Sensitivity For Diagnosis Of Cancer Research Articles

DNA Logic Circuits for Cancer Theranostics

Cancer diagnosis and therapeutics (theranostics) based on the tumor microenvironment (TME) and biomarkers has been an emerging approach for precision medicine. DNA nanotechnology dynamically controls the self-assembly of DNA molecules at the nanometer scale to construct intelligent DNA chemical reaction systems. The DNA logic circuit is a particularly emerging approach for computing within the DNA chemical systems. DNA logic circuits can sensitively respond to tumor-specific markers and the TME through logic operations and signal amplification, to generate detectable signals or to release anti-cancer agents. In this review, the fundamental concepts of DNA logic circuits are clarified, the basic modules in the circuit are summarized, and how this advanced nano-assembly circuit responds to tumor-related molecules, how to perform logic operations, to realize signal amplification, and selectively release drugs through discussing over 30 application examples, are demonstrated. This review shows that DNA logic circuits have powerful logic judgment and signal amplification functions in improving the specificity and sensitivity of cancer diagnosis and making cancer treatment controllable. In the future, researchers are expected to overcome the existing shortcomings of DNA logic circuits and design smarter DNA devices with better biocompatibility and stability, which will further promote the development of cancer theranostics.

Glyco-CPLL: An Integrated Method for In-Depth and Comprehensive N-Glycoproteome Profiling of Human Plasma.

N-glycoproteins are involved in various biological processes. Certain distinctive glycoforms on specific glycoproteins enhance the specificity and/or sensitivity of cancer diagnosis. Therefore, the characterization of plasma N-glycoproteome is essential for a new biomarker discovery. The absence of suitable analytical methods for in-depth and large-scale analyses of low-abundance plasma glycoproteins makes it challenging to investigate the role of glycosylation. In this study, we developed an integrated method termed Glyco-CPLL, which integrates combinatorial peptide ligand libraries, high-pH reversed-phase prefractionation, hydrophilic interaction chromatography, trypsin and PNGase F digestion, shotgun proteomics, and various analysis software (MaxQuant and pGlyco2.0) for the low-abundance plasma glycoproteomic profiling. Then, we utilized the method to perform a comparative study and to explore papillary thyroid carcinoma-related proteins and glycosylations with reference to healthy controls. Finally, a large and comprehensive human plasma N-glycoproteomic database was established, containing 786 proteins, 369 N-glycoproteins, 862 glycosites, 171 glycan compositions, and 1644 unique intact N-glycopeptides. Additionally, several low-abundance plasma glycoproteins were identified, including SVEP1 (∼0.54 ng/mL), F8 (∼0.83 ng/mL), and ADAMTS13 (∼1.2 ng/mL). These results suggest that this method will be useful for analyzing plasma intact glycopeptides in future studies. Besides, the Glyco-CPLL method has a great potential to be translated to clinical applications. Data are available via ProteomeXchange with identifier PXD016428.

In Vivo Flow Cytometry of Circulating Tumor-Associated Exosomes.

Circulating tumor cells (CTCs) demonstrated the potential as prognostic markers of metastatic development. However, the incurable metastasis can already be developed at the time of initial diagnosis with the existing CTC assays. Alternatively, tumor-associated particles (CTPs) including exosomes can be a more valuable prognostic marker because they can be released from the primary tumor long before CTCs and in larger amount. However, little progress has been made in high sensitivity detection of CTPs, especially in vivo. We show here that in vivo integrated photoacoustic (PA) and fluorescence flow cytometry (PAFFC) platform can provide the detection of melanoma and breast-cancer-associated single CTPs with endogenously expressed melanin and genetically engineered proteins or exogenous dyes as PA and fluorescent contrast agents. The two-beam, time-of-light PAFFC can measure the sizes of CTCs and CTPs and identify bulk and rolling CTCs and CTC clusters, with no influence on blood flow instability. This technique revealed a higher concentration of CTPs than CTCs at an early cancer stage. Because a single tumor cell can release many CTPs and in vivo PAFFC can examine the whole blood volume, PAFFC diagnostic platform has the potential to dramatically improve (up to 105-fold) the sensitivity of cancer diagnosis.

Diagnostic Utility of Unbiased Circulating Tumour Cell Capture through Negative Depletion of Peripheral Blood Cells

Objectives: Cytological analysis of peripheral blood circulating tumour cells (CTCs) is a potential method of confirmatory clinical diagnosis of cancer. However, cell capture methods tend to be biased and captured cells are not usually portable resulting in difficulties in pathology reporting. We evaluated unbiased cell capture through depletion of unwanted normal cells and conventional clinical analyses of captured cells. Methods: Blood was sampled from 29 patients who underwent surgery for suspected lung cancer. It was processed using two different depletion cocktails. After depletion of unwanted cells, the resultant cell pellet was processed onto glass slides or embedded into FFPE blocks and stained using standard haematoxylin and eosin staining followed by cytopathologic assessment. Two pathologists performed the assessment independently. Results: The CTCs were identified in 38-45% of cases using CD45 depletion cocktail with the cell pellet processed on a glass slide, while other combinations of methods produced poorer results. Overall, there was a good concordance between the pathologists (up to 91.3%). The sensitivity of cancer diagnosis was 42% (95% CI 23-63%), while the specificity was 100% (95% CI 29-100%). Conclusion: Negative depletion can be used to isolate CTCs in standard clinical settings; however, more effective ways of detection are required to increase the sensitivity of the diagnosis.

Imaging of bronchioloalveolar carcinoma in the mice with the αⅤβ3 integrin-targeted tracer 99mTc-RGD-4CK

Receptor-based imaging agents have shown improved specificity and sensitivity of cancer diagnosis by targeting the specific features of cancer. Here we reported the (99m)Tc-labeling of a cyclic polypeptide RGD-4CK and the characterization of this agent in vitro and in bronchioloalveolar carcinoma (BAC) xenograft model. The αⅤβ3 integrin receptor binding affinity of (99m)Tc-RGD-4CK was determined in BAC. The cancer targeting properties of (99m)Tc-RGD-4CK were determined in NCI-H358 xenografted nude mice. Moreover, the BAC uptake of (99m)Tc-RGD-4CK was blocked with nonradiolabeled RGD-4CK in xenografts. The competitive assay showed that (99m)Tc-RGD-4CK exhibited high specificity to BAC cell line NCI-H358. Biodistribution studies indicated that (99m)Tc-RGD-4CK exhibited high tumor uptake (4.12 ± 1.21% injected dose/g 120 minutes after injection) and prolonged tumor retention (2.08 ± 0.33% injected dose/g 240 minutes after injection) in NCI-H358 xenografted nude mice. Moreover, (99m)Tc-RGD-4CK produced a good tumor-to-lung ratio (2.38) because of low lung activity accumulation 120 minutes postinjection. BAC on the flank of xenografted mice was clearly visualized by single photon emission computed tomography/computed tomography imaging using (99m)Tc-RGD-4CK. In conclusion, this study provides evidence that (99m)Tc-RGD-4CK is a promising agent for noninvasive determination of αⅤβ3 integrin status and therapy monitoring in BAC.

Recent Trends in Multifunctional Liposomal Nanocarriers for Enhanced Tumor Targeting

Liposomes are delivery systems that have been used to formulate a vast variety of therapeutic and imaging agents for the past several decades. They have significant advantages over their free forms in terms of pharmacokinetics, sensitivity for cancer diagnosis and therapeutic efficacy. The multifactorial nature of cancer and the complex physiology of the tumor microenvironment require the development of multifunctional nanocarriers. Multifunctional liposomal nanocarriers should combine long blood circulation to improve pharmacokinetics of the loaded agent and selective distribution to the tumor lesion relative to healthy tissues, remote-controlled or tumor stimuli-sensitive extravasation from blood at the tumor's vicinity, internalization motifs to move from tumor bounds and/or tumor intercellular space to the cytoplasm of cancer cells for effective tumor cell killing. This review will focus on current strategies used for cancer detection and therapy using liposomes with special attention to combination therapies.

Usefulness of Endobronchial Ultrasonography for Transbronchial Lung Biopsies of Peripheral Lung Lesions

Background: Peripheral lung lesions are increasing in numbers. Endoscopic diagnosis is essential for the prevention of unnecessary operations. Conventional diagnostic procedures have limitations in availability and results. Objectives: Endobronchial ultrasonography (EBUS) was investigated as a means to guide transbronchial lung biopsy, to reduce the discomfort during the procedure and to improve diagnostic accuracy. Methods: In 50 cases, we performed transbronchial lung biopsy combined with EBUS and fluoroscopic guidance. The results were compared to 42 controls assessed by fluoroscopy only. Results: In 38 cases (76%), EBUS could describe the peripheral lesion (33 from inside, including 9 cases with difficulties in fluoroscopic observation, and 5 from an adjacent bronchus, indicating the correct location of the lesion). If successfully placed inside, a change in the patient’s position was not required, which helped to reduce patient discomfort. Lung cancer was diagnosed in 24 patients and benign disease in 25 patients; in 1 case diagnosis remained unknown. When the EBUS probe could be introduced inside the lesion, the sensitivity for cancer diagnosis and specificity for cancer exclusion were 100%, respectively (15/15, 18/18). Compared to the controls in whom the biopsy site was determined by fluoroscopy only, the sensitivity tended to be superior by EBUS, although it did not reach statistical significance (p = 0.06). However, specificity and accuracy were statistically significant (both p = 0.02). Conclusions: When the lesion can be correctly described by EBUS from inside the lesion, EBUS is useful to guide transbronchial lung biopsy, can contribute to a reduction in patient discomfort and improves the accuracy of diagnosis. Additional navigation tools to increase correct positioning of the EBUS probe are desirable.

Tumor-associated antigen arrays to enhance antibody detection for cancer diagnosis

Cancer sera contain antibodies which react with a unique group of autologous cellular antigens called tumor-associated antigens (TAAs). Cancer has long been recognized as a multi-step process which involves not only genetic changes conferring growth advantage but also factors which disrupt regulation of growth and differentiation. It is possible that some of these factors could be identified and their functions evaluated with the aid of autoantibodies arising during tumorigenesis. The multi-factorial and multi-step nature in the molecular pathogenesis of human cancers must be taken into account in both the design and interpretation of studies to identify biomarkers which will be useful for early detection of cancer. Our recent studies suggest that the combination of antibodies against a group of TAAs might acquire higher sensitivity for diagnosis of cancer. It is conceivable that autoantibody profiles involving different panels or arrays of TAAs might be developed in the future and the results could be useful for cancer diagnosis.