Cisplatin: The first metal based anticancer drug

Novel recognition mechanism based on oxidative addition of Pt(II) complex-based luminescent probes for hypochlorite ion detection

Platinum(II) complexes are the most commonly used anticancer drugs and potential optical materials, but the detectability of Pt(II) complex-based probes is seldom reported. In our previous work, a tetradentate Pt(II) complex Pt-CHO was utilised as a 'turn-off' probe to detect ClO^- and image cancer cells. However, the recognition mechanism has not been completely clarified and there are still doubts. In this work, three Pt(II) complexes, Pt-H, Pt-CHO and Pt-COOH, were developed to elucidate the mechanism of this class of complexes and refine their property studies. As a result, the UV-visible absorption and luminescence emission experiments, as well as the mass spectrum, proved that the oxidation of Pt(II) to Pt(IV) was the real reason for luminescence quenching, which has nothing to do with aldehyde groups. This first reported mechanism introduces a new type of ClO^- probe based on Pt(II) complexes, thereby expanding the application fields of platinum complexes. Moreover, the quantum yield measurements, the effect of biomolecules and reversibility were studied to improve the properties of the probes. Theoretical calculations were used to gain an in-depth understanding of optical characteristics and related mechanisms. The cell imaging of RAW264.7 cells under endogenous ClO^- proved the potential of the probes in bioimaging.

N-Heterocyclic Carbene Iron Complexes as Anticancer Agents: In Vitro and In Vivo Biological Studies

Cisplatin and its derivatives are commonly used in chemotherapeutic treatments of cancer, even though they suffer from many toxic side effects. The problems that emerge from the use of these metal compounds led to the search for new complexes capable to overcome the toxic side effects. Here, we report the evaluation of the antiproliferative activity of Fe(II) cyclopentadienyl complexes bearing n-heterocyclic carbene ligands in tumour cells and their in vivo toxicological profile. The in vitro antiproliferative assays demonstrated that complex Fe1 displays the highest cytotoxic activity both in human colorectal carcinoma cells (HCT116) and ovarian carcinoma cells (A2780) with IC₅₀ values in the low micromolar range. The antiproliferative effect of Fe1 was even higher than cisplatin. Interestingly, Fe1 showed low in vivo toxicity, and in vivo analyses of Fe1 and Fe2 compounds using colorectal HCT116 zebrafish xenograft showed that both reduce the proliferation of human HCT116 colorectal cancer cells in vivo.

Drug resistance: from bacteria to cancer

The phenomenon of drug resistance has been a hindrance to therapeutic medicine since the late 1940s. There is a plethora of factors and mechanisms contributing to progression of drug resistance. From prokaryotes to complex cancers, drug resistance is a prevailing issue in clinical medicine. Although there are numerous factors causing and influencing the phenomenon of drug resistance, cellular transporters contribute to a noticeable majority. Efflux transporters form a huge family of proteins and are found in a vast number of species spanning from prokaryotes to complex organisms such as humans. During the last couple of decades, various approaches in analyses of biochemistry and pharmacology of transporters have led us to understand much more about drug resistance. In this review, we have discussed the structure, function, potential causes, and mechanisms of multidrug resistance in bacteria as well as cancers.

Research Progress on the Functions and Mechanism of circRNA in Cisplatin Resistance in Tumors

Cisplatin is a common chemotherapeutic drug that has been used to treat of numerous tumors, including testicular, lung, bladder, ovarian, liver and head and neck cancers. Although clinical chemotherapy based on cisplatin has shown a remarkable therapeutic effect, the resistance to cisplatin becomes increasingly obvious as a patient uses it for a prolonged period. It not only affects the prognosis of these tumors, but also causes the recurrence of cancer and decreases the overall survival rate. The development of cisplatin resistance involves several mechanisms, including DNA damage repair, ATP-binding cassette (ABC) transporter, autophagy, cancer stem cells (CSCs), epithelial-mesenchymal transition (EMT), and other related signaling pathways. Interestingly, these mechanisms have been found to be influenced by circular RNAs (circRNAs) to regulate tumor proliferation, invasion, chemosensitivity, and other biological behaviors in the tumor microenvironment (TME). In recent years, circRNAs in cisplatin resistance in tumors, especially lung cancer and gastric cancer, have gradually drawn peoples' attention. This review summarizes recent studies on the functions and mechanisms of circRNAs in cisplatin resistance. We emphasize that circRNA can be used as a promising target gene to improve drug resistance and therapeutic efficacy.

Blockade of endoplasmic reticulum stress-induced cell death by Ureaplasma parvum vacuolating factor

Previously, we found that Ureaplasma parvum internalised into HeLa cells and cytosolic accumulation of galectin-3. U. parvum induced the host cellular membrane damage and survived there. Here, we conducted vesicular trafficking inhibitory screening in yeast to identify U. parvum vacuolating factor (UpVF). U. parvum triggered endoplasmic reticulum (ER) stress and upregulated the unfolded protein response-related factors, including BiP, P-eIF2 and IRE1 in the host cells, but it blocked the induction of the downstream apoptotic factors. MicroRNA library screening of U. parvum-infected cells and UpVF-transfected cells identified miR-211 and miR-214 as the negative regulators of the apoptotic cascade under ER stress. Transient expression of UpVF induced HeLa cell death with intracellular vacuolization; however, some stable UpVF transformant survived. U. parvum-infected cervical cell lines showed resistance to actinomycin D, and UpVF stable transformant cell lines exhibited resistance to X-ray irradiation, as well as cisplatin and paclitaxel. UpVF expressing cervical cancer xenografts in nude mice also acquired resistance to cisplatin and paclitaxel. A mycoplasma expression vector based on Mycoplasma mycoides, Syn-MBA (multiple banded antigen)-UpVF, reduced HeLa cell survival compared with that of Syn-MBA after 72 hr of infection. These findings together suggest novel mechanisms for Ureaplasma infection and the possible implications for cervical cancer malignancy. TAKE AWAYS: • Ureaplasmal novel virulence factor, UpVF, was identified. • UpVF triggered ER stress but suppressed apoptotic cascade via miR-211 and -214. • UpVF conferred resistance to anticancer treatments both in vivo and in vitro. • Dual expression of MBA and UpVF in JCVI-syn3B showed host cell damage.

Metallodrugs as Anticancer Chemotherapeutics and Diagnostic Agents: A Critical Patent Review (2010-2020)

BACKGROUND

The development of metallodrugs with potential applications in cancer treatment and diagnosis has been a hot topic since the approval and subsequent marketing of the anticancer drug cisplatin in 1978. Since then, thousands of metal-based derivatives have been reported and evaluated for their chemotherapeutic or tumor imaging properties, but only a very limited number gained clinical status. Nonetheless, research in the field has been increasing exponentially over the years, especially in a view to exploiting novel drug designing approaches and strategies aimed at improving pharmacological outcomes and, at the same time, reducing side-effects.

OBJECTIVE

This review article reports on the patents filed during the last decade and strictly focusing on the development of metal-based anticancer and diagnostic agents. The goal is to identify the latest trends and designing strategies in the field, which would represent a valuable starting point to researchers interested in the development of metallodrugs.

METHODS

The most relevant patents filed in the 2010-2020 timeframe have been retrieved from various databases using dedicated search engines (such as SciFinder, Google Patents, PatentPak, Espacenet, Global Dossier, PatentScope), sorted by type of metallodrug and screened to include those reporting a substantial amount of biological data.

RESULTS

The majority of patents here reviewed are concerned with metallodrugs (mostly platinum-based) showing interesting pharmacological properties but no specific tumor-targeting features. Nonetheless, some promising trends in the development of novel drug delivery strategies and/or metallodrugs with potential applications in targeted chemotherapy are envisaged.

CONCLUSION

In this review, the latest trends in the development of metallodrugs from recent patents are summarized and critically discussed. Such trends would be of interest not only to the scientific community but also to lay audiences aiming to broaden their knowledge of the field and industrial stakeholders potentially interested in the exploitation and commercialization of this class of pharmaceuticals.

Roles of circRNAs in cancer chemoresistance (Review)

Circular RNA (circRNA) is a type of endogenous, high‑stability, noncoding RNA. circRNAs exhibit various biological functions, and are involved in physiological and pathological processes occurring in various diseases, including cancers. They can not only act as microRNA and protein sponges, but also interact with proteins, translated peptides, and transcriptional and translational regulators, and compete with pre‑mRNA splicing. Chemotherapy is one of the most important types of cancer treatment. However, the resistance of cancer cells to chemotherapy is a leading reason for the failure of chemotherapy. It has been reported that circRNAs play important roles in cancer resistance via a number of mechanisms. The functions of the circRNAs provide insight into their roles in chemoresistance pathways. In addition, some circRNAs may serve as novel biomarkers for the diagnosis and prognosis of cancer resistance. Obtaining improved understanding of the molecular regulatory networks featuring circRNAs in tumors and searching for markers for the diagnosis and treatment of cancer resistance are leading issues in circRNA research. The present review introduced the functions of circRNAs, illustrated the mechanisms underlying drug resistance in cancer, described the contributions of circRNAs to this resistance and discussed the potential application of circRNAs in the treatment of drug‑resistant cancer. In particular, the review aimed to reveal the main mechanisms of circRNAs in cancer drug resistance, including mechanisms involving drug transport and metabolism, alterations of drug targets, DNA damage repair, downstream resistance mechanisms, adaptive responses and the tumor microenvironment. The findings may provide novel therapeutic targets for clinical treatment of cancer chemoresistance.

Does Bromelain-Cisplatin Combination Afford In-Vitro Synergistic Anticancer Effects on Human Prostatic Carcinoma Cell Line, PC3?

Background:

Bromelain enhances anticancer impacts to chemotherapeutic agents. The question as to whether bromelain does promote in-vitro cytotoxic and proapoptotic effects of cisplatin on human prostatic carcinoma PC3 cell line was investigated.

Materials and Methods:

PC3 (human prostatic carcinoma) cells were treated either single or in combination with bromelain and/or cisplatin. MTT, clonogenic assay, flow cytometry and real-time quantitative polymerase chain reaction were used to investigate cell viability, colony formation, proapoptotic potential and p53 gene expression, respectively.

Results:

Cisplatin (IC₁₀) combined with bromelain (IC₄₀) significantly affected PC3 cell viability, inhibited colony formation, as well increased p53 proapoptotic gene expression compared to cisplatin single treatment. Nevertheless, bromelain-cisplatin chemoherbal combination did not display any additive proapoptotic effect compared to single treatments.

Conclusion:

Bromelain-cisplatin chemoherbal combination demonstrated synergistic in-vitro anticancer effect on human prostatic carcinoma cell line, PC3, that drastically reduced required cisplatin dose.

COOH-Terminated Silicon Quantum Dots as a Highly Efficient Drug Nanocarrier for Targeted Tumor Cell Imaging

Fluorescent silicon quantum dots (SiQDs) characterized by exceptional photostability and colloidal robustness as well as beneficial biocompatibility are fast becoming new pharmaceutical nanocarriers. With a view to efficiently loading cisplatin (CDDP) onto SiQDs, carboxylate group (COOH) terminated SiQDs were imperative because of chelate formation with CDDP. In this work, we employed a facial microwave irradiation route for rapidly synthesizing high-quality COOH-SiQDs through the use of 3-aminopropyl trimethoxy silane (APTMS) molecules to fulfil the role of silicon precursor and maleic acid (MA) as the agent for facilitating reduction. The SiQDs showed blue fluorescence with an associated photoluminescence quantum yield (PLQY) of 40.2%, the size of which was small at 3.2 ±0.6 nm, and long-lasting stability (an extensive range in pH (4-12) and concentrations of electrolytes reaching 3 Molarity of a solution of sodium chloride). As nanocarriers, carboxylic acids chelation generated a high loading of CDDP onto SiQDs (drug loading capacity, DLC up to 32.2% at pH = 9) and a drug release of CDDP up to 57.6% at pH = 5. Furthermore, the MTT assays demonstrated the non or low cytotoxicity of SiQDs and the role of the controlled release of SiQD-CDDP Finally, the prepared SiQD-CDDP were used for cell imaging, and further targeted labeling of some tumors after folic acid (FA) conjugation. These characteristics allow for the deployment of SiQDs as a highly efficient nanocarrier that facilitate the delivery of clinical drugs for the future.

Investigation of differentially expressed gene profile for cisplatin-treated lung cancer patients

The purpose of the study was to establish a comprehensive differential gene profile for lung cancer patients treated with cisplatin compared with control patients without any chemotherapy drug treatment. The RNA sequencing data and miRNA sequencing data of 108 lung cancer patients treated with cisplatin only and 232 lung cancer patients treated without any chemotherapeutic drugs, were analyzed using differential expression, protein-protein interaction, and immune cell infiltration ratio analysis. Compared with control patients, the cisplatin-treated patients demonstrated 336 differentially expressed genes, which included 48 upregulated genes and 288 downregulated genes. Meanwhile, 12 differentially expressed miRNAs (DEMs), including 7 upregulated miRNAs and 5 downregulated miRNAs showed a differentially expressed pattern. With further instigation, five miRNAs (hsa-miR-548ah, hsa-miR-466, hsa-miR-552, hsa-miR-371a, and hsa-miR-4445) were suggested to be the key targets in the cisplatin-treated patients. At the same time, we also found a significant correlation between the cisplatin treatment and six immune checkpoints including programmed cell death ligand. This study helped us better understand the potential targets and underline molecular mechanisms for cisplatin treatment and provided references to eliminate existing side effects in the future.

A newly established monoclonal antibody against ERCC1 detects major isoforms of ERCC1 in gastric cancer

Identifying patients resistant to cisplatin treatment is expected to improve cisplatin-based chemotherapy for various types of cancers. Excision repair cross-complementing group 1 (ERCC1) is involved in several repair processes of cisplatin-induced DNA crosslinks. ERCC1 overexpression is reported as a candidate prognostic factor and considered to cause cisplatin resistance in major solid cancers. However, anti-ERCC1 antibodies capable of evaluating expression levels of ERCC1 in clinical specimens were not fully optimized. A mouse monoclonal antibody against human ERCC1 was generated in this study. The developed antibody 9D11 specifically detected isoforms of 201, 202, 203 but not 204, which lacks the exon 3 coding region. To evaluate the diagnostic usefulness of this antibody, we have focused on gastric cancer because it is one of the major cancers in Japan. When ERCC1 expression was analyzed in seventeen kinds of human gastric cancer cell lines, all the cell lines were found to express either 201, 202, and/or 203 as major isoforms of ERCC1, but not 204 by Western blotting analysis. Immunohistochemical staining showed that ERCC1 protein was exclusively detected in nuclei of the cells and a moderate level of constant positivity was observed in nuclei of vascular endothelial cells. It showed a clear staining pattern in clinical specimens of gastric cancers. Antibody 9D11 may thus be useful for estimating expression levels of ERCC1 in clinical specimens.

Synergistic Anticancer Effects of Cisplatin Combined with Combretastatin A4 Phosphate on Human Osteosarcoma-Xenografted Mice

This study aimed to investigate the effectiveness of anticancer therapy combining a cytotoxic chemotherapeutic agent, cisplatin (DDP), and a vascular disruptive drug, combretastatin A4 phosphate (CA4P), in osteosarcoma. First, a human osteosarcoma-xenografted mice model was established. Second, the transplanted tumor models were treated with DDP and CA4P in combination or as monotherapy. Third, the therapeutic effects and the mechanism of the drug combination in the inhibition of transplanted tumors was studied. Finally, the toxic effects of the drugs were observed and recorded. The results showed that DDP combined with CA4P significantly inhibited the growth and lung metastasis of transplanted tumors compared with the monotherapy drug group and vehicle control group. Histopathological analysis revealed that apoptotic and necrotic cell death significantly increased in the combination group, and combined treatment significantly inhibited the proliferation of osteosarcoma cells compared with either agent alone or the vehicle control. Additionally, no obvious toxic effects were observed in the combination group. These results indicate that the combined effects of DDP and CA4P on the progression of human osteosarcoma in vivo were superior to that of either agent alone. DDP combined with CA4P exerted synergistic effects at lower concentrations and promoted apoptosis and necrosis, as well as inhibited proliferation of osteosarcoma cells, but it did not increase the systemic toxic effects of chemotherapy. Our findings highlight CA4P as an effective anticancer agent candidate for combination with DDP in clinical applications to treat osteosarcoma.

Development of a multi-target anticancer Sn(ii) pyridine-2-carboxaldehyde thiosemicarbazone complex

In this study, we proposed to design effective multi-target anticancer agents based on the chelation of nontoxic metals with ligands that possess anticancer activity. In total, five Sn(ii) pyridine-2-carboxaldehyde thiosemicarbazone complexes are synthesized and their activities are tested. Among these complexes, C5 is found to show the highest cytotoxicity on investigating their structure-activity relationships. In addition, C5 not only exhibits an effective inhibitory effect against tumor growth in vivo, but also suppresses angiogenesis and restricts the metastasis of cancer cells in vitro. Multiple mechanisms underlie the antitumor effect of C5, and they include acting against DNA, inducing apoptosis, and inhibiting the activities of anti-apoptotic Bcl-xL protein, metalloproteinase MMP2 and topoisomerase II.

Nanoparticles of cisplatin augment drug accumulations and inhibit multidrug resistance transporters in human glioblastoma cells

Background

Cisplatin (CSP) is a potent anticancer drug widely used in treating glioblastoma multiforme (GBM). However, CSP's clinical efficacy in GBM contrasted with low therapeutic ratio, toxicity, and multidrug resistance (MDR). Therefore, we have developed a system for the active targeting of cisplatin in GBM via cisplatin loaded polymeric nanoplatforms (CSP-NPs).

Methods

CSP-NPs were prepared by modified double emulsion and nanoprecipitation techniques. The physiochemical characterizations of CSP-NPs were performed using zeta sizer, scanning electron microscopy (SEM), drug release kinetics, and drug content analysis. Cytotoxicity, induction of apoptosis, and cell cycle-specific activity of CSP-NPs in human GBM cell lines were evaluated by MTT assay, fluorescent microscopy, and flow cytometry. Intracellular drug uptake was gauged by fluorescent imaging and flow cytometry. The potential of CSP-NPs to inhibit MDR transporters were assessed by flow cytometry-based drug efflux assays.

Results

CSP-NPs have smooth surface properties with discrete particle size with required zeta potential, polydispersity index, drug entrapment efficiency, and drug content. CSP-NPs has demonstrated an ‘initial burst effect’ followed by sustained drug release properties. CSP-NPs imparted dose and time-dependent cytotoxicity and triggered apoptosis in human GBM cells. Interestingly, CSP-NPs significantly increased uptake, internalization, and accumulations of anticancer drugs. Moreover, CSP-NPs significantly reversed the MDR transporters (ABCB1 and ABCG2) in human GBM cells.

Conclusion

The nanoparticulate system of cisplatin seems to has a promising potential for active targeting of cisplatin as an effective and specific therapeutic for human GBM, thus eliminating current chemotherapy's limitations.

Targeting MDSC for Immune-Checkpoint Blockade in Cancer Immunotherapy: Current Progress and New Prospects

Immune-checkpoint blockade (ICB) demonstrated inspiring effect and great promise in anti-cancer therapy. However, many obstacles, such as drug resistance and difficulty in patient selection, limited the efficacy of ICB therapy and awaited to be overcome. By timely identification and intervention of the key immune-suppressive promotors in the tumor microenvironment (TME), we may better understand the mechanisms of cancer immune-escape and use novel strategies to enhance the therapeutic effect of ICB. Myeloid-derived suppressor cell (MDSC) is recognized as a major immune suppressor in the TME. In this review, we summarized the roles MDSC played in the cancer context, focusing on its negative biologic functions in ICB therapy, discussed the strategies targeted on MDSC to optimize the diagnosis and therapy process of ICB and improve the efficacy of ICB therapy against malignancies.

Mutual Prodrugs of 5-Fluorouracil: From a Classic Chemotherapeutic Agent to Novel Potential Anticancer Drugs

The development of potent antitumor agents with a low toxicological profile against healthy cells is still one of the greatest challenges facing medicinal chemistry. In this context, the “mutual prodrug” approach has emerged as a potential tool to overcome undesirable physicochemical features and mitigate the side effects of approved drugs. Among broad‐spectrum chemotherapeutics available for clinical use today, 5‐fluorouracil (5‐FU) is one of the most representative, also included in the World Health Organization model list of essential medicines. Unfortunately, severe side effects and drug resistance phenomena are still the primary limits and drawbacks in its clinical use. This review describes the progress made over the last ten years in developing 5‐FU‐based mutual prodrugs to improve the therapeutic profile and achieve targeted delivery to cancer tissues.

Redox-sensitive TRP channels: a promising pharmacological target in chemotherapy-induced peripheral neuropathy

INTRODUCTION

Chemotherapy-induced peripheral neuropathy (CIPN) and its related pain is a major side effect of certain chemotherapeutic agents used in cancer treatment. Available analgesics are mostly symptomatic, and on prolonged treatment, patients become refractive to them. Hence, the development of improved therapeutics that act on novel therapeutic targets is necessary. Potential targets include the redox-sensitive TRP channels [e.g. TRPA1, TRPC5, TRPC6, TRPM2, TRPM8, TRPV1, TRPV2, and TRPV4] which are activated under oxidative stress associated with CIPN.

AREAS COVERED

We have examined numerous neuropathy-inducing cancer chemotherapeutics and their pathophysiological mechanisms. Oxidative stress and its downstream targets, the redox-sensitive TRP channels, together with their potential pharmacological modulators, are discussed. Finally, we reflect upon the barriers to getting new therapeutic approaches into the clinic. The literature search was conducted in PubMed upto and including April 2021.

EXPERT OPINION

Redox-sensitive TRP channels are a promising target in CIPN. Pharmacological modulators of these channels have reduced pain in preclinical models and in clinical studies. Clinical scrutiny suggests that TRPA1, TRPM8, and TRPV1 are the most promising targets because of their pain-relieving potential. In addition to the analgesic effect, TRPV1 agonist-Capsaicin possesses a disease-modifying effect in CIPN through its restorative property in damaged sensory nerves.

The Effect of Shenyi Capsule on Non-Small-Cell Lung Cancer Combined with Chemotherapy from the Yin-Yang Perspective

As an example of Shenyi capsule on non-small-cell lung cancer combined with chemotherapy, this review discusses the synergistic effect and mechanism of natural drugs in oncotherapy from the yin-yang perspective in ancient Chinese philosophy, so as to reflect the therapeutic principle of natural drugs for tumor more comprehensively. The major focuses of this review are on the philosophical thinking of yin-yang as a tool which can not only explain the effect of Shenyi capsule in NSCLC combined with chemotherapy but also explore the mechanism of Shenyi capsule at the cellular and molecular level. Learning from the "yin-yang" thinking of ancient Chinese philosophy will bring more enlightenment to the research and development of traditional Chinese drugs in the future.

Square-Planar vs. Trigonal Bipyramidal Geometry in Pt(II) Complexes Containing Triazole-Based Glucose Ligands as Potential Anticancer Agents

This article describes the synthesis, characterization, and biological activity of novel square-planar cationic platinum(II) complexes containing glucoconjugated triazole ligands and a comparison with the results obtained from the corresponding five-coordinate complexes bearing the same triazole ligands. Stability in solution, reactivity with DNA and small molecules of the new compounds were evaluated by NMR, fluorescence, and UV–vis absorption spectroscopy, together with their cytotoxic action against pairs of immortalized and tumorigenic cell lines. The results show that the square-planar species exhibit greater stability than the corresponding five-coordinate ones. Furthermore, although the square-planar complexes are less cytotoxic than the latter ones, they exhibit a certain selectivity. These results simultaneously demonstrate that overall stability is a fundamental prerequisite for preserving the performance of the agents and that coordinative saturation constitutes a point in favor of their biological action.

ZIPK activates the IL-6/STAT3 signaling pathway and promotes cisplatin resistance in gastric cancer cells

Gastric cancer is one of the most common malignant cancers globally. Chemotherapy resistance remains a major obstacle in the treatment of gastric cancer, and the molecular mechanisms underlying drug resistance are still not well understood. We previously reported that Zipper interacting protein kinase (ZIPK), also known as death‐associated protein kinase3, exerts an oncogenic effect on gastric cancer via activation of Akt/NF‐κB signaling and promotion of stemness. Here, we explored the roles of ZIPK in cisplatin resistance. We report that ZIPK enhances cell proliferation and invasion and reduces the antitumor activity of cisplatin in gastric cancer. In addition, our western blot data suggest that ZIPK activated the IL‐6/STAT3 signaling pathway. Furthermore, ZIPK increased the expression of IL‐6 and multidrug‐resistance genes. Using the STAT3 inhibitor stattic to block the IL‐6/STAT3 signaling pathway strongly increased the sensitivity of ZIPK‐expressed cells to cisplatin. In conclusion, ZIPK may play a role in cisplatin resistance through activation of the IL‐6/ STAT3 signaling pathway. Inhibition of STAT3 in gastric cancer overexpressing ZIPK might have potential to improve the efficacy of cisplatin.

Dual inhibition of FGFR4 and BCL-xL inhibits multi-resistant ovarian cancer with BCL2L1 gain

Aim: Overexpression of BCL2L1 (BCL-xL) was associated with platinum resistance in ovarian cancer (OvCa). However, role of copy number (CN) gain of BCL2L1 in OvCa remains elusive.

Methods: In silico analyses of multiple public datasets were perform. Validation was carried out in our tissue microarray (TMA) of OvCa cases. In vitro and in vivo assays was performed to explore potential targeted compound against BCL2L1-gained OvCa.

Results: BCL2L1 was gained in ~60% of OvCa. BCL2L1 was differentially expressed between healthy and cancerous ovarian cases. BCL2L1 gain was not prognostic either in overall or in progression-free survival but higher BCL2L1 expression was associated with worsened survival, indicating biological distinction between CN gain and overexpression of the gene. BCL2L1 gain was associated with multi-resistance to various drug with no significant sensitivity to any single agent. Only CRISPR-mediated BCL2L1 knockout, but not shRNA could be inhibitive. Combined genetic silencing of FGFR4/NCAM and BCL2L1 with shRNA induced potent inhibition of BCL2L1-gained OvCa with durable effect. Combined inhibition of FGFR/BCL-xL was required for inhibiting BCL2L1-gained OvCa in vitro and in vivo. Only dual inhibition of FGFR/BCL-xL without platinum was tolerable in vivo.

Conclusion: Gain of BCL2L1 is associated with resistance to multiple anti-cancer agents in OvCa. Dual inhibition of FGFR4 and BCL-xL showed potent effect and tolerable toxicity, holding promise to further translation.

Recent Progresses in Conjugation with Bioactive Ligands to Improve the Anticancer Activity of Platinum Compounds

Platinum (Pt) drugs, including cisplatin, are widely used for the treatment of solid tumors. Despite the clinical success, side effects and occurrence of resistance represent major limitations to the use of clinically available Pt drugs. To overcome these problems, a variety of derivatives have been designed and synthetized. Here, we summarize the recent progress in the development of Pt(II) and Pt(IV) complexes with bioactive ligands. The development of Pt(II) and Pt(IV) complexes with targeting molecules, clinically available agents, and other bioactive molecules is an active field of research. Even if none of the reported Pt derivatives has been yet approved for clinical use, many of these compounds exhibit promising anticancer activities with an improved pharmacological profile. Thus, planning hybrid compounds can be considered as a promising approach to improve the available Pt-based anticancer agents and to obtain new molecular tools to deepen the knowledge of cancer progression and drug resistance mechanisms.

Curcumin-cisplatin chemotherapy: A novel strategy in promoting chemotherapy efficacy and reducing side effects

The efficacy of chemotherapy in cancer therapy is limited due to resistance, treatment selectivity, and severe adverse effects. Immunotherapy, chemotherapy, targeted therapy, radiation, and surgery are the most common therapeutic strategies for treatment, with chemotherapy being the most successful. Nonetheless, these treatments exhibit poor effectiveness due to toxicity and resistance. Therefore, combination therapies of natural products may be used as an effective and novel strategy to overcome such barriers. Cisplatin is a platinum-based chemotherapy agent, and when administered alone, it can lead to severe adverse effects and resistance mechanism resulting in therapeutic failure. Curcumin is a polyphenolic compound extracted from turmeric (Curcuma longa) exhibiting anticancer potential with minimal adverse effects. The combination therapy of curcumin and cisplatin is a novel strategy to mitigate/attenuate cisplatin-related adverse effects and improve the barrier of resistance reducing unwanted effects. However, there are uncertainties on the efficacy of curcumin, and more in depth and high-quality studies are needed. This review aims to explain the adverse effects related to individual cisplatin delivery, the positive outcome of individual curcumin delivery, and the combination therapy of curcumin and cisplatin from nano platform as a novel strategy for cancer therapy.

Supramolecular Polymerization-Induced Nanoassemblies for Self-Augmented Cascade Chemotherapy and Chemodynamic Therapy of Tumor

The clinical application of chemodynamic therapy is impeded by the insufficient intracellular H2 O2 level in tumor tissues. Herein, we developed a supramolecular nanoparticle via a simple one-step supramolecular polymerization-induced self-assembly process using platinum (IV) complex-modified β-cyclodextrin-ferrocene conjugates as supramolecular monomers. The supramolecular nanoparticles could dissociate rapidly upon exposure to endogenous H2 O2 in the tumor and release hydroxyl radicals as well as platinum (IV) prodrugs in situ, which is reduced into cisplatin to significantly promote the generation of H2 O2 in the tumor tissue. Thus, the supramolecular nanomedicine overcomes the limitation of conventional chemodynamic therapy via the self-augmented cascade radical generation and drug release. In addition, dissociated supramolecular nanoparticles could be readily excreted from the body via renal clearance to effectively avoid systemic toxicity and ensure long term biocompatibility of the nanomedicine. This work may provide new insights on the design and development of novel supramolecular nanoassemblies for cascade chemo/chemodynamic therapy.

Mitochondria-acting carrier-free nanoplatform self-assembled by α-tocopheryl succinate carrying cisplatin for combinational tumor therapy

Unsatisfactory drug loading capability, potential toxicity of the inert carrier and the limited therapeutic effect of a single chemotherapy drug are all vital inhibitory factors of carrier-assisted drug delivery systems for chemotherapy. To address the above obstacles, a series of carrier-free nanoplatforms self-assembled by dual-drug conjugates was constructed to reinforce chemotherapy against tumors by simultaneously disrupting intratumoral DNA activity and inhibiting mitochondria function. In this nanoplatform, the mitochondria-targeting small-molecular drug, α-tocopheryl succinate (TOS), firstly self-assembled into nanoparticles, which then were used as the carrier to conjugate cisplatin (CDDP). Systematic characterization results showed that this nanoplatform exhibited suitable particle size and a negative surface charge with good stability in physicochemical environments, as well as pH-sensitive drug release and efficient cellular uptake. Due to the combined effects of reactive oxygen species (ROS) generation by TOS and DNA damage by CDDP, the developed nanoplatform could induce mitochondrial dysfunction and elevated cell apoptosis, resulting in highly efficient anti-tumor outcomes in vitro. Collectively, the combined design principles adopted for carrier-free nanodrugs construction in this study aimed at targeting different intracellular organelles for facilitating ROS production and DNA disruption can be extended to other carrier-free nanodrugs-dependent therapeutic systems.

miR-526b-3p inhibits lung cancer cisplatin-resistance and metastasis by inhibiting STAT3-promoted PD-L1

Chemotherapy remains the primary treatment of advanced solid cancer, including lung cancer. However, as first-line treatment, cisplatin-based therapy is restricted by the frequent development of drug resistance. Increasing data showed that the programmed cell death protein ligand 1 (PD-L1) plays a vital role in regulating cisplatin resistance. However, the underlying mechanisms are not fully understood. We found that miR-526b-3p expression declined while PD-L1 was elevated in cisplatin-resistant lung cancer compared to that in cisplatin-sensitive lung cancer by analyzing clinical samples. Significantly, miR-526b-3p was associated with response to cisplatin negatively. We further demonstrated that miR-526b-3p reversed cisplatin resistance, suppressed metastasis, and activated CD8+ T cells in a STAT3/PD-L1-dependent manner. Thus, our findings extended the knowledge of PD-L1-mediated cisplatin resistance of lung cancer. In addition, the introduction of miR-526b-3p provided a new clue to improve the anti-tumor effects of the combination of immunotherapy and chemotherapy.

Recent developments of metal-based compounds against fungal pathogens

This review provides insight into the rapidly expanding field of metal-based antifungal agents. In recent decades, the antibacterial resistance crisis has caused reflection on many aspects of public health where weaknesses in our medicinal arsenal may potentially be present - including in the treatment of fungal infections, particularly in the immunocompromised and those with underlying health conditions where mortality rates can exceed 50%. Combination of organic moieties with known antifungal properties and metal ions can lead to increased bioavailability, uptake and efficacy. Development of such organometallic drugs may alleviate pressure on existing antifungal medications. Prodigious antimicrobial moieties such as azoles, Schiff bases, thiosemicarbazones and others reported herein lend themselves easily to the coordination of a host of metal ions, which can vastly improve the biocidal activity of the parent ligand, thereby extending the library of antifungal drugs available to medical professionals for treatment of an increasing incidence of fungal infections. Overall, this review shows the impressive but somewhat unexploited potential of metal-based compounds to treat fungal infections.

Fabrication, optimisation and evaluation of cisplatin-loaded nanostructured carriers for improved urothelium permeability for intravesical administration

AIM

To design microemulsions as carriers to improve cisplatin permeation capability for intravesical administration.

METHOD

The response surface methodology with factorial design was used to investigate and optimise the influence of the compositions e.g. capryol 90 and 5-pentanediol/transcutol mixture on the permeation accumulation amount and tissue deposition amount of cisplatin-loaded microemulsions. The in vitro permeation study and in vivo intravesical test were conducted to prove the effect of microemulsions.

RESULTS

The droplet size and the viscosity of all drug-loaded formulations ranged 235.8-309.3 nm and 550.8-861.7 cps, respectively. The permeation accumulation amounts significantly increased about 26-fold, by used microemulsion as carriers. In vivo study, the cisplatin deposition amount in bladder tissue significantly increased 4.1-fold (p < 0.05) and the penetration depth increased from 60 μm up 120 μm. The nanocarrier showed considerable thermodynamic stability.

CONCLUSION

The designed nanocarrier was considered to be a promising delivery system for cisplatin intravesical administration.

Ruthenium Complexes as Promising Candidates against Lung Cancer

Lung cancer is one of the most common malignancies with the highest mortality rate and the second-highest incidence rate after breast cancer, posing a serious threat to human health. The accidental discovery of the antitumor properties of cisplatin in the early 1960s aroused a growing interest in metal-based compounds for cancer treatment. However, the clinical application of cisplatin is limited by serious side effects and drug resistance. Therefore, other transition metal complexes have been developed for the treatment of different malignant cancers. Among them, Ru(II/III)-based complexes have emerged as promising anticancer drug candidates due to their potential anticancer properties and selective cytotoxic activity. In this review, we summarized the latest developments of Ru(II/III) complexes against lung cancer, focusing mainly on the mechanisms of their biological activities, including induction of apoptosis, necroptosis, autophagy, cell cycle arrest, inhibition of cell proliferation, and invasion and metastasis of lung cancer cells.

Quinoline-based Compounds with Potential Activity against Drugresistant Cancers

Drug resistance is the major cause of the failure of cancer chemotherapy, so one of the most important features in developing effective cancer therapeutic strategies is to overcome drug resistance. Quinoline moiety has become one of the most privileged structural motifs in anticancer agent discovery since its derivatives possess potent activity against various cancers including drug-resistant cancers. Several quinoline-based compounds which are represented by Anlotinib, Bosutinib, Lenvatinib, and Neratinib have already been applied in clinical practice to fight against cancers, so quinoline-based compounds are potential anticancer agents. The present short review article provides an overview of the recent advances of quinoline-based compounds with potential activity against drug-resistant cancers. The structure-activity relationship and mechanisms of action are also discussed.

MicroRNA-25-3p promotes cisplatin resistance in Non-small-cell lung carcinoma (NSCLC) through adjusting PTEN/PI3K/AKT route

MicroRNAs exert crucial effects in the drug resistance. The purpose of this research was to investigate the miR-25-3p effects on DDP resistance in NSCLC. We used RT-qPCR to evaluate the expression of miR-25-3p. Cell growth was determined using MTS assay. Cellular bio-activity was analyzed via Colony formation, Annexin V/PI, and Transwell assay. Luciferase reporter assay was used to determine miR-25-3p and PTEN binding. Western blot was used to determine PTEN, PI3K, p-AKT/AKT expression. In-vivo study was used to determine the effects of miR-25-3p on the tumor growth. Expression of miR-25-3p is increased in NSCLC cisplatin resistant A549 and H1299 cells. Furthermore, miR-25-3p mimic enhanced drug resistance, and accelerated cell invasion and metastasis. Moreover, miR-25-3p mimic resulted in the activation of PTEN/PI3K/AKT pathway. However, miR-25-3p inhibitors exhibited the opposite trend. We further identified PTEN as a potential target of miR-25-3p. PTEN knockout promoted cisplatin resistance, while PTEN mimic displayed opposite effects. Interestingly, miR-25-3p further boosted cisplatin resistance cells in vivo, and miR-25-3p inhibitors reduced the in-vivo tumor volume. MiR-25-3p/PTEN/PI3K/AKT axis might accelerate DDP tolerance in NSCLC, which may serve as a potential target for chemotherapy resistance in NSCLC.

DHA exhibits synergistic therapeutic efficacy with cisplatin to induce ferroptosis in pancreatic ductal adenocarcinoma via modulation of iron metabolism

Pancreatic ductal adenocarcinoma (PDAC) is an extremely lethal cancer with limited treatment options. Cisplatin (DDP) is used as a mainstay of chemotherapeutic agents in combination with other drugs or radiotherapy for PDAC therapy. However, DDP exhibits severe side-effects that can lead to discontinuation of therapy, and the acquired drug resistance of tumor cells presents serious clinical obstacles. Therefore, it is imperative to develop a more effective and less toxic therapeutic strategy. We and others have previously discovered that dihydroartemisinin (DHA) represents a safe and promising therapeutic agent to preferentially induce cancer cell ferroptosis. In the present study, we find that DHA could intensively strengthen the cytotoxicity of DDP and significantly reduce its effective concentrations both in vitro and in vivo. Combination of DHA and DDP synergistically inhibits the proliferation and induces DNA damage of PDAC cells. Mechanically, the combinative treatment impairs mitochondrial homeostasis, characterized by destroyed mitochondrial morphology, decreased respiratory capacity, reduced ATP production, and accumulated mitochondria-derived ROS. Further studies show that ferroptosis contributes to the cytotoxic effects in PDAC cells under the challenge of DHA and DDP, together with catastrophic accumulation of free iron and unrestricted lipid peroxidation. Moreover, pharmacologic depleting of the free iron reservoir or reconstituted expression of FTH contributes to the tolerance of DHA/DDP-induced ferroptosis, while iron addition accelerates the ferroptotic cell death. In summary, these results provide experimental evidence that DHA acts synergistically with DDP and renders PDAC cells vulnerable to ferroptosis, which may act as a promising therapeutic strategy.

Ruthenium(II) and Platinum(II) Complexes with Biologically Active Aminoflavone Ligands Exhibit In Vitro Anticancer Activity

Continuing our studies on the mechanisms underlying the cytotoxicity of potential drugs, we have described several aspects of the in vitro anticancer activity of ruthenium(II) and platinum(II) complexes with bioactive, synthetic aminoflavone ligands. We examined the mechanism of proapoptotic activity of cis-dichlorobis(3-imino-2-methoxyflavanone)ruthenium(II), cis-dichlorobis(3-imino-2-ethoxyflavanone)ruthenium(II), and trans-dichlorobis(3-aminoflavone)platinum(II). Cisplatin was used as a reference compound. The cytotoxicity was investigated by MTT assay. The mechanism of proapoptotic activity of the tested compounds was investigated by evaluation of caspase-8 activity, cytometric analysis of annexin-V positive cells, and mitochondrial potential loss measurement. The results showed that ruthenium compounds break partially or completely the cisplatin resistance by activating the caspase 8-dependent apoptosis pathway and loss of mitochondrial membrane potential. Platinum compounds also have a cytostatic effect, but their action requires more exposure time. Potential mechanisms underlying drug resistance in the two pairs of cancer cell lines were investigated: total glutathione content, P-glycoprotein activity, and differences in the activity of DNA repair induced by nucleotide excision. Results showed that cisplatin-resistant cells have elevated glutathione levels relative to sensitive cells. Moreover, they indicated the mechanisms enabling cells to avoid apoptosis caused by DNA damage. Pg-P activity has no effect on the development of cisplatin resistance in the cell lines described.

Protective Effect of Polysaccharides Extracted from Cudrania tricuspidata Fruit against Cisplatin-Induced Cytotoxicity in Macrophages and a Mouse Model

Although cisplatin is one of most effective chemotherapeutic drugs that is widely used to treat various types of cancer, it can cause undesirable damage in immune cells and normal tissue because of its strong cytotoxicity and non-selectivity. This study was conducted to investigate the cytoprotective effects of Cudrania tricuspidata fruit-derived polysaccharides (CTPS) against cisplatin-induced cytotoxicity in macrophages, lung cancer cell lines, and a mouse model, and to explore the possibility of application of CTPS as a supplement for anticancer therapy. Both cisplatin alone and cisplatin with CTPS induced a significant cytotoxicity in A549 and H460 lung cancer cells, whereas cytotoxicity was suppressed by CTPS in cisplatin-treated RAW264.7 cells. CTPS significantly attenuated the apoptotic and necrotic population, as well as cell penetration in cisplatin-treated RAW264.7 cells, which ultimately inhibited the upregulation of Bcl-2-associated X protein (Bax), cytosolic cytochrome c, poly (adenosine diphosphateribose) polymerase (PARP) cleavage, and caspases-3, -8, and -9, and the downregulation of B cell lymphoma-2 (Bcl-2). The CTPS-induced cytoprotective action was mediated with a reduction in reactive oxygen species production and mitochondrial transmembrane potential loss in cisplatin-treated RAW264.7 cells. In agreement with the results obtained above, CTPS induced the attenuation of cell damage in cisplatin-treated bone marrow-derived macrophages (primary cells). In in vivo studies, CTPS significantly inhibited metastatic colonies and bodyweight loss as well as immunotoxicity in splenic T cells compared to the cisplatin-treated group in lung metastasis-induced mice. Furthermore, CTPS decreased the level of CRE and BUN in serum. In summation, these results suggest that CTPS-induced cytoprotective action may play a role in alleviating the side effects induced by chemotherapeutic drugs.

Suppressing ERK Pathway Impairs Glycochenodeoxycholate-Mediated Survival and Drug-Resistance in Hepatocellular Carcinoma Cells

Glycochenodeoxycholate (GCDA), a toxic component in bile salts, is involved in carcinogenesis of gastrointestinal tumors. The objective of this research was to study the function of ERK1/2 in the GCDA-mediated survival and drug-resistance in hepatocellular carcinoma cells (HCCs). Firstly, extracellular signal-regulated kinase 1/2 (ERK1/2) was detected extensively expressed in liver cancer cells, and silencing ERK1/2 by RNA interference could suppress GCDA-stimulated survival and promote apoptosis. Furthermore, phosphorylation of endogenous ERK1/2 could be potently stimulated by GCDA in combination with enhanced chemoresistance in QGY-7703 hepatocellular carcinoma cells. The GCDA-mediated proliferation and chemoresistance could be impaired by PD98059, which acted as an inhibitor to block the phosphorylation of ERK1/2. Mechanistically, PD98059 was able to potently suppress GCDA-stimulated nuclear aggregation of ERK1/2 and p-ERK1/2, upregulate pro-survival protein Mcl-1 and downregulate pro-apoptotic protein Bim. The results of this study indicated that disruption of ERK1/2 by blocking phosphorylation or nuclear translocation may put forward new methods for solving the problem of GCDA-related proliferation and drug-resistance in liver cancer treatment.

Programmed cell death, redox imbalance, and cancer therapeutics

Cancer cells are disordered by nature and thus featured by higher internal redox level than healthy cells. Redox imbalance could trigger programmed cell death if exceeded a certain threshold, rendering therapeutic strategies relying on redox control a possible cancer management solution. Yet, various programmed cell death events have been consecutively discovered, complicating our understandings on their associations with redox imbalance and clinical implications especially therapeutic design. Thus, it is imperative to understand differences and similarities among programmed cell death events regarding their associations with redox imbalance for improved control over these events in malignant cells as well as appropriate design on therapeutic approaches relying on redox control. This review addresses these issues and concludes by bringing affront cold atmospheric plasma as an emerging redox controller with translational potential in clinics.

Early phago-/endosomal escape of platinum drugs via ROS-responsive micelles for dual cancer chemo/immunotherapy

Recent studies have indicated that cancer treatment based on immunotherapy alone is not viable. Combined treatment with other strategies is required to achieve the expected therapeutic effect. Reactive oxygen species (ROS) play an important role in regulating cancer cells and the tumor microenvironment, even in immune cells. However, rigorous regulation of the ROS level within the entire tumor tissue is difficult, limiting the application of ROS in cancer therapy. Therefore, we design an early phago-/endosome-escaping micelle that can release platinum-based drugs into the cytoplasm of macrophages and cancer cells, thereby enhancing the ROS levels of the entire tumor tissue; inducing apoptosis of cancer cells, down-regulation of CD47 expression of cancer cells, polarization of M1 macrophages, and phagocytosis of cancer cells by M1 macrophages; and achieving the dual effect of chemotherapy and macrophage-mediated immunotherapy.

Detection and Characterization of Single Cisplatin Adducts on DNA by Nanopore Sequencing

Detection and characterization of an individual cisplatin adduct on a single DNA molecule is a demanding task. We explore the characteristic features of cisplatin adducts in the nanopore sequencing signal in aspects of dwell time, genome anchored current trace, and basecalling accuracy. The offset between the motor protein and the nanopore constriction region is revealed by dwell time analysis to be about 14 bases in the nanopore device as we examined. Characteristic distortions due to cisplatin adducts are illustrated in genome anchored current trace analysis, constituting the fingerprint for identification of cisplatin adduct. The sharp increase in odds ratio at the location of adducting sites provides additional feature in the detection of the adduct. By these combined methods, single cisplatin adducts can be detected with high fidelity on a single read of the DNA sequence. The study demonstrates an effective method in the detection and characterization of single cisplatin adducts on DNA at the single-molecule level and with single nucleotide spatial resolution.

Protective Effect of Aloe vera Gel against Cisplatin-Induced Testicular Damage, Sperm Alteration and Oxidative stress in Rats

BACKGROUND

Cisplatin (CIS) is an effective antineoplas tic drug that is used to treat various types of cancers. However, it causes side effects on the male reproductive sys tem. The present s tudy aimed to inves tigate the possible protective effects of Aloe vera (AL) gel (known as an antioxidant plant) on CIS-induced changes in rat sperm parameters, tes ticular s tructure, and oxidative s tress markers.

MATERIALS AND METHODS

In this experimental study, forty-eight adult male rats were divided into 6 groups including: control, CIS, AL, metformin (MET), CIS+AL, and CIS+MET. CIS was used intraperitoneally at a dose of 5 mg/kg on days 7, 14, 21, and 28 of the experiment. AL gel (400 mg/kg per day) and MET (200 mg/kg per day) were administered orally for 35 days (started one week before the beginning of the experiment). Testes weight and dimensions, and morphometrical and histological alterations, activities of antioxidant enzymes including superoxide dismutase (SOD) and glutathione peroxidase (GPx), serum testosterone concentration, lipid peroxidation level, and sperm parameters were examined.

RESULTS

CIS caused a significant decrease (P<0.05) in relative weight and dimension of the testis, germinal epithelium thickness and diameter of seminiferoustubules, the numbers of testicular cells, and spermatogenesis indexes. The malondialdehyde (MDA) levels increased and antioxidant enzymes activities decreased in the CIS group compared to the control group (P<0.05). Additionally, sperm parameters (concentration, viability, motility, and normal morphology), and testosterone levels reduced significantly in CIS-treated rats (P<0.05). Also, CIS induced histopathological damages including disorganization, desquamation, atrophy, and vacuolation in the testis. However, administration of AL gel to CIS-treated rats attenuated the CIS-induced alterations, mitigated testicular oxidative stress and increased testosterone concentration.

CONCLUSION

The results suggest that AL as a potential antioxidant plant and due to free radicals scavenging activities, has a protective effect against CIS-induced testicular alterations.

A neutral polysaccharide from Ophiocordyceps lanpingensis restrains cisplatin-induced nephrotoxicity

Ophiocordyceps lanpingensis is an edible mushroom distributed over the south-eastern part of the Tibet Plateau, which is also recognized as an effective ethnomedicine to alleviate diseases. This study explored the effects of a kind of Ophiocordyceps lanpingensis neutral polysaccharide (ONP) on RAW264.7 macrophages and cisplatin-induced nephrotoxicity. The results showed that ONP relieved the inflammatory response of RAW264.7 macrophages by increasing the expression level of anti-inflammatory factor IL-10. Furthermore, ONP treatment significantly prolonged the survival of the mice treated by cisplatin through decelerating pathological progress and alleviating damaged functions of the kidneys. Compared with the cisplatin group, ONP reduced the oxidative stress of the renal cells and the expression levels of pro-inflammatory factors. Apoptosis of renal cells was also weakened in the ONP treatment group. These findings indicated that ONP alleviated cisplatin nephrotoxicity mainly by inhibiting oxidative stress, inflammation, and apoptosis in the kidneys, underscoring the potential of ONP supplementation to alleviate the side effects of cisplatin chemotherapy.

The Effects on Angiogenesis of Relevant Inorganic Chemotherapeutics

Angiogenesis is a key process allowing the formation of blood vessels. It is crucial for all the tissues and organs, ensuring their function and growth. Angiogenesis is finely controlled by several mechanisms involving complex interactions between pro- or antiangiogenic factors, and an imbalance in this control chain may result in pathological conditions. Metals as copper, zinc and iron cover an essential role in regulating angiogenesis, thus therapies having physiological metals as target have been proposed. In addition, some complexes of heavier metal ions (e.g., Pt, Au, Ru) are currently used as established or experimental anticancer agents targeting genomic or non-genomic targets. These molecules may affect the angiogenic mechanisms determining different effects that have been only poorly and non-systematically investigated so far. Accordingly, in this review article, we aim to recapitulate the impact on the angiogenic process of some reference anticancer drugs, and how it is connected to the overall pharmacological effects. In addition, we highlight how the activity of these drugs can be related to the role of biological essential metal ions. Overall, this may allow a deeper description and understanding of the antineoplastic activity of both approved or experimental metal complexes, providing important insights for the synthesis of new inorganic drugs able to overcome resistance and recurrence phenomena.

Design, physico-chemical characterization and in vitro biological activity of organogold(III) glycoconjugates

To develop new metal-based glycoconjugates as potential anticancer agents, four organometallic gold(iii)-dithiocarbamato glycoconjugates of the type [AuIII(2-Bnpy)(SSC-Inp-GlcN)](PF6) (2-Bnpy: 2-benzylpyridine; Inp: isonipecotic moiety; GlcN: amino-glucose scaffold; Au3-Au6) and the corresponding model non-glycosylated counterparts [AuIII(2-Bnpy)(SSC-Inp-R)](PF6) (R: OEt (Au1), NH2 (Au2)) have been generated and characterized by means of several analytical techniques (elemental analysis, FT-IR, 1H-/13C-NMR, ESI-MS, UV-Vis, X-ray crystallography). Their stability under physiologically-relevant conditions (PBS solution) and n-octanol/PBS distribution coefficient (D7.4) have also been evaluated. Gold(iii) glycoconjugates showed an antiproliferative effect against ovarian carcinoma A2780 cells, with GI50 values in the low micromolar range. Remarkably, their cell growth inhibitory effect increases upon the addition of a glucose transporter 1 (GLUT1) inhibitor, thus ruling out the involvement of GLUT1 in their transport inside the cell. Additional mechanistic studies have been carried out in A2780 cells, supporting the hypothesis of a facilitated diffusion mechanism (possibly mediated by glucose transporters other than GLUT1), and revealing their capability to act as topoisomerase I and II inhibitors and to disrupt mitochondrial membrane integrity, leading to the generation of ROS, thus resulting in the promotion of oxidative stress and, eventually, cell death.

Combined Action of Anti-MUC1 Monoclonal Antibody and Pyrazole-Platinum(II) Complexes Reveals Higher Effectiveness towards Apoptotic Response in Comparison with Monotherapy in AGS Gastric Cancer Cells

MUC1 mucin is a transmembrane glycoprotein aberrantly overexpressed and underglycosylated in most epithelium origin cancers. Combining chemotherapeutics with monoclonal antibodies toward cancer-related antigens is one of the new strategies in cancer therapies. In this study, we assessed the effectiveness of 10 μM cisplatin (cisPt), two pyrazole-platinum(II) complexes (PtPz4 and PtPz6), and 5 μg/mL anti-MUC1 used as monotherapy, as well as cisplatin and its derivatives combined with mAb on apoptotic response and specific cancer-related sugar antigens in AGS gastric cancer cells. Flow cytometry, RT-PCR, Western blotting, and ELISA tests were applied to determine the influence of examined compounds on analyzed factors. PtPz6 combined with anti-MUC1 revealed the strongest apoptotic response compared to control and monotherapy. The combined action of both cisPt derivatives and anti-MUC1 was more effective than monotherapy in relation to Bad, Bcl-xL, Bcl-2, caspase-9, caspase-3, as well as pro- and cleaved caspase-3 protein, and T, sialyl Tn sugar antigens in cell lysates, and Tn, T, sialyl Tn, sialyl T antigens in culture medium. Additionally, PtPz4 administrated with mAb was revealed to be more potent than used alone with regard to Bax protein and Bid expression, and PtPz6 used in complex with anti-MUC1 revealed more efficient action towards Akt and sialyl T antigen expression. These data indicate the rationality of the potential application of combined treatment of anti-MUC1 and cisPt derivatives in gastric cancer therapy.