Introduction

Our research is focusing on the identification and molecular characterisation of stem cell intrinsic mechanisms that guarantee normal stem cell function required maintaining and regenerating epithelial tissues. We further investigate how abnormal stem cell responses contribute to disease formation, including cancer initiation and progression.

Stem cell-specific surveillance mechanisms

Recent studies have indicated that epidermal stem cells, which are crucial for maintaining skin homeostasis, respond differently to stress and DNA damage compared to their rapidly cycling progeny. Hair follicle bulge stem cells possess stem cell-specific surveillance mechanisms regulating the DNA damage response. In particular, multipotent hair follicle stem cells are more resistant to DNA-damage-induced cell death, which has been linked to a higher expression of pro-survival factors and attenuated activation of tumour suppressor molecules, such as p53. We are investigating the relevance of these stem cell-specific gatekeeper functions for the process of disease initiation. More specifically, we decipher the molecular network of gatekeeper activation and responses and explore mechanisms to control crucial stem cell-specific surveillance mechanisms to prevent tumour formation.

Determination of stem cell fate and function

Mammalian skin, the protective covering of the body, consists of specialised epithelial compartments, including the interfollicular epidermis and its appendages, the hair follicles, sebaceous and sweat glands. The formation of epidermal appendages involves an ordered set of developmental processes beginning with expansion of undifferentiated stem and progenitor cells followed by lineage commitment of progenitor cells and the subsequent differentiation of their progeny. Our research aims to unravel how lineage specification of stem cells is regulated during tissue morphogenesis, a process that is crucial for the establishment of proper tissue morphology and function.
The lab has a long-standing interest in identifying basic cellular and molecular mechanisms governing the process of cell lineage specification in mammalian skin. In particular, our work dissects the function of canonical Wnt/β-catenin/Lef1 signalling activity and the role of a Hedgehog-Gli2 signalling axis in tissue homeostasis and cancer.

To address these important issues we use a combination of state of the art molecular and cellular biology techniques, primary cell culture (human and and mouse), conditional mouse models, confocal microscopy as well as high-throughput genomic approaches.

Lab Website

For further information please check the Niemann Laboratory for Stem cell and cancer biology's webpage.

  • Geueke A, Mantellato G, Kuester F, Schettina P, Nelles M, Seeger JM, Kashkar H, and Niemann C (2021). The anti-apoptotic Bcl-2 protein regulates hair follicle stem cell function. EMBO Rep22, e52301. doi:10.15252/embr.202052301.
                                                                                                                                                                                                                                                                              • Tayem R, Niemann C, Pesch M, Morgner J, Niessen CM, Wickstrom SA, and Aumailley M (2021). Laminin 332 Is Indispensable for Homeostatic Epidermal Differentiation Programs. J Invest Dermatol141, 2602-2610 e2603. doi:10.1016/j.jid.2021.04.008.
                                                                                                                                                                                                                                                                              • Geueke A, and Niemann C (2021). Stem and progenitor cells in sebaceous gland development, homeostasis and pathologies. Exp Dermatol30, 588-597. doi:10.1111/exd.14303.
                                                                                                                                                                                                                                                                              • Sanchez-Ruiz M, Iorgu AM, Küster F, Hellmich M, Brunn A, and Deckert M (2021). CD8 T cell-Derived Perforin and TNF-a Are Crucial Mediators of Neuronal Destruction in Experimental Autoimmune Enteric Ganglionitis. Am J Pathol191, 1064-1074. doi:10.1016/j.ajpath.2021.02.021.
                                                                                                                                                                                                                                                                              PD Dr. Catherin Niemann
                                                                                                                                                                                                                                                                              PD Dr. Catherin Niemann

                                                                                                                                                                                                                                                                              CMMC Cologne | Institute of Biochemistry | CMMC Research Building

                                                                                                                                                                                                                                                                              CMMC - PI - assoc. RG 14
                                                                                                                                                                                                                                                                              IPMM Program - Scientific Coordinator I CMMC Tissue Embedding and Histology & Microscopy - Head

                                                                                                                                                                                                                                                                              CMMC Cologne | Institute of Biochemistry | CMMC Research Building

                                                                                                                                                                                                                                                                              Robert-Koch-Str. 21

                                                                                                                                                                                                                                                                              50931 Cologne

                                                                                                                                                                                                                                                                              Publications - Catherin Niemann

                                                                                                                                                                                                                                                                              Link to PubMed