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BACKGROUND: The tumor microenvironment (TME) is a critical player in tumor progression, metastasis and therapy outcomes. Tumor-associated macrophages (TAMs) are a well-recognized core element of the TME and generally characterized as M2-like macrophages. TAMs are believed to contribute to tumor progression, but the mechanism behind this remains unclear. We aimed to investigate the clinical, angiogenic, and lymphangiogenic significance of TAMs in non-small cell lung cancer (NSCLC). METHODS: Utilizing combined immunohistochemistry and digital image analysis, we assessed CD68, CD163, VEGF-A, and VEGF-C expression in 349 patients with NSCLC. Subsequently, the potential association between M2 TAMs and angiogenic VEGF-A and/or lymphangiogenic VEGF-C was evaluated for its prognostic value. Furthermore, the effects of M2 TAMs on angiogenesis and lymphangiogenesis were explored via an in vitro co-culture system. RESULTS: CD68 and CD163 expression were found to directly correlate with VEGF-A and/or VEGF-C expression (all p < 0.001). Furthermore, elevated M2 ratio (CD163+/CD68+) was significantly associated with poor overall survival (p = 0.023). Dual expression of M2 ratiohigh and VEGF-Chigh (M2 ratiohighVEGF-Chigh) was correlated with worse overall survival (p = 0.033). Multivariate analysis revealed that M2 ratiohigh [HR (95% CI) = 1.53 (1.01-2.33), p = 0.046] and combined M2 ratiohighVEGF-Chigh expression [HR (95% CI) = 2.01 (1.28-3.16), p = 0.003] were independent predictors of poor overall survival. Notably, we confirmed that M2 macrophages significantly enhanced the protein and mRNA expression of both VEGF-A and VEGF-C, while M1 macrophages induced only mRNA expression of VEGF-A in A549 cells. CONCLUSIONS: This study suggests that TAMs are significantly associated with angiogenesis and lymphangiogenesis, contributing to the progression of NSCLC. Furthermore, elevated M2 ratio, similar to combined high M2 ratio and high VEGF-C expression, is a strong indicator of poor prognosis in patients with NSCLC, providing insight for future TAM-based immunotherapy strategies.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Linfangiogênese , Prognóstico , Microambiente Tumoral , Macrófagos Associados a TumorRESUMO
Removal of excessive melanin from heavily pigmented formalin-fixed paraffin-embedded (FFPE) melanoma tissues is essential for histomorphological and molecular diagnostic assessments. Although there have been efforts to address this issue, current methodologies remain complex and time-consuming, and are not suitable for multiple molecular applications. Herein, we have developed a robust and rapid melanin-bleaching methodology for FFPE tissue specimens. Our approach is based on quick bleaching (15 min) at high temperature (80 °C) with 0.5% diluted hydrogen peroxide (H2O2) in Tris-HCl, PBS, or Tris/Tricine/SDS buffer. Immunostaining for Ki-67 and HMB45 was enhanced by bleaching with 0.5% H2O2 in Tris/Tricine/SDS and Tris-HCl, respectively. In addition to histopathological applications, our approach also facilitates recovery of protein and nucleic acid from archival melanin-rich FFPE tissue sections. Protein extracted from bleached FFPE tissues was compatible with western blotting using anti-human GAPDH and AKT antibodies. Our bleaching condition significantly improved RNA quality compared with unbleached tissues without compromising the yield. Notably, the RNA/DNA obtained from bleached tissues was suitable for end point PCR and real-time quantitative RT-PCR. In conclusion, this improved melanin-bleaching method enhances and simplifies immunostaining procedures, and facilitates the use of melanin-rich FFPE tissues for histomorphological and PCR amplification-based molecular assays.
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Técnicas Histológicas , Temperatura Alta , Peróxido de Hidrogênio , Melaninas , Formaldeído , Humanos , Inclusão em ParafinaRESUMO
BACKGROUND: The human epidermal growth factor receptor-2 (HER-2) expression level is a critical element for determining the prognosis and management of breast cancer. HER-2 targeted therapy in breast cancer depends on the reliable assessment of HER-2 expression status but current standard methods are lacking a rigorous quantitative assay. To address this challenge, we developed an assessment of HER-2 expression method by well-based reverse phase protein array (RPPA). RESULTS: Well-based RPPA is based on a robust protein isolation methodology paired with a novel electrochemiluminescence detection system. HER-2 value of well-based RPPA significantly correlated with dot blotting results (R(2) = 0.939). By well-based RPPA, we successfully detected HER-2 expression in 76 human breast formalin-fixed paraffin-embedded tissue samples. We observed 93.4% (71/76) concordance between well-based RPPA and current HER-2 immunohistochemical assessment guideline. When the cutoff level of HER-2 value was set to 0.689 (HER-2/GAPDH) on the basis of receiver-operating characteristic curve, the area under the curve was 0.975 (95% CI, 0.941-1.000). Sensitivity and specificity of well-based RPPA was 92.1% and 94.7%, respectively. CONCLUSIONS: HER-2 value by well-based RPPA was correlated with the current HER-2 status guideline, suggesting that this normalized HER-2 assessment may offer advantages over unnormalized current immunohistochemical assessment methods.
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Immunotherapies are revolutionizing cancer care, but many patients do not achieve durable responses and immune-related adverse events are difficult to predict. Quantifying the hundreds of proteins involved in cancer immunity has the potential to provide biomarkers to monitor and predict tumor response. We previously developed robust, multiplexed quantitative assays for immunomodulatory proteins using targeted mass spectrometry, providing measurements that can be performed reproducibly and harmonized across laboratories. Here, we expand upon those efforts in presenting data from a multiplexed immuno-oncology (IO)-3 assay panel targeting 43 peptides representing 39 immune- and inflammation-related proteins. A suite of novel monoclonal antibodies was generated as assay reagents, and the fully characterized antibodies are made available as a resource to the community. The publicly available dataset contains complete characterization of the assay performance, as well as the mass spectrometer parameters and reagent information necessary for implementation of the assay. Quantification of the proteins will provide benefit to correlative studies in clinical trials, identification of new biomarkers, and improve understanding of the immune response in cancer.
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Anticorpos Monoclonais , Espectrometria de Massas , Neoplasias , Humanos , Anticorpos Monoclonais/imunologia , Imunoterapia , Neoplasias/imunologiaRESUMO
OBJECTIVE: We investigated the clinical significance of ERp57 in the progression of cervical cancer. METHODS: mRNA and protein expression of ERp57 in cervical neoplasias were examined. RESULTS: ERp57 mRNA expression was significantly decreased in cervical cancers. Immunohistochemistry revealed that ERp57 expression in 123 cervical cancers was down-regulated compared to cervical intraepithelial neoplasias or normal tissues (p < 0.001). Low ERp57 expression was significantly associated with worse overall survival (HR = 12.19, p = 0.018). CONCLUSIONS: Low ERp57 expression independently predicts a poor outcome for patients with cervical cancer, supporting the notion that ERp57 may be a promising novel cancer target.
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Expressão Gênica , Isomerases de Dissulfetos de Proteínas/genética , Displasia do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/metabolismo , Adulto , Idoso , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Isomerases de Dissulfetos de Proteínas/metabolismo , Transporte Proteico , Análise Serial de Tecidos , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/mortalidade , Displasia do Colo do Útero/patologiaRESUMO
Neutral buffered formalin (NBF) is the most common fixative in clinical applications. However, NBF damages proteins and nucleic acids, limiting the quality of proteomic and nucleic acid-based assays. Prior studies have demonstrated that BE70, a fixative of buffered 70% ethanol, has many benefits over NBF but the degradation of proteins and nucleic acids in archival paraffin blocks remain a challenge. Thus, we evaluated the addition of guanidinium salts to BE70 with the hypothesis that this may protect RNA and protein. Guanidinium salt supplemented BE70 (BE70G)-fixed tissue is comparable with that of BE70 via histology and immunohistochemistry. Western blot analysis also revealed that HSP70, AKT, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression signals in BE70G-fixed tissue were higher than those in BE70-fixed tissue. The quality of nucleic acids extracted from BE70G-fixed, paraffin-embedded tissue was also superior, and BE70G provides improved protein and RNA quality at shorter fixation times than its predecessors. The degradation of proteins, AKT and GAPDH, in archival tissue blocks is also decreased with the addition of guanidinium salt to BE70. In conclusion, BE70G fixative improves the quality of molecular analysis with more rapid fixation of tissue and enhanced long-term storage of paraffin blocks at room temperature for evaluation of protein epitopes.
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Ácidos Nucleicos , Proteômica , Fixadores , Guanidina , Inclusão em Parafina , Parafina , Proteínas Proto-Oncogênicas c-akt , Formaldeído , RNA/análise , Fixação de TecidosRESUMO
Although the immunogenicity of formalin-fixed paraffin-embedded tissue sections can decrease during storage and transport, the exact mechanism of antigenic loss and how to prevent it are not clear. Herein, we investigated changes in the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), E-cadherin, and Ki-67 in human breast tissue microarray (TMA) tissue sections stored for up to 3 months in dry and wet conditions. The positive rates of ER and PR expression were minimally changed after 3 months of storage, but the Allred scores of ER and PR stored in humid conditions decreased remarkably in comparison to fresh-cut tissue. The HER-2 antigenicity and RNA integrity of breast TMA sections stored in dry conditions diminished gradually with storage time, whereas the immunoreactivity and RNA quality of HER-2 in humid conditions decreased sharply as storage length increased. The area and intensity of E-cadherin staining in tissue sections stored in dry conditions did not change significantly and were minimally changed after 3 months, respectively. In contrast, the area and intensity of E-cadherin staining in tissue sections stored in humid conditions decreased significantly as storage length increased. Finally, the Ki-67 labeling index of tissue sections stored for 3 months in dry (9% decrease) and wet (31.9% decrease) conditions was decreased in comparison to fresh sections. In conclusion, these results indicate that water is a crucial factor for protein and RNA degradation in stored tissue sections, and detailed guidelines are required in the clinic.
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Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Imuno-Histoquímica , Antígeno Ki-67/genética , Inclusão em Parafina , Formaldeído , Caderinas/genéticaRESUMO
Introduction: Immunotherapy is an effective treatment for a subset of cancer patients, and expanding the benefits of immunotherapy to all cancer patients will require predictive biomarkers of response and immune-related adverse events (irAEs). To support correlative studies in immunotherapy clinical trials, we are developing highly validated assays for quantifying immunomodulatory proteins in human biospecimens. Methods: Here, we developed a panel of novel monoclonal antibodies and incorporated them into a novel, multiplexed, immuno-multiple reaction monitoring mass spectrometry (MRM-MS)-based proteomic assay targeting 49 proteotypic peptides representing 43 immunomodulatory proteins. Results and discussion: The multiplex assay was validated in human tissue and plasma matrices, where the linearity of quantification was >3 orders of magnitude with median interday CVs of 8.7% (tissue) and 10.1% (plasma). Proof-of-principle demonstration of the assay was conducted in plasma samples collected in clinical trials from lymphoma patients receiving an immune checkpoint inhibitor. We provide the assays and novel monoclonal antibodies as a publicly available resource for the biomedical community.
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BACKGROUND: Accurate CNS tumor diagnosis can be challenging, and methylation profiling can serve as an adjunct to classify diagnostically difficult cases. METHODS: An integrated diagnostic approach was employed for a consecutive series of 1258 surgical neuropathology samples obtained primarily in a consultation practice over 2-year period. DNA methylation profiling and classification using the DKFZ/Heidelberg CNS tumor classifier was performed, as well as unsupervised analyses of methylation data. Ancillary testing, where relevant, was performed. RESULTS: Among the received cases in consultation, a high-confidence methylation classifier score (>0.84) was reached in 66.4% of cases. The classifier impacted the diagnosis in 46.7% of these high-confidence classifier score cases, including a substantially new diagnosis in 26.9% cases. Among the 289 cases received with only a descriptive diagnosis, methylation was able to resolve approximately half (144, 49.8%) with high-confidence scores. Additional methods were able to resolve diagnostic uncertainty in 41.6% of the low-score cases. Tumor purity was significantly associated with classifier score (P = 1.15e-11). Deconvolution demonstrated that suspected glioblastomas (GBMs) matching as control/inflammatory brain tissue could be resolved into GBM methylation profiles, which provided a proof-of-concept approach to resolve tumor classification in the setting of low tumor purity. CONCLUSIONS: This work assesses the impact of a methylation classifier and additional methods in a consultative practice by defining the proportions with concordant vs change in diagnosis in a set of diagnostically challenging CNS tumors. We address approaches to low-confidence scores and confounding issues of low tumor purity.
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Neoplasias do Sistema Nervoso Central , Glioblastoma , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/genética , Metilação de DNA , Glioblastoma/diagnóstico , Glioblastoma/genética , HumanosRESUMO
Purpose To better enable communication among researchers, clinicians, and caregivers, we aimed to assess how untrained listeners classify early infant vocalization types in comparison to terms currently used by researchers and clinicians. Method Listeners were caregivers with no prior formal education in speech and language development. A 1st group of listeners reported on clinician/researcher-classified vowel, squeal, growl, raspberry, whisper, laugh, and cry vocalizations obtained from archived video/audio recordings of 10 infants from 4 through 12 months of age. A list of commonly used terms was generated based on listener responses and the standard research terminology. A 2nd group of listeners was presented with the same vocalizations and asked to select terms from the list that they thought best described the sounds. Results Classifications of the vocalizations by listeners largely overlapped with published categorical descriptors and yielded additional insight into alternate terms commonly used. The biggest discrepancies were found for the vowel category. Conclusion Prior research has shown that caregivers are accurate in identifying canonical babbling, a major prelinguistic vocalization milestone occurring at about 6-7 months of age. This indicates that caregivers are also well attuned to even earlier emerging vocalization types. This supports the value of continuing basic and clinical research on the vocal types infants produce in the 1st months of life and on their potential diagnostic utility, and may also help improve communication between speech-language pathologists and families.
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Linguagem Infantil , Fonação/fisiologia , Fala/classificação , Fala/fisiologia , Adulto , Feminino , Audição , Humanos , Lactente , Masculino , Adulto JovemRESUMO
RAS genes are frequently mutated in cancer and have for decades eluded effective therapeutic attack. The National Cancer Institute's RAS Initiative has a focus on understanding pathways and discovering therapies for RAS-driven cancers. Part of these efforts is the generation of novel reagents to enable the quantification of RAS network proteins. Here we present a dataset describing the development, validation (following consensus principles developed by the broader research community), and distribution of 104 monoclonal antibodies (mAbs) enabling detection of 27 phosphopeptides and 69 unmodified peptides from 20 proteins in the RAS network. The dataset characterizes the utility of the antibodies in a variety of applications, including Western blotting, immunoprecipitation, protein array, immunohistochemistry, and targeted mass spectrometry. All antibodies and characterization data are publicly available through the CPTAC Antibody Portal, Panorama Public Repository, and/or PRIDE databases. These reagents will aid researchers in discerning pathways and measuring expression changes in the RAS signaling network.
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Anticorpos Monoclonais/química , Genes ras , Transdução de Sinais , Linhagem Celular , Impressões Digitais de DNA , Humanos , Indicadores e Reagentes/química , Repetições de Microssatélites , Neoplasias/genéticaRESUMO
Formalin-fixed paraffin-embedded (FFPE) tissue is the predominant preparation for diagnostic histopathological evaluation and increasingly the biospecimen on which molecular diagnostics are performed. However, formalin is carcinogenic and results in cross-linking of proteins and nicking and alterations of nucleic acids. Alternative fixatives, including 70% ethanol, improved biomolecular integrity; however, they have yet to replace neutral-buffered formalin (NBF). Herein, we describe the phosphate-buffered ethanol 70% (BE70) fixative. The histomorphology of BE70-fixed tissue is very similar to that of NBF; however, it is a non-cross-linking fixative and lacks the carcinogenic profile of formaldehyde-based fixatives. RNA isolated from tissue fixed in BE70 was of substantially higher quality and quantity than that was recovered from formalin-fixed tissue. Furthermore, the BE70 fixative showed excellent RNA and DNA integrity compared with that of NBF fixative based on real-time polymerase chain reaction analysis results. Immunohistochemical staining was similar for the antigen tested. In conclusion, BE70 is a non-cross-linking fixative that is superior to NBF and 70% ethanol with reference to biomolecule recovery and quality from paraffin-embedded tissue. Additional studies to compare the histomorphologic and immunohistochemical performance and utility in a clinical setting are required.
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Etanol , Fixadores , Fosfatos , Animais , Soluções Tampão , DNA/análise , Técnicas Histológicas , Rim/química , Rim/citologia , Camundongos , Proteínas/análise , RNA/análise , Fixação de Tecidos/métodosRESUMO
BACKGROUND: The differential diagnosis of benign and malignant effusion is often hampered by low cell content or insufficiently preserved tumor cells. In this study, we evaluated the combined diagnostic value of six tumor markers measured by well-based reverse-phase protein array (RPPA) for diagnosis of malignant effusion. METHODS: A total of 114 patients (46 with malignant effusions, 32 with probable malignant effusions, and 36 with benign effusions) were enrolled. Expressional levels of MUC1, EMA, Pan-CK, HSP90, TGF-ß and CA125 were determined by well-based RPPA. RESULTS: Median relative expression of MUC1, Pan-CK and EMA were significantly higher in malignant effusion than those in probable malignant or benign (p < 0.001, p = 0.003, p < 0.001, respectively), whereas the level of TGF-ß in malignant effusions were significantly lower than that in the other groups (p = 0.005). For predicting malignancy, EMA presented the best areas under the curve of 0.728 followed by MUC1 of 0.701. The sensitivity of 52.0% for MUC1 and 48.0% for EMA were not better than cytology. However, sensitivity, negative predictive value, and accuracy of the tumor marker panel were better than cytology by 14.7%, 7.5%, and 6.1%, respectively. CONCLUSIONS: Tumor marker panel measured by well-based RPPA showed values in the differential diagnosis between benign and malignant effusions. Further large scale studies need to be performed to evaluate the utility of this panel of markers. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1433424467160224.
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Biomarcadores Tumorais/análise , Derrame Pleural Maligno/química , Derrame Pleural Maligno/diagnóstico , Derrame Pleural/diagnóstico , Derrame Pleural/metabolismo , Análise Serial de Proteínas , Área Sob a Curva , Análise por Conglomerados , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Derrame Pleural/etiologia , Derrame Pleural Maligno/etiologia , Valor Preditivo dos Testes , Curva ROCRESUMO
INTRODUCTION: The purpose of this study was to evaluate the ability of 4 different warm vertical compaction protocols to obturate artificially created defects in the apical one-third of a root canal system by using a split-tooth model. METHODS: Four warm vertical protocols used (A) continuous down-pack and continuous backfill, (B) continuous down-pack and incremental backfill, (C) incremental down-pack and continuous backfill, and (D) incremental down-pack and incremental backfill. Three artificially created defects were placed 2, 3, and 4 mm from the apex of the split-tooth model. Before obturations, a fine-medium System B plugger was prefitted 4 mm from the working length. The root canal system was obturated according to each of the experimental protocols. Resultant obturations (N = 10/protocol) were separated from the model, and replicated defects were assessed by a blinded evaluator who used an ordinal scale (0-4) that was based on how much each defect was replicated by GP. RESULTS: By using nonparametric analyses with Bonferroni adjustment (α = 0.01), with the apical 2-mm defect, protocol D demonstrated significantly (P ≤ .01) better defect replication as compared with protocols A, B, and C. For the apical 3-mm defect, protocols B and D were significantly better (P ≤ .01) than protocols A and C. However, there was no difference (P > .01) between protocols with apical 4-mm defect (100% replication). CONCLUSIONS: The incremental down-pack with incremental backfill appears better able to replicate the most apical defect, which suggests benefits of repeated heat application and packing force to manipulate the GP in the apical plug area.
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Cavidade Pulpar/patologia , Guta-Percha/química , Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/métodos , Ápice Dentário/patologia , Temperatura Alta , Humanos , Teste de Materiais , Microscopia/instrumentação , Obturação do Canal Radicular/instrumentação , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Propriedades de SuperfícieRESUMO
The tumor suppressor gene ARID1A encodes BAF250a, a component of human SWI/SNF chromatin-remodeling complexes. Loss of BAF250a expression has recently been reported in several tumor types. To investigate the potential correlation between BAF250a and various clinicopathologic parameters, we assessed the expression of BAF250a in archival tumor tissue specimens from 147 patients with cervical cancer and 191 with cervical intraepithelial neoplasia as well as 376 matched nonadjacent normal tissues by immunohistochemical staining. Messenger RNA expression level for BAF250a was decreased in cervical cancer cell lines (P = .013) and tissues (P = .010), when compared with normal cervical epithelial tissue using SYBR Green real-time polymerase chain reaction. BAF250a was also detected in nuclear fractions of HeLa cells and in nuclei of cervical cancer tissue samples by Western blotting and immunohistochemistry, respectively. BAF250a expression gradually decreased in transitioning from normal to cervical carcinoma (P < .001), and this loss of expression was significantly associated with tumor stage (P = .005), tumor grade (P = .029), tumor size (P = .003), and lymph node metastasis (P = .020). In multivariate analysis, overall survival in cervical cancer was significantly reduced in cases with BAF250a loss (hazard ratio, 2.78 [1.01-7.63]; P = .047). Our findings suggest a potential role for BAF250a in providing valuable prognostic information to clinicians for risk assessment in cervical cancer.
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Adenocarcinoma/secundário , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Ligação a DNA , Progressão da Doença , Feminino , Células HeLa , Humanos , Linfonodos/patologia , Metástase Linfática , Proteínas Nucleares/genética , Taxa de Sobrevida , Análise Serial de Tecidos , Fatores de Transcrição/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/mortalidade , Displasia do Colo do Útero/genética , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/mortalidadeRESUMO
Alzheimer's disease (AD) is a progressive mental disorder disease, which affects 26.6 million people worldwide and estimated increments can be 100 millions by 2050. Since there is no cure at present, early diagnosis of AD is crucial for the current drug treatments. Driven by the need, here we demonstrate for the first time that monoclonal anti-tau antibody-coated gold nanoparticle based two-photon scattering assay can be used for the detection of Alzheimer's tau protein in the 1 pg/mL level which is about 2 orders of magnitude lower than cutoff values (195 pg/mL) for tau protein in CSF (cerebrospinal fluid). We have shown that when anti-tau antibody-coated gold nanoparticles were mixed with 20 ng/mL of tau protein, two-photon Rayleigh scattering intensity (TPRS) increases by about 16 times. The mechanism of TPRS intensity change has been discussed. Our data demonstrated that our TPRS assay is highly sensitive to tau protein and it can distinguish from BSA, which is one of the most abundant protein components in CSF. Our results demonstrate the potential for a broad application of this type of nanobionanotechnology in practical biomedical applications.