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BACKGROUND: Leaf explants are major materials in plant tissue cultures. Incubation of detached leaves on phytohormone-containing media, which is an important process for producing calli and regenerating plants, change their cell fate. Although hormone signaling pathways related to cell fate transition have been widely studied, other molecular and physiological events occurring in leaf explants during this process remain largely unexplored. RESULTS: Here, we identified that ethylene signals modulate expression of pathogen resistance genes and anthocyanin accumulation in leaf explants, affecting their survival during culture. Anthocyanins accumulated in leaf explants, but were not observed near the wound site. Ethylene signaling mutant analysis revealed that ethylene signals are active and block anthocyanin accumulation in the wound site. Moreover, expression of defense-related genes increased, particularly near the wound site, implying that ethylene induces defense responses possibly by blocking pathogenesis via wounding. We also found that anthocyanin accumulation in non-wounded regions is required for drought resistance in leaf explants. CONCLUSIONS: Our study revealed the key roles of ethylene in the regulation of defense gene expression and anthocyanin biosynthesis in leaf explants. Our results suggest a survival strategy of detached leaves, which can be applied to improve the longevity of explants during tissue culture.
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Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Antocianinas/metabolismo , Etilenos/metabolismo , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Extracts of Prunella vulgaris have been shown to exert antiestrogenic effects. To identify the compounds responsible for these actions, we isolated the constituents of P. vulgaris and tested their individual antiestrogenic effects. Rosmarinic acid, caffeic acid, ursolic acid (UA), oleanolic acid, hyperoside, rutin and betulinic acid (BA) were isolated from the flower stalks of P. vulgaris var. lilacina Nakai (Labiatae). Among these constituents, UA and BA showed significant antiestrogenic effects, measured as a decrease in the mRNA level of GREB1, an estrogen-responsive protein; the effects of BA were stronger than those of UA. UA and BA were capable of suppressing estrogen response element (ERE)-dependent luciferase activity and expression of estrogen-responsive genes in response to exposure to estradiol, further supporting the suppressive role of these compounds in estrogen-induced signaling. However, neither UA nor BA was capable of suppressing estrogen signaling in cells ectopically overexpressing estrogen receptor α (ERα). Furthermore, both mRNA and protein levels of ERα were reduced by treatment with UA or BA, suggesting that UA and BA inhibit estrogen signaling by suppressing the expression of ERα. Interestingly, both compounds enhanced prostate-specific antigen promoter activity. Collectively, these findings demonstrate that UA and BA are responsible for the antiestrogenic effects of P. vulgaris and suggest their potential use as therapeutic agents against estrogen-dependent tumors.
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Moduladores de Receptor Estrogênico/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Triterpenos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Moduladores de Receptor Estrogênico/isolamento & purificação , Receptor alfa de Estrogênio/genética , Feminino , Humanos , Células MCF-7 , Masculino , Proteínas de Neoplasias/genética , Triterpenos Pentacíclicos , Fitoterapia , Plantas Medicinais/química , Regiões Promotoras Genéticas , Antígeno Prostático Específico/genética , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Prunella/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triterpenos/isolamento & purificação , Ácido Betulínico , Ácido UrsólicoRESUMO
Serine is a key contributor to the generation of one-carbon units for DNA synthesis during cellular proliferation. In addition, it plays a crucial role in the production of antioxidants that prevent abnormal proliferation and stress in cancer cells. In recent studies, the relationship between cancer metabolism and the serine biosynthesis pathway has been highlighted. In this context, 3-phosphoglycerate dehydrogenase (PHGDH) is notable as a key enzyme that functions as the primary rate-limiting enzyme in the serine biosynthesis pathway, facilitating the conversion of 3-phosphoglycerate to 3-phosphohydroxypyruvate. Elevated PHGDH activity in diverse cancer cells is mediated through genetic amplification, posttranslational modification, increased transcription, and allosteric regulation. Ultimately, these characteristics allow PHGDH to not only influence the growth and progression of cancer but also play an important role in metastasis and drug resistance. Consequently, PHGDH has emerged as a crucial focal point in cancer research. In this review, the structural aspects of PHGDH and its involvement in one-carbon metabolism are investigated, and PHGDH is proposed as a potential therapeutic target in diverse cancers. By elucidating how PHGDH expression promotes cancer growth, the goal of this review is to provide insight into innovative treatment strategies. This paper aims to reveal how PHGDH inhibitors can overcome resistance mechanisms, contributing to the development of effective cancer treatments.
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Neoplasias , Fosfoglicerato Desidrogenase , Fosfoglicerato Desidrogenase/metabolismo , Fosfoglicerato Desidrogenase/antagonistas & inibidores , Fosfoglicerato Desidrogenase/genética , Humanos , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Terapia de Alvo Molecular , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Serina/metabolismoRESUMO
Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with inferior outcomes owing to its low treatment response and high invasiveness. Based on abundant cancer-associated fibroblasts (CAFs) and frequent mutation of breast cancer-associated 1 (BRCA1) in TNBC, the characteristics of CAFs in TNBC patients with BRCA1 mutation compared to wild-type were investigated using single-cell analysis. Intriguingly, we observed that characteristics of inflammatory CAFs (iCAFs) were enriched in patients with BRCA1 mutation compared to the wild-type. iCAFs in patients with BRCA1 mutation exhibited outgoing signals to endothelial cells (ECs) clusters, including chemokine (C-X-C motif) ligand (CXCL) and vascular endothelial growth factor (VEGF). During CXCL signaling, the atypical chemokine receptor 1 (ACKR1) mainly interacts with CXCL family members in tumor endothelial cells (TECs). ACKR1-high TECs also showed high expression levels of angiogenesis-related genes, such as ANGPT2, MMP1, and SELE, which might lead to EC migration. Furthermore, iCAFs showed VEGF signals for FLT1 and KDR in TECs, which showed high co-expression with tip cell marker genes, including ZEB1 and MAFF, involved in sprouting angiogenesis. Moreover, BRCA1 mutation patients with relatively abundant iCAFs and tip cell gene expression exhibited a limited response to neoadjuvant chemotherapy, including cisplatin and bevacizumab. Importantly, our study observed the intricate link between iCAFs-mediated angiogenesis and chemoresistance in TNBC with BRCA1 mutation.
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Obesity, now officially recognized as a disease requiring intervention, has emerged as a significant health concern due to its strong association with elevated susceptibility to diverse diseases and various types of cancer, including breast cancer. The link between obesity and cancer is intricate, with obesity exerting a significant impact on cancer recurrence and elevated mortality rates. Among the various subtypes of breast cancer, triple-negative breast cancer (TNBC) is the most aggressive, accounting for 15% to 20% of all cases. TNBC is characterized by low expression of estrogen receptors and progesterone receptors as well as the human epidermal growth factor 2 receptor protein. This subtype poses distinct challenges in terms of treatment response and exhibits strong invasiveness. Furthermore, TNBC has garnered attention because of its association with obesity, in which excess body fat and reduced physical activity have been identified as contributing factors to the increased incidence of this aggressive form of breast cancer. In this comprehensive review, the impact of obesity on TNBC was explored. Specifically, we focused on the three key mechanisms by which obesity affects TNBC development and progression: modification of the immune profile, facilitation of fibrosis, and initiation of senescence. By comprehensively examining these mechanisms, we illuminated the complex interplay between TNBC and obesity, facilitating the development of novel approaches for prevention, early detection, and effective management of this challenging disease.
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Polo like kinase 4 (Plk4) is a tightly regulated serine threonine kinase that governs centriole duplication. Increased Plk4 expression, which is a feature of many common human cancers, causes centriole overduplication, mitotic irregularities, and chromosomal instability. Plk4 can also promote cancer invasion and metastasis through regulation of the actin cytoskeleton. Herein we demonstrate physical interaction of Plk4 with FAM46C/TENT5C, a conserved protein of unknown function until recently. FAM46C localizes to centrioles, inhibits Plk4 kinase activity, and suppresses Plk4-induced centriole duplication. Interference with Plk4 function by FAM46C was independent of the latter's nucleotidyl transferase activity. In addition, FAM46C restrained cancer cell invasion and suppressed MDA MB-435 cancer growth in a xenograft model, opposing the effect of Plk4. We demonstrate loss of FAM46C in patient-derived colorectal cancer tumor tissue that becomes more profound with advanced clinical stage. These results implicate FAM46C as a tumor suppressor that acts by inhibiting Plk4 activity.
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Genes Supressores de Tumor , Nucleotidiltransferases/metabolismo , Animais , Linhagem Celular Tumoral , Centríolos/metabolismo , Neoplasias Colorretais/patologia , Sequência Conservada , Humanos , Camundongos Nus , Fosforilação , Ligação Proteica , Domínios Proteicos , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
[This corrects the article on p. 115 in vol. 21, PMID: 26356607.].
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OBJECTIVE: The purpose of this study was to investigate the aortic isthmus (AoI) flow difference between larger fetus and smaller fetus of twin; and to evaluate the predictive value of early diagnosis of hemodynamic change in twin growth. METHODS: This prospective study on 49 pairs of twin fetuses was performed to obtain AoI blood flow data. Cases with structural or chromosomal abnormalities and co-twin death were excluded. The interval from examination to delivery was within 4 weeks and 3 cases over 4 weeks interval were re-examined. Assessment of fetal AoI Doppler parameters were peak systolic velocity (PSV), end-diastolic velocity, times-averaged maximum velocities, pulsatility index (PI), and resistance index (RI). According to the direction of the diastolic flow in the AoI, antegrade and retrograde flow were made and was used to analyze the perinatal outcomes of each fetus. The predictive value of AoI Doppler parameters in predicting fetal growth was obtained by using ANOVA and logistic regression analysis of quantitative variables in each fetus of twins. RESULTS: There were significant differences in the gestational weeks at delivery, birth weight and the incidence of growth discordance over 20% or more between monochorionic twin and dichorionic twin. The AoI PI and RI were significantly higher in smaller fetus than in larger regardless of chorionicity. Retrograde flow was noted in 8 of 98 cases (8.2%) and the only one case was of the larger fetus and the others were smaller fetuses of twin. Significant correlations were found between the AoI PI and birthweight (P=0.018) and between the PSV and growth discordance (P=0.032). In monochorionic twin, linear correlation was shown between the AoI PI and birthweight (P=0.004) and between AoI PI and growth discordance (P=0.031). Also, the meaningful correlation between the PSV and birthweight (P=0.036) was found by using logistic regression analyses. CONCLUSION: On the basis of our observation, AoI PI has revealed their hemodynamic status and this result may improve the understanding of growth patterns in twins.
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Sclerosing stromal tumor (SST) was first delineated as a distinct ovarian sex cord stromal tumor in 1973 by Chalvardjian and Scully. It is a benign neoplasm, distinguished from other ovarian stromal tumors by the production of collagen and a pseudolobular pattern, and it tends to occur in the second and third decades of life in diagnosed patients. We discovered two rare cases of SST in post-menopausal women which are the topic of this report. These case studies are accompanied by a brief review of the literature.
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OBJECTIVE: To investigate clinical factors affecting the timing of delivery in twin pregnancies in order to minimize perinatal complications. METHODS: A retrospective study involved 163 twin pregnancies delivered from January 2006 to September 2011 at Gachon University Gil Medical Center. These cases were divided into three groups based on the delivery timing: less than 32 weeks' gestation (group A), between 32 and 35+6 weeks' gestation (group B), and over 36 weeks' gestation (group C). Clinical factors including maternal age, parity, presence of premature uterine contraction, presence of premature rupture of membrane, white blood cell, high sensitive C-reactive protein level, cervical dilatation, maternal complication, chorionicity, twin specific complication, and perinatal complication were analyzed for each group. RESULTS: In group B, the timing of delivery was postponed for 14 days or more from the time of admission, and there were fewer numbers of babies with low Apgar score at birth compared with other groups. The frequency of uterine contraction (P<0.001), presence of premature rupture of membranes (P=0.017), dilatation of cervix (P<0.001), increased white blood cell and high sensitive C-reactive protein levels (P=0.002, P<0.001) were important clinical factors during decision making process of delivery timing in twin pregnancies. Twin specific fetal conditions, such as twin-twin transfusion syndrome and discordant growth (over 25% or more) were shown more frequently in group A. However, there were no significant statistical differences among three groups (P=0.06, P=0.14). CONCLUSION: Proper management for preventing premature contraction and inflammation can be essential in twin pregnancies until 32 weeks' gestation, and may decrease maternal and perinatal complications.
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OBJECTIVE: To evaluate correlation of preoperative anemia with clinical outcomes in patients with early stage cervical cancer who were treated with radical hysterectomy and lymph node dissection. METHODS: Patients who underwent radical hysterectomy and lymph node dissection for cervical cancer from January 2001 to February 2012 were included in this study. Clinicopatholgoical factors included in univariate and multivariate analysis were age, tumor histology, FIGO (International Federation of Gyneocology and Obstetrics) stage, preoperative hemoglobin, depth of invasion, tumor size, parametrial involvement, resection margin, and lymph node status. RESULTS: A total of 387 patients were retrospectively analyzed in this study; 141 patients (36.4%) had preoperative anemia (hemoglobin <12 g/dL) and 16 out of 141 patients (11.3%) received blood transfusion for correction of preoperative anemia. Patients with preoperative anemia showed significant association with age <50 years, more advanced stage, non-squamous cell carcinoma histology, larger tumor size, deeper stromal invasion, and lymph node metastasis (P<0.05). Both relapse-free survival and overall survival were worse in patients with preoperative anemia in univariate analysis. In multivariate analysis, overall survival was worse in patients with preoperative anemia, but relapse-free survival was not associated with preoperative anemia. In the intergroup analysis of anemic patients for the effect of preoperative blood transfusion, preoperative anemia correction did not affect survival. CONCLUSION: Preoperative anemia was not an independent prognostic factor for survival in patients with early cervical cancer. However, it was associated with poor prognostic factors. Further study in large population is needed.