Modulating effect of DL-kavain on the mutagenicity and carcinogenicity induced by doxorubicin in Drosophila melanogaster

A Drosophila model relevant to chemotherapy-related cognitive impairment

Chemotherapy-related cognitive impairment (CRCI) is a common adverse effect of treatment and is characterized by deficits involving multiple cognitive domains including memory. Despite the significant morbidity of CRCI and the expected increase in cancer survivors over the coming decades, the pathophysiology of CRCI remains incompletely understood, highlighting the need for new model systems to study CRCI. Given the powerful array of genetic approaches and facile high throughput screening ability in Drosophila, our goal was to validate a Drosophila model relevant to CRCI. We administered the chemotherapeutic agents cisplatin, cyclophosphamide, and doxorubicin to adult Drosophila. Neurologic deficits were observed with all tested chemotherapies, with doxorubicin and in particular cisplatin also resulting in memory deficits. We then performed histologic and immunohistochemical analysis of cisplatin-treated Drosophila tissue, demonstrating neuropathologic evidence of increased neurodegeneration, DNA damage, and oxidative stress. Thus, our Drosophila model relevant to CRCI recapitulates clinical, radiologic, and histologic alterations reported in chemotherapy patients. Our new Drosophila model can be used for mechanistic dissection of pathways contributing to CRCI (and chemotherapy-induced neurotoxicity more generally) and pharmacologic screens to identify disease-modifying therapies.

Genotoxic action of bifenthrin nanoparticles and its effect on the development, productivity, and behavior of Drosophila melanogaster

Rapid development of nanotechnology, particularly nanoparticles of pesticides, has facilitated the transformation of traditional agriculture. However, testing their effectiveness is essential for avoiding any environmental or adverse human health risk attributed to nanoparticle-based formulations, especially insecticides. Recently, organic nanoparticles of bifenthrin, a pyrethroid insecticide, were successfully synthesized by laser ablation of solids in liquid technique, with the most probable size of 5 nm. The aim of the present study was to examine the effects of acute exposure to bifenthrin (BIF) or bifenthrin nanoparticles (BIFNP) on larval-adult viability, developmental time, olfactory capacity, longevity, productivity defined as the number of eggs per couple, and genotoxicity in Drosophila melanogaster. Data demonstrated that BIFNP produced a marked delay in developmental time, significant reduction in viability and olfactory ability compared to BIF. No marked differences were detected between BIF and BIFNP on longevity and productivity. Genotoxicity findings indicated that only BIF, at longer exposure duration increased genetic damage.

A Drosophila model of chemotherapy-related cognitive impairment

Chemotherapy-related cognitive impairment (CRCI) is a common adverse effect of treatment and is characterized by deficits involving multiple cognitive domains including memory. Despite the significant morbidity of CRCI and the expected increase in cancer survivors over the coming decades, the pathophysiology of CRCI remains incompletely understood, highlighting the need for new model systems to study CRCI. Given the powerful array of genetic approaches and facile high throughput screening ability in Drosophila, our goal was to validate a Drosophila model of CRCI. We administered the chemotherapeutic agents cisplatin, cyclophosphamide, and doxorubicin to adult Drosophila. Neurocognitive deficits were observed with all tested chemotherapies, especially cisplatin. We then performed histologic and immunohistochemical analysis of cisplatin-treated Drosophila tissue, demonstrating neuropathologic evidence of increased neurodegeneration, DNA damage, and oxidative stress. Thus, our Drosophila model of CRCI recapitulates clinical, radiologic, and histologic alterations reported in chemotherapy patients. Our new Drosophila model can be used for mechanistic dissection of pathways contributing to CRCI and pharmacologic screens to identify novel therapies to ameliorate CRCI.

α-tocopherol as a selective modulator of toxicogenic damage induced by antineoplastic agents cyclophosphamide and doxorubicin

The aim of this study was to determine the oxidative/antioxidative effects, modulatory and selective potential of α-tocopherol (vitamin E) on antineoplastic drug-induced toxicogenetic damage. The toxicity, cytotoxicity and genotoxicity induced by antineoplastic agents cyclophosphamide (CPA) and doxorubicin (DOX) was examined utilizing as models Saccharomyces cerevisiae, Allium cepa, Artemia salina and human peripheral blood mononuclear cells (PBMCs) in the presence of α-tocopherol. For these tests, concentrations of α- tocopherol 100 IU/ml (67mg/ml), CPA 20 µg/ml, DOX 2 µg/ml were used. The selectivity of α-tocopherol was assessed by the MTT test using human mammary gland non-tumor (MCF10A) and tumor (MCF-7) cell lines. Data showed cytoplasmic and mitochondrial oxidative damage induced by CPA or DOX was significantly diminished by α-tocopherol in S. cerevisiae. In addition, the toxic effects on A. salina and cytotoxic and mutagenic effects on A. cepa were significantly reduced by α-tocopherol. In PBMCs, α-tocopherol alone did not markedly affect these cells, and when treated in conjunction with CPA or DOX, α-tocopherol reduced the toxicogenetic effects noted after antineoplastic drug administration as evidenced by decreased chromosomal alterations and lowered cell death rate. In human mammary gland non-tumor and tumor cell lines, α-tocopherol produced selective cytotoxicity with 2-fold higher effect in tumor cells. Evidence indicates that vitamin E (1) produced anti-cytotoxic and anti-mutagenic effects against CPA and DOX (2) increased higher selectivity toward tumor cells, and (3) presented chemoprotective activity in PBMCs.

CircRNA-Based Cervical Cancer Prognosis Model, Immunological Validation and Drug Prediction

BACKGROUND

Cervical cancer (CC) is a common cancer in female, which is associated with problems like poor prognosis. Circular RNA (circRNA) is a kind of competing endogenous RNA (ceRNA) that has an important role in regulating microRNA (miRNA) in many cancers. The regulatory mechanisms of CC immune microenvironment and the transcriptome level remain to be fully explored.

METHODS

In this study, we constructed the ceRNA network through the interaction data and expression matrix of circRNA, miRNA and mRNA. Meanwhile, based on the gene expression matrix, CIBERSORT algorithm was used to reveal contents of tumor-infiltrating immune cells (TIICs). Then, we screened prognostic markers based on ceRNA network and immune infiltration and constructed two nomograms. In order to find immunological differences between the high- and low-risk CC samples, we examined multiple immune checkpoints and predicted the effect of PD-L1 ICI immunotherapy. In addition, the sensitive therapeutics for high-risk patients were screened, and the potential agents with anti-CC activity were predicted by Connective Map (CMap).

RESULTS

We mapped a ceRNA network including 5 circRNAs, 17 miRNAs and 129 mRNAs. From the mRNA nodes of the network six genes and two kind of cells were identified as prognostic makers for CC. Among them, there was a significant positive correlation between CD8+ T cells and SNX10 gene. The results of TIDE and single sample GSEA (ssGSEA) showed that T cells CD8 do play a key role in inhibiting tumor progression. Further, our study screened 24 drugs that were more sensitive to high-risk CC patients and several potential therapeutic agents for reference.

CONCLUSIONS

Our study identified several circRNA-miRNA-mRNA regulatory axes and six prognostic genes based on the ceRNA network. In addition, through TIIC, survival analysis and a series of immunological analyses, T cells were proved to be good prognostic markers, besides play an important role in the immune process. Finally, we screened 24 potentially more effective drugs and multiple potential drug compounds for high- and low-risk patients.

An Updated Review on the Psychoactive, Toxic and Anticancer Properties of Kava

Kava (Piper methysticum) has been widely consumed for many years in the South Pacific Islands and displays psychoactive properties, especially soothing and calming effects. This plant has been used in Western countries as a natural anxiolytic in recent decades. Kava has also been used to treat symptoms associated with depression, menopause, insomnia, and convulsions, among others. Along with its putative beneficial health effects, kava has been associated with liver injury and other toxic effects, including skin toxicity in heavy consumers, possibly related to its metabolic profile or interference in the metabolism of other xenobiotics. Kava extracts and kavalactones generally displayed negative results in genetic toxicology assays although there is sufficient evidence for carcinogenicity in experimental animals, most likely through a non-genotoxic mode of action. Nevertheless, the chemotherapeutic/chemopreventive potential of kava against cancer has also been suggested. Both in vitro and in vivo studies have evaluated the effects of flavokavains, kavalactones and/or kava extracts in different cancer models, showing the induction of apoptosis, cell cycle arrest and other antiproliferative effects in several types of cancer, including breast, prostate, bladder, and lung. Overall, in this scoping review, several aspects of kava efficacy and safety are discussed and some pertinent issues related to kava consumption are identified.

Protective effect of kavain in meristematic cells of Allium cepa L

Kavain is one of the main kavalactones of Piper methysticum (Piperaceae) with anxiolytic, analgesic, and antioxidant activities. Therefore, the aim of the study was to evaluate the cytotoxic, mutagenic, and antimutagenic potential of kavain in Allium cepa cells. Roots of A. cepa were transferred to the negative (2% acetone) and positive (10 µg/mL of Methylmethanesulfonate, MMS) controls and to the concentrations of kavain (32, 64 and 128 µg/mL) for 48 h. A total of 5,000 meristematic cells were analyzed under an optical microscope to determine the mitotic index, mean number of chromosomal alterations and percentage of damage reduction. Data were analyzed by Kruskal-Wallis test (p <0.05). All concentrations of kavain were not cytotoxic and did not show significant chromosomal changes when compared to 2% acetone. Kavain showed a cytoprotective effect in the pre (128 μg/mL) and in the post-treatment (32 and 64 μg/mL) and reduced damage against the mutagenic action of MMS in all concentrations of the pre and simultaneous and at the highest of post (128 μg/mL). Kavain promoted a significant reduction in micronuclei, nuclear buds and chromosomal losses in relation to MMS. The observed data indicate the importance of kavain for the inhibition of damage and chemoprevention.

In vivo effects of 1,4-dioxane on genotoxic parameters and behavioral alterations in Drosophila melanogaster

1,4-Dioxane (DXN) is used as solvent in different consumer products including cosmetics, paints, surfactants, and waxes. In addition, DXN is released as an unwanted contaminating by-product as a result of some reactions including ethoxylation of alcohols, which occurs with in personal care products. Consequently, DXN pollution was detected in drinking water and is considered as an environmental problem. At present, the genotoxicity effects attributed to DXN are controversial. The present study using an in vivo model organism Drosophila melanogaster aimed to determine the toxic/genotoxic, mutagenic/recombinogenic, oxidative damage as evidenced by ROS production, phenotypic alterations as well as behavioral and developmental alterations that are closely related to neuronal functions. Data demonstrated that nontoxic DXN concentration (0.1, 0.25, 0.5, or 1%) induced mutagenic (1%) and recombinogenic (0.1, 0.25, or 0.5%) effects in wing spot test and genotoxicity in hemocytes using comet assay. The nontoxic concentrations of DXN (0.1, 0.25, 0.5, or 1%) significantly increased oxidative stress, climbing behavior, thermal sensivity and abnormal phenotypic alterations. Our findings show that in contrast to in vitro exposure, DXN using an in vivo model Drosophila melanogaster this compound exerts toxic and genotoxic effects. Data suggest that additional studies using other in vivo models are thus warranted.

Antitumor activity of solamargine in mouse melanoma model: relevance to clinical safety

Melanoma is the most aggressive type of skin cancer, and thus it is important to develop new drugs for its treatment. The present study aimed to examine the antitumor effects of solamargine a major alkaloid heteroside present in Solanum lycocarpum fruit. In addition solamargine was incorporated into nanoparticles (NP) of yttrium vanadate functionalized with 3-chloropropyltrimethoxysilane (YVO₄:Eu³⁺:CPTES:SM) to determine antitumor activity. The anti-melanoma assessment was performed using a syngeneic mouse melanoma model B16F10 cell line. In addition, systemic toxicity, nephrotoxic, and genotoxic parameters were assessed. Solamargine, at doses of 5 or 10 mg/kg/day administered subcutaneously to male C57BL/6 mice for 5 days, decreased tumor size and frequency of mitoses in tumor tissue, indicative of a decrease in cell proliferation. Treatments with YVO₄:Eu³⁺:CPTES:SM significantly reduced the number of mitoses in tumor tissue, associated with no change in tumor size. There were no apparent signs of systemic toxicity, nephrotoxicity, and genotoxicity initiated by treatments either with solamargine alone or plant alkaloid incorporated into NP. The animals treated with YVO₄:Eu³⁺:CPTES:SM exhibited significant increase in spleen weight accompanied by no apparent histological changes in all tissues examined. In addition, animals treated with solamargine (10 mg/kg/day) and YVO₄:Eu³⁺:CPTES:SM demonstrated significant reduction in hepatic DNA damage which was induced by tumor growth. Therefore, data suggest that solamargine may be considered a promising candidate in cancer therapy with no apparent toxic effects.

Arrabidaea chica chloroform extract modulates estrogen and androgen receptors on luminal breast cancer cells

BACKGROUND

Breast Cancer (BC) is the most common cancer in women worldwide and, although 70% of patients are responsive to selective Estrogen Receptor (ER) modulators such as Tamoxifen (Tam), patients' survival is comprised by resistance to endocrine therapy. Brazilian flora, especially the Amazon biome, is one of the richest global sources of native species with potentially bioactive compounds. Arrabidaea chica is a plant native to the Amazon that has been used in the treatment of different diseases. However, its action on BC remains unclear.

METHODS

Herein the biological effects of the chloroform extract of A. chica (CEAC) were evaluated on BC cells and in in vivo model. After confirmation of CEAC antioxidant capacity, cells were treated with CEAC and Tam, alone and with CEAC+Tam. The cell viability was evaluated by MTT and hormone receptor transcripts levels were assessed (ESR1, ESR2 and AR). Finally, anticarcinogenicity of CEAC was recorded in Drosophila melanogaster through Epithelial Tumor Test (ETT).

RESULTS

The study confirmed the antioxidant activity of CEAC. CEAC was selective for MCF-7, downregulating ESR2 and AR transcripts and upregulating ESR2 expression. The modulatory effects of CEAC on ERs did not differ between cells treated with Tam and with CEAC+Tam. Interestingly, previous treatment with CEAC, followed by treatment with Tam promoted a significant decrease in cell viability. The extract also presented anticarcinogenic effect in in vivo assay.

CONCLUSION

The bioassays on breast tumor cells demonstrated the antiproliferative activity of the extract, which modulated the expression of hormone receptors and sensitized luminal tumor cells to Tam. These results suggest that CEAC could be a complementary treatment for BC.