Antiproliferative and cytotoxic effect of a novel organotin compound on mammalian cells both in vitro and in vivo

Synthesis and in vitro cytotoxicity study of three di-organotin(IV) Schiff base di-acylhydrazone complexes

Three di-organotin(IV) complexes have been synthesized by the reaction of Schiff base di-acylhydrazone ligands bis(5-chlorosalicylaldehyde) adipoylhydrazone and R2SnCl2 [R = Me (1), Ph (2), n-Bu (3)]. Structures of all complexes were characterized by 1H, 13C, 119Sn NMR, elemental analysis, IR and mass spectrometry. Experimental results showed that the symmetric diacylhydrazone ligands coordinate the tin atom in a hexadentate form, where the tin atom shows a penta-coordination, in a distorted triangular bipyramid geometry. Using MTT method, in vitro cytotoxicity of three complexes was determined against three cancer cell lines (A549, HeLa, HepG-2). Studies reveal that complex 3 showed the strongest cytotoxic activity among the three complexes, which may be correlated with the generation of intracellular reactive oxygen species. Uptake of complex 3 into cells and promotion of reactive oxygen species were visualized by confocal fluorescence imaging.

Therapeutic properties of organotin complexes with reference to their structural and environmental features

Organotin complexes are being extensively studied and screened for their therapeutic potential. Although many recent advances and achievements in this field have been made, the exact mode of action of these complexes is yet to be unveiled. In the present review, an attempt has been made to correlate the therapeutic properties of organotin complexes with their structural features and the environment in which these interact with biological systems. The mechanism, various modes of interaction with biological systems, and physiological target sites of organotin complexes have been highlighted as well.

New cytotoxic butyltin complexes with 2-sulfobenzoic acid: Molecular interaction with lipid bilayers and DNA as well as in vitro anticancer activity

New butyltin complexes with 2-sulfobenzoic acid: [Sn(C4H9)2{O3SC6H4COO-2}(H2O)]·(C2H5OH) (DBTsbz), [Sn(C4H9)3{O3SC6H4COOH-2}] (TBTsbz) and [Sn2(C4H9)6{μ-O3SC6H4COO-2}] (DTBTsbz) are very effective cytotoxic agents against tumor cells. The molecular interaction of these complexes with lipid membranes and DNA has been investigated. The IR spectra and changes of (1)H, (13)C chemical shifts suggest that SO3 and COO groups of 2-sulfobenzoato ligand interact with O atom of glycerin fragment of DPPC. Moreover, the compounds form Sn-OP bonds with phosphate groups of DPPC, which was shown by the lower frequency shift of the νs(PO2(-)) and νas(PO2(-)) band, by change of (31)P NMR signals and by DFT calculation. Another possibility is the interaction of the phosphate group of DPPC owing to formation of hydrogen bond O-H…O-P between water molecule coordinated to Sn and oxygen atom from the phosphate group. Using TCSPC-FCS we characterized DNA supramolecular assemblies' formation upon increasing TBTsbz, DTBTsbz and DBTsbz concentration. Diffusion time, lifetime and particle number changes are altered systematically with increasing Ccomp/CDNAbp ratio in following effectiveness order DBTsbz > TBTsbz > DTBTsbz. From those parameters we can conclude that all these compounds lead to a change of DNA winding, strand but not to DNA compaction. Investigated compounds show very high cytotoxic activity against cancer cell lines. All compounds exhibit efficient in vitro antitumor activity toward Jurkat (T-cell leukemia), CL-1 (T-lymphoblastoid cell line), GL-1 (B cell lymphoma cell line) and D-17 (canine osteosarcoma). The DBTsbz is more effective then carboplatin against canine osteosarcoma.

Study of the effect of molecular structure and alkyl groups bound with tin(iv) on their cytotoxicity of organotin(iv) 2-phenyl-4-selenazole carboxylates

Five organotin(iv) compounds Ph₃SnL (1), (R₂Sn)₄O₂L₄ [R = n-Bu (2), n-Oct (3)], (R₂Sn)₄O₂L₂Cl₂ [R = n-Bu (4), Me (5)], HL = 2-phenyl-4-selenazole carboxylic acid, were synthesized, of which triphenyl- and di-n-butyltin(iv) compounds display higher in vitro cytotoxicities.

Modulation of cytotoxic and genotoxic effects of nanoparticles in cancer cells by external magnetic field

Magnetic nanoparticles are well known for anticancer activity by deregulating cellular functions. In the present study, cellular effects of low strength static magnetic field (SMF) were explored. How nanoparticles affect the cellular response in presence and absence of static magnetic field was also studied. Peripheral blood mononuclear cells (PBMC) and human lymphoma monocytic cell line U937 were chosen as representative normal and cancer cells models. The two effects we would like to report in this paper are, DNA damage induced by SMF of the order of 70 mT, and alteration in membrane potential. The other notable aspect was the changes were diametrically opposite in normal and cancer cell types. DNA damage was observed only in cancer cells whereas membrane depolarization was observed in normal cells. Iron oxide nanoparticles (IONP) and gold nanoparticles (AuNP) were also used for cellular response studies in presence and absence of SMF. The effects of the magnetic nanoparticle IONP and also of AuNP were sensitive to presence of SMF. Unlike cancer cells, normal cells showed a transient membrane depolarization sensitive to static magnetic field. This depolarization effect exclusive for normal cells was suggested to have correlations with their higher repair capacity and lesser propensity for DNA damage. The work shows cancer cells and normal cells respond to nanoparticle and static magnetic field in different ways. The static magnetic induced DNA damage observed exclusively in cancer cells may have therapeutic implications. From the conclusions of the present investigation we may infer that static magnetic field enhances the therapeutic potentials of nanoparticles. Such low strength magnetic field seems to be a promising external manoeuvring agent in designing theranostics.

Cytotoxicity of triphenyltin(IV) methyl- and ethylisopropyldithiocarbamate compounds in chronic myelogenus leukemia cell line (K-562)

Studies on the discovery of new cancer treatment by using metal-based compounds such as tin (Sn) has now greatly being synthesized and evaluated to identify their effectiveness and suitability to be developed as a new anticancer drug.

APPROACH

This study was carried out to evaluate the cytotoxicity of triphenyltin(lV) methylisopropyldithiocarbamate (compound 1) and triphenyltin(IV) ethylisopropyldithiocarbamate (compound (2) on chronic myelogenus leukemia cells. The determination of their cytotoxicity (IC50) at different time of exposure and concentration was carried out through the employment of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay.

RESULTS

The IC50 values obtained for compound 1 and 2 following treatment at 24, 48 and 72 h were 0.660, 0.223, 0.370 microM and 0.677, 0.306, 0.360 microM, respectively. Cell morphological changes such as apoptotic and necrotic features were also been observed.

CONCLUSION

The compounds tested were found to give cytotoxic effect against chronic myelogenus leukemia (K-562) cell at a micromolar dose. Thus, further study on their specific mechanism of actions in the human cells should be carried out to elucidate their potential as an anticancer agent.

Cytotoxic effect of organotin(IV) benzylisopropyldithiocarbamate compounds on Chang liver cell and hepatocarcinoma HepG2 cell

Cancer is one of the main causes of mortality and morbidity in world. New compounds are currently being synthesized to combat this disease. The organotins are gaining more attention as anti-cancer agents due to their potent cytotoxicity properties. In this study, a series of newly synthesized organotins namely dimethyltin (IV) (compound 1), dibutyltin (IV) (compound 2) and triphenyltin (IV) benzylisopropyldithiocarbamate (compound 3) were assessed for their cytotoxic activities against human Chang liver cells and hepatocarcinoma HepG2 cells. The cytotoxicity of these organotins in both cells upon 24 h treatment was assessed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Compound 2 and 3 exhibited potent cytotoxic activities towards both cells where the IC50 values were less then 10 microM. The IC50 value for compound 2 was 2.5 microM in Chang liver cells and 7.0 microM in HepG2 cells whereas compound 3 exhibited an IC50 value of 1.5 microM in Chang liver cells and 2.5 microM in HepG2 cells. Therefore, compound 2 and 3 were more toxic against human Chang liver cells as compared to hepatocarcinoma HepG2 cells. Interestingly, compound 1 did not have any IC50 value in both cells and hence can be classified as non-toxic. In conclusion, organotin (IV) benzylisopropyldithiocarbamate with insertion of dibutyl and triphenyl functional group possess potent cytotoxicity properties. Structural modification of these compounds can be carried out in further studies to produce less or non toxic effects towards normal human cell.

Anticancer and cytotoxic effects of a triorganotin compound with 2-mercapto-nicotinic acid in malignant cell lines and tumor bearing Wistar rats

Nowadays, investigation for possible therapeutic applications of various metal-based drugs attracts the scientific interest worldwide. The triorganotin compound bis[triphenyltin(IV)](3-carboxy-pyridine-2-thionato) (SnMNA), was tested for its anti-proliferative and antitumor activities. Cytotoxic activity was assessed by Trypan blue and 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide assay (MTT). SnMNA exhibited potent cytotoxic effects against leiomyosarcoma cells (LMS) and human breast adenocarcinoma cells (MCF-7), which is 200 times stronger than that of cisplatin. Moreover, SnMNA induced significant apoptosis in LMS and MCF-7 cells characterized by flow cytometry analysis and DNA fragmentation. Acute and chronic toxicity studies on Wistar rats caused kidney and lung toxicity at a single dose of 80mg/kgBody Weight (BW) or four repeated doses of 8mg/kgBW once per week. Furthermore, antitumor activity studies on sarcoma bearing Wistar rats revealed that SnMNA complex at four repeated doses of 5.4mg/kgBW every three days prolonged mean survival time of the animal at 200% and decreased mean tumor growth rate (MTGR) compared to the control group (p<0.05). It is noteworthy to mention that the 30% (3 out of 10) of the bearing animals were totally cured. These findings indicate that SnMNA might be a promising new antitumor agent.

Anti-cancer drugs interfere with intracellular calcium signaling

(Neuro-)toxicity of metal and metal compounds is frequently highlighted. While specific metals or metal compounds are essential for cellular function, other metals are toxic and/or carcinogens. Metals can trigger accidental cell death in the form of necrosis, or activate programmed cell death in the form of apoptosis. The aim of anti-cancer therapy is induction of apoptosis in tumor cells. Therefore, there is an interesting twist in the toxicity of metals and metal compounds (e.g., arsenic trioxide, cisplatin); since they have a higher specificity to induce apoptosis in cancer cells (possibly due to the high turnover in these cells) they are used to cure some forms of cancer. A body of evidence suggests that second messengers, such as modulations in the intracellular calcium concentration, could be involved in metals induced toxicity as well as in the beneficial effects shown by anti-cancer drugs. Here we review the influence on calcium homeostasis induced by some metallic compounds: cisplatin, arsenic trioxide and trimethyltin chloride.

p53-dependent antiproliferative and antitumor effect of novel alkyl series of diorganotin(IV) compounds

PURPOSE

A series of diorganotin(IV) dichloride complexes of N-(2-pyridylmethylene)arylamine (nitrogen-chelating ligands) have been synthesized and characterized. The present study was carried out to investigate the comparative anti-proliferative and anti-tumor effect of Me(2)SnCl(2.)L(1) (OTC-1), Et(2)SnCl(2.)L(2) (OTC-2) and (n)Bu(2)SnCl. L(2) (OTC-3) in combination with X-rays (1.5 Gy).

METHOD

The cytotoxicity of these diorganotin(IV) compounds was studied in human peripheral lymphocytes and the antitumor activity was assessed in Dalton's lymphoma cells. The involvement of proteins that regulate cell cycle and apoptosis was investigated to elucidate the mechanism of their action.

RESULTS

5 mg kg(-1) of OTC-3 showed better antiproliferative and antitumor activity than OTC-1 and OTC-2, both as alone or in combination with X-rays. The maximum enhancement of exchange aberrations and the level of p53 and p16 proteins were observed in the OTC-3 treated samples. Upregulated expression of p53 caused a significant down-regulated transcriptionally repression of Survivin in OTC-3 treated human lymphocytes.

CONCLUSION

It could be possible that after treatment with either OTC-3 alone or in combination with X-rays the Dalton's lymphoma cells may die apoptotically after inducing initial delay in cell cycle and thereby survivality of mouse bearing Dalton's Lymphoma cells was increased significantly.

Cell proliferation inhibition and antitumor activity of novel alkyl series of diorganotin(IV) compounds

Diorganotin(IV) compounds, R2SnCl2 are often tetrahedral, and structurally resemble the active platinum compounds, i.e. cisplatin, and consequently a large number of such complexes have been tested for antitumor activity. A structural correlation with biological activity for diorganotin(IV) complexes has shown that active species are associated with complexes having Sn-N bonds longer than 2.39 A which in turn determines the formation of a tin-DNA complex. In view of these, a series of diorganotin(IV) dichloride complexes of N-(2-pyridylmethylene)arylamine (nitrogen-chelating ligands) has been synthesized and characterized on the basis of IR, NMR and 119Sn-Mössbauer studies. In the present study, an attempt was made to determine the comparative antiproliferative and antitumor effect of diorganotin(IV) complexes with different alkyl groups [Me2SnCl2.L1 (OTC-1), Et2SnCl2.L2 (OTC-2) and (n)Bu2SnCl2.L2 (OTC-3)]. The present study in human lymphocytes demonstrated that these diorganotin(IV) complexes could block the cell cycle progression and induce sister chromatid exchanges (SCEs) significantly, however, with respect to the induction of chromosome aberrations (CAs) it was very mild. Both the levels of p53 and p16 proteins were raised after diorganotin(IV) treatment and such induction was maximum in the OTC-3 treated samples. The antitumor activity was determined in accordance with the US National Cancer Institute (NCI) standard protocol for primary screening in Dalton's lymphoma that was maintained by serial intraperitoneal transplantation. The T/C (treated/control) value was increased (186% with OTC-3) when diorganotin(IV) was given after transplantation. The data suggest that the OTC-3 has better antiproliferative and antitumor activity and endogenous glutathione level has no influence on the effect of OTC-3.

Genotoxic effect of raw betel-nut extract in relation to endogenous glutathione levels and its mechanism of action in mammalian cells

The mutagenic and carcinogenic potency of betel-nut components is well established. This study was undertaken to determine the genotoxic potency of an aqueous extract of raw betel nut (AEBN) in relation to the endogenous glutathione (GSH) level in mouse bone marrow cells (BMC) and human peripheral blood lymphocytes (PBLs), and to find out whether arecoline (ARC), an alkaloid of betel nut, could generate reactive oxygen species (ROS) in these cells. It was observed that AEBN has genotoxic properties, which is further enhanced by depletion of endogenous GSH levels. However, the degree of enhancement varies with the type of parameter and cell system studied. The present data indicate that the generation of ROS by ARC could partially contribute to the induction of chromosomal aberrations (CAs), since the frequency of ARC-induced CAs was reduced either by post-treatment with superoxide dismutase (SOD) or in anoxic conditions. However, the induction of sister chromatid exchanges (SCEs) probably involves p53-dependent changes in cell proliferation and allowing some repair of DNA damage. The extent of damage for each parameter was higher when the mice were exposed to AEBN for 30 days than 5 days. Longer exposure showed higher level of p53 expression in mouse BMC, which could block the damaged cells from proliferation and allow the cells to repair the DNA damage.