Stephen Meltzer cultivated a gastro-oesophageal junction (GEJ) organoid from healthy human tissue and used CRISPR‒Cas9 gene editing technology to knock out two key tumour suppressor genes, TP53 and Cyclin Dependent Kinase Inhibitor 2 A (CDKN2A), thus revealing the mechanism of early GEJ tumour development [111]. This evidence concerns the gene CDKN2A and neoplasm.