Lack of impact of OCTN1 gene polymorphisms on clinical outcomes of gabapentinoids in Pakistani patients with neuropathic pain

Background and objective

Gabapentinoids are the first-line drugs for neuropathic pain. These drugs are the substrate of organic cation transporter (OCTN1) for renal excretion and absorption across the intestinal epithelium. Gabapentinoids exhibit wide interindividual variability in daily dosage and therapeutic efficacy which makes titration regimens prolonged for optimal efficacy. The present study aimed to investigate the possible influence of the single nucleotide polymorphism (SNP) of OCTN1 on therapeutic efficacy and safety of gabapentinoids in neuropathic pain patients of the Pakistani population.

Methods

Four hundred and twenty-six patients were enrolled in the study. All participants were genotyped for OCTN1 rs1050152 and rs3792876 by PCR-RFLP method and followed up for eight weeks. The therapeutic outcomes of gabapentinoids, reduction in pain score, inadequate or complete lack of response, adverse events (AEs) in responders and discontinuation of treatment on account of AEs were recorded for all patients.

Results

There was no significant association of genotypes and alleles of both SNPs on the clinical response of gabapentinoids (P ˃ 0.05). Similarly, significant differences were not found in the reduction of pain scores and AEs among different genotypes in the responders. The present study has reported the association of OCTN1 rs1050152 and rs3792876 polymorphisms with clinical outcomes of gabapentinoids for the first time in the real-world clinical setting.

Conclusion

Our results suggest a lack of influence of OCTN1 genetic variants in the determination of clinical response to gabapentinoids in patients with neuropathic pain in the Pakistani population. These findings signify the role of renal functions in predicting the interindividual variability to therapeutic responsiveness of gabapentinoids.

Prevalence of EBV, CMV, and HPV in oral squamous cell carcinoma patients in the Pakistani population

Many studies have proposed an important role of viruses in the pathogenesis of oral cancer. The present study aimed to find out the prevalence of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human papillomavirus (HPV) among patients with oral squamous cell carcinoma (OSCC) in a Pakistani cohort. We investigated tissue samples obtained from 58 patients with OSCC using the polymerase chain reaction assay. No sample was positive for HPV. EBV was identified in 15 patients (25.86%), and CMV in three patients (5.17%). Coinfection with one or more viruses was detected in two cases and was coinfection with EBV and CMV. These results suggest a low prevalence of these viruses in OSCC patients in the Pakistani population compared to most other countries where the prevalence of these viruses has been reported in the past. Nevertheless, further studies are necessary to determine the potential role of EBV and the possible importance of CMV as an infection cofactor in oral cancer.