Projects
The Hedgehog-GLI (HH-GLI) signalling pathway is an important regulator of embryonic development, while it is mostly inactive in the adult organism. It only remains active in somatic stem cells. Aberrant activation of the pathway contributes to tumorigenesis in many tumor types. The GLI1, GLI2 and GLI3 transcription factors regulate gene expression of targets involved in proliferation, metastasis and cancer stem cell renewal. In our previous research we were the first to analyse the transcriptomes of all three GLI proteins in melanoma, and we have identified a large number of target genes, some of them previously known from literature data, but also some novel.
The Hedgehog-GLI (HH-GLI) signalling pathway is an important regulator of embryonic development, while it is mostly inactive in the adult organism. It only remains active in somatic stem cells. Aberrant activation of the pathway contributes to tumorigenesis in many tumor types. The GLI1, GLI2 and GLI3 transcription factors regulate gene expression of targets involved in proliferation, metastasis and cancer stem cell renewal. In our previous research we were the first to analyse the transcriptomes of all three GLI proteins in melanoma, and we have identified a large number of target genes, some of them previously known from literature data, but also some novel.
In this project, we wish to investigate:
- which growth factors are directly regulated by HH-GLI signalling on cell models of ovarian, prostate and head and neck cancers,
- how are the signals transmitted between cells,
- how do the growth factors affect tumor and stromal cells,
- does the ratio of tumor to stromal cells affect gene expression in the two populations,
- what is the effect of HH-GLI and growth factor inhibition (individually or combined) on both populations in vitro.
To answer these questions, we will use cell culture models. The cells will be grown in 2D, but also in 3D cultures, as spheroids. In both setups, co-culture of tumor and stromal cells will be used as well. The results from the first three years of the project will then be validated on patient-derived archive material: tumor RNA, paraffin-embedded tissue slides and primary cell cultures of both tumor and stromal origin. We will be using many standard molecular biology techniques (qPCR, Western blot, immunofluorescence), but also some advanced techniques such as protein antibody arrays, RNA-seq and live cell imaging.
With this project we will demonstrate the role of HH-GLI signalling in tumor-stroma communication, which could lead to advances in combined tumor therapy and to discovery of new prognostic markers.
HHgrow3D - The role of Hedgehog-GLI signaling in growth factor-mediated tumor-stroma communication in 2D and 3D in vitro tumor models
The Hedgehog-GLI (HH-GLI) signalling pathway is an important regulator of embryonic development, while it is mostly inactive in the adult organism. It only remains active in somatic stem cells. Aberrant activation of the pathway contributes to tumorigenesis in many tumor types. The GLI1, GLI2 and GLI3 transcription factors regulate gene expression of targets involved in proliferation, metastasis and cancer stem cell renewal. In our previous research we were the first to analyse the transcriptomes of all three GLI proteins in melanoma, and we have identified a large number of target genes, some of them previously known from literature data, but also some novel.
GLIcode - Differential regulation of the GLI code in BRAF/NRAS driven tumors
The Hedgehog signaling pathway has been implicated in development of various tumors, but the exact roles and molecular mechanisms are still not understood. The focus of this research are the tumors harboring BRAF or NRAS mutations, and their differential response to Hedgehog pathway inhibition. Both BRAF and NRAS non-canonically activate the three GLI proteins, but the activity and interplay of this interaction is still unclear. With this project we propose to determine the exact transcriptional targets of GLI1, GLI2 and GLI3 proteins in melanoma with different genetic backgrounds, either harboring a BRAF mutation, a NRAS mutation, or no mutation in these two genes.
MIRnaGLI - Novel Molecular Mechanisms for New Therapeutic Approaches: Interactions of microRNAs and Hedgehog-GLI Signaling Pathway in Serous Ovarian Carcinoma
Serous ovarian cancer is urgent clinical problem whose molecular background is still unknown. Our previous studies showed aberrant activity of the Hedgehog-GLI (Hh-Gli) signaling pathway in ovarian tumors, but we have shown that aberrant activity is neither the result of mutations nor of promoter hypermethylation of the main pathway regulators. The next to study are microRNAs (miRNAs), one of the main regulators in post-transcriptional regulation of gene expression. Our hypothesis is that changes in the expression of miRNA molecules related to the Hh-Gli signaling pathway contribute to the development of high-grade serous ovarian cancer.
ProNetMel - New Protein Networks for Novel Therapeutic Avenues in Human Melanoma
The main focus of this project is to reveal interactions of p53 with protein partners in melanoma that are capable of modifying its function. We are particularly interested in possible interactions of p53 with family members, namely p53 and p73 isoforms, with nm23, especially nm23-H1 and nm23-H2, and Gli family of proteins.