Cancer cell necrosis by autoschizis: Synergism of antitumor activity of vitamin C: Vitamin K₃ on human bladder carcinoma T24 cells

Abstract

Summary: Scanning and transmission electron microscopy and fluorescence light microscopy were employed to characterize the cytotoxic effects of vitamin C (VitC), vitamin K, (VitK,) or a VitC:VK, combination on a human bladder carcinoma cell line (T24) following 1 -h and 2-h vitamin treatment. T24 cells exposed to VitC alone exhibited membranous damage (blebs and endoplasmic extrusions, elongated microvilli). VitK,-treated cells displayed greater membrane damage and enucleation than those treated with VitC as well as cytoplasmic defects characteristic of cytoskeletal damage. VitC:VitK,-treated cells showed exaggerated membrane damage and an enucleation process in which the perikarya separate from the main cytoplasmic cell body by self-excision. Self-excisions continued for perikarya which contained an intact nucleus surrounded by damaged organelles. After further excisions of cytoplasm, the nuclei exhibited nucleolar segregation and chromatin decondensation followed by nuclear karryorhexis and karyolysis. This process of cell death induced by oxidative stress was named autoschizis because it showed both apoptotic and necrotic morphologic characteristics.

Morphology and DNA degeneration during autoschizic cell death in bladder carcinoma T24 cells induced by ascorbate and menadione treatment

“…Specifically, the cells exhibit the pleiomorphism characteristic of tumor cells as described previously by Bubeník et al (1973) and by Gilloteaux et al (1998aGilloteaux et al ( , 1998bGilloteaux et al ( , 2001aGilloteaux et al ( , 2001b. Even though the cells are subconfluent, they show overlap that is indicative of the absence of cell contact inhibition.…”

“…cells showed ultrastructural aspects consistent with autoschizic cell death (Gilloteaux et al, 1998a(Gilloteaux et al, , 1998b(Gilloteaux et al, , 2001a(Gilloteaux et al, , 2001b(Gilloteaux et al, , 2001cJamison et al, 2002Jamison et al, , 2004. The most common motif of autoschizis entails the formation of "doublets" (Ervin et al, 1998).…”

“…These studies have led to the detailed description and characterization of two types of cell death: necrosis/oncosis (Majno and Joris, 1995), and apoptosis (Kerr, 1971;Kerr et al, 1972;Wyllie, 1981;Wyllie et al, 1984). However, during the course of studies designed to evaluate the antitumor activity of sodium ascorbate (VC) and menadione bisulfite (VK 3 ) combinations against the DU145 human prostate carcinoma cell line, it was observed that cancer cells underwent cell death by using a mechanism different than necrosis or apoptosis (Gilloteaux et al, 1995(Gilloteaux et al, , 1998aJamison et al, 1996;Venugopal et al, 1996b). VC:VK 3 treatment of a second cell line (T24 bladder carcinoma) produced identical cytoplasmic and nuclear changes with specific DNA degradation (Ervin et al, 1998;Gilloteaux et al, 1998aGilloteaux et al, , 1998bGilloteaux et al, , 1999aGilloteaux et al, , 2001aGilloteaux et al, , 2001bGilloteaux et al, , 2001cJamison et al, 2004).…”

“…However, during the course of studies designed to evaluate the antitumor activity of sodium ascorbate (VC) and menadione bisulfite (VK 3 ) combinations against the DU145 human prostate carcinoma cell line, it was observed that cancer cells underwent cell death by using a mechanism different than necrosis or apoptosis (Gilloteaux et al, 1995(Gilloteaux et al, , 1998aJamison et al, 1996;Venugopal et al, 1996b). VC:VK 3 treatment of a second cell line (T24 bladder carcinoma) produced identical cytoplasmic and nuclear changes with specific DNA degradation (Ervin et al, 1998;Gilloteaux et al, 1998aGilloteaux et al, , 1998bGilloteaux et al, , 1999aGilloteaux et al, , 2001aGilloteaux et al, , 2001bGilloteaux et al, , 2001cJamison et al, 2004). After these changes were observed in other bladder cancer cell lines (J82, SCaBER, TCCSUP, RT4) (Jamison et al, 1996;Venugopal et al, 1996b), we believed that we had discovered a new form of cell death.…”

“…After these changes were observed in other bladder cancer cell lines (J82, SCaBER, TCCSUP, RT4) (Jamison et al, 1996;Venugopal et al, 1996b), we believed that we had discovered a new form of cell death. This new form of cell death was named autoschizis (from the Greek autos, self, and skhizein, to split) by Gilloteaux et al (1998aGilloteaux et al ( , 1998bGilloteaux et al ( , 1999aGilloteaux et al ( , 1999bGilloteaux et al ( , 2001aGilloteaux et al ( , 2001bGilloteaux et al ( , 2001c because this cell death is initiated by membrane defects that triggered self-excisions of the cytoplasm characterized by self-morsellations (from Latin morsus, bite). Subsequently, autoschizis has been observed in a variety of cell lines, including renal carcinoma (Caki-1) (Arnold et al, 1999), ovarian carcinoma (MDAH 2774) (Gilloteaux et al, 1999b(Gilloteaux et al, , 2003a(Gilloteaux et al, , 2003b, and murine prostatic carcinoma (TRAMP) , as well as in vivo .…”