Pharmacogenomic Single Nucleotide Polymorphism (SNP) Variants As Predictors of Toxicity Phenotypes in the Treatment of Acute Childhood Leukemia

Introduction: Despite cure rates in acute lymphoblastic leukemia (ALL) exceeding 90% in clinical trials, morbidity due to drug toxicities is high. Genetic polymorphisms can influence gene expression and activity, impacting pharmacokinetics and causing inter-individual variation in drug levels, which contributes to toxicity if levels are high or relapse if levels are low. We hypothesize that pharmacogenomic testing will identify patient specific variations in genes involved in metabolism of cytotoxic agents. This knowledge will allow clinicians to optimize therapy by providing pharmacogenomics based biomarkers related to increased toxicities. Data has shown that treatment interruptions and omissions due to toxicities affect outcomes and morbidities in children with cancer. Objective : To correlate pharmacogenomic biomarkers with toxicity phenotypes in children receiving therapy for ALL. Methods: This cross-sectional study involved subjects at a tertiary academic center (Fig. 1A). Subjects aged 1 year to 26 years with ALL treated after May 2012 were eligible. A total of 75 patients treated between 2012 and 2020 were included. Pharmacogenomic testing was performed on peripheral blood. Genomic DNA was tested for 118 single-nucleotide polymorphisms (SNP) in 55 genes for transport and metabolism of cytarabine, vincristine, methotrexate, dauno/doxorubicin, and mercaptopurine/thioguanine were analyzed using the Sequenom-based genotyping that uses MALDI-TOF based chemistry. SNPs were tested using logistic regression models for association with toxicities in additive, dominant, and recessive modes of inheritance. CTCAE v4.0 was used for grading all toxicities during the first 100 days of therapy. For endocrine (endo) and neurological (neuro) toxicities, 25 patients exhibited between grade 1-3 toxicities. For gastrointestinal (GI) toxicities, 25 patients exhibited between grade 2-3 toxicities. For hematological (heme) toxicities, 11 patients exhibited between grade 2-4 toxicities. Odds ratio and 95% confidence interval were calculated for each test and SNPs with association P-value <0.05 were considered significant. To conduct multivariable SNP combinations analysis, SNPs with univariate association p-value <0.1 were selected for each toxicity, and then SNP combinations (up to 3 SNPs per model) were tested for association with each toxicity. The combination model with the 1000 permutation p-value <0.05 and lowest BIC value was selected to build a SNP score after considering the mode of inheritance and the direction of association with the toxicity for the individual genotypes. A SNP score was generated by summation of genotype scores for the individual SNPs passing the top model. Patients were further classified into either of the 3 following SNP score groups: >0, 0 or <0. Results: For a GI toxicity score derived from 3 SNPs (TYMS-rs151264360, FPGS-rs1544105, and GSTM5-rs3754446), patients with >0 score had 79% incidence of GI toxicity (N=67) as compared to 10% in patients with score of 0 and 8% in patients with score <0 (p=2.07E-05, Fig 1B). For the SNP score (AKR1C3-rs6621365, ABCB1-rs4148737, and CTPS1-rs12067645) generated for heme toxicity, higher SNP scores were associated with high toxicity (p=0.003, Figure 1C). For neurotoxicity, the 3 SNPs (DCTD-rs6829021, SCL28A3-rs17343066, and CTPS1-rs12067635) involved were all in cytarabine metabolic pathway and predicted greater neurotoxicity (56%) with a score of >0; no toxicity was observed in patients with neurotoxicity score of <0 (p=0.0005, Fig. 1D). For SNP endo toxicity score (AKR1C3-rs1937840, TYMS-rs2853539, and CTS-rs648743), we observed 91% incidence of endo toxicity in patients with toxicity score of >0 (p=4.7E-08, Fig. 1E). None of the patients with a score of <0 experienced endo toxicity. Discussion: We identified germline SNPs predictive of toxicity phenotypes in a cohort of 75 subjects with ALL. The results of our multivariable SNP combination analysis suggest susceptibility to chemotherapy-induced toxicities is likely multigenic in nature. Instead of a single SNP approach, identification of combinations of mutations in drug pathways increases the robustness of predicting a patient's response to chemotherapy. Our results provide promising SNP models that can help establish clinically relevant biomarkers allowing for individualization of cancer therapy to optimize treatment for each patient. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Unsatisfied Reporting Quality of Clinical Trials Evaluating Immune Checkpoint Inhibitor Therapy in Cancer

BackgroundMore and more immune-oncology trials have been conducted for treating various cancers, yet it is unclear what the reporting quality of immune-oncology trials is,and characteristics associated with higher reporting quality.ObjectiveThis study aims to evaluate the reporting quality of immune-oncology trials.MethodsThe PubMed and Cochrane library were searched to identify all English publications of clinical trials assessing immunotherapy for cancer. Reporting quality of immune-oncology trials was evaluated by a quality score with 11 points derived from the Trial Reporting in Immuno-Oncology (TRIO) statement, which contained two parts: an efficacy score of 6 points and toxicity score of 5 point. Linear regression was used to identify characteristics associated with higher scores.ResultsOf the 10,169 studies screened, 298 immune-oncology trial reports were enrolled. The mean quality score, efficacy score, and toxicity score were 6.46, 3.61, and 2.85, respectively. The most common well-reported items were response evaluation criteria (96.0%) and toxicity grade (98.7%), followed by Kaplan-Meier survival analyses (80.5%). Treatment details beyond progression (12.8%) and toxicity onset time and duration (7.7%) were poorly reported. Multivariate regression revealed that higher impact factor (IF) (IF >20 vs. IF <5, p < 0.001), specific tumor type (p = 0.018 for lung, p = 0.021 for urinary system, vs. pan cancer), and a certain kind of immune checkpoint blocking agent (p < 0.001 for anti-PD-1 or multiagents, vs. anti-CTLA-4) were independent predictors of higher-quality score. Similar independent predictive characteristics were revealed for high-efficacy score. Only IF >20 had a significant high-toxicity score (p < 0.001).ConclusionImmune-oncology trial reports presented an unsatisfied quality score, especially in the reporting of treatment details beyond progression and toxicity onset time and duration. High IF journals have better reporting quality. Future improvement of trial reporting was warranted to the benefit-risk assessment of immunotherapy.

MTHFR 677T-1298C haplotype in acute lymphoblastic leukemia: Impact on methotrexate therapy

Introduction Functional variants of the Methylenetetrahydrofolate reductase ( MTHFR) gene, the C677T and A1298C, have largely investigated in pharmacogenomics of Methotrexate (MTX) in acute lymphoblastic leukemia (ALL), yet the conclusions are inconsistent. In addition; most of these studies do not analyze haplotypes. Here, we investigate the MTHFR 677/1298 genotypes and the 677-1298 haplotype and characterize the MTX response in Northern African ALL patients. Methods Genomic DNA was extracted from whole venous from a total of 28 patients with ALL. Genotyping were carried out with restriction fragment length polymorphism (RFLP). A toxicity score (TS) is calculated for each patient and correlate to the haplotype. Results The allelic frequency of MTHFR 677T-1298C haplotype was 10.7% in ALL patients. According to the toxicity’s score (TS) there was no significant differences between haplotype groups (p = 0.79): TS was higher with wild type of MTHFR (TS = 3.43; SEM ± 0.85) followed by combined genotype (677T-1298C) (TS = 2.67; SEM ± 0.88) and isolated variant (C677T or A1298C) (TS = 2.64; SEM ± 0.92). Conclusion Despite the limitation of this study; our results suggest that the MTHFR 677T-1298C haplotype is common in ALL and may be a promising HD-MTX chemotherapy-related adverse effects biomarker.

A Descriptive Study to Assess the Association of Geriatric Score with Observed Chemo Toxicity in Cancer Patients Older than 60 Years

Introduction Cancer is the leading cause of death worldwide with elderly patients being predominantly affected. There seems to be a bias against administering chemotherapy to elderly patients with fewer elderly patients receiving chemotherapy as compared with their stagematched younger patients because of concerns about their capacity to endure treatment. To make personalized treatment decisions and to anticipate serious adverse effects, a toxicity prediction tool that can be computed at the bedside is the need of the hour. This well-validated score has not been tested in the Indian population. So, we decided to test the same score in our patients and try to correlate the score with the observed toxicity. Objectives This study was aimed to determine geriatric functional status by means of a standardized geriatric score and to correlate geriatric score with observed chemo toxicity. Materials and Methods Fifty consecutive elderly patients (age > 60 years) with a diagnosis of cancer and scheduled for chemotherapy were recruited. These patients were evaluated using the geriatric assessment tool which is based on functional, nutritional, and psychological status. After that patient’s pretherapy, chemo toxicity score or geriatric score was calculated using a published well-validated tool that consisted of 11 prechemotherapy variables as follows:a) Age of patient,b) Cancer typec) Planned chemotherapy dose,d) Planned number of chemotherapy drugse) Hemoglobin,f) Creatinine clearanceg) Geriatric questions like -i. How is your hearing?ii. Number of falls in past 6 months?iii. Can take your own medicines?iv. Does your health limit you in walking one block ? during past 4 weeksv. How much of time has your physical health or emotional problems interfered with your social activities (like visiting with friends, relatives etc.)The patients were then followed from the beginning to the end of six cycles of their chemotherapy regimen. Toxicities were noted after each clinical encounter by using the NCI-CTCAE, version 3.0.25. Results General characteristics: the mean age of participants was 66 years (standard deviation [SD] = 4.6 and range: 60–85 years). Of them, 60% received polychemotherapy and 82% received standard doses of chemotherapy. The mean score on activities of daily living was 66.7, comorbidity score was 2.7, the psychological scale was 63.8, the social-activity scale was 54.3, and social-support scale was 64.1. The mean pretherapy toxicity score is 7.24 according to the toxicity calculator. At least one grade 3 to 5 toxicity occurred in 30% of the patients (66% of grade 3, 20% of grade 4, and 13.3% of grade 5). The correlation between the predicted score and observed graded toxicity score by Pearson’s scale (α = 0.05) was 0.63. Conclusion The prediction model is easy to use, thus increasing the feasibility of incorporation in daily practice is important. It may enable oncologists to better assess the risk/benefit ratio and to adjust the treatment accordingly.

Effect of vitamin E supplementation to diet containing herbal mixture on performance and carcass quality of broiler chickens

The present study was conducted to evaluate the effect of vitamin E supplementation to diet containing herbal mixture on performance, meat quality, hematological status and fat deposition of broiler chickens. Eighty 15-day-old female broilers were distributed into 2 treatment groups with 4 replications (10 female broilers of each replication) as follows. Feed with FSBL plus 1 g of turmeric and 2 g garlic (P1) and Feed of P1 plus vitamin E (P2). Vitamin E supplementation had no effect on performance, carcass weight, meat bone ratio, drip loss and cooking loss, gizzard, spleen, proventriculus, gallbladder, heart, caecum, intestine, fat depot in abdomen, sartorial, neck, heart, proventriculus, and liver as expressed by fatty liver score, blood triglyceride, cholesterol, LDL and HDL concentrations, moisture, and fat and ash contents of meats. However, it reduced liver weight, toxicity score, gizzard fat depot and meat protein. In conclusion, vitamin E supplementation to diet containg herbal mixture reduced meat protein, toxicity score, and gizzard fat depot.

Effect of chlorpheniramine on acute dichlorvos poisoning in wistar rats

Introduction: Pesticide poisoning is a serious public health concern worldwide. According to WHO, about 3 million cases occur every year, resulting in more than 250,000 deaths. In response to the problems of unavailability of antidotes and cost in sub-Saharan Africa, this research set out to investigate chlorpheniramine, a cheap and readily available over the counter (OTC) antihistamine for possible antidotal effects on rats acutely poisoned with dichlorvos. Methodology: The antidotal and protective effect of chlorpheniramine a H1 antihistamine on acute toxicity by dichlorvos, an organophosphorus insecticide in wistar rats was investigated and compared with atropine, the standard antidote. Chlorpheniramine (2mg/kg, 4mg/kg, and 8mg/kg), atropine (0.4mg/kg, 0.8mg/kg, and 1.6mg/kg) and dichlorvos (4mg/kg) were all administered intraperitoneally. Dichlorvos at a dose of 4mg/kg induced acute toxicity in the rats observed as tremor, convulsion, defecation, straub tail, recumbence and gasping. Results: Chlorpheniramine significantly (p<0.05) decreased the occurrence of acute signs of toxicity and also delayed the time of onset of signs of poisoning. Chlorpheniramine also prevented death of the animals with 100% survival rate after 2- 24hours of dichlorvos poisoning. Chlorpheniramine also reduced the toxicity score as compared to the control after acute toxicity testing for 14days. Conclusion: The results suggests that chlorpheniramine possesses antidotal effects against dichlorvos induced toxicity in wistar rats comparable to atropine, the standard antidote and showed an additive positive antidotal effect when administered in combination with atropine.