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91.
Elena Andreucci Anna Laurenzana Silvia Peppicelli Alessio Biagioni Francesca Margheri Jessica Ruzzolini Francesca Bianchini Gabriella Fibbi Mario Del Rosso Chiara Nediani Simona Serratì Livia Fucci Michele Guida Lido Calorini 《Oncology research》2020,28(9):873-884
Malignant melanoma is a highly aggressive skin cancer characterized by an elevated grade of tumor cell plasticity. Such plasticity allows adaptation of melanoma cells to different hostile conditions and guarantees tumor
survival and disease progression, including aggressive features such as drug resistance. Indeed, almost 50% of
melanoma rapidly develop resistance to the BRAFV600E inhibitor vemurafenib, with fast tumor dissemination,
a devastating consequence for patients’ outcomes. Vasculogenic mimicry (VM), the ability of cancer cells to
organize themselves in perfused vascular-like channels, might sustain tumor spread by providing vemurafenibresistant cancer cells with supplementary ways to enter into circulation and disseminate. Thus, this research
aims to determine if vemurafenib resistance goes with the acquisition of VM ability by aggressive melanoma
cells, and identify a driving molecule for both vemurafenib resistance and VM. We used two independent
experimental models of drug-resistant melanoma cells, the first one represented by a chronic adaptation of
melanoma cells to extracellular acidosis, known to drive a particularly aggressive and vemurafenib-resistant
phenotype, the second one generated with chronic vemurafenib exposure. By performing in vitro tube formation assay and evaluating the expression levels of the VM markers EphA2 and VE-cadherin by Western blotting
and flow cytometer analyses, we demonstrated that vemurafenib-resistant cells obtained by both models are
characterized by an increased ability to perform VM. Moreover, by exploiting the CRISPR-Cas9 technique and
using the urokinase plasminogen activator receptor (uPAR) inhibitor M25, we identified uPAR as a driver of
VM expressed by vemurafenib-resistant melanoma cells. Thus, uPAR targeting may be successfully leveraged
as a new complementary therapy to inhibit VM in drug-resistant melanoma patients, to counteract the rapid
progression and dissemination of the disease. 相似文献
92.
《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy. 相似文献
93.
《Joint, bone, spine : revue du rhumatisme》2020,87(1):103-104
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97.
目的:研究藏药如意珍宝丸对硝酸甘油致偏头痛模型大鼠下行痛觉调制通道中心区域中脑导水管内神经生长因子(Nerve Growth Factor,NGF)、酪氨酸激酶A(Tyrosine Kinase A,TrkA)、瞬时感受器电位香草酸受体1(Transient Receptor Potential Vanilloid Receptor 1,TRPV1)的表达影响,探究该药干预神经源炎性痛敏性偏头痛的作用机制。方法:以颈部皮下注射硝酸甘油方法复制大鼠偏头痛模型,以如意珍宝丸为药物实验组,琥珀酸舒马普坦为阳性对照组,采用ELISA和Real-Time PCR法检测外周血清及中脑组织NGF、TrkA、TRPV1蛋白及基因表达水平,观察藏药如意珍宝丸对硝酸甘油致偏头痛模型大鼠下行痛觉调制系统的影响。结果:与空白组比较,模型组血清NGF、TrkA、TRPV1蛋白表达显著上升(P0.05);中脑NGF、TrkA、TRPV1基因表达差异性升高(P0.05)。与模型组比较,如意珍宝丸预防组可降低NGF、TRPV1蛋白表达(P0.05);如意珍宝丸观察组能使NGF、TrkA蛋白表达和NGF、TrkA、TRPV1 mRNA表达均降低(P0.05或P0.01)。结论:NGF、TrkA共同参与了下行疼痛调控中TRPV1介导的偏头痛发生;藏药如意珍宝丸可降低NGF、TrkA对TRPV1的上调作用,起到抑制神经源炎性痛敏性偏头痛的作用。 相似文献
98.
Dinja T. Kruger Xanthippi Alexi Mark Opdam Karianne Schuurman Leonie Voorwerk Joyce Sanders Vincent van der Noort Epie Boven Wilbert Zwart Sabine C. Linn 《International journal of cancer. Journal international du cancer》2020,146(8):2348-2359
Preclinical studies indicate that activated IGF-1R can drive endocrine resistance in ER-positive (ER+) breast cancer, but its clinical relevance is unknown. We studied the effect of IGF-1R signaling on tamoxifen benefit in patients and we searched for approaches to overcome IGF-1R-mediated tamoxifen failure in cell lines. Primary tumor blocks from postmenopausal ER+ breast cancer patients randomized between adjuvant tamoxifen versus nil were recollected. Immunohistochemistry for IGF-1R, p-IGF-1R/InsR, p-ERα(Ser118), p-ERα(Ser167) and PI3K/MAPK pathway proteins was performed. Multivariate Cox models were employed to assess tamoxifen efficacy. The association between p-IGF-1R/InsR and PI3K/MAPK pathway activation in MCF-7 and T47D cells was analyzed with Western blots. Cell proliferation experiments were performed under various growth-stimulating and -inhibiting conditions. Patients with ER+, IGF-1R-positive breast cancer without p-IGF-1R/InsR staining (n = 242) had tamoxifen benefit (HR 0.41, p = 0.0038), while the results for p-IGF-1R/InsR-positive patients (n = 125) were not significant (HR 0.95, p = 0.3). High p-ERα(Ser118) or p-ERα(Ser167) expression was associated with less tamoxifen benefit. In MCF-7 cells, IGF-1R stimulation increased phosphorylation of PI3K/MAPK proteins and ERα(Ser167) regardless of IGF-1R overexpression. This could be abrogated by the dual IGF-1R/InsR inhibitor linsitinib, but not by the IGF-IR-selective antibody 1H7. In MCF-7 and T47D cells, stimulation of the IGF-1R/InsR pathway resulted in cell proliferation regardless of tamoxifen. Abrogation of cell growth was regained by addition of linsitinib. In conclusion, p-IGF-1R/InsR positivity in ER+ breast cancer is associated with reduced benefit from adjuvant tamoxifen in postmenopausal patients. In cell lines, stimulation rather than overexpression of IGF-1R is driving tamoxifen resistance to be abrogated by linsitinib. 相似文献
99.
《Clinical breast cancer》2020,20(5):e589-e599
PurposeTo investigate the prognosis of single hormone receptor–positive (HR+) breast cancer (estrogen receptor [ER] positive and progesterone receptor [PR] negative, and ER−PR+) compared to double HR+ (ER+PR+) and double HR− (ER−PR−) tumors.MethodsWe included 531,605 cases of invasive breast cancer between 1990 and 2012 from the US Surveillance, Epidemiology, and End Results (SEER) database for study and classified cases into 4 phenotypes according to expression of ER and PR: ER+PR+, ER+PR−, ER−PR+, and ER−PR−.ResultsOverall, 66,091 ER+PR− tumors and 9320 ER−PR+ tumors were identified. The clinical characteristics of the ER+PR− group were similar to those of the double HR+ group, while those of the ER−PR+ and double HR− groups were similar. Overall survival of patients with single HR+ tumors was intermediate between that of double HR+ and double HR− tumors. However, we observed no differences in disease-specific survival between ER−PR+ and ER−PR− patients. In multivariate analysis, outcomes were similar. Relative to the double HR+ patient group, risk of death in the ER+PR− group was higher (hazard ratio, 1.422, 95% confidence interval, 1.394-1.452). However, risk of death was comparable between ER−PR+ and ER−PR− patients (hazard ratio, 1.03; 95% confidence interval, 0.98-1.08). Multivariate Cox proportional analysis showed that survival times of patients in the younger age bracket (< 60 years), those positive for human epidermal growth factor receptor 2 (HER2), and patients with tumor stage I-III were longer in the ER−PR+ group.ConclusionDisease-specific survival of single HR+ tumor cases was longer than that of double HR− tumors but poorer than double HR+ tumors. However, differences in disease-specific survival were not significant between the ER−PR+ and ER−PR− groups. 相似文献
100.
ABSTRACT Tryptophan (Trp) is not only a nutrient enhancer but also has systemic effects. Trp metabolites signaling through the well-known aryl hydrocarbon receptor (AhR) constitute the interface of microbiome-gut-brain axis. However, the pathway through which Trp metabolites affect central nervous system (CNS) function have not been fully elucidated. AhR participates in a broad variety of physiological and pathological processes that also highly relevant to intestinal homeostasis and CNS diseases. Via the AhR-dependent mechanism, Trp metabolites connect bidirectional signaling between the gut microbiome and the brain, mediated via immune, metabolic, and neural (vagal) signaling mechanisms, with downstream effects on behavior and CNS function. These findings shed light on the complex Trp regulation of microbiome-gut-brain axis and add another facet to our understanding that dietary Trp is expected to be a promising noninvasive approach for alleviating systemic diseases. 相似文献