Stereotactic Body Radiation and Interleukin-12 Combination Therapy Eradicates Pancreatic Tumors by Repolarizing the Immune Microenvironment

Over 80% of pancreatic ductal adenocarcinoma (PDA) patients are diagnosed with non-resectable late-stage disease that lacks effective neoadjuvant therapies. Stereotactic body radiation therapy (SBRT) has shown promise as an emerging neoadjuvant approach for treating PDA, and here, we report that its combination with local interleukin-12 (IL-12) microsphere (MS) immunotherapy results in marked tumor reduction and cures in multiple preclinical mouse models of PDA. Our findings demonstrate an increase of intratumoral interferon gamma (IFNγ) production following SBRT/IL-12 MS administration that initiates suppressor cell reprogramming and a subsequent increase in CD8 T cell activation. Furthermore, SBRT/IL-12 MS therapy results in the generation of systemic tumor immunity that is capable of eliminating established liver metastases, providing a rationale for follow-up studies in advanced metastatic disease.

Potent and Selective Cytotoxic and Anti-inflammatory Gold(III) Compounds Containing Cyclometalated Phosphine Sulfide Ligands

Four cycloaurated phosphine sulfide complexes, [Au{κ² -2-C₆ H₄ P(S)Ph₂ }₂ ][AuX₂ ] [X=Cl (2), Br (3), I (4)] and [Au{κ² -2-C₆ H₄ P(S)Ph₂ }₂ ]PF₆ (5), have been prepared and thoroughly characterized. The compounds were found to be stable under physiological-like conditions and showed excellent cytotoxicity against a broad range of cancer cell lines and remarkable cytotoxicity in 3D tumor spheroids. Mechanistic studies with cervical cancer (HeLa) cells indicated that the cytotoxic effects of the compounds involve the inhibition of thioredoxin reductase and induction of apoptosis through mitochondrial disruption. In vivo experiments in nude mice bearing HeLa xenografts showed that treatment with compounds 4 and 5 resulted in significant inhibition of tumor growth (35.8 and 46.9 %, respectively), better than that of cisplatin (29 %). The newly synthesized gold complexes were also evaluated for their in vitro and in vivo anti-inflammatory activity through the study of lipopolysaccharide (LPS)-activated macrophages and carrageenan-induced hind paw edema in rats, respectively.

Anticancer Ruthenium(III) Complexes and Ru(III)-Containing Nanoformulations: An Update on the Mechanism of Action and Biological Activity

The great advances in the studies on metal complexes for the treatment of different cancer forms, starting from the pioneering works on platinum derivatives, have fostered an increasingly growing interest in their properties and biomedical applications. Among the various metal-containing drugs investigated thus far, ruthenium(III) complexes have emerged for their selective cytotoxic activity in vitro and promising anticancer properties in vivo, also leading to a few candidates in advanced clinical trials. Aiming at addressing the solubility, stability and cellular uptake issues of low molecular weight Ru(III)-based compounds, some research groups have proposed the development of suitable drug delivery systems (e.g., taking advantage of nanoparticles, liposomes, etc.) able to enhance their activity compared to the naked drugs. This review highlights the unique role of Ru(III) complexes in the current panorama of anticancer agents, with particular emphasis on Ru-containing nanoformulations based on the incorporation of the Ru(III) complexes into suitable nanocarriers in order to enhance their bioavailability and pharmacokinetic properties. Preclinical evaluation of these nanoaggregates is discussed with a special focus on the investigation of their mechanism of action at a molecular level, highlighting their pharmacological potential in tumour disease models and value for biomedical applications.

α-Humulene inhibits hepatocellular carcinoma cell proliferation and induces apoptosis through the inhibition of Akt signaling

Hepatocellular carcinoma (HCC) is a prevalent malignancy and a leading cause of cancer-related mortality. α-Humulene (HML) is a natural 11-membered monocyclic terpene with three E-configured double bonds isolated from Eupatorium odoratum L. We recently showed that HML has significant anti-HCC activity in vitro and in vivo. We found that HML was cytotoxic to HCC cells and induced mitochondrial apoptosis of HCC cells, promoting caspase-3 activation and PARP cleavage. HCC cells show abnormal Akt signaling to resist apoptosis. Mechanistically, HML was found to inhibit Akt activation, subsequently decreasing GSK-3 and Bad phosphorylation, promoting apoptotic induction. HML also inhibited cell proliferation and enhanced apoptosis in HCC tumor xenografts further highlighting its activity in vivo. Although HML showed minimal cytotoxicity to normal hepatocytes, weight loss was observed in mice administered HML. Taken together, these data provide important and novel insights into the anti-HCC effects of HML through its ability to inhibit Akt, reduced HCC cell proliferation, and enhanced HCC cell apoptotic induction in vitro and in vivo.

Cancer survivors treated with platinum-based chemotherapy affected by ototoxicity and the impact on quality of life: a narrative synthesis systematic review

Objective: To identify any change in quality of life (QoL) caused by chemotherapy-induced toxicities, such as hearing loss and tinnitus, to provide information in order to improve services and aid clinicians in their decision-making. Design: This systematic review followed the preferred reporting items for systematic reviews and meta-analysis (PRISMA) checklist. The search terms were cancer, platinum-based chemotherapy, ototoxicity and "quality of life". Titles and abstracts, followed by full texts, were screened by two independent researchers. The relevant data were extracted and quality analysis was performed using the NIH Quality Assessment Tool. Study sample: About 308 titles and abstracts were screened, and 27 full-text articles were screened. Ten articles representing 11 studies were included in the review. Study design included cross-sectional studies, randomised control trials and longitudinal studies. Results: Diagnostic criteria consisted of audiograms, questionnaires and patient complaints. The study quality ranged from 21.43% to 85.71%. Overall results found that those treated with cisplatin had more hearing loss and tinnitus than those treated with other therapies. Furthermore, those with hearing loss and tinnitus were more likely to have a lower QoL. Conclusions: There is an urgent need to standardise diagnostics when investigating ototoxicity and its effect on QoL, particularly for research into risk factors, prevention and management.

A visible-light photoactivatable di-nuclear PtIV triazolato azido complex

A novel PtIV triazolato azido complex [3]-[N1,N3] has been synthesised via a strain-promoted double-click reaction (SPDC) between a PtIV azido complex (1) and the Sondheimer diyne (2). Photoactivation of [3]-[N1,N3] with visible light (452 nm) in the presence of 5'-guanosine monophosphate (5'-GMP) produced both PtIV and PtII 5'-GMP species; EPR spectroscopy confirmed the production of both azidyl and hydroxyl radicals. Spin-trapping of photogenerated radicals - particularly hydroxyl radicals - was significantly reduced in the presence of 5'-GMP.

Crystal structure, DNA crosslinking and photo-induced cytotoxicity of oxovanadium(IV) conjugates of boron-dipyrromethene

Cis-dichloro-oxovanadium(IV) complexes [VO(L¹/L²)Cl₂], where L¹ is N-(4-(5,5-difluoro-1,3,7,9-tetramethyl-5H-4ʎ⁴,5ʎ⁴-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborinin-10-yl)benzyl)-1-(pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine in 1 and L² is N-(4-(5,5-difluoro-2,8-diiodo-1,3,7,9-tetramethyl-5H-4ʎ⁴,5ʎ⁴-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborinin-10-yl)benzyl)-1-(pyridin-2-yl)-N-(pyridin-2-ylmethyl)methanamine in 2) having 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene as boron-dipyrromethene (BODIPY) appended dipicolylamine bases were prepared, characterized and their photocytotoxicity studied. X-ray crystal structure of 1 showed distorted octahedral geometry with a V^IVON₃Cl₂ core having Cl-V-Cl angle of 91.93(4)°. The complexes showed variable solution conductivity properties. They were non-electrolytes in dry DMF at 25 °C but showed 1:1 electrolytic behavior in an aqueous medium due to dissociation of one chloride ligand as evidenced from the mass spectral study. Complexes 1 and 2 showed absorption bands at 500 and 535 nm, respectively. The calf thymus DNA melting study revealed their interaction through DNA crosslinking on exposure to light which was further confirmed from the alkaline agarose gel electrophoresis using plasmid supercoiled pUC19 DNA. Complex 2 showed disruption of the mitochondrial membrane potential in the JC-1 (1,1',3,3'-tetraethyl-5,5',6,6'-tetrachloroimidacarbocyanine iodide) assay. The complexes were photocytotoxic in visible light (400-700 nm, power: 10 J cm^-2) in cervical cancer HeLa and breast cancer MCF-7 cells. Complex 2 having a photoactive diiodo‑boron-dipyrromethene moiety gave a singlet oxygen quantum yield (Φ_Δ) value of ~0.6. It showed singlet oxygen mediated apoptotic photodynamic therapy activity with remarkably low IC₅₀ (half maximal inhibitory concentration) value of ~0.15 μM. The cis-disposition of chlorides gave a cis-divacant 4-coordinate intermediate structure from the density functional theory (DFT) study thus mimicking the DNA crosslinking property of cisplatin.

A potent aminonaphthalimide platinum(IV) complex with effective antitumor activities in vitro and in vivo displaying dual DNA damage effects on tumor cells

A new aminonaphthalimide platinum(IV) complex was developed by incorporating aminonaphthalimide, a DNA intercalator, into the platinum(IV) system. This complex displayed potent antitumor activities against all tested tumor cell lines in vitro and showed great potential in overcoming drug resistance of cisplatin. Moreover, it remarkably inhibited the growth of CT26 xenografts in BALB/c mice without severe side effects in vivo. Then, the compound exhibited a dual DNA damage antitumor mechanism that it could interact with DNA in tetravalent form via the naphthalimide group to cause DNA lesion, and the further liberation of platinum(II) complex after reduction would induce remarkable secondary damage to DNA. Meanwhile, it caused cell apoptosis through an intrinsic apoptosis pathway by up-regulating the expression of caspase 3 and caspase 9.

Folic acid-modified ginsenoside Rg5-loaded bovine serum albumin nanoparticles for targeted cancer therapy in vitro and in vivo

BACKGROUND AND PURPOSE

Ginsenoside Rg5 (Rg5), a triterpene saponin, extracted from the natural herbal plant ginseng, is one of the most potent anticancer drugs against various carcinoma cells. However, the therapeutic potential of Rg5 is limited by its low solubility in water, poor bioavailability, and nontargeted delivery. Therefore, we prepared folic acid (FA)-modified bovine serum albumin (BSA) nanoparticles (FA-Rg5-BSA NPs) to improve the therapeutic efficacy and tumor targetability of Rg5.

METHODS

Various aspects of the FA-Rg5-BSA NPs were characterized, including size, polydispersity, zeta potential, morphology, entrapment efficiency (EE), drug loading (DL), in vitro drug release, thermal stability, in vitro cytotoxicity, cell apoptosis, cellular uptake, in vivo antitumor effects and in vivo biodistribution imaging.

RESULTS

The FA-Rg5-BSA NPs showed a particle size of 201.4 nm with a polydispersity index of 0.081, uniform spherical shape, and drug loading of 12.64±4.02%. The aqueous solution of FA-Rg5-BSA NPs had favorable stability for 8 weeks at 4°C. The FA-Rg5-BSA NPs dissolved under acidic conditions. Moreover, the Rg5-BSA NPs and FA-Rg5-BSA NPs had advanced anticancer activity compared with Rg5 in MCF-7 cells, while poor cytotoxicity was observed in L929 cells. The FA-Rg5-BSA NPs facilitated cellular uptake and induced apoptosis in MCF-7 cells. In addition, in an MCF-7 xenograft mouse model, the in vivo antitumor evaluation revealed that FA-Rg5-BSA NPs were more effective in inhibiting tumor growth than Rg5 and Rg5-BSA NPs. The in vivo real-time bioimaging study showed that the FA-Rg5-BSA NPs exhibited superior tumor accumulation ability.

CONCLUSION

The results suggested that FA-Rg5-BSA NPs could serve as a promising system to improve the antitumor effect of Rg5.

Anticancer Potential of Diiron Vinyliminium Complexes

Although ferrocene derivatives have attracted considerable attention as possible anticancer agents, the medicinal potential of diiron complexes has remained largely unexplored. Herein, we describe the straightforward multigram-scale synthesis and the antiproliferative activity of a series of diiron cyclopentadienyl complexes containing bridging vinyliminium ligands. IC₅₀ values in the low-to-mid micromolar range were determined against cisplatin sensitive and resistant human ovarian carcinoma (A2780 and A2780cisR) cell lines. Notable selectivity towards the cancerous cells lines compared to the non-tumoral human embryonic kidney (HEK-293) cell line was observed for selected compounds. The activity seems to be multimodal, involving reactive oxygen species (ROS) generation and, in some cases, a fragmentation process to afford monoiron derivatives. The large structural variability, amphiphilic character and good stability in aqueous media of the diiron vinyliminium complexes provide favorable properties compared to other widely studied classes of iron-based anticancer candidates.

Platinum(ii) complexes showing high cytotoxicity toward A2780 ovarian carcinoma cells

2,6-Bis(thiazol-2-yl)pyridines functionalized with 9-anthryl (L¹), 9-phenanthryl (L²), and 1-pyrenyl (L³) groups were used for the preparation of [Pt(Lⁿ)Cl]CF₃SO₃ (1-3). The constitution of the Pt(ii) complexes was determined by ¹H and ¹³C NMR spectroscopy, HR-MS spectrometry, elemental analysis and X-ray analysis (for (1)). The electrochemical and photophysical properties of [Pt(Lⁿ)Cl]CF₃SO₃ were compared with the behaviour of the Pt(ii) complexes with aryl-substituted 2,2':6',2''-terpyridine ligands. What is noteworthy is that the coordination ability of dtpy toward the Pt(ii) centre was investigated for the first time. All complexes were tested in vitro by MTS assay on four tumor cell lines, A2780 (ovarian carcinoma), HTC116 (colon rectal carcinoma), MCF7 (breast adenocarcinoma), and PC3 (prostate carcinoma) and on normal primary fibroblasts. Compounds (1-3) showed a dose dependent antiproliferative effect in the A2780 cell line with (3) > (2) > (1) and this loss of A2780 cell viability was due to a combination of an apoptotic cell death mechanism via mitochondria and autophagic cell death. Exposure to IC₅₀ concentration of (2) induced an increase in the number of apoptotic nuclei and a depolarization of the mitochondrial membrane which is consistent with the induction of apoptosis while exposure to IC₅₀ concentration of (3) showed an increase in the apoptotic nuclei with a slight hyperpolarization of the mitochondrial membrane that might indicate an initial step of apoptosis induction. The complexes (2) and (3) induce an increase in the production of intracellular ROS which is associated with the trigger of the apoptotic pathways. The ROS production was augmented by the presence of oxidants and correlated with an increase of oxygen radicals. The IC₅₀ of (2) and (3) (4.4 μM and 2.9 μM, respectively) was similar to the IC₅₀ of cisplatin (3.4 μM) in the A2780 cell line, which together with their low cytotoxicity in normal fibroblasts, demonstrates their potential for further studies.

Ruthenium Complex Induce Cell Death in G-415 Gallbladder Cancer Cells

PURPOSE

In this work, we present a recently developed ruthenium complex that shows anticancer activity in gallbladder cancer cells.

METHODS

After the synthesis of the new ruthenium complexes, the antiproliferative, cytotoxicity, and apoptosis activities were evaluated in vitro by the triple assay ApoTox-Glo. Then, the transcription levels of genes related to apoptosis were evaluated by real-time PCR (q-PCR).

RESULTS

The ruthenium complex, called Ru-UCN3, inhibits the proliferation of gallbladder cancer cells G-415 by means of apoptosis, which was demonstrated by the overexpression of the pro-apoptotic genes Puma, Diablo, and Caspasa-9 together with the repression of the anti-apoptotic genes Bcl-xL and Bcl-2. In addition, we found strong caspase 3/7 activity in the cells at 24 h of the Ru-UCN3 exposure, which was evaluated by the triple ApoTox-Glo assay.

CONCLUSION

The new ruthenium complexes evaluated had an inhibitory effect on G-415 cells. We think that Ru-UCN3 could be a promising anticancer agent, which should be explored with more in vitro and in vivo assays and probably with the chemical modulation of this molecule.

Paeonol induces cytoprotective autophagy via blocking the Akt/mTOR pathway in ovarian cancer cells

Paeonol (Pae), a phenolic acid compound isolated from the Moutan Cortex, was previously demonstrated to exert multiple anticancer effects. The rational control of autophagy has been considered a potential treatment strategy for epithelial ovarian cancer. However, whether Pae induces autophagy and the relationship between its antitumour activities and autophagy in epithelial ovarian cancer are still unclear. In this study, we found that Pae induced not only antiproliferation activity and apoptosis but also autophagy, and complete autophagic flux was observed in A2780 and SKOV3 cells. In addition, combination treatment with Pae and an autophagy inhibitor (3-methyladenine and hydroxychloroquine) showed significant synergetic effects on inhibiting cell viability and promoting apoptosis in vitro and in the A2780 xenograft model, without severe side effects, which was often had by cisplatin. These results indicate that autophagy induced by Pae has a cytoprotective role in both A2780 and SKOV3 cells. Mechanistically, we found that Pae inhibited the protein kinase B(Akt)/mammalian target of rapamycin (mTOR) pathway. Furthermore, when combined with the inhibitors MK2206 and rapamycin to inhibit Akt and mTOR kinase activity, Pae-induced autophagy was increased. Taken together, our results demonstrate that Pae induced cytoprotective autophagy by inhibiting the Akt/mTOR pathway in ovarian cancer cells. Thus, the strategy of combining Pae with an autophagy inhibitor to block Akt/mTOR-dependent autophagy could enhance the antitumour activity of Pae and warrants further application for the treatment of ovarian cancer.

Visible light-induced cytotoxicity studies on Co(ii) complexes having an anthracene-based curcuminoid ligand

Herein, two ternary cobalt(ii) complexes, namely [Co(9-accm)(phen)₂](OAc) (1) and [Co(9-accm)(dppz)₂](OAc) (2), where 9-accmH is 1,7-(di-9-anthracene-1,6-heptadiene-3,5-dione), phen is 1,10-phenanthroline and dppz is dipyrido[3,2-a:2',3'-c]phenazine, having an anthracene-based curcuminoid and phenanthroline bases were synthesized and fully characterized, and their in vitro photocytotoxicities were studied in cancer cells. To understand the role of the curcuminoid ligand 9-accm in photo-activated cytotoxicity, two control complexes, viz. [Co(dbm)(phen)₂](OAc) (3) and [Co(dbm)(dppz)₂](OAc) (4), where dbmH is 1,3-diphenyl-1,3-propanedione (dibenzoylmethane), were prepared and used for the control experiments. Complex 3 was structurally characterized by X-ray crystallography. The complexes displayed a quasi-reversible Co(i)/Co(ii) redox couple at ∼-1.1 V and an irreversible Co(ii)/Co(iii) couple at ∼1.3 V vs. Ag/AgCl in DMF-0.1 M [Buⁿ₄N](ClO₄). Highly intense 9-accm ligand-centred bands were observed at ∼250-450 nm, which masked the Co(ii)-based weak d-d bands in the DMF-Tris-HCl buffer (1 : 9 v/v). The complexes displayed a significant binding propensity for calf-thymus (ct) DNA with binding constants in the range from (2.42 ± 0.10) × 10⁵ to (3.24 ± 0.13) × 10⁶ M^-1. They also showed a moderate binding affinity for human serum albumin (HSA), displaying K_b values in the order of ∼10⁴-10⁵ M^-1. The complexes 1 and 2 showed prodigious photoenhanced cytotoxicity in human cervical cancer (HeLa) and breast cancer (MCF-7 and MDA-MB-231) cells with low dark toxicity, whereas they were non-toxic to immortalized lung epithelial normal cells (HPL1D). Flow cytometric studies showed a time-dependent uptake of the complexes 1 and 2 in HeLa cells. The complexes generated reactive oxygen species (ROS) upon excitation with low energy visible light, thereby killing the cancer cells. The results from DAPI staining, AO/EB dual staining and Annexin-V-FITC experiments suggested that the complexes induce cell death primarily via an apoptotic mechanism in HeLa cells.

Cyclometallated Au(iii) dithiocarbamate complexes: synthesis, anticancer evaluation and mechanistic studies

A series of cationic mixed cyclometallated (C^N)Au(iii) dithiocarbamate complexes has been synthesized in good yields [HC^N = 2-(p-t-butylphenyl)pyridine]. The crystal structure of [(C^N)AuS2CNEt2]PF6 (3) has been determined. The cytotoxic properties of the new complexes have been evaluated in vitro against a panel of human cancer cell lines and healthy cells and compared with a neutral mixed (C^C)Au(iii) dithiocarbamate complex (C^C = 4,4'-di-t-butylbiphenyl-2,2'-diyl). The complexes appeared to be susceptible to reduction by glutathione but were stable in the presence of N-acetyl cysteine. The potential mechanism of action of this class of compounds has been investigated by measuring the intracellular uptake of some selected complexes, by determining their interactions with higher order DNA structures, and by assessing the ability to inhibit thioredoxin reductase. The complexes proved unable to induce the formation of reactive oxygen species. The investigations add to the picture of the possible mode of action of this class of complexes.

A polysaccharide from Huaier ameliorates cisplatin nephrotoxicity by decreasing oxidative stress and apoptosis via PI3K/AKT signaling

Cisplatin (CP), a common chemotherapy drug used in treatment of malignant tumors. Due to various side effects such as nephrotoxicity (kidney damage), it's efficiency and therapeutic application are limited. This study focuses on finding a suitable drug that would attenuate the side effects like kidney damage, caused by CP. Huaier polysaccharide (HP-1), an extraction of Trametes robiniophila Murr, with a molecular weight of 3 × 10⁴ Da. Previous studies have shown that HP-1, exhibits anti-tumor potential and immunomodulatory effects. We hypothesized that HP-1 has the effect of attenuating the nephrotoxicity caused by CP chemotherapy and protecting renal function. Through our experiments, we observed that HP-1 can attenuate the level of oxidative stress, inflammation and mitochondrial dysfunction, thereby reducing kidney damage. In vitro, we observed that HP-1 significantly inhibits CP-induced renal tubular cell apoptosis and cell cycle arrest. In addition, HP-1 also affects the expression level of the protein by regulating the PI3K/Akt/mTOR signaling pathway and thus attenuates the side effects induced by cisplatin. Therefore, HP-1 may be a potential drug for preventing CP-induced renal damage.

Capsaicinoids enhance chemosensitivity to chemotherapeutic drugs

Cytotoxic chemotherapy is the mainstay of cancer treatment. Conventional chemotherapeutic agents do not distinguish between normal and neoplastic cells. This leads to severe toxic side effects, which may necessitate the discontinuation of treatment in some patients. Recent research has identified key molecular events in the initiation and progression of cancer, promoting the design of targeted therapies to selectively kill tumor cells while sparing normal cells. Although, the side effects of such drugs are typically milder than conventional chemotherapies, some off-target effects still occur. Another serious challenge with all chemotherapies is the acquisition of chemoresistance upon prolonged exposure to the drug. Therefore, identifying supplementary agents that sensitize tumor cells to chemotherapy-induced apoptosis and help minimize drug resistance would be valuable for improving patient tolerance and response to chemotherapy. The use of effective supplementary agents provides a twofold advantage in combination with standard chemotherapy. First, by augmenting the activity of the chemotherapeutic drug it can lower the dose needed to kill tumor cells and decrease the incidence and severity of treatment-limiting side effects. Second, adjuvant therapies that lower the effective dose of chemotherapy may delay/prevent the development of chemoresistance in tumors. Capsaicinoids, a major class of phytochemical compounds isolated from chili peppers, have been shown to improve the efficacy of several anti-cancer drugs in cell culture and animal models. The present chapter summarizes the current knowledge about the chemosensitizing activity of capsaicinoids with conventional and targeted chemotherapeutic drugs, highlighting the potential use of capsaicinoids in novel combination therapies to improve the therapeutic indices of conventional and targeted chemotherapeutic drugs in human cancers.

Iridium(III) Complexes Targeting Apoptotic Cell Death in Cancer Cells

Targeting apoptosis is a principal strategy in the design of anticancer drugs. In recent years, non-platinum-based scaffolds have been exploited as viable candidates for the exploitation of anticancer agents with potentially lower toxicity than the widely used cisplatin analogues. This review highlights the latest advances in developing iridium(III) complexes as anticancer agents that act particularly via targeting apoptotic cell death in cancer cells.

Additive Pharmacological Interaction between Cisplatin (CDDP) and Histone Deacetylase Inhibitors (HDIs) in MDA-MB-231 Triple Negative Breast Cancer (TNBC) Cells with Altered Notch1 Activity-An Isobolographic Analysis

The aim of this study was to investigate the influence of the Notch1 activity level on the pharmacological interaction between cisplatin (CDDP) and two histone deacetylase inhibitors (HDIs)-valproic acid (VPA) and vorinostat (SAHA) in the triple negative breast cancer (TNBC) cells. Stable breast cancer (BC) cell lines with increased and decreased activity of Notch1 were generated using a transfection method. The type of interaction between CDDP and the HDIs was determined by isobolographic analysis of cell proliferation in MDA-MB-231 cells with differential levels of Notch1 activity in vitro. The combination of CDDP/SAHA and CDDP/VPA in the MDA-MB-231 triple negative breast cancer (TNBC) cells with increased activity of Notch1, as well as CDDP/VPA in the MDA-MB-231 cells with decreased activity of Notch1, yielded an additive interaction, whereas additivity with a tendency towards antagonism was observed for the combination of CDDP/SAHA in MDA-MB-231 cells with the decreased activity of Notch1. Our studies demonstrated that SAHA and VPA might be considered as potential therapeutic agents in combination therapy with CDDP against TNBC with altered Notch1 activity.

Endowment of pH Responsivity to Anticancer Peptides by Introducing 2,3-Diaminopropionic Acid Residues

Endowment of pH responsivity to anticancer peptides is a promising approach to achieve better selectivity to cancer tissues. In this research, a template peptide was designed based on magainin 2, an antimicrobial peptide with anticancer activity, and a series of peptides were designed by replacing different numbers of lysine with the unnatural amino acid, 2,3diaminopropionic acid (Dap), which has a positive charge at weakly acidic pH in cancer tissues, but is neutral at physiological pH 7.4. These Dap-containing peptides are expected to interact more strongly with tumor cells than with normal cells because 1) weakly acidic conditions form in tumors, and 2) the membrane of tumor cells is more anionic than that of normal cells. Although all examined peptides showed potent cytotoxicities to multidrug-resistant cancer cells at a weakly acidic pH (ED₅₀ ≈5 μm), the toxicity decreased with an increase in the number of Dap at pH 7.4 (8 Dap residues resulted in ED₅₀ ≈60 μm). Furthermore, the introduction of Dap reduced cytotoxicity against normal cells. Thus, Dap led to significantly improved cancer targeting due to a pH-dependent charge shift. Fluorescence imaging and model membrane experiments supported this charge-shift model.

Improving the anticancer activity of platinum(iv) prodrugs using a dual-targeting strategy with a dichloroacetate axial ligand

Four novel platinum(iv) complexes, characteristic of DCA/TFA and with chloride ions as axial ligands, were designed and synthesized. This type of platinum(iv) complexes 1a–2b exhibited significant cytotoxic activity, and the cytotoxicity of 1b was the greatest among these four complexes, which was 20.61 fold and 7.65 fold higher than that of cisplatin against HepG-2 and NCI-H460 cancer cells, respectively. The result from the apoptosis assay of 1b was consistent with the result from the cytotoxicity assay. In addition, complexes 1a and 1b induced cell cycle arrest at the S phase on HepG-2 cells. Taken together, our data showed that Pt(iv) complex 1b released the corresponding Pt(ii) complex and DCA, and induced apoptosis as well as disruption of the mitochondrial membrane potential, establishing Pt(iv) complex 1b as a potential dual-targeting anticancer agent.

Complex 1b could release complex B and DCA, playing a dual-targeting anti-tumor effect against cancer cells, targeting nuclear DNA and mitochondria, respectively.

Determination of oxaliplatin enantiomers at attomolar levels by capillary electrophoresis connected with inductively coupled plasma mass spectrometry

The aim of this study was to develop a method for the separation of oxaliplatin enantiomers at attomolar concentration levels. A combination of capillary electrophoresis and inductively coupled plasma mass spectrometry was chosen due to their unique characteristics, including fast and easy modification of separation selectivity, and significant limits of detection and linearity. In the first step, we optimized conditions for the separation of oxaliplatin enantiomers including background electrolyte composition and concentration, pH, and type and concentration of the chiral selector. Under optimal conditions, sodium borate buffer pH 9.5, ionic strength 40 mmol L^-1, with 60 mg mL^-1 sulfated β-cyclodextrin, separation was obtained with a resolution of 2.0. This electrolyte system was then used in the 'in-house' connection of capillary electrophoresis with inductively coupled plasma mass spectrometer. In this instance, separation lasted for 9.5 min. Calibrations were linear in the range of 0.1-500 μg mL^-1 with R² of 0.9999. LOD and LOQ values were of 64 ng mL^-1 and 116 ng mL^-1 of oxaliplatin, respectively. This represents detection of 49 fg or 125 attomol of oxaliplatin enantiomers in the capillary electrophoresis injected sample zone. Finally, the method was successfully applied for detection of oxaliplatin enantiomers in spiked urine samples.

Oleanolic acid attenuates cisplatin-induced nephrotoxicity in mice and chemosensitizes human cervical cancer cells to cisplatin cytotoxicity

Oleanolic acid (OA) is a natural triterpenoid that possesses numerous beneficial health effects such as antioxidant, anti-inflammatory and anti-apoptotic activities. In this study, we investigated the therapeutic effect of OA (10 and 40 mg/kg) on cisplatin (CP)-induced (13 mg/kg) nephrotoxicity. Treatment with OA 40 mg/kg once daily for 2 days, 48 h after CP-intoxication, ameliorated the increased serum markers and histological features of kidney injury. CP administration increased renal expression of antioxidant and anti-inflammatory markers, which was reduced by OA. The increase in proapoptotic caspase-3 and -9 activations, with concomitant increase in poly (ADP-ribose) polymerase (PARP) cleavage, were dose-dependently inhibited by OA. Treatment with OA also ameliorated microtubule-associated protein 1A/1B-light chain 3B (LC3B)-II and autophagy-related protein (Atg) 5 expression induced by CP. The suppression of CP-induced oxidative stress, apoptosis, autophagy and inflammatory response by OA coincided with the inhibition of extracellular-regulated kinase (ERK) 1/2, signal transducer and activator of transcription (STAT) 3 and nuclear factor-kappa B (NF-κB). Interestingly, OA increased CP cytotoxicity in HeLa cervical cancer cells by inducing cytotoxic autophagy. The chemosensitization of HeLa cells to CP suggests a potential beneficial effect of OA in cervical cancer patients due to reduced CP dosage requirements, which requires further investigation.

Mitochondrial Involvement in Cisplatin Resistance

Cisplatin is one of the worldwide anticancer drugs and, despite its toxicity and frequent recurrence of resistance phenomena, it still remains the only therapeutic option for several tumors. Circumventing cisplatin resistance remains, therefore, a major goal for clinical therapy and represents a challenge for scientific research. Recent studies have brought to light the fundamental role of mitochondria in onset, progression, and metastasis of cancer, as well as its importance in the resistance to chemotherapy. The aim of this review is to give an overview of the current knowledge about the implication of mitochondria in cisplatin resistance and on the recent development in this research field. Recent studies have highlighted the role of mitochondrial DNA alterations in onset of resistance phenomena, being related both to redox balance alterations and to signal crosstalk with the nucleus, allowing a rewiring of cell metabolism. Moreover, an important role of the mitochondrial dynamics in the adaptation mechanism of cancer cells to challenging environment has been revealed. Giving bioenergetic plasticity to tumor cells, mitochondria allow cells to evade death pathways in stressful conditions, including chemotherapy. So far, even if the central role of mitochondria is recognized, little is known about the specific mechanisms implicated in the resistance. Nevertheless, mitochondria appear to be promising pharmacological targets for overcoming cisplatin resistance, but further studies are necessary.

Diplatinum(II) Catecholate of Photoactive Boron-Dipyrromethene for Lysosome-Targeted Photodynamic Therapy in Red Light

The binuclear platinum(II) boron-dipyrromethene (BODIPY) complex [{Pt(dach)}₂(μ-Dcrb)] (DP), where dach is 1,2-diaminocyclohexane and H₄Dcrb is a morpholine-conjugated BODIPY-linked dicatechol bridging ligand, was prepared for lysosome organelle targeting and near-IR (NIR) light (600-720 nm) induced photocytotoxic activity. The platinum complex [Pt(dach)(cat)] (CP), where H₂cat is catechol, was synthesized and used as a control complex without bearing the BODIPY unit. The complex DP displayed a band at 660 nm (ε = 2.1 × 10⁴ M^-1 cm^-1) in the red region of the UV-visible spectrum recorded in 10% dimethyl sulfoxide/Dulbecco's Modified Eagle's Medium (DMSO/DMEM, pH 7.2). The complex DP and the BODIPY ligand displayed emission in 10% DMSO-DMEM (pH 7.2) giving an λ_em value of 668 nm (λ_ex = 650 nm) with a Φ_F value of 0.02 for DP and 0.16 for H₄Dcrb (Φ_F, fluorescence quantum yield). Titration experiments using 1,3-diphenylisobenzofuran (DPBF) indicated that the complex DP and H₄Dcrb on irradiation with near-IR light of 600-720 nm generated singlet oxygen (¹O₂) as the ROS (reactive oxygen species). The complex DP showed significant lysosomal localization and remarkable apoptotic photodynamic therapy (PDT) effects, giving half-maximal inhibitory concentration values (IC₅₀) within 0.6-3.4 μM in HeLa cervical cancer, A549 lung cancer, and MDA-MB231 multidrug resistant cancer cells, while being essentially nontoxic in the dark and in the HPL1D immortalized lung epithelial normal cells. The acridine orange assay using A549 cells showed lysosomal membrane permeabilization by the complex DP under near-IR light (600-720 nm). This complex on near-IR light (600-720 nm) activation in A549 cells induced apoptotic cell death, as observed from an Annexin-V FITC assay.

Antiproliferative Activity of Pt(IV) Conjugates Containing the Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) Ketoprofen and Naproxen †

Cisplatin and several non-steroidal anti-inflammatory drugs (NSAIDs) have been proven to act synergistically or at least additively on several tumor cell lines. Dual-action cisplatin-based Pt(IV) combos containing ketoprofen and naproxen offer good antiproliferative performance on a panel of human tumor cell lines, including a malignant pleural mesothelioma (MPM) one, a very chemoresistant tumor. The main reason of the increased activity relies on the enhanced lipophilicity of these Pt(IV) conjugates that in turn promotes increased cellular accumulation. A quick Pt(IV)→Pt(II) reduction generates the active cisplatin metabolite. The NSAID adjuvant action seems to be almost independent from cyclooxygenase-2 (COX-2) expression in the tumor cells under investigation (lung A-549, colon HT-29, HCT 116, SW480, ovarian A2780, and biphasic MPM MSTO-211H), but it seems to rely (at least in part) on the activation of the NSAID activated gene, NAG-1 (a member of the transforming growth factor beta, TGF-β, superfamily), which has been suggested to be involved in NSAID antiproliferative activity.

Synthesis and in-depth studies on the anticancer activity of novel palladacyclopentadienyl complexes stabilized by N-Heterocyclic carbene ligands

New palladacyclopentadienyl complexes with bis-N-heterocyclic carbenes as spectator ligands have been synthesized and exhaustively characterized. The crystal structure of complex 1a has been also determined by X-ray diffraction analysis. Their in vitro cytotoxicity and that of other palladacyclopentadienyl derivatives coordinating different ancillary ligands has been determined against different cancer cell lines. Many complexes have shown an antiproliferative activity toward tumor cells often definitely better than cisplatin, whereas they have resulted practically inactive against the non-cancer MRC-5 cell line. The mechanism of action of bis-NHC derivative 1a, particularly active against ovarian cancer cell lines was studied in depth. Through a longitudinally analysis, it is shown that compound 1a induces apoptosis via DNA damage and release of cytochrome C. We propose compound 1a as a powerful and specific drug for the therapy of a deadly disease such as high grade serous ovarian cancer.

Role of oxidative stress in cardiotoxicity of antineoplastic drugs

Tumors and heart disease are two of the leading causes of human death. With the development of anti-cancer therapy, the survival rate of cancer patients has been significantly improved. But at the same time, the incidence of cardiovascular adverse events caused by cancer treatment has also been considerably increased, such as arrhythmia, left ventricular (LV) systolic and diastolic dysfunction, and even heart failure (HF), etc., which seriously affects the quality of life of cancer patients. More importantly, the occurrence of adverse events may lead to the adjustment or the cessation of anti-cancer treatment, which affects the survival rate of patients. Understanding the mechanism of cardiotoxicity (CTX) induced by antineoplastic drugs is the basis of adequate protection of the heart without impairing the efficacy of antineoplastic therapy. Based on current research, a large amount of evidence has shown that oxidative stress (OS) plays an essential role in CTX induced by antineoplastic drugs and participates in its toxic reaction directly and indirectly. Here, we will review the mechanism of action of OS in cardiac toxicity of antineoplastic drugs, to provide new ideas for researchers, and provide further guidance for clinical prevention and treatment of cardiac toxicity of anti-tumor drugs in the future.

Meta-analysis comparing incidence of grade 3-4 neutropenia with ALK inhibitors and chemotherapy in patients with non-small-cell lung cancer

Aim: This meta-analysis compared incidence of grade 3-4 neutropenia with ALK inhibitors versus chemotherapy in patients with non-small-cell lung cancer. Materials & methods: PubMed/MEDLINE was searched to identify Phase II and III randomized clinical trials published up to 25 October 2018. Summary incidence, relative risk and corresponding 95% CIs were calculated for grade 3-4 neutropenia. Results: Five randomized clinical trials were included. Relative risk (95% CI) of developing grade 3-4 neutropenia with ALK inhibitor versus chemotherapy was 0.27 (0.07-1.06). Probabilities of developing grade 3-4 neutropenia were 6.56 and 14.19%, respectively; no significant difference was found. Conclusion: In patients with non-small-cell lung cancer, incidence of grade 3-4 neutropenia with ALK-targeted therapy is not significantly different compared with chemotherapy.

Effect of lipid metabolism disorder on liver function in patients with malignant tumors after chemotherapy: a case-control study

BACKGROUND

This study aims to investigate the effect of lipid metabolism disorder on liver function in patients with malignant tumors after chemotherapy.

METHOD

A total of 428 patients with malignant tumors with normal liver function in our hospital between May 2013 to June 2018 were divided into an observation group (lipid metabolism disorder, n = 265) and control group (normal lipid metabolism, n = 163). The lipid metabolism levels and liver damage of the two groups were compared before and after chemotherapy.

RESULTS

No significant differences in age, gender, body mass index, tumor types, history of surgery, levels of alanine aminotransferase (ALT; an indicator of liver function), and chemotherapy regimen were observed between the two groups. However, the observation group showed increased levels of total cholesterol (P = 0.000), triglycerides (P = 0.000), and low-density lipoprotein (P = 0.01), as well as decreased levels of high-density lipoprotein (P = 0.000) before chemotherapy compared with the control group. Furthermore, patients with lipid metabolism disorders were more likely to develop abnormal liver function after chemotherapy. Moreover, mixed lipid metabolism disorder was more likely to cause severe liver damage after chemotherapy. Additionally, the number of patients with lipid metabolism disorders after chemotherapy (n = 367) was significantly increased compared with before chemotherapy (n = 265) (P < 0.01), indicating that chemotherapy might induce or aggravate an abnormal lipid metabolism.

CONCLUSIONS

After receiving chemotherapy, patients with malignant tumors presenting lipid metabolism disorders are more prone to liver damage and lipid metabolism disorders than patients with a normal lipid metabolism.

American Ginseng (Panax quinquefolium L.) as a Source of Bioactive Phytochemicals with Pro-Health Properties

Panax quinquefolium L. (American Ginseng, AG) is an herb characteristic for regions of North America and Asia. Due to its beneficial properties it has been extensively investigated for decades. Nowadays, it is one of the most commonly applied medical herbs worldwide. Active compounds of AG are ginsenosides, saponins of the glycosides group that are abundant in roots, leaves, stem, and fruits of the plant. Ginsenosides are suggested to be primarily responsible for health-beneficial effects of AG. AG acts on the nervous system; it was reported to improve the cognitive function in a mouse model of Alzheimer's disease, display anxiolytic activity, and neuroprotective effects against neuronal damage resulting from ischemic stroke in animals, demonstrate anxiolytic activity, and induce neuroprotective effects against neuronal damage in ischemic stroke in animals. Administration of AG leads to inhibition of hypertrophy in heart failure by regulation of reactive oxygen species (ROS) in mice as well as depletion of cardiac contractile function in rats. It also has an anti-diabetic and anti-obesity potential as it increases insulin sensitivity and inhibits formation of adipose tissue. AG displays anti-cancer effect by induction of apoptosis of cancer cells and reducing local inflammation. It exerts antimicrobial effects against several pathogenic strains of bacteria. Therefore, AG presents a high potential to induce beneficial health effects in humans and should be further explored to formulate precise nutritional recommendations, as well as to assess its value in prevention and therapy of some disorders, including cancer.

Immunoepigenetics Combination Therapies: An Overview of the Role of HDACs in Cancer Immunotherapy

Long-standing efforts to identify the multifaceted roles of histone deacetylase inhibitors (HDACis) have positioned these agents as promising drug candidates in combatting cancer, autoimmune, neurodegenerative, and infectious diseases. The same has also encouraged the evaluation of multiple HDACi candidates in preclinical studies in cancer and other diseases as well as the FDA-approval towards clinical use for specific agents. In this review, we have discussed how the efficacy of immunotherapy can be leveraged by combining it with HDACis. We have also included a brief overview of the classification of HDACis as well as their various roles in physiological and pathophysiological scenarios to target key cellular processes promoting the initiation, establishment, and progression of cancer. Given the critical role of the tumor microenvironment (TME) towards the outcome of anticancer therapies, we have also discussed the effect of HDACis on different components of the TME. We then have gradually progressed into examples of specific pan-HDACis, class I HDACi, and selective HDACis that either have been incorporated into clinical trials or show promising preclinical effects for future consideration. Finally, we have included examples of ongoing trials for each of the above categories of HDACis as standalone agents or in combination with immunotherapeutic approaches.

Fuplatin: An Efficient and Low-Toxic Dual-Prodrug

As FDA-approved chemotherapeutic agents, cisplatin, oxaliplatin, and 5-fluorouracil are widely used in clinic but limited by severe side-effects. To ameliorate their respective defects, a series of "dual-prodrug" by linking oxoplatin and 5-FU were designed and synthesized. The assembled compounds 10-17, named Fuplatin, exhibited much higher cytotoxicity against the tested cancer cells while lower cytotoxicity toward the human normal lung cells than free drugs or their combinations. Among them, 14 enhanced cellular accumulation with 62- and 825-fold amount of oxaliplatin and 8 at 9 h, respectively, significantly induced DNA damage and cell apoptosis, and inhibited migration and invasion in HCT-116 cells. Compound 14 arrested the cell cycle at S and G2 phases and up-regulated thymidylate synthase and p53, consistent with the results of the combination, suggesting 14 adopted a collaborative mode of 5-FU and oxaliplatin to kill cancer cells. In vivo, compound 14 showed high antitumor effect and no observable toxicity in NOD/SCID mice bearing HCT-116 tumors.

Modulating the Chemical and Biological Properties of Cancer Stem Cell-Potent Copper(II)-Nonsteroidal Anti-Inflammatory Drug Complexes

Copper(II) complexes bearing nonsteroidal anti-inflammatory drugs (NSAIDs) are known to potently kill cancer stem cells (CSCs), a subpopulation of tumour cells with high metastatic and relapse fidelity. One of the major disadvantages associated to these copper(II) complexes is their instability in the presence of strong cellular reductants (such as ascorbic acid). Here we present a biologically stable copper(II)-NSAID complex containing a bathocuproinedisulfonic acid disodium ligand and two indomethacin moieties, Cu(bathocuproinedisulfonic acid disodium)(indomethacin)₂, 2. The copper(II) complex, 2 kills bulk breast cancer cells and breast CSC equally (in the sub-micromolar range) and displays very low toxicity against non-tumorigenic breast and kidney cells (IC₅₀ value > 100 µM). Three-dimensional cell culture studies show that 2 can significantly reduce the number and size of breast CSC mammospheres formed (from single suspensions) to a similar level as salinomycin (an established anti-breast CSC agent). The copper(II) complex, 2 is taken up reasonably by breast CSCs and localises largely in the cytoplasm (>90%). Cytotoxicity studies in the presence of specific inhibitors suggest that 2 induces CSC death via a reactive oxygen species (ROS) and cyclooxygenase isoenzyme-2 (COX-2) dependent apoptosis pathway.

Challenges and Chances in the Preclinical to Clinical Translation of Anticancer Metallodrugs

Despite being “sentenced to death” for quite some time, anticancer platinum compounds are still the most frequently prescribed cancer therapies in the oncological routine and recent exciting news from late-stage clinical studies on combinations of metallodrugs with immunotherapies suggest that this situation will not change soon. It is perhaps surprising that relatively simple molecules like cisplatin, discovered over 50 years ago, are still widely used clinically, while none of the highly sophisticated metal compounds developed over the last decade, including complexes with targeting ligands and multifunctional (nano)formulations, have managed to obtain clinical approval. In this book chapter, we summarize the current status of ongoing clinical trials for anticancer metal compounds and discuss the reasons for previous failures, as well as new opportunities for the clinical translation of metal complexes.

Tandem mass spectrometry characterization of a conjugate between oleuropein and hydrated cis-diammineplatinum(II)

RATIONALE

Oleuropein (Ole) has been claimed to mitigate cisplatin (CP)-induced acute injury in kidney and liver of mice. In vitro reactivity of hydrated CP species with Ole, and an Ole metabolite, hydroxytyrosol (HT), is of great interest as the preliminary step for gathering in vivo information on the possible physiological role of the Ole/HT-cis-diammineplatinum(II) (Ole/HT-cis-DAP) conjugate.

METHODS

Reversed-phase liquid chromatography coupled to electrospray ionization mass spectrometry using a linear ion trap instrument (RPLC/ESI-MS) and tandem mass (MS/MS) measurements, both in positive and negative ion mode, revealed the molecular identity of platinum-based conjugates.

RESULTS

The Ole-cis-DAP conjugate (i.e., C₂₅ H₃₆ N₂ O₁₃ Pt^II ) features two cis-ammine non-leaving ligands and a bidentate catechol ligand moiety belonging to Ole; the coordination of the central Pt(II) is square-planar with non-equivalent bond angles compared with the ideal arrangement of 90°. HT, the free Ole metabolite excreted in human urine, acts as bidentate O,O-donor ligand of cis-DAP as well.

CONCLUSIONS

The first evidence, together with structural information, is provided about the in vitro formation of a conjugate between cis-DAP and Ole or its urinary metabolite HT. Presuming that such conjugates are also generated in vivo, the mechanisms by which they might contribute to reduce CP toxicity remain to be elucidated.