Circular RNA protein tyrosine kinase 2 (circPTK2) (circPTK2)

Circular RNA protein tyrosine kinase 2 (circPTK2) is a stable, non-coding RNA molecule formed through the back-splicing of exons from the PTK2 gene, which also encodes Focal Adhesion Kinase (FAK) [1, 6]. It primarily functions as a molecular sponge for various microRNAs, such as miR-136-5p and miR-429, thereby regulating the expression of downstream oncogenic or tumor-suppressive genes [1, 11]. Additionally, circPTK2 can interact directly with proteins like vimentin and MDM2 to modulate cellular processes including the epithelial-mesenchymal transition (EMT) and cellular senescence [5, 6]. In many cancers, including colorectal and lung cancer, circPTK2 is significantly upregulated and correlates with advanced clinical stages, metastasis, and poor patient prognosis [3, 10]. It has also been implicated in promoting resistance to chemotherapeutic agents like 5-fluorouracil and oxaliplatin [1, 7]. Due to its high stability and tissue-specific expression, circPTK2 is being investigated as both a promising diagnostic biomarker and a potential therapeutic target for RNA-based interventions [3, 6, 14].

Other names

hsa_circ_0005273hsa_circ_0008305hsa_circ_0003221circRNA PTK2

Functions as a competitive endogenous RNA (ceRNA) by sponging microRNAs to release target mRNAs from post-transcriptional repression, and acts as a protein scaffold to stabilize oncogenic proteins or sequester regulatory factors.