Circulating tumor cells (CTCs) and hTERT gene expression in CTCs for radiotherapy effect with lung cancer

Detection and isolation of viable cancer cells mediated by spytag and spycatcher using conditionally replicative adenovirus and magnetic microbeads

Circulating tumor cells (CTCs) are critical biomarkers for cancer diagnosis, prognosis, and therapy monitoring, but their rarity and reliance on surface markers limit detection and isolation. While conditionally replicative adenoviruses (crADs) enable tumor-selective targeting, their use has been limited to fluorescence-based detection without robust isolation of viable cells. To overcome this, we developed a crAD-based platform integrating SpyTag/SpyCatcher technology with SpyCatcher-decorated magnetic microbeads for marker-independent CTC detection and isolation. The engineered adenovirus (CR-Ad5-ST-GFP) selectively replicates in telomerase-positive tumor cells, expressing green fluorescent protein (GFP) and SpyTag under independent promoters. By leveraging the SpyTag/SpyCatcher interaction, our platform isolates CTCs without relying on surface markers, addressing epithelial-to-mesenchymal transition (EMT) and phenotype variations. In proof-of-concept experiments, A-549 and Ca Ski cells spiked into peripheral blood mononuclear cells (PBMCs) at 1:10,000 were detected and isolated with over 80% efficiency. The isolated cells remained viable and were successfully re-cultured, demonstrating their potential for downstream applications such as molecular profiling and drug sensitivity testing. This method advances crAD-based approaches by combining tumor-selective viral targeting with marker-independent, viable CTC isolation. Its compatibility with microfluidic systems makes it a promising tool for tumor monitoring and personalized cancer treatment.

Telomeres and telomerase in mesothelioma: Pathophysiology, biomarkers and emerging therapeutic strategies (Review)

Malignant mesothelioma (MM) is a rare but aggressive cancer linked to asbestos exposure and characterized by advanced‑stage disease at presentation. Despite advances in treatment, prognosis remains abysmal, highlighting the imperative for the development of novel biomarkers and treatment approaches. Telomere biology plays a pivotal role in the tumorigenic process and has emerged as a key area in oncology research. Short telomeres have been associated with genomic instability, and substantially shorter telomere length (TL) has been identified in MM, showcasing the potential of TL in risk assessment, early detection, and disease progression monitoring. MM predominantly maintains TL through telomerase activity (TA), which in research has been identified in >90% of MM cases, underscoring the potential of TA as a biomarker in MM. Telomerase reverse transcriptase (TERT) polymorphisms may serve as valuable biomarkers, with research identifying associations between single nucleotide polymorphisms (SNPs) and the risk and prognosis of MM. Additionally, TERT promoter mutations have been associated with poor prognosis and advanced‑stage disease, with the non‑canonical functions of TERT hypothesized to contribute to the development of MM. TERT promoter mutations occur in ~12% of MM cases; C228T, C250T and A161C are the most common, while the distribution and frequency differ depending on histological subtype. Research reveals the promise of the various approaches therapeutically targeting telomerase, with favorable results in pre‑clinical models and inconclusive findings in clinical trials. The present review examines the role of telomere biology in MM and its implications in diagnosis, prognosis, and therapy.

Constructing a highly sensitive duplex immunoassay using AuNPs and AgNPs as nanolabels for investigating the epithelial-mesenchymal transition occurring on circulating tumor cells with lung cancer patients

Transformation of epithelial to mesenchymal (EMT) is an important event in the process of tumor initiation, invasion and metastasis. Circulating tumor cells (CTCs) are one kind of important markers in the field of liquid tumor biopsy, whose number and phenotype represent the occurrence and progression of tumors. Therefore, it is our interest to investigate the epithelial mesenchymal transition process occurring on the surface of CTCs. Herein in this work, two proteins of E-cadherin (E-cad) and N-cadherin (N-cad) were selected as representative proteins of EMT process. To achieve simultaneous analysis of E-cad and N-cad on the surface of rare CTCs, we designed a duplex and portable immunosensor using AuNPs and AgNPs as nanolabels to amplify the immunoreaction signals. The dual channel immunosensor not only exhibited good electrochemical responses for recombinant E-cad and N-cad as low as 0.1 ng/mL and 0.05 ng/mL, respectively, but also showed good linear correlations with different numbers of phenotypic CTCs (10-500 cells/10 μL). The above strategy was further employed to inspect the occurrence of EMT on CTCs surface, which displayed a high consistence with other molecular biological characterizations. Finally, this immunoassay was successfully applied to inspect the correlations of numbers, phenotype of CTCs, as well as E-cad and N-cad expressions on these CTCs in bloods of NSCLC patients with disease stage.

Particle Beam Radiobiology Status and Challenges: A PTCOG Radiobiology Subcommittee Report

Particle therapy (PT) represents a significant advancement in cancer treatment, precisely targeting tumor cells while sparing surrounding healthy tissues thanks to the unique depth-dose profiles of the charged particles. Furthermore, their linear energy transfer and relative biological effectiveness enhance their capability to treat radioresistant tumors, including hypoxic ones. Over the years, extensive research has paved the way for PT's clinical application, and current efforts aim to refine its efficacy and precision, minimizing the toxicities. In this regard, radiobiology research is evolving toward integrating biotechnology to advance drug discovery and radiation therapy optimization. This shift from basic radiobiology to understanding the molecular mechanisms of PT aims to expand the therapeutic window through innovative dose delivery regimens and combined therapy approaches. This review, written by over 30 contributors from various countries, provides a comprehensive look at key research areas and new developments in PT radiobiology, emphasizing the innovations and techniques transforming the field, ranging from the radiobiology of new irradiation modalities to multimodal radiation therapy and modeling efforts. We highlight both advancements and knowledge gaps, with the aim of improving the understanding and application of PT in oncology.

Circulating Tumor Cell Phenotype Detection and Epithelial-Mesenchymal Transition Tracking Based on Dual Biomarker Co-Recognition in an Integrated PDMS Chip

Circulating tumor cells (CTCs) are widely considered as a reliable and promising class of markers in the field of liquid biopsy. As CTCs undergo epithelial-mesenchymal transition (EMT), phenotype detection of heterogeneous CTCs based on EMT markers is of great significance. In this report, an integrated analytical strategy that can simultaneously capture and differentially detect epithelial- and mesenchymal-expressed CTCs in bloods of non-small cell lung cancer (NSCLS) patients is proposed. First, a commercial biomimetic polycarbonate (PCTE) microfiltration membrane is employed as the capture interface for heterogenous CTCs. Meanwhile, differential detection of the captured CTCs is realized by preparing two distinct CdTe quantum dots (QDs) with red and green emissions, attached with EpCAM and Vimentin aptamers, respectively. For combined analysis, a polydimethylsiloxane (PDMS) chip with simple structure is designed, which integrates the membrane capture and QDs-based phenotype detection of CTCs. This chip not only implements the analysis of the number of CTCs down to 2 cells mL-1, but enables EMT process tracking according to the specific signals of the two QDs. Finally, this method is successfully applied to inspect the correlations of numbers or proportions of heterogenous CTCs in 94 NSCLS patients with disease stage and whether there is distant metastasis.

Exploiting the metabolic vulnerability of circulating tumour cells

Metastasis has a major part in the severity of disease and lethality of cancer. Circulating tumour cells (CTCs) represent a reservoir of metastatic precursors in circulation, most of which cannot survive due to hostile conditions in the bloodstream. Surviving cells colonise a secondary site based on a combination of physical, metabolic, and oxidative stress protection states required for that environment. Recent advances in CTC isolation methods and high-resolution 'omics technologies are revealing specific metabolic pathways that support this selection of CTCs. In this review, we discuss recent advances in our understanding of CTC biology and discoveries of adaptations in metabolic pathways during their selection. Understanding these traits and delineating mechanisms by which they confer acquired resistance or vulnerability in CTCs is crucial for developing successful prognostic and therapeutic strategies in cancer.

Liquid biopsy techniques and lung cancer: diagnosis, monitoring and evaluation

Lung cancer stands as the most prevalent form of cancer globally, posing a significant threat to human well-being. Due to the lack of effective and accurate early diagnostic methods, many patients are diagnosed with advanced lung cancer. Although surgical resection is still a potential means of eradicating lung cancer, patients with advanced lung cancer usually miss the best chance for surgical treatment, and even after surgical resection patients may still experience tumor recurrence. Additionally, chemotherapy, the mainstay of treatment for patients with advanced lung cancer, has the potential to be chemo-resistant, resulting in poor clinical outcomes. The emergence of liquid biopsies has garnered considerable attention owing to their noninvasive nature and the ability for continuous sampling. Technological advancements have propelled circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), extracellular vesicles (EVs), tumor metabolites, tumor-educated platelets (TEPs), and tumor-associated antigens (TAA) to the forefront as key liquid biopsy biomarkers, demonstrating intriguing and encouraging results for early diagnosis and prognostic evaluation of lung cancer. This review provides an overview of molecular biomarkers and assays utilized in liquid biopsies for lung cancer, encompassing CTCs, ctDNA, non-coding RNA (ncRNA), EVs, tumor metabolites, TAAs and TEPs. Furthermore, we expound on the practical applications of liquid biopsies, including early diagnosis, treatment response monitoring, prognostic evaluation, and recurrence monitoring in the context of lung cancer.