title: Differential effects of rapalogues, dual kinase inhibitors on human ovarian carcinoma cells in vitro.
abstract: Ovarian cancer is the second most common gynaecological malignancy and was diagnosed in over 7,000 women in 2011 in the UK. There are currently no reliable biomarkers available for use in a regular screening assay for ovarian cancer and due to characteristic late presentation (78% in stages III and IV) ovarian cancer has a low survival rate (35% after 10 years). The mTOR pathway is a central regulator of growth, proliferation, apoptosis and angiogenesis; providing balance between available resources such as amino acids and growth factors, and stresses such as hypoxia, to control cellular behaviour accordingly. Emerging data links mTOR with the aetiopathogenesis of ovarian cancer. We hypothesised that mTOR inhibitors could play a therapeutic role in ovarian cancer treatment. In this study we began by validating the expression of four main mTOR pathway components, mTOR, DEPTOR, rictor and raptor, at gene and protein level in in vitro models of endometrioid (MDAH‑2774) and clear cell (SKOV3) ovarian cancer using qPCR and ImageStream technology. Using a wound healing assay we show that inhibition of the mTOR pathway using rapamycin, rapalogues, resveratrol and NVP BEZ-235 induces a cytostatic and not cytotoxic response up to 18 h in these cell lines. We extended these findings up to 72 h with a proliferation assay and show that the effects of inhibition of the mTOR pathway are primarily mediated by the dephosphorylation of p70S6 kinase. We show that mTOR inhibition does not involve alteration of mTOR pathway components or induce caspase 9 cleavage. Preclinical studies including ovarian tissue of ovarian cancer patients, unaffected controls and patients with unrelated gynaecological conditions show that DEPTOR is reliably upregulated in ovarian cancer.
authors.affiliation: Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
authors.forename: Karly-Rai
authors.initials: KR
authors.lastname: Rogers-Broadway
authors.affiliation: Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
authors.forename: Dimple
authors.initials: D
authors.lastname: Chudasama
authors.affiliation: Medical School, Aristotle University, Thessaloniki, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Pados
authors.affiliation: Medical School, Aristotle University, Thessaloniki, Greece.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Tsolakidis
authors.affiliation: Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Goumenou
authors.affiliation: Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
authors.forename: Marcia
authors.initials: M
authors.lastname: Hall
authors.affiliation: Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK.
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Karteris
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000037:antagonists & inhibitors / Q000235:genetics*; D017209:Apoptosis / Q000187:drug effects; D002277:Carcinoma / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000235:genetics*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors / Q000235:genetics*; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage; D011804:Quinolines / Q000008:administration & dosage; D000076226:Rapamycin-Insensitive Companion of mTOR Protein; D000076223:Regulatory-Associated Protein of mTOR; D015398:Signal Transduction / Q000187:drug effects; D020123:Sirolimus / Q000008:administration & dosage; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D007093:Imidazoles; D047908:Intracellular Signaling Peptides and Proteins; D047428:Protein Kinase Inhibitors; D011804:Quinolines; C492571:RICTOR protein, human; C463659:RPTOR protein, human; D000076226:Rapamycin-Insensitive Companion of mTOR Protein; D000076223:Regulatory-Associated Protein of mTOR; C556139:DEPTOR protein, human; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases; C531198:dactolisib; D020123:Sirolimus