Whilst demonstrated extensively in vitro, the control of cell behaviour via modulation of substrate compliance in live tissues has not been accomplished to date. Here we propose that stem cells can be regulated solely through in situ modulation of tissue biomechanics. By first establishing, via high-resolution Brillouin spectro-microscopy, that the outer edge (limbus) of live human corneas has a substantially lower bulk modulus compared to their centre, we then demonstrate that this difference is associated with limbal epithelial stem cell (LESC) residence and YAP-dependent mechanotransduction. This phenotype-through-biomechanics correlation is further explored in vivo using a rabbit alkali burn model. Specifically, we show that treating the burnt surface of the cornea with collagenase effectively restores the tissue’s mechanical properties and its capacity to support LESCs through mechanisms involving YAP suppression. Overall, these findings have extended implications for understanding stem cell niche biomechanics and its impact on tissue regeneration.

Background and Aims: Little is known about metabolic dysfunction-associated steatotic liver disease (MASLD) as a risk factor for hepatocellular carcinoma (HCC) in non-cirrhotic (HCC-NC) patients. In-house developed mouse models with defective lipid-metabolizing enzyme long-chain 3-hydroxy acyl-CoA dehydrogenase (LCHAD), coded by hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit alpha (HADHA) gene, result in MASLD (steatosis) without cirrhosis leading to HCC-NC. The aims of the current investigations are to assess molecular markers and the associated molecular events that may lead to HCC-NC. Methods: cDNA array study of HCC patients was conducted to assess the expression of HADHA transcripts. Differentially expressed proteins identified between wild-type (WT) and heterozygous mice with no cancer (HT) from a previous study were subjected to Ingenuity Pathway Analysis (IPA). Western blotting was performed to assess the expression of proteins. Results: IPA of the differentially expressed proteins between WT and HT mice results in two biological networks (network 1 and network 2), which pointed to an important role of p53 in HCC-NC. Validation of the levels of MDM2 and p53 also highlights the role of MDM2-p53 axis in HCC-NC. All the focus molecules in network 1 and network 2 are either presented as tumor suppressor/promoter of carcinogenesis or serum markers for early HCC diagnosis. The hepatotoxicity report from IPA further identified four functional groups including liver steatosis, glutathione depletion, hepatocellular carcinoma, and liver hyperplasia/hyperproliferation. Conclusions: This study suggests that impaired fatty oxidation may play a role in the development of HCC associated with steatosis but without cirrhosis (HCC-NC). Defective LCHAD is a novel etiology for HCC.