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1.
Proc Natl Acad Sci U S A ; 120(21): e2304081120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186828

RESUMO

Chemotherapy typically destroys the tumor mass but rarely eradicates the cancer stem cells (CSCs) that can drive metastatic recurrence. A key current challenge is finding ways to eradicate CSCs and suppress their characteristics. Here, we report a prodrug, Nic-A, created by combining a carbonic anhydrase IX (CAIX) inhibitor, acetazolamide, with a signal transducer and transcriptional activator 3 (STAT3) inhibitor, niclosamide. Nic-A was designed to target triple-negative breast cancer (TNBC) CSCs and was found to inhibit both proliferating TNBC cells and CSCs via STAT3 dysregulation and suppression of CSC-like properties. Its use leads to a decrease in aldehyde dehydrogenase 1 activity, CD44high/CD24low stem-like subpopulations, and tumor spheroid-forming ability. TNBC xenograft tumors treated with Nic-A exhibited decreased angiogenesis and tumor growth, as well as decreased Ki-67 expression and increased apoptosis. In addition, distant metastases were suppressed in TNBC allografts derived from a CSC-enriched population. This study thus highlights a potential strategy for addressing CSC-based cancer recurrence.


Assuntos
Pró-Fármacos , Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/metabolismo , Niclosamida/farmacologia , Niclosamida/metabolismo , Niclosamida/uso terapêutico , Pró-Fármacos/uso terapêutico , Recidiva Local de Neoplasia/patologia , Fatores de Transcrição/metabolismo , Células-Tronco Neoplásicas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Cell Mol Life Sci ; 80(5): 132, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37185776

RESUMO

We sought to investigate the utility of ebastine (EBA), a second-generation antihistamine with potent anti-metastatic properties, in the context of breast cancer stem cell (BCSC)-suppression in triple-negative breast cancer (TNBC). EBA binds to the tyrosine kinase domain of focal adhesion kinase (FAK), blocking phosphorylation at the Y397 and Y576/577 residues. FAK-mediated JAK2/STAT3 and MEK/ERK signaling was attenuated after EBA challenge in vitro and in vivo. EBA treatment induced apoptosis and a sharp decline in the expression of the BCSC markers ALDH1, CD44 and CD49f, suggesting that EBA targets BCSC-like cell populations while reducing tumor bulk. EBA administration significantly impeded BCSC-enriched tumor burden, angiogenesis and distant metastasis while reducing MMP-2/-9 levels in circulating blood in vivo. Our findings suggest that EBA may represent an effective therapeutic for the simultaneous targeting of JAK2/STAT3 and MEK/ERK for the treatment of molecularly heterogeneous TNBC with divergent profiles. Further investigation of EBA as an anti-metastatic agent for the treatment of TNBC is warranted.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Proteína-Tirosina Quinases de Adesão Focal , Neoplasias de Mama Triplo Negativas/metabolismo , Linhagem Celular Tumoral , Quinases de Proteína Quinase Ativadas por Mitógeno , Proliferação de Células
3.
Sensors (Basel) ; 23(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005536

RESUMO

An automotive 2.1 µm CMOS image sensor has been developed with a full-depth deep trench isolation and an advanced readout circuit technology. To achieve a high dynamic range, we employ a sub-pixel structure featuring a high conversion gain of a large photodiode and a lateral overflow of a small photodiode connected to an in-pixel storage capacitor. With the sensitivity ratio of 10, the expanded dynamic range could reach 120 dB at 85 °C by realizing a low random noise of 0.83 e- and a high overflow capacity of 210 ke-. An over 25 dB signal-to-noise ratio is achieved during HDR image synthesis by increasing the full-well capacity of the small photodiode up to 10,000 e- and suppressing the floating diffusion leakage current at 105 °C.

4.
Cancer Cell Int ; 22(1): 289, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127671

RESUMO

BACKGROUND: The emergence of de novo or intrinsic trastuzumab resistance is exceedingly high in breast cancer that is HER2 positive and correlates with an abundant cancer stem cell (CSC)-like population. We sought to examine the capacity of ß-escin, an anti-inflammatory drug, to address trastuzumab resistance in HER2-positive breast cancer cells. METHODS: The effect of ß-escin on trastuzumab-resistant and -sensitive cell lines in vitro was evaluated for apoptosis, expression of HER2 family members, and impact on CSC-like properties. An in vivo model of trastuzumab-resistant JIMT-1 was used to examine the efficacy and toxicity of ß-escin. RESULTS: ß-escin induced mitochondrial-mediated apoptosis accompanied by reactive oxygen species (ROS) production and increased active p18Bax fragmentation, leading to caspase-3/-7 activation. Attenuation of CSC-related features by ß-escin challenge was accompanied by marked reductions in CD44high/CD24low stem-like cells and aldehyde dehydrogenase 1 (ALDH1) activity as well as hindrance of mammosphere formation. ß-escin administration also significantly retarded tumor growth and angiogenesis in a trastuzumab-resistant JIMT-1 xenograft model via downregulation of CSC-associated markers and intracellular domain HER2. Importantly, ß-escin selectively inhibited malignant cells and was less toxic to normal mammary cells, and no toxic effects were found in liver and kidney function in animals. CONCLUSIONS: Taken together, our findings highlight ß-escin as a promising candidate for the treatment of trastuzumab-resistant HER2-positive breast cancers.

5.
Int J Cancer ; 149(8): 1585-1592, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34213778

RESUMO

Incorporating dual human epidermal growth factor receptor 2 (HER2) blockade into neoadjuvant systemic therapy (NST) led to higher response in patients with HER2-positive breast cancer. However, axillary response to treatment regimens, including single or dual HER2 blockade, in patients with clinically node-positive breast cancer remains uncertain. Our study aimed to examine the pathologic axillary response according to the type of NST, that is, single or dual HER2 blockade. In our study, 546 patients with clinically node-positive, HER2-positive breast cancer who received NST followed by axillary surgery were retrospectively selected and divided into three groups: chemotherapy alone, chemotherapy + trastuzumab and chemotherapy + trastuzumab with pertuzumab. The primary outcome was the axillary pathologic complete response (pCR). Among 471 patients undergoing axillary lymph node dissection, the axillary pCR rates were 43.5%, 74.5% and 68.8% in patients who received chemotherapy alone, chemotherapy + trastuzumab and chemotherapy + trastuzumab with pertuzumab, respectively. There was no difference in axillary pCR rates between patients who received single or dual HER2 blockade (P = .379). Among patients receiving chemotherapy + trastuzumab, patients without breast pCR had the greatest risk for residual axillary metastases (relative risk, 9.8; 95% confidence interval, 3.2-14.9; P < .0001). In conclusion, adding trastuzumab to chemotherapy increased the axillary pCR rate in patients with clinically node-positive, HER2-positive breast cancer; furthermore, dual HER2-blockade with trastuzumab and pertuzumab did not elevate the axillary response compared with trastuzumab alone. Breast pCR could be a strong predictor for axillary pCR in clinically node-positive patients treated with HER2-targeting therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linfonodos/patologia , Terapia Neoadjuvante/métodos , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Axila , Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Linfonodos/metabolismo , Metástase Linfática , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Trastuzumab/administração & dosagem
6.
J Ethn Subst Abuse ; : 1-16, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33413042

RESUMO

Cultural capital is a known factor supporting success in substance use disorder (SUD) treatment. We investigated Asian American and Pacific Islander (AAPI) State population metrics in relation to SUD treatment completion for US clients from 2006-2017 (N = 5,404,374). Metrics that may signify greater available cultural capital were State AAPI Percentage, State AAPI Percent Change, and State AAPI Population. AAPI Percentage, AAPI Percent Change were positively associated, while AAPI Population was negatively associated with treatment completion (p < 0.001). Findings suggest treatment agencies in areas with low AAPI densities may improve outcomes by supporting AAPI community and cultural social networks.

7.
Mol Cancer ; 19(1): 161, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33218356

RESUMO

Trastuzumab resistance in HER2-positive breast cancer is associated with a poorer prognosis. HSP90 is thought to play a major role in such resistance, but N-terminal inhibitors of this target have had little success. We sought to investigate the utility of NCT-547, a novel, rationally-designed C-terminal HSP90 inhibitor in the context of overcoming trastuzumab resistance. NCT-547 treatment significantly induced apoptosis without triggering the heat shock response (HSR), accompanied by caspase-3/- 7 activation in both trastuzumab-sensitive and -resistant cells. NCT-547 effectively promoted the degradation of full-length HER2 and truncated p95HER2, while also attenuating hetero-dimerization of HER2 family members. The impairment of cancer stem-like traits was observed with reductions in ALDH1 activity, the CD24low/CD44high subpopulation, and mammosphere formation in vitro and in vivo. NCT-547 was an effective inhibitor of tumor growth and angiogenesis, and no toxic outcomes were found in initial hepatic and renal analysis. Our findings suggest that NCT-547 may have applications in addressing trastuzumab resistance in HER2-positive breast cancer.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Trastuzumab/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos Imunológicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Humanos , Camundongos , Células-Tronco Neoplásicas , Domínios Proteicos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Breast Cancer Res Treat ; 184(3): 797-803, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32909180

RESUMO

PURPOSE: Insertion of radiopaque markers is helpful for tumor localization in patients receiving neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS). The aim of this retrospective study was to investigate the pathologic margin status in patients with single or double marker insertion. METHODS: We reviewed the records of 130 patients with marker insertion prior to NAC followed by BCS from January 2016 to September 2019. Under ultrasonography guidance, single or double markers were inserted to localize a tumor in the breast. The incidence of additional resection after frozen biopsy and re-excision after permanent pathologic diagnosis was analyzed. RESULTS: In a total of 130 patients, 104 had a single marker in the center of the tumor and 26 had double markers at the periphery of the tumor before NAC. Among 69 patients with residual invasive tumors after NAC, there was no difference in the additional resection rate after frozen biopsy (single vs. double markers; 14.3% vs. 38.5%, P = .059) or the re-excision rate after final pathologic diagnosis (0% vs. 7.7%, P = .188). After propensity score matching for tumor size and subtypes, the two groups showed no differences in the additional resection rate after frozen biopsy (7.7% vs. 19.2%, P = .139) or the re-excision rate (0% vs. 3.8%, P = .308). After a median follow-up of 19 months (range 8-48 months), local recurrence-free survival did not differ between the two groups (log-rank P = .456). CONCLUSIONS: Number of inserted markers for tumor localization did not affect the pathologic margin status after BCS.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Margens de Excisão , Mastectomia Segmentar , Recidiva Local de Neoplasia , Estudos Retrospectivos
9.
Eur Radiol ; 30(2): 789-797, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696293

RESUMO

OBJECTIVE: To develop a nomogram and validate its use for the intraoperative evaluation of nodal metastasis using shear-wave elastography (SWE) elasticity values and nodal size METHODS: We constructed a nomogram to predict metastasis using ex vivo SWE values and ultrasound features of 228 axillary LNs from fifty-five patients. We validated its use in an independent cohort comprising 80 patients. In the validation cohort, a total of 217 sentinel LNs were included. RESULTS: We developed the nomogram using the nodal size and elasticity values of the development cohort to predict LN metastasis; the area under the curve (AUC) was 0.856 (95% confidence interval (CI), 0.783-0.929). In the validation cohort, 15 (7%) LNs were metastatic, and 202 (93%) were non-metastatic. The mean stiffness (23.54 and 10.41 kPa, p = 0.005) and elasticity ratio (3.24 and 1.49, p = 0.028) were significantly higher in the metastatic LNs than those in the non-metastatic LNs. However, the mean size of the metastatic LNs was not significantly larger than that of the non-metastatic LNs (8.70 mm vs 7.20 mm, respectively; p = 0.123). The AUC was 0.791 (95% CI, 0.668-0.915) in the validation cohort, and the calibration plots of the nomogram showed good agreement. CONCLUSIONS: We developed a well-validated nomogram to predict LN metastasis. This nomogram, mainly based on ex vivo SWE values, can help evaluate nodal metastasis during surgery. KEY POINTS: • A nomogram was developed based on axillary LN size and ex vivo SWE values such as mean stiffness and elasticity ratio to easily predict axillary LN metastasis during breast cancer surgery. • The constructed nomogram presented high predictive performance of sentinel LN metastasis with an independent cohort. • This nomogram can reduce unnecessary intraoperative frozen section which increases the surgical time and costs in breast cancer patients.


Assuntos
Neoplasias da Mama/cirurgia , Metástase Linfática/diagnóstico por imagem , Nomogramas , Adulto , Idoso , Área Sob a Curva , Axila , Neoplasias da Mama/patologia , Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Metástase Linfática/patologia , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Linfonodo Sentinela/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Adulto Jovem
10.
Bioorg Med Chem Lett ; 30(17): 127374, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738983

RESUMO

A series of O-substituted analogues of the B,C-ring truncated scaffold of deguelin were designed as C-terminal inhibitors of heat shock protein 90 (HSP90) and investigated as novel antiproliferative agents against HER2-positive breast cancer. Among the synthesized compounds, compound 80 exhibited significant inhibition in both trastuzumab-sensitive and trastuzumab-resistant breast cancer cells, whereas compound 80 did not show any cytotoxicity in normal cells. Compound 80 markedly downregulated the expression of the major client proteins of HSP90 in both cell types, indicating that the cytotoxicity of 80 in breast cancer cells is attributed to the destabilization and inactivation of HSP90 client proteins and that HSP90 inhibition represents a promising strategy to overcome trastuzumab resistance. A molecular docking study of 80 with the homology model of a HSP90 homodimer showed that 80 fit nicely in the C-terminal domain with a higher electrostatic complementary score than that of ATP.


Assuntos
Antineoplásicos/química , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Rotenona/análogos & derivados , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Simulação de Acoplamento Molecular , Rotenona/química , Rotenona/metabolismo , Rotenona/farmacologia , Relação Estrutura-Atividade
11.
Surg Endosc ; 30(2): 625-632, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26091990

RESUMO

BACKGROUND: Bleeding is a major complication following endoscopic resection (ER) of gastric mucosal lesions. We aimed to determine the risk factors for post-ER bleeding and their correlations according to the time elapsed since the procedure. METHODS: We retrospectively enrolled 670 lesions in 610 patients who underwent ER between March 2009 and December 2010. We classified these lesions into three types in accordance with the bleeding time, i.e., immediate bleeding (IB), early delayed bleeding (EDB), and late delayed bleeding (LDB). We analyzed the risk factors for each bleeding type according to baseline patient characteristics, procedure-related factors, and correlations between the occurrence of each bleeding type. RESULTS: There were 408 post-ER bleeding events in our study cohort: 302 IB events, 88 EDB events, and 18 LDB events. In multivariate analysis, a histologic finding of carcinoma and the resection time were significant predictors of IB (p < 0.001). Of the 302 IB events, 13.9% showed EDB. Additionally, LDB occurred in 2.4% of lesions with EDB and 4.6% of lesions without EDB. Similar to the IB group, of 368 lesions without IB, 12.5% showed EDB. In addition, LDB occurred in 2.2% of lesions with EDB and 1.2% of lesions without EDB. IB was associated with a higher risk of EDB (p < 0.001) and LDB (p < 0.001), whereas EDB was not related to an increased risk of LDB (p = 0.997). CONCLUSION: IB significantly increases the risk of EDB and LDB, but EDB does not increase the risk of LDB. Histologically confirmed carcinoma or a prolonged time for resection increases the risk of post-ER IB. We recommend careful follow-up approaches following ER of a gastric mucosal lesion in high-risk patients to prevent a potentially critical occurrence of delayed bleeding.


Assuntos
Carcinoma/cirurgia , Mucosa Gástrica/cirurgia , Gastroscopia/métodos , Hemorragia Pós-Operatória/epidemiologia , Neoplasias Gástricas/cirurgia , Idoso , Estudos de Coortes , Dissecação , Endoscopia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Duração da Cirurgia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
12.
Theranostics ; 14(6): 2442-2463, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646654

RESUMO

Rationale: Resistance to targeted therapies like trastuzumab remains a critical challenge for HER2-positive breast cancer patients. Despite the progress of several N-terminal HSP90 inhibitors in clinical trials, none have achieved approval for clinical use, primarily due to issues such as induction of the heat shock response (HSR), off-target effects, and unfavorable toxicity profiles. We sought to examine the effects of HVH-2930, a novel C-terminal HSP90 inhibitor, in overcoming trastuzumab resistance. Methods: The effect of HVH-2930 on trastuzumab-sensitive and -resistant cell lines in vitro was evaluated in terms of cell viability, expression of HSP90 client proteins, and impact on cancer stem cells. An in vivo model with trastuzumab-resistant JIMT-1 cells was used to examine the efficacy and toxicity of HVH-2930. Results: HVH-2930 was rationally designed to fit into the ATP-binding pocket interface cavity of the hHSP90 homodimer in the C-terminal domain of HSP90, stabilizing its open conformation and hindering ATP binding. HVH-2930 induces apoptosis without inducing the HSR but by specifically suppressing the HER2 signaling pathway. This occurs with the downregulation of HER2/p95HER2 and disruption of HER2 family member heterodimerization. Attenuation of cancer stem cell (CSC)-like properties was associated with the downregulation of stemness factors such as ALDH1, CD44, Nanog and Oct4. Furthermore, HVH-2930 administration inhibited angiogenesis and tumor growth in trastuzumab-resistant xenograft mice. A synergistic effect was observed when combining HVH-2930 and paclitaxel in JIMT-1 xenografts. Conclusion: Our findings highlight the potent efficacy of HVH-2930 in overcoming trastuzumab resistance in HER2-positive breast cancer. Further investigation is warranted to fully establish its therapeutic potential.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP90 , Receptor ErbB-2 , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Animais , Feminino , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Linhagem Celular Tumoral , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Camundongos Nus , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Antineoplásicos/farmacologia
13.
Foods ; 12(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37628105

RESUMO

The consumption of fresh produce is increasing due to its role in promoting a healthy and balanced diet. However, this trend is accompanied by increased foodborne disease cases associated with pathogens such as Escherichia, Listeria, and Salmonella. Previous studies provided evidence that the internalization of foodborne pathogens in fresh produce may be a potential contamination route and may pose a public health risk. This study investigates the combination effects of storage temperature and humidity on Salmonella internalization in six types of leafy greens (iceberg lettuce, romaine lettuce, red lettuce, green onion, spinach, and kale) during the storage stage. The results indicated that temperature plays a critical role in Salmonella internalization, with higher concentrations observed in samples stored at 25 °C compared to those stored at 7 °C. The mean concentration of internalized Salmonella in the iceberg lettuce sample was the highest and that in the green onion sample was the lowest (iceberg lettuce > red lettuce > romaine lettuce > spinach > kale > green onion). Mist conditions also had an impact on internalization. The group treated with mist showed an increase in Salmonella internalization of about 10-30% rather than the group without mist treatment. This research emphasizes the importance of understanding the factors influencing bacterial internalization in fresh produce and highlights the need for proper storage conditions to minimize the risk of contamination and ensure food safety.

14.
Polymers (Basel) ; 16(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38201709

RESUMO

We demonstrate a single-component hydrophilic photocrosslinkable copolymer system that incorporates all critical functionalities into one chain. This design allows for the creation of uniform functional organic coatings on a variety of substrates. The copolymers were composed of a poly(ethylene oxide)-containing monomer, a monomer that can release a primary amine upon UV light, and a monomer with reactive epoxide or cyclic dithiocarbonate with a primary amine. These copolymers are easily incorporated into the solution-casting process using polar solvents. Furthermore, the resulting coating can be readily stabilized through UV light-induced crosslinking, providing an advantage for controlling the surface properties of various substrates. The photocrosslinking capability further enables us to photolithographically define stable polymer domains in a desirable region. The resulting copolymer coatings were chemically versatile in immobilizing complex molecules by (i) post-crosslinking functionalization with the reactive groups on the surface and (ii) the formation of a composite coating by mixing varying amounts of a protein of interest, i.e., fish skin gelatin, which can form a uniform dual crosslinked network. The number of functionalization sites in a thin film could be controlled by tuning the composition of the copolymers. In photocrosslinking and subsequent functionalizations, we assessed the reactivity of the epoxide and cyclic dithiocarbonate with the generated primary amine. Moreover, the orthogonality of the possible reactions of the presented reactive functionalities in the crosslinked thin films with complex molecules is assessed. The resulting copolymer coatings were further utilized to define a hydrophobic surface or an active surface for the adhesion of biological objects.

15.
J Exp Clin Cancer Res ; 42(1): 292, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37924112

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is characterized by aggressive growth and a high propensity for recurrence and metastasis. Simultaneous overexpression of c-MET and EGFR in TNBC is associated with worse clinicopathological features and unfavorable outcomes. Although the development of new c-MET inhibitors and the emergence of 3rd-generation EGFR inhibitors represent promising treatment options, the high costs involved limit the accessibility of these drugs. In the present study, we sought to investigate the therapeutic potential of doxazosin (DOXA), a generic drug for benign prostate hyperplasia, in targeting TNBC. METHODS: The effect of DOXA on TNBC cell lines in vitro was evaluated in terms of cell viability, apoptosis, c-MET/EGFR signaling pathway, molecular docking studies and impact on cancer stem cell (CSC)-like properties. An in vivo metastatic model with CSCs was used to evaluate the efficacy of DOXA. RESULTS: DOXA exhibits notable anti-proliferative effects on TNBC cells by inducing apoptosis via caspase activation. Molecular docking studies revealed the direct interaction of DOXA with the tyrosine kinase domains of c-MET and EGFR. Consequently, DOXA disrupts important survival pathways including AKT, MEK/ERK, and JAK/STAT3, while suppressing CSC-like characteristics including CD44high/CD24low subpopulations, aldehyde dehydrogenase 1 (ALDH1) activity and formation of mammospheres. DOXA administration was found to suppress tumor growth, intra- and peri-tumoral angiogenesis and distant metastasis in an orthotopic allograft model with CSC-enriched populations. Furthermore, no toxic effects of DOXA were observed in hepatic or renal function. CONCLUSIONS: Our findings highlight the potential of DOXA as a therapeutic option for metastatic TNBC, warranting further investigation.


Assuntos
Doxazossina , Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Doxazossina/farmacologia , Doxazossina/uso terapêutico , Receptores ErbB/antagonistas & inibidores , Simulação de Acoplamento Molecular , Células-Tronco Neoplásicas/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
16.
Bioorg Med Chem ; 20(16): 4962-7, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22819942

RESUMO

A series of benzo-annulated derivatives of tryptanthrin were prepared and their optical and redox properties were studied. Tryptanthrin and its benzo-annulated derivatives showed selective inhibitory activity on topo I with an increase of activity on topo II by benzo-annulation on quinazolin-4(3H)-one moiety. Although the benzo-annulation on quinazolin-4(3H)-one ring did not affect significantly on the inhibitory activities against topo I and II, the benzoannulation on indolin-3-one ring affected the inhibitory activity very much especially by linear annulation. Cytotoxicities were not significantly changed upon benzoannulation, which were not directly related either to the inhibitory activities against topo I and II or to the reduction potentials.


Assuntos
Quinazolinas/síntese química , Quinazolinas/farmacologia , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase II/farmacologia , Animais , Bovinos , DNA/metabolismo , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Estrutura Molecular , Quinazolinas/química , Relação Estrutura-Atividade , Inibidores da Topoisomerase I/síntese química , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química
17.
Front Immunol ; 13: 907088, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720408

RESUMO

Aphis gossypii, commonly known as the cotton aphid, is a widely distributed pest of agricultural crops and acts as a vector for many serious plant viruses. Cotton aphid shows high resistance to chemical insecticides due to rapid rates of genetic diversity as a result of its short life cycle, seasonal migration, and host alteration. As an alternative, entomopathogenic fungi can be used to control cotton aphids in an environmentally sound manner. However, little is known about how cotton aphids respond to fungal infection. In this work, a new Beauveria bassiana strain JEF-544 (Bb JEF-544) was selected and isolated through bioassays with high virulence against cotton aphid. Early response of cotton aphid to Bb JEF-544 infection was analyzed at the transcriptome level. Infected aphids were collected two days after treatment at 25% lethal time (LT25), and total RNA of non-infected and Bb JEF-544-infected aphids was independently subjected to sequencing. Infected aphids showed significant up-regulation of the insect hormone biosynthesis pathway. Bursicon (Burs) and crustacean cardioactive peptide (CCAP) receptors involved in molting along with ecdysone synthesis were also strongly up-regulated in the aphid response to the fungal infection. In the immune response, melanization in the hemocoel was significantly up-regulated, while phagocytosis was less actively transcribed. In conclusion, cotton aphids protect themselves from Bb JEF-544 infection by activating the immune response including melanization and insect molting hormones to shed infected cuticles. In addition to describing the initial stages of Bb JEF-544 infection at the transcriptome level, this work provides potential treatment targets and insight into how fungal isolates can effectively be used to control this serious aphid species.


Assuntos
Afídeos , Beauveria , Animais , Mecanismos de Defesa , Insetos , Virulência
18.
Sci Rep ; 12(1): 11569, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798931

RESUMO

To investigate the response of the general circulation and global transport of heat through both atmosphere and ocean to two-types of carbon dioxide removal scenario, we performed an earth system model experiment in which we imposed a pulse-type quadrupling of CO2 forcing for 50 years and a gradual peak-and-decline of four-time CO2 forcing. We found that the results from two experiments are qualitatively similar to each other. During the forcing-on period, a dominant warming in the upper troposphere over the tropics and on the surface at high latitudes led to a slowdown in the Hadley circulation, but the poleward atmospheric energy transport was enhanced due to an increase in specific humidity. This counteracted the reduction in poleward oceanic energy transport owing to the suppression of the meridional overturning circulation in both Hemispheres. After returning the original CO2 level, the hemispheric thermal contrast was reversed, causing a southward shift of the intertropical convergence zone. To reduce the hemispheric thermal contrast, the northward energy transports in the atmosphere and ocean surface were enhanced while further weakening of the global-scale Atlantic meridional overturning circulation led to southward energy transport in the deep ocean.

19.
J Breast Cancer ; 25(6): 485-499, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36479600

RESUMO

PURPOSE: We investigated the treatment response and prognosis using the neutrophil-to-lymphocyte ratio (NLR) and standardized uptake value (SUV) of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in neoadjuvant settings. METHODS: Baseline NLR and maximum SUV (SUVmax) were retrospectively analyzed in 273 females with breast cancer who received neoadjuvant chemotherapy followed by surgery. Of these, 101 patients underwent 18F-FDG PET after 3-4 neoadjuvant chemotherapy cycles, which allowed the measurement of ΔSUVmax, an early reduction in SUVmax. NLR and early SUVmax reduction (ΔSUVmax) were classified as low and high, respectively, relative to the median values. RESULTS: The mean NLR was lower, and the mean ΔSUVmax was higher in patients with pathologic complete response (pCR) than in those with residual tumors. The ΔSUVmax was an independent variable associated with pCR. Furthermore, the high NLR group had poor recurrence-free survival (RFS) and overall survival. Among patients with ΔSUVmax data, high NLR (adjusted hazard ratio, 2.82; 95% confidence intervals [CI], 1.26-6.28; P = 0.016) and low ΔSUVmax (adjusted hazard ratio, 2.39; 95% CI, 1.07-5.34; P = 0.037) were independent prognostic factors for poor RFS. The categorization of the patients into four groups according to the combination of NLR and ΔSUVmax showed that patients with high NLR and low ΔSUVmax had significantly poorer RFS. CONCLUSION: Baseline NLR and ΔSUVmax were significantly associated with the prognosis of patients with breast cancer who received neoadjuvant chemotherapy. These results suggest that metabolic non-responders with defective immune systems have worse survival outcomes.

20.
Front Immunol ; 13: 875083, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874766

RESUMO

Toll-like receptors (TLRs) play critical roles in the first line of host defense against pathogens through recognition of pathogen-associated molecular patterns and initiation of the innate immune responses. The proper localization of TLRs in specific subcellular compartments is crucial for their ligand recognition and downstream signaling to ensure appropriate responses against pathogens while avoiding erroneous or excessive activation. Several TLRs, including TLR7 and TLR9 but not TLR4, depend on UNC93B1 for their proper intracellular localization and signaling. Accumulating evidence suggest that UNC93B1 differentially regulates its various client TLRs, but the specific mechanisms by which UNC93B1 controls individual TLRs are not well understood. Protein N-glycosylation is one of the most frequent and important post-translational modification that occurs in membrane-localized or secreted proteins. UNC93B1 was previously shown to be glycosylated at Asn251 and Asn272 residues. In this study, we investigated whether N-glycosylation of UNC93B1 affects its function by comparing wild type and glycosylation-defective mutant UNC93B1 proteins. It was found that glycosylation of Asn251 and Asn272 residues can occur independently of each other and mutation of neither N251Q or N272Q in UNC93B1 altered expression and localization of UNC93B1 and TLR9. In contrast, CpG DNA-stimulated TLR9 signaling was severely inhibited in cells expressing UNC93B1(N272Q), but not in cells with UNC93B1(N251Q). Further, it was found that glycosylation at Asn272 of UNC93B1 is essential for the recruitment of MyD88 to TLR9 and the subsequent downstream signaling. On the other hand, the defective glycosylation at Asn272 did not affect TLR7 signaling. Collectively, these data demonstrate that the glycosylation at a specific asparagine residue of UNC93B1 is required for TLR9 signaling and the glycosylation status of UNC93B1 differently affects activation of TLR7 and TLR9.


Assuntos
Receptor 7 Toll-Like , Receptor Toll-Like 9 , Asparagina/metabolismo , Glicosilação , Humanos , Proteínas de Membrana Transportadoras/genética , Receptor 7 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Receptores Toll-Like/metabolismo
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