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1.
Front Pharmacol ; 14: 1234262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074113

RESUMO

Backgrounds: Brain metastases occur in approximately 30% of patients with non-small-cell lung cancer (NSCLC). Therefore, the free drug concentration in cerebrospinal fluid (CSF) is strongly associated with the clinical efficacy. Purpose: The present study aimed to develop physiologically based pharmacokinetic (PBPK) models that can predict the steady-state trough concentration (Ctrough) in plasma and CSF, as well as anaplastic lymphoma kinase (ALK) occupancy (AO), for three inhibitors: crizotinib (CRI), alectinib (ALE), and lorlatinib (LOR). Methods: To achieve this, population PBPK models were successfully developed and validated using multiple clinical pharmacokinetics (PK) and drug-drug interaction (DDI) studies, both in healthy subjects and patients. Results: The prediction-to-observation ratios for plasma AUC, Cmax, and Ctrough in heathy subjects and patients ranged between 0.5 and 2.0. In addition, PK profiles of CRI, ALE, and LOR in CSF aligned well with observed data. Moreover, the AUC and Cmax ratios of the three inhibitors when co-administered with CYP3A4 inhibitors/inducers also matched with clinically observed values. Utilizing PK thresholds for effective plasma Ctrough and AO values on wild-type and four ALK mutations in plasma and CSF, PBPK models were then combined with the mean and 95% confidence interval to predict optimal dosing regimens. Conclusions: Overall, these PBPK models provide valuable insights into determining appropriate dosing regimens for the three ALK inhibitors, understanding their effectiveness in brain metastasis therapy, and analyzing the underlying mechanisms of on-target resistance.

3.
Can J Infect Dis Med Microbiol ; 2022: 1338188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340919

RESUMO

Background: Pancreatic cancer patients were particularly predisposed to develop Escherichia coli (E. coli) bloodstream infection (BSI); however, little information is currently available. We set out to find E. coli BSI's risk factors in pancreatic cancer to provide valuable experience. Methods: We retrospectively analyzed the clinical data of pancreatic cancer patients (31 cases with E. coli BSI and 93 cases without BSI) by a case-control study. SPSS 17.0 was adopted to perform univariate and multivariate analyses. Bacterial resistance analysis was performed by Whonet 5.6. Results: Hospitalization days ≥7 days, number of admissions ≥2 times, surgery, chemotherapy, the type of antibiotics used ≥2 species, albumin<40.0 g/L, and prealbumin < 0.2 g/L were the potential risk factors for pancreatic cancer patients with E. coli BSI (P < 0.1). Multivariate logistic regression showed hospitalization days ≥7 days (OR = 11.196, 95% CI = 0.024-0.333, P < 0.001), surgery (OR = 32.053, 95% CI = 0.007-0.137, P < 0.001), and chemotherapy (OR = 6.174, 95% CI = 0.038-0.688, P=0.014) were the independent risk factors for E. coli BSI of pancreatic cancer patients. E. coli resistant to carbapenems was rare; they were susceptible to cephamycin and piperacillin/tazobactam. The 90-day mortality rate of the infected group was significantly higher than the control group (41.9% versus 8.6%, P < 0.001). Conclusions: Hospitalization days ≥7 days, surgery, and chemotherapy are the independent risk factors for E. coli BSI of pancreatic cancer patients, which allows us to identify patients at potential risk and perform preventive treatment in time.

4.
World J Surg Oncol ; 19(1): 228, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348726

RESUMO

PURPOSES: The purposes of this study were to assess the correlation between the plasma level of Hsp90α and the clinicopathological characteristics of patients with liver cancer and compare the diagnostic efficacy of Hsp90α, AFP, CEA, and CA199 in HCC. EXPERIMENTAL DESIGN: A total of 200 individuals, including 140 patients with liver cancer or benign liver diseases and 60 healthy people, were enrolled for quantitative measurement of plasma Hsp90α by ELISA. RESULTS: The plasma level of Hsp90α was significantly different between patients with liver cancer or benign liver diseases and healthy controls (P < 0.001). The sensitivity, specificity, and AUC (95% CI) of Hsp90α were 93.2%, 85.4%, and 0.931% (0.891-0.972%), respectively, when Hsp90α was applied to differentiate liver cancer patients and healthy controls. Significant positive correlations between the plasma Hsp90α level and clinicopathological characteristics such as the history of basic liver disease (P = 0.038), active stage of hepatitis (P = 0.039), Child-Pugh score (P < 0.001), size of focal liver lesions (P = 0.004), and extrahepatic metastasis (P < 0.001) were observed. AFP + Hsp90α was the best combination strategy for the auxiliary diagnosis of HCC, with a sensitivity of 95.7%, a specificity of 97.5%, and an AUC of 0.990 (0.976-1.000). The level of plasma Hsp90α decreased significantly (P < 0.001) after resection of tumor tissue. CONCLUSIONS: This study demonstrated that plasma Hsp90α levels are useful as a diagnostic biomarker in liver cancer and may predict the responses of patients with liver cancer to surgery. Some clinicopathological characteristics could affect the plasma Hsp90α levels.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais , Proteínas de Choque Térmico HSP90 , Humanos , Neoplasias Hepáticas/diagnóstico , Prognóstico
5.
Cancer Manag Res ; 13: 3675-3683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994808

RESUMO

BACKGROUND: Pancreatic cancer (PC) is one of the worst prognoses amongst all malignant diseases. It is therefore of great significance to identify biomarkers with predictive clinical value for the prognosis and recurrence of PC. METHODS: In our study, enzyme-linked immunosorbent assays (ELISA) were used to detect the expression of Exo-EphA2 in the serum of PC patients and controls. Kaplan-Meier curve and Cox regression analyses were used to evaluate the prognostic value of Exo-EphA2 expression in patients with primary and recurrent PC. RESULTS: The level of serum Exo-EphA2 was significantly higher in the PC group when compared to that of the control group. High expression of Exo-EphA2 in PC was associated with shorter overall survival (OS) and proved to be a significant negative prognostic factor in the multivariate analysis (HR = 1.04, 95% CI: 1.00-1.09, P <0.001). Additionally, we found that the level of serum Exo-EphA2 in recurrent PC patients (first recurrence < 12 months) was positively correlated with the level of Exo-EphA2 at primary diagnosis. Multivariate analysis showed that a high expression of Exo-EphA2 in recurrent PC was associated with shorter recurrence-free survival (RFS) (HR = 1.41, 95% CI: 1.10-1.70, P < 0.001). CONCLUSION: High expression of serum Exo-EphA2 represents a novel biomarker for a poor prognosis in PC patients.

6.
BMC Cancer ; 21(1): 401, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33849479

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors of the digestive system and has high morbidity and mortality rates. It is essential to search new biomarkers to improve the accuracy of early HCC diagnosis. Therefore, we evaluated the diagnostic value of prothrombin induced by vitamin K deficiency or antagonist- II (PIVKA-II) as a potential biomarker that complements α-fetoprotein (AFP) in HCC by detecting the serum PIVKA-II levels. METHODS: Serum PIVKA-II levels were compared in 168 HCC patients, 150 benign liver disease patients and 153 healthy controls to investigate the PIVKA-II potential to be a HCC biomarker. Receiver operating characteristic curve (ROC) analysis was used to evaluate the value of PIVKA-II in the diagnosis of HCC and its complementary role of AFP. The correlation between serum PIVKA-II levels and clinicopathological characteristics was analyzed to study the value of PIVKA-II in assessing HCC progression and prognosis. Finally, the ability of PIVKA-II in assessing the surgical treatment effects of HCC was studied by comparing the pre- and post-operative serum PIVKA-II levels in 89 HCC patients. RESULTS: Serum PIVKA-II levels in HCC patients were significantly higher than that in patients with benign liver disease and healthy controls. The PIVKA-II performance in the diagnosing HCC as an individual biomarker was remarkable. The combined detection of PIVKA-II and AFP improved the diagnostic efficiency of HCC. PIVKA-II retained significant diagnosis capabilities for AFP-negative HCC patients. Significant correlations were found between PIVKA-II expression levels and some clinicopathological characteristics, including tumor size, tumor stage, tumor metastasis, differentiation degree and complications. PIVKA-II expression obviously decreased after surgical resection. CONCLUSIONS: PIVKA-II is a promising serum biomarker for the HCC diagnosis that can be used as a supplement for AFP. The combined diagnosis of the two markers greatly improved the diagnostic efficiency of HCC. The PIVKA-II levels in HCC patients were widely associated with clinicopathological characteristics representing tumor cell dissemination and/or poor prognosis. PIVKA-II can be used to evaluate the curative effects of HCC resection.


Assuntos
Biomarcadores Tumorais , Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Precursores de Proteínas/sangue , alfa-Fetoproteínas , Carcinoma Hepatocelular/terapia , Gerenciamento Clínico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Biópsia Líquida , Neoplasias Hepáticas/terapia , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Protrombina , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
7.
ACS Nano ; 14(11): 15983-15991, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33136367

RESUMO

Various mechanisms of electrical generation of spin polarization in nonmagnetic materials have been a subject of broad interest for their underlying physics and device potential in spintronics. One such scheme is chirality-induced spin selectivity (CISS), with which structural chirality leads to different electric conductivities for electrons of opposite spins. The resulting effect of spin filtering has been reported for a number of chiral molecules assembled on different surfaces. However, the microscopic origin and transport mechanisms remain controversial. In particular, the fundamental Onsager relation was argued to preclude linear-response detection of CISS by a ferromagnet. Here, we report definitive observation of CISS-induced magnetoconductance in vertical heterojunctions of (Ga,Mn)As/AHPA-L molecules/Au, directly verifying spin filtering by the AHPA-L molecules via spin detection by the (Ga,Mn)As. The pronounced and robust magnetoconductance signals resulting from the use of a magnetic semiconductor enable a rigorous examination of its bias dependence, which shows both linear- and nonlinear-response components. The definitive identification of the linear-response CISS-induced two-terminal spin-valve effect places an important constraint for a viable theory of CISS and its device manifestations. The results present a promising route to spin injection and detection in semiconductors without using any magnetic material.

8.
Mol Med Rep ; 22(4): 2941-2947, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32945400

RESUMO

Pancreatic cancer (PC) is the fourth most common cause of cancer­related mortality worldwide and is characterized by high invasiveness and early metastasis. To identify novel diagnostic markers, the present study aimed to understand the mechanism underlying PC progression. The present study demonstrated that exosomes derived from the highly metastatic Panc­1 PC cell line were internalized by a low metastatic cell line, resulting in increased migration of the latter. Proteomics analysis further revealed that the receptor tyrosine kinase Eph receptor A2 (EphA2) was overexpressed in the Panc­1 exosomes, and these Exo_EphA2 had the ability to transfer metastatic potential to recipient cells. Consistent with this, circulating Exo_EphA2 levels were higher in patients with PC compared with healthy controls. Taken together, these results indicated that Exo_EphA2 acts an oncogene in PC and is a potential tumor maker for PC diagnosis.


Assuntos
Movimento Celular/genética , Efrina-A2/sangue , Exossomos/metabolismo , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Adulto , Idoso , Biomarcadores Tumorais/sangue , Linhagem Celular Tumoral , Progressão da Doença , Efrina-A2/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Oncogenes , Neoplasias Pancreáticas/patologia , Proteoma , Proteômica/métodos , Receptor EphA2 , Transdução Genética
9.
Nanotechnology ; 28(3): 035707, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-27966461

RESUMO

Germanium nanocrystals (Ge-ncs) were synthesized by implantation of Ge+ ions into the fused silica, followed by a thermal annealing at 1000 °C. High-resolution transmission electron microscopy was employed to characterize both the morphology of the formed Ge-ncs and the evolution of their depth-distribution as a function of annealing durations. The formation of nanocavities in the vicinity of nanocrystal/SiO2 interface is evidenced, as well as their influence on the release of the compressive stress exerted on Ge-ncs by surrounding SiO2. Some Ge-ncs are found inside nanocavities, and can move into the implanted layer through a nanocavity-assisted diffusion mechanism. This finding sheds light on a new process that can explain the non-uniformity of the Ge-nanocrystal spatial distribution.

10.
Phys Chem Chem Phys ; 18(40): 27967-27975, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27711427

RESUMO

The photocatalytic mechanism of a Cu2O/CuO hybrid system is disclosed in detail by density functional theory (DFT) calculations. The synergistic relationship of the two counterparts is confirmed by hydrogen peroxide (H2O2) formation on the CuO nanowires and dissociation on the Cu2O nanoparticles; this enables the system to self-sufficiently produce hydroxyl radicals, which is highly efficient in the photocatalytic degradation of methyl orange. The exposed surfaces are found to be crucial in the cooperative photocatalytic system, especially the Cu2O(111) surface, in the dissociation of H2O2. The distinct positions of the conduction band minimum and valence band maximum for CuO and Cu2O and synergic surface reactions enable the effective utilization of the electrons and holes generated by visible-light irradiation. Our results will contribute to a greater understanding of the specific mechanism of photodegradation catalyzed by Cu2O/CuO heterostructures, which may lead to promising directions in structure optimization for photocatalysts with high photocatalytic efficiency.

11.
Nanotechnology ; 27(29): 295703, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27285480

RESUMO

Bicrystalline α-Fe2O3 nanoblades (NBs) synthesized by thermal oxidation of iron foils were reduced in vacuum, to study the effect of reduction treatment on microstructural changes and photocatalytic properties. After the vacuum reduction, most bicrystalline α-Fe2O3 NBs transform into single-layered NBs, which contain more defects such as oxygen vacancies, perfect dislocations and dense pores. By comparing the photodegradation capability of non-reduced and reduced α-Fe2O3 NBs over model dye rhodamine B (RhB) in the presence of hydrogen peroxide, we find that vacuum-reduction induced microstructural defects can significantly enhance the photocatalytic efficiency. Even after 10 cycles, the reduced α-Fe2O3 NBs still show a very high photocatalytic activity. Our results demonstrate that defect engineering is a powerful tool to enhance the photocatalytic performance of nanomaterials.

12.
Mol Biol Rep ; 41(3): 1373-83, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24413988

RESUMO

Bone morphogenetic proteins (BMPs), which belong to the transforming growth factor-ß superfamily, regulate a wide range of cellular responses including cell proliferation, differentiation, adhesion, migration, and apoptosis. BMP9, the latest BMP to be discovered, is reportedly expressed in a variety of human carcinoma cell lines, but the role of BMP9 in breast cancer has not been fully clarified. In a previous study, BMP9 was found to inhibit the growth, migration, and invasiveness of MDA-MB-231 breast cancer cells. In the current study, the effect of BMP9 on the bone metastasis of breast cancer cells was investigated. After absent or low expression of BMP9 was detected in the MDA-MB-231 breast cancer cells and breast non-tumor adjacent tissues using Western blot and immunohistochemistry, In our previous study, BMP9 could inhibit the proliferation and invasiveness of breast cancer cells MDA-MB-231 in vitro and in vivo. This paper shows that BMP9 inhibit the bone metastasis of breast cancer cells by activating the BMP/Smad signaling pathway and downregulating connective tissue growth factor (CTGF); however, when CTGF expression was maintained, the inhibitory effect of BMP9 on the MDA-MB-231 cells was abolished. Together, these observations indicate that BMP9 is an important mediator of breast cancer bone metastasis and a potential therapeutic target for treating this deadly disease.


Assuntos
Apoptose/genética , Neoplasias da Mama/genética , Fator de Crescimento do Tecido Conjuntivo/biossíntese , Fatores de Diferenciação de Crescimento/metabolismo , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Fator de Crescimento do Tecido Conjuntivo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Fator 2 de Diferenciação de Crescimento , Fatores de Diferenciação de Crescimento/genética , Humanos
13.
J Cancer Res Clin Oncol ; 137(11): 1687-96, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21892652

RESUMO

BACKGROUND: Transforming growth factor-ß (TGF-ß) is known to promote tumor proliferation, migration, invasion, and metastasis. Bone morphogenetic proteins (BMPs) are members of the TGF-ß superfamily. Several BMPs (BMP2 and BMP7) can enhance the invasion and bone metastasis of breast cancer cells. The function of BMP9, the latest discovered and most powerful osteogenetic factor, in breast cancer has not been fully elucidated. METHODS: BMP9 expression in twenty-three breast cancer patients and three breast cancer cell line types was detected by reverse transcriptase polymerase chain reaction. Changes in proliferation, apoptosis, invasion, and migration in the recombinant MDA-MB-231/BMP9 cells were detected using various assays. The assays were MTT, flow cytometry, colony forming, cell wounding, and transwell invasion. Proliferating cell nuclear antigen and terminal deoxynucleotidy transferase biotin-dUTP nick end labeling staining methods were conducted to detect whether BMP9 affected proliferation and apoptosis in xenogenic mouse models. RESULTS: Twenty-one of the twenty-three breast cancer patients had amplified BMP9 mRNA transcripts in adjacent non-tumor tissues, although BMP9 was observed in the breast cancer tissue of two patients, its expression was higher in the adjacent non-tumor tissues. BMP9 overexpression inhibited the proliferation, migration, and invasion, as well as induced the apoptosis of the breast cancer cell line MDA-MB-231 in vitro. BMP9 also inhibited tumor growth and induced apoptosis significantly in the xenogenic mouse models. CONCLUSIONS: Decreased BMP9 expression is associated with the elevated proliferation and migration of human breast cancer. BMP9 can inhibit the growth, invasion, and migration of breast cancer cells in vitro and in vivo. BMP9 is a putative tumor suppressor in breast cancer.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células , Fatores de Diferenciação de Crescimento/genética , Animais , Apoptose , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Feminino , Fator 2 de Diferenciação de Crescimento , Fatores de Diferenciação de Crescimento/metabolismo , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica , Transplante de Neoplasias , RNA Mensageiro/metabolismo , Transplante Heterólogo
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