Resistance to caspase-8 and -9 fragments in a malignant pleural mesothelioma cell line with acquired cisplatin-resistance

Abstract

Apoptotic cysteine–aspartate proteases (caspases) are essential for the progression and execution of apoptosis, and detection of caspase fragmentation or activity is often used as markers of apoptosis. Cisplatin (cis-diamminedichloroplatinum (II)) is a chemotherapeutic drug that is clinically used for the treatment of solid tumours. We compared a cisplatin-resistant pleural malignant mesothelioma cell line (P31res1.2) with its parental cell line (P31) regarding the consequences of in vitro acquired cisplatin-resistance on basal and cisplatin-induced (equitoxic and equiapoptotic cisplatin concentrations) caspase-3, -8 and -9 fragmentation and proteolytic activity. Acquisition of cisplatin-resistance resulted in basal fragmentation of caspase-8 and -9 without a concomitant increase in proteolytic activity, and there was an increased basal caspase-3/7 activity. Similarly, cisplatin-resistant non-small-cell lung cancer cells, H1299res, had increased caspase-3 and -9 content compared with the parental H1299 cells. In P31 cells, cisplatin exposure resulted in caspase-9-mediated caspase-3/7 activation, but in P31res1.2 cells the cisplatin-induced caspase-3/7 activation occurred before caspase-8 or -9 activation. We therefore concluded that in vitro acquisition of cisplatin-resistance rendered P31res1.2 cells resistant to caspase-8 and caspase-9 fragments and that cisplatin-induced, initiator-caspase independent caspase-3/7 activation was necessary to overcome this resistance. Finally, the results demonstrated that detection of cleaved caspase fragments alone might be insufficient as a marker of caspase activity and ensuing apoptosis induction.

Chemical Composition and In Vitro Cytotoxicity of Essential Oils from Leaves and Flowers of Callistemon citrinus from Western Himalayas

“…Blotting was performed as described earlier [ 34 ]. In brief, the cells were harvested and lysed in RIPA buffer (Sigma-Aldrich).…”

Molecular mechanisms of cisplatin resistance

“…Several dozens of proteins (including death receptors, cytoplasmic adaptors, pro-and antiapoptotic members of the BCL-2 protein family, caspases, calpains, mitochondrial intermembrane proteins and many others) participate in these lethal cascades and most of them have been shown to modulate the response to cisplatin (as well as to a plethora of other chemotherapeutic agents, drugs, toxins and stressors) in vitro (de La Motte Rouge et al, 2007;Sakai et al, 2008;Tajeddine et al, 2008;Wang et al, 2010;Janson et al, 2011). However, only some of these proteins predict cisplatin responsiveness in the clinical setting.…”

Verotoxin-1 Treatment or Manipulation of its Receptor Globotriaosylceramide (Gb3) for Reversal of Multidrug Resistance to Cancer Chemotherapy

“…Shiga toxins also inhibit the expression of the anti-apoptotic Bcl-2 family member Mcl-1 [ 25 ]. Interestingly, acquisition of cisplatin resistance in MPM cells decreased cisplatin activation of the proapoptotic proteins of the Bcl-2 family of proteins [ 26 ] and increased the expression of apoptosis inhibitor proteins [ 27 ].…”