LRIG1 controls proliferation of adult neural stem cells by facilitating TGFß and BMP signalling pathways.

Adult Neural Stem Cells (aNSCs) in the ventricular-subventricular zone (V-SVZ) are largely quiescent. Here, we characterize the mechanism underlying the functional role of a cell-signalling inhibitory protein, LRIG1, in the control of aNSCs proliferation. Using Lrig1 knockout models, we show that Lrig1 ablation results in increased aNSCs proliferation with no change in neuronal progeny and that this hyperproliferation likely does not result solely from activation of the epidermal growth factor receptor (EGFR). Loss of LRIG1, however, also leads to impaired activation of transforming growth factor beta (TGFß) and bone morphogenic protein (BMP) signalling. Biochemically, we show that LRIG1 binds TGFß/BMP receptors and the TGFß1 ligand. Finally, we show that the consequences of these interactions are to facilitate SMAD phosphorylation. Collectively, these data suggest that unlike in embryonic NSCs where EGFR may be the primary mechanism of action, in aNSCs, LRIG1 and TGFß pathways function together to fulfill their inhibitory roles.

Utilization and Impact of a Radiation Nursing Clinic to Address Acute Care Needs for Patients with Gynecologic Cancers.

BACKGROUND: The risk factors for acute care utilization in gynecologic oncology patients are poorly understood. This study aimed to evaluate risk factors for the utilization of our centre's acute care radiation nursing clinic (RNC) by gynecologic oncology patients receiving radiotherapy (RT). METHODS: This was a retrospective cohort study of gynecological cancer patients treated with RT at an academic cancer centre between 1 August 2021 and 31 January 2022. Data on socio-demographics, clinical and treatment characteristics, and RNC visits were collected and summarized by descriptive statistics. The Wilcoxon rank sum test and chi-squared test/Fisher's exact test were used for comparisons of continuous and categorical variables, respectively. RESULTS: RT was delivered to 180 patients, of whom 42 (23%) received concurrent chemoradiation (CCR). Compared to those receiving RT alone, patients receiving CCR had higher rates of RNC utilization (55% vs. 19%, p < 0.001). Within the CCR cohort, patients who presented to the RNC were more likely to be unpartnered (43% vs. 11%, p = 0.04), receive a referral to Psychosocial Oncology (39% vs. 5.3%, p = 0.01), and experience treatment interruptions (52% vs. 16%, p = 0.02). There were no associations between RNC visits and age, disease site, or distance from the cancer centre. CONCLUSIONS: The receipt of CCR and specific psychosocial risk factors were associated with increased RNC utilization. Targeted strategies and early intervention to better meet the supportive care and psychosocial needs of this vulnerable population are needed.