ROCK inhibition modulates the senescence‐associated secretory phenotype (SASP) in oral keratinocytes

Abstract

Senescent cells accumulate in different organs and develop a senescence-associated secretory phenotype (SASP), associated with the development of age-related pathologies. The constitution of the SASP varies among cell types and with the method of senescence induction; nevertheless, there is substantial overlap among SASPs, especially the presence of pro-inflammatory cytokines such as IL-1, IL-1, IL-6 and IL-8. These cytokines are highly conserved among SASPs and are implicated in the development of several cancers. Here, we report that ROCK inhibition by Y-27632 reduces levels of IL-1, IL-1, IL-6 and IL-8 secreted by senescent normal and dysplastic oral keratinocytes without affecting the permanent cell growth arrest. The data indicate some inflammatory genes downregulated by Y-27632 remain downregulated even after repeated passage in the absence of Y-27632. We propose ROCK kinase inhibition as a novel alternative to current strategies to modulate the inflammatory components of the SASP, without compromising the permanent cell growth arrest. This observation potentially has wide clinical applications, given the involvement of senescence in cancer and a wide range of age-related disease. It also suggests care should be exercised when using Y-27632 to facilitate cell expansion of primary cells, as its effects on gene expression are not entirely reversible.

The Extracellular Metabolome Stratifies Low and High Risk Potentially Premalignant Oral Keratinocytes and Identifies Citrate as a Potential Non-Invasive Marker of Tumour Progression

“…However, senescent cells secrete an array of proteins that have important functions in age-related diseases and cancers, known as the senescence-associated secretory phenotype (SASP) [21]; recent data suggests that senescent keratinocytes secrete some SASP factors [22] and metabolites in vitro and, in mouse models of epidermal SCC, in vivo [23,24]. Therefore, LR MPPOL keratinocytes may well have a tumour-promoting role in the pre-cancerous field of OSCC.…”

Overcoming the senescence‐associated secretory phenotype (SASP): a complex mechanism of resistance in the treatment of cancer

“…Similarly, Wang et al (2019) reported that fibroblast growth factor receptor (FGFR) inhibitor resistance in lung cancer is initially mediated by the cancer cell secretome activating STAT3 signalling; however, they also showed that this resistance could be enhanced via interactions with both fibroblasts and macrophages [74]. Rho-associated protein kinase (ROCK) inhibitors have recently been reported to improve chemotherapy delivery and reduce metastases in cancers such as pancreas and breast [75][76][77]. Interestingly, Niklander et al (2020) found that the ROCK inhibitor Y-27632 could decrease activity of several factors within the pro-inflammatory SASP, without altering cell cycle arrest in oral dysplastic keratinocytes [78].…”

“…Rho-associated protein kinase (ROCK) inhibitors have recently been reported to improve chemotherapy delivery and reduce metastases in cancers such as pancreas and breast [75][76][77]. Interestingly, Niklander et al (2020) found that the ROCK inhibitor Y-27632 could decrease activity of several factors within the pro-inflammatory SASP, without altering cell cycle arrest in oral dysplastic keratinocytes [78]. The authors show that this is mediated by IL-1 inhibition from Y-27632, which in turn regulated the secretion of protumourigenic SASP components such as IL-6 and IL-8 [78].…”

The emerging role of cellular senescence in complications of COVID-19

“…This phenotype results from the downregulation of the essential cell cycle proteins Cyclin A, CKS1 and CDK1 [53] . Therefore, ROCK inhibition could open up a new spectrum for the removal of cellular senescence [ 32 , 54 , 55 ]. The NF-κB system is an evolutionarily conserved signaling pathway triggered by immune activation and various external and internal warning signs associated with senescence and the aging process, such as oxidative and genotoxic stress [56] .…”

“…This phenotype results from the downregulation of the essential cell cycle proteins Cyclin A, CKS1 and CDK1 [53] . Therefore, ROCK inhibition could open up a new spectrum for the removal of cellular senescence [ 32 , 54 , 55 ].…”