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1.
Nanoscale ; 13(35): 14879-14899, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533177

RESUMO

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag2S quantum dots (AS-2MPA) optically trackable in near-infrared (NIR), conjugated with endothelial growth factor receptor (EGFR) targeting Cetuximab (Cet) and loaded with ALA for PDT monotherapy or ALA/5-fluorouracil (5FU) for the combination therapy are proposed for enhanced treatment of EGFR(+) CRC. AS-2MPA-Cet exhibited excellent targeting of the high EGFR expressing cells and showed a strong intracellular signal for NIR optical detection in a comparative study performed on SW480, HCT116, and HT29 cells, which exhibit high, medium and low EGFR expression, respectively. Targeting provided enhanced uptake of the ALA loaded nanoparticles by strong EGFR expressing cells and formation of higher levels of PpIX. Cells also differ in their efficiency to convert ALA to PpIX, and SW480 was the best, followed by HT29, while HCT116 was determined as unsuitable for ALA-PDT. The therapeutic efficacy was evaluated in 2D cell cultures and 3D spheroids of SW480 and HT29 cells using AS-2MPA with either electrostatically loaded, hydrazone or amide linked ALA to achieve different levels of pH or enzyme sensitive release. Most effective phototoxicity was observed in SW480 cells using AS-2MPA-ALA-electrostatic-Cet due to enhanced uptake of the particles, fast ALA release and effective ALA-to-PpIX conversion. Targeted delivery reduced the effective ALA concentration significantly which was further reduced with codelivery of 5FU. Delivery of ALA via covalent linkages was also effective for PDT, but required a longer incubation time for the release of ALA in therapeutic doses. Phototoxicity was correlated with high levels of reactive oxygen species (ROS) and apoptotic/necrotic cell death. Hence, both AS-2MPA-ALA-Cet based PDT and AS-2MPA-ALA-Cet-5FU based chemo/PDT combination therapy coupled with strong NIR tracking of the nanoparticles demonstrate an exceptional therapeutic effect on CRC cells and excellent potential for synergistic multistage tumour targeting therapy.


Assuntos
Neoplasias Colorretais , Fotoquimioterapia , Pontos Quânticos , Ácido Aminolevulínico/farmacologia , Linhagem Celular Tumoral , Cetuximab/farmacologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico , Humanos , Imagem Óptica , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas
2.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34521767

RESUMO

Early stages of colorectal cancer (CRC) development are characterized by a complex rewiring of transcriptional networks resulting in changes in the expression of multiple genes. Here, we demonstrate that the deletion of a poorly studied tetraspanin protein Tspan6 in Apcmin/+ mice, a well-established model for premalignant CRC, resulted in increased incidence of adenoma formation and tumor size. We demonstrate that the effect of Tspan6 deletion results in the activation of EGF-dependent signaling pathways through increased production of the transmembrane form of TGF-α (tmTGF-α) associated with extracellular vesicles. This pathway is modulated by an adaptor protein syntenin-1, which physically links Tspan6 and tmTGF-α. In support of this, the expression of Tspan6 is frequently decreased or lost in CRC, and this correlates with poor survival. Furthermore, the analysis of samples from the epidermal growth factor receptor (EGFR)-targeting clinical trial (COIN trial) has shown that the expression of Tspan6 in CRC correlated with better patient responses to EGFR-targeted therapy involving Cetuximab. Importantly, Tspan6-positive patients with tumors in the proximal colon (right-sided) and those with KRAS mutations had a better response to Cetuximab than the patients that expressed low Tspan6 levels. These results identify Tspan6 as a regulator of CRC development and a potential predictive marker for EGFR-targeted therapies in CRC beyond RAS pathway mutations.


Assuntos
Biomarcadores Tumorais/metabolismo , Cetuximab/farmacologia , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Tetraspaninas/metabolismo , Tetraspaninas/fisiologia , Animais , Antineoplásicos Imunológicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prognóstico , Taxa de Sobrevida , Tetraspaninas/genética , Células Tumorais Cultivadas
3.
Integr Cancer Ther ; 20: 15347354211045349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34590499

RESUMO

Treatment for advanced gastric cancer is challenging. Epidermal growth factor receptor (EGFR) contributes to the proliferation and development of gastric cancer (GC), and its overexpression is associated with unfavorable prognosis in GC. Cetuximab, a monoclonal antibody targeting EGFR, failed to improve the overall survival of gastric cancer patients indicated in phase III randomized trials. Glutamine is a vital nutrient for tumor growth and its metabolism contributes to therapeutic resistance, making glutamine uptake an attractive target for cancer treatment. The aim of the present study was to investigate whether intervention of glutamine uptake could improve the effect of cetuximab on GC. The results of MTT assay showed that by glutamine deprivation or inhibition of glutamine uptake, the viability of gastric carcinoma cells was inhibited more severely than that of human immortal gastric mucosa epithelial cells (GES-1). The expression of the key glutamine transporter alanine-serine-cysteine (ASC) transporter 2 (ASCT2; SLC1A5) was significantly higher in gastric carcinoma tissues and various gastric carcinoma cell lines than in normal gastric tissues and cells, as shown by immunohistochemistry and western blotting, while silencing ASCT2 significantly inhibited the viability and proliferation of gastric carcinoma cells. Consistent with previous studies, it was shown herein by MTT and EdU assays that cetuximab had a weak inhibitory effect on the cell viability of gastric carcinoma cells. However, inhibiting glutamine uptake by blockade of ASCT2 with l-γ-glutamyl-p-nitroanilide (GPNA) significantly enhanced the inhibitory effect of cetuximab on suppressing the proliferation of gastric cancer both in vitro and in vivo. Moreover, combining cetuximab and GPNA induced cell apoptosis considerably in gastric carcinoma cells, as shown by flow cytometry, and had a higher depressing effect on gastric cancer proliferation both in vitro and in vivo, as compared to either treatment alone. The present study suggested that inhibition of glutamine uptake may be a promising strategy for improving the inhibitory efficacy of cetuximab on advanced gastric cancer.


Assuntos
Glutamina , Neoplasias Gástricas , Sistema ASC de Transporte de Aminoácidos , Linhagem Celular Tumoral , Proliferação de Células , Cetuximab/farmacologia , Humanos , Antígenos de Histocompatibilidade Menor , Neoplasias Gástricas/tratamento farmacológico
4.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360933

RESUMO

Cisplatin is among the most widely used anticancer drugs used in the treatment of several malignancies, including oral cancer. However, cisplatin treatment often promotes chemical resistance, subsequently causing treatment failure. Several studies have shown that epidermal growth factor receptors (EGFRs) play a variety of roles in cancer progression and overcoming cisplatin resistance. Therefore, this study focused on EGFR inhibitors used in novel targeted therapies as a method to overcome this resistance. We herein aimed to determine whether the combined effects of cisplatin and cetuximab could enhance cisplatin sensitivity by inhibiting the epithelial-to-mesenchymal transition (EMT) process in cisplatin-resistant cells. In vitro analyses of three cisplatin-resistant oral squamous cell carcinoma cells, which included cell proliferation assay, combination index calculation, cell cytotoxicity assay, live/dead cell count assay, Western blot assay, propidium iodide staining assay, scratch assay, and qRT-PCR assay were then conducted. Our results showed that a cisplatin/cetuximab combination treatment inhibited cell proliferation, cell motility, and N-cadherin protein expression but induced E-cadherin and claudin-1 protein expression. Although the combination of cisplatin and cetuximab did not induce apoptosis of cisplatin-resistant cells, it may be useful in treating oral cancer patients with cisplatin resistance given that it controls cell motility and EMT-related proteins.


Assuntos
Cetuximab/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Combinação de Medicamentos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos
5.
Cancer Sci ; 112(9): 3856-3870, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34288281

RESUMO

Patients with BRAF-mutated colorectal cancer (CRC) have a poor prognosis despite recent therapeutic advances such as combination therapy with BRAF, MEK, and epidermal growth factor receptor (EGFR) inhibitors. To identify microRNAs (miRNAs) that can improve the efficacy of BRAF inhibitor dabrafenib (DAB) and MEK inhibitor trametinib (TRA), we screened 240 miRNAs in BRAF-mutated CRC cells and identified five candidate miRNAs. Overexpression of miR-193a-3p, one of the five screened miRNAs, in CRC cells inhibited cell proliferation by inducing apoptosis. Reverse-phase protein array analysis revealed that proteins with altered phosphorylation induced by miR-193a-3p were involved in several oncogenic pathways including MAPK-related pathways. Furthermore, overexpression of miR-193a-3p in BRAF-mutated cells enhanced the efficacy of DAB and TRA through inhibiting reactivation of MAPK signaling and inducing inhibition of Mcl1. Inhibition of Mcl1 by siRNA or by Mcl1 inhibitor increased the antiproliferative effect of combination therapy with DAB, TRA, and anti-EGFR antibody cetuximab. Collectively, our study demonstrated the possibility that miR-193a-3p acts as a tumor suppressor through regulating multiple proteins involved in oncogenesis and affects cellular sensitivity to MAPK-related pathway inhibitors such as BRAF inhibitors, MEK inhibitors, and/or anti-EGFR antibodies. Addition of miR-193a-3p and/or modulation of proteins involved in the miR-193a-3p-mediated pathway, such as Mcl1, to EGFR/BRAF/MEK inhibition may be a potential therapeutic strategy against BRAF-mutated CRC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/metabolismo , Genes Supressores de Tumor , Imidazóis/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Mutação , Oximas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/farmacologia , Pirimidinonas/farmacologia , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Cetuximab/farmacologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Quimioterapia Combinada/métodos , Receptores ErbB/antagonistas & inibidores , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transfecção
6.
Mol Med Rep ; 24(4)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34328195

RESUMO

Oral squamous cell carcinoma (OSCC) is a cancer associated with high mortality (accounting for 3.1/100,000 deaths per year in Brazil in 2013) and a high frequency of amplification in the expression of the epidermal growth factor receptor (EGFR). Treatment with the EGFR inhibitor cetuximab leads to drug resistance in patients with OSCC due to unknown mechanisms. Galectin­3 (Gal­3) is a ß­galactoside binding lectin that regulates multiple signaling pathways in cells. The present study aimed to investigate the effect of Gal­3 in cetuximab­resistant (cet­R) OSCC. The OSCC HSC3 cell line was selected to establish a mouse xenograft model, which was treated with cetuximab to induce resistance. Subsequently, a Gal­3 inhibitor was used to treat cet­R tumors, and the tumor volume was monitored. The expression of Gal­3, phosphorylated (p)­ERK1/2 and p­Akt was assessed using immunohistochemistry. The combined effect of cetuximab and the Gal­3 inhibitor on HSC3 tumor xenografts was also investigated. HSC3 cells were cultured in vitro to investigate the regulatory effects of Gal­3 on ERK1/2 and Akt via western blotting. In addition, the effects of the Gal­3 inhibitor on the proliferation, colony formation, invasion and apoptosis of HSC3 cells were investigated by performing Cell Counting Kit­8, colony formation, Transwell and apoptosis assays, respectively. In cet­R OSCC tumors, increased expression of Gal­3, p­ERK1/2 and p­Akt was observed. Further research demonstrated that Gal­3 regulated the expression of both ERK1/2 and Akt in HSC3 cells by promoting phosphorylation. Moreover, the Gal­3 inhibitor decreased the proliferation and invasion, but increased the apoptosis of cet­R HSC3 cells. In addition, the Gal­3 inhibitor suppressed the growth of cet­R tumors. Collectively, the results indicated that the Gal­3 inhibitor and cetuximab displayed a synergistic inhibitory effect on OSCC tumors. In summary, the present study demonstrated that Gal­3 may serve an important role in cet­R OSCC. The combination of cetuximab and the Gal­3 inhibitor may display a synergistic antitumor effect, thereby inhibiting the development of cetuximab resistance in OSCC.


Assuntos
Proteínas Sanguíneas/antagonistas & inibidores , Carcinoma de Células Escamosas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Galectinas/antagonistas & inibidores , Neoplasias Bucais/tratamento farmacológico , Animais , Antineoplásicos Imunológicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Sanguíneas/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cetuximab/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Galectinas/genética , Técnicas de Silenciamento de Genes , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Int J Mol Sci ; 22(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299137

RESUMO

The KRAS mutation is one of the leading driver mutations in colorectal cancer (CRC), and it is usually associated with poor prognosis and drug resistance. Therapies targeting the epidermal growth factor receptor (EFGR) are widely used for end-stage CRC. However, patients with KRAS mutant genes cannot benefit from this therapy because of Ras signaling activation by KRAS mutant genes. Our previous study revealed the anti-proliferative effect of 4-acetyl-antroquinonol B (4-AAQB) on CRC cells, but whether the drug is effective in KRAS-mutant CRC remains unknown. We screened CRC cell lines harboring the KRAS mutation, namely G12A, G12C, G12V and G13D, with one wild type cell line as the control; SW1463 and Caco-2 cell lines were used for further experiments. Sulforhodamine B assays, together with the clonogenicity and invasion assay, revealed that KRAS-mutant SW1463 cells were resistant to cetuximab; however, 4-AAQB treatment effectively resensitized CRC cells to cetuximab through the reduction of colony formation, invasion, and tumorsphere generation and of oncogenic KRAS signaling cascade of CRC cells. Thus, inducing cells with 4-AAQB before cetuximab therapy could resensitize KRAS-mutant, but not wild-type, cells to cetuximab. Therefore, we hypothesized that 4-AAQB can inhibit KRAS. In silico analysis of the publicly available GEO (GSE66548) dataset of KRAS-mutated versus KRAS wild-type CRC patients confirmed that miR-193a-3p was significantly downregulated in the former compared with the latter patient population. Overexpression of miR-193a-3p considerably reduced the oncogenicity of both CRC cells. Furthermore, KRAS is a key target of miR-193a-3p. In vivo treatment with the combination of 4-AAQB and cetuximab significantly reduced the tumor burden of a xenograft mice model through the reduction of the expression of oncogenic markers (EGFR) and p-MEK, p-ERK, and c-RAF/p-c-RAF signaling, with the simultaneous induction of miR-193a-3p expression in the plasma. In summary, our findings provide strong evidence regarding the therapeutic effect of 4-AAQB on KRAS-mutant CRC cells. Furthermore, 4-AAQB effectively inhibits Ras singling in CRC cells, through which KRAS-mutant CRC can be resensitized to cetuximab.


Assuntos
Biomarcadores Tumorais/metabolismo , Cetuximab/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Ubiquinona/análogos & derivados , Animais , Antineoplásicos Imunológicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Prognóstico , Células Tumorais Cultivadas , Ubiquinona/química , Ubiquinona/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases raf/genética , Quinases raf/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo
8.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281166

RESUMO

Cetuximab is a common treatment option for patients with wild-type K-Ras colorectal carcinoma. However, patients often display intrinsic resistance or acquire resistance to cetuximab following treatment. Here we generate two human CRC cells with acquired resistance to cetuximab that are derived from cetuximab-sensitive parental cell lines. These cetuximab-resistant cells display greater in vitro proliferation, colony formation and migration, and in vivo tumour growth compared with their parental counterparts. To evaluate potential alternative therapeutics to cetuximab-acquired-resistant cells, we tested the efficacy of 38 current FDA-approved agents against our cetuximab-acquired-resistant clones. We identified carfilzomib, a selective proteosome inhibitor to be most effective against our cell lines. Carfilzomib displayed potent antiproliferative effects, induced the unfolded protein response as determined by enhanced CHOP expression and ATF6 activity, and enhanced apoptosis as determined by enhanced caspase-3/7 activity. Overall, our results indicate a potentially novel indication for carfilzomib: that of a potential alternative agent to treat cetuximab-resistant colorectal cancer.


Assuntos
Neoplasias Colorretais/metabolismo , Oligopeptídeos/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cetuximab/farmacologia , Neoplasias Colorretais/fisiopatologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Oligopeptídeos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Resposta a Proteínas não Dobradas/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Anticancer Res ; 41(7): 3363-3370, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230132

RESUMO

BACKGROUND/AIM: The mechanisms through which cetuximab (cMab) coadministration with paclitaxel (PTX) enhances antitumor efficacy remain unclear. We examined the mechanism of the antitumor enhancing effect of cMab by determining changes in gene expression in the PI3K-AKT pathway. MATERIALS AND METHODS: Eight human oral squamous cell carcinoma (OSCC) cell lines were cultured three-dimensionally and exposed to PTX + cMab. The expression levels of PTEN mRNA in OSCC cell lines after anticancer drug treatment were assessed using real-time PCR. PTEN mRNA expression levels were also confirmed after administration of PTX + cMab in vivo. Western blot analysis was used to confirm the results at the protein level. RESULTS: PTEN mRNA and protein expression were significantly increased only in the cell lines with high sensitivity to PTX + cMab, and similar results were observed in vivo. CONCLUSION: PTEN activation may enhance the antitumor effect of PTX + cMab.


Assuntos
Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , PTEN Fosfo-Hidrolase/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Cetuximab/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Paclitaxel/farmacologia , Fosfatidilinositol 3-Quinases/genética
10.
Magy Onkol ; 65(2): 188-195, 2021 06 03.
Artigo em Húngaro | MEDLINE | ID: mdl-34081766

RESUMO

Head and neck squamous cell carcinomas (HNSCC) take many lifes worldwide. Patients with recurrent/metastatic disease receive combination chemotherapy containing anti-EGFR antibody cetuximab. However, resistance often hurdles therapy. The mechanism is yet to unveil, although EGFR extracellular alterations and activity of c-Met signaling were accused. We investigated the effects of EGFR-vIII and EGFR-R521K on cetuximab efficacy in HNSCC in cellular, xenograft, and clinical setup. Furthermore, we investigated the efficacy of c-Met inhibition in HNSCC in vitro and in vivo. We showed that EGFR-vIII is very rare in HNSCC, while the common R521K polymorphism abolishes antibody-dependent cellular cytotoxicity and in vivo antitumor effect of cetuximab. This selectivity was not reflected in immunophenotype or survival data of HNSCC patients, suggesting a more complex mechanism behind. Interestingly, c-Met inhibitor SU11274 was more effective in cetuximab-resistant, EGFR R521K heterozygous cells and xenografts, raising the possible importance of simultaneous targeting of the two receptors.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Cetuximab/farmacologia , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/genética , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071597

RESUMO

In the search of new natural products to be explored as possible anticancer drugs, two plant species, namely Ononis diffusa and Ononis variegata, were screened against colorectal cancer cell lines. The cytotoxic activity of the crude extracts was tested on a panel of colon cancer cell models including cetuximab-sensitive (Caco-2, GEO, SW48), intrinsic (HT-29 and HCT-116), and acquired (GEO-CR, SW48-CR) cetuximab-resistant cell lines. Ononis diffusa showed remarkable cytotoxic activity, especially on the cetuximab-resistant cell lines. The active extract composition was determined by NMR analysis. Given its complexity, a partial purification was then carried out. The fractions obtained were again tested for their biological activity and their metabolite content was determined by 1D and 2D NMR analysis. The study led to the identification of a fraction enriched in oxylipins that showed a 92% growth inhibition of the HT-29 cell line at a concentration of 50 µg/mL.


Assuntos
Cetuximab/farmacologia , Neoplasias do Colo/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Espectroscopia de Ressonância Magnética/métodos , Ononis/metabolismo , Extratos Vegetais/farmacologia , Células CACO-2 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Desenho de Fármacos , Células HCT116 , Células HT29 , Humanos , Oxilipinas/química , Fitoterapia/métodos , Especificidade da Espécie
12.
Cancer Sci ; 112(8): 3029-3040, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34058788

RESUMO

Integrin associated protein (CD47) is an important target in immunotherapy, as it is expressed as a "don't eat me" signal on many tumor cells. Interference with its counter molecule signal regulatory protein alpha (SIRPα), expressed on myeloid cells, can be achieved with blocking Abs, but also by inhibiting the enzyme glutaminyl cyclase (QC) with small molecules. Glutaminyl cyclase inhibition reduces N-terminal pyro-glutamate formation of CD47 at the SIRPα binding site. Here, we investigated the impact of QC inhibition on myeloid effector cell-mediated tumor cell killing by epidermal growth factor receptor (EGFR) Abs and the influence of Ab isotypes. SEN177 is a QC inhibitor and did not interfere with EGFR Ab-mediated direct growth inhibition, complement-dependent cytotoxicity, or Ab-dependent cell-mediated cytotoxicity (ADCC) by mononuclear cells. However, binding of a human soluble SIRPα-Fc fusion protein to SEN177 treated cancer cells was significantly reduced in a dose-dependent manner, suggesting that pyro-glutamate formation of CD47 was affected. Glutaminyl cyclase inhibition in tumor cells translated into enhanced Ab-dependent cellular phagocytosis by macrophages and enhanced ADCC by polymorphonuclear neutrophilic granulocytes. Polymorphonuclear neutrophilic granulocyte-mediated ADCC was significantly more effective with EGFR Abs of human IgG2 or IgA2 isotypes than with IgG1 Abs, proposing that the selection of Ab isotypes could critically affect the efficacy of Ab therapy in the presence of QC inhibition. Importantly, QC inhibition also enhanced the therapeutic efficacy of EGFR Abs in vivo. Together, these results suggest a novel approach to specifically enhance myeloid effector cell-mediated efficacy of EGFR Abs by orally applicable small molecule QC inhibitors.


Assuntos
Aminoaciltransferases/antagonistas & inibidores , Antígenos de Diferenciação/química , Antineoplásicos Imunológicos/administração & dosagem , Antígeno CD47/metabolismo , Neoplasias/tratamento farmacológico , Receptores Imunológicos/química , Bibliotecas de Moléculas Pequenas/administração & dosagem , Animais , Antígenos de Diferenciação/metabolismo , Antineoplásicos Imunológicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cetuximab/administração & dosagem , Cetuximab/farmacologia , Sinergismo Farmacológico , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Neoplasias/metabolismo , Panitumumabe/administração & dosagem , Panitumumabe/farmacologia , Ligação Proteica/efeitos dos fármacos , Receptores Imunológicos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Head Neck ; 43(9): 2712-2723, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34033197

RESUMO

BACKGROUND: Cetuximab has been widely used in the clinical treatment of head and neck squamous cell carcinoma (HNSCC). However, whether long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) is correlated with cetuximab resistance remains unclear. METHODS: Western blot and qRT-PCR were performed to quantify the levels of genes and proteins, respectively. Cell functions were measured using Cell Counting Kit-8 (CCK-8), Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and flow cytometry assays. The methylation level was tested using methylation-specific PCR (MSP). RESULTS: PVT1 was upregulated and positively correlated with the poor prognosis of HNSCC. PVT1 overexpression markedly promoted the survival and weakened the cetuximab sensitivity of HNSCC cells, while miR-124-3p overexpression showed opposite effects. Mechanistically, the silence of PVT1 indirectly promoted miR-124-3p expression by reducing its promoter methylation. Importantly, miR-124-3p overexpression impeded the regulatory roles of PVT1 overexpression. CONCLUSION: PVT1 decreased the sensitivity of HNSCC cells to cetuximab by enhancing methylation-mediated inhibition of miR-124-3p, which might provide a new insight for the cetuximab chemoresistance of HNSCC.


Assuntos
Cetuximab , Neoplasias de Cabeça e Pescoço , MicroRNAs , RNA Longo não Codificante , Carcinoma de Células Escamosas de Cabeça e Pescoço , Linhagem Celular Tumoral , Proliferação de Células , Cetuximab/farmacologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
14.
Mar Drugs ; 19(5)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946151

RESUMO

Sulfated galactans (SG) isolated from red alga Gracilaria fisheri have been reported to inhibit the growth of cholangiocarcinoma (CCA) cells, which was similar to the epidermal growth factor receptor (EGFR)-targeted drug, cetuximab. Herein, we studied the anti-cancer potency of SG compared to cetuximab. Biological studies demonstrated SG and cetuximab had similar inhibition mechanisms in CCA cells by down-regulating EGFR/ERK pathway, and the combined treatment induced a greater inhibition effect. The molecular docking study revealed that SG binds to the dimerization domain of EGFR, and this was confirmed by dimerization assay, which showed that SG inhibited ligand-induced EGFR dimer formation. Synchrotron FTIR microspectroscopy was employed to examine alterations in cellular macromolecules after drug treatment. The SR-FTIR-MS elicited similar spectral signatures of SG and cetuximab, pointing towards the bands of RNA/DNA, lipids, and amide I vibrations, which were inconsistent with the changes of signaling proteins in CCA cells after drug treatment. Thus, this study demonstrates the underlined anti-cancer mechanism of SG by interfering with EGFR dimerization. In addition, we reveal that FTIR signature spectra offer a useful tool for screening anti-cancer drugs' effect.


Assuntos
Antineoplásicos/farmacologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Galactanos/farmacologia , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Enxofre/farmacologia , Antineoplásicos/metabolismo , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cetuximab/farmacologia , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Galactanos/metabolismo , Humanos , Microespectrofotometria , Ligação Proteica , Multimerização Proteica , Transdução de Sinais , Compostos de Enxofre/metabolismo , Síncrotrons
15.
J Transl Med ; 19(1): 185, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933132

RESUMO

BACKGROUND: Cetuximab has been approved for use for first-line treatment of patients with wild-type KRAS metastatic colorectal cancer (CRC). However, treatment with cetuximab has shown limited efficacy as a CRC monotherapy. In addition, natural killer (NK) cell function is known to be severely attenuated in cancer patients. The goal of this study was to develop a new strategy to enhance antibody-dependent cell-mediated cytotoxicity (ADCC) mediated by NK cells, in combination with cetuximab against CRC cells. METHODS: Ex vivo expanded NK cells were stimulated with reovirus, and reovirus-activated NK cells mediated ADCC assay were performed on CRC cells in combination with cetuximab. The synergistic antitumor effects of reovirus-activated NK cells and cetuximab were tested on DLD-1 tumor-bearing mice. Finally, Toll-like receptor 3 (TLR3) knockdown in NK cells, along with chemical blockade of TLR3/dsRNA complex, and inhibition of the TLR3 downstream signaling pathway, were performed to explore the mechanisms by which reovirus enhances NK cell cytotoxicity. RESULTS: We first confirmed that exposure of NK cells to reovirus enhanced their cytotoxicity in a dose-dependent manner.We then investigated whether reovirus-activated NK cells exposed to cetuximab-bound CRC cells exhibited greater anti-tumor efficacy than either monotherapy. Co-culture of CRC cell lines with reovirus-activated NK cells indicated that NK cytotoxicity was significantly higher in combination with cetuximab, regardless of KRAS mutation status or EGFR expression level. We also found that reovirus activation of NK cells, in conjunction with cetuximab, resulted in significantly stronger anti-tumor efficacy.Finally, TLR3 knockdown, inhibition of TLR3/dsRNA complex or TBK1/IKKε demonstrated that activation of NK cells by reovirus was dependent on TLR3 and its downstream signaling pathway. CONCLUSIONS: This study demonstrated that combination treatment of reovirus-activated NK cells with cetuximab synergistically enhances their anti-tumor cytotoxicity, suggesting a strong candidate strategy for clinical treatment of CRC.


Assuntos
Neoplasias Colorretais , Receptor 3 Toll-Like , Animais , Citotoxicidade Celular Dependente de Anticorpos , Linhagem Celular Tumoral , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Humanos , Células Matadoras Naturais , Camundongos
16.
ACS Chem Biol ; 16(4): 724-730, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33829754

RESUMO

While Cetuximab can be used to treat KRAS wild-type colon cancer cells by targeting EGFR and inhibiting the activation of downstream signaling pathways, it exhibits little therapeutic effect on KRAS mutant colon cancer cells. Natural killer (NK) cells are a class of powerful immune cells with anticancer activities. However, NK cells typically lack inherent tumor targeting abilities. Here, a new method is established to bestow NK-92 cells with tumor targeting abilities by installing cetuximab on the cell surface. Through metabolic glycoengineering, azide groups were introduced onto the surface of NK-92 cells. Bioorthogonal strain promoted the azide-alkyne cycloaddition click reaction of engineered NK-92 cells with alkyne modified cetuximab functionalized NK cells with the antibody. The resulting NK-92 cells were significantly more effective than the parent NK-92 cells in protecting against tumor development in a KRAS mutant mouse tumor model resistant to cetuximab treatment. Thus, NK cell functionalization with antibodies enabled by metabolic glycoengineering is a promising strategy to enhance anticancer immune therapy.


Assuntos
Cetuximab/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Genes ras , Células Matadoras Naturais/imunologia , Mutação , Anticorpos Monoclonais Humanizados/imunologia , Cetuximab/uso terapêutico , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Receptores ErbB/genética , Receptores ErbB/imunologia , Feminino , Humanos
17.
Nat Commun ; 12(1): 2335, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879799

RESUMO

Current therapeutic options for treating colorectal cancer have little clinical efficacy and acquired resistance during treatment is common, even following patient stratification. Understanding the mechanisms that promote therapy resistance may lead to the development of novel therapeutic options that complement existing treatments and improve patient outcome. Here, we identify RAC1B as an important mediator of colorectal tumourigenesis and a potential target for enhancing the efficacy of EGFR inhibitor treatment. We find that high RAC1B expression in human colorectal cancer is associated with aggressive disease and poor prognosis and deletion of Rac1b in a mouse colorectal cancer model reduces tumourigenesis. We demonstrate that RAC1B interacts with, and is required for efficient activation of the EGFR signalling pathway. Moreover, RAC1B inhibition sensitises cetuximab resistant human tumour organoids to the effects of EGFR inhibition, outlining a potential therapeutic target for improving the clinical efficacy of EGFR inhibitors in colorectal cancer.


Assuntos
Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Antineoplásicos Imunológicos/farmacologia , Carcinogênese , Linhagem Celular Tumoral , Cetuximab/farmacologia , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeos/deficiência , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Transdução de Sinais , Regulação para Cima , Via de Sinalização Wnt , Proteínas rac1 de Ligação ao GTP/deficiência , Proteínas rac1 de Ligação ao GTP/genética
18.
Cancer Invest ; 39(4): 285-296, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33646061

RESUMO

The switchable chimeric antigen receptors (CARs) have shown many advantages in CAR T-cell therapy. However, human primary T-cells are required to evaluate antigen-specific adaptors by IFN-γ assay or FACS analysis, which limits the throughput of adaptor screening. A sensitive and robust CD16-CAR Jurkat NFAT-eGFP reporter system has been developed to assess the therapeutic efficacy of antibody-targeted CAR-T-cell by effectively evaluating the T-cell activation by various tumor cells and the impact of immune checkpoint inhibitor antibodies. This reporter system facilitates the screening of targeted antibodies in a high throughput manner for the development of improved T-cell immunotherapy.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos Imunológicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Cetuximab/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia Adotiva , Neoplasias/terapia , Receptores de Antígenos Quiméricos/imunologia , Receptores de IgG/imunologia , Linfócitos T/transplante , Células A549 , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Células HCT116 , Ensaios de Triagem em Larga Escala , Humanos , Células Jurkat , Fatores de Transcrição NFATC/genética , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Receptores de IgG/genética , Receptores de IgG/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo
19.
Biomater Sci ; 9(6): 2279-2294, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33538278

RESUMO

Antibody-functionalized targeted nanocarriers to deliver chemotherapeutics have been widely explored. However, it remains highly desirable to understand and apply the antitumor potential of antibodies integrated in hybrid composite nanoplatforms. Herein, mesoporous silica nanoparticles, a supported lipid bilayer and cetuximab were integrated to fabricate a hybrid nanoplatform for effectively encapsulating and selectively delivering 5-fluorouracil (5-FU) against colorectal cancer (CRC) cells. The specially designed nanoplatform exhibited superior properties, such as satisfying size distribution, dispersity and stability, drug encapsulation, controlled release, and cellular uptake. Interestingly, the modification of cetuximab onto nanoplatforms without drug loading can significantly inhibit the migration and invasion of CRC cells through suppressing the epidermal growth factor receptor (EGFR)-associated signaling pathway. Furthermore, delivery of 5-FU by using this nanoplatform can remarkably induce cytotoxicity, cell cycle arrest, and cell apoptosis for CRC cells with high EGFR expression. Overall, this nanostructured platform can dramatically improve the tumor killing effects of encapsulated chemotherapeutics and present antimigration effects derived from the antibody modified on it. Moreover, in vivo biodistribution experiments demonstrated the superior tumor targeting ability of the targeted nanoparticles. Thus, this targeted nanoplatform has substantial potential in combinational therapy of antibodies and chemotherapy agents against colorectal cancer.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Nanopartículas , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cetuximab/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/farmacologia , Humanos , Distribuição Tecidual
20.
J Clin Invest ; 131(6)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33561014

RESUMO

Most clinically used anticancer mAbs are of the IgG isotype, which can eliminate tumor cells through NK cell-mediated antibody-dependent cellular cytotoxicity and macrophage-mediated antibody-dependent phagocytosis. IgG, however, ineffectively recruits neutrophils as effector cells. IgA mAbs induce migration and activation of neutrophils through the IgA Fc receptor (FcαRI) but are unable to activate NK cells and have poorer half-life. Here, we combined the agonistic activity of IgG mAbs and FcαRI targeting in a therapeutic bispecific antibody format. The resulting TrisomAb molecules recruited NK cells, macrophages, and neutrophils as effector cells for eradication of tumor cells in vitro and in vivo. Moreover, TrisomAb had long in vivo half-life and strongly decreased B16F10gp75 tumor outgrowth in mice. Importantly, neutrophils of colorectal cancer patients effectively eliminated tumor cells in the presence of anti-EGFR TrisomAb but were less efficient in mediating killing in the presence of IgG anti-EGFR mAb (cetuximab). The clinical application of TrisomAb may provide potential alternatives for cancer patients who do not benefit from current IgG mAb therapy.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antineoplásicos Imunológicos/farmacologia , Neutrófilos/imunologia , Animais , Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Linhagem Celular Tumoral , Cetuximab/farmacologia , Feminino , Células HCT116 , Humanos , Imunoglobulina G/imunologia , Células Matadoras Naturais/imunologia , Macrófagos/imunologia , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Imunológicos , Receptores Fc/imunologia
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