NEK2 promotes trastuzumab resistance in gastric cancer through WTAP/YTHDF1-dependent m6A regulation of FN1.

BACKGROUND

Trastuzumab resistance remains a major challenge in the clinical management of gastric cancer (GC), and effective strategies to overcome resistance are still limited. NEK2 has been implicated in GC progression and therapeutic resistance in several tumor types; however, its role in trastuzumab resistance in GC and the underlying mechanisms remain unclear.

METHODS AND

RESULTS

Trastuzumab-resistant NCI-N87/TR cells were established from parental NCI-N87 cells by stepwise exposure to increasing concentrations of trastuzumab. NEK2 was markedly upregulated in trastuzumab-resistant GC cells. Silencing NEK2 attenuated trastuzumab resistance, as evidenced by decreased cell viability and DNA replication and increased apoptosis, whereas NEK2 overexpression enhanced resistance to trastuzumab. Mechanistically, NEK2 promoted FN1 expression and activated PI3K/AKT signaling, while exogenous FN1 partially rescued the inhibitory effect of NEK2 knockdown on trastuzumab resistance. RNA immunoprecipitation, MeRIP-qPCR, and dual-luciferase reporter assays analyses further showed that WTAP-dependent N6-methyladenosine (m6A) modification at nucleotide 5882 of FN1 mRNA, followed by YTHDF1 recognition, enhanced FN1 mRNA stability and protein expression. Moreover, overexpression of either WTAP or YTHDF1 restored FN1 expression, AKT phosphorylation, and trastuzumab resistance in NEK2-silenced cells.

CONCLUSION

NEK2 promotes trastuzumab resistance in GC by enhancing WTAP/YTHDF1-dependent m6A regulation of FN1, thereby activating PI3K/AKT signaling. These findings suggest that NEK2 may represent a potential therapeutic target for overcoming trastuzumab resistance in GC.