In Vitro Evidence of Differential Immunoregulatory Response between MDA-MB-231 and BT-474 Breast Cancer Cells Induced by Bone Marrow-Derived Mesenchymal Stromal Cells Conditioned Medium

Inside tumors, cancer cells display several mechanisms to create an immunosuppressive environment. On the other hand, by migration processes, mesenchymal stromal cells (MSCs) can be recruited by different cancer tumor types from tissues as distant as bone marrow and contribute to tumor pathogenesis. However, the impact of the immunoregulatory role of MSCs associated with the aggressiveness of breast cancer cells by soluble molecules has not been fully elucidated. Therefore, this in vitro work aimed to study the effect of the conditioned medium of human bone marrow-derived-MSCs (hBM-MSC-cm) on the immunoregulatory capability of MDA-MB-231 and BT-474 breast cancer cells. The hBM-MSC-cm on MDA-MB-231 cells induced the overexpression of TGF-β, IDO, and IL-10 genes. Additionally, immunoregulation assays of mononuclear cells (MNCs) in co-culture with MDA-MB-231 and hBM-MSC-cm decreased lymphocyte proliferation, and increased proteins IL-10, TGF-β, and IDO while also reducing TNF levels, shooting the proportion of regulatory T cells. Conversely, the hBM-MSC-cm did not affect the immunomodulatory capacity of BT-474 cells. Thus, a differential immunoregulatory effect was observed between both representative breast cancer cell lines from different origins. Thus, understanding the immune response in a broader tumor context could help to design therapeutic strategies based on the aggressive behavior of tumor cells.

Standardized phytopreparations and cucurbitacin IIb from Ibervillea sonorae (S. Watson) greene induce apoptosis in cervical cancer cells by Nrf2 inhibition

ETHNOPHARMACOLOGY RELEVANCE

Ibervillea sonorae (S. Watson) Greene is a plant from northwestern Mexico, known as "Wereke" or "Guareque", used by the Mayo ethnic group to treat diabetes and cancer. Cucurbitacin IIb (CIIb), isolated from I. sonorae has apoptotic and antitumor activity in a model of cervical cancer with the HeLa cell line. One pathway affected by cucurbitacins is Nrf2, a glutathione transferase (GST) transcription factor, important in the regulation of mitochondrial oxidative stress (MOS). A signal of MOS is the change in the mitochondrial membrane potential (ΔΨm), which has been detected in HeLa in the presence of CIIb. Fito-Ison-EtOH (Etanison) and Fito-Ison-EtOAc (Acetison) are phytopreparations from I. sonorae standardized according to their CIIb content (6.7 mg/g and 18.4 mg/g of CIIb, respectively). Etanison and Acetison have been reported to induce morphological changes in HeLa like those induced by CIIb.

AIM OF THE STUDY

To evaluate the apoptotic and Nrf2 inhibition activity of the phytopreparations Acetison and Etanison from Ibervillea Sonorae in the HeLa cervical cancer cell line.

MATERIALS AND METHODS

Antiproliferative activity was evaluated by the MTT method at 24, 48, and 72 h. For Acetison and Etanison, serial concentrations from 6.25 μg/mL to 100 μg/mL were tested, and for CIIb from 1.56 μg/mL to 50 μg/mL. The expression of Nrf2, caspase 3, and caspase 9 was evaluated by western blot, using concentrations of 30 μg/mL for Acetison, 50 μg/mL for Etanison, and 15 μg/mL for CIIb. Cisplatin was used as a positive control.

RESULTS AND CONCLUSIONS

Apoptotic activity of Etanison and Acetison was demonstrated in HeLa, due to the presence of caspase-9 and caspase-3 in western blot assays. Likewise, both the phytopreparations and CIIb showed inhibition of Nrf2, associating apoptotic activity with the inhibition of the GST transcription factor. In this sense, the phytopreparations of I. sonorae, as well as their derivatives, have the potential to obtain and develop anticancer products.

Antiproliferative activity of standardized phytopreparations from Ibervillea sonorae (S. Watson) Greene

Ibervillea sonorae (Cucurbitaceae) is a medicinal plant utilized in Northwest Mexico against Diabetes and cancer. This natural product is taken orally, its presentation is capsules containing the plant's dried and powdered caudices. There is no regulation or standardized dosage that allows reproducibility of its pharmacological effects. Cucurbitacins are the main group of compounds found in I. sonorae and are known for their antiproliferative activity in cancer cells. Cucurbitacin IIb (CIIb), one of the compounds present in I. sonorae, has demonstrated in experimental models with HeLa cervical cancer cells an apoptotic and anti-tumoral activity. The objective of this study is to obtain and standardize two phytopreparations of I. sonorae based on their CIIb content, evaluate their antiproliferative activity in cancer cell lines, and compare the results with those obtained with CIIb; expecting to find phytopreparations with anti-cancer potential. APCI-IT-MSn is utilized for the identification of cucurbitacins, FT-ICR-MS/MS for the quantification of CIIb, and the MTT assay for the evaluation of the antiproliferative activity. The CIIb content was 0.67% for Fito-Ison-EtOH and 1.84% for Fito-Ison-EtOAc. In both phytopreparations, six cucurbitacins have been identified, and a seventh one not previously identified. Phytopreparations were more effective against HeLa, with IC₅₀ of 30.0 and 18.6 µg/mL for Fito-Ison-EtOH and Fito-Ison-EtOAc, respectively. This effect is lower than observed on CIIb in HeLa (5.8 µg/mL). There are no significant differences (p > 0.05) in the antiproliferative activity between Fito-Ison-EtOAc and CIIb in A549, LS180, and MDA-MB-231 cells. Phytopreparations of I. sonorae have potential for the development of anti-cancer products.

Data on sodium tetraborate as a modulation of hypertrophic intracellular signals

The present work benefits the use of sodium tetraborate to prevent and treat hypertrophic cardiac. The data obtained from the work could serve as a reference point to compare with data obtained in vivo studies with cardiac damage. This research will be an advantage for future researches to stimulate the ones focused on developing food supplements to prevent heart diseases such as cardiac hypertrophic. This article also indicates the data on the optimal concentration of isoproterenol as an inducer of hypertrophy in cardiomyocytes. Also, data of the cytotoxic effect of sodium tetraborate on normal cardiomyocytes is revealed. Finally, data of viability, cell size, proliferation nuclear antigen (PCNA) and apoptosis is shown. The expression of transcription factors linked to hypertrophy such as GATA-4, MEF2c, NFAT, CDk9, and myogenin was also quantified by immunofluorescence. The mRNA expression of adrenergic receptors (alpha and beta), AKT1 and Erk1 / 2 and genes of early response to hypertrophy (c-myc, c-fos, c-jun) are also shown as Cts of RT-qPCR. GAPDH and 18 s were used as housekeeping genes.

Role of sodium tetraborate as a cardioprotective or competitive agent: Modulation of hypertrophic intracellular signals

Boron is an essential trace element in cellular metabolism; however, the molecular mechanism of boron in the heart is unclear. In this study, we examined the effect of sodium tetraborate (as boron source) as a possible protective agent or competitive inhibitor of cardiac hypertrophy in an in vitro murine model. We evaluated different previously reported sodium tetraborate concentrations and it was found that 13 μM improves viability without affecting the cellular structure. We demonstrated that cardiomyocytes pretreated with sodium tetraborate prevents cellular damage induced by isoproterenol (cardioprotective effect) by increasing proliferation rate and inhibiting apoptosis. In addition, the reduction of the expression of the α1AR and β1AR adrenergic receptors as well as Erk1/2 was notable. Consequently, the expression of the early response genes c-myc, c-fos and c-jun was delayed. Also, the expression of GATA-4, NFAT, NKx2.5 and myogenin transcription factors involved in sarcomere synthesis declined. In contrast, cardiomyocytes, when treated simultaneously with sodium tetraborate and isoproterenol, did not increase their size (cytoplasmic gain), but an increase in apoptosis levels was observed; therefore, the proliferation rate was reduced. Although the mRNA levels of α1AR and β1AR as well as Erk1/2 and Akt1 were low at 24 h, their expression increased to 48 h. Notably, the mRNA of expression levels of c-myc, c-fos and c-jun were lower than those determined in the control, while the transcription factors GATA-4, MEF2c, Nkx2.5, NFAT and CDk9 were determined in most cells. These results suggest that pretreatment with sodium tetraborate in cardiomyocytes inhibits the hypertrophic effect. However, sodium tetraborate attenuates isoproterenol induced hypertrophy damage in cardiomyocytes when these two compounds are added simultaneously.

Cucurbitacin IIb from Ibervillea sonorae Induces Apoptosis and Cell Cycle Arrest via STAT3 Inhibition

Background:

Cucurbitacin IIb (CIIb) from Ibervillea sonorae has a high capacity to suppress cancer cell proliferation and induce apoptosis. This study investigated the molecular mechanisms related to the antiproliferative and apoptosis induction capacity of CIIb in HeLa cells.

Materials and Methods:

The cell viability and anti-proliferative effect of CIIb were evaluated by using the trypan blue exclusion assay. The effect of CIIb on the mitochondrial membrane potential was determined by flow cytometry using JC-1. The activity of caspase-3 and caspase-9 was evaluated by flow cytometry using commercial kits. The effect of CIIb on the cell cycle was investigated using Fluorescence-Activated Cell Sorting (FACS) analysis. Western blot analysis was used to evaluate both the inhibitory effect of CIIb on the STAT3 signaling pathway and cyclin –B1, and DNA damage by the comet assay.

Results:

CIIb triggers disruption of the mitochondrial membrane potential (Δψm) and consequently activated the caspases -3 and -9, as a result of the activation of the intrinsic pathway of the apoptosis. Likewise, the CIIbinduced cell cycle was arrested in S and G2/M after 24h of treatment. CIIb also reduced the expression of STAT3 and cyclin –B1. Finally, CIIb produced an antiproliferative effect at 48 and 72 h, inducing DNA damage.

Conclusion:

These results demonstrate CIIb-induced apoptosis and cell cycle arrest in HeLa through the inhibition of STAT3.

Evaluating the biological risk of functionalized multiwalled carbon nanotubes and functionalized oxygen-doped multiwalled carbon nanotubes as possible toxic, carcinogenic, and embryotoxic agents

Carbon nanotubes (CNTs) have been a focus of attention due to their possible applications in medicine, by serving as scaffolds for cell growth and proliferation and improving mesenchymal cell transplantation and engraftment. The emphasis on the benefits of CNTs has been offset by the ample debate on the safety of nanotechnologies. In this study, we determine whether functionalized multiwalled CNTs (fMWCNTs) and functionalized oxygen-doped multiwalled CNTs (fCOxs) have toxic effects on rat mesenchymal stem cells (MSCs) in vitro by analyzing morphology and cell proliferation and, using in vivo models, whether they are able to transform MSCs in cancer cells or induce embryotoxicity. Our results demonstrate that there are statistically significant differences in cell proliferation and the cell cycle of MSCs in culture. We identified dramatic changes in cells that were treated with fMWCNTs. Our evaluation of the transformation to cancer cells and cytotoxicity process showed little effect. However, we found a severe embryotoxicity in chicken embryos that were treated with fMWCNTs, while fCOxs seem to exert cardioembryotoxicity and a discrete teratogenicity. Furthermore, it seems that the time of contact plays an important role during cell transformation and embryotoxicity. A single contact with fMWCNTs is not sufficient to transform cells in a short time; an exposure of fMWCNTs for 2 weeks led to cell transformation risk and cardioembryotoxicity effects.

STR data for 15 loci in a population sample from the central region of Mexico

A Mexican population sample was obtained from the central region of the country, including five states. Two hundred and eleven individuals were PCR-typed for 15 STR loci with the AmpFiota STR Identifiler PCR amplification kit (Applied Biosystems). The following autosomal markers were analyzed: D8S1179, D21S11, D7S820, CSF1PO, D19S433, vWA, TPOX, D18S51, D3S1358, TH01, D13S317, D16S539, D2S1338, D5S818, FGA and Amelogenin. Allele frequencies for each STR were estimated and compared to previous reports. Genotype distribution by locus and by two loci combination was in agreement with Hardy-Weinberg expectations for all 15 STRs. This STR system in Mexican-mestizos presented a combined probability of exclusion (PE) and discrimination (PD) longer than 99.999%.

Uptake of (188)Re-beta-naphthyl-peptide in cervical carcinoma tumours in athymic mice

Radiolabelled somatostatin analogues have been used in diagnostic and therapeutic nuclear medicine to treat cancerous tumours. Lanreotide, a cyclic octapeptide, beta-naphthyl-peptide, with antiproliferative action on human small cell lung carcinoma was (188)Re labelled and characterised, and its biodistribution was studied in mice. Molecular modelling indicates that the lipophilic radiopharmaceutical might be an oxo-rhenium (V) penta-coordinated complex. The implanted human cervical tumour of epidermoid origin was positive for cytokeratins and Vimentin. Uptake of (188)Re-labelled peptide in the implanted tumour in athymic mice was 6.2+/-2.9% and was rapidly cleared via the hepatobiliary system. (188)Re-beta-naphthyl-peptide might be a potential therapeutic agent.

Uptake of the 188Re(V)-DMSA complex by cervical carcinoma cells in nude mice: pharmacokinetics and dosimetry

The uptake of the rhenium-188 (188Re(V)-DMSA) complex of dimercaptosuccinic acid by cervical carcinoma cells in nude mice was evaluated. The pharmacokinetics and dosimetry calculations in normal rats were also evaluated. The images obtained in mice did not show significant accumulation in metabolic organs and the biodistribution studies showed that 3.52 +/- 0.76% of the injected activity per gram (n = 4) was taken up by the tumor. This percentage produces a cumulated activity of 35.63 +/- 8.40 MBq h and an equivalent dose per injected activity of 260 +/- 8.91 mSv/MBq. Pharmacokinetics and dosimetry of the 1887e(V)-DMSA complex indicate that this radiopharmaceutical could be evaluated in patients with soft tissue tumors, since the risk of radiation damage to the kidney or red bone marrow could not be an obstacle for its application in therapeutic nuclear medicine.