Effects of psoralens as anti-tumoral agents in breast cancer cells

Natural linear coumarin-heterocyclic conjugates: A review of their roles in phytotherapy

Heterocycle conjugates provide a fresh investigative scope to find novel molecules with enhanced phytotherapeutic characteristics. Coumarin-based products are widely used in the synthesis of several compounds with biological and medicinal properties since they are naturally occurring heterocycles with a broad dispersion. The investigation of coumarin-based phytochemicals with annulated heterocyclic rings is a promising approach to discovering novel conjugates with significant phytotherapeutic attributes. Due to the applicable coumarin extraction processes, a range of linear coumarin-heterocyclic conjugates were isolated from different natural resources and exhibited remarkable therapeutic efficacy. This review highlights the phytotherapeutic potential and origins of various natural linear coumarin-heterocyclic conjugates. We searched several databases, including Science Direct, Web of Science, Springer, Google Scholar, and PubMed. After sieving, we ultimately identified and included 118 pertinent studies published between 2000 and the middle of 2023. This will inspire medicinal chemists with extremely insightful ideas for designing and synthesizing therapeutically active lead compounds in the future that are built on the pharmacophores of coumarin-heterocyclic conjugates and have significant therapeutic attributes.

Furanocoumarins as Enhancers of Antitumor Potential of Sorafenib and LY294002 toward Human Glioma Cells In Vitro

Furanocoumarins are naturally occurring compounds in the plant world, characterized by low molecular weight, simple chemical structure, and high solubility in most organic solvents. Additionally, they have a broad spectrum of activity, and their properties depend on the location and type of attached substituents. Therefore, the aim of our study was to investigate the anticancer activity of furanocoumarins (imperatorin, isoimperatorin, bergapten, and xanthotoxin) in relation to human glioblastoma multiforme (T98G) and anaplastic astrocytoma (MOGGCCM) cell lines. The tested compounds were used for the first time in combination with LY294002 (PI3K inhibitor) and sorafenib (Raf inhibitor). Apoptosis, autophagy, and necrosis were identified microscopically after straining with Hoechst 33342, acridine orange, and propidium iodide, respectively. The levels of caspase 3 and Beclin 1 were estimated by immunoblotting and for the blocking of Raf and PI3K kinases, the transfection with specific siRNA was used. The scratch test was used to assess the migration potential of glioma cells. Our studies showed that the anticancer activity of furanocoumarins strictly depended on the presence, type, and location of substituents. The obtained results suggest that achieving higher pro-apoptotic activity is determined by the presence of an isoprenyl moiety at the C8 position of the coumarin skeleton. In both anaplastic astrocytoma and glioblastoma, imperatorin was the most effective in induction apoptosis. Furthermore, the usage of imperatorin, alone and in combination with sorafenib or LY294002, decreased the migratory potential of MOGGCCM and T98G cells.

Rapid solid-liquid dynamic extraction of Cachrys pungens Jan ex Guss. aerial parts: influence on the photobiological and antioxidant properties

Cachrys pungens Jan ex Guss. (Apiaceae) is a perennial plant native to Italy and Northwestern Africa. This species is known for its content in furanocoumarins, and the methanolic extract obtained with maceration previously demonstrated significant phototoxicity on 375 melanoma cells. Here, in order to better explain the biological effects, the apoptotic responses on melanoma cancer cell line were verified. The aerial parts were extracted with methanol through an innovative solid-liquid extraction technology, the Naviglio extractor®, and the raw extract was tested for its photobiological properties on human melanoma C32 cells irradiated with UVA light. The in vitro antioxidant potential was assessed as well. The sample exerted a concentration-dependent photocytotoxic activity (IC50 value = 3.00 ± 0.16 µg/mL). In line with these evidences, in C32-treated cells subjected to UV irradiation, further data have reported an up-regulation of p53 and PARP, both proteins involved in apoptotic response and DNA repair.

Novel psoralen derivatives as anti-breast cancer agents and their light-activated cytotoxicity against HER2 positive breast cancer cells

Psoralen derivatives are well known for their unique phototoxicity and also exhibits promising anti-breast cancer activity both in the presence and the absence of UVA irradiation. However, the structure–activity relationship on this scaffold remains lacking. Herein, a series of psoralen derivatives with various C-5 substituents were synthesized and evaluated for their in vitro dark and light-activated cytotoxicity against three breast cancer cell lines: MDA-MB-231, T47-D, and SK-BR-3. The type of substituents dramatically impacted the activity, with the 4-bromobenzyl amide derivative (3c) exhibiting the highest dark cytotoxicity against T47-D (IC₅₀ = 10.14 µM), with the activity comparable to those of the reference drugs (doxorubicin, 1.46 µM; tamoxifen citrate, 20.86 µM; lapatinib 9.78 µM). On the other hand, the furanylamide 3g exhibits the highest phototoxicity against SK-BR-3 cells with the IC₅₀ of 2.71 µM, which is almost tenfold increase compared to the parent compound, methoxsalen. Moreover, these derivatives showed exceptional selectivity towards HER2+ (SK-BR-3) over the HER2− (MDA-MB-231) breast cancer cell lines, which correlates well with the results from the molecular docking study, revealing that 3g formed favorable interactions within the active site of the HER2. Additionally, the cell morphology of SK-BR-3 cells suggested that the significant phototoxicity was related to induction of cell apoptosis. Most of the synthesized psoralen derivatives possess acceptable physicochemical properties and are suitable for being further developed as a novel anti-breast cancer agent in the future.

Protective Effect of Bergapten against Human Erythrocyte Hemolysis and Protein Denaturation In Vitro

Bergapten, a furocoumarin found in many medicinal plants, is used for the management of various conditions. The present in vitro study evaluated the ability of bergapten to prevent human erythrocyte hemolysis and protein denaturation. Bergapten administered at 10, 30, and 100 μg/ml exhibited a significant concentration-dependent protection on the erythrocyte membrane exposed to hypotonicity and heat-induced hemolysis. The concentration at which bergapten inhibited 50% of the cells from hemolysis (IC₅₀) was determined on a dose-response curve, plotted as logarithmic (concentration) against percentage inhibition, keeping the hemolysis produced within the control group at 100%. Bergapten treatment produced an IC₅₀ value of 7.71 ± 0.27 μg/ml and 4.23 ± 0.42 μg/ml for hypotonicity and heat-induced hemolysis, respectively. Diclofenac sodium at similar concentrations produced an IC₅₀ value of 12.22 ± 0.30 μg/ml and 9.44 ± 0.23 μg/ml in the hypotonicity and heat-induced hemolysis, respectively. The ability of bergapten to inhibit protein denaturation was studied as part of an investigation on its mechanism of action. The results showed a significant concentration-dependent reduction in protein denaturation. When administered at 10, 30, and 100 μg/ml, bergapten produced a concentration-dependent reduction in albumin denaturation. Bergapten inhibited protein denaturation with IC₅₀ values of 5.34 ± 0.30 μg/ml and 12.18 ± 0.20 μg/ml in the heat-treated egg albumin and bovine serum albumin denaturation experiments, respectively. Diclofenac sodium (10, 30, and 100 μg/ml) exhibited a similar protection against heat-treated egg albumin and bovine serum albumin denaturation experiments with IC₅₀ values of 8.93 ± 0.17 μg/ml and 12.72 ± 0.11 μg/ml, respectively. Taken together, data from this study show that the pharmacological properties of bergapten may in part be related to its membrane-stabilizing and antidenaturation properties.

Migration of Excitation Energy in Furocoumarins

The migration of excitation energy of a number of psoralen compounds has been studied. For this, the methods of induced absorption spectroscopy, stationary electron spectroscopy, fluorescence and phosphorescence, as well as quantum chemistry were used. A comparative photostability of psoralen was achieved by exposure to a XeCl excilamp irradiation (emission wavelength λ_em = 308 nm) with parameters Δλ = 5-10 nm, W_peak = 18 mW/cm², p = 8.1 J/cm³, f = 200 kHz, pulse duration 1 μs. It was found that the singlet-triplet transition played a major role in the migration of excitation energy into triplet states. Among all tested compounds, substances with an OCH₃-group in the structure have the strongest effect on the spectral-luminescent characteristics.

Psoralen-loaded polymeric lipid nanoparticles combined with paclitaxel for the treatment of triple-negative breast cancer

Background: Chemotherapeutic drugs are associated with toxic effects. Metastasis is the leading cause of death in breast cancer patients. Aim: To evaluate the antitumor effect of paclitaxel (PTX) combined with psoralen-loaded polymeric lipid nanoparticles (PSO-PLNs) in triple-negative breast cancer. Methods: After treatment of samples, cell viability, apoptosis, migration, invasion, expression of proteins in the IRAK1/NF-κB/FAK signal pathway, biodistribution and pathological characteristics were detected. Results: Compared with the control group, the PTX + PSO-PLNs group showed increased apoptosis and reduced migration, invasion and expression of phosphorylated IRAK1 and NF-κB, with significant inhibition of tumor growth and lung metastases and no obvious toxicity. Conclusion: Combined administration of PTX and PSO-PLNs exerted a synergistic effect and significantly inhibited the growth and metastasis of triple-negative breast cancer.

Induction of G2/M Cell Cycle Arrest via p38/p21Waf1/Cip1-Dependent Signaling Pathway Activation by Bavachinin in Non-Small-Cell Lung Cancer Cells

Lung cancer is the most commonly diagnosed malignant cancer in the world. Non-small-cell lung cancer (NSCLC) is the major category of lung cancer. Although effective therapies have been administered, for improving the NSCLC patient’s survival, the incident rate is still high. Therefore, searching for a good strategy for preventing NSCLC is urgent. Traditional Chinese medicine (TCM) are brilliant materials for cancer chemoprevention, because of their high biological safety and low cost. Bavachinin, which is an active flavanone of Proralea corylifolia L., possesses anti-inflammation, anti-angiogenesis, and anti-cancer activities. The present study’s aim was to evaluate the anti-cancer activity of bavachinin on NSCLC, and its regulating molecular mechanisms. The results exhibited that a dose-dependent decrease in the cell viability and colony formation capacity of three NSCLC cell lines, by bavachinin, were through G2/M cell cycle arrest induction. Meanwhile, the expression of the G2/M cell cycle regulators, such as cyclin B, p-cdc2^Y15, p-cdc2^T161, and p-wee1, was suppressed. With the dramatic up-regulation of the cyclin-dependent kinase inhibitor, p21^Waf1/Cip1, the expression and association of p21^Waf1/Cip1 with the cyclin B/cdc2 complex was observed. Silencing the p21^Waf1/Cip1 expression significantly rescued bavachinin-induced G2/M cell accumulation. Furthermore, the expression of p21^Waf1/Cip1 mRNA was up-regulated in bavachinin-treated NSCLC cells. In addition, MAPK and AKT signaling were activated in bavachinin-added NSCLC cells. Interestingly, bavachinin-induced p21^Waf1/Cip1 expression was repressed after restraint p38 MAPK activation. The inhibition of p38 MAPK activation reversed bavachinin-induced p21^Waf1/Cip1 mRNA expression and G2/M cell cycle arrest. Collectively, bavachinin-induced G2/M cell cycle arrest was through the p38 MAPK-mediated p21^Waf1/Cip1-dependent signaling pathway in the NSCLC cells.

Anti-Cancer and Anti-Inflammatory Potential of Furanocoumarins from Ammi majus L

Secondary metabolites have potential benefits to human being. They are used in the food, agricultural and pharmaceutical industries. The secondary metabolite of furanocoumarins from different plant sources is essential in various skin-related ailments. Biologically, these chemicals are isolated from different plants in the Apiaceae, Fabaceae, Rutaceae and Moraceae families. Ammi Majus L. is one of the most common plants in the family of Apiaceae with a large quantity of derivatives. The furanocoumarin derivatives defend the plant by fighting external enemies by systemic acquired resistance (SAR). Via suppressing or retarding microbial growth in infected parts, these derivatives, along with SAR, help to alleviate inflammation in the human body. Latest evidence of these compounds has been established in the treatment of cancer, but the mechanism that needs to be elaborated is not yet understood. Recent studies have shown that furanocoumarin derivatives bind to DNA base pairs and block DNA replication. This may be a potential pathway that helps to regulate the growth of cancerous cells. This article reflects on the pharmaceutical data of furanocoumarins and their different mechanisms in these cases.

Bergapten: A review of its pharmacology, pharmacokinetics, and toxicity

Bergapten is a natural furocoumarin, also known as 5-methoxypsoralen, and its medicinal value has been paid more and more attention. By sorting out the pharmacological literature of bergapten, we found that bergapten has a wide range of pharmacological effects, including neuroprotection, organ protection, anticancer, antiinflammatory, antimicrobial, and antidiabetes effects. However，bergapten has complex impacts on the hepatic metabolic enzyme. Moreover, pharmacokinetic studies showed that bergapten has higher absolute bioavailability and can cross the blood-brain barrier and has a great potential for treating brain disease, but the mechanism needs further clarification to make greater use of its ability to treat brain diseases. Furthermore, the phototoxicity of bergapten combined with ultraviolet light has always been mentioned. In view of its wide range of pharmacological activities, bergapten is expected to be a potential drug candidate for the treatment of diabetes and diabetes-induced osteoporosis, epilepsy, Alzheimer's disease, depression, and cancer. However, further studies are needed to elucidate its molecular mechanisms and targets. The phototoxicity of bergapten as a side effect should be further avoided. On the other hand, the photoactivation of bergapten in the anticancer aspect can be better utilized.

Exploring the Potential of Aromatherapy as an Adjuvant Therapy in Cancer and its Complications: A Comprehensive Update

BACKGROUND

Aromatherapy is a traditional practice of employing essential oils for the therapeutic purposes, currently headed under the category of complementary and adjuvant medicine.

OBJECTIVE

The aim of this review article is to summarize the potential health benefits of aromatic essential oil from traditional times till the present. It also proposed some mechanisms which can be utilized as basis for using aromatherapy in cancer and cancer linked complications.

METHODS

To find out the relevant and authentic data, several search engines like Science direct, Pubmed, research gate, etc. were thoroughly checked by inserting key words like aromatherapy, complementary, adjuvant therapy etc. to collect the relevant material in context of article. Also, the chemical components of essential oil were classified based on the presence of functional groups, which are further explored for their cytotoxic potential.

RESULTS

The result depicted the anti-cancer potential of chemical constituents of essential oil against different types of cancer. Moreover, the essential oils show promising anti-inflammatory, anti-microbial, anti-oxidant and anti-mutagenic potential in several studies, which collectively can form the basis for initiation of its anti-cancer utility.

CONCLUSION

Aromatherapy can serve as adjuvant economic therapy in cancer after the standardization of protocol.

Assessment of Photo-Induced Cytotoxic Activity of Cachrys sicula and Cachrys libanotis Enriched-Coumarin Extracts against Human Melanoma Cells

Photochemotherapy is one of the most interesting current therapeutic approaches for the treatment of melanoma. Different classes of naturally occurring phytochemicals demonstrated interesting photoactive properties. The aim of this study was to evaluate the photocytotoxic potential of two Cachrys species from Southern Italy: C. sicula and C. libanotis (Apiaceae). The enriched-coumarin extracts were obtained from aerial parts through both traditional maceration and pressurized cyclic solid-liquid (PCSL) extraction using Naviglio extractor^®. Qualitative and quantitative analyses of furanocoumarins were performed with GC-MS. The photocytotoxic effects were verified on C32 melanoma cells irradiated at a dose of 1.08 J/cm². The apoptotic responses were also assessed. Moreover, phenolic content and the in vitro antioxidant potential were estimated. Xanthotoxin, bergapten, and isopimpinellin were identified. All the samples induced concentration-dependent photocytotoxic effects (IC₅₀ ranging from 3.16 to 18.18 μg/mL). The C. libanotis sample obtained with Naviglio extractor^® was the most effective one (IC₅₀ = 3.16 ± 0.21 μg/mL), followed by C. sicula sample obtained with the same technique (IC₅₀ = 8.83 ± 0.20 μg/mL). Both Cachrys samples obtained through PCSL induced up-regulation of apoptotic signals such as BAX (Bcl2-associated X protein) and PARP (poly ADP-ribose polymerase) cleavage. Moreover, these samples proved to be more photoactive, giving a greater upregulation of p21 protein in the presence of UVA radiation. Obtained results suggest that investigated species could be promising candidates for further investigations aimed to find new potential drugs for the photochemotherapy of skin cancer.

Anticancer Potential of Furanocoumarins: Mechanistic and Therapeutic Aspects

Cancer is one of the most extreme medical conditions in both developing and developed countries around the world, causing millions of deaths each year. Chemotherapy and/or radiotherapy are key for treatment approaches, but both have numerous adverse health effects. Furthermore, the resistance of cancerous cells to anticancer medication leads to treatment failure. The rising burden of cancer overall requires novel efficacious treatment modalities. Natural medications offer feasible alternative options against malignancy in contrast to western medication. Furanocoumarins' defensive and restorative impacts have been observed in leukemia, glioma, breast, lung, renal, liver, colon, cervical, ovarian, and prostate malignancies. Experimental findings have shown that furanocoumarins activate multiple signaling pathways, leading to apoptosis, autophagy, antioxidant, antimetastatic, and cell cycle arrest in malignant cells. Additionally, furanocoumarins have been shown to have chemo preventive and chemotherapeutic synergistic potential when used in combination with other anticancer drugs. Here, we address different pathways which are activated by furanocoumarins and their therapeutic efficacy in various tumors. Ideally, this review will trigger interest in furanocoumarins and their potential efficacy and safety as a cancer lessening agents.

Imperatorin as a Promising Chemotherapeutic Agent Against Human Larynx Cancer and Rhabdomyosarcoma Cells

Naturally occurring coumarins are bioactive compounds widely used in Asian traditional medicine. They have been shown to inhibit proliferation, induce apoptosis, and/or enhance the cytotoxicity of currently used drugs against a variety of cancer cell types. The aim of our study was to examine the antiproliferative activity of different linear furanocoumarins on human rhabdomyosarcoma, lung, and larynx cancer cell lines, and dissolve their cellular mechanism of action. The coumarins were isolated from fruits of Angelica archangelica L. or Pastinaca sativa L., and separated using high-performance counter-current chromatography (HPCCC). The identity and purity of isolated compounds were confirmed by HPLC-DAD and NMR analyses. Cell viability and toxicity assessments were performed by means of methylthiazolyldiphenyl-tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays, respectively. Induction of apoptosis and cell cycle progression were measured using flow cytometry analysis. qPCR method was applied to detect changes in gene expression. Linear furanocoumarins in a dose-dependent manner inhibited proliferation of cancer cells with diverse activity regarding compounds and cancer cell type specificity. Imperatorin (IMP) exhibited the most potent growth inhibitory effects against human rhabdomyosarcoma and larynx cancer cell lines owing to inhibition of the cell cycle progression connected with specific changes in gene expression, including CDKN1A. As there are no specific chemotherapy treatments dedicated to laryngeal squamous cell carcinoma and rhabdomyosarcoma, and IMP seems to be non-toxic for normal cells, our results could open a new direction in the search for effective anti-cancer agents.

Furanocoumarins in anticancer therapy - For and against

Furanocoumarins are a class of natural compounds produced by several plants, including those consumed by humans. They have been used medicinally in eastern countries for ages. Given the growing body of evidence about their anticancer potential and observations that naturally occurring compounds potentiate the antitumor activity of chemotherapeutics, more attention is paid to elucidation of the nature of furanocoumarins and the possibility of using thereof in practice. The general mechanism by which furanocoumarins eliminate cancer cells is based on cell cycle blockage and initiation of programmed death like apoptosis or autophagy. The precise molecular mechanism of such an action depends on the chemical structure of furanocoumarins, which is based on the furan ring attached to the coumarin backbone in a linear or angular form as well as the type, location, and number of the substituents attached. The review summarizes the current evidence of the antitumor properties of linear and angular furanocoumarins with special emphasis on the molecular mechanism of elimination of cancer cells via apoptosis and autophagy. Negative aspects of the use of coumarins in anticancer therapy will be also discussed especially in the context of their phototoxicity and potential cancerogenic effect.

Microwave-assisted synthesis, biological evaluation and molecular docking studies of new coumarin-based 1,2,3-triazoles

Coumarin-based 1,4-disubstituted 1,2,3-triazole derivatives were synthesized using a highly efficient, eco-friendly protocol via a copper(i)-catalyzed click reaction between various substituted arylazides and terminal alkynes.

Structure Based Multitargeted Molecular Docking Analysis of Selected Furanocoumarins against Breast Cancer

Breast cancer is one of the biggest global dilemmas and its current therapy is to target the hormone receptors by the use of partial agonists/antagonists. Potent drugs for breast cancer treatment are Tamoxifen, Trastuzumab, Paclitaxel, etc. which show adverse effects and resistance in patients. The aim of the study has been on certain phytochemicals which has potent actions on ERα, PR, EGFR and mTOR inhibition. The current study is performed by the use of molecular docking as protein-ligand interactions play a vital role in drug design. The 3D structures of ERα, PR, EGFR and mTOR were obtained from the protein data bank and docked with 23 3D PubChem structures of furanocoumarin compounds using FlexX. Drug-likeness property was checked by applying the Lipinski's rule of five on the furanocoumarins to evaluate anti-breast cancer activity. Antagonist and inhibition assay of ERα, EGFR and mTOR respectively has been performed using appropriate in-vitro techniques. The results confirm that Xanthotoxol has the best docking score for breast cancer followed by Bergapten, Angelicin, Psoralen and Isoimperatorin. Further, the in-vitro results also validate the molecular docking analysis. This study suggests that the selected furanocoumarins can be further investigated and evaluated for breast cancer treatment and management strategies.

Botanical Sources, Chemistry, Analysis, and Biological Activity of Furanocoumarins of Pharmaceutical Interest

The aim of this work is to provide a critical review of plant furanocoumarins from different points of view, including their chemistry and biosynthetic pathways to their extraction, analysis, and synthesis, to the main biological activities found for these active compounds, in order to highlight their potential within pharmaceutical science. The limits and the possible improvements needed for research involving these molecules are also highlighted and discussed.

Polymer-lipid hybrid nanoparticles: A novel drug delivery system for enhancing the activity of Psoralen against breast cancer

A polymer-lipid hybrid nanocarrier was developed to encapsulate psoralen (PSO) to improve its water solubility and bioavailability. The effects of PSO-loaded polymer-lipid hybrid nanoparticles (PSO-PLNs) on breast cancer MCF-7 cells were investigated. PSO-PLNs were prepared through a nanoprecipitation method and were optimized by a central composite design-response surface methodology using particle size and entrapment efficiency as indices. Dynamic light scattering and transmission electron microscopy analysis confirmed the physicochemical characterizations of PSO-PLNs, which had an average size of 93.44 ± 2.39 nm and a zeta potential of -27.63 ± 0.31 mV. In vitro drug release of PSO-PLNs was evaluated using dialysis and showed a delayed release compared with free PSO. The in vivo anticancer efficiency of PSO-PLNs was appreciated using a MCF-7 breast tumor model. Administration of PSO-PLNs showed similar antitumor efficacy but lower toxicity compared with doxorubicin. Our designed nanocarriers successfully optimized the pharmacokinetics of PSO via improved systemic delivery.

Psoralen induced cell cycle arrest by modulating Wnt/β-catenin pathway in breast cancer cells

Psoralen could inhibit the proliferation of human breast cancer cells, however, the molecular mechanism was unclear. We evaluated the anti-proliferative effects of psoralen by MTT, plate colony formation assay and cell cycle analysis in MCF-7 and MDA-MB-231 cells. The effects of psoralen on activation of Wnt/β-catenin and the related target genes were examined by quantitative real-time PCR, western blotting and cell immunofluorescence. The tumor growth was conducted in BALB/c nude mice and the pathological changes of heart, liver and kidney were also observed. Our results demonstrate that psoralen significantly inhibited cell proliferation by inducing G0/G1 phase arrest in MCF-7 cells and G2/M phase arrest in MDA-MB-231 cells. The expression of Fra-1 was reduced and Axin2 was promoted both in MCF-7 and MDA-MB-231 cells after psoralen treatment. The cytoplasmic accumulation and nuclear translocation of β-catenin were significantly reduced by psoralen. Psoralen increased the levels of phospho-(Y142) β-catenin, while decreased the expression of total β-catenin and its downstream target Fra-1 in vitro and vivo. Moreover, psoralen didn’t cause any significant toxicity at the effective concentration. Overall, our results might provide theoretical basis for clinical application of psoralen in breast cancer.

Extracts and components of Ficus carica leaves suppress survival, cell cycle, and migration of triple-negative breast cancer MDA-MB-231 cells

Background

Products from Ficus carica have been used in traditional medicine to treat many diseases. This study aimed to analyze anticancer effects of extracts of F. carica leaves on the triple-negative breast cancer cell line MDA-MB-231.

Materials and methods

The human breast cancer cell line MDA-MB-231 was used to evaluate effects of F. carica extracts. Effects of F. carica on cell viability were evaluated using MTT assays. Cell-cycle distribution was examined using cell-cycle analysis. Wound-healing assays were used to evaluate migration of MDA-MB-231. Quantitative reverse-transcription polymerase chain reaction was used to detect levels of Bax, p53, p21, GATA3, ELF5, cyclin-dependent kinases, MMP2, and tissue inhibitors of metalloproteinase.

Results

We investigated the mechanism of anti-growth effects, and found that the expressions of genes that promote apoptosis were increased. In addition, the treated cells illustrated increased portion at S phase and changed expression of cyclin-dependent kinases, demonstrating cell-cycle arrest at the S phase. Furthermore, treated cells showed decreased cell mobility, which is essential for metastasis. Two of the active components of F. carica leaves, bergapten and psoralen, had similar anticancer effects as F. carica leaf extracts, indicating that these two components might play important roles in anticancer effects of F. carica leaves.

Conclusion

Our findings suggest that F. carica leaves might be a good source to develop drugs for suppressing cancer-cell growth and migration to treat triple-negative breast cancers.

Ground- and Excited-State Interactions of a Psoralen Derivative with Human Telomeric G-Quadruplex DNA

G-quadruplex DNA has been a recent target for anticancer agents, and its binding interactions with small molecules, often used as anticancer drugs, have become an important area of research. Considering that psoralens have long been studied in the context of duplex DNA but that very little is known about their potential as G-quadruplex binders and their excited-state interaction with the latter has not been explored, we have studied herein the binding of a planar water-soluble psoralen derivative, 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT), with the 22-mer human telomeric G-quadruplex-forming sequence, AGGG(TTAGGG)₃, labeled here as (hTel22), and investigated the consequences of photoexcitation of AMT by calorimetric and spectroscopic techniques. The results show an enthalpy-driven 1:1 binding of AMT with hTel22 via end-stacking mode. Fluorescence quenching experiments on 6-fluorescein amidite-labeled oligomers indicate that the binding site is nearer to the 3' end of hTel22 in the diagonal loop region. Femtosecond time-resolved transient absorption measurements indicate electron transfer from the guanine moiety of hTel22 to photoexcited AMT, leading to the formation of a radical pair species (AMT^•-G^•+), which survives for 30 ps and is favored by a parallel/quasi-parallel orientation between the two. The findings reveal psoralens as a prospective class of compounds for the development of anticancer therapeutics by targeting the G-quadruplex DNA.

X-Ray Psoralen Activated Cancer Therapy (X-PACT)

This work investigates X-PACT (X-ray Psoralen Activated Cancer Therapy): a new approach for the treatment of solid cancer. X-PACT utilizes psoralen, a potent anti-cancer therapeutic with current application to proliferative disease and extracorporeal photopheresis (ECP) of cutaneous T Cell Lymphoma. An immunogenic role for light-activated psoralen has been reported, contributing to long-term clinical responses. Psoralen therapies have to-date been limited to superficial or extracorporeal scenarios due to the requirement for psoralen activation by UVA light, which has limited penetration in tissue. X-PACT solves this challenge by activating psoralen with UV light emitted from novel non-tethered phosphors (co-incubated with psoralen) that absorb x-rays and re-radiate (phosphoresce) at UV wavelengths. The efficacy of X-PACT was evaluated in both in-vitro and in-vivo settings. In-vitro studies utilized breast (4T1), glioma (CT2A) and sarcoma (KP-B) cell lines. Cells were exposed to X-PACT treatments where the concentrations of drug (psoralen and phosphor) and radiation parameters (energy, dose, and dose rate) were varied. Efficacy was evaluated primarily using flow cell cytometry in combination with complimentary assays, and the in-vivo mouse study. In an in-vitro study, we show that X-PACT induces significant tumor cell apoptosis and cytotoxicity, unlike psoralen or phosphor alone (p<0.0001). We also show that apoptosis increases as doses of phosphor, psoralen, or radiation increase. Finally, in an in-vivo pilot study of BALBc mice with syngeneic 4T1 tumors, we show that the rate of tumor growth is slower with X-PACT than with saline or AMT + X-ray (p<0.0001). Overall these studies demonstrate a potential therapeutic effect for X-PACT, and provide a foundation and rationale for future studies. In summary, X-PACT represents a novel treatment approach in which well-tolerated low doses of x-ray radiation are delivered to a specific tumor site to generate UVA light which in-turn unleashes both short- and potentially long-term antitumor activity of photo-active therapeutics like psoralen.