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-ß, 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-ß, 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.

Tumour growth inhibitory effect of Ibervillea sonorae phytopreparations in cervical cancer xenografts.

Cucurbitacin IIb, a triterpene obtained from the Ibervillea sonorae plant, reduces tumour development in a preclinical model of cervical cancer. Acetison and Etanison, phytopreparations made from I. sonorae, present biological activity analogous to CIIb in HeLa. This research evaluated the tumour growth inhibitory effect of these phytopreparations in a HeLa xenograft tumour model in BALB/c nude mice. Tumours in mice were treated every 3 days for 12 days with cisplatin (2 mg/kg), CIIb (5 mg/kg), Acetison (20 mg/kg), Etanison (30 mg/kg), and DMSO at 2%. For histological observations, tumours were stained with H&E. Fingerprinting of both phytopreparations was performed using HPLC-UV and UHPLC-APCI-IT-MS. Both phytopreparations and CIIb inhibit tumour development as well as Cisplatin (75.5%); Etanison (77.7%), Acetison (73.6%), and CIIb (73.0%). Furthermore, only tumours treated with cisplatin showed invasion of bone tissue. The results show the potential use of I. sonorae phytopreparations in the treatment of cervical cancer.

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.

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.

[Stem cells: searching predisposition to cardiac commitment by surface markers expression]. / Células madre: buscando marcadores de superficie celular que predispongan compromiso de diferenciación cardiaca.

It is well-known that cardiovascular diseases are the leading cause of death worldwide, and represent an important economic burden to health systems. In an attempt to solve this problem, stem cell therapy has emerged as a therapeutic option. Within the last 20 years, a great variety of stem cells have been used in different myocardial infarction models. Up until now, the use of cardiac stem cells (CSCs) has seemed to be the best option, but the inaccessibility and scarcity of these cells make their use unreliable. Additionally, there is a high risk as they have to be obtained directly from the heart of the patient. Unlike CSCs, adult stem cells originating from bone marrow or adipose tissue, among others, appear to be an attractive option due to their easier accessibility and abundance, but particularly due to the probable existence of cardiac progenitors among their different sub-populations. In this review an analysis is made of the surface markers present in CSCs compared with other adult stem cells. This suggested the pre-existence of cells sharing specific surface markers with CSCs, a predictable immunophenotype present in some cells, although in low proportions, and with a potential of cardiac differentiation that could be similar to CSCs, thus increasing their therapeutic value. This study highlights new perspectives regarding MSCs that would enable some of these sub-populations to be differentiated at cardiac tissue level.

Células madre: buscando marcadores de superficie celular que predispongan compromiso de diferenciación cardiaca / Stem cells: searching predisposition to cardiac commitment by surface markers expression

Resumen Actualmente las enfermedades cardiovasculares se han convertido en un serio problema para los sistemas de salud de todo el mundo, ya que son la principal causa de muerte y representan una enorme carga económica. Este problema ha sido abordado con diferentes estrategias, entre ellas con la ayuda de terapia celular, aunque sin resultados contundentes. Durante más de 20 años, se ha utilizado una gran variedad de células madre en diferentes modelos de infarto del miocardio. El uso de células madre cardiacas (CSC) parece ser la mejor opción, pero la inaccesibilidad y la escasez de estas células hacen que su uso sea muy limitado. Además, existe un riesgo elevado pues tienen que obtenerse directamente del corazón del paciente. A diferencia de las CSC, las células madre adultas derivadas de médula ósea o tejido adiposo, entre otras, representan una opción atractiva debido a su fácil accesibilidad y abundancia, pero sobre todo a la probable existencia de progenitores cardiacos entre sus diferentes subpoblaciones. En esta revisión hacemos un análisis de los marcadores de superficie presentes en CSC en comparación con otras células madre adultas, y sugerimos la preexistencia de células que comparten marcadores de superficie específicos con CSC, la presencia de un inmunofenotipo predecible, aunque en proporciones bajas, pero con un potencial de diferenciación cardiaca similar a las CSC, lo cual podría aumentar su valor terapéutico. Este estudio revela las nuevas perspectivas con respecto a la presencia de dichos marcadores, los cuales comprometerían algunas de estas subpoblaciones a diferenciarse a tejido cardiaco.

Abstract It is well-known that cardiovascular diseases are the leading cause of death world- wide, and represent an important economic burden to health systems. In an attempt to solve this problem, stem cell therapy has emerged as a therapeutic option. Within the last 20 years, a great variety of stem cells have been used in different myocardial infarction models. Up until now, the use of cardiac stem cells (CSCs) has seemed to be the best option, but the inaccessibility and scarcity of these cells make their use unreliable. Additionally, there is a high risk as they have to be obtained directly from the heart of the patient. Unlike CSCs, adult stem cells originating from bone marrow or adipose tissue, among others, appear to be an attractive option due to their easier accessibility and abundance, but particularly due to the probable existence of cardiac progenitors among their different sub-populations. In this review an analysis is made of the surface markers present in CSCs compared with other adult stem cells. This suggested the pre-existence of cells sharing specific surface markers with CSCs, a predictable immunophenotype present in some cells, although in low proportions, and with a potential of cardiac differentiation that could be similar to CSCs, thus increasing their therapeutic value. This study highlights new perspectives regarding MSCs that would enable some of these sub-populations to be differentiated at cardiac tissue level.