Anticancer mechanism studies of iridium(III) complexes inhibiting osteosarcoma HOS cells proliferation.

Three iridium (III) polypyridine complexes [Ir(bzq)2(maip)](PF6) (Ir1，bzq = benzo[h]quinoline, maip = 3-aminophenyl-1H-imidazo[4,5-f][1,10]phenanthroline), [Ir(bzq)2(apip)](PF6) (Ir2, apip = 2-aminophenyl-1H-imidazo[4,5-f][1,10]phenanthroline) and [Ir(bzq)2(paip)](PF6) (Ir3, paip = 4-aminophenyl-1H-imidazo[4,5-f][1,10]phenanthroline) were synthesized and characterized. The cytotoxic activities of the three complexes against human osteosarcoma HOS, U2OS, MG63 and normal LO2 cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method. The results showed that Ir1-3 exhibited moderate antitumor activity against HOS with IC50 of 21.8 ± 0. 4 µM,10.5 ± 1.8 µM and 7.4 ± 0.4 µM, respectively. We found that Ir1-3 can effectively inhibit HOS cells growth and blocked the cell cycle at the G0/G1 phase. Further studies revealed that complexes can increase intracellular reactive oxygen species (ROS) and Ca2+, which accompanied by mitochondria-mediated intrinsic apoptosis pathway. In addition, autophagy was also investigated. Taken together, the complexes induce HOS apoptosis through a ROS-mediated mitochondrial dysfunction pathway and inhibition of the PI3K (phosphatidylinositol 3-kinase)/AKT (protein kinase B)/mTOR (mammalian target of rapamycin) signaling pathway. This study provides useful help for understanding the anticancer mechanism of iridium (III) complexes toward osteosarcoma treatment.

Antitumor activity studies of iridium (III) polypyridine complexes-loaded liposomes against gastric tumor cell in vitro.

Two iridium (III) polypyridine complexes [Ir(ppy)2(BIP)]PF6 (ppy = 2-phenylpyridine, BIP = 2-biphenyl-1H-imidazo[4,5-f][1,10]phenanthroline, Ir1), [Ir(piq)2(BIP)]PF6 (piq = 1-phenylisoquinoline, Ir2) and their liposomes Ir1lipo and Ir2lipo were synthesized and characterized. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate cytotoxic activity against several cancer cells (A549, HepG2, SGC-7901, Bel-7402, HeLa) and non-cancer cell (mouse embryonic fibroblast, NIH3T3). The results showed that Ir1lipo displays the high cytotoxicity toward SGC-7901 with IC50 value of 5.8 ± 0.2 µM, while the complexes have no cytotoxicity toward A549, HepG2, Bel-7402 and HeLa cells. The cell colony demonstrated that the iridium (III) complexes-loaded liposomes can inhibit cell proliferation, induce cell cycle arrest at G0/G1 phase. Moreover, they also cause autophagy, induce a decrease of mitochondrial membrane potential and increase intracellular reactive oxygen species (ROS) content. These results suggest that the complexes encapsulated liposomes Ir1lipo and Ir2lipo inhibit the growth of SGC-7901 cells through a ROS-mediated mitochondrial dysfunction and activating the PI3K (phosphoinositide-3 kinase)/ AKT (protein kinase B) signaling pathways.

A novel antisense long non-coding RNA SATB2-AS1 overexpresses in osteosarcoma and increases cell proliferation and growth.

The knowledge regarding the importance of long non-coding RNAs (lncRNAs), a new class of genes, is very sparse in osteosarcoma. In the present study, we describe the expression profile of lncRNAs in osteosarcomas compared with paired adjacent non-cancerous tissue (n = 7) using microarray analysis. A total of 25,733 lncRNAs were identified in osteosarcoma; 1995 lncRNAs were consistently upregulated and 2226 lncRNAs were consistently under-regulated in all samples analyzed (≥2.0-fold, p < 0.05). We have validated three over-regulated and three under-regulated lncRNAs in patient samples (n = 7). The antisense transcript of SATB2 protein (SATB2-AS1) was identified as one of the upregulated lncRNAs. The SATB2-AS1 is a 3197-bp lncRNA on chromosome 2. This is the first report, where we have documented the increased expression of SATB2-AS1 in osteosarcoma patients and in human osteosarcoma cancer cell lines (U2OS, HOS, MG63). SATB2-AS1 expression was significantly higher in the metastatic tumors compared to non-metastatic tumors. In vitro gain and loss of function approaches demonstrated that SATB2-AS1 regulates cell cycle, cell proliferation, and cell growth. In addition, SATB2-AS1 affects the translational expression of SATB2 gene. Our data demonstrate that an antisense non-coding RNA regulates the expression of its sense gene, and increases the cell growth, therefore pointing the pivotal functions of SATB2-AS1 in osteosarcoma.

Anticancer Activity Studies of Ruthenium(II) Complex Toward Human Osteosarcoma HOS Cells.

A new Ru(II) complex [Ru(dmp)2(NMIP)](ClO4)2 (dmp = 2,9-dimethyl-1,10-phenanthroline, NMIP = 2'-(2″-nitro-3″,4″-methylenedioxyphenyl)imidazo[4',5'-f][1,10]-phenanthroline) was synthesized and characterized by elemental analysis, ESI-MS and (1)H NMR. The cytotoxic activity of the complex against MG-63, U2OS, HOS, and MC3T3-e1 cell lines was investigated by MTT method. The complex shows moderate cytotoxicity toward HOS (IC50 = 35.6 ± 2.6 µM) and MC3T3-e1 (IC50 = 41.6 ± 2.8 µM) cell lines. The morphological studies show that the complex can induce apoptosis in HOS cells and cause an increase of reactive oxygen species levels and a decrease in the mitochondrial membrane potential. The cell cycle distribution demonstrates that the complex inhibits the cell growth at S phase. Additionally, the antitumor activity in vivo reveals that the complex can induce a decrease in tumor weight.

Protein-binding, cytotoxicity in vitro and cell cycle arrest of ruthenium(II) polypyridyl complexes.

The cytotoxic activity of two Ru(II) complexes against A549, BEL-7402, HeLa, PC-12, SGC-7901 and SiHa cell lines was investigated by MTT method. Complexes 1 and 2 show moderate cytotoxicity toward BEL-7402 cells with an IC50 value of 53.9 ± 3.4 and 39.3 ± 2.1 µM. The effects of the complexes inducing apoptosis, cellular uptake, reactive oxygen species and mitochondrial membrane potential in BEL-7402 cells have been studied by fluorescence microscopy. The percentages of apoptotic and necrotic cells and cell cycle arrest were studied by flow cytometry. The BSA-binding behaviors were investigated by UV/visible and fluorescent spectra.

Effect of radiation on cytotoxicity, apoptosis and cell cycle arrest of human osteosarcoma MG-63 induced by a ruthenium(II) complex.

Radiation has large influence on the cytotoxicity, apoptosis and cell cycle arrest. The bioactivity of ruthenium(II) complex [Ru(dmb)2(DBHIP)](ClO4)2 (Ru1) (DBHIP=2-(3,5-dibromo-4-hydroxylphenyl)imidazo[4,5-f][1,10]phenanthroline) was investigated in the absence and presence of radiation. The cytotoxicity of Ru1 against MG-63 cells was evaluated by CCK-8 method. Ru1 shows high cytotoxicity upon radiation. Radiation can enhance the cytotoxicity of Ru1 on MG-63 cells. The apoptosis was studied by Hoechst 33258 staining method and flow cytometry. The reactive oxygen species, mitochondrial membrane potential, cell cycle arrest and western blot analysis were investigated in detail. The complex induces the apoptosis in MG-63 cells through ROS-mediated mitochondrial dysfunction pathway.

Cytotoxicity, apoptosis, cellular uptake, cell cycle distribution, and DNA-binding investigation of ruthenium complexes.

Three new ruthenium(II) polypyridyl complexes [Ru(bpy)(2)(BHIP)](2+) 1, [Ru(phen)(2)(BHIP)](2+) 2, and [Ru(dip)(2)(BHIP)](2+) 3 were synthesized and characterized. The cytotoxicity of the three complexes was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The apoptosis induced by the complexes was studied by cell morphology and flow cytometry. The results showed that the percentage of apoptotic cells is 7.19%, 75.58%, and 3.51% in the presence of complexes 1, 2, and 3, respectively. The cellular uptakes were also performed and the results indicated that complexes 1, 2, and 3 can enter into the cytoplasm and also into the nucleus. The studies on antiproliferative mechanism showed the induction of S-phase arrest by complexes 1, 2, and 3. DNA-binding constants of these complexes with calf thymus DNA (CT-DNA) were determined to be 1.07 (± 0.47) × 10(5) M(-1) (s = 2.04), 1.21 (± 0.32) × 10(5) M(-1) (s = 1.88), and 2.75 (± 0.27) × 10(5) M(-1) (s = 2.17), respectively. Upon irradiation at 365 nm, complexes 1, 2, and 3 can induce cleavage of pBR322 DNA.

Rescue and treatment of severely injured lower extremities.

OBJECTIVE: To explore a treatment approach for severely injured lower extremities. METHODS: The data of 42 patients with severely traumatic lower extremities from 1989 to 1999 were retrospectively reviewed. According to MESS (mangled extremity severity score) the mean score of all the limbs was 6.24+/-1.45, 34 cases had MESS score < 7 and 8 cases had MESS score > or = 7. Treatment approaches included microvascular anastomosis technique, compound tissue flap transplantation technique and compound bone tissue flap transplantation. RESULTS: Two patients died after operation and one patient had delayed amputation of a lower limb. The rest 39 patients were followed up for 4-13 years. All the lower extremities of the 39 patients survived and had equal length. The 39 cases were evaluated by Chen's criterion, showing that 37 had good result (29, Chen I and 8, Chen II), 1 sufficient (Chen III) and 1 poor (Chen IV). CONCLUSIONS: Successful emergency treatment of severely injured lower extremities could be achieved by using microsurgery techniques and strict controlling of lower extremity salvagel indications.

Monitoring island flap for fibular graft in 30 patients with long bone defects.

OBJECTIVE: To study the effect of vascularized fibular graft on large defects of long bones and the monitoring method for the vascular status of the grafted fibula. METHODS: From March 1988 to February 1998, 30 patients with long bone defects over 6 cm in length received vascularized fibular graft including a monitoring island flap in our department to monitor the blood circulation of the fibulae. RESULTS: Monitoring island abnormalities were indicated in 6 flaps, which accurately gave the alarm of the circulation crisis of the fibular graft. Surgical exploration was performed timely and the blood supply was recovered instantaneously. All the bone defects were healed at 6 months postoperatively. After 4 years of follow-up, all the grafted fibulae were thickened and were just like tibiae. CONCLUSIONS: A monitoring island flap is a satisfactory method for repairing large defects of the long bones and a reliable method for assessing the vascular status of the grafted fibulae.