinib among CML patients. There were no statistically significant differences between genotypes of C421A and G34A and allele frequencies among the resistant and responder groups, with response to IM (P > 0.05). Also, we found no statistically significant association between genotypes and cytogenetic and hematological responses.

Conclusion

This is the first study to investigate the association between genotypes of the G34A and C421A SNPs and the outcome of IM treatment in Iranian population. As a whole, genotyping of these SNPs is unhelpful in predicting IM response in CML patients.

Genetic Variants of ABC and SLC Transporter Genes and Chronic Myeloid Leukaemia: Impact on Susceptibility and Prognosis

Solute carrier (SLC) and ATP-binding cassette (ABC) transporters comprise a variety of proteins expressed on cell membranes responsible for intrusion or extrusion of substrates, respectively, including nutrients, xenobiotics, and chemotherapeutic agents. These transporters mediate the cellular disposition of tyrosine kinase inhibitors (TKIs), and their genetic variants could affect its function, potentially predisposing patients to chronic myeloid leukaemia (CML) and modulating treatment response. We explored the impact of genetic variability (single nucleotide variants—SNVs) of drug transporter genes (ABCB1, ABCG2, SLC22A1, and SLC22A5) on CML susceptibility, drug response, and BCR-ABL1 mutation status. We genotyped 10 SNVs by tetra-primers-AMRS-PCR in 198 CML patients and 404 controls, and assessed their role in CML susceptibility and prognosis. We identified five SNVs associated with CML predisposition, with some variants increasing disease risk, including TT genotype ABCB1 (rs1045642), and others showing a protective effect (GG genotype SLC22A5 rs274558). We also observed different haplotypes and genotypic profiles associated with CML predisposition. Relating to drug response impact, we found that CML patients with the CC genotype (rs2231142 ABCG2) had an increased risk of TKI resistance (six-fold). Additionally, CML patients carrying the CG genotype (rs683369 SLC22A1) presented a 4.54-fold higher risk of BCR-ABL1 mutations. Our results suggest that drug transporters’ SNVs might be involved in CML susceptibility and TKI response, and predict the risk of BCR-ABL1 mutations, highlighting the impact that SNVs could have in therapeutic selection.

The role of OATP1B1 and OATP1B3 transporter polymorphisms in drug disposition and response to anticancer drugs: a review of the recent literature

INTRODUCTION

Members of the solute carrier family of organic anion transporting polypeptides are responsible for the cellular uptake of a broad range of endogenous compounds and xenobiotics in multiple tissues. In particular, the polymorphic transporters OATP1B1 and OATP1B3 are highly expressed in the liver and have been identified as critical regulators of hepatic eliminaton. As these transporters are also expressed in cancer cells, the function alteration of these proteins have important consequences for an individual's susceptibility to certain drug-induced side effects, drug-drug interactions, and treatment efficacy.

AREAS COVERED

In this mini-review, we provide an update of this rapidly emerging field, with specific emphasis on the direct contribution of genetic variants in OATP1B1 and OATP1B3 to the transport of anticancer drugs, the role of these carriers in regulation of their disposition and toxicity profiles, and recent advances in attempts to integrate information on transport function in patients to derive individualized treatment strategies.

EXPERT OPINION

Based on currently available data, it appears imperative that different aspects of disease, physiology, and drugs of relevance should be evaluated along with an individual's genetic signature, and that tools such as biomarker levels can be implemented to achieve the most reliable prediction of clinically relevant pharmacodynamic endpoints.

Effect of l-carnitine on cardiotoxicity and apoptosis induced by imatinib through PDGF/ PPARγ /MAPK pathways

A tyrosine kinase inhibitor Imatinib (IM) is used in the treatment of different varieties of cancers. The current study was designed to explore the beneficial role of l-carnitine against IM-induced cardiotoxicity in rats. Male albino rats received IM (40 mg/kg, i.p.) either alone or/in combination with l-carnitine (100 mg/kg, i.p.) for 7 days. IM increased serum inflammatory cytokines, concomitant with activation of cardiac MAPK, α-SMA, malondialdehyde (MDA) and nitric oxide(NO), decreased cardiac peroxisome proliferator-activated receptor-γ (PPAR-γ) level, superoxide dismutase (SOD) activity, and glutathione (GSH) content. The expression levels of Bcl-2 and PDGF were significantly decreased, while the expression levels of CTGF and BAX were significantly increased in the IM group. The l-carnitine treatment successfully protected the heart as indicated by the improvement of the biochemical and histopathological parameters. l-carnitine didn't affect the serum concentration of IM and increased intracellular concentration in the combination-treated group as measured by the mass spectrometer. Conclusion: l-carnitine abrogated IM-induced cardiac damage and apoptosis via PDGF/PPARγ/MAPK pathways.