Successful post-incomplete resection management of gastrointestinal stromal tumor using imatinib based on adenosine triphosphate-based tumor sensitivity assay in a dog.

Gastrointestinal stromal tumors arising from gastric cardia are uncommon in dogs. A few studies have shown the effectiveness of tyrosine kinase inhibitors in the treatment of canine gastrointestinal stromal tumors, but no standardized protocols are currently available. An 11-year-old spayed female Maltese dog was diagnosed with a gastrointestinal stromal tumor using histopathological and immunohistochemical analyses. An adenosine triphosphate-based tumor chemosensitivity assay revealed that imatinib at lower concentrations had a stronger inhibitory effect than toceranib. Based on the results of the assay, the dog was treated with imatinib after surgery. After 28 mo of therapy, there was no recurrence of the tumor. Key clinical message: Adenosine triphosphate-based tumor chemosensitivity assays may help clinicians to select appropriate postoperative chemotherapeutic drugs for incompletely resected gastrointestinal stromal tumors in dogs.

Gestion réussie à la suite d'une résection incomplète d'une tumeur stromale gastro-intestinale à l'aide de l'imatinib basée sur un test de sensibilité tumorale à base d'adénosine triphosphate chez un chien. Les tumeurs stromales gastro-intestinales résultant du cardia gastrique sont rares chez le chien. Quelques études ont montré l'efficacité des inhibiteurs de la tyrosine kinase dans le traitement des tumeurs stromales gastrointestinales canines, mais aucun protocole standardisé n'est actuellement disponible. Une chienne maltaise stérilisée de 11 ans a reçu un diagnostic de tumeur stromale gastro-intestinale à l'aide d'analyses histopathologiques et immunohistochimiques. Un test de chimiosensibilité tumorale à base d'adénosine triphosphate a révélé que l'imatinib à des concentrations plus faibles avait un effet inhibiteur plus fort que le tocéranib. Sur la base des résultats du test, le chien a été traité avec de l'imatinib après l'opération. Après 28 mois de traitement, il n'y a eu aucune récidive de la tumeur.Message clinique clé :Les tests de chimiosensibilité tumorale à base d'adénosine triphosphate peuvent aider les cliniciens à sélectionner les médicaments chimiothérapeutiques postopératoires appropriés pour les tumeurs stromales gastro-intestinales incomplètement réséquées chez le chien.(Traduit par Dr Serge Messier).

Upregulation of p300 in paclitaxel-resistant TNBC: implications for cell proliferation via the PCK1/AMPK axis.

OBJECTIVE: To explore the role of p300 in the context of paclitaxel (PTX) resistance in triple-negative breast cancer (TNBC) cells, focusing on its interaction with the phosphoenolpyruvate carboxykinase 1 (PCK1)/adenosine monophosphate-activated protein kinase (AMPK) pathway. METHODS: The expression of p300 and PCK1 at the messenger ribonucleic acid (mRNA) level was detected using a quantitative polymerase chain reaction. The GeneCards and GEPIA databases were used to investigate the relationship between p300 and PCK1. The MDA-MB-231/PTX cell line, known for its PTX resistance, was chosen to understand the specific role of p300 in such cells. The Lipofectamine™ 3000 reagent was used to transfer the p300 small interfering RNA and the overexpression of PCK1 plasmid into MDA-MB-231/PTX. The expression levels of p300, PCK1, 5'AMPK and phosphorylated AMPK (p-AMPK) were determined using the western blot test. RESULTS: In TNBC cancer tissue, the expression of p300 was increased compared with TNBC paracancerous tissue (P < 0.05). In the MDA-MB-231 cell line of TNBC, the expression of p300 was lower than in the PTX-resistant TNBC cells (MDA-MB-231/PTX) (P < 0.05). The PCK1 expression was decreased in the TNBC cancer tissue compared with TNBC paracancerous tissue, and the PCK1 expression was reduced in MDA-MB-231/PTX than in MDA-MB-231 (P < 0.05) indicating that PCK1 was involved in the resistance function. Additionally, p-AMPK was decreased in MDA-MB-231/PTX compared with MDA-MB-231 (P < 0.05). The adenosine triphosphate (ATP) level was also detected and was significantly lower in MDA-MB-231/PTX than in MDA-MB-231 (P < 0.05). Additionally, cell proliferation increased significantly in MDA-MB-231/PTX at 48 and 72 h (P < 0.05) suggesting that MDA-MB-231/PTX cells obtained the resistance function which was associated with AMPK and ATP level. When p300 was inhibited, p-AMPK and ATP levels elevated in MDA-MB-231/PTX (P < 0.05). When PCK1 was suppressed, the ATP consumption rate decreased, and cell proliferation increased (P < 0.05). However, there were no changes in p300. CONCLUSIONS: In MDA-MB-231/PTX, p300 can inhibit p-AMPK and ATP levels by inhibiting PCK1 expression. Our findings suggest that targeting p300 could modulate the PCK1/AMPK axis, offering a potential therapeutic avenue for overcoming PTX resistance in TNBC.

Mass Spectrometry Investigation of Some ATP-Binding Cassette (ABC) Proteins.

Drug resistance remains one of the main causes of poor outcome in cancer therapy. It is also becoming evident that drug resistance to both chemotherapy and to antibiotics is driven by more than one mechanism. So far, there are at least eight recognized mechanisms behind such resistance. In this review, we choose to discuss one of these mechanisms, which is known to be partially driven by a class of transmembrane proteins known as ATP-binding cassette (ABC) transporters. In normal tissues, ABC transporters protect the cells from the toxic effects of xenobiotics, whereas in tumor cells, they reduce the intracellular concentrations of anticancer drugs, which ultimately leads to the emergence of multidrug resistance (MDR). A deeper understanding of the structures and the biology of these proteins is central to current efforts to circumvent resistance to both chemotherapy, targeted therapy, and antibiotics. Understanding the biology and the function of these proteins requires detailed structural and conformational information for this class of membrane proteins. For many years, such structural information has been mainly provided by X-ray crystallography and cryo-electron microscopy. More recently, mass spectrometry-based methods assumed an important role in the area of structural and conformational characterization of this class of proteins. The contribution of this technique to structural biology has been enhanced by its combination with liquid chromatography and ion mobility, as well as more refined labelling protocols and the use of more efficient fragmentation methods, which allow the detection and localization of labile post-translational modifications. In this review, we discuss the contribution of mass spectrometry to efforts to characterize some members of the ATP-binding cassette (ABC) proteins and why such a contribution is relevant to efforts to clarify the link between the overexpression of these proteins and the most widespread mechanism of chemoresistance.

Effect of the mitochondrial uncoupling agent BAM15 against the Toxoplasma gondii RH strain and Prugniaud strain.

BACKGROUND: Toxoplasmosis is a zoonotic disease caused by the infection of the protozoa Toxoplasma gondii (T. gondii), and safe and effective therapeutic drugs are lacking. Mitochondria, is an important organelle that maintains T. gondii survival, however, drugs targeting mitochondria are lacking. METHODS: The cytotoxicity of BAM15 was detected by CCK-8 and the in vitro effects of BAM15 was detected by qPCR, plaque assay and flow cytometry. Furthermore, the ultrastructural changes of T. gondii after BAM15 treatment were observed by transmission electron microscopy, and further the mitochondrial membrane potential (ΔΨm), ATP level and reactive oxygen species (ROS) of T. gondii after BAM15 treatment were detected. The pharmacokinetic experiments and in vivo infection assays were performed in mice to determine the in vivo effect of BAM15. RESULTS: BAM15 had excellent anti-T. gondii activity in vitro and in vivo with an EC50 value of 1.25 µM, while the IC50 of BAM15 in Vero cells was 27.07 µM. Notably, BAM15 significantly inhibited proliferation activity of T. gondii RH strain and Prugniaud strain (PRU), caused T. gondii death. Furthermore, BAM15 treatment induced T. gondii mitochondrial vacuolation and autolysis by TEM. Moreover, the decrease in ΔΨm and ATP level, as well as the increase in ROS production further confirmed the changes CONCLUSIONS: Our study identifies a useful T. gondii mitochondrial inhibitor, which may also serve as a leading molecule to develop therapeutic mitochondrial inhibitors in toxoplasmosis.'

Utilizing non-coding RNA-mediated regulation of ATP binding cassette (ABC) transporters to overcome multidrug resistance to cancer chemotherapy.

Multidrug resistance (MDR) is one of the primary factors that produces treatment failure in patients receiving cancer chemotherapy. MDR is a complex multifactorial phenomenon, characterized by a decrease or abrogation of the efficacy of a wide spectrum of anticancer drugs that are structurally and mechanistically distinct. The overexpression of the ATP-binding cassette (ABC) transporters, notably ABCG2 and ABCB1, are one of the primary mediators of MDR in cancer cells, which promotes the efflux of certain chemotherapeutic drugs from cancer cells, thereby decreasing or abolishing their therapeutic efficacy. A number of studies have suggested that non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), play a pivotal role in mediating the upregulation of ABC transporters in certain MDR cancer cells. This review will provide updated information about the induction of ABC transporters due to the aberrant regulation of ncRNAs in cancer cells. We will also discuss the measurement and biological profile of circulating ncRNAs in various body fluids as potential biomarkers for predicting the response of cancer patients to chemotherapy. Sequence variations, such as alternative polyadenylation of mRNA and single nucleotide polymorphism (SNPs) at miRNA target sites, which may indicate the interaction of miRNA-mediated gene regulation with genetic variations to modulate the MDR phenotype, will be reviewed. Finally, we will highlight novel strategies that could be used to modulate ncRNAs and circumvent ABC transporter-mediated MDR.

An integrated strategy to evaluate active substances of Astragali Radix-Carthami Flos combination on the treatment of cerebral ischemia reperfusion injury based on TQSM polypharmacokinetics and pharmacodynamics.

As a classic herb pair, Astragali Radix-Carthami Flos (AR-CF) has revealed good biological activity in the treatment of cerebral ischemia/reperfusion injury (CI/RI), which remained to be further clarified together with the underlying efficacy related compounds for material basis. In this study, the nine formulations were obtained by L9 (34) orthogonal array design of four active fractions (saponin and flavonoid extracted from AR, safflower yellow and safflower red extracted from CF). The concentrations of eleven components and the levels of four biochemical indicators in rat plasma were continuously detected after intragastric administration of nine formulations, respectively. The collected data were analyzed by sigmoid-Emax function to understand the polypharmacokinetics and pharmacodynamics (PK-PD) behaviors of multi-components. Using the total quantum statistic moment polypharmacokinetics and its similarity method, the importance of four active fractions from AR-CF in relieving CI/RI was discussed and the Q-markers were screened. The results represented that a reliable and robust liquid chromatography tandem mass spectrometry method been successfully established to simultaneously determine the concentrations of eleven components in rat plasma. The AUC and MRT values of components from flavonoid fraction had the greatest contribution to AUCT and MRTT values. The transitivity in vivo of calycosin-7-O-ß-Dglucoside (CG), astragaloside IV (AIV) and hydroxysafflor yellow A (HYA) was closer to polypharmacokinetics behavior. All formulations up/down-regulated the levels of GSH-Px and ATP/ET and LDH to varying degrees, among which formulation 7 had the best regulating effect. By drawing the time-concentration-effect curve, clockwise hysteresis loops were presented in the time-concentration-effect relationships between eleven components and LDH/ET, while the relationship between eleven components and ATP/GSH-Px expressed as anticlockwise hysteresis loops. In conclusion, the combination based on the combination principle of formulation 7 produced the best alleviation effect on CI/RI, and flavonoid fraction might played key role in this process. The CG, AIV and HYA were identified as Q-markers. This research offered a novel strategy for exploring the active substances, and provided further understanding regarding the development of drugs for the treatment of cerebral ischemia-reperfusion injury.

Effectivity of Bromocriptine Administration Towards Prolactin Positive Breast Cancer Receiving Anthracycline-Based Chemotherapy: A Literature Review.

Breast cancer is among the deadliest gynecology cancers in the world. However, the management of advanced-stage breast cancer is often harder as a result of chemoresistance. This review aimed to discover the effect of bromocriptine on prolactin-positive breast cancer patients who received anthracycline-based chemotherapy. It is known that anthracycline works by inhibiting topoisomerase IIα (TOP2A), forming free radicals, binding DNA, and altering cell homeostasis, hence stopping the cell cycle and inducing cell death. However, reduction of TOP2A expression and increased glutathione s-transferase (GST) and ATP-binding cassette (ATP) membrane activity increase anthracycline efflux from the cell membrane, hence reducing its effectivity. Prolactin is one of the most common chemoresistance agents whose complex with its receptor will induce JAK/STAT pathway to increase GST. The regulation of Bcl-2 and ERK was also determined by prolactin. Bromocriptine is an agonist of the D2 dopamine receptor that inhibits adenyl cyclase and a D1 dopamine weak antagonist. Bromocriptine could reduce prolactin serum and receptors in various cases. Some studies have found that bromocriptine could improve the effectiveness of chemotherapy regimens, including cancer-related hyperprolactinemia, breast cancer that underwent cisplatin, and taxanes. Therefore, bromocriptine offers potential as it could improve outcomes and reduce resistance in prolactin-positive breast cancer patients who are administered anthracycline-based neoadjuvant chemotherapy.

In vivo effects of adenosine 5´-triphosphate on rat preneoplastic liver / Efecto in vivo de adenosina 5´-trifosfato sobre el hígado preneoplásico de la rata

The utilization of adenosine 5´-triphosphate (ATP ) infusions to inhibit the growth of some human and animals tumors was based on the anticancer activity observed in in vitro and in vivo experiments, but contradictory results make the use of ATP in clinical practice rather controversial. Moreover, there is no literature regarding the use of ATP infusions to treat hepatocarcinomas. The purpose of this study was to investigate whether ATP prevents in vivo oncogenesis in very-early-stage cancer cells in a well characterized two-stage model of hepatocarcinogenesis in the rat. As we could not preclude the possible effect due to the intrinsic properties of adenosine, a known tumorigenic product of ATP hydrolysis, the effect of the administration of adenosine was also studied. Animals were divided in groups: rats submitted to the two stage preneoplasia initiation/promotion model of hepatocarcinogenesis, rats treated with intraperitoneal ATP or adenosine during the two phases of the model and appropriate control groups. The number and volume of preneoplastic foci per liver identified by the expression of glutathione S-transferase placental type and the number of proliferating nuclear antigen positive cells significantly increased in ATP and adenosine treated groups. Taken together, these results indicate that in this preneoplastic liver model, ATP as well as adenosine disturb the balance between apoptosis and proliferation contributing to malignant transformation.

La utilización de adenosina 5´-trifosfato (ATP ) para inhibir el crecimiento de algunos tumores en humanos y en animales se basa en la actividad anticancerígena observada en experimentos in vitro e in vivo. El uso del ATP en la práctica clínica es discutido debido a resultados contradictorios. Por otra parte, no existen antecedentes del uso de ATP en el tratamiento de hepatocarcinomas. El objetivo del presente estudio fue determinar si el ATP previene la oncogénesis in vivo en un modelo de preneoplasia hepática murina de dos etapas. Para determinar la probable contribución de la adenosina, producto de la hidrólisis de ATP y descrita como tumorigénica, se estudió también el efecto del nucleósido exógeno sobre los focos preneoplásicos. Los animales se dividieron en grupos: ratas sometidas al modelo de preneoplasia de iniciación/promoción, ratas tratadas con ATP o adenosina intraperitonealmente durante las dos fases del modelo y los correspondientes grupos controles. El número y el volumen de focos preneoplásicos por hígado, identificados por la expresión de la forma placentaria de la glutation S- transferasa de rata y el número de células positivas para el antígeno nuclear proliferante, aumentaron significativamente en los grupos tratados con ATP y adenosina. Los resultados en su conjunto indican que en este modelo preneoplásico, el ATP y la adenosina alteran el balance entre apoptosis y proliferación, contribuyendo a la transformación maligna.

Comportamento da polpa dental após pulpotomia e aplicaçäo de trifosfato de adenosina, hidróxido de cálcio e combinaçäo de ambos: estudo histológico em dentes humanos / Behaviour of dental pulps after pulpotomy and application of adenosin three-phosphate, calcium hydroxide and both combination: histological study in human teeth

A finalidade desta pesquisa foi verificar o comportamento da polpa dentária após pulpotomia e proteçäo do remanescente pulporradicular com os seguintes materiais: trifosfato de adenosina e hidróxido de cálcio com e sem tratamento prévio com trifosfato de adenosina. Foram utilizados 80 dentes pré-molares de pacientes com idade de 10 a 16 anos. Decorridos períodos de observaçäo de 7 e 40 dias, os dentes foram extraídos e submetidos à análise radiográfica e histológica. Com base nos resultados obtidos as condiçöes experimentais em que foi realizado este trabalho, pôde-se concluir que: Em relaçäo à análise histopatológica: - o ATP puro se mostrou como um material irritante ao tecido pulpar; - o hidróxido de cálcio associado ou näo às soluçöes de ATP foram bem tolerados pelo tecido pulpar; - o processo de reparo pulpar foi acelerado quando utilizada a soluçäo de ATP näo-tamponada, previamente ao hidróxido de cálcio...