Novel human-derived EML4-ALK fusion cell lines identify ribonucleotide reductase RRM2 as a target of activated ALK in NSCLC.

INTRODUCTION: Echinoderm microtubule-associated protein-like 4 (EML4)-Anaplastic Lymphoma Kinase (ALK) rearrangements occur in 3% to 7% of lung adenocarcinomas and are targets for treatment with tyrosine kinase inhibitors (TKIs). Here we have developed three novel EML4-ALK-positive patient-derived Non-Small-Cell-Lung-Cancer (NSCLC) cancer cell lines, CUTO8 (variant 1), CUTO9 (variant 1) and CUTO29 (variant 3) and included a fourth ALK-positive cell line YU1077 (variant 3) to study ALK-positive signaling and responses. Variants 1 and 3 are the most common EML4-ALK variants expressed in ALK-positive NSCLC, and currently cell lines representing these EML4-ALK variants are limited. MATERIALS AND METHODS: Resazurin assay was performed to evaluate cell viability. Protein levels were determined using western blotting. RNA sequencing was performed in all four cell lines to identify differentially expressed genes. Whole-genome sequencing was performed to determine the presence of EML4-ALK fusion and ALK tyrosine kinase inhibitor resistance mutations. RESULTS: In this study, we have confirmed expression of the corresponding ALK fusion protein and assessed their sensitivity to a range of ALK tyrosine kinase inhibitors. These patient derived cell lines exhibit differential sensitivity to lorlatinib, brigatinib and alectinib, with EML4-ALK variant 3 containing cell lines exhibiting increased sensitivity to lorlatinib and brigatinib as compared to alectinib. These cell lines were further characterized by whole genome sequencing and RNA-seq analysis that identified the ribonucleotide reductase regulatory subunit 2 (RRM2) as a downstream and potential therapeutic target in ALK-positive NSCLC. CONCLUSION: We provide a characterization of four novel EML4-ALK-positive NSCLC cell lines, highlighting genomic heterogeneity and differential responses to ALK TKI treatment. The RNA-Seq characterization of ALK-positive NSCLC CUTO8, CUTO9, CUTO29 and YU1077 cell lines reported here, has been compiled in an interactive ShinyApp resource for public data exploration (https://ccgg.ugent.be/shiny/nsclc_rrm2_2022/).

Isolated coronal urethral duplication in an adolescent presenting with enuresis.

SUMMARY: This report describes an isolated urethral duplication in the coronal plane in a child referred with primary 'enuresis'. This presentation is unique because duplications usually occur in the sagittal plane. In patients with suspected urethral duplication, magnetic resonance imaging in conjunction with catheterisation of the distal duplicate opening accurately delineates the abnormality, so that individualised treatment strategies can be considered.

The consequences of punching glass.

We carried out a retrospective and prospective study of 67 patients who had sustained hand injuries from punching glass over a period of 33 months. All had consumed alcohol and had argued with a partner. The mean age was 25 years, 90% were male and 56% were unemployed. Seventy per cent of injuries occurred between 23.00 and 04.00 hours. Total damage included division of 149 tendons, 33 nerves and nine arteries. Fifty-two per cent of patients required admission for more than 1 day. The mean number of follow-up visits was 3.6 and the majority needed hand therapy and occupational therapy services. Cost per injury was estimated as 1,120 pounds. Such injuries cause major disability in an already disadvantaged section of society. The challenge is to educate the susceptible patient group.