RNA disruption is associated with response to multiple classes of chemotherapy drugs in tumor cell lines

Narendrula, Rashmi; Mispel-Beyer, Kyle; Guo, Baoqing; Parissenti, Amadeo M.; Pritzker, Laura B.; Pritzker, Ken; Masilamani, Twinkle; Wang, Xiaohui; Lannér, Carita

The degradation of DNA into internucleosomal fragments is a well-known hallmark of apoptosis [10] . Although not as well-characterized, numerous studies have shown that rRNA may also be degraded, in conjunction with apoptosis, into specific-sized fragments derived from the 28S and/or 18S rRNAs. Early studies demonstrated that both cytotoxic and apoptosis-inducing agents can induce rRNA fragmentation and apoptosis, in a variety of cell lines and types [11] [12] [13] [14] . The phenomenon is widespread, also occurring in plants, like oats [15] . Mroczek and Kufel [16] have used the term "stress-induced rRNA fragmentation" to describe the phenomenon by which various cellular stressors activate programmed cell death pathways in yeast, some of which are associated with rRNA degradation. However, the apparent connection between apoptosis and rRNA degradation is not compulsory, as it was shown that rRNA cleavage could occur in the absence of caspase-and BCL-2 dependent apoptosis [17] .