Biology subjects

Luby-Phelps, K.

Publications and source records attributed to Luby-Phelps, K..

3 recordsLinked to original sources

bioRxiv2024

SMURF1/2 are novel regulators of WNK1 stability

Angiogenesis is essential for remodeling and repairing existing vessels, and this process requires signaling pathways including those controlled by transforming growth factor beta (TGF-{beta}). We have previously reported crosstalk between TGF-{beta} and the protein kinase With No lysine (K) 1 (WNK1). Homozygous disruption of the gene encoding WNK1 results in lethality in mice near embryonic day E12 due to impaired angiogenesis and this defect can be rescued by endothelial-specific expression of an activated form of the WNK1 substrate kinase Oxidative Stress-Responsive 1 (OSR1). However, molecular processes regulated via a collaboration between TGF-{beta} and WNK1/OSR1 are not well understood. Here we show that WNK1 interacts with the E3 ubiquitin ligases SMURF1/2. In addition, we discovered that WNK1 regulates SMURF1/2 protein stability and vice versa. We also demonstrate that WNK1 activity regulates TGF-{beta} receptor levels, in turn, controlling TGF-{beta} signaling.

biochemistry↗

bioRxiv2024

Cervical collagen network porosity assessed by SHG endomicroscopy distinguishes preterm and normal pregnancy - a pilot study

Structured AbstractO_ST_ABSBackgroundC_ST_ABSPreterm birth (PTB) is a global public health issue affecting millions of newborns every year. Orchestrated remodeling of the cervix is essential for normal pregnancy and birth, while PTB is closely related with premature cervical ripening and loss of cervical mechanical strength. The structure and organization of fibrillar collagen in the extracellular matrix are of vital importance to the biomechanical properties of the cervix. Second harmonic generation (SHG) microscopy has proved capable of revealing the progressive changes in cervical collagen morphology over the course of pregnancy. To translate this promising imaging technology to clinical practice, a flexible SHG endomicroscope has long been envisaged for label-free, non-invasive visualization of cervical collagen architecture and for assessment of PTB risk. ObjectiveTo evaluate the potential of our newly-developed SHG endomicroscope for imaging-based differentiation of cervical collagen architecture between normal pregnant mice and RU486/mifepristone-induced PTB mouse models. Study DesignWe undertook endomicroscopy SHG imaging of cervical collagen on two types of ex vivo samples: 1) frozen cervical tissue sections ([~]50 {micro}m thick) and 2) resected intact cervices, and performed SHG-image-based quantitative collagen morphology analysis to distinguish RU486 mouse models from normal pregnant mice. ResultsEndomicroscopic SHG images of cervical tissue sections from mifepristone-treated mouse models exhibit statistically larger collagen fiber diameter, increased pore size, and reduced pore numbers than those of normal pregnant mice. Similar changes are also observed on SHG images of subepithelial collagen fibers acquired from intact cervices by the endomicroscope. ConclusionThe experiment results demonstrated that SHG endomicroscopy along with quantitative image analysis holds promising potential for clinical assessment of cervical collagen remodeling and preterm birth risk.

bioengineering↗

bioRxiv2019

Stromal Hedgehog pathway activation by IHH suppresses lung adenocarcinoma growth and metastasis by limiting reactive oxygen species

Activation of the Hedgehog (Hh) signaling pathway by mutations within its components drives the growth of several cancers. However, the role of Hh pathway activation in lung cancers has been controversial. We demonstrate that the Hh signaling pathway is activated in lung stroma in a paracrine manner. Genetic deletion of Shh in autochthonous murine lung adenocarcinoma had no effect on survival. Early abrogation of the pathway by an anti-SHH/IHH antibody 5E1 led to significantly worse survival with increased tumor and metastatic burden. Loss of IHH by in vivo CRISPR led to more aggressive tumor growth suggesting that IHH, not SHH, activates the pathway in stroma to drive its tumor suppressive effects - a novel role for IHH in the lung. Tumors from mice treated with 5E1 had decreased blood vessel density and increased reactive oxygen species (ROS). Treatment of KP mice with 5E1 and N-acetylcysteine, as a ROS scavenger, decreased tumor ROS levels, inhibited tumor growth and prolonged mouse survival suggesting that increased ROS levels from stromal Hh pathway inhibition spurred lung tumor growth. Thus, IHH induces stromal Hh pathway activation to suppress tumor growth and metastases, in part, by limiting ROS production.

cancer biology↗