Repurposing mechanistic insight of PDE-5 inhibitor in cancer chemoprevention through mitochondrial-oxidative stress intervention and blockade of DuCLOX signalling

Novel furan chalcone modulates PHD-2 induction to impart antineoplastic effect in mammary gland carcinoma

Normoxic inactivation of prolyl hydroxylase-2 (PHD-2) in tumour microenvironment paves the way for cancer cells to thrive under the influence of HIF-1α and NF-κB. Henceforth, the present study is aimed to identify small molecule activators of PHD-2. A virtual screening was conducted on a library consisting of 265,242 chemical compounds, with the objective of identifying molecules that exhibit structural similarities to the furan chalcone scaffold. Further, PHD-2 activation potential of screened compound was determined using in vitro 2-oxoglutarate assay. The cytotoxic activity and apoptotic potential of screened compound was determined using various staining techniques, including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, 4',6-diamidino-2-phenylindole (DAPI), 1,1',3,3'-tetraethylbenzimi-dazolylcarbocyanine iodide (JC-1), and acridine orange/ethidium bromide (AO/EB), against MCF-7 cells. 7,12-Dimethylbenz[a]anthracene (DMBA) model of mammary gland cancer was used to study the in vivo antineoplastic efficacy of screened compound. [(E)-1-(4-fluorophenyl)-3-(furan-2-yl) prop-2-en-1-one] (BBAP-7) was screened and validated as a PHD-2 activator by an in vitro 2-oxo-glutarate assay. The IC50 of BBAP-7 on MCF-7 cells is 18.84 µM. AO/EB and DAPI staining showed nuclear fragmentation, blebbing and condensation in MCF-7 cells following BBAP-7 treatment. The red-to-green intensity ratio of JC-1 stained MCF-7 cells decreased after BBAP-7 treatment, indicating mitochondrial-mediated apoptosis. DMBA caused mammary gland dysplasia, duct hyperplasia and ductal carcinoma in situ. Carmine staining, histopathology, and scanning electron microscopy demonstrated that BBAP-7, alone or with tirapazamine, restored mammary gland surface morphology and structural integrity. Additionally, BBAP-7 therapy significantly reduced oxidative stress and glycolysis. The findings reveal that BBAP-7 activates PHD-2, making it a promising anticancer drug.

Mechanistic crosstalk of extracellular calcium-mediated regulation of maturation and plasticity in human monocytes

Innate immune cells play a pivotal role in controlling tissue repair and rejection after biomaterial implantation. Calcium supplementation regulates cellular responses and alter the pathophysiology of various diseases. A series of macrophage activations through differential plasticity has been observed after cell-to-material interactions. We investigated the role of calcium supplementation in controlling macrophage phenotypes in pro-inflammatory and pre-reparative states. Oxidative defence and mitochondria involvement in cellular plasticity and the sequential M0 to M1 and M1 to M2 transitions were observed after calcium supplementation. This study describes the molecular mechanism of reactive oxygen species and drives the interconnected cellular plasticity of macrophages in the presence of calcium. Gene expression, and immunostaining, revealed a relationship between MHC class II maturation and cellular plasticity. This study elucidated the role of controlled calcium supplementation under various conditions. These findings underscore the molecular mechanism of calcium-mediated immune induction and its favourable use in different calcium-containing biomaterials., essential for tissue regeneration.

Macrophage Polarization Profiling on Native and Regenerated Silk Biomaterials

We investigated the plasticity and polarization of THP-1 cells on native and regenerated silk-based biomaterials to address the basic paradigm of immune response. Here, we report redox kinetics, adhesion morphology, and nitric oxide release patterns to identify specific subtypes of macrophages at different time points. Water-annealed silk film and native fibrous braids from Bombyx mori silkworms showed higher anti-inflammatory cytokine profiles or M2 subtypes (as evidenced by the enhanced expression of interleukin-10, interleukin-13, and interleukin-4). Ethanol-treated Bombyx mori silk films and Antheraea mylitta braids exhibited higher levels of pro-inflammatory cytokines or the M1 subtype (as evidenced by enhanced expression of interleukin-1, interleukin-6, interleukin-8, interferon-γ, TNF-α, and GM-CSF) in contact with healthy THP monocytes for 14 days; such a long study is unprecedented. Cytokine microarray analysis revealed the transition (M0-M1, M1-M2), plasticity, and stable phenotype of THP-1 cells in a variable stage in contact with different physicochemical properties of silk-based biomaterials. The detailed immunogenicity in the context of the physicochemical properties of native and regenerative silk-based biomaterials will enable us to accurately predict the possibility of a pro-/anti-inflammatory response. It will helps to predict the in vivo reprogramming and avoid fibrosis formation to enhance their clinical translational potential.

How do phosphodiesterase-5 inhibitors affect cancer? A focus on glioblastoma multiforme

Since the discovery of phosphodiesterase-5 (PDE5) enzyme overexpression in the central nervous system (CNS) malignancies, investigations have explored the potential capacity of current PDE5 inhibitor drugs for repositioning in the treatment of brain tumors, notably glioblastoma multiforme (GBM). It has now been recognized that these drugs increase brain tumors permeability and enhance standard chemotherapeutics effectiveness. More importantly, studies have highlighted the promising antitumor functions of PDE5 inhibitors, e.g., triggering apoptosis, suppressing tumor cell growth and invasion, and reversing tumor microenvironment (TME) immunosuppression in the brain. However, contradictory reports have suggested a pro-oncogenic role for neuronal cyclic guanosine monophosphate (cGMP), indicating the beneficial function of PDE5 in the brain of GBM patients. Unfortunately, due to the inconsistent preclinical findings, only a few clinical trials are evaluating the therapeutic value of PDE5 inhibitors in GBM treatment. Accordingly, additional studies should be conducted to shed light on the precise effect of PDE5 inhibitors in GBM biology regarding the existing molecular heterogeneities among individuals. Here, we highlighted and discussed the previously investigated mechanisms underlying the impacts of PDE5 inhibitors in cancers, focusing on GBM to provide an overview of current knowledge necessary for future studies.

Repurposing Combination Therapy of Voacamine With Vincristine for Downregulation of Hypoxia-Inducible Factor-1α/Fatty Acid Synthase Co-axis and Prolyl Hydroxylase-2 Activation in ER+ Mammary Neoplasia

The current study investigated the role of combination therapy with voacamine and vincristine in preventing mammary gland carcinoma through prolyl hydroxylase-2 activation. Prolyl hydroxylase-2 activation leads to the downregulation of hypoxia-inducible factor-1α and fatty acid synthase. Overexpression of hypoxia-inducible factor-1α and fatty acid synthase has been previously reported in solid tumors of the mammary gland. After screening a battery of natural compounds similar to vincristine, voacamine was selected as a possible prolyl hydroxylase-2 activator, and its activity was evaluated using a 7,12-dimethylbenz[a]anthracene-induced rat model. The combination therapy was evaluated for cardiac toxicity using a hemodynamic profile. Angiogenic markers were evaluated by carmine staining. Monotherapy and combination therapy were also evaluated for liver and kidney toxicity using hematoxylin and eosin staining. The antioxidant potential was delineated using oxidative stress markers. The serum metabolomic profile was studied using NMR spectroscopy, and the disruption of fatty acids was evaluated using gas chromatography. Western blotting of proteins involved in hypoxic pathways was performed to decipher the action of therapy at the molecular level. Immunoblotting analysis validated that combination therapy has potential toss with prolyl hydroxylase-2 activity and thus initiates proteolytic degradation of hypoxia-inducible factor-1α and its consequent effects. Combination therapy also stimulated programmed cell death (apoptosis) in rapidly dividing cancer cells. The present study explored the role of voacamine inactivation of prolyl hydroxylase-2, which can decrease the overexpression of hypoxia-inducible factor-1α and fatty acid synthase in mammary gland carcinoma cells.

Effect of Voacamine upon inhibition of hypoxia induced fatty acid synthesis in a rat model of methyln-nitrosourea induced mammary gland carcinoma

BACKGROUND

In the present study, fatty acid synthesis is targeted to combat mammary gland carcinoma by activating prolyl hydroxylase-2 with Voacamine alone and in combination with Tamoxifen. It was hypothesized that the activation of prolyl hydroxylase-2 would inhibit the hypoxia-induced fatty acid synthesis and mammary gland carcinoma. Mammary gland carcinoma was induced with a single dose administration of N-methyl-N-nitrosourea (50 mg/kg,i.p.) and treatment with Voacamine and Tamoxifen 15 days after carcinogen administration.

RESULTS

At the end of the study, hemodynamic profiling of animals was recorded to assess the cardiotoxic potential of the drug. Blood serum was separated and subjected to nuclear magnetic resonance spectroscopy. Carmine staining and histopathology of mammary gland tissue were performed to evaluate the anti-angiogenic potential of the drug. The antioxidant potential of the drug was measured with antioxidant markers. Western blotting was performed to study the effect of the drug at the molecular level.

CONCLUSION

Results of the study have shown that Voacamine treatment stopped further decrease in body weight of experimental animals. The hemodynamic study evidenced that Voacamine at a low dose is safe in cardiac patients. Microscopic evaluation of mammary gland tissue documented the anti-angiogenic potential of Voacamine and Tamoxifen therapy. Perturbed serum metabolites were also restored to normal along with antioxidant markers. Immunoblotting of mammary gland tissue also depicted restoration of proteins of the hypoxic and fatty acid pathway. Conclusively, Voacamine and its combination with Tamoxifen activated prolyl hydroxylase-2 to combat mammary gland carcinoma.

Evaluation of antidiabetic and hypolipidemic activity of Barleria cristata Linn. leaves in alloxan-induced diabetic rats

The present study was undertaken to evaluate the antidiabetic and hypolipidemic action of leaf extract of Barleria cristata Linn in rats. Diabetes was induced in the rats by a single intraperitoneal (IP) injection of alloxan (150 mg/kg) and randomly divided into 7 groups. Animals were treated with low (250 mg/kg) and high (500 mg/kg) doses of ethyl acetate leaf extract (EALE) and hydro-alcoholic leaf extract (HALE) up to 21 days. The body weight and blood glucose level (BGL) were measured on weekly basis. The rats were killed under mild ether anesthesia on 21st day, blood and the vital organ were collected to estimate biochemical parameters and to study histopathological changes. A single-dose administration of alloxan induced hyperglycemia in all the groups. A regular increase in BGL was observed in toxic control groups when compared with the normal control. Daily oral administration of rats with extracts (HALE and EALE) and standard drug (Glimepiride, 5 mg/kg), reduced elevated BGL significantly (p < 0.001), and body weight was regained in diabetic rats. The extract treatment also improved the normal functioning of the liver and kidneys as evidenced by the restoration of the biochemical profile. The study revealed that B. cristata possesses promising antidiabetic and hypolipidemic activity.

Drug combination and repurposing for cancer therapy: the example of breast cancer

Cancer is a set of extremely complex diseases, which are increasingly prominent today, as it affects and kills millions of people worldwide, being the subject of intense study both in its pathophysiology and therapy. Especially in women, breast cancer is still a cancer with a high incidence and mortality. Even though mortality rates for this type of cancer have declined in recent years, it remains challenging at the treatment level, especially the metastatic type. Due to all the impact on health, cancer therapy is the subject of costly and intense research. To enrich this therapy, as well as decrease its underlying high associated costs, drug repurposing and drug combinations are strategies that have been increasingly studied and addressed. As the name implies, drug repurposing presupposes giving new purposes to agents which, in this case, are approved for the therapy of other diseases (for example, cardiovascular or metabolic diseases), but are not approved for cancer therapy. Therefore, a better knowledge of these therapeutic modalities for breast cancer therapy is crucial for improved therapy. In this particular review, we will discuss some relevant aspects of cancer and, particularly, breast cancer and its therapy. Also, drug combination and repurposing will be highlighted, together with relevant examples. Despite some limitations that need to be overcome, these methodologies are extremely important and advantageous in combating several current problems of cancer therapy, namely in terms of costs and resistance to current therapeutic modalities. These approaches will be explored with a special focus on breast cancer.

Fabrication of Imatinib Mesylate-Loaded Lactoferrin-Modified PEGylated Liquid Crystalline Nanoparticles for Mitochondrial-Dependent Apoptosis in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a major cause of concern as it has substantial morbidity associated with it. Previous reports have ascertained the antiproliferative activity of imatinib mesylate (IMS) against diverse types of carcinomas, but limited bioavailability has also been reported. The present study envisaged optimized IMS-loaded lactoferrin (LF)-modified PEGylated liquid crystalline nanoparticles (IMS-LF-LCNPs) for effective therapy of IMS to HCC via asialoglycoprotein receptor (ASGPR) targeting. Results displayed that IMS-LF-LCNPs presented an optimum particle size of 120.40 ± 2.75 nm, a zeta potential of +12.5 ± 0.23 mV, and 73.94 ± 2.69% release. High-resolution transmission electron microscopy and atomic force microscopy were used to confirm the surface architecture of IMS-LF-LCNPs. The results of cytotoxicity and 4,6-diamidino-2-phenylindole revealed that IMS-LF-LCNPs had the highest growth inhibition and significant apoptotic effects. Pharmacokinetics and biodistribution studies showed that IMS-LF-LCNPs have superior pharmacokinetic performance and targeted delivery compared to IMS-LCNPs and plain IMS, which was attributed to the targeting action of LF that targets the ASGPR in hepatic cells. Next, our in vivo experiment established that the HCC environment existed due to suppression of BAX, cyt c, BAD, e-NOS, and caspase (3 and 9) genes, which thus owed upstream expression of Bcl-xl, iNOS, and Bcl-2 genes. The excellent therapeutic potential of IMS-LF-LCNPs began the significant stimulation of caspase-mediated apoptotic signals accountable for its anti-HCC prospect. ¹H nuclear magnetic resonance (serum) metabolomics revealed that IMS-LF-LCNPs are capable of regulating the disturbed levels of metabolites linked to HCC triggered through N-nitrosodiethylamine. Therefore, IMS-LF-LCNPs are a potentially effective formulation against HCC.

Calliandra portoricensis ameliorates ovarian and uterine oxido-inflammatory responses in N-methyl-N-nitrosourea and benzo[a]pyrene-treated rats

IMPACT STATEMENT

Infertility resulting from reproductive impairment is traumatic in families. Exposure to chemicals may play insidious roles not easily connected to infertility. We examined benzo[a]pyrene (BaP), and N-methyl nitrosourea (NMU)-induced ovarian and uterine toxicity and the role of Calliandra portoricensis in mitigating toxicity. In a bid to illuminate folk medical claims cloaked in mystery, unearthing lost knowledge, advance natural chemopreventive agents, and report new evidence lacking in the literature attributed to CP. Although CP is known to exhibit anticonvulsant, antidiarrheal, antipyretic, antirheumatic, and analgesic effects in humans, its possible roles for mitigating toxicity stemming from inadvertent chemical exposures are reported here. Our findings affirm and further show that CP abates toxic response incumbent on oxidative damage and inflammatory responses associated with NMU and BaP exposure. Development of phytochemical derived from CP may serve as a potential natural therapy against chemical toxicities in individuals inadvertently exposed, and promote human health and reproductive satiety.

Chemoprophylactic activity of nitazoxanide in experimental model of mammary gland carcinoma in rats

The current study focuses on the evaluation of the chemoprophylactic activity of nitazoxanide against the mammary gland carcinoma in experimental rats. The experimental protocol involves total 50 female Wistar albino rats of body weight 120-150 g, which were randomly categorized into five groups; Normal control (1% w/v carboxymethyl cellulose, p.o.); Toxic control (N-methyl-N-nitrosourea, MNU, 47 mg/kg i.v.); Standard (MNU, 47 mg/kg i.v. + tamoxifen, 1 mg/kg p.o.); Treatment 1 (MNU, 47 mg/kg i.v. + NTZ low-dose, 25 mg/kg p.o.); and Treatment 2 (MNU, 47 mg/kg, i.v. + NTZ high-dose, 50 mg/kg p.o.). The mammary gland carcinoma was induced by a single tail vein intravenous injection of MNU at a 47 mg/kg dose. Seven days after MNU administration, daily dosing of nitazoxanide and tamoxifen was initiated till 110th day in respective groups. The MNU toxicity was apparent with the altered electrocardiogram and heart rate variability, increased number of alveolar bud count, differentiation score, and upregulated antioxidant parameters. Nitazoxanide treatment restored the histological architecture in rats along with the reduction of alveolar buds and downregulation of oxidative stress markers as well as inflammatory markers. Therefore, nitazoxanide can be utilized as a potential chemoprophylactic agent against mammary gland carcinoma induced by MNU.

Mitochondrial apoptosis and curtailment of hypoxia-inducible factor-1α/fatty acid synthase: A dual edge perspective of gamma linolenic acid in ER+ mammary gland cancer

Gamma linolenic acid is a polyunsaturated fatty acid having selective anti-tumour properties with negligible systemic toxicity. In the present study, the anti-cancer potential of gamma linolenic acid and its effects on mitochondrial as well as hypoxia-associated marker was evaluated. The effect of gamma linolenic acid was scrutinised against ER + MCF-7 cells by using fluorescence microscopy, JC-1 staining, dot plot assay and cell cycle analysis. The in vitro results were also confirmed using carcinogen (n-methyl-n-nitrosourea) induced in vivo model. The early and late apoptotic signals in the conjugation with mitochondrial depolarisation were found once scrutinised through mitochondrial membrane potential and life death staining after gamma linolenic acid treatment. Gamma linolenic acid arrested the cell cycle in G0/G1 phase with the majority of cell populations in the early apoptotic stage. The translocation of phosphatidylserine was studied through annexin-V FITC dot plot assay. The markers of cellular proliferation (decreased alveolar bud count, histopathological architecture restoration and loss of tumour micro-vessels) were diminished after gamma linolenic acid treatment. Gamma linolenic acid ameliorates the biological effects of n-methyl-n-nitrosourea persuading the mitochondrial mediated death pathway and impeding the hypoxic microenvironment to make a halt in palmitic acid synthesis. SIGNIFICANCE: The present study elaborates the effect of gamma linolenic acid on mammary gland cancer by following mitochondrial-mediated death apoptosis pathway. Gamma linolenic acid also inhibits cell-wall synthesis by the curtailment of HIF-1α and FASN level in mammary gland cancer.