The study explores the non-coding function of mRNA and pseudogene mRNAs in cancer, focusing on the relationship between the *PTEN* tumor suppressor gene and its pseudogene *PTENP1*. The authors hypothesize that these RNAs have a biological role in cancer cells that is independent of their protein-coding function, relying instead on their ability to compete for microRNA binding. They find that *PTENP1* is biologically active and can regulate *PTEN* levels, exerting a growth-suppressive effect. The *PTENP1* locus is selectively lost in human cancer, suggesting a tumor suppressive role. Similar findings are observed for other cancer-related genes with pseudogenes, such as *KRAS*. The study also demonstrates that transcripts of protein-coding genes like *PTEN* can also be biologically active. These findings attribute a novel biological role to expressed pseudogenes and reveal a non-coding function for mRNAs. The authors propose a general model where endogenous mRNA-mediated biology can regulate cellular processes through microRNA decoy mechanisms, suggesting that pseudogenes may act as "perfect decoys" for their ancestral genes.The study explores the non-coding function of mRNA and pseudogene mRNAs in cancer, focusing on the relationship between the *PTEN* tumor suppressor gene and its pseudogene *PTENP1*. The authors hypothesize that these RNAs have a biological role in cancer cells that is independent of their protein-coding function, relying instead on their ability to compete for microRNA binding. They find that *PTENP1* is biologically active and can regulate *PTEN* levels, exerting a growth-suppressive effect. The *PTENP1* locus is selectively lost in human cancer, suggesting a tumor suppressive role. Similar findings are observed for other cancer-related genes with pseudogenes, such as *KRAS*. The study also demonstrates that transcripts of protein-coding genes like *PTEN* can also be biologically active. These findings attribute a novel biological role to expressed pseudogenes and reveal a non-coding function for mRNAs. The authors propose a general model where endogenous mRNA-mediated biology can regulate cellular processes through microRNA decoy mechanisms, suggesting that pseudogenes may act as "perfect decoys" for their ancestral genes.