# The YYR (YY1- RKIP) Regulatory Axis in the pathogenesis of Cancer and Immune Evasion

## TL;DR

This paper explores how the YY1 and RKIP proteins interact in cancer, influencing tumor growth and immune evasion, and suggests targeting this interaction for new therapies.

## Contribution

The paper introduces the YYR regulatory axis as a novel framework to explain the opposing roles of YY1 and RKIP in cancer progression and immune evasion.

## Key findings

- YY1 promotes cancer while RKIP suppresses it, with their inverse expression linked to various cancers.
- The YYR axis influences tumor aggressiveness, immune suppression, and treatment resistance.
- Targeting YY1 inhibition and RKIP induction is proposed as a new therapeutic strategy.

## Abstract

The transcription factor Yin Yang 1 (YY1) and the Raf kinase inhibitory protein (RKIP) represent two molecular entities with diametrically opposed roles in cancer biology. They are key modulators of multiple cellular processes, including apoptosis, metastasis, and cell survival. YY1 functions predominantly as an oncogenic driver, promoting tumorigenesis, epithelial-mesenchymal transition (EMT), immune evasion, and resistance to chemo-immuno-therapy. In contrast, RKIP acts as a metastasis suppressor and chemo-immuno-sensitizer, inhibiting critical oncogenic signaling pathways. The inverse correlation between high YY1 and low RKIP expressions has been observed across various malignancies (such as prostate cancer, melanoma, colorectal cancer, cervical cancer, hematologic malignancies, etc.), suggesting a tightly regulated molecular axis influencing tumor progression and therapeutic response. This review systematically examines the contrasting roles of YY1 and RKIP in cancer pathogenesis (e.g. cell proliferation and cell cycle, angiogenesis, immune cells infiltration and immunosuppressive TME, check point inhibitors, resistance to apoptosis, cell energetics, etc.). Based on their opposing activities, we propose the term YYR–the YY1–RKIP regulatory network– to explain the interplay. YYR captures the bidirectional and context-dependent nature of their relationship for understanding transcriptional programming, immune suppression, tumor aggressiveness, and therapeutic resistance in cancer.

Understanding the dynamics of the YYR axis may offer new insights into prognostic markers and therapeutic strategies aimed at restoring tumor suppressor function and overcoming treatment resistance. Accordingly, we explore potential therapeutic strategies aimed at targeting YYR.

This figure represents the opposing activities mediated by the tumorigenic oncogene YY1 and the tumoricidal tumor suppressor RKIP.

YYR represents a bidirectional regulatory framework: YY1 represses RKIP, while RKIP.

indirectly modulates YY1 activity through inhibition of YY1-driven pathways.

RKIP is a tumor suppressor usually under expressed in cancer.

A dysregulated YYR mediates the pathogenesis and immune evasion in cancer.

A new therapeutic modality is to target the inhibition of YY1 and the induction of RKIP.