Lobaplatin: D 19466

Hallmarks of anticancer and antimicrobial activities of corroles

Corroles provide a remarkable opportunity for the development of cancer theranostic agents among other porphyrinoids. While most transition metal corrole complexes are only therapeutic, post-transition metallocorroles also find their applications in bioimaging. Moreover, corroles exhibit excellent photo-physicochemical properties, which can be harnessed for antitumor and antimicrobial interventions. Nevertheless, these intriguing, yet distinct properties of corroles, have not attained sufficient momentum in cancer research. The current review provides a comprehensive summary of various cancer-relevant features of corroles ranging from their structural and photophysical properties, chelation, protein/corrole interactions, to DNA intercalation. Another aspect of the paper deals with the studies of corroles conducted in vitro and in vivo with an emphasis on medical imaging (optical and magnetic resonance), photo/sonodynamic therapies, and photodynamic inactivation. Special attention is also given to a most recent finding that shows the development of pH-responsive phosphorus corrole as a potent antitumor drug for organelle selective antitumor cytotoxicity in preclinical studies. Another biomedical application of corroles is also highlighted, signifying the application of water-soluble and completely lipophilic corroles in the photodynamic inactivation of microorganisms. We strongly believe that future studies will offer a greater possibility of utilizing advanced corroles for selective tumor targeting and antitumor cytotoxicity. In the line with future developments, an ideal pipeline is envisioned on grounds of cancer targeting nanoparticle systems upon decoration with tumor-specific ligands. Hence, we envision that a bright future lies ahead of corrole anticancer research and therapeutics.

Research progress of azido-containing Pt(IV) antitumor compounds

Cancer is a long-known incurable disease, and the medical use of cisplatin has been a significant discovery. However, the side-effects of cisplatin necessitate the development of new and improved drug. Therefore, in this study, we focused on the photoactivatable Pt(IV) compounds Pt[(X₁)(X₂)(Y₁)(Y₂)(N₃)₂], which have a completely novel mechanism of action. Pt(IV) can efficiently overcome the side-effects of cisplatin and other drugs. Here, we have demonstrated, summarized and discussed the effects and mechanism of these compounds. Compared to the relevant articles in the literature, we have provided a more detailed introduction and a made comprehensive classification of these compounds. We believe that our results can effectively provide a reference for the development of these drugs.

Cyclopentadienyl-Based Anticancer Drugs: Improvement of Cytotoxic Activity through Functionalisation of the π Ligand

Cytotoxic complexes containing molybdenum are widely studied as a potential substitution for commercially used drugs that often suffer from pronounced side effects and cellular resistance. Compounds of the type [(η⁵ -Cp')Mo(CO)₂ (^N,N L)][BF₄ ], where Cp is cyclopentadienyl and ^N,N L is a bidentate ligand, are well known for their strong anticancer activity. It is a generally accepted paradigm that the nature of the coordinated ^N,N L ligand has a major impact on the cytotoxicity. In this study, a series of new functionalised Cp complexes of molybdenum was synthesised from derivatised fulvenes as π-ligand precursors. Indeed, the coordination sphere's modulation by various N,N-chelating ligands afforded species active toward leukemic cell line MOLT-4 with IC₅₀ values depending on the character of the N,N-chelator used. However, following study clearly showed that functionalisation of the Cp ring with an amine moiety considerably improved cytotoxicity. These results are of crucial importance for the future design of highly active cytotoxic drugs, as modification of cyclopentadienyl is believed to have a minor effect on biological activity.

Retrospective study of the efficacy and toxicity of lobaplatin in combined chemotherapy for metastatic breast cancer

OBJECTIVE

To study the efficacy and adverse reactions of lobaplatin combined with other chemotherapy drugs in the treatment of metastatic breast cancer.

METHODS

This retrospective analysis enrolled 114 patients who were diagnosed with advanced breast cancer from January 2010 to December 2015. Lobaplatin and another chemotherapeutic agent were given to patients. The efficacy and side effects were evaluated after at least two cycles of chemotherapy.

RESULTS

Therapeutic efficacy and adverse reactions could be evaluated in 112 patients with 2 complete response (CR) patients, 31 cases of partial response (PR), 52 cases of stable disease (SD) and 27 cases of progressive disease (PD). The overall response rate (ORR) was 29.5% and the disease control rate (DCR) was 75.9%. The median time to progression (TTP) was 7.7 months, and the median overall survival (OS) was expected to be 28.0 months. The main side effects were myelosuppression. Twenty five patients (21.9%) had grade 3/4 neutrophil suppression, 18 patients (15.8%) had grade 3/4 thrombocytopenia. Other toxicities included gastrointestinal reaction, peripheral neuropathy, stomatitis, hepatic dysfunction, fatigue and skin rashes, which were alleviated by symptomatic treatment.

CONCLUSION

Lobaplatin-based regimen chemotherapy for advanced metastatic breast cancer patients is effective and well tolerated.

Lobaplatin Inhibits Prostate Cancer Proliferation and Migration Through Regulation of BCL2 and BAX

Lobaplatin is a diastereometric mixture of platinum (II) complexes, which contain a 1,2-bis (aminomethyl) cyclobutane stable ligand and lactic acid. Previous studies have showed that lobaplatin plays inhibiting roles in various types of tumors. However, the role of lobaplatin in prostate cancer remains unknown. Cell viability was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Cell proliferation was detected by cell colony formation assay. Cell migration and invasion were determined by transwell migration and invasion assay. Cell apoptosis was detected by flow cytometry. The messenger RNA and protein expression levels were detected by quantitative real-time polymerase chain reaction and Western blot. Lobaplatin treatment inhibits cell viability, cell proliferation, cell migration, and invasion, while promotes cell apoptosis of prostate cancer cell lines DU145 and PC3. Meanwhile, lobaplatin treatment regulates apoptosis by downregulation of BCL2 expression and upregulation of BAX expression levels. Our study suggests lobaplatin inhibits prostate cancer proliferation and migration through regulation of BCL2 and BAX expression.

Population pharmacokinetics and individualized lobaplatin regimen for the treatment of Chinese small cell lung cancer in the elderly

BACKGROUND

Lobaplatin (LBP) is a third-generation platinum compound.

MATERIAL AND METHODS

This prospective study was performed in 7 institutions in 2014-2016. Elderly small cell lung cancer (SCLC) patients (≥65 years old) were divided into 2 groups to receive LBP regimens according to endogenous creatinine clearance rate (Ccr). LBP was administered at 30 and 20 mg/m in groups A (Ccr ≥ 80 ml/min) and B (60 ml/min ≤ Ccr < 80 ml/min), respectively. The primary endpoint was plasma LBP concentrations. Secondary endpoints were safety and efficacy parameters, including progression-free survival (PFS) and overall survival (OS).

RESULTS

One-hundred patients were enrolled. Median PFS and OS in groups A and B were 155 vs170 days and 306 vs 272 days, respectively. The rates of grade III/IV AEs in groups A and B were 60.8% (n = 31) and 51.0% (n = 25), respectively. In population pharmacokinetics, the area under the curve (AUC) value for group B was 39% lower than that of group A. With LBP administration based on body surface area (BSA), AUC differences between individuals were small.

CONCLUSION

With Ccr ≥ 60 ml/min, BSA based administration is necessary. Meanwhile, LBP-based regimens are reliable in treating elderly patients with SCLC.

Lobaplatin suppresses proliferation and peritoneal metastasis of colorectal cancer in a preclinical model

Peritoneal metastasis from colorectal cancer (CRC) is related to poor prognosis. Intraperitoneal chemotherapy is an efficient method to treat peritoneal metastasis (PM); however, the outcomes remain unsatisfactory. The present study aimed to investigate the antitumor activity of lobaplatin and its role in intraperitoneal chemotherapy. The findings showed that the proliferation of CRC was inhibited in a dose-dependent manner when DLD1 and HCT116 cells were treated with various concentrations of lobaplatin (0, 6.3, 12.5, 25, 50, and 100 μg/mL, respectively). Flow cytometry and Western blot analysis confirmed that lobaplatin affected CRC cells by inducing apoptosis and modulating the caspase family. In the animal study, nude mice were injected with DLD1 cells and divided into three groups. Lobaplatin was injected intraperitoneally to simulate intraperitoneal chemotherapy. Group A was the control group treated with PBS. Group B was injected with DLD1 and treated with lobaplatin simultaneously, while group C was treated with lobaplatin 1 week after cell injection. The results showed that group A harbored maximal tumors on the peritoneal surface, while group B had the least number (9.2 ± 1.3 and 0.4 ± 0.5, respectively P < 0.01). These findings indicated that lobaplatin suppressed the tumor growth as an intraperitoneal chemotherapy agent and achieved a satisfactory therapeutic effect at an early stage. Further blood test and tissue staining did not reveal any liver and kidney toxicity that was induced by lobaplatin. In conclusion, lobaplatin could be an effective and safe agent for CRC treatment, thereby commissioning a novel strategy in intraperitoneal chemotherapy for patients with peritoneal metastasis.

Poly ADP-ribose polymerase inhibition suppresses cisplatin toxicity in chronic myeloid leukemia cells

Cancer cells may acquire drug resistance by activating DNA repair signaling. Poly ADP-ribose polymerase (PARP) plays an important role in DNA repair and it is overexpressed in many cancers including chronic myeloid leukemia (CML). PARP inhibitors have been used either alone or with other drugs to augment cancer cell death. However, whether PARP inhibitors may also augment cell death induced by chemotherapeutic agents in CML cells has not been studied. K562 cells with or without PARP-1 knockdown were treated with cisplatin alone or together with olaparib. The cell death was investigated by propidium iodide staining and apoptosis-related proteins were detected by western blotting. Olaparib suppressed cisplatin-induced cell death in K562 and MEG01 cells. Moreover, PARP-1 knockdown also attenuated cisplatin toxicity in CML cells. Inhibition of PARP decreased cisplatin toxicity by attenuating caspase-3 and caspase-9 activity. These results indicated that the toxicity of cisplatin in CML cells requires PARP activity. Therefore, PARP inhibitors may not be useful with DNA-damaging agents such as cisplatin in CML treatment.

Platinum, palladium, gold and ruthenium complexes as anticancer agents: Current clinical uses, cytotoxicity studies and future perspectives

Metallodrugs offer potential for unique mechanism of drug action based on the choice of the metal, its oxidation state, the types and number of coordinated ligands and the coordination geometry. This review illustrates notable recent progress in the field of medicinal bioinorganic chemistry as many new approaches to the design of innovative metal-based anticancer drugs are emerging. Current research addressing the problems associated with platinum drugs has focused on other metal-based therapeutics that have different modes of action and on prodrug and targeting strategies in an effort to diminish the side-effects of cisplatin chemotherapy. Examples of metal compounds and chelating agents currently in clinical use, clinical trials or preclinical development are highlighted.

The Next Generation of Platinum Drugs: Targeted Pt(II) Agents, Nanoparticle Delivery, and Pt(IV) Prodrugs

The platinum drugs, cisplatin, carboplatin, and oxaliplatin, prevail in the treatment of cancer, but new platinum agents have been very slow to enter the clinic. Recently, however, there has been a surge of activity, based on a great deal of mechanistic information, aimed at developing nonclassical platinum complexes that operate via mechanisms of action distinct from those of the approved drugs. The use of nanodelivery devices has also grown, and many different strategies have been explored to incorporate platinum warheads into nanomedicine constructs. In this Review, we discuss these efforts to create the next generation of platinum anticancer drugs. The introduction provides the reader with a brief overview of the use, development, and mechanism of action of the approved platinum drugs to provide the context in which more recent research has flourished. We then describe approaches that explore nonclassical platinum(II) complexes with trans geometry or with a monofunctional coordination mode, polynuclear platinum(II) compounds, platinum(IV) prodrugs, dual-threat agents, and photoactivatable platinum(IV) complexes. Nanoparticles designed to deliver platinum(IV) complexes will also be discussed, including carbon nanotubes, carbon nanoparticles, gold nanoparticles, quantum dots, upconversion nanoparticles, and polymeric micelles. Additional nanoformulations, including supramolecular self-assembled structures, proteins, peptides, metal-organic frameworks, and coordination polymers, will then be described. Finally, the significant clinical progress made by nanoparticle formulations of platinum(II) agents will be reviewed. We anticipate that such a synthesis of disparate research efforts will not only help to generate new drug development ideas and strategies, but also will reflect our optimism that the next generation of approved platinum cancer drugs is about to arrive.

Advances in drug delivery system for platinum agents based combination therapy

Platinum-based anticancer agents are widely used as first-line drugs in cancer chemotherapy for various solid tumors. However, great side effects and occurrence of resistance remain as the major drawbacks for almost all the platinum drugs developed. To conquer these problems, new strategies should be adopted for platinum drug based chemotherapy. Modern nanotechnology has been widely employed in the delivery of various therapeutics and diagnostic. It provides the possibility of targeted delivery of a certain anticancer drug to the tumor site, which could minimize toxicity and optimize the drug efficacy. Here, in this review, we focused on the recent progress in polymer based drug delivery systems for platinum-based combination therapy.

Lobaplatin-TACE combined with radioactive 125I seed implantation for treatment of primary hepatocellular carcinoma

AIM

To investigate the efficacy and safety of lobaplatin-transcatheter arterial chemoembolization (TACE) combined with radioactive 125I seed implantation in treatment of primary hepatocellular carcinoma (HCC).

METHODS

75 patients with primary HCC were enrolled in the study, among them 43 receiving lobaplatin- TACE (TACE group) and 32 lobaplatin-TACE combined with 125I seed implantation (TACE+125I group). After treatment, the local remission rates and postoperative complications of two groups were compared using the Pearson Chi-square test. Overall survival in the two groups was calculated using Kaplan-Meier survival curves and the differences were tested using Log-rank test.

RESULTS

There were 7 cases of complete response (CR), 13 of partial response (PR), 6 of stable disease (SD) and 17 of progressive disease (PD) in the TACE group, with 13 cases of CR, 9 of PR, 5 of SD and 5 of PD in the TACE+125I group. The disease control rates of TACE and TACE+125I group were 60.5% (26/43) and 84.4% (27/32), respectively, with a significant difference between them (P < 0.05). The survival rates at 6, 12 and 18 months in the TACE group were 100.0%, 81.8% and 50.0%, respectively, and those in TACE+125I group were 100.0%, 93.8% and 65.6%. The mean survival times in the TACE and TACE+125I groups were 19.5 and 22.9 months, respectively. There was a significant difference in the overall survival rate between two groups (P < 0.05). No serious complications were encountered in either group.

CONCLUSION

Lobaplatin-TACE combined with 125I seed implantation is favorable and safe for treatment of primary HCC.

Assessment of new DFT methods for predicting vibrational spectra and structure of cisplatin: which density functional should we choose for studying platinum(II) complexes?

Ten different DFT methods, including several recently developed functionals have been tested for their performances in prediction of infrared and Raman spectra and molecular structure of cisplatin. The assessed DFT methods cover the range from meta-GGA to hybrid, double hybrid and long-range corrected hybrid models (M06-L, M06, M06-2X, PBE0, mPW1PW, B3LYP, B2PLYP, CAM-B3LYP, ωB97XD and LC-ωPBE). The calculated structural parameters and theoretical spectra have been compared to the corresponding experimental data. It is shown that the LC-ωPBE scheme is superior to other DFT methods in predicting the geometry of cisplatin. Unfortunately, the M06-L, M06-2X and B3LYP functionals are deficient in the evaluation of the strength of two Pt←NH3 coordination bonds in cisplatin (the calculated bond lengths are too long and the Pt-N stretching frequencies are underestimated). Both the PBE0 and mPW1PW functionals, in conjunction with the LanL2TZ(f) basis set for Pt give very similar theoretical results and seem to be the best methods for predicting the IR and Raman spectra of cisplatin. The long-range corrected functionals (LC-ωPBE, ωB97XD and CAM-B3LYP) have shown good performances in predicting the frequencies of Pt-ligand vibrations and are promising new tools for theoretical study of novel platinum(II) compounds.

The status of platinum anticancer drugs in the clinic and in clinical trials

Since its approval in 1979 cisplatin has become an important component in chemotherapy regimes for the treatment of ovarian, testicular, lung and bladder cancers, as well as lymphomas, myelomas and melanoma. Unfortunately its continued use is greatly limited by severe dose limiting side effects and intrinsic or acquired drug resistance. Over the last 30 years, 23 other platinum-based drugs have entered clinical trials with only two (carboplatin and oxaliplatin) of these gaining international marketing approval, and another three (nedaplatin, lobaplatin and heptaplatin) gaining approval in individual nations. During this time there have been more failures than successes with the development of 14 drugs being halted during clinical trials. Currently there are four drugs in the various phases of clinical trial (satraplatin, picoplatin, Lipoplatin and ProLindac). No new small molecule platinum drug has entered clinical trials since 1999 which is representative of a shift in focus away from drug design and towards drug delivery in the last decade. In this perspective article we update the status of platinum anticancer drugs currently approved for use, those undergoing clinical trials and those discontinued during clinical trials, and discuss the results in the context of where we believe the field will develop over the next decade.