Molecular pathological predictive diagnostics in a patient with non-small cell lung cancer treated with crizotinib therapy: A case report

Biomarkers in Non-Small Cell Lung Cancers: Indian Consensus Guidelines for Molecular Testing

Novel molecular targets and promising targeted therapies have reshaped diagnostics in patients with advanced non-small cell lung cancer (NSCLC). Despite this progress, the implementation of molecular screening to identify predictive biomarkers in Indian clinical and pathology settings has been challenging due to operational and logistical constraints. This consensus guideline brings together medical oncologists, molecular pathologists and pathologists from India to provide a quick and competent reference for biomarker testing in NSCLC. The guideline summarizes the importance of targetable mutations in NSCLC such as epidermal growth factor receptor (EGFR), rearrangements in anaplastic lymphoma kinase and receptor tyrosine kinase encoded by ROS-1 gene, overexpression of programmed cell death ligand-1 and resistant EGFR mutations. It reaffirms recommendations from international working groups, discusses vulnerable pre-analytical procedures and provides a balanced review on the pros and cons of different diagnostic tests (immunohistochemistry, fluorescence in situ hybridization, polymerase chain reaction-based testing and next-generation sequencing). The document also provides an algorithm to aid diagnostic decision-making and a checklist to assess the quality of testing laboratories that will help the medical oncologists make an informed choice. Overall, these recommendations are based on evidence and clinical experience and will aid policymakers, oncologists, health care practitioners and pathologists who strive to implement molecular strategies and make informed decisions for improved care in NSCLC in India.Funding: AstraZeneca Pharma India Limited.

lincROR influences the stemness and crizotinib resistance in EML-ALK+ non-small-cell lung cancer cells

Introduction

Echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) is identified as an important pathogenic factor in patients with non-small-cell lung cancer (NSCLC) and could induce a stem-like phenotype in NSCLC cells. Crizotinib is commonly used for EML4-ALK⁺ NSCLC treatment, but its acquired resistance results in tumor recurrence. Long intergenic noncoding RNA, regulator of reprogramming (lincROR) is related to the acquisition and maintenance of self-renewal and stemness features of cancer stem cells. It has been documented that lincROR is implicated in chemoresistance. However, the correlations of lincROR and EML4-ALK in stem cell-like properties and of lincROR and crizotinib resistance in NSCLC cells are yet to be elucidated.

Patients and methods

In the present study, we investigated the expression profile of lincROR in EML-ALK NSCLC tissues, and the potential role of lincROR in prognosis was then analyzed. Subsequently, its association with stem cell-like properties of EML-ALK⁺ NSCLC cells was determined. Furthermore, the correlation of lincROR with crizotinib and the effects of lincROR and crizotinib on cell viability of EML4-ALK⁺ NSCLC cells were all explored.

Results

The results showed that lincROR expression was upregulated in EML4-ALK⁺ NSCLC tissues relative to EML4-ALK^- NSCLC tissues. Low-expressed lincROR was related to a favorable prognosis of patients with EML-ALK NSCLC. lincROR overexpression could enhance the stemness features of EML-ALK⁺ NSCLC cells which were repressed by ALK knockdown.

Conclusion

We found that lincROR expression was significantly inhibited because of the increased concentration of crizotinib in EML4-ALK⁺ NSCLC cells. Furthermore, lincROR overexpression increased cell viability of EML4-ALK⁺ NSCLC cells, which was impaired by crizotinib. Conjointly, these results suggested the important role of lincROR in EML-ALK⁺ NSCLC. lincROR may serve as a potential therapeutic target to overcome chemotherapy resistance in EML-ALK⁺ NSCLC.