RESUMO
Small extracellular vesicles (sEVs) are reliable biomarkers for early cancer detection; however, conventional detection methods such as immune-based assays and microRNA analyses are not very sensitive and require sample pretreatments and long analysis time. Here, we developed a molecular imprinting-based dynamic molding approach to fabricate antibody-conjugated signaling nanocavities capable of size recognition. This enabled the establishment of an easy-to-use, rapid, sensitive, pretreatment-free, and noninvasive sEV detection platform for efficient sEV detection-based cancer diagnosis. An apparent dissociation constant was estimated to be 2.4 × 10-16 M, which was â¼1000 times higher than that of commercial immunoassays (analysis time, 5 min/sample). We successfully used tears for the first time to detect cancer-related intact sEVs, clearly differentiating between healthy donors and breast cancer patients, as well as between samples collected before and after total mastectomy. Our nanoprocessing strategy can be easily repurposed for the specific detection of other types of cancer by changing the conjugated antibodies, thereby facilitating the establishment of liquid biopsy for early cancer diagnosis.
Assuntos
Anticorpos/química , Vesículas Extracelulares/química , Nanotecnologia/métodos , Lágrimas/química , Humanos , Transdução de SinaisRESUMO
Methionine addiction is a fundamental and general hallmark of cancer. Methionine addiction prevents cancer cells, but not normal cells from proliferation under methionine restriction (MR). Previous studies reported that MR altered the histone methylation levels in methionine-addicted cancer cells. However, no study has yet compared the status of histone methylation status, under MR, between cancer cells and normal cells. In the present study, we compared the histone methylation status between cancer cells and normal fibroblasts of H3K4me3 and H3K9me3, using recombinant methioninase (rMETase) to effect MR. Human lung and colon cancer cell lines and human normal foreskin fibroblasts were cultured in control medium or medium with rMETase. The viability of foreskin fibroblasts was approximately 10 times more resistant to rMETase than the cancer cells in vitro. Proliferation only of the cancer cells ceased under MR. The histone methylation status of H3K4me3 and H3K9me3 under MR was evaluated by immunoblotting. The levels of the H3K4me3 and H3K9me3 were strongly decreased by MR in the cancer cells. In contrast, the levels of H3K4me3 and H3K9me3 were not altered by MR in normal fibroblasts. The present results suggest that histone methylation status of H3K4me3 and H3K9me3 under MR was unstable in cancer cells but stable in normal cells and the instability of histone methylation status under MR may determine the high methionine dependency of cancer cells to survive and proliferate.
Assuntos
Neoplasias do Colo/metabolismo , Fibroblastos/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Metionina/deficiência , Metionina/metabolismo , Liases de Carbono-Enxofre/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Neoplasias do Colo/enzimologia , Humanos , Neoplasias Pulmonares/enzimologia , Metilação , Proteínas RecombinantesRESUMO
Exosomes are small (30-100â nm) membrane vesicles that serve as regulatory agents for intercellular communication in cancers. Currently, exosomes are detected by immuno-based assays with appropriate pretreatments like ultracentrifugation and are time consuming (>12â h). We present a novel pretreatment-free fluorescence-based sensing platform for intact exosomes, wherein exchangeable antibodies and fluorescent reporter molecules were aligned inside exosome-binding cavities. Such antibody-containing fluorescent reporter-grafted nanocavities were prepared on a substrate by well-designed molecular imprinting and post-imprinting modifications to introduce antibodies and fluorescent reporter molecules only inside the binding nanocavities, enabling sufficiently high sensitivity to detect intact exosomes without pretreatment. The effectiveness of the system was demonstrated by using it to discriminate between normal exosomes and those originating from prostate cancer and analyze exosomes in tear drops.
Assuntos
Exossomos/metabolismo , Impressão Molecular , Polímeros/metabolismo , Neoplasias da Próstata/diagnóstico por imagem , Exossomos/química , Fluorescência , Humanos , Masculino , Estrutura Molecular , Células PC-3 , Polímeros/química , Neoplasias da Próstata/metabolismo , Processamento de Proteína Pós-Traducional , UltracentrifugaçãoRESUMO
BACKGROUND/AIM: BRCA1/2 mutations in breast cancer cells impair homologous recombination and promote alternative end joining (Alt-EJ) for DNA-damage repair. DNA polymerase theta, encoded by POLQ, plays a crucial role in Alt-EJ, making it a potential therapeutic target, particularly in BRCA1/2-mutant cancers. Methionine restriction is a promising approach to target cancer cells due to their addiction to this amino acid. The present study investigated the expression of POLQ in BRCA1/2 wild-type and BRCA1-mutant breast cancer cells under methionine restriction. MATERIALS AND METHODS: POLQ mRNA expression was measured using qRT-PCR in BRCA1/2 wild-type (MDA-MB-231) and BRCA1- mutant (HCC1937 and MDA-MB-436) breast-cancer cells under normal, or serum-restricted, or serum- and methionine-restricted conditions. RESULTS: Compared to BRCA1/2 wild-type cells, BRCA1-mutant cells displayed significantly higher basal POLQ expression in normal medium. Methionine restriction further increased POLQ expression in the BRCA1-mutant cells but decreased it in the BRCA1/2 wild-type cells. CONCLUSION: The present findings suggest that methionine restriction showed differential effects on POLQ expression, potentially impacting Alt-EJ activity, in BRCA1/2 wild-type and BRCA1-mutant breast-cancer cells. Further investigation is needed to explore the potential of combining methionine restriction with DNA-repair inhibitors, such as PARP inhibitors, to overcome drug resistance in BRCA1/2 mutant cancers.
Assuntos
Proteína BRCA1 , Neoplasias da Mama , DNA Polimerase teta , Metionina , Mutação , Humanos , Metionina/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , Reparo do DNA , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteína BRCA2/genética , Proteína BRCA2/metabolismoRESUMO
BACKGROUND/AIM: Methionine addiction is the elevated requirement for exogenous methionine for growth and survival of cancer cells, termed the Hoffman effect. Methionine-addicted cancer cells synthesize normal or excess amounts of methionine but still need an external source of methionine. Methionine restriction (MR) by either a methionine-free medium or in vivo by a low-methionine diet or by methioninase, selectively arrests cancer cells in the late S/G2 cell cycle phase, but not normal cells. The present study focuses on the comparison of production and secretion of exosomes by cancer cells under MR and normal conditions. MATERIALS AND METHODS: MDA-MB-231 cells (triple-negative breast cancer), containing exosomes labeled with CD63-GFP (CD63-GFP exosomes), were visualized by fluorescence microscopy. MDA-MB-231 cells expressing exosome-specific CD63-GFP were cultured in methionine-containing (MET+) or in methionine-free (MET-) DMEM conditions. Exosomes were isolated from conditioned medium of cultured MDA-MD-231 cells by ultracentrifugation and characterized by nanoparticle tracking analysis (NTA) and Western blotting. RESULTS: When MDA-MB-231-CD63-GFP cells were cultured under MR conditions, they arrested their growth and CD63-GFP-expressing exosomes were strongly increased in the cells. MR resulted in approximately a 2-fold increase in exosome production and secretion per cell, even though cell growth was arrested. Methionine restriction thus resulted in elevated exosome production and secretion per surviving cell. CONCLUSION: Exosome production and secretion in the cancer cells increased under MR, suggesting a relation between MR and exosome production and secretion.
Assuntos
Neoplasias da Mama , Exossomos , Humanos , Feminino , Metionina/metabolismo , Exossomos/metabolismo , Neoplasias da Mama/metabolismo , Proliferação de Células , Racemetionina/metabolismoRESUMO
BACKGROUND/AIM: Breast cancer that is estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and human epidermal growth factor receptor-2 (HER2)-negative is termed triple-negative breast cancer (TNBC). Cytotoxic chemotherapy remains the first choice of treatment against TNBC due to lack of specific therapeutic targets. TNBC is not classified based on therapeutic targets, but recently, the development of targeted therapies - including immune checkpoint inhibitors and poly (adenosine diphosphate-ribose) polymerase inhibitors - has gained attention. This study aimed to examine a novel target-oriented TNBC classification to further facilitate targeted therapy by classifying TNBC based on the breast cancer 1 (BRCA1)-like as well as the protein expression of HER2, programmed death ligand 1 (PD-L1), androgen receptor (AR), cytokeratin 5/6, and epidermal growth factor receptor (EGFR). PATIENTS AND METHODS: We enrolled 17 patients with primary TNBC who did not receive preoperative chemotherapy and underwent surgery at the Kobe University Hospital, Japan, between January 1, 2018, and July 31, 2019. Immunohistochemical staining was performed on tumor specimens, while a BRCAness test was performed using multiplex ligation-dependent probe amplification (MLPA) analysis. A BRCAness score 0.5 or higher was considered BRCA1-like. RESULTS: Tumors were classified as HER2-low (immunohistochemistry score 1+ or 2+ and FISH negative), PD-L1 positive, AR positive, or BRCA1-like. HER2-low, PD-L1 positive, AR positive, and BRCA1-like were detected in 11 (64.7%), 4 (23.5%), 6 (35.3%), and 6 (35.3%) samples. The tumor of only one patient could not be classified into any of these categories. CONCLUSION: Almost all TNBC cases can be classified according to treatable targets.
Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/genética , Antígeno B7-H1/genética , Hospitais Universitários , Inibidores de Checkpoint Imunológico , Japão , Pentosiltransferases , Poli(ADP-Ribose) PolimerasesRESUMO
The high incidence and mortality of cancer make it a global health issue. However, conventional cancer therapies have several disadvantages, especially serious side effects due to low selective toxicity to cancer cells. Gold nanoparticles (AuNPs) are an excellent drug carrier, enhance drug delivery efficiency, and hold promise for photothermal and radiation therapies. (-)-Epigallocatechin-3-gallate (EGCG) is the major polyphenolic antioxidant constituent of green tea, has a potent antitumor effect, and binds specifically to the 67 kDa laminin receptor, which is overexpressed on the surface of several cancer cell lines such as HeLa and MDA-MB-231 cells. We synthesized EGCG-modified AuNPs (EGCG-AuNPs) using ratios (nEGCG/ngold) from 1:2 to 10:1 and evaluated their size, morphology, stability, antioxidant ability, cytotoxicity, cellular uptake, and uptake mechanisms in vitro in comparison with the conventional AuNPs prepared by using citrate as the reducing agent (citrate-AuNPs). In HeLa cells, EGCG-AuNPs (10:1) (135 nm diameter, sea-urchin-like shape) exhibited the highest cellular uptake. Conversely, EGCG-AuNPs (1:2) (39 nm diameter, spherical shape) were preferentially taken up by MDA-MB-231 cells. Cellular uptake of EGCG-AuNPs toward normal cells (NIH3T3 cells) was found to be in a nonspecific manner, and the amount of uptake was suppressed. X-ray irradiation after cellular uptake of EGCG-AuNPs (1:2) in MDA-MB-231 cells significantly enhanced irradiation-induced cell death. These findings suggest enhanced cellular uptake of EGCG-AuNPs with a 39 nm diameter and their potential use in combinatorial therapeutics of EGCG-AuNPs for breast cancer.
Assuntos
Ouro , Nanopartículas Metálicas , Animais , Antioxidantes/farmacologia , Catequina/análogos & derivados , Ácido Cítrico , Ouro/farmacologia , Células HeLa , Humanos , Camundongos , Células NIH 3T3RESUMO
A 56-year-old female patient with left breast cancer presented at our hospital. Preoperative CT scan showed an isolated bilateral pectoralis major muscle defect and abnormal muscle originating from the entire sternum and inserting in the lower ribs and rectus sheath. Total mastectomy and axillary lymph node dissection were performed. We believe that this case is unique and that others like it have never been reported. If there is a defect in the pectoralis major muscle, reconstructive surgery with a tissue expander is contraindicated. Therefore, preoperative evaluation of the chest wall musculature on imaging is recommended.
RESUMO
Methionine addiction, a fundamental and general hallmark of cancer, known as the Hoffman Effect, is due to altered use of methionine for increased and aberrant transmethylation reactions. However, the linkage of methionine addiction and malignancy of cancer cells is incompletely understood. An isogenic pair of methionine-addicted parental osteosarcoma cells and their rare methionine-independent revertant cells enabled us to compare them for malignancy, their epithelial-mesenchymal phenotype, and pattern of histone-H3 lysine-methylation. Methionine-independent revertant 143B osteosarcoma cells (143B-R) were selected from methionine-addicted parental cells (143B-P) by their chronic growth in low-methionine culture medium for 4 passages, which was depleted of methionine by recombinant methioninase (rMETase). Cell-migration capacity was compared with a wound-healing assay and invasion capability was compared with a transwell assay in 143B-P and 143B-R cells in vitro. Tumor growth and metastatic potential were compared after orthotopic cell-injection into the tibia bone of nude mice in vivo. Epithelial-mesenchymal phenotypic expression and the status of H3 lysine-methylation were determined with western immunoblotting. 143B-P cells had an IC50 of 0.20 U/ml and 143B-R cells had an IC50 of 0.68 U/ml for treatment with rMETase, demonstrating that 143B-R cells had regained the ability to grow in low methionine conditions. 143B-R cells had reduced cell migration and invasion capability in vitro, formed much smaller tumors than 143B-P cells and lost metastatic potential in vivo, indicating loss of malignancy in 143B-R cells. 143B-R cells showed gain of the epithelial marker, ZO-1 and loss of mesenchymal markers, vimentin, Snail, and Slug and, an increase of histone H3K9me3 and H3K27me3 methylation and a decrease of H3K4me3, H3K36me3, and H3K79me3 methylation, along with their loss of malignancy. These results suggest that shifting the balance in histone methylases might be a way to decrease the malignant potential of cells. The present results demonstrate the rationale to target methionine addiction for improved sarcoma therapy.
RESUMO
BACKGROUND/AIM: Methionine addiction is a fundamental and general hallmark of cancer, termed the Hoffman effect. Methionine addiction is due to excessive use of and dependence on methionine by cancer cells. In the present report, we correlated the extent of methionine addiction and degree of malignancy with the amount and stability of methylated histone H3 lysine marks. MATERIALS AND METHODS: We established low- and high-malignancy variants from a parental human pancreatic-cancer cell line and compared their sensitivity to methionine restriction and histone H3 lysine methylation status. RESULTS: A low-malignancy, low-methionine-addiction revertant of the parental pancreatic-cancer cell line had less methylated H3K9me3 and was less sensitive to methionine restriction effected by recombinant methioninase (rMETase) than the parental cell line. A high-malignancy variant of the pancreatic cancer cell line had increased methylated H3K9me3 and was more sensitive to methionine restriction by rMETase with regard to inhibition of proliferation and to instability of histone H3 lysine methylation than the parental cell line. Orthotopic malignancy in nude mice was reduced in the low-methionine-addiction revertant and greater in the high-malignancy variant than in the parental cell line. CONCLUSION: The present study indicates that the degree of malignancy is linked to the extent of methionine addiction and the level and instability of trimethylation of histone H3, suggesting these phenomena are linked as a fundamental basis of oncogenic transformation.
Assuntos
Transformação Celular Neoplásica/genética , Histonas/metabolismo , Metionina/metabolismo , Neoplasias Pancreáticas/genética , Animais , Liases de Carbono-Enxofre/farmacologia , Liases de Carbono-Enxofre/uso terapêutico , Linhagem Celular Tumoral , Transformação Celular Neoplásica/efeitos dos fármacos , Código das Histonas/efeitos dos fármacos , Humanos , Lisina/metabolismo , Metilação/efeitos dos fármacos , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Carga Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Methionine addiction, found in all types of cancer investigated, is because of the overuse of methionine by cancer cells for excess transmethylation reactions. In the present study, we compared the histone H3 lysine-methylation status and degree of malignancy between methionine-addicted cancer cells and their isogenic methionine-independent revertants, selected by their growth in low concentration of methionine. The methionine-independent revertans can grow on low levels of methionine or independently of exogenous methionine using methionine precursors, as do normal cells. In the methionine-independent revertants, the excess levels of trimethylated histone H3 lysine marks found in the methionine-addicted parental cancer cells were reduced or lost, and their tumorigenicity and experimental metastatic potential in nude mice were also highly reduced. Methionine addiction of cancer is linked with malignancy and hypermethylation of histone H3 lysines. The results of the present study thus provide a unique framework to further understand a fundamental basis of malignancy.
RESUMO
BACKGROUND/AIM: Sarcomas are considered a heterogeneous disease with incomplete understanding of its molecular basis. In the present study, to further understand general molecular changes in sarcoma, patient-derived xenograft (PDX) mouse models of the three most common soft-tissue sarcomas: myxofibrosarcoma, undifferentiated pleomorphic sarcoma (UPS) and liposarcoma were established and the methylation status of histone H3 lysine marks was studied. MATERIALS AND METHODS: Immunoblotting and immunohistochemical staining were used to quantify the extent of methylation of histone H3K4me3 and histone H3K9me3. RESULTS: In all 3 sarcoma types in PDX models, histone H3K4me3 and H3K9me3 were found highly over-methylated compared to normal muscle tissue. CONCLUSION: Histone H3 lysine over-methylation may be a general basis of malignancy of the major sarcoma types.
Assuntos
Histonas/metabolismo , Sarcoma/genética , Idoso , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Metilação , Camundongos , Camundongos Nus , Sarcoma/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND/AIM: Methionine addiction, a fundamental and general hallmark of cancer, is due to the excess use of methionine for transmethylation, and is described as the Hoffman-effect. Methionine-addicted cancer cells can revert at low frequency to methionine independence when selected under methionine-restriction. We report here that highly-malignant methionine-addicted H460 human lung-cancer cells, when selected for methionine independence, have greatly-reduced tumorigenic potential. MATERIALS AND METHODS: Methionine-addicted H460 parental cancer cells and methionine-independent revertant H460-R1 cells were injected in nude mice subcutaneously. RESULTS: When the parental H460 methionine-addicted cells were injected in nude mice at 2.5×105, 1×105 and 5×104, the cells could form tumors. In contrast, the H460-R1 methionine-independent revertant cells could not form tumors when the above-listed cell numbers were injected in nude mice. CONCLUSION: There is a tight linkage between methionine addiction and malignancy.
Assuntos
Transformação Celular Neoplásica/metabolismo , Neoplasias Pulmonares/metabolismo , Metionina/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/patologia , Humanos , Neoplasias Pulmonares/patologia , Camundongos Nus , Transdução de Sinais , Carga TumoralRESUMO
The precise mechanism of intercellular communication between cancer cells following radiation exposure is unclear. Exosomes are membraneenclosed small vesicles comprising lipid bilayers and are mediators of intercellular communication that transport a variety of intracellular components, including microRNAs (miRNAs or miRs). The present study aimed to identify novel roles of exosomes released from irradiated cells to neighboring cancer cells. In order to confirm the presence of exosomes in the human pancreatic cancer cell line MIAPaCa2, ultracentrifugation was performed followed by transmission electron microscopy and nanoparticle tracking analysis (NanoSight) using the exosomespecific surface markers CD9 and CD63. Subsequent endocytosis of exosomes was confirmed by fluorescent microscopy. Cell survival following irradiation and the addition of exosomes was evaluated by colony forming assay. Expression levels of miRNAs in exosomes were then quantified by microarray analysis, while protein expression levels of Cu/Zn and Mnsuperoxide dismutase (SOD1 and 2, respectively) enzymes in MIAPaCa2 cells were evaluated by western blotting. Results showed that the uptake of irradiated exosomes was significantly higher than that of nonirradiated exosomes. Notably, irradiated exosomes induced higher intracellular levels of reactive oxygen species (ROS) and a higher frequency of DNA damage in MIAPaCa2 cells, as determined by fluorescent microscopy and immunocytochemistry, respectively. Moreover, six up and five downregulated miRNAs were identified in 5 and 8 Gyirradiated cells using miRNA microarray analyses. Further analysis using miRNA mimics and reverse transcriptionquantitative PCR identified miR68235p as a potential candidate to inhibit SOD1, leading to increased intracellular ROS levels and DNA damage. To the best of our knowledge, the present study is the first to demonstrate that irradiated exosomes enhance the radiation effect via increasing intracellular ROS levels in cancer cells. This contributes to improved understanding of the bystander effect of neighboring cancer cells.
Assuntos
Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/radioterapia , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Comunicação Celular/fisiologia , Comunicação Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Dano ao DNA , Exossomos/genética , Exossomos/metabolismo , Exossomos/efeitos da radiação , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Tolerância a Radiação , Superóxido Dismutase-1/biossíntese , Superóxido Dismutase-1/metabolismoRESUMO
OBJECTIVES: Methionine addiction is a fundamental and general hallmark of cancer caused by enhanced methyl flux. In the present study, we effected a novel methionine-methylation blockade to target a patient-derived orthotopic xenograft model of pancreatic cancer. METHODS: The pancreatic cancer patient-derived orthotopic xenograft mouse models were randomized into 6 groups of 8 mice each and treated for 2 weeks: untreated control; azacitidine; oral recombinant methioninase (o-rMETase); o-rMETase plus cycloleucine; o-rMETase plus cycloleucine plus azacitidine (triple-methyl blockade therapy); and gemcitabine (positive control). RESULTS: Triple-methyl blockade therapy arrested tumor growth (mean relative tumor volume, 1.03 [standard deviation, 0.36]) and was significantly more effective compared with azacitidine (P = 0.0001); o-rMETase (P = 0.007); or o-rMETase plus cycloleucine (P = 0.04). Gemcitabine alone also inhibited but did not arrest tumor growth (mean relative tumor volume, 1.50 [standard deviation, 0.30]). The percentage of cancer cells that were negative for 5-methylcytosine staining in immunohistochemistry, indicating reduction of DNA methylation, increased with triple-methyl blockade therapy (37.5%), compared with gemcitabine (1.8%); o-rMETase (2.8%); azacitidine (9.0%); or o-rMETase plus cycloleucine (10.6%). CONCLUSIONS: This new concept of triple-methyl blockade therapy has clinical potential for pancreatic cancer, which is currently a recalcitrant disease.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Azacitidina/farmacologia , Liases de Carbono-Enxofre/farmacologia , Cicloleucina/farmacologia , Metionina/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Fibrose , Humanos , Camundongos Nus , Necrose , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Estudo de Prova de Conceito , Fatores de Tempo , Carga Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND/AIM: Exosomes are produced by normal and cancer cells. Exosomes are found in the serum of cancer patients and have been used for diagnosis and prognosis. Recently tears from non-cancer patients have been found to contain exosomes. In the present report we describe tears from advanced breast-cancer patients. MATERIALS AND METHODS: We found oncogenic miRNAs in the exosomes isolated from tear fluids obtained from five patients with metastatic breast cancer and compared them with tear exosomes form eight healthy volunteers. RESULTS: Tear exosomes had a significantly higher quantity of exosome markers than serum exosomes (CD9, CD63). Tear exosomes were subjected to quantitative reverse-transcription polymerase reaction (qRT-PCR), and western blot analysis to elucidate the status of miRNAs, previously reported in serum from patients with metastatic breast cancer. qRT-PCR and western-blot analysis revealed that breast-cancer-specific miR-21 and miR-200c were highly expressed in tear exosomes from metastatic breast cancer patients in contrast to tear exosomes from healthy volunteers. CONCLUSION: Tear exosomes can be a potential source of diagnostic and prognostic biomarkers for metastatic breast cancer, and possibly other cancers or diseases.
Assuntos
Neoplasias da Mama/genética , Carcinogênese/genética , Exossomos/genética , MicroRNAs/metabolismo , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Metástase NeoplásicaRESUMO
BACKGROUND/AIM: The discovery of the nude mouse model enabled the experimental growth of human-patient tumors. However, the low establishment rate of tumors in nude and other immunodeficient strains of mice has limited wide-spread clinical use. MATERIALS AND METHODS: In order to increase the establishment rate of surgical specimens of patient tumors, we transplanted tumors to nude mice subcutaneously along with large amounts of surrounding tissue of the tumor. RESULTS: The new transplantation method increased the establishment rate in nude mice to 66% compared to the old method of implanting the surgical tumor specimen with surrounding tissue removed (14%). High stage and presence of metastasis in the patient donor are positively correlated to tumor engraftment in nude mice. CONCLUSION: The new method can potentially allow most cancer patients who undergo surgery or biopsy to have their own mouse model for drug-sensitivity testing.
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Objetivos , Neoplasias , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Nus , Neoplasias/cirurgia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: To develop a novel biocompatible solid fiducial marker that prevents radiopaque imaging artifacts and also maintains high imaging contrast for kilovoltage x-ray image-guided radiation therapy. METHODS: The fiducial marker was made of pure zinc. An in-house water-equivalent phantom was designed to evaluate artifacts and visibility under various simulated treatment scenarios. Image artifacts were quantitatively assessed in terms of the metal artifact index (MAI) on kilovoltage computed tomography (CT) and cone-beam CT (CBCT) scans. Marker visibility was evaluated on two types of kilovoltage planar x-ray images in terms of the contrast-to-background ratio (CBR). Comparisons with a conventional gold fiducial marker were conducted. RESULTS: The use of zinc rather than a gold marker mitigates imaging artifacts. The MAI near the zinc marker decreased by 76, 79, and 77 % in CT, and by 77 (81), 74 (80), and 79 (85) % in CBCT full-fan (half-fan) scans, when using one-, two-, and three-marker phantom settings, respectively. The high-contrast part of the zinc marker exhibited CBRs above 2.00 for 28/32 exposures under four (lung, tissue, low-density bone, and high-density bone) different simulation scenarios, making its visibility comparable to that of the gold marker (30/32 exposures with CBRs > 2.00). CONCLUSIONS: We developed a biocompatible, artifact-robust, and highly visible solid zinc fiducial marker. Although further evaluation is needed in clinical settings, our findings suggest its feasibility and benefits for kilovoltage x-ray image-guided radiation therapy.
Assuntos
Marcadores Fiduciais , Radioterapia Guiada por Imagem , Artefatos , Tomografia Computadorizada de Feixe Cônico , Imagens de Fantasmas , Raios X , ZincoRESUMO
BACKGROUND/AIM: The direct placement of patient tumors in 2-D culture on plastic or glass surfaces has inhibited the establishment of patient-derived cancer cells (PDCCs). The aim of the present study was to develop universal and efficient methods to prepare PDCCs. MATERIALS AND METHODS: Fragments of patient-derived xenograft (PDX) tumors established form colon cancer liver metastasis (1 mm3) were placed on Gelfoam and cultured in DMEM. RESULTS: PDX tumor fragments were cultured on Gelfoam. Cancer cells migrated from the explant and formed distinct 3-D structures in the Gelfoam. Each of the three PDCCs showed a distinct morphology. The cultures were essentially all cancer cells without fibroblasts, the opposite of what usually occurs in 2-D culture on plastic or glass. Gelfoam cultures could be readily passaged from one Gelfoam cube to anothers suggesting indefinite culture potential. CONCLUSION: A potentially universal method to establish PDCC using PDX tumors and 3-D Gelfoam histoculture was developed.
Assuntos
Fibroblastos/patologia , Esponja de Gelatina Absorvível/farmacologia , Xenoenxertos/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Neoplasias do Colo/patologia , Fibroblastos/efeitos dos fármacos , Xenoenxertos/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/secundário , Camundongos Nus , Células Tumorais CultivadasRESUMO
BACKGROUND/AIM: obesity is a world-wide recalcitrant problem leading to many diseases. Dietary methionine restriction (MR) has been shown to prevent obesity, but it is an onerous regimen. The present study aimed to determine the effects of oral recombinant methionase (o-rMETase), on preventing obesity in mice on a high-fat diet. MATERIALS AND METHODS: Male C57BL/6J mice in the control group were fed a control diet (CD) (+6.5% fat) for 25 days, and others were fed a high-fat (HF) diet (+34.3% fat) for 25 days. Then, the mice were divided into three dietary groups: 1) HF + phosphate buffered saline (PBS) group; 2) HF + o-rMETase group; and 3) untreated non-HF group. RESULTS: The mice on the CD increased in body weight by 14% during experimental period of 25 days; in contrast the mice in the HF+PBS group increased by 33%; however, the mice on the HF+o-rMETase group increased only by 14% (p=0.02, HF+PBS vs HF+o-rMETase). CONCLUSION: The HF+ o-rMETase group had the same weight increase as untreated mice on a normal fat diet, demonstrating the potential for o-rMETase to eliminate the need for dieting to maintain normal body weight.