Discovery of a SHP2 Degrader with In Vivo Anti-Tumor Activity

Src homology 2 domain-containing phosphatase 2 (SHP2) is an attractive target for cancer therapy due to its multifaceted roles in both tumor and immune cells. Herein, we designed and synthesized a novel series of proteolysis targeting chimeras (PROTACs) using a SHP2 allosteric inhibitor as warhead, with the goal of achieving SHP2 degradation both inside the cell and in vivo. Among these molecules, compound P9 induces efficient degradation of SHP2 (DC50 = 35.2 ± 1.5 nM) in a concentration- and time-dependent manner. Mechanistic investigation illustrates that the P9-mediated SHP2 degradation requires the recruitment of the E3 ligase and is ubiquitination- and proteasome-dependent. P9 shows improved anti-tumor activity in a number of cancer cell lines over its parent allosteric inhibitor. Importantly, administration of P9 leads to a nearly complete tumor regression in a xenograft mouse model, as a result of robust SHP2 depletion and suppression of phospho-ERK1/2 in the tumor. Hence, P9 represents the first SHP2 PROTAC molecule with excellent in vivo efficacy. It is anticipated that P9 could serve not only as a new chemical tool to interrogate SHP2 biology but also as a starting point for the development of novel therapeutics targeting SHP2.

Piperlongumine Induces Apoptosis and Cytoprotective Autophagy via the MAPK Signaling Pathway in Human Oral Cancer Cells

Oral cancer is a malignant tumor that primarily affects areas such as the lips, tongue, buccal mucosa, salivary gland, and gingiva and has a very high malignancy. Piperlongumine (PL), isolated from long pepper (Piper longum L.), is a natural alkaloid with pharmacological effects, such as anti-inflammatory and anti-atherosclerotic effects. The effect and mechanism of PL in oral cancer cell lines has not been explored. Therefore, this study aimed to investigate the mechanism of anticancer effects of PL in the human oral cancer cell lines MC-3 and HSC-4 in vitro. This study demonstrated that PL inhibits cell proliferation by inducing apoptosis and autophagy in human oral cancer cell lines, which was confirmed by the levels of apoptosis- and autophagy-related proteins through Western blotting. Moreover, the pharmacological blockade of autophagy activation by hydroxychloroquine (HCQ), an autophagy inhibitor, significantly improved PL-induced apoptosis in MC-3 cells, suggesting a cytoprotective effect. In addition, activation of the mitogen-activated protein kinase (MAPK) signaling pathway contributed to PL-induced apoptosis. Collectively, the study suggested that combining an autophagy inhibitor with PL treatment can exert effective anticancer properties in oral cancer cells by inducing apoptosis and cytoprotective autophagy via the JNK-mediated MAPK pathway.

Design, Synthesis and Biological Evaluation of Multi-Target Anti-Cancer Agent PYR26

This study investigates the synthesis of a new compound, PYR26, and the multi-target mechanism of PYR26 inhibiting the proliferation of HepG2 human hepatocellular carcinoma cells. PYR26 significantly inhibits the growth of HepG2 cells (p < 0.0001) and this inhibition has a concentration effect. There was no significant change in ROS release from HepG2 cells after PYR26 treatment. The mRNA expressions of CDK4, c-Met and Bak genes in HepG2 cells were significantly inhibited (p < 0.05), while mRNA expression of pro-apoptotic factors such as caspase-3 and Cyt c was significantly increased (p < 0.01). The expression of PI3K, CDK4 and pERK proteins decreased. The expression level of caspase-3 protein was increased. PI3K is a kind of intracellular phosphatidylinositol kinase. PI3K signaling pathway is involved in signal transduction of a variety of growth factors, cytokines and extracellular matrix and plays an important role in preventing cell apoptosis, promoting cell survival and influencing cell glucose metabolism. CDK4 is a catalytic subunit of the protein kinase complex and is important for G1 phase progression of the cell cycle. PERK refers to phosphorylated activated ERK, which is translocated from cytoplasm to the nucleus after activation, and then participates in various biological reactions such as cell proliferation and differentiation, cell morphology maintenance, cytoskeleton construction, cell apoptosis and cell canceration. Compared with the model group and the positive control group, the tumor volume of the nude mice in the low-concentration PYR26 group, the medium-concentration group and the high-concentration group was smaller, and the organ volume was smaller than that in the model group and the positive control group. The tumor inhibition rates of low-concentration group PYR26, medium-concentration group and high-concentration group reached 50.46%, 80.66% and 74.59%, respectively. The results showed that PYR26 inhibited the proliferation of HepG2 cells and induced apoptosis of HepG2 cells by down-regulating c-Met, CDK4 and Bak, up-regulating the mRNA expression of caspase-3 and Cyt c genes, down-regulating PI3K, pERK and CDK4 proteins and up-regulating the protein level of caspase-3. In a certain range, with the increase in PYR26 concentration, the tumor growth was slower and the tumor volume was smaller. Preliminary results showed that PYR26 also had an inhibitory effect on the tumors of Hepa1-6 tumor-bearing mice. These results suggest that PYR26 has an inhibitory effect on the growth of liver cancer cells, therefore it has potential to be developed into a new anti-liver cancer drug.

[Education Aimed at Patient Safety Management of Chemotherapy Conducted at University Education Sites]

The School Education Law was revised in 2006, and the university pharmacy education system and the national pharmacist examination system were changed. In line with the advancement of medical technology and the division of labor, 16 years have passed since the length of undergraduate pharmacy education was extended from 4 to 6 years in order to foster highly qualified pharmacists. During this period, the curriculum for practical training has been revised, and lectures and exercises focused on clinical education have been incorporated to foster pharmacists who can be useful in the medical field. In the area of cancer drug therapy, the university provides students with opportunities to learn about the basic mechanisms of action and side effects of anticancer drugs, but there is little coverage of clinical guidelines and pharmacological management of the latest therapies, such as cancer immunotherapy. Prior to my arrival at Hoshi University, I was involved in clinical work and clinical research at an oncology hospital for 13 years. Since my arrival, I have been exploring the gap between oncology pharmacotherapy and pharmacy education, and have been working to fill it. We have incorporated new curricula, such as exercises in formulation suggestions, lectures to deepen understanding of guidelines and supportive care, and information on the latest cancer drug therapies, such as cancer immunotherapy. This paper outlines the pharmacy education required to produce pharmacists who can practice safe cancer drug therapy.

In Silico Optimization of Frizzled-8 Receptor Inhibition Activity of Carbamazepine: Designing New Anti-Cancer Agent

BACKGROUND

Frizzled-8 (FZD8) receptor is a therapeutic target for cancer treatment and recent research has shown that carbamazepine (CBZ) can inhibit this receptor.

OBJECTIVE

In this work, it has been tried to optimize CBZ to enhance its binding capacity to the N6W binding site of FZD8 by using structure-based drug design methods.

METHODS

CBZ and its 83 derivatives were docked to the N6W binding site of FZD8.

RESULTS

Docking results show that two compounds 79 and 82 have the smallest binding energies and are fitted to the N6W binding site. Compounds C79 and C82 have been synthesized by replacing a hydrogen atom of the seven-membered ring in CBZ with benzoate and nicotinate groups, respectively. In addition, docking results show that a trifluoromethyl on one of the phenyl rings is favorable for improving the FZD8 inhibition activity of the molecule.

CONCLUSION

Both molecules C79 and C82 were subjected to molecular dynamics (MD) simulation. MD results show that FZD8-C82 complex is stable and this compound binds to the N6W binding site more strongly than compounds C79 and CBZ.

Binding characterization of anthraquinone derivatives by stabilizing G-quadruplex DNA leads to an anticancerous activity

G-quadruplex is a non-canonical secondary structure identified in the telomeric region and the promoter of many oncogenes. Anthraquinone derivatives, a well-known inducer of telomere disruption in malignant cells and activate the apoptotic pathway. We used biophysical and biochemical studies to confirm the interaction of synthesized anthraquinone derivatives with the human telomeric G-quadruplex sequence. The binding affinity of N-2DEA and N-1DEA are K _b = 4.8 × 10⁶ M^-1 and K _b = 7.6 × 10⁵ M^-1, respectively, leading to hypochroism, fluorescence quenching with minor redshift and ellipticity variations indicating ligand binding in the external groove. We found that sodium ions induced stabilization more rather than potassium ions. Molecular docking of complex demonstrates a molecule's exterior binding to a quadruplex. The investigation of ROS activity indicated that the cell initiates mortality in response to the IC₅₀ concentration. Cellular morphology, nuclear condensation, and fragmentation were altered in the treated cell, impairing cellular function. Finally, the transcriptional regulatory study paves the way for drug design as an anti-cancer agent because of the tremendous possibilities of changing substituent groups on anthraquinones to improve efficacy and selectivity for G-quartet DNA. Our research focused on how ligand binding to telomere sequences induces oxidative stress and inhibits the growth of malignant cells.

Tea Polyphenols and Their Preventive Measures against Cancer: Current Trends and Directions

Cancer is exerting an immense strain on the population and health systems all over the world. Green tea because of its higher simple catechin content (up to 30% on dry weight basis) is greatly popular as an anti-cancer agent which is found to reduce the risks of cancer as well as a range of other diseases. In addition, several in vitro and in vivo studies have shown that green tea possesses copious health benefits like anti-diabetic, anti-obese, anti-inflammatory, neuro-protective, cardio-protective, etc. This review highlights the anti-carcinogenic effects of green tea catechins integrating the recent information to gain a clear concept. Special emphasis was given to the effectiveness of green tea polyphenols (GTP) in the prevention of cancer. Overall, green tea has been found to be effective to reduce the risks of breast cancer, ovarian cancer, liver cancer, colorectal cancer, skin cancer, prostate cancer, oral cancer, etc. However, sufficient information was not found to support that green tea consumption reduces the risk of lung cancer, esophageal cancer, or stomach cancer. The exciting data integrated into this article will increase interest in future researchers to garner more fruitful information on the relevant topics.

Pharmacologic inhibition of LAT1 predominantly suppresses transport of large neutral amino acids and downregulates global translation in cancer cells

L‐type amino acid transporter 1 (LAT1; SLC7A5), which preferentially transports large neutral amino acids, is highly upregulated in various cancers. LAT1 supplies cancer cells with amino acids as substrates for enhanced biosynthetic and bioenergetic reactions and stimulates signalling networks involved in the regulation of survival, growth and proliferation. LAT1 inhibitors show anti‐cancer effects and a representative compound, JPH203, is under clinical evaluation. However, pharmacological impacts of LAT1 inhibition on the cellular amino acid transport and the translational activity in cancer cells that are conceptually pivotal for its anti‐proliferative effect have not been elucidated yet. Here, we demonstrated that JPH203 drastically inhibits the transport of all the large neutral amino acids in pancreatic ductal adenocarcinoma cells. The inhibitory effects of JPH203 were observed even in competition with high concentrations of amino acids in a cell culture medium. The analyses of the nutrient‐sensing mTORC1 and GAAC pathways and the protein synthesis activity revealed that JPH203 downregulates the global translation. This study demonstrates a predominant contribution of LAT1 to the transport of large neutral amino acids in cancer cells and the suppression of protein synthesis by JPH203 supposed to underly its broad anti‐proliferative effects across various types of cancer cells.

Metal complexes of benzimidazole-derived as potential anti-cancer agents: synthesis, characterization, combined experimental and computational studies

In this study, a series of 14 Cu (II), Zn (II), Ni (II) and Ag (I) complexes containing bis-benzimidazole derivatives were successfully designed and synthesized from 2-(1H-benzimidazole-2-yl)-phenol derivatives and corresponding metal salt solutions. The compound structures were identified by FT-IR, ¹H-NMR, powder X-ray diffraction and ESI-MS analyses, and the presence of the metal in the complexes was confirmed by ultraviolet-visible spectroscopy and ICP optical emission spectrometry. Electronic structure calculations were also carried out to describe the detailed structures in addition to the electronic absorption spectra of the ligands. The cytotoxic activity of the complexes was evaluated against three human cancer cell lines: lung (A549), breast (MDA-MB-231) and prostate (PC3) cancer cells. All complexes inhibited anti-proliferative cancer cells better than free ligands, especially Zn (II) and Ag (I) complexes, which are most sensitive to MDA-MB-231 cells. In addition, showing the growth inhibition of three cancer cell lines with IC₅₀ < 10.4 µM, complexes C₁ , C₃ and C₁₄ could be considered potential multi-targeted anti-cancer agents.

Metal complexes of benzimidazole-derived as potential anti-cancer agents: synthesis, characterization, combined experimental and computational studies

In this study, a series of 14 Cu (II), Zn (II), Ni (II) and Ag (I) complexes containing bis-benzimidazole derivatives were successfully designed and synthesized from 2-(1H-benzimidazole-2-yl)-phenol derivatives and corresponding metal salt solutions. The compound structures were identified by FT-IR, ¹H-NMR, powder X-ray diffraction and ESI-MS analyses, and the presence of the metal in the complexes was confirmed by ultraviolet-visible spectroscopy and ICP optical emission spectrometry. Electronic structure calculations were also carried out to describe the detailed structures in addition to the electronic absorption spectra of the ligands. The cytotoxic activity of the complexes was evaluated against three human cancer cell lines: lung (A549), breast (MDA-MB-231) and prostate (PC3) cancer cells. All complexes inhibited anti-proliferative cancer cells better than free ligands, especially Zn (II) and Ag (I) complexes, which are most sensitive to MDA-MB-231 cells. In addition, showing the growth inhibition of three cancer cell lines with IC₅₀ < 10.4 µM, complexes C₁ , C₃ and C₁₄ could be considered potential multi-targeted anti-cancer agents.

Cannabis as a potential compound against various malignancies, legal aspects, advancement by exploiting nanotechnology and clinical trials

Various preclinical and clinical studies exhibited the potential of cannabis against various diseases, including cancer and related pain. Subsequently, many efforts have been made to establish and develop cannabis-related products and make them available as prescription products. Moreover, FDA has already approved some cannabis-related products, and more advancement in this aspect is still going on. However, the approved product of cannabis is in oral dosage form, which exerts various limitations to achieve maximum therapeutic effects. A considerable translation is on a hike to improve bioavailability, and ultimately, the therapeutic efficacy of cannabis by the employment of nanotechnology. Besides the well-known psychotropic effects of cannabis upon the use at high doses, literature has also shown the importance of cannabis and its constituents in minimising the lethality of cancer in the preclinical models. This review discusses the history of cannabis, its legal aspect, safety profile, the mechanism by which cannabis combats with cancer, and the advancement of clinical therapy by exploiting nanotechnology. A brief discussion related to the role of cannabinoid in various cancers has also been incorporated. Lastly, the information regarding completed and ongoing trials have also been elaborated.

Pseudomonas aeruginosa in Cancer Therapy: Current Knowledge, Challenges and Future Perspectives

Drug resistance, undesirable toxicity and lack of selectivity are the major challenges of conventional cancer therapies, which cause poor clinical outcomes and high mortality in many cancer patients. Development of alternative cancer therapeutics are highly required for the patients who are resistant to the conventional cancer therapies, including radiotherapy and chemotherapy. The success of a new cancer therapy depends on its high specificity to cancer cells and low toxicity to normal cells. Utilization of bacteria has emerged as a promising strategy for cancer treatment. Attenuated or genetically modified bacteria were used to inhibit tumor growth, modulate host immunity, or deliver anti-tumor agents. The bacteria-derived immunotoxins were capable of destructing tumors with high specificity. These bacteria-based strategies for cancer treatment have shown potent anti-tumor effects both in vivo and in vitro, and some of them have proceeded to clinical trials. Pseudomonas aeruginosa, a Gram-negative bacterial pathogen, is one of the common bacteria used in development of bacteria-based cancer therapy, particularly known for the Pseudomonas exotoxin A-based immunotoxins, which have shown remarkable anti-tumor efficacy and specificity. This review concisely summarizes the current knowledge regarding the utilization of P. aeruginosa in cancer treatment, and discusses the challenges and future perspectives of the P. aeruginosa-based therapeutic strategies.

Inhibition of Carbonic Anhydrase IX Promotes Apoptosis through Intracellular pH Level Alterations in Cervical Cancer Cells

Carbonic anhydrase IX (CAIX) is a hypoxia-related protein that plays a role in proliferation in solid tumours. However, how CAIX increases proliferation and metastasis in solid tumours is unclear. The objective of this study was to investigate how a synthetic CAIX inhibitor triggers apoptosis in the HeLa cell line. The intracellular effects of CAIX inhibition were determined with AO/EB, AnnexinV-PI, and γ-H2AX staining; measurements of intracellular pH (pHi), reactive oxygen species (ROS), and mitochondrial membrane potential (MMP); and analyses of cell cycle, apoptotic, and autophagic modulator gene expression (Bax, Bcl-2, caspase-3, caspase-8, caspase-9, caspase-12, Beclin, and LC3), caspase protein level (pro-caspase 3 and cleaved caspase-3, -8, -9), cleaved PARP activation, and CAIX protein level. Sulphonamide CAIX inhibitor E showed the lowest IC50 and the highest selectivity index in CAIX-positive HeLa cells. CAIX inhibition changed the morphology of HeLa cells and increased the ratio of apoptotic cells, dramatically disturbing the homeostasis of intracellular pHi, MMP and ROS levels. All these phenomena consequent to CA IX inhibition triggered apoptosis and autophagy in HeLa cells. Taken together, these results further endorse the previous findings that CAIX inhibitors represent an important therapeutic strategy, which is worth pursuing in different cancer types, considering that presently only one sulphonamide inhibitor, SLC-0111, has arrived in Phase Ib/II clinical trials as an antitumour/antimetastatic drug.

Canine Parvovirus and Its Non-Structural Gene 1 as Oncolytic Agents: Mechanism of Action and Induction of Anti-Tumor Immune Response

The exploration into the strategies for the prevention and treatment of cancer is far from complete. Apart from humans, cancer has gained considerable importance in animals because of increased awareness towards animal health and welfare. Current cancer treatment regimens are less specific towards tumor cells and end up harming normal healthy cells. Thus, a highly specific therapeutic strategy with minimal side effects is the need of the hour. Oncolytic viral gene therapy is one such specific approach to target cancer cells without affecting the normal cells of the body. Canine parvovirus (CPV) is an oncolytic virus that specifically targets and kills cancer cells by causing DNA damage, caspase activation, and mitochondrial damage. Non-structural gene 1 (NS1) of CPV, involved in viral DNA replication is a key mediator of cytotoxicity of CPV and can selectively cause tumor cell lysis. In this review, we discuss the oncolytic properties of Canine Parvovirus (CPV or CPV2), the structure of the NS1 protein, the mechanism of oncolytic action as well as role in inducing an antitumor immune response in different tumor models.

Enhancing Anti-Tumoral Potential of CD-NHF by Modulating PI3K/Akt Axis in U87 Ex Vivo Glioma Model

BACKGROUND

In the latest years, there has been an increased interest in nanomaterials that may provide promising novel approaches to disease diagnostics and therapeutics. Our previous results demonstrated that Carbon-dots prepared from N-hydroxyphthalimide (CD-NHF) exhibited anti-tumoral activity on several cancer cell lines such as MDA-MB-231, A375, A549, and RPMI8226, while U87 glioma tumor cells were unaffected. Gliomas represent one of the most common types of human primary brain tumors and are responsible for the majority of deaths. In the present in vitro study, we expand our previous investigation on CD-NHF in the U87 cell line by adding different drug combinations.

METHODS

Cell viability, migration, invasion, and immunofluorescent staining of key molecular pathways have been assessed after various treatments with CD-NHF and/or K252A and AKTVIII inhibitors in the U87 cell line.

RESULTS

Association of an inhibitor strongly potentiates the anti-tumoral properties of CD-NHF identified by significant impairment of migration, invasion, and expression levels of phosphorylated Akt, p70S6Kinase, or by decreasing expression levels of Bcl-2, IL-6, STAT3, and Slug.

CONCLUSIONS

Using simultaneously reduced doses of both CD-NHF and an inhibitor in order to reduce side effects, the viability and invasiveness of U87 glioma cells were significantly impaired.

Triumph against cancer: invading colorectal cancer with nanotechnology

INTRODUCTION

Recent statistics have reported colorectal cancer (CRC) as the second leading cause of cancer-associated deaths in the world. Early diagnosis of CRC may help to reduce the mortality and associated complications. However, the conventional diagnostic techniques often lead to misdiagnosis, fail to differentiate benign from malignant tissue or diagnose only at an advanced stage. For the treatment of CRC, surgery, chemotherapy, immunotherapy, and radiotherapy have been employed. However, the quality of living of the CRC patients is highly compromised after employing current therapeutic approaches owing to the toxicity issues and relapse.

AREA COVERED

This review accentuates the molecular mechanisms involved in the pathogenesis, stages of CRC, conventional approaches for diagnosis and therapy of CRC and the issues confronted thereby. It provides an outlook on the advantages of employing nanotechnology-based approaches for prevention, early diagnosis, and treatment of CRC.

EXPERT OPINION

Employing nanotechnology-based approaches has demonstrated promising outcomes in the prevention, diagnosis, and treatment of CRC. Nanotechnology-based approaches can surmount the major drawbacks of traditional diagnostic and therapeutic approaches. Nanotechnology bestows the advantage of early detection of CRC which helps to undertake instant steps for offering efficient therapy and reducing the mortality rates. For the treatment of CRC, nanocarriers offer the benefit of achieving controlled drug release, improved drug bioavailability, enhanced tumor targetability and reduced adverse effects.

Pistachio Green Hull Extract Induces Apoptosis through Multiple Signaling Pathways by Causing Oxidative Stress on Colon Cancer Cells

BACKGROUND

Pistachio is considered to be one of the fifty foods with the highest antioxidant effect. However, the anticancer effect mechanisms of this plant extracts are unknown.

OBJECTIVE

The aim of this study was to investigate the anticancer effect of different extracts from the green hull of pistachio.

METHODS

The cytotoxic effects of different solvent extracts on cancer and normal cells were examined by cell viability assay and flow cytometric analysis. The levels of the apoptotic gene and protein were investigated by Western Blot and ELISA, and qPCR. The intracellular free radical exchange was determined by oxidative and nitric oxide analyses. DNA damage level was measured by the 8-OHdG test. Phenolic and free fatty acid components were examined by LC-MS/MS and GC-MS, respectively.

RESULTS

It was determined that the n-hexane fraction showed a higher cytotoxic effect on cancer cells. Oxidative and cell cycle analyses indicated that the n-hexane fraction arrested cell cycle of HT-29 at the sub-G1 phase by increasing DNA damage through oxidative stress. In addition, gene expression analysis of the HT-29 treated with the n-hexane fraction indicated that apoptotic and autophagic gene expressions were significantly upregulated. LC-MS/MS analysis of the n-hexane fraction revealed the presence of 15 phenolic compounds, containing mainly gallic acid and catechin hydrate, and GC-MS analysis determined the presence of the following fatty acids: 9-octadecenoic acid, 9,12-octadecadienoic acid and hexadecenoic acid.

CONCLUSION

Based on these grounds, we suggest that the n-hexane fraction of pistachio green hull damages DNA, arrests the cell cycle at the G₁ subphase, and induces apoptosis through oxidative pathways in colon cancer.

The Multi-Level Mechanism of Action of a Pan-Ras Inhibitor Explains its Antiproliferative Activity on Cetuximab-Resistant Cancer Cells

Ras oncoproteins play a crucial role in the onset, maintenance, and progression of the most common and deadly human cancers. Despite extensive research efforts, only a few mutant-specific Ras inhibitors have been reported. We show that cmp4–previously identified as a water-soluble Ras inhibitor– targets multiple steps in the activation and downstream signaling of different Ras mutants and isoforms. Binding of this pan-Ras inhibitor to an extended Switch II pocket on HRas and KRas proteins induces a conformational change that down-regulates intrinsic and GEF-mediated nucleotide dissociation and exchange and effector binding. A mathematical model of the Ras activation cycle predicts that the inhibitor severely reduces the proliferation of different Ras-driven cancer cells, effectively cooperating with Cetuximab to reduce proliferation even of Cetuximab-resistant cancer cell lines. Experimental data confirm the model prediction, indicating that the pan-Ras inhibitor is an appropriate candidate for medicinal chemistry efforts tailored at improving its currently unsatisfactory affinity.

Clinical Review: Navitoclax as a Pro-Apoptotic and Anti-Fibrotic Agent

B-cell lymphoma 2 (BCL-2) family proteins primarily work as a programmed cell death regulator, whereby multiple interactions between them determine cell survival. This explains the two major classes of BCL-2 proteins which are anti-apoptotic and pro-apoptotic proteins. The anti-apoptotic proteins are attractive targets for BCL-2 family inhibitors, which result in the augmentation of the intrinsic apoptotic pathway. BCL-2 family inhibitors have been studied extensively for novel targeted therapies in various cancer types, fibrotic diseases, aging-related as well as autoimmune diseases. Navitoclax is one of them and it has been discovered to have a high affinity toward BCL-2 anti-apoptotic proteins, including BCL-2, BCL-W and B-cell lymphoma-extra-large. Navitoclax has been demonstrated as a single agent or in combination with other drugs to successfully ameliorate tumor progression and fibrosis development. To date, navitoclax has entered phase I and phase II clinical studies. Navitoclax alone potently treats small cell lung cancer and acute lymphocytic leukemia, whilst in combination therapy for solid tumors, it enhances the therapeutic effect of other chemotherapeutic agents. A low platelet count has always associated with single navitoclax treatments, though this effect is tolerable. Moreover, the efficacy of navitoclax is determined by the expression of several BCL-2 family members. Here, we elucidate the complex mechanisms of navitoclax as a pro-apoptotic agent, and review the early and current clinical studies of navitoclax alone as well as with other drugs. Additionally, some suggestions on the development of navitoclax clinical studies are presented in the future prospects section.

Potent Small-Molecule Inhibitors Targeting Acetylated Microtubules as Anticancer Agents Against Triple-Negative Breast Cancer

Microtubules are one of the major targets for anticancer drugs because of their role in cell proliferation and migration. However, as anticancer drugs targeting microtubules have side effects, including the death of normal cells, it is necessary to develop anticancer agents that can target microtubules by specifically acting on cancer cells only. In this study, we identified chemicals that can act as anticancer agents by specifically binding to acetylated microtubules, which are predominant in triple-negative breast cancer (TNBC). The chemical compounds disrupted acetylated microtubule lattices by interfering with microtubule access to alpha-tubulin acetyltransferase 1 (αTAT1), a major acetyltransferase of microtubules, resulting in the increased apoptotic cell death of MDA-MB-231 cells (a TNBC cell line) compared with other cells, such as MCF-10A and MCF-7, which lack microtubule acetylation. Moreover, mouse xenograft experiments showed that treatment with the chemical compounds markedly reduced tumor growth progression. Taken together, the newly identified chemical compounds can be selective for acetylated microtubules and act as potential therapeutic agents against microtubule acetylation enrichment in TNBC.

Structural (at 100 K) and DFT studies of 2'-nitro-flavone

The geometry of the title mol-ecule [systematic name: 2-(2-nitro-phen-yl)-4H-chromen-4-one], C15H9NO4, is determined by two dihedral angles formed by the mean plane of phenyl ring with the mean planes of chromone moiety and nitro group, being 50.73 (5) and 30.89 (7)°, respectively. The crystal packing is determined by π-π inter-actions and C-H⋯O contacts. The results of DFT calculations at the B3LYP/6-31G* level of theory provided an explanation of the unusually large dihedral angle between the chromone moiety and the phenyl group. The electrostatic potential map on the mol-ecular surface was calculated in order to determine the potential binding sites to receptors.

Synthesis of Ni0.5Co0.5-xCdxFe1.78Nd0.02O4 (x ≤ 0.25) nanofibers by using electrospinning technique induce anti-cancer and anti-bacterial activities

Here we report the electrospinning synthesis of Cd-substituted Ni-Co ferrite Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) nanofiber (NFs) with a very low concentration of Nd as a dopant. The structure and surface morphology of the Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) NFs were analyzed by X-ray powder pattern (XRD), transmission and scanning electron microscopes (TEM) along with Energy-dispersive X-ray (EDX). We have examined the biological applications of the Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) NFs on both cancerous cells and bacterial cells. We have found that Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) NFs produced inhibitory action on the human colorectal carcinoma cells (HEK-293) and also showed inhibitory action on the bacterial strains (S. aureus and E. coli) respectively. Finally, this is the first report on the synthesis of Cd- substituted Co-Ni ferrite nanofibers using electrospinning technique exhibiting anti-cancer and anti-bacterial activities.Communicated by Ramaswamy H. Sarma.

Advances in Histone Demethylase KDM3A as a Cancer Therapeutic Target

Lysine-specific histone demethylase 3 (KDM3) subfamily proteins are H3K9me2/me1 histone demethylases that promote gene expression. The KDM3 subfamily primarily consists of four proteins (KDM3A−D). All four proteins contain the catalytic Jumonji C domain (JmjC) at their C-termini, but whether KDM3C has demethylase activity is under debate. In addition, KDM3 proteins contain a zinc-finger domain for DNA binding and an LXXLL motif for interacting with nuclear receptors. Of the KDM3 proteins, KDM3A is especially deregulated or overexpressed in multiple cancers, making it a potential cancer therapeutic target. However, no KDM3A-selective inhibitors have been identified to date because of the lack of structural information. Uncovering the distinct physiological and pathological functions of KDM3A and their structure will give insight into the development of novel selective inhibitors. In this review, we focus on recent studies highlighting the oncogenic functions of KDM3A in cancer. We also discuss existing KDM3A-related inhibitors and review their potential as therapeutic agents for overcoming cancer.

Chronic Microangiopathy Due to DCR-MYC, a Myc-Targeted Short Interfering RNA

Thrombotic microangiopathy (TMA) is an emerging complication of oncologic therapy. Cancer-related causes of renal endothelial cell damage include cytotoxic chemotherapies, radiation given for myeloablation, and direct involvement of renal vasculature by tumor cells. Another class of therapeutic agents that has been implicated in TMA is the vascular endothelial growth factor (VEGF) pathway inhibitors, including the anti-VEGF monoclonal antibody bevacizumab and the VEGF receptor tyrosine kinase inhibitor sunitinib. These TMAs have been termed type II cancer drug-induced TMA and are distinguished from those associated with some cytotoxic chemotherapies (ie, type I) in that they are not dose dependent and patients are more likely to demonstrate some recovery of kidney function. Determination of the cause of TMA in oncologic patients often presents a significant challenge because patients frequently receive multiple chemotherapeutic agents simultaneously and clinicopathologic features often demonstrate substantial overlap, regardless of cause. We present a case of TMA with predominantly chronic features in a 70-year-old patient being treated for adenoid cystic carcinoma of the breast with a single agent, a short interfering RNA targeted against Myc (DCR-MYC).

The discovery and characterization of K-563, a novel inhibitor of the Keap1/Nrf2 pathway produced by Streptomyces sp

Keap1/Nrf2 pathway regulates the antioxidant stress response, detoxification response, and energy metabolism. Previous reports found that aberrant Keap1/Nrf2 pathway activation due to Kelch‐like ECH‐associated protein 1 (Keap1) mutations or Nuclear factor E2‐related factor 2 (Nrf2) mutations induced resistance of cancer cells to chemotherapy and accelerated cell growth via the supply of nutrients. Therefore, Keap1/Nrf2 pathway activation is associated with a poor prognosis in many cancers. These previous findings suggested that inhibition of Keap1/Nrf2 pathway could be a target for anti‐cancer therapies. To discover a small‐molecule Keap1/Nrf2 pathway inhibitor, we conducted high‐throughput screening in Keap1 mutant human lung cancer A549 cells using a transcriptional reporter assay. Through this screening, we identified the novel Keap1/Nrf2 pathway inhibitor K‐563, which was isolated from actinomycete Streptomyces sp. K‐563 suppressed the expression of Keap1/Nrf2 pathway downstream target genes or the downstream target protein, which induced suppression of GSH production, and activated reactive oxygen species production in A549 cells. K‐563 also inhibited the expression of downstream target genes in other Keap1‐ or Nrf2‐mutated cancer cells. Furthermore, K‐563 exerted anti‐proliferative activities in these mutated cancer cells. These in vitro analyses showed that K‐563 was able to inhibit cell growth in Keap1‐ or Nrf2‐mutated cancer cells by Keap1/Nrf2 pathway inhibition. K‐563 also exerted synergistic combinational effects with lung cancer chemotherapeutic agents. An in vivo study in mice xenotransplanted with A549 cells to further explore the therapeutic potential of K‐563 revealed that it also inhibited Keap1/Nrf2 pathway in lung cancer tumors. K‐563, a novel Keap1/Nrf2 pathway inhibitor, may be a lead compound for development as an anti‐cancer agent.

Anticancer agent ABT-737 possesses anti-atopic dermatitis activity via blockade of caspase-1 in atopic dermatitis in vitro and in vivo models

OBJECTIVE

Previous studies reported that depletion of Bcl-2 has a protective effect against allergic diseases. Furthermore, recently our study showed that anticancer drug has antiallergic inflammatory effect. An anticancer agent ABT-737 is an inhibitor of Bcl-2 and has an anti-inflammatory effect. However, the antiallergic inflammatory activity of ABT-737 is still unknown. Here, we aimed to explore the anti-atopic dermatitis (AD) activity and the mechanism of ABT-737 in AD models.

MATERIALS AND METHODS

HaCaT cells were used for in vitro experiments. To evaluate the effect of ABT-737 in vivo model, BalB/c mice were orally administered ABT-737 for 6 weeks in 2,4-dinitrofluorobenzene (DNFB)-induced AD-like murine model. Major assays were enzyme-linked immunosorbent assay, reverse transcription-PCR, caspase-1 assay, histamine assay, and H&E staining.

RESULTS

ABT-737 significantly decreased thymic stromal lymphopoietin (TSLP) secretion and caspase-1 activity in activated HaCaT cells. In DNFB-induced AD mice, oral administration of ABT-737 alleviated clinical severity and scratching behavior. ABT-737 decreased levels of AD-related biomarkers including IgE, histamine, TSLP, and inflammatory cytokines. In addition, ABT significantly reduced caspase-1 activity in skin lesions of AD mice.

DISCUSSION AND CONCLUSIONS

ABT-737 elicited an anti-AD activity via suppression of caspase-1 activation in AD in vitro and in vivo models. Therefore, this study provides important information regarding the use of anticancer drugs for controlling allergic inflammatory diseases.

Mitochondria-targeted metformins: anti-tumour and redox signalling mechanisms

Reports suggest that metformin exerts anti-cancer effects in diabetic individuals with pancreatic cancer. Thus, metformin is currently being repurposed as a potential drug in cancer treatment. Studies indicate that potent metformin analogues are required in cancer treatment because of the low bioavailability of metformin in humans at conventional antidiabetic doses. We proposed that improved mitochondrial targeting of metformin by attaching a positively charged lipophilic triphenylphosphonium group will result in a new class of mitochondria-targeted metformin analogues with significantly enhanced anti-tumour potential. Using this approach, we synthesized various mitochondria-targeted metformin analogues with different alkyl chain lengths. Results indicate that the antiproliferative effects increased with increasing alkyl chain lengths (100-fold to 1000-fold). The lead compound, mito-metformin₁₀, potently inhibited mitochondrial respiration through inhibition of complex I, stimulation of superoxide and hydrogen peroxide formation and activation of AMPK. When used in combination with ionizing radiation, mito-metformin₁₀ acted as a radiosensitizer of pancreatic cancer cells. Because of the 1000-fold-higher potency of mitochondria-targeted metformin₁₀, therapeutically effective plasma concentrations likely can be achieved in cancer patients.

Metformin and Anti-Cancer Therapeutics: Hopes for a More Enhanced Armamentarium Against Human Neoplasias?

Metformin, a natural product from Galega officinalis, is an oral drug, now in the forefront of the therapeutic management of type-2 diabetes mellitus. A series of clinical observations of the last decades, support that metformin may contribute to lowering the risk of cancer development in diabetic patients, and also to improvement of response-to-therapy and survival in individuals with certain types of malignancies. Moreover, several preclinical in vitro and in vivo data indicate that metformin indeed exerts anti-proliferative capacities upon tumor cells mediated through a variety of mechanisms. Interestingly, metformin has been shown to act in synergy with certain anti-cancer agents and also to overcome chemo- and/or radio-resistance of various types of tumors, providing a hopeful rationale for novel therapeutic strategies against cancer development and progression. However, this remains an issue of controversy, since significant contradictions exist among the available data. Limitations of preclinical studies and caveats of epidemiological works, together with significant variances among the several types of cancer and the fact that the mode of metformin's action is largely unknown, make longitudinal surveys urgently needed. Now, a plethora of large clinical trials are active worldwide, aiming at determining the effect of metformin in the prevention or prognosis of a variety of human cancers. If encouraging results arise, metformin will be an attractive candidate adjuvant in the management of human neoplasias, due to its safety, tolerability and low-cost, expected to mitigate adverse effects and no-response parameters of current anti-cancer therapeutics, thus improving the quality of life and survival of cancer patients.

RY-2f, an isoflavone analog, overcomes cisplatin resistance to inhibit ovarian tumorigenesis via targeting the PI3K/AKT/mTOR signaling pathway

Ovarian cancer remains the leading cause of death in gynecologic malignancies partially because of resistance to chemotherapy. In the present study, we show that RY-2f, a chemically synthesized isoflavone analog, inhibited ovarian cancer cell proliferation, blocked cell cycle in G2/M phase and induced cellular apoptosis through up-regulation of p21, cyclin B1, Bax, Bad and cleaved-PARP, and suppression of cyclin A, CDK2 and Bcl-2. We also show that RY-2f could increase the chemotherapeutic efficacy of cisplatin as tested by cell proliferation and colony formation assays, indicating a synergistic effect of RY-2f and cisplatin. Mechanistic study revealed that RY-2f exerted the anti-tumor activities mainly through suppression of the PI3K/AKT/mTOR signaling. Finally, in vivo studies showed that RY-2f blocked the A2780-induced xenograft tumor growth without detectable toxicity in the animals at the therapeutic doses, and whereas RY-2f re-sensitized the cisplatin resistant cell line A2780/CDDP induced xenograft tumor to cisplatin treatment. Thus, RY-2f may be developed as a potential therapeutic agent to treat ovarian cancer.

Selective synthesis of either enantiomer of an anti-breast cancer agent via a common enantioenriched intermediate

A stereoselective synthesis of a bioactive triarylmethane is described. Key to the synthesis is a nickel-catalyzed Suzuki-Miyaura coupling which proceeds with retention at the benzylic center. This method is complementary to our previously reported nickel-catalyzed Kumada coupling which proceeds with inversion. Together, the two methods allow for efficient access to either enantiomer of biologically relevant triarylmethanes from a common enantioenriched intermediate.

Synthesis of chromonylthiazolidines and their cytotoxicity to human cancer cell lines

Nine new chromonylthiazolidine derivatives were successfully semi-synthesized from paeonol. All of the compounds, including starting materials, the intermediate compound and products, were evaluated for their cytotoxic effects toward eight human cancer cell lines. The synthesized chromonylthiazolidines displayed weak cytotoxic effects against the tested cancer cell lines, but selective cytotoxic effects were observed. Compounds 3a and 3b showed the most selective cytotoxic effects against human epidermoid carcinoma (IC50 44.1 ± 3.6 μg/mL) and breast cancer (IC50 32.8 ± 1.4 μg/mL) cell lines, respectively. The results suggest that chromoylthiazolidines are potential low-cost, and selective anticancer agents.

Comparison of crystal structures of 4-(benzo[b]thio-phen-2-yl)-5-(3,4,5-tri-meth-oxy-phen-yl)-2H-1,2,3-triazole and 4-(benzo[b]thio-phen-2-yl)-2-methyl-5-(3,4,5-tri-meth-oxy-phen-yl)-2H-1,2,3-triazole

In the crystal structure of (I), the mol­ecules are linked into chains by N—H⋯O hydrogen bonds with (5) ring motifs. After the N-methyl­ation of structure (I), no hydrogen-bonding inter­actions were observed for structure (II).

The title compound, C₁₉H₁₇N₃O₃S (I), was prepared by a [3 + 2]cyclo­addition azide condensation reaction using sodium azide and l-proline as a Lewis base catalyst. N-Methyl­ation of compound (I) using CH₃I gave compound (II), C₂₀H₁₉N₃O₃S. The benzo­thio­phene ring systems in (I) and (II) are almost planar, with r.m.s deviations from the mean plane = 0.0205 (14) in (I) and 0.016 (2) Å in (II). In (I) and (II), the triazole rings make dihedral angles of 32.68 (5) and 10.43 (8)°, respectively, with the mean planes of the benzo­thio­phene ring systems. The trimeth­oxy phenyl rings make dihedral angles with the benzo­thio­phene rings of 38.48 (4) in (I) and 60.43 (5)° in (II). In the crystal of (I), the mol­ecules are linked into chains by N—H⋯O hydrogen bonds with R²₁(5) ring motifs. After the N-methyl­ation of structure (I), no hydrogen-bonding inter­actions were observed for structure (II). The crystal structure of (II) has a minor component of disorder that corresponds to a 180° flip of the benzo­thio­phene ring system [occupancy ratio 0.9363 (14):0.0637 (14)].

Getting into the colon: approaches to target colorectal cancer

Colorectal cancer (CRC) is the third most common cancer in the world and the second most common cause of cancer related deaths. Conventional treatment of CRC is comprised of drug (chemotherapeutic agents) administration by parenteral route, which delivers the drug to both normal as well as cancerous tissues, thus leading to numerous undesirable effects. Enormous research is going on worldwide for designing an alternative route of administration, among which oral colon-targeted drug delivery systems have gained immense attention amongst scientific community. Direct delivery of drugs at the site of action leads to an increase in the availability of drugs at the targeted region. This causes a reduction in the amount of drug required to exert same therapeutic effect, thus reducing the incidents of adverse effects. Various maneuvers (pH-dependent, time-dependent and microflora-activated systems) have been attempted by researchers for targeting drugs successfully to the colonic region by circumventing the upper part of gastrointestinal tract. This Editorial article aims to put forth an overview of the formulation technologies that have been developed for attaining colon specific drug delivery for the treatment of CRC.

A predictive biomarker for altered 5-fluorouracil pharmacokinetics following repeated administration in a rat model of colorectal cancer

The relationship between the plasma ratio of dihydrouracil/uracil (UH2/Ura) and hepatic dihydropyrimidine dehydrogenase (DPD) activity after repeated 5-fluorouracil (5-FU) treatment in rats with colorectal cancer (CRC) was investigated. Repeated intravenous 5-FU bolus injections resulted in a significant decrease in the total clearance (CLtot ) and an increased area under the curve (AUC0-∞ ) in CRC rats. Furthermore, the hepatic DPD levels and the plasma ratio of UH2/Ura decreased significantly and lost their circadian rhythms in CRC rats treated repeatedly with 5-FU, although significant circadian variation in the two parameters was observed in the control CRC rats. Moreover, a significant correlation was found between the plasma ratio of UH2/Ura and hepatic DPD activity in CRC rats untreated and treated with single or repeated 5-FU administration (r(2)  = 0.865, p < 0.01). The ratio of UH2/Ura in plasma could be a predictive biomarker of the suppression of hepatic DPD levels during repeated 5-FU-based treatment. Furthermore, by plotting the observed pharmacokinetic parameters of 5-FU against hepatic DPD activity levels predicted by the ratio of UH2/Ura in plasma, AUC0-∞ , CLtot and half-life (t1/2 ) were closely linked to predicted hepatic DPD activity levels. These observations suggest that the factor that significantly influences the AUC0-∞ , CLtot and t1/2 of 5-FU after single or repeated administration of 5-FU is the hepatic DPD activity and it could be assessed by the ratio of UH2/Ura in plasma.