#JournalClub with Shreya: Modelling Brain Tumour Spread

This article by Krieger et al. discusses the most common form of brain cancer called glioblastoma. Due to its highly aggressive nature, research must be conducted consistently and rapidly to develop new treatments. This has proven challenging due to primary tumours being resected before further research can be done, as well as the lack of current technologies to fully explore relationships between GBM and surrounding brain tissues. This study aimed to study the aforementioned interactions in under 4 weeks, accounting for the rapid progression of the disease in real life.  

GBM cells were first derived from four patients and treated with glutamine, heparin, epidermal and fibroblast growth factors, then underwent a sequence of manipulations, such as second-generation replication lentivirus infection of GBM cells, iPSC line 409b2 inoculation in Aggrewell plates and later manipulation with invasion assays, and scRNA sequencing, which, along with the Aggrewell cells, produced neural progenitor cell spheroids for analysis. Confocal microscopy and the developed image processing algorithm allowed for visualization of these cells following fluoroscopy and depicted consistent growth of tumour cells. There was also the growth of microtubules. Any dissociated organoids were then co-cultured with GBM cells again, promoting interaction between the two. Further analysis revealed the upregulation of 45 genes, including PAX6, GJA1, GPC3, and others involved in cell regulation.  

Credit to Teresa G Krieger, Stephan M Tirier, Jeongbin Park, Katharina Jechow, Tanja Eisemann, Heike Peterziel, Peter Angel, Roland Eils, Christian Conrad, Modeling glioblastoma invasion using human brain organoids and single-cell transcriptomics, Neuro-Oncology, Volume 22, Issue 8, August 2020, Pages 1138–1149

In conclusion, this novel mechanism of analysis of GBM cells using Aggrewell plates provided fruitful results, indicating intricate relationships between GBM cells and organoids, providing crucial insight for treatments by elucidating specific gene expression, heterogeneity of cells, and offering new targets based on ligand-receptor interactions. The particular relevance of this study to my work is regarding the usage of Aggrewell plates, which I am currently studying to determine how best to keep cells growing successfully within the wells. This article proves the usability and efficiency of Aggrewell and establishes its crucial role in the realm of brain cancer treatment research.  

Written by Shreya Sankar

#JournalClub with Alysia: How exosomes can promote cancer spread?

Hi, it’s Alysia, here to give you some insight on exosomes’ impact on tumor metastatic niche formation! I found an interesting paper related to my work that I want to share with you: Tumour-derived exosomes drive immunosuppressive macrophages in a pre-metastatic niche through glycolytic dominant metabolic reprogramming.

Exosomes have been a groundbreaking field of research due to their hypothesized ability to create a pre-metastatic niche through non-cancerous cell manipulation. They achieve this by relaying oncogenes and proteins from cancer cells in their molecular “cargo”. In this study, Morrissey et al. examined the role of tumor-derived exosomes (TDEs) in increasing programmed death ligand-1 (PDL-1) expression in macrophages. In pre-metastatic tumour microenvironments, there is an increase in inflammation and an immunosuppressive response, thus promoting tumorigenesis. PDL-1 is increased by TDEs manipulating the signalling of toll-like receptor 2 (TLR2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), which increases lactate production and glucose uptake in an event called the “Warburg Effect”, which is common in tumour microenvironments. TDEs taken from lung cancer samples were injected into mice, and PDL-1 expression levels of macrophages were higher than in healthy lung samples.

To accomplish this, Lewis lung carcinoma tumour cells (derived from mice) labelled with a green fluorescent protein (LLC-GFP+) were injected into mice with tumours; seven days later, they were injected with either non-GFP LLC exosomes or control mouse lung epithelial cell exosomes (MLE-12). The mice injected with non-GFP LLC exosomes had no metastatic difference compared to the control mice. However, the mice injected with LLC-GFP+ exosomes had an increase in micro-metastases, which was confirmed using fluorescent microscopy to observe LLC-GFP+ occurrence. With confocal microscopy, they observed an increase in PDL-1 expression in lung tissue compared to the control mice. These findings suggest that PDL-1 expression is preferentially increased in lung tumour tissue by injecting LLC-GFP+ exosomes.

Figure A. Schematic of experimental design. Figure B. Micro-metastatic burden quantified by LLC-GFP% in the lungs of s.c. GFP-LLC tumour-bearing mice treated intravenously (i.v.) with MLE-12 or LLC exosomes. Representative dot plots of GFP expression in the lungs and summarized data of LLC-GFP% are shown. Each dot represents data from one mouse. *p < 0.05, one-way ANOVA with multiple comparisons. Figure C. Confocal microscopic analysis of lung GFP+ micro-metastases from primary s.c. LLC tumor-bearing mice. Figure D. Confocal microscopic analysis of PD-L1 expression in LLC Exo- or LLC Exo+ -treated lungs. Adapted from Morrissey et al.

Researchers also examined the clinical significance of human TDEs and their manipulation of macrophages in the lymph nodes of non-small-cell lung cancer (NSCLC) patients. They found that there was increased expression of PDL-1 in the lymph nodes of these patients. To further study this, the researchers treated macrophages with either MLE-12 or LLC exosomes and then put them in a co-culture with OVA transgenic T-cells (a type of immune cell). The T-cells had a decrease in cell proliferation, which was later reversed by adding neutralizing α-PD-1 to the co-culture. This led them to think that PDL-1 had an inhibitory effect on T-cell function through macrophage stimulation. In summary, this study found that TDEs have an impact on PDL-1 expression found in tumour tissue and pre-metastatic tissue, resulting in creating an immunosuppressed environment for cancer cell growth. In my project, I’m interested in what cargo exosomes can carry from parental tumour cells to non-cancerous cells when creating a pre-metastatic niche. Knowing that there has been documented manipulation of the cellular makeup by exosomes encourages me to continue my research using neuroblastoma cells to elucidate the oncogenic markers relayed by exosomes. This research is very exciting, and I hope to shed some light on exosome impact in neuroblastoma tumour microenvironments with my own work!

Written by Alysia Scott

#JournalClub with Ronja: What can we learn from other cancers?

In this row of journal club blog posts, I’ve decided to look at this study: A Tumor Microenvironment Model of Pancreatic Cancer to Elucidate Responses toward Immunotherapy.

In this study, researchers developed an advanced model to simulate the environment surrounding pancreatic cancer cells. Using a specialized hydrogel matrix, they encapsulated pancreatic cancer cells, patient-derived stromal cells (non-cancerous cells that influence tumour behaviour), and immune cells. Within this matrix, the cells grew and formed spheroids, closely resembling the structure of tumours in the body. By fine-tuning the hydrogel’s properties, they controlled the stiffness and adhesion, optimizing conditions for cell growth and interaction, thereby enhancing the model’s resemblance to real-life pancreatic cancer. The researchers tested this model to evaluate its effectiveness in assessing new treatments, particularly immunotherapies. They treated the 3D cultures with a combination of immune and chemotherapy drugs and monitored the cells’ responses (See Figure). Notably, they focused on the novel drug ADH-503. Their findings revealed that the model accurately mirrored the responses observed in actual pancreatic cancer patients, confirming its validity for preclinical drug testing.

Furthermore, they explored the impact of these treatments on the secretion of cytokines—proteins crucial for immune regulation and tumour progression. They observed changes in the levels of specific cytokines (IL6 and IL8), indicating that the treatments could alter the tumour microenvironment and potentially improve therapeutic outcomes.

Figure 1 Multicellular spheroids of pancreatic cancer, patient-derived fibroblasts and immune cells stained for cell nuclei(blue), cytoskeleton and proliferating cells. From left to right, (i) untreated control, (ii) ADH-503 and immunotherapeutic, (iii) ADH-503 and chemotherapeutics and (iv) ADH-503 and both immuno- and chemotherapeutics. Modified from Adv Healthcare Materials, Volume: 12, Issue: 14, First published: 23 November 2022, DOI: (10.1002/adhm.202201907)

Overall, this study highlights the utility of their model for testing new therapies and gaining insights into the complex interactions within pancreatic tumours. It provides a robust platform for further research to develop more effective treatments for pancreatic cancer. While the study primarily focuses on pancreatic cancer, its findings and methodology have significant relevance to neuroblastoma research. Like pancreatic cancer, neuroblastoma is a solid tumour with a complex microenvironment that influences its growth and response to therapy. Thus, the model developed in this study, which accurately mimics the tumour microenvironment and allows for the testing of immunotherapies and combination treatments, could be adapted for neuroblastoma research. More directly relevant is the combination therapy of ADH-503 with immunotherapy and chemotherapy, underscoring the potential for this approach in treating other types of solid tumours like neuroblastoma. For my project, specifically, this study is helpful because it shows the relevance of immunotherapeutics on the immune cells present and their behaviour, which I plan to investigate for neuroblastoma in the future.

Written by Ronja Struck

#JournalClub: Anti-Cancer Immunotherapy

Hi there, Federica here! In the fast-paced world of scientific research, staying informed about the latest studies and breakthroughs is crucial. It enables researchers to build upon existing knowledge, avoid redundant efforts, and discover new directions for their work. That’s why we’ve started a new series of blog posts highlighting recent papers and explaining their significance for our research.

Recently, a fascinating study explored an innovative method to boost the effectiveness of cancer immunotherapy: “A combination of a TLR7/8 agonist and an epigenetic inhibitor suppresses triple-negative breast cancer through triggering anti-tumour immune“.

The researchers investigated a combination of immune checkpoint blockade (ICB) and other drugs to turn “immune-cold” tumours (which evade the immune system) into “immune-hot” tumours (which the immune system can attack). They developed a special delivery system using nanoparticles called metal-organic frameworks (MOFs). These nanoparticles were loaded with two types of drugs—a TLR7/8 agonist and an epigenetic inhibitor (BRD4 inhibitor). To make the nanoparticles even more effective, they were coated with vesicles from the cancer cells themselves. This coating helps the nanoparticles specifically target cancer cells.

But how does it work?

The nanoparticles are designed to find and enter triple-negative breast cancer (TNBC) cells. Once inside, the drugs prompt the cancer cells to break apart and release signals that alert the immune system. These signals attract dendritic cells, which then activate CD8+ T cells—the body’s natural cancer fighters. The TLR7/8 agonist further enhances this immune response, making the treatment more powerful.

In both laboratory tests and animal models, this method showed significant promise. It not only slowed down tumour growth but also improved the body’s immune response to cancer. Importantly, the study found that this approach could remodel the tumour environment, making it more hostile to cancer cells. For example, they wanted to verify that their combined delivery system could really boost the body’s ability to fight tumours. They focused on a protein called calreticulin (CRT) that, when it shows up on the surface of tumour cells, helps the immune system spot and remove them. They found that when they used their special delivery system (CM@UN and MCM@UN), the levels of CRT on the surface of tumour cells went way up. This was especially true for the MCM@UN group, showing just how powerful their method was in getting the immune system to attack the tumours.

The original image was published in J Nanobiotechnology. 2024; 22: 296.

So, why is this study important for my work?

The principles of enhancing the immune system’s ability to fight cancer are central to both the research in the study and in my project. Like the nanoparticles in the study, mRNA vaccines can be designed to specifically target cancer cells, ensuring that the treatment reaches its intended destination. Another similarity is how the drugs activate the immune system, which parallels how mRNA vaccines work—by training the immune system to recognise and attack cancer cells.

I find this study really interesting as it sheds light on innovative strategies for cancer treatment and provides valuable insights that can inform and inspire our research on developing mRNA vaccines for childhood neuroblastoma!

Written by Federica Cottone

Class 2024: Congratulations to Ciara, Ellen and Rabia!

Massive congratulations on the official moulding of PhD and MSc by Research to our promising young scientists: Rabia Saleem, Dr Ciara Gallagher and Dr Ellen King! Great accomplishments!

Three different journeys, with two through the COVID-19 pandemic. The full range of ups and downs. Who said that the PhD is a straight line? It has never been. It is more like the Irish weather: some days are sunny and bright, and some have scattered showers, gale winds and stormy snow, with sunshine developing elsewhere. The journey was spiced up with publications, conferences, travels, days out and fundraising events with the team.

It is a proud moment for me as well. 🙂 Three PhD and one MSc by Research students graduated within the last 12 months.

Of note, Ellen was behind our Twitter activities in the past, making our team visible!

Wish you all the best of luck on your new adventure!

Olga Piskareva

How things work in science: Gene editing technology

Few advancements in biomedical sciences hold as much promise for revolutionising cancer research as CRISPR-Cas9. This ground-breaking gene-editing tool has sparked a wave of innovation, offering precision and efficiency in manipulating the human genome in the fight against cancer.

Now, what is it? CRISPR is basically an acronym for a very long name Clustered Regularly Interspaced Short Palindromic Repeats Associated Protein 9 or CRISPR-Cas9 for short. It was found in simple organisms such as archaea and bacteria. Interestingly, this is a component of bacterial immune systems that can cut DNA. So, this feature was proposed for use as a gene editing tool, a kind of precise pair of molecular scissors that can cut a target DNA sequence. So, the CRISPR-Cas9 scissors allow us to precisely edit the DNA sequence of living organisms by adding in (knock-in) or removing (knockout) a gene of interest.

For cancer research, for example, the CRISPR-Cas9 scissors can be used to introduce therapeutic genes or correct mutations associated with cancer predisposition syndromes. Meanwhile, those scissors can also disrupt genes involved in treatment resistance, sensitising cancer cells to existing therapies.

Jennifer Doudna and Emmanuelle Charpentier have won the 2020 Nobel Prize in Chemistry “for the development of a method for genome editing.”. A nice accompanying piece was published in The Conversation, highlighting the history of these scissors and the politics behind it.

Jennifer Doudna explains this revolutionary genetic engineering tool in a TED lecture. However, she warns:

“All of us have a huge responsibility to consider carefully both the unintended consequences as well as the intended impacts of a scientific breakthrough.”

I hope you enjoyed it!

Witten by Rabia Saleem

How things work in science: targeting cell components.

How do researchers study cells? How do we get the nitty gritty?

We use many methods to tag and chase various cell components. One of my favourites is fluorescent microscopy. It allows the use of nearly all spectrum of colours from blue to purple in one go. However, we prefer to narrow it down to 2-3 colours and avoid their overlap.

How does it work? First, we use DAPI or Hoescht, which are blue fluorescent dyes used to stain DNA. This way, we tag the nucleus of the cell. Then, we tag a protein of interest. In our case, it was MYCN, a protein that acts as a transcription factor. MYCN amplification is associated with poor prognosis in neuroblastoma. As a transcription factor, it binds to genomic DNA and is located in the nucleus. We used a specific antibody that was labelled with a green fluorescent dye. Look at the image below. The green colour pattern overlaps with the blue colour. Then, we tagged the cytoskeleton, a complex of various proteins that hold the cell architecture and dynamics. We used phalloidin with red fluorescence. It is a highly selective bicyclic peptide and a popular choice for staining actin filaments.

Neuroblastoma organoids stained with DAPI, Phalloidin and anti-MYCN antibody. This work was done during the Fulbright journey to Ewald’s Lab at Johns Hopkins

Now, we can enjoy visualising cells and test different research questions. For example, how do cells respond to a drug? Or how do neuroblastoma cells spread?

Written by Olga Piskareva

How things work in Science: Tìr na nÒg

In humans, NANOG, SOX2, and OCT4 are transcription factors that maintain the undifferentiated state of embryonic stem cells (ESCs). NANOG was first discovered in 2003 by Chambers et al. and Mitsui et al. as a transcription factor in ESCs responsible for cellular self-renewal. More importantly, it enables continuous self-renewal of cancer stem cells, leading to metastasis when the regulatory genes involved do not function normally. These have been identified as cancer stem cells, with NANOG being a marker of “stemness”. In multiple cancer types, NANOG has various effects, including cellular expression of mesenchymal phenotype, cellular invasion/migration, repressed apoptosis, drug resistance, and increased angiogenesis. In pathways, NANOG either promotes or represses the expression of other genes that lead to cancer-favoured cellular behaviour. Overall, a higher expression level of NANOG is usually indicated in cases of poor prognosis.

NANOG is even more interesting due to its eponym, which comes from Tìr na nÒg. A Celtic myth of the Land of Youth, where the Tuath Dé resided in a supernatural land of paradise. This land offered beauty, health, joy, and everlasting youth to the inhabitants. As the myth goes, the Tuath Dé were gods of the land, and the god that ruled, Manannán mac Lir, was the first ancestor of humans. In various Celtic legends, humans are invited by the gods to visit Tìr na nÒg on great adventures.

However, time passes much slower in Tìr na nÒg, making it precarious for humans to return to their own world. As is the fateful tale of Oisín, who fell in love with the Tìr na nÒg goddess, Niamh. He travelled with her to Tìr na nÒg, where they lived happily in paradise. Upon a visit back to Ireland, Oisín realized that all his family had died over the years. When Oisín found a group of men who were struggling to move a giant rock, he stopped to lend them a hand while on his horse. However, the weight of the rock caused his saddle strap to snap. He fell from his horse, and when he touched the ground, he suddenly aged 300 years all at once.

Written by Alysia Scott

Sources:

Gawlik-Rzemieniewska, Natalia, and Ilona Bednarek. “The role of NANOG transcriptional factor in the development of malignant phenotype of cancer cells.” Cancer biology & therapy vol. 17,1 (2016): 1-10.

The Story of Tír Na NÓg.” Celtic Titles, 10 Feb. 2022

Congratulations to Dr Ciara Gallagher!


Huge congrats to a newly minted Dr Ciara Gallagher!  She defended her PhD on March 8 – International Women’s Day. Your enthusiasm and perseverance are truly fascinating! May this be the stepping stone towards a brighter future, Ciara!

We thank examiners Dr Marie McIlroy (RCSI) and Prof Jan Škoda (Masaryk Uni) for the time and expertise they provided.

We also thank the Irish Research Council for their generous support!

Dr Ciara Murphy (Chair), Dr Olga Piskareva (Supervisor), Dr Ciara Gallagher, Prof Jan Skoda (examiner), Dr Marie McIlroy (Examiner)

Ever wonder how scientists figure out a specific protein’s role in cancer?

Researchers use various methods, but I employ gene knockdown in my experiments. Basically, I use small RNA molecules that specifically target and degrade the mRNA of my gene of interest. This leads to a decrease in the corresponding protein levels, enabling me to observe the effects on neuroblastoma cell behaviour.

I feel a bit like Sherlock Holmes, you know? I’m selectively putting my suspect protein – the one I’m eyeing – under the spotlight to see how it’s pulling the strings on the cell’s behaviour. It’s like I’m in a cellular mystery, complete with a gene knockout magnifying glass 🔍🧬🕵

So, what I’ve been up to these past months is knocking down my protein and trying to find answers to the following questions:

Can neuroblastoma cells survive? And if not, how do they meet their demise? Do they go on a growth spree and start proliferating? Are they capable of migration? And here’s the twist – when my protein of interest takes a dip, do other proteins decide to change their expression levels?

The picture below can probably help you get an idea of what I’ve done so far. Do you see those brighter spots in Pictures A and B? Those are dead cells. Their number indicates the proportion of dead cells after a treatment. Picture A has just a few; the majority are healthy and well-spread cells. This is our negative control, a condition when we show neuroblastoma cells that have been transfected, but no gene knockdown happened. Transfection is the term for introducing small RNA molecules. Now, in Picture B, when we knocked down the protein, it caused the death of the cells, and you can clearly see that from all those many little bright spots.

We have found answers to many of the previous questions, but new questions have arisen, and we can’t wait to answer them!

Written by Federica Cottone