Proc Natl Acad Sci U S A.
Spermatogonial stem cells (SSCs) fuel the production of male germ cells but the mechanisms behind SSC self-renewal, proliferation, and differentiation are still poorly understood. Using the Wnt target gene Axin2 and genetic lineage-tracing experiments, we found that undifferentiated spermatogonia, comprising SSCs and transit amplifying progenitor cells, respond to Wnt/β-catenin signals. Genetic elimination of β-catenin indicates that Wnt/β-catenin signaling promotes the proliferation of these cells. Signaling is likely initiated by Wnt6, which is uniquely expressed by neighboring Sertoli cells, the only somatic cells in the seminiferous tubule that support germ cells and act as a niche for SSCs. Therefore, unlike other stem cell systems where Wnt/β-catenin signaling is implicated in self-renewal, the Wnt pathway in the testis specifically contributes to the proliferation of SSCs and progenitor cells.
Abdou, Y;Barton, D;Ronczka, A;Cushing, D;Klichinsky, M;Binder, K;
| DOI: 10.1158/1538-7445.sabcs21-ot1-03-01
Adoptive T cell therapies have led to remarkable advances among patients with hematologic malignancies, but not in those with solid tumors. Macrophages are actively recruited into, and abundantly present in the solid tumor microenvironment (sTME). Tumor- associated macrophages typically evince immunosuppressive behavior, but when engineered to be proinflammatory, may be an ideal vector to administer adoptive cellular therapy in solid tumors. Furthermore, insertion of a CAR on the macrophages confers the ability to selectively recognize and phagocytose antigen overexpressing cancer cells. Additionally, CAR macrophages reprogram the sTME and present neoantigens to T cells, leading to epitope spreading and immune memory. Human Epidermal Growth Factor Receptor 2 (HER2) overexpression promotes tumorigenesis and is seen in many cancers, including but not limited to breast and gastroesophageal cancers (Table 1). CT-0508 is a cell product comprised of autologous monocyte-derived pro-inflammatory macrophages expressing an anti-HER2 CAR. Pre-clinical studies have shown that CT-0508 induced targeted cancer cell phagocytosis while sparing normal cells, decreasing tumor burden and prolonging survival in relevant models. CT-0508 cells were safe and effective in a semi-immunocompetent mouse model of human HER2 overexpressing ovarian cancer. This is a FIH Phase 1 study to evaluate safety, tolerability, cell manufacturing feasibility, trafficking, and preliminary evidence of efficacy of investigational product CT-0508 in approximately 18 subjects with locally advanced (unresectable) or metastatic solid tumors overexpressing HER2, who have failed available therapies including anti-HER2 therapies where indicated.Filgrastim is being used to mobilize autologous hematopoietic progenitor cells for monocyte collection by apheresis. The CT-0508 CAR macrophage product is manufactured, prepared and cryopreserved from mobilized peripheral blood monocytes. The study is enrolling Group 1 subjects, who receive CT-0508 infusion split over D1, 3 and 5. Subjects will be continually assessed for acute and cumulative toxicity. Dose limiting toxicities will be observed and addressed by a Safety Review Committee. Group 2 subjects will follow, and will receive the full CT-0508 infusion on D1. Pre and post treatment biopsies and blood samples will be collected to investigate correlates of safety (immunogenicity), trafficking (PCR, RNA scope), CT-0508 persistence in blood and in the tumor, target antigen engagement, TME modulation (single cell RNA sequencing), immune response (TCR sequencing) and others. Clinical trial registry number: NCT04660929 Table 1.HER2 Positivity Frequencies Across Tumor TypesTumor typeHER2 positivity (%)ReferenceBladder cancer8-70Gandour-Edwards et al, 2002;Caner et al, 2008;Laé et al, 2010; Fleischmann et al, 2011;Charfi et al, 2013;Yan et al, 2015Breast cancer11.0-25.0Varga et al, 2013;Stenehjem et al, 2014Cervical cancer2.8-3.9Chavez-Blanco et al, 2004;Yan et al, 2015Colorectal cancer1.6-5.0Schuell et al, 2006;Ingold Heppner et al, 2014;Seo et al, 2014Esophageal cancer12.0-14.0König et al, 2013;Yoon et al, 2013;Wang et al, 2014Extrahepatic Cholangiocarcinoma6.3-9.0Yoshikawa et al, 2008;Yan et al, 2015Gallbladder cancer9.8-12.8Roa et al, 2014;Yan et al, 2015Gastric adenocarcinoma7.0-34.0Rüschoff et al, 2012;Hofmann et al, 2008Ovarian cancer26Slamon et al, 1989Salivary mucoepidermoid carcinomas17.6Glisson et al, 2004Salivary duct carcinoma30-40Skálová et al, 2003; Cornolti et al, 2007; Nardi et al, 2013Testicular cancer2.4Yan et al, 2015Uterine cancer3.0Yan et al, 2015 Citation Format: Yara George Abdou, Debora Barton, Amy Ronczka, Daniel Cushing, Michael Klichinsky, Kim Reiss Binder. A phase 1, first in human (FIH) study of adenovirally transduced autologous macrophages engineered to contain an anti-HER2 chimeric antigen receptor (CAR) in subjects with HER2 overexpressing solid tumors [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT1-03-01.
Abstract CT204: A phase 1, first in human (FIH) study of adenovirally transduced autologous macrophages engineered to contain an anti-HER2 chimeric antigen receptor (CAR) in subjects with HER2 overexpressing solid tumors
Bauml, J;Barton, D;Ronczka, A;Cushing, D;Klichinsky, M;Dees, E;
| DOI: 10.1158/1538-7445.am2021-ct204
Background: Adoptive T cell therapies have led to remarkable advances among patients with hematologic malignancies, but not in those with solid tumors. Macrophages are actively recruited into, and abundantly present in the solid tumor microenvironment (sTME). Tumor- associated macrophages typically evince immunosuppressive behavior, but when engineered to be proinflammatory, may be an ideal vector to administer adoptive cellular therapy in solid tumors. Furthermore, insertion of a CAR confers on the macrophages the ability to selectively recognize and phagocytose antigen overexpressing cancer cells. Additionally, CAR macrophages reprogram the sTME and present neoantigens to T cells, leading to epitope spreading and immune memory. Human Epidermal Growth Factor Receptor 2 (HER2) is overexpressed in many cancers, including but not limited to breast and gastroesophageal cancers. CT-0508 is a cell product comprised of autologous monocyte-derived pro-inflammatory macrophages expressing an anti-HER2 CAR. Pre-clinical studies have shown that CT-0508 induced targeted cancer cell phagocytosis while sparing normal cells, decreased tumor burden and prolonged survival in relevant models. CT-0508 cells were safe in a semi-immunocompetent mouse model of human HER2 overexpressing ovarian cancer. Methods: This is a FIH Phase 1 study to evaluate safety, tolerability, cell manufacturing feasibility, trafficking, and preliminary evidence of efficacy of investigational product CT-0508 in approximately 18 subjects with locally advanced (unresectable) or metastatic solid tumors overexpressing HER2 who have failed available therapies including anti-HER2 therapies when indicated. Filgrastim will be used to mobilize autologous hematopoietic progenitor cells for monocyte collection by apheresis. The CT-0508 CAR macrophage product will be manufactured, prepared and cryopreserved from mobilized peripheral blood monocytes. Group 1 subjects will receive CT-0508 infusion split over D1, 3 and 5. Subjects will be continually assessed for acute and cumulative toxicity. Dose limiting toxicities will be observed and addressed by a Safety Review Committee. Group 2 subjects will receive the full CT-0508 infusion on D1. Pre and post treatment biopsies and blood samples will be collected to investigate correlates of safety (immunogenicity), trafficking (PCR, RNA scope), persistence, target antigen engagement, TME modulation (single cell RNA sequencing), immune response (TCR sequencing) and others.
Proc Natl Acad Sci U S A.
Lim X, Tan SH, Yu KL, Lim SB, Nusse R.
PMID: 26903625 | DOI: -
How stem cells maintain their identity and potency as tissues change during growth is not well understood. In mammalian hair, it is unclear how hair follicle stem cells can enter an extended period of quiescence during the resting phase but retain stem cell potential and be subsequently activated for growth. Here, we use lineage tracing and gene expression mapping to show that the Wnt target gene Axin2 is constantly expressed throughout the hair cycle quiescent phase in outer bulge stem cells that produce their own Wnt signals. Ablating Wnt signaling in the bulge cells causes them to lose their stem cell potency to contribute to hair growth and undergo premature differentiation instead. Bulge cells express secreted Wnt inhibitors, including Dickkopf (Dkk) and secreted frizzled-related protein 1 (Sfrp1). However, the Dickkopf 3 (Dkk3) protein becomes localized to the Wnt-inactive inner bulge that contains differentiated cells. We find that Axin2 expression remains confined to the outer bulge, whereas Dkk3 continues to be localized to the inner bulge during the hair cycle growth phase. Our data suggest that autocrine Wnt signaling in the outer bulge maintains stem cell potency throughout hair cycle quiescence and growth, whereas paracrine Wnt inhibition of inner bulge cells reinforces differentiation.
Sulic, AM;Das Roy, R;Papagno, V;Lan, Q;Saikkonen, R;Jernvall, J;Thesleff, I;Mikkola, ML;
PMID: 37318953 | DOI: 10.1016/j.celrep.2023.112643
Morphogenesis of ectodermal organs, such as hair, tooth, and mammary gland, starts with the formation of local epithelial thickenings, or placodes, but it remains to be determined how distinct cell types and differentiation programs are established during ontogeny. Here, we use bulk and single-cell transcriptomics and pseudotime modeling to address these questions in developing hair follicles and epidermis and produce a comprehensive transcriptomic profile of cellular populations in the hair placode and interplacodal epithelium. We report previously unknown cell populations and marker genes, including early suprabasal and genuine interfollicular basal markers, and propose the identity of suprabasal progenitors. By uncovering four different hair placode cell populations organized in three spatially distinct areas, with fine gene expression gradients between them, we posit early biases in cell fate establishment. This work is accompanied by a readily accessible online tool to stimulate further research on skin appendages and their progenitors.
PLoS One. 2014 Jun 26;9(6):e99131.
Vassilakopoulou M, Togun T, Dafni U, Cheng H1, Bordeaux J, Neumeister VM, Bobos M, Pentheroudakis G, Skarlos DV, Pectasides D, Kotoula V, Fountzilas G, Rimm DL, Psyrri A.
PMID: 24968015 | DOI: 10.1371/journal.pone.0099131.eCollection2014.
BACKGROUND: We sought to determine the predictive value of in situ mRNA measurement compared to traditional methods on a cohort of trastuzumab-treated metastatic breast cancer patients. METHODS: A tissue microarray composed of 149, classified as HER2-positive, metastatic breast cancers treated with various trastuzumab-containing chemotherapy regimens was constructed. HER2 intracellular domain(ICD), HER2 extracellular domain(ECD) and HER2 mRNA were assessed using AQUA. For HER2 protein evaluation, CB11 was used to measure ICD and SP3 to measure ECD of the HER2 receptor. In addition, HER2 mRNA status was assessed using RNAscope assay ERRB2 probe. Kaplan - Meier estimates were used for depicting time-to-event endpoints. Multivariate Cox regression models with backward elimination were used to assess the performance of markers as predictors of TTP and OS, after adjusting for important covariates. RESULTS: HER2 mRNA was correlated with ICD HER2, as measured by CB11 HER2, with ECD HER2 as measured by SP3 (Pearson's Correlation Coefficient, r = 0.66 and 0.51 respectively) and with FISH HER2 (Spearman's Correlation Coefficient, r = 0.75). All markers, HER2 mRNA, ICD HER2 and ECD HER2, along with FISH HER2, were found prognostic for OS (Log-rank p = 0.007, 0.005, 0.009 and 0.043 respectively), and except for FISH HER2, they were also prognostic for TTP Log-rank p = 0.036, 0.068 and 0.066 respectively) in this trastuzumab- treated cohort. Multivariate analysis showed that in the presence of pre-specified set of prognostic factors, among all biomarkers only ECD HER2, as measured by SP3, is strong prognostic factor for both TTP (HR = 0.54, 95% CI: 0.31-0.93, p = 0.027) and OS (HR = 0.39, 95%CI: 0.22-0.70, p = 0.002). CONCLUSIONS: The expression of HER2 ICD and ECD as well as HER2 mRNA levels was significantly associated with TTP and OS in this trastuzumab-treated metastatic cohort. In situ assessment of HER2 mRNA has the potential to identify breast cancer patients who derive benefit from Trastuzumab treatment.
New Biotechnology, 29(6), 665–681.
Portier BP, Gruver AM, Huba MA, Minca EC, Cheah AL, Wang Z, Tubbs RR (2012).
PMID: 22504737 | DOI: 10.1016/j.nbt.2012.03.011.
Diagnostics in the field of breast carcinoma are constantly evolving. The recent wave of molecular methodologies, both microscope and non-microscope based, have opened new ways to gain insight into this disease process and have moved clinical diagnostics closer to a 'personalized medicine' approach. In this review we highlight some of the advancements that laboratory medicine technology is making toward guiding the diagnosis, prognosis, and therapy selection for patients affected by breast carcinoma. The content of the article is largely structured by methodology, with a distinct emphasis on both microscope based and non-microscope based diagnostic formats. Where possible, we have attempted to emphasize the potential benefits as well as limitations to each of these technologies. Successful molecular diagnostics, applied in concert within the morphologic context of a patient's tumor, are what will lay the foundation for personalized therapy and allow a more sophisticated approach to clinical trial stratification. The future of breast cancer diagnostics looks challenging, but it is also a field of great opportunity. Never before have there been such a plethora of new tools available for disease investigation or candidate therapy selection.
Am J Clin Pathol. 2018 Oct 18.
Gibbons-Fideler IS, Nitta H, Murillo A, Tozbikian G, Banks P, Parwani AV, Li Z.
PMID: 30339245 | DOI: 10.1093/ajcp/aqy136
OBJECTIVES:
Either immunohistochemistry (IHC) or in situ hybridization (ISH) can be used to determine human epidermal growth factor receptor 2 (HER2) status. Breast cancers (BCs) with HER2 IHC-negative (IHC-) and ISH-amplified (ISH+) results have been rarely reported but not well studied. We investigated the frequency of HER2 IHC-/ISH+ BCs and their response to anti-HER2 neoadjuvant chemotherapy (NAC).
METHODS:
Seventeen BCs with HER2 IHC-/ISH+ results were identified from 1,107 consecutive invasive BCs (1.5%, 17/1,107).
RESULTS:
Gene protein assay confirmed the original HER2 IHC and ISH results. Increased HER2 RNA level was detected in HER2 IHC-/ISH+ cases compared with HER2 IHC-/ISH- cases. Eight patients had anti-HER2 NAC; three had pathologic complete response, and five had residual tumors.
CONCLUSIONS:
A small percentage of patients (1.5%) showed discordant HER2 IHC and ISH results (IHC-/ISH+) and would have lost the opportunity for potentially beneficial anti-HER2-targeted therapy if only HER2 IHC testing had been used."
Sigal M, Logan CY, Kapalczynska M, Mollenkopf HJ, Berger H, Wiedenmann B, Nusse R, Amieva MR, Meyer TF.
PMID: 28813421 | DOI: 10.1038/nature23642
The constant regeneration of stomach epithelium is driven by long-lived stem cells, but the mechanism that regulates their turnover is not well understood. We have recently found that the gastric pathogen Helicobacter pylori can activate gastric stem cells and increase epithelial turnover, while Wnt signalling is known to be important for stem cell identity and epithelial regeneration in several tissues. Here we find that antral Wnt signalling, marked by the classic Wnt target gene Axin2, is limited to the base and lower isthmus of gastric glands, where the stem cells reside. Axin2 is expressed by Lgr5+ cells, as well as adjacent, highly proliferative Lgr5- cells that are able to repopulate entire glands, including the base, upon depletion of the Lgr5+ population. Expression of both Axin2 and Lgr5 requires stroma-derived R-spondin 3 produced by gastric myofibroblasts proximal to the stem cell compartment. Exogenous R-spondin administration expands and accelerates proliferation of Axin2+/Lgr5- but not Lgr5+ cells. Consistent with these observations, H. pylori infection increases stromal R-spondin 3 expression and expands the Axin2+ cell pool to cause hyperproliferation and gland hyperplasia. The ability of stromal niche cells to control and adapt epithelial stem cell dynamics constitutes a sophisticated mechanism that orchestrates epithelial regeneration and maintenance of tissue integrity.