Immunocytochemical and pharmacological characterisation of P2-purinoceptor-mediated cell growth and death in PC-3 hormone refractory prostate cancer cells.
BACKGROUND
Extracellular nucleotides (e.g adenosine 5'-triphosphate, ATP) influence biological processes via purinergic receptors. We characterised the P2-purinoreceptors in human hormone refractory prostate cancer (HRPC) cells (PC-3 cells).


RESULTS
1. Immunofluorescent staining demonstrated P2X3 P2X, P2X5 P2X7 and P2Y2 receptors. 2. ATP inhibited cell growth by up to 91% over 72h. Pharmacological characterisation indicated a P2X-purinoreceptor-mediated response. 3. Comparable maximum growth inhibition was seen after either a single addition of 1mM or daily addition of 100mM ATP. ATP concentrations ([ATP]) returned to baseline levels within 24h if the initial [ATP] was < or =100 HM, while [ATP] remained high for 72h if a single concentration of 1 mM was used. 4. ATP 1 mM significantly (p<0.001) increased the proportion of cells undergoing apoptosis from 0.27% (+/- 0.04%) to 5.28% (+/- 0.77%).


CONCLUSIONS
Threshold concentrations of ATP inhibited HRPC cell growth in vitro via the activation of P2X-purinoreceptors. The role of nucleotides in the treatment of HRPC requires further investigation.
Calvert
Robert C
RC
Bedford Hospital Department of Urology, Royal Free Hospital, London, UK.
Shabbir
Majid
M
Thompson
Cecil S
CS
Mikhailidis
Dimitri P
DP
Morgan
Robert J
RJ
Burnstock
Geoffrey
G
D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D008297:Male; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D012313:RNA / Q000235:genetics; D018048:Receptors, Purinergic P2 / Q000378:metabolism / Q000502:physiology*
D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2; D012313:RNA; D000255:Adenosine Triphosphate