Rapid Crypt Cell Remodeling Regenerates the Intestinal Stem Cell Niche after Notch Inhibition
STEM CELL REPORTS
Authors: Bohin, Natacha; Keeley, Theresa M.; Carulli, Alexis J.; Walker, Emily M.; Carlson, Elizabeth A.; Gao, Jie; Aifantis, Iannis; Siebel, Christian W.; Rajala, Michael W.; Myers, Martin G., Jr.; Jones, Jennifer C.; Brindley, Constance D.; Dempsey, Peter J.; Samuelson, Linda C.
Abstract
Intestinal crypts have great capacity for repair and regeneration after intestinal stem cell (ISC) injury. Here, we define the cellular remodeling process resulting from ISC niche interruption by transient Notch pathway inhibition in adult mice. Although ISCs were retained, lineage tracing demonstrated a marked reduction in ISC function after Notch disruption. Surprisingly, Notch ligand-expressing Paneth cells were rapidly lost by apoptotic cell death. The ISC-Paneth cell changes were followed by a regenerative response, characterized by expansion of cells expressing Notch ligands Dll1 and Dll4, enhanced Notch signaling, and a proliferative surge. Lineage tracing and organoid studies showed that Dll1-expressing cells were activated to function as multipotential progenitors, generating both absorptive and secretory cells and replenishing the vacant Paneth cell pool. Our analysis uncovered a dynamic, multicellular remodeling response to acute Notch inhibition to repair the niche and restore homeostasis. Notably, this crypt regenerative response did not require ISC loss.
DLL4 as a predictor of pelvic lymph node metastasis and a novel prognostic biomarker in patients with early-stage cervical cancer
TUMOR BIOLOGY
Authors: Yang, Shanshan; Liu, YunDuo; Xia, BaiRong; Deng, Jiangpeng; Liu, TianBo; Li, Qi; Yang, YanPing; Wang, YaoXian; Ning, XiaoMing; Zhang, YunYan; Xiao, Min
Abstract
Delta-like ligand 4 (DLL4), one of the five Notch signaling ligands in mammals, has an important function in proliferation, invasion, metastasis, progression, and angiogenesis of malignancies. This study aimed to investigate DLL4 expression level in early-stage cervical carcinoma and to evaluate its clinical significance. We used fresh frozen and paraffin-embedded cervical cancer tissues to analyze DLL4 expression and its clinical significance. DLL4 expression at both mRNA and protein levels in cervical cancer tissues was significantly higher than that in normal cervical tissues. High DLL4 protein level was clearly correlated with high International Federation of Gynecology and Obstetrics (FIGO) stage (P = 0.044), lymphovascular space involvement (LVSI) (P = 0.015), pelvic lymph node metastasis (PLNM) (P = 0.001), and recurrence (P < 0.001). Univariate and multivariate logistic regression analyses demonstrated that DLL4 overexpression was strongly associated with lymph node metastasis (odds ratio, 2.790; 95 % CI, 1.344-5.791; P = 0.006). Moreover, survival analysis revealed that DLL4 expression was an independent factor of unfavorable overall survival (hazard ratio, 2.130; 95 % CI, 1.108-4.097; P = 0.023) and disease-free survival (hazard ratio, 1.965; 95 % CI, 1.085-3.560; P = 0.026) in patients with cervical cancer. Overall, our data indicate that high DLL4 expression predicts pelvic lymph node metastasis and poor survival in cervical cancer. Therefore, DLL4 may be a potential clinical diagnostic marker for patients with early-stage cervical cancer.