Univ.-Prof. Dr. med. Hans Christian Reinhardt

Research Area: DNA damage responses in Aging-associated Diseases

Website:  http://reinhardt.cecad-labs.uni-koeln.de

1. Research Background:

Cancer is a genetic disease. Throughout the last decade, we have witnessed the emergence of novel DNA- and RNA- sequencing technologies, which allow an unprecedented glimpse at the complexity of genomic aberrations that underlie the process of malignant transformation. This novel understanding of cancer biology is shifting our therapeutic approaches away from non-selective genotoxic therapy and towards molecularly-guided therapeutic interventions. In this context, defects in the DNA damage response and cell cycle control are of key importance. On the one hand, they can accelerate the progression of cancer to more malignant states, but on the other hand, we and many others have shown that they generate specific weaknesses that can be successfully exploited to design molecularly-guided therapies.

2. Research questions addresses by the group:

The aim of our laboratory is the development of novel therapeutic approaches for cancer patients, with a special focus on lung cancer and lymphoid neoplasms. To achieve this goal, we have set up a platform for in vitro pharmaco-genomics screening composed of approximately 350 distinct human cancer cell lines, each representing a different cancer genome and each with well annotated genetic, epigenetic and expression profiles. In addition, we have collected a wide array of genetically engineered mouse models, which mimic many of the common genetic defects found in human cancer, such as loss of Trp53, Atm, and Msh3. We use forward genetics screens to identify the genetic determinants of cancer progression, metastatic spread, response to therapy and development of resistance. In parallel, we use pharmaco-genomics screens to identify novel synergistic combinations of drugs and test the results in preclinical mouse models. For example, we have identified DNA-PKcs inhibitors as a synergystic therapeutic option in homologous recombination-deficient cancers and the combination of Chk1- and MK2 inhibitors as a specific therapy in KRAS- or BRAF-mutant cells. Through collaborations with colleagues from the clinical departments, we also strive to translate our preclinical results into clinical studies and clinical practice.

3. Possible projects:

Possible projects for PhD students will focus on the tumorigenesis, progression and response to therapy of small cell lung cancer (SCLC) using the Tp53fl/fl;Rb1fl/fl mouse model (RP), which mimics the most common genetic alterations in human SCLC (loss of TP53 and loss of RB1) and has been shown to faithfully reproduce histological and clinical features of human SCLC. In vivo forward genetics experiments with the PiggyBac transposon system and in silico analysis of large, openly available databases will be used to identify novel genetic determinants of tumorigenesis and metastatic spread, novel predictors of response to therapy and novel mutations leading to the development of resistance to therapy. Different genetically engineered DNA damage-response-deficient and progeroid mouse lines will be used to investigate the effects of specific DNA-repair defects on the onset, progression and response to therapy of SCLC. Cell culture studies using both our collection of human cancer lines and cell lines derived from RP mice will be used to further clarify the mechanisms of cancer progression and response to therapy.

Guided by the results of the initial screens, different therapeutic strategies aimed at the intrinsic vulnerabilities of cancer cells will be tested in vitro and in vivo. For example, given the loss of RB1 and TP53, two key regulators of the cell cycle under normal conditions and after genotoxic damage, we will test the combination of different cell cycle checkpoints inhibitors and genotoxic agents.

4. Applied Methods and model organisms:

The main model used will be the Tp53fl/fl;Rb1fl/fl mouse, in which gene inactivation is achieved through intrateacheal application of AdenoCre, which causes recombination only in the lung. We have crossed the RP mouse with mouse lines carrying the PiggyBac transposase and different transposons to allow for forward insertional mutagenesis screens. Additional genetically engineered mouse lines, harboring mutations in different cancer-related and DNA damage-response genes, such as Ercc1, Msh2, and Blm, will be crossed into the RP line to mimic the genotoxic smoking signature that is commonly observed in patients to ultimately evaluate the effects of different specific DNA-repair defects in the pathogenesis of SCLC. The detailed characterization of these lines will include the generation of survival curves, the extraction of organs for tissue stainings and the generation of MEFs and tumor cell lines.

In addition to the forward PB screening, we will use computational analysis of omics data, such as whole-genome sequencing and RNA-seq both derived from our own samples and contained within large, openly-available databases, such as the cancer genome atlas (TCGA) to identify novel therapeutic targets.

A wide array of molecular biology methods, such as FACS, immunofluorescence, immunoblotting and q-PCR will be used in cell culture experiments to investigate the precise mechanisms leading from the genetic defects to the various stages of cancer progression and response to therapy.

Novel therapeutic strategies will be tested using our collection of cancer cell lines and genetically engineered mouse lines.

5. Desirable skills and qualifications:

We seek highly motivated students with a strong interest in cancer research. Desired qualities are:

  • Previous experience or interest in the use of the mouse as an experimental model
  • Fluent English
  • A strong aptitude for teamwork
  • Previous experience or interest in computational biology

6. References:

  • Schmitt et al. ATM deficiency is associated with sensitivity to PARP1 and ATR inhibitors in lung adenocarcinoma, Cancer Research, 2017
  • Knittel G et at. Two mouse models reveal an actionable PARP1 dependence in aggressive chronic lymphocytic leukemia. Nature Communications, 2017
  • Jokić M, Vlašić I, Rinneburger M, et al. Ercc1 Deficiency Promotes Tumorigenesis and Increases Cisplatin Sensitivity in a TP53 Context-specific Manner. Molecular Cancer Research, 2016
  • Knittel G et al. B cell-specific conditional expression of Myd88p.L252P leads to the development of diffuse large B cell lymphoma in mice. Blood, 2016
  • George J et al. Comprehensive genomic profiling of small cell lung cancer. Nature, 2015
  • Dietlein F et al. A synergistic interaction between Chk1- and MK2 inhibitors in KRAS-mutant cancer. Cell, 2015