Percorrer por autor "Pereira, Joana M."
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- Achillea millefolium L. hydroethanolic extract inhibits growth of human tumor cell lines by interfering with cell cycle and inducing apoptosisPublication . Pereira, Joana M.; Peixoto, Vanessa; Teixeira, Alexandra Margarida; Sousa, Diana; Barros, Lillian; Ferreira, Isabel C.F.R.; Vasconcelos, M. Helena
- An aqueous extract of tuberaria lignosa inhibits cell growth, alters the cell cycle profile, and induces apoptosis of NCI-H460 tumor cellsPublication . Pereira, Joana M.; Lopes-Rodrigues, Vanessa; Xavier, Cristina; Lima, M. João; Lima, Raquel T.; Ferreira, Isabel C.F.R.; Vasconcelos, M. HelenaTuberaria lignosa (Sweet) Samp. is found in European regions, and has antioxidant properties due to its composition in ascorbic acid and phenolic compounds. Given its traditional use and antioxidant properties, the tumor cell growth inhibitory potential of aqueous extracts from T. lignosa (prepared by infusion and decoction) was investigated in three human tumor cell lines: MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), and HCT-15 (human colorectal adenocarcinoma). Both extracts inhibited the growth of these cell lines; the most potent one being the T. lignosa extract obtained by infusion in the NCI-H460 cells (GI50 of approximately 50 μg/mL). Further assays were carried out with this extract in NCI-H460 cells. At 100 μg/mL or 150 μg/mL it caused an increase in the percentage of cells in the G0/G1 phase and a decrease of cells in S phase of the cell cycle. Additionally, these concentrations caused an increase in the percentage of apoptotic cells. In agreement, a decrease in total poly (ADP-ribose) polymerase (PARP) and pro-caspase 3 levels was found. In conclusion, the T. lignosa extract obtained by infusion was more potent in NCI-H460 cells, altering the cell cycle progression and inducing apoptosis. This work highlights the importance of T. lignosa as a source of bioactive compounds with tumor cell growth inhibitory potential.
- Cell growth inhibitory effect of an aqueous extract of Achillea millefolium in human tumor cell linesPublication . Pereira, Joana M.; Peixoto, Vanessa; Teixeira, Alexandra Margarida; Sousa, Diana; Ferreira, Isabel C.F.R.; Vasconcelos, M. HelenaPlants used in folk medicine have increased importance in the pharmaceutical field. Achillea millefolium, also known as yarrow, is a traditional plant that can be found in Europe, Asia, North Africa and North America [1, 2]. Yarrow was shown to have antitumour, antimicrobial, antiinflammatory and antioxidant properties [3]. Indeed, several studies indicated that this plant has antioxidant potential due to its chemical composition in phenolic acids and flavones [3]. The aim of this work was to study if an aqueous extract of A. millefolium presents cell growth inhibitory activity in three human tumor cell lines: non-small cell lung cancer (NCI-H460), human colorectal adenocarcinoma (HCT-15) and breast adenocarcinoma (MCF-7). Sulforhodamine B assay was carried out to determine in which cells the extract was more potent. In addition, the effect of the aqueous extract on NCI-H460 cell cycle profile and programmed cell death was analyzed by flow cytometry following incubation with propidium iodide (PI) or Annexin V-FICT/PI staining, respectively. Results showed that A. millefolium extract inhibited the growth of the mentioned cell lines. Moreover, further studies of this extract in NCI-H460 cells indicated that the reduction in cell growth was due to alterations in cell cycle profile and in apoptosis. Future work will also include analysis of protein expression by Western Blot to further unravel the mechanism of action of this extract.
- Investigating the cell growth inhibitory effect of flower extracts of Sambucus nigra L. in human tumour cell linesPublication . Lima, M. João; Pereira, Joana M.; Lima, Raquel T.; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.; Vasconcelos, M. HelenaSambucus nigra L. (elder) is widely used in traditional medicine, especially for its diuretic, antiinflammatory, diaphoretic and expectorant properties. Its rich flavonoids and ascorbic acid contents makes S. nigra flowers a good source of antioxidant compounds [1]. Nonetheless, the tumor cell growth inhibitory activity of such plant material has never been studied. Therefore, the aim of this ongoing project is to investigate if the flower extracts of S. nigra have cell growth inhibitory activity in various human tumor cell lines. The flower extracts were obtained by infusion, methanol extraction, methanol:water (80:20, v:v) extraction or by decoction. These specimens were processed in order to be lyophilized and extracted. Stock solutions of all extracts were prepared in DMSO at a maximum concentration of 100 mg/mL and further stored at -20 ºC. Such extracts were screened for tumor cell growth inhibitory activity in three human tumor cell lines: NCI-H460 (non-small cell lung cancer), A375-C5 (melanoma) and MCF-7 (breast adenocarcinoma). The cell growth assay performed was the Sulforhodamine B assay, during which cells were treated for 48 hours with 100 μL of six serial dilutions of each extract, ranging from 25 μg/mL to 400 μg/mL. Doxorubicin was used as a positive control of tumor cell growth inhibition, at a maximum concentration of 150 nM. The effect of the solvent of the extracts (DMSO) on the growth of the cell lines was also evaluated, by treating cells with the maximum concentration of DMSO used (0.20 %). Some of the extracts showed no tumor cell growth inhibitory activity up to the highest concentration tested, whereas other extracts have some tumor cell growth inhibitory potential. However, those extracts showed different activity over time, indicating possible lack of stability. The results will be confirmed with fresh aliquots of those extracts. The most potent extract will then be selected to be further studied in the most sensitive cell line. Such studies will consist in investigating its antiproliferative potential, the effect on cell cycle profile and on programmed cell death.
- Melissa officinalis L. ethanolic extract inhibits the growth of a lung cancer cell line by interfering with the cell cycle and inducing apoptosisPublication . Magalhães, Daniela B.; Castro, Inês; Lopes-Rodrigues, Vanessa; Pereira, Joana M.; Barros, Lillian; Ferreira, Isabel C.F.R.; Xavier, Cristina; Vasconcelos, M. HelenaMelissa officinalis is a plant from the family Lamiaceae, native in Europe particularly in the Mediterranean region. Given our interest in identifying extracts and compounds capable of inhibiting tumor cell growth, and given the antioxidant content and the high consumption of Melissa officinalis in Portugal, this study aimed to test the tumor cell growth inhibitory activity of five different extracts of this plant (aqueous, methanolic, ethanolic, hydromethanolic and hydroethanolic) in three human tumor cell lines: MCF-7, AGS and NCI-H460. All extracts decreased cell growth in all cell lines in a concentration-dependent manner. The ethanolic extract was the most potent one, presenting a GI50 concentration of approximately 100.9 μg mL−1 in the NCI-H460 lung cancer cells. This extract was characterized by LC-DAD-ESI/MS regarding its phenolic composition, revealing rosmarinic acid as the most abundant compound. The GI75 concentration of this extract affected the cell cycle profile of these cells. In addition, both the GI50 and the GI75 concentrations of the extract induced cellular apoptosis. Moreover, treatment of NCI-H460 cells with this extract caused a decrease in pro-caspase 3 and an increase in p53 levels. This study emphasizes the relevance of the study of natural products as inhibitors of tumor cell growth.
- Study of the mechanism of action of Melissa officinalis L. extracts in inhibiting the growth of human tumor cellular linesPublication . Magalhães, Daniela B.; Castro, Inês; Pereira, Joana M.; Lopes-Rodrigues, Vanessa; Ferreira, Isabel C.F.R.; Xavier, Cristina; Vasconcelos, M. HelenaMelissa officinalis L., commonly known as "lemon balm" is a perianal herbaceous plant from the family Laminaceae, native in Europe particularly in the Mediterranean region. Rosmarinic acid, the most abundant phenolic compound derived from caffeic acid, and some flavonoids such as luteolin-7-O-glucoside are described as responsible for its antimicrobial properties, antiinflammatory, antioxidant and even anti-tumor activities. Previous studies have investigated the antitumor effects of M. officinalis extracts, including aqueous, ethanolic and hydro-alcoholic extracts, in various human tumor cell lines. However, to our knowledge, the mechanism of action of the extracts has never been investigated. Therefore, the aims of this project are to: i) investigate if 5 different extracts of Melissa officinalis, prepared with different extraction methods, have cell growth inhibitory activity in three human tumor cell lines: NCI-H460 (non-small cell lung cancer), MCF-7 (breast adenocarcinoma) and AGS (gastric adenocarcinoma) and ii) study the mechanism of action of the most potent extract. Results showed that all the extracts decreased cell growth in all tumor cell lines, in a concentration-dependent manner. The ethanolic extract was the most potent one, presenting a 50% growth inhibition concentration (GI50) of approximately 100.9 μg/mL in the NCI-H460 cells (most sensitive cell line). Current work is confirming the effect of this extract on cell cycle and apoptosis.
- The cell growth inhibitory effect of an aqueous extract of Tuberaria lignosa in NCI-H460 human tumor cellsPublication . Pereira, Joana M.; Rodrigues, V.L.; Xavier, Cristina; Lima, M. João; Lima, Raquel T.; Ferreira, Isabel C.F.R.; Vasconcelos, M. HelenaTuberaria lignosa (Sweet) Samp. is found in European regions. This plant has antioxidant properties due to its composition in ascorbic acid and phenolic compounds [1]. Given its antioxidant properties and its large traditional use, the aim of this work was to study the tumor cell growth inhibitory potential of aqueous extracts from T. lignosa (prepared by infusion and decoction). Cell growth was accessed by the Sulforhodamine B (SRB) assay in three human tumor cell lines: MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), and HCT-15 (human colorectal adenocarcinoma). Both extracts inhibited the growth of the cell lines tested. The most potent extract was the T. lignosa extract obtained by infusion, in the NCI-H460 cells (presenting a GI50 of approximately 50 μg/mL). Further assays were carried out with two different concentrations of this extract in the NCI-H460 cells. The determination of its effect on the cell cycle profile was carried out by analyzing cellular DNA content by flow cytometry following incubation with propidium iodide. Determination of cellular apoptosis was performed with the Annexin V-FICT and propidium iodide assay, by flow cytometry. The expression of apoptotic proteins was carried out by Western Blot. Results showed that 100 μg/mL or 150 μg/mL of extract caused an increase in the percentage of cells in the G0/G1 phase and a decrease of cells in S phase of the cell cycle. In addition, the extract caused an increase in the percentage of apoptotic cells, with a decrease in total poly (ADP-ribose) polymerase (PARP) and pro-caspase 3 levels. In conclusion, the T. lignosa extract obtained by infusion was more potent in NCI-H460 cells, altering the cell cycle progression and inducing apoptosis.