Phase II trial of pyrazoloacridine (NSC#366140) in patients with metastatic breast cancer

Pyrazoline Containing Compounds as Therapeutic Targets for Neurodegenerative Disorders

Pyrazolines are a significant class of heterocyclic compounds with essential biological activities. They are quite stable, which has inspired medicinal chemists to experiment with the ring's structure in many different ways to create a variety of pharmacological activities. The structures of numerous commercially available therapeutic agents contain a pyrazoline ring. Pyrazolines are well-known for their ability to treat neurodegenerative diseases. The neurodegenerative diseases that affect huge populations globally include Alzheimer's disease (AD), Parkinson's disease (PD), and psychiatric disorders. The neuroprotective properties of pyrazolines published since 2003 are covered in the current review. Structure-activity relationships (SARs), molecular docking simulation, anticholinesterase (anti-AChE), and monoamine oxidase (MAO A/B) inhibitory actions are all covered in this article. Pyrazolines were discovered to have beneficial effects in the management of AD and were revealed to be inhibitors of acetylcholine esterase (AChE) and beta-amyloid (Aβ) plaques. They were discovered to be efficient against PD and also targeted MAO B and COMT. It was discovered that the pyrazolines block MAO A to treat psychiatric diseases. Pyrazolines are significant heteroaromatic scaffolds with a variety of biological functions. They were discovered to be remarkably stable and serve as an indispensable anchor for the development of new drugs. By blocking AChE and MAOs, they may be used to treat neurodegenerative diseases. The discussion outlined here is an essential and helpful resource for medicinal chemists who are investigating and applying pyrazolines in neurodegenerative research initiatives as well as to expedite future research programs on neurodegenerative disorders.

CCNA2 as an Immunological Biomarker Encompassing Tumor Microenvironment and Therapeutic Response in Multiple Cancer Types

Background

Cancer is a major threat to human health worldwide. Although recent innovations and advances in early detection and effective therapies such as targeted drugs and immune checkpoint inhibitors have saved more lives of cancer patients and improved their quality of life, our knowledge about cancer remains largely unknown. CCNA2 belongs to the cell cyclin family and has been demonstrated to be a tumorigenic gene in multiple solid tumor types. The aim of the present study was to make a comprehensive analysis on the role of CCNA2 at a pancancer level.

Methods

Multidatabases were collected to evaluate the different expression, prognostic value, DNA methylation, tumor mutation burden, microsatellite instability, mismatch repair, tumor immune microenvironment, and drug sensitivity of CCNA2 across pancancer. IHC was utilized to validate the expression and prognostic value of CCNA2 in ccRCC patients from SMMU cohort.

Results

CCNA2 was differentially expressed in most cancer types vs. normal tissues. CCNA2 may significantly influence the prognosis of multiple cancer types, especially clear cell renal cell carcinoma (ccRCC). CCNA2 was also frequently mutated in most cancer types. Notably, CCNA2 was significantly correlated with immune cell infiltration and immune checkpoint inhibitory genes. In addition, CCNA2 was also strongly related to drug resistance.

Conclusion

CCNA2 may prove to be a new biomarker for prognostic prediction, tumor immunity assessment, and drug susceptibility evaluation in pancancer level, especially in ccRCC.

The Novel Dual Topoisomerase Inhibitor P8-D6 Shows Anti-myeloma Activity In Vitro and In Vivo

P8-D6 is a novel dual inhibitor of human topoisomerase I (TOP1) and II (TOP2) with broad pro-apoptotic antitumor activity. NCI-60 screening revealed markedly improved cytotoxicity of P8-D6 against solid and leukemia cell lines compared with other single and dual topoisomerase inhibitors, for example, irinotecan, doxorubicin, or pyrazoloacridine. In this study, we investigated the capacity of P8-D6 to inhibit myeloma cell growth in vitro and in vivo Growth inhibition assays demonstrated significant anti-myeloma effects against different myeloma cell lines with IC₅₀ values in the low nanomolar range. Freshly isolated plasma cells of patients with multiple myeloma were killed by P8-D6 with similar doses. P8-D6 activated caspase 3/7 and induced significant apoptosis of myeloma cells. Supportive effects of bone marrow stromal cells on IL6-dependent INA-6 myeloma cells were abrogated by P8-D6 and apoptosis occurred in a time- and dose-dependent manner. Of note, healthy donor peripheral blood mononuclear cells and human umbilical vein endothelial cells were not affected at concentrations toxic for malignant plasma cells. Treatment of myeloma xenografts in immunodeficient SCID/beige mice by intravenous and, notably, also oral application of P8-D6 markedly inhibited tumor growths, and significantly prolonged survival of tumor-bearing mice.

Pharmacophore hybridization approach to discover novel pyrazoline-based hydantoin analogs with anti-tumor efficacy

In search for new and safer anti-cancer agents, a structurally guided pharmacophore hybridization strategy of two privileged scaffolds, namely diaryl pyrazolines and imidazolidine-2,4-dione (hydantoin), was adopted resulting in a newfangled series of compounds (H1-H22). Herein, a bio-isosteric replacement of "pyrrolidine-2,5-dione" moiety of our recently reported antitumor hybrid incorporating diaryl pyrazoline and pyrrolidine-2,5-dione scaffolds with "imidazoline-2,4-dione" moiety has been incorporated. Complete biological studies revealed the most potent analog among all i.e. compound H13, which was at-least 10-fold more potent compared to the corresponding pyrrolidine-2,5-dione, in colon and breast cancer cells. In-vitro studies showed activation of caspases, arrest of G0/G1 phase of cell cycle, decrease in the expression of anti-apoptotic protein (Bcl-2) and increased DNA damage. In-vivo assay on HT-29 (human colorectal adenocarcinoma) animal xenograft model unveiled the significant anti-tumor efficacy along with oral bioavailability with maximum TGI 36% (i.p.) and 44% (per os) at 50 mg/kg dose. These findings confirm the suitability of hybridized pyrazoline and imidazolidine-2,4-dione analog H13 for its anti-cancer potential and starting-point for the development of more efficacious analogs.

Synthesis, Biological Evaluation and Stability Studies of Some Novel Aza-Acridine Aminoderivatives

Several new amino-substituted aza-acridine derivatives bearing a basic side chain have been designed and synthesized. The antiproliferative activity of the target compounds has been evaluated against three cancer cell lines-namely HCT-116 (colorectal), the uterine sarcoma MES-SA, and its doxorubicin-resistant variant MES-SA/Dx5. A limited number of the new acridines showed marginal cytotoxicity against the tested cell lines; nevertheless, these analogues possessed a similar substitution pattern. The moderate biological activity of these derivatives was attributed to their instability in aqueous media, which has been studied by mass spectrometry and computational chemistry experiments at the density functional level of theory (DFT).

Recent advancements in the development of bioactive pyrazoline derivatives

Pyrazolines remain privileged heterocycles in drug discovery. 2-Pyrazoline scaffold has been proven as a ubiquitous motif which is present in a number of pharmacologically important drug molecules such as antipyrine, ramifenazone, ibipinabant, axitinib etc. They have been widely explored by the scientific community and are reported to possess wide spectrum of biological activities. For combating unprecedented diseases and worldwide increasing drug resistance, 2-pyrazoline has been tackled as a fascinating pharmacophore to generate new molecules with improved potency and lesser toxicity along with desired pharmacokinetic profile. This review aims to summarizes various recent advancements in the medicinal chemistry of pyrazoline based compounds with the following objectives: (1) To represent inclusive data on pyrazoline based marketed drugs as well as therapeutic candidates undergoing preclinical and clinical developments; (2) To discuss recent advances in the medicinal chemistry of pyrazoline derivatives with their numerous biological significances for the eradication of various diseases; (3) Summarizes structure-activity relationships (SAR) including in silico and mechanistic studies to afford ideas for the design and development of novel compounds with desired therapeutic implications.

The Aza-Analogous Benzo[c]phenanthridine P8-D6 Acts as a Dual Topoisomerase I and II Poison, thus Exhibiting Potent Genotoxic Properties

The benzo[c]phenanthridine P8-D6 was recently found to suppress the catalytic activity of both human topoisomerase (Topo) I and II. Concomitantly, potent cytotoxic activity was observed in different human tumor cell lines, raising questions about the underlying mechanisms in vitro. In the present study, we addressed the question of whether P8-D6 acts as a so-called Topo poison, stabilizing the covalent Topo-DNA intermediate, thus inducing fatal DNA strand breaks in proliferating cells. In HT-29 colon carcinoma cells, fluorescence imaging revealed P8-D6 to be taken up by the cells and to accumulate in the perinuclear region. Confocal microscopy demonstrated that the compound is partially located inside the nuclei, thus reaching the potential target. In the "in vivo complex of enzyme" (ICE) bioassay, treatment of HT-29 cells with P8-D6 for 1 h significantly enhanced the proportion of Topo I and II covalently linked to the DNA in concentrations ≥1 µM, indicating effective dual Topo poisoning. Potentially resulting DNA damage was analyzed by single-cell gel electrophoresis ("comet assay"). Already at 1 h of incubation, significant genotoxic effects were observed in the comet assay in concentrations as low as 1 nM. Taken together, the present study demonstrates the high Topo-poisoning and genotoxic potential of P8-D6 in human tumor cells.

Design, synthesis, molecular modelling, and biological evaluation of novel substituted pyrimidine derivatives as potential anticancer agents for hepatocellular carcinoma

New anticancer agents are highly needed to overcome cancer cell resistance. A novel series of pyrimidine pyrazoline-anthracene derivatives (PPADs) (4a-t) were designed and synthesised. The anti-liver cancer activity of all compounds was screened in vitro against two hepatocellular carcinoma (HCC) cell lines (HepG2 and Huh-7) as well as normal fibroblast cells by resazurin assay. The designed compounds 4a-t showed a broad-spectrum anticancer activity against the two cell lines and their activity was more prominent on cancer compared to normal cells. Compound 4e showed high potency against HepG2 and Huh-7 cell lines ((IC₅₀=5.34 and 6.13 μg/mL, respectively) comparable to that of doxorubicin (DOX) activities. A structure activity relationship (SAR) has been investigated and compounds 4e, 4i, 4m, and 4q were the most promising anticancer agents against tested cell lines. These compounds induced apoptosis in HepG2 and Huh-7 cells through significant activation of caspase 3/7 at all tested concentrations. In conclusion, 4e could be a potent anticancer drug.

A New Series of Cytotoxic Pyrazoline Derivatives as Potential Anticancer Agents that Induce Cell Cycle Arrest and Apoptosis

A new series of pyrazoline derivatives 1b-12b was designed, synthesized and evaluated for antiproliferative activity against three cancer cell lines (HepG-2, Hela and A549). Additionally, NIH/3T3 cell cytotoxicity were tested and the structure activity relationships (SARs) were also determined. Among these new derivatives, the compounds 3-(4-fluorophenyl)-5-(3,4,5-trimethoxythiophenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide (1b) and 3-(4-chlorophenyl)-5-(3,4,5-trimethoxythiphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide (2b) showed the best activity against HepG-2 cells, with IC₅₀ values of 6.78 μM and 16.02 μM, respectively. They also displayed potent activity against Hela cells; meanwhile, 3-(4-chlorophenyl)-5-(3-bromo-4-hydroxy-5-methoxythiophenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide (5b) and 3-(4-bromo-phenyl)-5-(3-bromo-4-hydroxy-5-methoxythiophenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide (6b) were also identified as promising anticancer agents against A549 cells owing to their notable inhibitory effect, compared with cisplatin (IC₅₀ = 29.48 μM). Furthermore, it was also found that compounds 1b and 2b had low cytotoxicity against NIH/3T3 cells and further mechanistic studies revealed that 1b arrested HepG-2 cells cycle at the G2/M phase at high concentrations and induced apoptosis in HepG-2 cells. Moreover, 1b upregulated protein expression level of cleaved caspase-3, cleaved PARP, Bax and p53 and downregulated protein expression level of Bcl-2 in dose-dependent way in HepG-2 cells. Thus, this study indicates that compound 1b might be a promising antitumor drug candidate.

Synthesis and Evaluation of New Pyrazoline Derivatives as Potential Anticancer Agents in HepG-2 Cell Line

Cancer is a major public health concern worldwide. Adverse effects of cancer treatments still compromise patients' quality of life. To identify new potential anticancer agents, a series of novel pyrazoline derivatives were synthesized and evaluated for cytotoxic effects on HepG-2 (human liver hepatocellular carcinoma cell line) and primary hepatocytes. Compound structures were confirmed by ¹H-NMR, mass spectrometry, and infrared imaging. An in vitro assay demonstrated that several compounds exerted cytotoxicity in the micromolar range. Benzo[b]thiophen-2-yl-[5-(4-hydroxy-3,5-dimethoxy-phenyl)-3-(2-hydroxy-phenyl)-4,5-dihydo-pyrazol-1-yl]-methanone (b17) was the most effective anticancer agent against HepG-2 cells owing to its notable inhibitory effect on HepG-2 with an IC₅₀ value of 3.57 µM when compared with cisplatin (IC₅₀ = 8.45 µM) and low cytotoxicity against primary hepatocytes. Cell cycle analysis and apoptosis/necrosis evaluation using this compound revealed that b17 notably arrested HepG-2 cells in the G₂/M phase and induced HepG-2 cells apoptosis. Our findings indicate that compound b17 may be a promising anticancer drug candidate.

Acridine and its derivatives: a patent review (2009 - 2013)

INTRODUCTION

Acridine derivatives have been extensively explored as potential therapeutic agents for the treatment of a number of diseases, such as cancer, Alzheimer's, and bacterial and protozoan infections. Their mode of action is mainly attributed to DNA intercalation and the subsequent effects on the biological processes linked to DNA and its related enzymes.

AREA COVERED

This review covers the relevant efforts in developing acridine derivatives with enhanced therapeutic potency and selectivity and as fluorescent materials, with particular focus on the newly patented acridine derivatives in 2009 - 2013, acridine drugs in clinical trials and preclinical studies, and other new derivatives that emerged in 2009 - 2013.

EXPERT OPINION

Thousands of acridines with therapeutic and biological activities or with photochemical properties have been developed. In addition, to modify the position and the nature of the substituent on the acridine core, more attention may be paid to the development of azaacridine or other heteroatom-substituted acridine derivatives and their synthesis methods to broaden the application of acridine derivatives. In cancer chemotherapy, the mode of action of acridine derivatives needs to be further studied. Efficient methods for identification and optimization of acridine derivatives to localize at the sites of disease need to be further developed. Moreover, acridine drugs may be combined with such bioactive agents as DNA repair proteins inhibitors to overcome tumor resistance and improve outcomes.

Emerging drugs in metastatic breast cancer: an update

INTRODUCTION

The incidence of breast cancer at an advanced stage has decreased in the modern world due to screening programs and usage of novel chemotherapy agents at an adjuvant setting. Recurrence is the major problem seen in > 50% of breast cancer patients diagnosed at an early stage. Developing new drugs for metastatic breast cancer is a huge and challenging research area.

AREAS COVERED

Emerging drugs showed positive results in clinical studies and agents in routine clinical usage are updated. Current treatment strategies as a combination of biologic agents and overcoming drug resistance are discussed. Literature search is made from PubMed, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts.

EXPERT OPINION

A number of drugs caused survival benefit for advanced breast cancer. Hundreds of new studies with tens of agents are conducted for treatment of metastatic breast cancer. Tumor resistance and treatment related toxicities are unavoidable which are two main search areas for improving metastatic breast cancer management. Understanding the pathways of genesis and progression yielded many targets for treatment. However, cure in metastatic breast cancer is still a far aim and new agents and treatment strategies are needed.