Background of the case: The "recipe" of cancer biology is shaken Published in 1999, this study demonstrated that a combination of specific oncogenes and tumor suppressor genes could transform normal cells into tumor cells, establishing a foundation for modern cancer research. However, serious concerns have recently been raised regarding the reproducibility of the data and the integrity of the images presented in the paper.

Key issues: Reproducibility problems emerge after 25 years The core reasons for Nature’s issuance of an Expression of Concern are:

What is an Expression of Concern? An Expression of Concern (EoC) is an official notice indicating that a serious issue has been identified that could affect the paper’s conclusions, but a final decision (such as retraction) has not yet been reached. It serves as an urgent alert to scientists who may be building on the reported findings to exercise caution when using the data.

Implications: Self‑correction in science and research ethics This case demonstrates that even highly regarded classic studies are not exempt from the fundamental scientific principles of data transparency and reproducibility. While considerable disruption in the field is anticipated, the fact that the scientific community is actively addressing the errors and pursuing the truth is viewed as a positive sign of self‑correction.