Immunotherapy for Pediatric Gliomas: CAR-T Cells Against B7H3: A Review of the Literature.

BACKGROUND: B7H3 is a co-stimulatory molecule for immune reactions found on the surface of tumor cells in a wide variety of tumors. Preclinical and clinical studies have reported it as a tumor target towards which various immunotherapy modalities could be directed. So far, good results have been obtained in hematological neoplasms; however, a contrasting situation is evident in solid tumors, including those of the CNS, which show high refractoriness to current treatments. The appearance of cellular immunotherapies has transformed oncology due to the reinforcement of the immune response that is compromised in people with cancer. OBJECTIVE: This article aims to review the literature to describe the advancement in knowledge on B7H3 as a target of CAR-T cells in pediatric gliomas to consider them as an alternative in the treatment of these patients. RESULTS: Although B7H3 is considered a suitable candidate as a target agent for various immunotherapy techniques, there are still limitations in using CAR-T cells to achieve the desired success. CONCLUSION: Results obtained with CAR-T cells can be further improved by the suggested proposals; therefore, more clinical trials are needed to study this new therapy in children with gliomas.

National Burden and Trends for 29 Groups of Cancer in Mexico from 1990 to 2019: A Secondary Analysis of the Global Burden of Disease Study 2019.

The global burden of cancer is on the rise, with varying national patterns. To gain a better understanding and control of cancer, it is essential to provide national estimates. Therefore, we present a comparative description of cancer incidence and mortality rates in Mexico from 1990 to 2019, by age and sex for 29 different cancer groups. Based on public data from the Global Burden of Disease Study 2019, we evaluated the national burden of cancer by analyzing counts and crude and age-standardized rates per 100,000 people with 95% uncertainty intervals for 2019 and trends using the annual percentage change from 1990 to 2019. In 2019, cancer resulted in 222,060 incident cases and 105,591 deaths. In 2019, the highest incidence of cancer was observed in non-melanoma skin cancer, prostate cancer, and breast cancer. Additionally, 53% of deaths were attributed to six cancer groups (lung, colorectal, stomach, prostate, breast, and pancreatic). From 1990 to 2019, there was an increasing trend in incidence and mortality rates, which varied by 10-436% among cancer groups. Furthermore, there were cancer-specific sex differences in crude and age-standardized rates. The results show an increase in the national cancer burden with sex-specific patterns of change. These findings can guide national efforts to reduce health loss due to cancer.

Biochemical and molecular modulation of CCl4-induced peripheral and central damage by Tilia americana var. mexicanaextracts.

Around the world, species from the genus Tilia are commonly used because of their peripheral and central medicinal effects; they are prepared as teas and used as tranquilizing, anticonvulsant, and analgesic agents. In this study, we provide evidence of the protective effects of organic and aqueous extracts (100 mg/kg, i.p.) obtained from the leaves of Tilia americana var. mexicana on CCl4-induced liver and brain damage in the rat. Protection was observed in the liver and brain (cerebellum, cortex and cerebral hemispheres) by measuring the activity of antioxidant enzymes and levels of malondialdehyde (MDA) using spectrophotometric methods. Biochemical parameters were also assessed in serum samples from the CCl4-treated rats. The T. americana var. mexicana leaf extracts provided significant protection against CCl4-induced peripheral and central damage by increasing the activity of antioxidant enzymes, diminishing lipid peroxidation, and preventing alterations in biochemical serum parameters, such as the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), γ-globulin (γ-GLOB), serum albumin (ALB), total bilirubin (BB), creatinine (CREA) and creatine kinase (CK), relative to the control group. Additionally, we correlated gene expression with antioxidant activity in the experimental groups treated with the organic and aqueous Tilia extracts and observed a non-statistically significant positive correlation. Our results provide evidence of the underlying biomedical properties of T. americana var. mexicana that confer its neuro- and hepatoprotective effects.

Toxicological evaluation of the natural products and some semisynthetic derivatives of Heterotheca inuloides Cass (Asteraceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Heterotheca ineuloides Cass (Asteraceae), popularly known as árnica mexicana, is widely used in Mexican traditional medicine to treat bruises, dermatological problems, rheumatic pains, and other disorders as cancer. The major constituents in H. inuloides are cadinane type sesquiterpenes, flavonoids and phytosterols. Compounds with a cadinane skeleton have been proved to possess cytotoxic activity against human-tumor cell lines and brine shrimp, and display toxic effects in different animal species. Although this plant has been widely used, there is little available information on the safety and toxicity especially of pure compounds. AIM OF THIS STUDY: Evaluate the potential toxicity of the natural products isolated from H. inuloides and some semisynthetic derivatives. MATERIALS AND METHODS: The toxic aspects of the following natural products isolated from dried flowers of H. inuloides: 7-hydroxy-3,4-dihydrocadalene (1), 7-hydroxycadalene (2), 3,7-dihydroxy-3(4H)-isocadalen-4-one (3), (1R,4R)-1-hydroxy-4H-1,2,3,4- tetrahydrocadalen-15-oic acid (4), D-chiro-inositol (5), quercetin (6), quercetin-3,7,3'-trimethyl ether (7), quercetin-3,7,3',4'-tetramethyl ether (8), eriodictyol-7,4'-dimethyl ether (9), α-spinasterol (10), caryolan-1,9ß-diol (11) and 7-(3,3-dimethylallyloxy)-coumarin (12) as well as the toxic aspects of the semisynthetic compounds 7-acetoxy-3,4-dihydrocadalene (13), 7-benzoxy-3,4-dihydrocadalene (14), 7-acetoxycadalene (15), 7-benzoxycadalene (16), quercetin pentaacetate (17), 7-hydroxycalamenene (18), 3,8-dimethyl-5-(1-methylethyl)-1,2-naphthoquinone (19), and 4-isopropyl-1,6-dimethylbenzo[c]oxepine-7,9-dione (20). Toxic activities of compounds were determined by sulforhodamine B (SRB) assay, Artemia salina assay, RAW264.7 macrophage cells. Additionally, the acute toxicity in mouse of compound 1, the major natural sesquiterpene isolated from the acetone extract, was evaluated. RESULTS: The best cytotoxicity activity was observed for mansonone C (19) on K562 cell line with IC50 1.45 ± 0.14 µM, for 7-hydroxycadalene (2) on HCT-15 cell line with IC50 18.89 ± 1.2 µM, and for quercetin pentaacetate (17) on MCF-7 cell line with IC50 22.57 ± 2.4 µM. Sesquiterpenes mansonone C (19) and 7-hydroxy-3,4-dihydrocadalene (1) caused the strongest deleterious effects against A. salina with IC50 39.4 ± 1.07, and 45.47 ± 1.74 µM, respectively. The number of viable RAW 264.7 cells was reduced with sesquiterpenes 1 and 2 by more than 90%. In addition, the acute study of 1 revealed no lethal effects at 300 mg/kg body weight, however, a reduction in the body weight of mice, morphological changes in the tissues of the liver and kidney and toxic signs were observed at very high doses (2000 mg/kg). CONCLUSION: The results provided evidence for the cytotoxicity of Mexican arnica (H. inuloides) metabolites and may be correlated with one of the popular uses of this plant, in traditional Mexican medicine, as anticancer remedy. Among the active compounds contained in the acetone extract, the cytotoxic activity is mainly ascribable to cadinene type sesquiterpenes. In addition, evidence of acute toxicity suggests that 7-hydroxy-3,4-dihydrocadalene (1) may lead to toxicity at very high doses.

Relevance of the glutathione system in temporal lobe epilepsy: evidence in human and experimental models.

Oxidative stress, which is a state of imbalance in the production of reactive oxygen species and nitrogen, is induced by a wide variety of factors. This biochemical state is associated with diseases that are systemic as well as diseases that affect the central nervous system. Epilepsy is a chronic neurological disorder, and temporal lobe epilepsy represents an estimated 40% of all epilepsy cases. Currently, evidence from human and experimental models supports the involvement of oxidative stress during seizures and in the epileptogenesis process. Hence, the aim of this review was to provide information that facilitates the processing of this evidence and investigate the therapeutic impact of the biochemical status for this specific pathology.

Micronuclei in bone marrow and liver in relation to hepatic metabolism and antioxidant response due to coexposure to chloroform, dichloromethane, and toluene in the rat model.

Genotoxicity in cells may occur in different ways, direct interaction, production of electrophilic metabolites, and secondary genotoxicity via oxidative stress. Chloroform, dichloromethane, and toluene are primarily metabolized in liver by CYP2E1, producing reactive electrophilic metabolites, and may also produce oxidative stress via the uncoupled CYP2E1 catalytic cycle. Additionally, GSTT1 also participates in dichloromethane activation. Despite the oxidative metabolism of these compounds and the production of oxidative adducts, their genotoxicity in the bone marrow micronucleus test is unclear. The objective of this work was to analyze whether the oxidative metabolism induced by the coexposure to these compounds would account for increased micronucleus frequency. We used an approach including the analysis of phase I, phase II, and antioxidant enzymes, oxidative stress biomarkers, and micronuclei in bone marrow (MNPCE) and hepatocytes (MNHEP). Rats were administered different doses of an artificial mixture of CLF/DCM/TOL, under two regimes. After one administration MNPCE frequency increased in correlation with induced GSTT1 activity and no oxidative stress occurred. Conversely, after three-day treatments oxidative stress was observed, without genotoxicity. The effects observed indicate that MNPCE by the coexposure to these VOCs could be increased via inducing the activity of metabolism enzymes.

CYP3A4 expression in breast cancer and its association with risk factors in Mexican women.

BACKGROUND: In Mexico, breast cancer (BCa) is the leading type of cancer in women. Cytochrome P450 (CYP450) is a superfamily of major oxidative enzymes that metabolize carcinogens and many antineoplastic drugs. In addition, these enzymes have influence on tumor development and tumor response to therapy. In this report, we analyzed the protein expression in patients with BCa and in healthy women. Links with some clinic-pathological characteristic were also assessed. MATERIALS AND METHODS: Immunohistochemical analyses were conducted on 48 sets of human breast tumors and normal breast tissues enrolled in Hospital Militar de Especialidades de la Mujer y Neonatologia and Hospital Central Militar, respectively, during the time period from 2010 to 2011. Informed consent was obtained from all participants. Statistical analysis was performed using χ2 or Fisher exact tests to estimate associations and the Mann Whitney U test for comparison of group means. RESULTS: We found a significant CYP3A4 overexpression in BCa stroma and gland regions in comparison with healthy tissue. A significant association between protein expression with smoking, alcoholism and hormonal contraceptives use was also observed. Additionally, we observed estrogen receptor (ER) and progesterone receptor (PR) positive association in BCa. CONCLUSIONS: We suggest that CYP3A4 expression promotes BCa development and can be used in the prediction of tumor response to different treatments. One therapeutic approach may thus be to block CYP3A4 function.

Disminución del número de espinas dendríticas en las neuronas piramidales de la corteza motora de ratas bajo estrés prenatal / Diminution of dedritic spines in the piramidal neurons of the motor curtex in rats with prenatal stress

En el presente estudio se analizó el efecto a ratas gestantes sometidos a estrés por inmovilización. Sobre las neuronas piramidales de la capa V motora certica de la progenie, se usaron ratas hembras de la cepa Wistar que se distribuyeron al azar en dos grupos: control y experimental (n=5). Las ratas del grupo experimental fueron sometidos a estrés por inmovilización durante 2 a 6 horas diarias a lo largo de toda la gestación; las ratas grupo control se mantuvieron en condiciones normales de bioterio. Las crías de cada grupo fueron sacrificadas a los 14 y 21 días de edad. Para extraer su cerebro y obtener bloques de corteza motora que se procesaron con la técnica de Golgi Rápido. Se cuantifico el número de espinas dendríticas en segmentos de 50 micras, de una sección de 250 m de la dendrita axonal de neuronas piramidales. En el grupo experimental de 14 días, hubo reducción significativa en el número de espinas dendríticas en los segmentos de 50 a 100 y de 100 a 150 micras respecto al grupo control. Estos hallazgos sugieren que las deficiencias en la capacidad de aprendizaje, comportamiento adaptativo y de alteraciones de la actividad locomotora, reportadas en animales descendientes de madres sometidas a estrés durante la gestación pueden ser resultado de la reducción en la complejidad neuronal.