Overcoming resistance by ALK compound mutation (I1171S + G1269A) after sequential treatment of multiple ALK inhibitors in non‐small cell lung cancer

Abstract

Background Anaplastic lymphoma kinase (ALK) fusion genes are found in 3%–5% of non‐small cell lung cancers (NSCLCs). ALK inhibitors show a very high response rate to ALK‐positive NSCLCs. However, the emergence of acquired resistance is inevitable. In this study, we investigated the drugs for overcoming resistance especially compound mutations after sequential treatment with crizotinib, alectinib, and lorlatinib. Method Next‐generation sequencing (NGS) and Sanger sequencing were performed on a liver biopsy tissue obtained from a clinical case. Ba/F3 cells in which mutant EML4‐ALK were overexpressed were prepared, and cell viability assay and immunoblotting were performed to check the sensitivity of five independent ALK inhibitors. Results I1171S + G1269A double mutation was identified by NGS and Sanger sequencing on a liver biopsy tissue from a patient who relapsed on lorlatinib treatment. Ceritinib and brigatinib—but not other ALK inhibitors—were active against the compound mutations in the cell line model. Conclusions With the sequential ALK inhibitors treatment, cancer cells accumulate new mutations in addition to mutations acquired previously. The identified compound mutation (I1171S + G1269A) was found to be sensitive to ceritinib and brigatinib, and indeed the patient's tumor partially responded to ceritinib. Key points ALK compound mutation was found in a clinical sample that was resistant to lorlatinib after sequential ALK‐tyrosine kinase inhibitor (TKI) treatment. Ceritinib and brigatinib are potential overcoming drugs against ALK I1171S + G1269A double mutation.

A patient with ALK‐positive lung adenocarcinoma who survived alectinib‐refractory postoperative recurrence for 4 years by switching to ceritinib

“…11 Some researchers have reported that tumors with compound mutations such as I1171N with L1196M or I1171N with G1269A are also sensitive to ceritinib. 7,12 There is a study suggesting that epithelial mesenchymal transition (EMT) is associated with resistance to ALK-TKI. 13 Lung adenocarcinoma before ALK-TKI treatment was E-cadherin-positive and vimentin-negative, but it changed to E-cadherin-negative and vimentin-positive during progression after treatment with ALK-TKIs.…”

Resistance to anaplastic lymphoma kinase inhibitors: knowing the enemy is half the battle won

“…However, changeable scenarios may emerge such as the case of a patient treated with the sequence of crizotinib-ceritinib-lorlatinib, who developed a post-lorlatinib L1198F mutation, along with the post-crizotinib C1156Y, and surprisingly responded to crizotinib; this double compound mutation C1156Y/ L1198F re-sensitizes patient's tumor to first-generation ALKi (29). Also the I1171S/G1269A mutation, identified in a liver lesion at progression to lorlatinib, turned out to be sensitive to ceritinib and brigatinib and the patient responded to treatment with ceritinib (30).…”

Utility of the Ba/F3 cell system for exploring on‐target mechanisms of resistance to targeted therapies for lung cancer

“…D, Patterns of base substitutions identified in our recent studies [19][20][21] that used Ba/F3 models and N-ethyl-N-nitrosourea (ENU) mutagenesis. Secondary mutation data are from following references:: EGFR mutation 6,16,28-30,32,36,39-43,97-109 , ALK fusion [45][46][47][48][49]51,[53][54][55][56][57][110][111][112][113][114][115][116][117] , ROS1 fusion 17,53,59,63,64,[118][119][120][121][122][123] , RET fusion 69,70,[124][125][126] , NTRK fusion 73,75,76,127 , and MET exon 14 skipping 20,21,81,[83][84][85][86]…”

“…D, Patterns of base substitutions identified in our recent studies 19‐21 that used Ba/F3 models and N‐ethyl‐N‐nitrosourea (ENU) mutagenesis. Secondary mutation data are from following references:: EGFR mutation 6,16,28‐30,32,36,39‐43,97‐109 , ALK fusion 45‐49,51,53‐57,110‐117 , ROS1 fusion 17,53,59,63,64,118‐123 , RET fusion 69,70,124‐126 , NTRK fusion 73,75,76,127 , and MET exon 14 skipping 20,21,81,83–86,88,89,95,128‐132 . *In RET and NTRK fusions, the resistance mutations that emerged in other type of cancers are also included.…”