PPP1R1B and gastric cancer: In the early 2000s, El-Rifai et al. discovered that DARPP-32 and its novel transcriptional splice variant are frequently amplified and upregulated in gastric cancer.9,18 The N-terminally truncated isoform of DARPP-32, named t-DARPP, uses a unique alternative first exon located within intron 1 of DARPP-32.