Novel biomarkers for docetaxel resistant in prostate cancer

Overview

Topic status: In progress

An estimated 20,000 new cases of prostate cancer (PC) are diagnosed in Australia each year with 3,300 deaths due to this disease. PC is a slow growing disease. It is regulated by androgen dependent gene pathways and its progression can be influenced by the treatment to which patients are exposed. Currently, patients who fail the first line treatments of surgery or radiation usually undergo androgen deprivation therapy (ADT). Among these, 25-40% of cases develop castrate resistance prostate cancer (CRPC) with a rise in serum levels of prostate specific antigen (PSA), a marker of tumor growth, and continue to progress with metastatic disease.

Several classes of drugs have been developed to target different pathways of PC survival, the most common being the chemotherapy drug, docetaxel, which targets tubulin. However, 30% of CRPC patients who receive docetaxel therapy relapse. Docetaxel has been shown to increase the median survival of patients but it causes severe side effects, including myelosupression and/or gastrointestinal toxicity when used at high doses. Not all patients respond positively upon administration of docetaxel. A new set of biomarkers that can predict the patient’s response for docetaxel treatment are necessary. We are interested in investigating the potential of exosomes (secreted vesicles that contain protein, mRNA and miRNA that reflect the cells of origin) for their ability to provide potential biomarkers for drug resistant prostate cancer.

Our lab has generated docetaxel resistant PC3 derived cells through several passages in mice (RX2DTR, docetaxel resistant and RX2LN, resistant to docetaxel and migrates to lymph nodes when implanted in vivo). The morphology of these cell lines differs from that of the parental prostate cancer cells PC3. Mass spec and microarray analysis show some up- and down- regulation of mRNA and proteins, including proteins involved in secretory vesicle formation such as the Rab protein family and cytoskeletal proteins (laminin). We seek an enthusiastic student who is interested in learning basic skills such as cell culture (in 2D and 3D), confocal microscopy techniques to investigate the aberrant intracellular localisation of these proteins in cells grown in 2D tissue culture dishes or 3D matrices, and protein analysis techniques including western blot. Future studies will include investigating the role of confirmed proteins in secretory pathways and whether these proteins are involved in exosome biogenesis.

Research activities

The research activities for this project include:

  • in vitro cell culture (2D and 3D)
  • confocal microscopy
  • protein analysis including western blot
  • siRNA, qRT PCR
  • exosome isolation and purification.

Expected outcomes

The expected outcomes for this project are:

  • to confirm the protein levels and intracellular localisation of Rab and cytoskeletal proteins in 2D and 3D cell culture
  • to confirm the role of those candidate proteins by siRNA and qRT PCR, followed by confocal microscopy
  • isolation and analysis of exosomes secreted by PC3, RX2DTR and RX2LN (mass spec).

Duration of project

15 Nov 2011 to 10 Feb 2012

Number of hours

10 hours per week

Study level
Vacation research experience scholarship
Supervisors
QUT
Organisational unit

Science and Engineering Faculty

Research area

Cell and Molecular Biosciences

Contact
Please contact a supervisor for enquiries.