Project description:The Adherens Junction protein p120-catenin is implicated in the regulation of cadherin stability, cell migration and inflammatory responses in mammalian epithelial tissues. How these events are coordinated to promote wound repair is not understood. We show that p120-catenin regulates the intrinsic migratory properties or primary mouse keratinocytes, but also influences the migratory behavior of neighboring cells by secreted signals. These events are rooted in the ability of p120-catenin to regulate RhoA-GTPase activity, which leads to a two-tiered control of cell migration. One restrains cell motility via increase of actin stress fibers, reduction in integrin turnover, and an increase in focal adhesions robustness. The other is coupled to the secretion of inflammatory cytokines including Interleukin-24, which causally enhances randomized cell movements. Taken together, our results indicate that p120-RhoA-GTPase-mediated signaling can differentially regulate the migratory behavior of epidermal cells, which has potential implications for chronic wound responses and cancer.
Project description:Pancreatic cancer is one of the most deadly cancers with a 5 year survival rate of about 5%. Therapeutic options are limited, especially for patients that present with late state disease and metastasis. Although the metastatic burden of pancreatic cancer is usually high, little is known about the mechanisms that regulate delamination and dissemination of epithelial cells from preinvasive and malignant pancreatic lesions. Here, we used a preinvasive mouse model of pancreatic cancer to conditionally knockout p120 catenin (Ctnnd1). Mice with biallelic loss of p120 catenin progressively develop high grade PanIN lesions and neoplasia accompanied by prominent acute and chronic inflammatory processes. Loss of p120 catenin in the context of oncogenic Kras also promotes remarkable apical and basal epithelial cell extrusion. Abundant single epithelial cells exit PanIN epithelium basally, survive, and display features of malignancy. Similar extrusion defects are observed following p120 catenin knockdown in vitro, and these effects are completely abrogated by activation of S1P/S1P2 signaling. Our results establish p120 catenin and S1P/S1P2 signaling as novel regulators of non-EMT mediated epithelial cell invasion in pancreatic neoplasia. Transcriptomes of KCiMist1G; p120wt/wt and KCiMist1G; p120f/f pancreases were compared, with three replicates each, using microarray.
Project description:Pancreatic cancer is one of the most deadly cancers with a 5 year survival rate of about 5%. Therapeutic options are limited, especially for patients that present with late state disease and metastasis. Although the metastatic burden of pancreatic cancer is usually high, little is known about the mechanisms that regulate delamination and dissemination of epithelial cells from preinvasive and malignant pancreatic lesions. Here, we used a preinvasive mouse model of pancreatic cancer to conditionally knockout p120 catenin (Ctnnd1). Mice with biallelic loss of p120 catenin progressively develop high grade PanIN lesions and neoplasia accompanied by prominent acute and chronic inflammatory processes. Loss of p120 catenin in the context of oncogenic Kras also promotes remarkable apical and basal epithelial cell extrusion. Abundant single epithelial cells exit PanIN epithelium basally, survive, and display features of malignancy. Similar extrusion defects are observed following p120 catenin knockdown in vitro, and these effects are completely abrogated by activation of S1P/S1P2 signaling. Our results establish p120 catenin and S1P/S1P2 signaling as novel regulators of non-EMT mediated epithelial cell invasion in pancreatic neoplasia.
Project description:Signals emanating from Rho GTPases play pivotal roles in epidermal stem cell homeostasis. However, the agents regulating Rho GTPase output within the epidermal stem cell niche are poorly known. Here, we report that the Rho exchange factor Vav2 regulates the epidermal stem cell transcriptome in an age-dependent manner.
Project description:We report the association of the zonula adherens with a set of mRNAs, through the E-cadherin-p120 catenin binding partner called PLEKHA7.
Project description:ARHGAP35 encoding p190A RhoGAP (p190A) was identified by GWAS as a major human cancer gene. Our published studies have determined that p190A is a tumor suppressor that activates the canonical Hippo pathway. To elucidate how p190A signals in this context, we performed mass spectrometry to identify p190A binding proteins. Two interactors were identified significantly more frequently than others: p120 RasGAP (p120) and ZO-1. Originally p190A was cloned via its direct binding to p120, hence validating our approach. In addition, we found that p190A also binds to ZO-2. The interaction of p190A with ZO-2 is dependent on p120, thus suggesting formation of a ternary complex. Next, we determine that both p120 and ZO-2, but not ZO-1, are necessary for p190A to activate LATS kinases and suppress tumorigenesis in a xenograft mouse model. Moreover, the interactions with p120 and ZO-2 are essential for transcriptional modulation by p190A, including the CDH1 gene encoding E-cadherin, which we previously have demonstrated is essential for p190A signaling. Collectively, this work identifies a novel tumor suppressor interactome of p190A, which includes ZO-2, an established constituent of the Hippo pathway, and p120, which in spite of its strong association with Ras signaling, is essential for p190A to activate LATS kinases.
Project description:Purpose: Presence of pelvic lymph node metastases is the main prognostic factor in early stage cervical cancer patients, primarily treated with surgery. Aim of this study was to identify cellular tumor pathways associated with pelvic lymph node metastasis in early stage cervical cancer. Experimental Design: Gene expression profiles (Affymetrix U133 plus 2.0) of 20 patients with negative (N0) and 19 with positive lymph nodes (N+), were compared with gene sets that represent all 285 presently available pathway signatures. Validation immunostaining of tumors of 274 consecutive early stage cervical cancer patients was performed for representatives of the identified pathways. Results: Analysis of 285 pathways resulted in identification of five pathways (TGF-β, NFAT, ALK, BAD, and PAR1) that were dysregulated in the N0, and two pathways (β-catenin and Glycosphingolipid Biosynthesis Neo Lactoseries) in the N+ group. Class comparison analysis revealed that five of 149 genes that were most significantly differentially expressed between N0 and N+ tumors (P<0.001) were involved in β-catenin signaling (TCF4, CTNNAL1, CTNND1/p120, DKK3 and WNT5a). Immunohistochemical validation of two well-known cellular tumor pathways (TGF-β and β-catenin) confirmed that the TGF-β pathway (positivity of Smad4) was related to N0 (OR:0.20, 95%CI:0.06-0.66) and the β-catenin pathway (p120 positivity) to N+ (OR:1.79, 95%CI:1.05-3.05). Conclusions: Our study provides new, validated insights in the molecular mechanism of lymph node metastasis in cervical cancer. Pathway analysis of the microarray expression profile suggested that the TGF-β and p120-associated non-canonical β-catenin pathways are important in pelvic lymph node metastasis in early stage cervical cancer. For the microarray experiment, we selected fresh frozen primary cervical cancer tissue, containing at least 80% tumor cells, of patients with histologically confirmed N0 (n=20) and of patients with N+ (n=19). The N0 and N+ groups were matched for age, FIGO stage and histology (all squamous cell carcinoma).
Project description:Purpose: Presence of pelvic lymph node metastases is the main prognostic factor in early stage cervical cancer patients, primarily treated with surgery. Aim of this study was to identify cellular tumor pathways associated with pelvic lymph node metastasis in early stage cervical cancer. Experimental Design: Gene expression profiles (Affymetrix U133 plus 2.0) of 20 patients with negative (N0) and 19 with positive lymph nodes (N+), were compared with gene sets that represent all 285 presently available pathway signatures. Validation immunostaining of tumors of 274 consecutive early stage cervical cancer patients was performed for representatives of the identified pathways. Results: Analysis of 285 pathways resulted in identification of five pathways (TGF-β, NFAT, ALK, BAD, and PAR1) that were dysregulated in the N0, and two pathways (β-catenin and Glycosphingolipid Biosynthesis Neo Lactoseries) in the N+ group. Class comparison analysis revealed that five of 149 genes that were most significantly differentially expressed between N0 and N+ tumors (P<0.001) were involved in β-catenin signaling (TCF4, CTNNAL1, CTNND1/p120, DKK3 and WNT5a). Immunohistochemical validation of two well-known cellular tumor pathways (TGF-β and β-catenin) confirmed that the TGF-β pathway (positivity of Smad4) was related to N0 (OR:0.20, 95%CI:0.06-0.66) and the β-catenin pathway (p120 positivity) to N+ (OR:1.79, 95%CI:1.05-3.05). Conclusions: Our study provides new, validated insights in the molecular mechanism of lymph node metastasis in cervical cancer. Pathway analysis of the microarray expression profile suggested that the TGF-β and p120-associated non-canonical β-catenin pathways are important in pelvic lymph node metastasis in early stage cervical cancer.