Piper nigrum extract suppresses tumor growth and enhances the antitumor immune response in murine models of breast cancer and melanoma.

Although the antitumor effect of P. nigrum has been widely studied, research related to its possible immunomodulatory effects is relatively scarce. Here, the antitumor and immunomodulatory activity of an ethanolic extract of P. nigrum were evaluated in the murine models of 4T1 breast cancer and B16-F10 melanoma. In vitro evaluations showed that the P. nigrum extract has cytotoxic activity, induces apoptotic cell death, and has a pro-oxidant effect in both cell lines, but it regulates glucose uptake differently in both lines, decreasing it in 4T1 but not in B16-F10. P. nigrum extract significantly reduced tumor size in both models and decreased the occurrence of macrometastases in 4T1 model. Evaluation of immune subpopulations by flow cytometry revealed that the P. nigrum extract significantly increases the frequency of dendritic cells and activated CD8+ T cells and decreases the frequency of myeloid-derived suppressor like cells and Tregs in the tumor microenvironment of both models but with different dynamics. Our findings strongly suggest that the P. nigrum extract exerts immunomodulatory functions, slightly related to the modulation of cellular energy metabolism, which could ultimately contribute to the promising antitumor effect of P. nigrum.

Natural Products Induce Different Anti-Tumor Immune Responses in Murine Models of 4T1 Mammary Carcinoma and B16-F10 Melanoma.

Natural products obtained from Petiveria alliacea (Anamu-SC) and Caesalpinia spinosa (P2Et) have been used for cancer treatment, but the mechanisms by which they exert their antitumor activity appear to be different. In the present work, we show that the Anamu-SC extract reduces tumor growth in the 4T1 murine mammary carcinoma model but not in the B16-F10 melanoma model, unlike the standardized P2Et extract. Both extracts decreased the levels of interleukin-10 (IL-10) in the B16-F10 model, but only P2Et increased the levels of tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ). Likewise, co-treatment of P2Et and doxorubicin (Dox) significantly reduced tumor size by 70% compared to the control group, but co-treatment of Anamu-SC with Dox had no additive effect. Analysis of intratumoral immune infiltrates showed that Anamu-SC decreased CD4+ T cell frequency more than P2Et but increased CD8+ T cell frequency more significantly. Both extracts reduced intratumoral monocytic myeloid-derived suppressor-like cell (M-MDSC-LC) migration, but the effect was lost when co-treated with doxorubicin. The use of P2Et alone or in co-treatment with Anamu-SC reduced the frequency of regulatory T cells and increased the CD8+/Treg ratio. In addition, Anamu-SC reduced glucose consumption in tumor cells, but this apparently has no effect on IFNγ- and TNFα-producing T cells, although it did reduce the frequency of IL-2-producing T cells. The efficacy of these herbal preparations is increasingly clear, as is the specificity conditioned by tumor heterogeneity as well as the different chemical complexity of each preparation. Although these results contribute to the understanding of specificity and its future benefits, they also underline the fact that the development of each of these standardized extracts called polymolecular drugs must follow a rigorous path to elucidate their biological activity.

Effect of Petiveria alliacea Extracts on Metabolism of K562 Myeloid Leukemia Cells.

Previously, studies have shown that leukemic cells exhibit elevated glycolytic metabolism and oxidative phosphorylation in comparison to hematopoietic stem cells. These metabolic processes play a crucial role in the growth and survival of leukemic cells. Due to the metabolic plasticity of tumor cells, the use of natural products has been proposed as a therapeutic alternative due to their ability to attack several targets in tumor cells, including those that could modulate metabolism. In this study, the potential of Petiveria alliacea to modulate the metabolism of K562 cell lysates was evaluated by non-targeted metabolomics. Initially, in vitro findings showed that P. alliacea reduces K562 cell proliferation; subsequently, alterations were observed in the endometabolome of cell lysates treated with the extract, mainly in glycolytic, phosphorylative, lipid, and amino acid metabolism. Finally, in vitro assays were performed, confirming that P. Alliacea extract decreased the oxygen consumption rate and intracellular ATP. These results suggest that the anti-tumor activity of the aqueous extract on the K562 cell line is attributed to the decrease in metabolites related to cell proliferation and/or growth, such as nucleotides and nucleosides, leading to cell cycle arrest. Our results provide a preliminary part of the mechanism for the anti-tumor and antiproliferative effects of P. alliacea on cancer.

Petiveria alliacea Reduces Tumor Burden and Metastasis and Regulates the Peripheral Immune Response in a Murine Myeloid Leukemia Model.

The poor response, adverse effects and drug resistance to treatment of acute myeloid leukemia (AML) have led to searching for safer and more effective therapeutic alternatives. We previously demonstrated that the alcoholic extract of Petiveria alliacea (Esperanza) has a significant in vitro antitumor effect on other tumor cells and also the ability to regulate energy metabolism. We evaluated the effect of the Esperanza extract in vitro and in vivo in a murine model of AML with DA-3/ER-GM cells. First, a chemical characterization of the extract was conducted through liquid and gas chromatography coupled with mass spectrometry. In vitro findings showed that the extract modulates tumor metabolism by decreasing glucose uptake and increasing reactive oxygen species, which leads to a reduction in cell proliferation. Then, to evaluate the effect of the extract in vivo, we standardized the mouse model by injecting DA-3/ER-GM cells intravenously. The animals treated with the extract showed a lower percentage of circulating blasts, higher values of hemoglobin, hematocrit, and platelets, less infiltration of blasts in the spleen, and greater production of cytokines compared to the control group. These results suggest that the antitumor activity of this extract on DA-3/ER-GM cells can be attributed to the decrease in glycolytic metabolism, its activity as a mitocan, and the possible immunomodulatory effect by reducing tumor proliferation and metastasis.

The delay in cell death caused by the induction of autophagy by P2Et extract is essential for the generation of immunogenic signals in melanoma cells.

P2Et extract obtained from the Caesalpinia spinosa plant is abundant in phenolic compounds such as gallic acid and ethyl gallate and can generate signals to activate the immune response by inducing a mechanism known as immunogenic cell death in murine models of breast cancer and melanoma. Immunogenic cell death involves mechanisms such as autophagy, which can be modulated by various natural compounds, including phenolic compounds with a structure similar to those found in P2Et extract. Here, we determine the role of autophagy in apoptosis and the generation of immunogenic signals using murine wild-type B16-F10 melanoma cells and cells with beclin-1 gene knockout. We show that P2Et extract and ethyl gallate induced autophagy, partially protecting tumor cells from death and promoting calreticulin exposure and the release of ATP. Although ethyl gallate showed a mechanism similar to that of P2Et, the induction of apoptosis and immunogenic signals was significantly weaker. In contrast, gallic acid-induced autophagy acted by blocking autophagic flux, which was associated with increased cell death. However, this compound did not induce any of the immunogenic death signals evaluated. Therefore, the complex extract has greater antitumor potential than isolated compounds. Here, we show that inducing autophagic flux with P2Et protects cancer cells from cell death and that this delay in cell death is required for the generation of immunogenic signals.

Bioactive Potential of Extracts of Labrenzia aggregata Strain USBA 371, a Halophilic Bacterium Isolated from a Terrestrial Source.

Previous studies revealed the potential of Labrenzia aggregata USBA 371 to produce cytotoxic metabolites. This study explores its metabolic diversity and compounds involved in its cytotoxic activity. Extracts from the extracellular fraction of strain USBA 371 showed high levels of cytotoxic activity associated with the production of diketopiperazines (DKPs). We purified two compounds and a mixture of two other compounds from this fraction. Their structures were characterized by 1D and 2D nuclear magnetic resonance (NMR). The purified compounds were evaluated for additional cytotoxic activities. Compound 1 (cyclo (l-Pro-l-Tyr)) showed cytotoxicity to the following cancer cell lines: breast cancer 4T1 (IC50 57.09 ± 2.11 µM), 4T1H17 (IC50 40.38 ± 1.94), MCF-7 (IC50 87.74 ± 2.32 µM), murine melanoma B16 (IC50 80.87 ± 3.67), human uterus sarcoma MES-SA/Dx5 P-pg (-) (IC50 291.32 ± 5.64) and MES-SA/Dx5 P-pg (+) (IC50 225.28 ± 1.23), and murine colon MCA 38 (IC50 29.85 ± 1.55). In order to elucidate the biosynthetic route of the production of DKPs and other secondary metabolites, we sequenced the genome of L. aggregata USBA 371. We found no evidence for biosynthetic pathways associated with cyclodipeptide synthases (CDPSs) or non-ribosomal peptides (NRPS), but based on proteogenomic analysis we suggest that they are produced by proteolytic enzymes. This is the first report in which the cytotoxic effect of cyclo (l-Pro-l-Tyr) produced by an organism of the genus Labrenzia has been evaluated against several cancer cell lines.

Assessment of Acute and Chronic Toxicity in Wistar Rats (Rattus norvegicus) and New Zealand Rabbits (Oryctolagus cuniculus) of an Enriched Polyphenol Extract Obtained from Caesalpinia spinosa.

Although herbal drugs are often considered safe for consumption, there is increasing evidence that some can generate undesirable health effects. However, polyphenols found in certain plants have been shown to provide a range of benefits for human health. In previous work, a standardized and quantified extract (P2Et) obtained from Caesalpinia spinosa (Dividivi) plant showed promising antioxidant, immunomodulatory, and anti-inflammatory properties in animal models of cancer and COVID-19 patients. The extract has also been subjected to genotoxicity, mutagenicity, and 28-day oral chronic toxicity evaluations, demonstrating a good safety profile. To advance preclinical and clinical development, further acute and chronic toxicity evaluations of the P2Et extract were performed. Acute toxicity tests were performed orally in Wistar rats at a dose of 2000 mg/kg, indicating that the lethal dose 50% (LD50) value exceeded 2000 mg/kg and classifying the P2Et extract as category 5 according to the Globally Harmonized System of Classification (GHS). In this work, chronic toxicity tests were conducted for 180 days on Wistar rats and New Zealand rabbits at a dose of 1000 mg/kg under Good Laboratory Practice (GLP) conditions. No weight loss or alterations in biochemical and hematological parameters associated with treatment were observed in the animals, suggesting the absence of toxicity in the assessed parameters. These results indicate that the P2Et extract is safe for oral administration at doses up to 1000 mg/kg body weight over a six-month period.

Plant extracts modulate cellular stress to inhibit replication of mouse Coronavirus MHV-A59.

The Covid-19 infection outbreak led to a global epidemic, and although several vaccines have been developed, the appearance of mutations has allowed the virus to evade the immune response. Added to this is the existing risk of the appearance of new emerging viruses. Therefore, it is necessary to explore novel antiviral therapies. Here, we investigate the potential in vitro of plant extracts to modulate cellular stress and inhibit murine hepatitis virus (MHV)-A59 replication. L929 cells were treated with P2Et (Caesalpinia spinosa) and Anamu SC (Petiveria alliacea) plant extracts during infection and virus production, ROS (reactive oxygen species), UPR (unfolded protein response), and autophagy were assessed. P2Et inhibited virus replication and attenuated both ROS production and UPR activation induced during infection. In contrast, the sustained presence of Anamu SC during viral adsorption and replication was required to inhibit viral infection, tending to induce pro-oxidant effects, and increasing UPR gene expression. Notably, the loss of the PERK protein resulted in a slight decrease in virus yield, suggesting a potential involvement of this UPR pathway during replication. Intriguingly, both extracts either maintained or increased the calreticulin surface exposure induced during infection. In conclusion, our findings highlight the development of antiviral natural plant extracts that differentially modulate cellular stress.

Gallotannin-rich Caesalpinia spinosa fraction decreases the primary tumor and factors associated with poor prognosis in a murine breast cancer model.

BACKGROUND: Several treatment alternatives are available for primary breast cancer, although those for metastatic disease or inflammation associated with tumor progression are ineffective. Therefore, there is a great need for new therapeutic alternatives capable of generating an immune response against residual tumor cells, thus contributing to eradication of micrometastases and cancer stem cells. The use of complex natural products is an excellent therapeutic alternative widely used by Chinese, Hindu, Egyptian, and ancestral Latin-American Indian populations. METHODS: The present study evaluated cytotoxic, antitumor, and tumor progression activities of a gallotannin-rich fraction derived from Caesalpinia spinosa (P2Et). The parameters evaluated in vitro were mitochondrial membrane depolarization, phosphatidylserine externalization, caspase 3 activation, DNA fragmentation, and clonogenic activity. The parameters evaluated in vivo were tumor growth, leukocyte number, metastatic cell number, and cytokine production by flow cytometry. RESULTS: The in vitro results showed that the P2Et fraction induced apoptosis with mitochondrial membrane potential loss, phosphatidylserine externalization, caspase 3 activation, DNA fragmentation, and decreased clonogenic capacity of 4T1 cells. In vivo, the P2Et fraction induced primary tumor reduction in terms of diameter and weight in BALB/c mice transplanted with 4T1 cells and decreased numbers of metastatic cells, mainly in the spleen. Furthermore, decreases in the number of peripheral blood leukocytes (leukemoid reaction) and interleukin 6 (IL-6) serum levels were found, which are events associated with a poor prognosis. The P2Et fraction exerts its activity on the primary tumor, reduces cell migration to distant organs, and decreases IL-6 serum levels, implying tumor microenvironment mechanisms. CONCLUSIONS: Overall, the P2Et fraction lessens risk factors associated with tumor progression and diminishes primary tumor size, showing good potential for use as an adjuvant in breast cancer ER(+) treatment.

Modulation of Myeloid-Derived Suppressor Cells in the Tumor Microenvironment by Natural Products.

During carcinogenesis, the microenvironment plays a fundamental role in tumor progression and resistance. This tumor microenvironment (TME) is characterized by being highly immunosuppressive in most cases, which makes it an important target for the development of new therapies. One of the most important groups of cells that orchestrate immunosuppression in TME is myeloid-derived suppressor cells (MDSCs), which have multiple mechanisms to suppress the immune response mediated by T lymphocytes and thus protect the tumor. In this review, we will discuss the importance of modulating MDSCs as a therapeutic target and how the use of natural products, due to their multiple mechanisms of action, can be a key alternative for modulating these cells and thus improve response to therapy in cancer patients.

Plant-derived extracts and metabolic modulation in leukemia: a promising approach to overcome treatment resistance.

Leukemic cells acquire complex and often multifactorial mechanisms of resistance to treatment, including various metabolic alterations. Although the use of metabolic modulators has been proposed for several decades, their use in clinical practice has not been established. Natural products, the so-called botanical drugs, are capable of regulating tumor metabolism, particularly in hematopoietic tumors, which could partly explain the biological activity attributed to them for a long time. This review addresses the most recent findings relating to metabolic reprogramming-Mainly in the glycolytic pathway and mitochondrial activity-Of leukemic cells and its role in the generation of resistance to conventional treatments, the modulation of the tumor microenvironment, and the evasion of immune response. In turn, it describes how the modulation of metabolism by plant-derived extracts can counteract resistance to chemotherapy in this tumor model and contribute to the activation of the antitumor immune system.

Safety and efficacy of P2Et extract from Caesalpinia spinosa in breast cancer patients: study protocol for a randomized double blind phase II clinical trial (CS003-BC).

BACKGROUND: Chemotherapy in breast cancer is effective but can generate significant toxicity and lead to tumor resistance. Joint treatment with standardized plant extracts can be an alternative to improve the response and allow an effective activation of the antitumor immune response that favors recovery in the short and long term. The P2Et extract of Caesalpinia spinosa presents antitumor activity in cells and animal models of breast cancer, improves the tumor microenvironment, and induces activation of the specific immune response against the tumor and is synergistic when used together with anthracyclines, which makes it a good candidate for evaluation in patients. METHODS: Conducted at a single center, this phase II study is a randomized, double-blind, placebo-controlled trial aimed at assessing the safety and efficacy of P2Et extract in patients diagnosed with stage II and III breast cancer, who are eligible for neoadjuvant treatment. The study aims to determine the safety profile at the previously established optimal biological dose from phase I trial while investigating various efficacy outcomes. These outcomes include improvements in quality of life, immunomodulation, metabolic profile, microbiome, as well as clinical indicators such as tumor reduction, disease-free survival, and pathological response, assessed at different stages of the treatment regimen. DISCUSSION: Treatment with the P2Et extract in breast cancer patients is hypothesized to enhance overall well-being, positively influencing their quality of life, while also triggering an antitumor immune response and enhancing immune infiltration. These combined effects have the potential to contribute to improved long-term survival outcomes for patients receiving the phytomedicine alongside neoadjuvant chemotherapy treatment. TRIAL REGISTRATION: This trial was registered in the US National Library of Medicine with identifier NCT05007444. First Registered August 16th, 2021. Last Updated: August 9th, 2022.

Plant extract from Caesalpinia spinosa inhibits cancer-associated fibroblast-like cells generation and function in a tumor microenvironment model.

Interactions in the tumor microenvironment (TME) between tumor cells and stromal cells such as cancer-associated fibroblasts (CAF) favor increased survival, progression, and transformation of cancer cells by activating mechanisms of invasion and metastasis. The design of new therapies to modulate or eliminate the CAF phenotype or functionality has been the subject of recent research including natural product-based therapies. We have previously described the generation of a standardized extract rich in polyphenols obtained from the Caesalpinia spinosa plant (P2Et), which present antitumor activities in breast cancer and melanoma models through activities that modulate the metabolism of tumor cells or induce the development of the immune response. In this work, a model of CAF generation was initially developed from the exposure of 3T3 fibroblasts to the cytokine TGFß1. CAF-like cells generated in this way exhibited changes in the expression of Caveolin-1 and α-SMA, and alterations in glucose metabolism and redox status, typical of CAFs isolated from tumor tissues. Then, P2Et was shown to counteract in vitro-induced CAF-like cell generation, preventing caveolin-1 loss and attenuating changes in glucose uptake and redox profile. This protective effect of P2Et translates into a decrease in the functional ability of CAFs to support colony formation and migration of 4T1 murine breast cancer tumor cells. In addition to the functional interference, the P2Et extract also decreased the expression of genes associated with the epithelial-mesenchymal transition (EMT) and functional activities related to the modulation of the cancer stem cells (CSC) population. This work is an in vitro approach to evaluate natural extracts' effect on the interaction between CAF and tumor cells in the tumor microenvironment; thus, these results open the chance to design a more profound and mechanistic analysis to explore the molecular mechanisms of P2Et multimolecular activity and extent this analysis to an in vivo perspective. In summary, we present here a standardized polymolecular natural extract that has the potential to act in the TME by interfering with CAF generation and functionality.

IL-8 in bone marrow and peripheral blood of patients with B-cell acute lymphoblastic leukemia is associated with high regulatory T cell counts, degree of tumor infiltration and expression of CXCR1 in blasts.

INTRODUCTION: Regulatory T cells (Treg cells) in a tumor environment and the expression of forkhead box P3 (FOXP3) in tumor cells have been associated with a poor prognosis. There are few studies evaluating Treg cells and FOXP3 in B-cell acute lymphoblastic leukemia (B-cell ALL). This study aimed to evaluate the frequencies of Treg cells in bone marrow (BM) and peripheral blood (PB) of patients with B-cell ALL and to determine their associations with the circulating cytokine profile and the expression of CXCR1 (IL-8 receptor) in Treg cells, as well as to compare FOXP3 expression in blasts of patients with B-cell ALL and normal lymphoid precursors. METHODS: Samples of BM and PB from patients with B-cell ALL and healthy controls were studied. Treg cells, cytokines, FOXP3 and CXCR1 were evaluated using flow cytometry and analyzed. RESULTS: A total of 20 patients with B-cell ALL and 10 healthy controls were included. In B-cell ALL patients, Treg cell frequencies increased significantly, with higher percentages in the PB. Absolute Treg cell counts were associated with absolute blast counts in the BM and PB and with an IL-8 concentration. The IL-8 and IL-6 levels were associated with the CXCR1 expression in PB Treg cells. In addition, a greater expression of FOXP3 was observed in leukemic blasts than in normal lymphoid precursors. CONCLUSIONS: These results suggest that the presence of Treg cells and cytokines in the tumor environment may correspond to mechanisms to evade the immune response. For that reason, it would be important to monitor these parameters in B-cell ALL to establish their effect on the disease prognosis.

Doxorubicin Activity Is Modulated by Traditional Herbal Extracts in a 2D and 3D Multicellular Sphere Model of Leukemia.

The modulation of the tumor microenvironment by natural products may play a significant role in the response of tumor cells to chemotherapy. In this study, we evaluated the effect of extracts derived from P2Et (Caesalpinia spinosa) and Anamú-SC (Petiveria alliacea) plants, previously studied by our group, on the viability and ROS levels in the K562 cell line (Pgp- and Pgp+), endothelial cells (ECs, Eahy.926 cell line) and mesenchymal stem cells (MSC) cultured in 2D and 3D. The results show that: (a) the two botanical extracts are selective on tumor cells compared to doxorubicin (DX), (b) cytotoxicity is independent of the modulation of intracellular ROS for plant extracts, unlike DX, (c) the interaction with DX can be influenced by chemical complexity and the expression of Pgp, (d) the 3D culture shows a greater sensitivity of the tumor cells to chemotherapy, in co-treatment with the extracts. In conclusion, the effect of the extracts on the viability of leukemia cells was modified in multicellular spheroids with MSC and EC, suggesting that the in vitro evaluation of these interactions can contribute to the comprehension of the pharmacodynamics of the botanical drugs.

Exploring the safety and efficacy of phytomedicine Petiveria alliacea extract (Esperanza) in patients with metastatic gastrointestinal tumors and acute leukemias: study protocol for a phase Ib/randomized double blind phase II trial (PA001).

BACKGROUND: The energy metabolism of drug-resistant tumor cells can provide a survival advantage during therapy, and treatment itself may influence metabolic reprogramming. Petiveria alliacea (Traditional name: Anamu) could inhibit glycolysis and OXPHOX modulating tumor metabolism, making it a potential treatment for tumors with altered metabolism. This clinical study aims to evaluate the safety and efficacy of a standardized Anamu phytomedicine called Esperanza in treating gastric tumors and acute leukemias. METHODS: This is a prospective, open label, phase I/ randomized, double-blind single-center phase II study designed to evaluate the safety and efficacy of Esperanza extract in patients with metastatic gastrointestinal tumors and acute leukemias. In stage 1, the study will determine the MTD and assess safety. In stage 2, safety at the MTD will be evaluated, and the efficacy of Esperanza extract will be explored in both metastatic gastric tumors and acute leukemias. Quality of life improvement will be the primary outcome in the gastric tumor group, while different efficacy outcomes will be assessed in the acute leukemia group. A placebo group will be used for comparison in the gastric tumor group, and a historical control group will be used in the acute leukemia arm. DISCUSSION: This clinical trial aims to evaluate the safety profile of the Esperanza extract in patients with metastatic gastrointestinal tumors and acute leukemias, while exploring its potential efficacy in conjunction with standard treatment for these pathologies. TRIAL REGISTRATION: This trial was registered in the US National Library of Medicine with identifier NCT05587088. Registered October 19th, 2022.

Encapsulated Phytomedicines against Cancer: Overcoming the "Valley of Death".

P2Et is the standardized extract of Caesalpinia spinosa (C. spinosa), which has shown the ability to reduce primary tumors and metastasis in animal models of cancer, by mechanisms involving the increase in intracellular Ca++, reticulum stress, induction of autophagy, and subsequent activation of the immune system. Although P2Et has been shown to be safe in healthy individuals, the biological activity and bioavailability can be increased by improving the dosage form. This study investigates the potential of a casein nanoparticle for oral administration of P2Et and its impact on treatment efficacy in a mouse model of breast cancer with orthotopically transplanted 4T1 cells. Animals were treated with either free or encapsulated oral P2Et orally or i.p. Tumor growth and macrometastases were evaluated. All P2Et treatments significantly delayed tumor growth. The frequency of macrometastasis was reduced by 1.1 times with P2Et i.p., while oral P2Et reduced it by 3.2 times and nanoencapsulation reduced it by 3.57 times. This suggests that nanoencapsulation led to higher doses of effective P2Et being delivered, slightly improving bioavailability and biological activity. Therefore, the results of this study provide evidence to consider P2Et as a potential adjuvant in the treatment of cancer, while the nanoencapsulation of P2Et provides a novel perspective on the delivery of these functional ingredients.

Untargeted metabolomic and lipidomic analyses reveal lipid dysregulation in the plasma of acute leukemia patients.

Acute leukemias (AL) are aggressive neoplasms with high mortality rates. Metabolomics and oxidative status have emerged as important tools to identify new biomarkers with clinical utility. To identify the metabolic differences between healthy individuals (HI) and patients with AL, a multiplatform untargeted metabolomic and lipidomic approach was conducted using liquid and gas chromatography coupled with quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS or GC-QTOF-MS). Additionally, the total antioxidant capacity (TAC) was measured. A total of 20 peripheral blood plasma samples were obtained from patients with AL and 18 samples from HI. Our analysis revealed 135 differentially altered metabolites in the patients belonging to 12 chemical classes; likewise, the metabolic pathways of glycerolipids and sphingolipids were the most affected in the patients. A decrease in the TAC of the patients with respect to the HI was evident. This study conducted with a cohort of Colombian patients is consistent with observations from other research studies that suggest dysregulation of lipid compounds. Furthermore, metabolic differences between patients and HI appear to be independent of lifestyle, race, or geographic location, providing valuable information for future advancements in understanding the disease and developing more global therapies.

A gallotannin-rich fraction from Caesalpinia spinosa (Molina) Kuntze displays cytotoxic activity and raises sensitivity to doxorubicin in a leukemia cell line.

BACKGROUND: Enhancement of tumor cell sensitivity may help facilitate a reduction in drug dosage using conventional chemotherapies. Consequently, it is worthwhile to search for adjuvants with the potential of increasing chemotherapeutic drug effectiveness and improving patient quality of life. Natural products are a very good source of such adjuvants. METHODS: The biological activity of a fraction enriched in hydrolysable polyphenols (P2Et) obtained from Caesalpinia spinosa was evaluated using the hematopoietic cell line K562. This fraction was tested alone or in combination with the conventional chemotherapeutic drugs doxorubicin, vincristine, etoposide, camptothecin and taxol. The parameters evaluated were mitochondrial depolarization, caspase 3 activation, chromatin condensation and clonogenic activity. RESULTS: We found that the P2Et fraction induced mitochondrial depolarization, activated caspase 3, induced chromatin condensation and decreased the clonogenic capacity of the K562 cell line. When the P2Et fraction was used in combination with chemotherapeutic drugs at sub-lethal concentrations, a fourfold reduction in doxorubicin inhibitory concentration 50 (IC50) was seen in the K562 cell line. This finding suggested that P2Et fraction activity is specific for the molecular target of doxorubicin. CONCLUSIONS: Our results suggest that a natural fraction extracted from Caesalpinia spinosa in combination with conventional chemotherapy in combination with natural products on leukemia cells may increase therapeutic effectiveness in relation to leukemia.

The breast cancer immune microenvironment is modified by neoadjuvant chemotherapy.

Neoadjuvant chemotherapy (NAT) in breast cancer (BC) has been used to reduce tumor burden prior to surgery. However, the impact on prognosis depends on the establishment of Pathological Complete Response (pCR), which is influenced by tumor-infiltrating lymphocyte levels and the activation of the antitumor immune response. Nonetheless, NAT can affect immune infiltration and the quality of the response. Here, we showed that NAT induces dynamic changes in the tumor microenvironment (TME). After NAT, an increase of regulatory T cells and a decrease of CD8+ T cells was found in tumor, correlated with the presence of metastatic cells in lymph nodes. In addition, an increase of polymorphonuclear myeloid-derived suppressor like cells was found in luminal patients post-NAT. pCR patients showed a balance between the immune populations, while non-pCR patients presented an inverse relationship in the frequency of CD68+ versus CD3+, CD8+, and CD20+ cells. Moreover, activated T cells were found in peripheral blood, as well as an increase in T cell clonality with a lower diversity post-NAT. Overall, these results shown that NAT induces an activation of immune response, however, a balance in the TME seems to be related to a better antigenic presentation and therefore a better response to treatment.