Decoding neuroblastoma microenvironment

MCT Research Talks – 24th April 2017

The main challenge in treating high-risk neuroblastoma is to combat tumour metastasis and development of resistance to multiple chemotherapeutic drugs. In the native tissue, cancer cells are surrounded by a three-dimensional (3D) microenvironment which provides biological and physical support and determines disease initiation, progression, patient prognosis and response to treatment. The conventional two-dimensional (2D) cell culture lacks this feature resulting in discrepancies between in vitro and in vivo results. Current neuroblastoma studies employ either 2D cell culture systems or murine models or alternatively a mix of both.

In collaboration with Dr Caroline Curtin and Prof Fergal O’Biren (TERG), we decided to bridge the gap between 2D culture and in vivo tumours in neuroblastoma research by developing a tissue-engineered cell culture model of neuroblastoma. This project is supported by a pilot grant from Neuroblastoma UK.

To understand what signalling pathways are activated in 2D, 3D and in vivo neuroblastoma models, we decided to look closer at the differences between conventional 2D neuroblastoma cells and their xenografts. This way we hope to find those targets that are activated in both tumour microenvironment and the 3D tissue engineered models. Ciara and Larissa have begun this search by profiling xenograft samples with a panel of antibodies. Ciara became particularly fascinated by the elevated levels of c-jun, TCF1 and LEF1 in cisplatin-resistant neuroblastoma xenografts suggesting that the development of cisplatin resistance in neuroblastoma may be accompanied by activation of the wnt/b-catenin pathway in vivo. Larissa identified that cisplatin-resistant neuroblastoma cells secrete chromogranin A (CgA) at levels higher that cisplatin-sensitive cells. CgA levels also correlated with increased vascularisation and volume of murine orthotopic neuroblastoma xenografts. Altogether it suggests that CgA can be used as a marker of neuroblastoma cell growth both in vitro and in vivo.

Olga Piskareva

Irish Association For Cancer Research Meeting 2017

Irish Association for Cancer Research – Annual Meeting takes place at Newpark Hotel, Kilkenny on Thursday 23 and Friday 24 February 2017.

MCT cancer researchers secured oral presentations at different sessions. Prof Ray Stallings is a guest speaker at the Plenary Session focused on challenges in childhood cancers. He will be discussing ‘Modulation of neuroblastoma phenotype with epigenetically regulated miRNAs’.

Stephanie Annett will be giving a talk ‘FKBPL as a novel prognostic biomarker and therapeutic agent in high-grade serous ovarian cancer’ at Proffered Paper Session on Thursday morning. Two Irish Cancer Society funded PhD students will be discussing their findings at the Irish Cancer Society Scholar and Fellow Presentation session. Louise Walsh – ‘RNA sequencing identifies bromodomain proteins as a therapeutic strategy for invasive lobular carcinoma’ and Brian Mooney – ‘Expression of the cocaine- and amphetamine-regulated transcript recruits BAF chromatin remodelling complexes to the estrogen receptor’.

Good luck to our presenters!

Olga Piskareva

 

 

Targeting drug resistance in neuroblastoma

MCT Research Talks 5th December 2016  rcsi-logo

Cancer Genetics Group

Neuroblastoma is a childhood cancer caused by the abnormal growth and development of neural crest cells (1). The disease commonly affects children age 5 years or younger. Approximately 50% of children have cancer cells that have migrated to distant sites in the body and formed tumour masses at the time of diagnosis. The main challenge in treating neuroblastoma is to combat tumour metastasis and development of resistance to multiple chemotherapeutic drugs. Despite major advances in available therapies, children with drug resistant and/or recurrent neuroblastoma have a dismal outlook with 5 year survival rates of less than 20%.

Research of Prof. Stallings lab is focused on elucidating the molecular events that contribute to the development and progression of neuroblastoma (2).  A major area of research involves the identification and functional analysis of microRNAs that contribute to chemotherapy resistance in neuroblastoma, along with the development of microRNA-mediated therapeutics.

The main research projects were presented at the Departmental meeting on December, 5th.

Microscopic examination of drug resistant neuroblastoma cells KellyCis83. Cells look healthy and can be kept for another 2-3 days to form a more dense population.
Microscopic examination of drug resistant neuroblastoma cells KellyCis83. Cells look healthy and can be kept for another 2-3 days to form a more dense population.

The first talk by Olga Piskareva has explored how current concepts of development of drug resistant, tumour microenvironment and cell-to-cell communication can be applied to reconstruct relapsed or drug resistant neuroblastoma microenvironment using 3D tumour models.

TEM analysis of exosome fractions. Vesicle sizes range from 30 to 200nm in Kellycis83 (A) and Kelly (B) neuroblastoma cells. (C) EVs which appear larger than the 100 nm upper limit for exosomes (D) Close up of the dried exosome preps identify the typical bowl shaped morphology associated with TEM images of exosomes. (3)
TEM analysis of exosome (EV) fractions. Vesicle sizes range from 30 to 200nm in Kellycis83 (A) and Kelly (B) neuroblastoma cells. (C) EVs which appear larger than the 100 nm upper limit for exosomes (D) Close up of the dried exosome preps identify the typical bowl shaped morphology associated with TEM images of exosomes (3).

The second talk was presented by Ciara Fallon. Ciara is our StAR PhD student. She has selected the project ‘Exosome mediated drug resistance in high-risk neuroblastoma’ as her first choice.  At the moment she is doing her lab placement in Cancer Genetics group as a part of the RCSI StAR PhD Programme. Built upon results of the former BioAt PhD Student Ross Conlon (3), Ciara’s project is focused on the validation of exosomal miR-548d-5p as a regulator of cell viability and proliferation in cisplatin sensitive and resistant neuroblastoma cell lines.

Finally, the last, but not least was a talk by John Nolan. His talk entitled “MiRNA-124-3p Reduces Cell Viability in Cisplatin Resistant Neuroblastoma Cell Models” was focused on the results submitted to the Royal College of Surgeons for the Degree of Doctor of Philosophy. His studies cover the development of cross resistance to other drugs, investigation of common altered proteins and signaling pathways in cisplatin resistant neuroblastoma cell lines and validation of miRNA that can target these proteins and stop cell proliferation. Part of the results was published last year in Cancer Letters (4).

The work carried out in Prof. Stallings lab is supported through the research grant to Prof. Ray Stallings and PhD fellowship to John Nolan by National Children’s Research Centre, Crumlin Hospital. ncrc

References:

  1. Davidoff, A. M. Neuroblastoma. 2012 Semin. Pediatr. Surg. 21, 2–14.
  2. Piskareva, O., Stallings, R. Neuroblastoma. In: Epigenetic Cancer Therapy edited by Grey S., Elsevier 2015.
  3. Conlon, R., Analysis of microRNA bearing exosomes in models of drug resistant neuroblastoma. PhD Thesis. Dublin: Royal College of Surgeons in Ireland; 2015.
  4. Piskareva, O., Harvey, H., Nolan, J., Conlon, R., Alcock. L., Buckley, P., Dowling, P., O’Sullivan, F., Bray, I., Stallings, T.L. The development of cisplatin resistance in neuroblastoma is accompanied by epithelial to mesenchymal transition in vitro. 2015 Cancer Letters, 364:142-55.

Reported by Olga Piskareva