In-depth quantitative proteomics analysis revealed C1GALT1 depletion in ECC-1 cells mimics an aggressive endometrial cancer phenotype observed in cancer patients with low C1GALT1 expression

BACKGROUND

Endometrial cancer (EC) is the most common cancer of the female reproductive organs. Despite the good overall prognosis of most low-grade ECs, FIGO I and FIGO II patients might experience tumor recurrence and worse prognosis. The study of alterations related to EC pathogenesis might help to get insights into underlying mechanisms involved in EC development and progression.

METHODS

Core tumoral samples were used to investigate the role of C1GALT1 in EC by immunohistochemistry (IHC). ECC-1 cells were used as endometrioid EC model to investigate the effect of C1GALT1 depletion using C1GALT1 specific shRNAs. SILAC quantitative proteomics analyses and cell-based assays, PCR, qPCR, WB, dot-blot and IHC analyses were used to identify, quantify and validate dysregulation of proteins.

RESULTS

Low C1GALT1 protein expression levels associate to a more aggressive phenotype of EC. Out of 5208 proteins identified and quantified by LC-MS/MS, 100 proteins showed dysregulation (log2fold-change ≥ 0.58 or ≤-0.58) in the cell protein extracts and 144 in the secretome of C1GALT1 depleted ECC-1 cells. Nine dysregulated proteins were validated. Bioinformatics analyses pointed out to an increase in pathways associated with an aggressive phenotype. This finding was corroborated by loss-of-function cell-based assays demonstrating higher proliferation, invasion, migration, colony formation and angiogenesis capacity in C1GALT1 depleted cells. These effects were associated to the overexpression of ANXA1, as demonstrated by ANXA1 transient silencing cell-based assays, and thus, correlating C1GALT and ANXA1 protein expression and biological effects. Finally, the negative protein expression correlation found by proteomics between C1GALT1 and LGALS3 was confirmed by IHC.

CONCLUSION

C1GALT1 stably depleted ECC-1 cells mimic an EC aggressive phenotype observed in patients and might be useful for the identification and validation of EC markers of progression.

Pursuing precision in medicine and nutrition: the rise of electrochemical biosensing at the molecular level

In the era that we seek personalization in material things, it is becoming increasingly clear that the individualized management of medicine and nutrition plays a key role in life expectancy and quality of life, allowing participation to some extent in our welfare and the use of societal resources in a rationale and equitable way. The implementation of precision medicine and nutrition are highly complex challenges which depend on the development of new technologies able to meet important requirements in terms of cost, simplicity, and versatility, and to determine both individually and simultaneously, almost in real time and with the required sensitivity and reliability, molecular markers of different omics levels in biofluids extracted, secreted (either naturally or stimulated), or circulating in the body. Relying on representative and pioneering examples, this review article critically discusses recent advances driving the position of electrochemical bioplatforms as one of the winning horses for the implementation of suitable tools for advanced diagnostics, therapy, and precision nutrition. In addition to a critical overview of the state of the art, including groundbreaking applications and challenges ahead, the article concludes with a personal vision of the imminent roadmap.

Gold-silica hybrid nanolabels decorated with recognition and signaling bioreagents for enhanced electrochemical immunodetection of chemokine ligand-12 in colorectal cancer early diagnosis and monitoring

The use of gold-silica nanoconjugates (Au@SiO₂NCs) decorated with biotinylated detection antibodies (b-dAb) and horseradish peroxidase (HRP) is reported for the improved electrochemical immunosensing of chemokine ligand-12 (CXCL12), a relevant chemokine implicated in colorectal cancer (CRC) progression. Implemented on an amperometric sandwich immunoplatform the resulting nanobioconjugates provided significant signal amplification which is attributed to the high enzyme loading capacity and improved antibody orientation. The role played by each of the nanomaterials forming the nanohybrid was evaluated. Under optimized conditions, the developed immunoplatform exhibited a linear response ranging from 72 to 1000 pg mL-1, a 4 times higher sensitivity than the conventional labeling-based immunoplatform, a LOD of 22 pg mL-1, and a storage stability of 1 month. The immunoplatform was applied to the determination of CXCL12 in plasma from healthy individuals and CRC patients. The clinically relevant results obtained demonstrate the potential of plasma CXCL12 levels as a biomarker for both the early diagnosis of CRC and the monitoring of its progression.

Assessment of Microvascular Hemodynamic Adaptations in Finger Flexors of Climbers

Climbing performance is greatly dependent on the endurance of the finger flexors which, in turn, depends on the ability to deliver and use oxygen within the muscle. Near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) have provided new possibilities to explore these phenomena in the microvascular environment. The aim of the present study was to explore climbing-related microvascular adaptations through the comparison of the oxygen concentration and hemodynamics of the forearm between climbers and non-climber active individuals during a vascular occlusion test (VOT). Seventeen climbers and fifteen non-climbers joined the study. Through NIRS and DCS, the oxyhemoglobin (O2Hb) and deoxyhemoglobin (HHb) concentrations, tissue saturation index (TSI), and blood flow index (BFI) were obtained from the flexor digitorum profundus during the VOT. During the reactive hyperemia, climbers presented greater blood flow slopes (p = 0.043, d = 0.573), as well as greater O2Hb maximum values (p = 0.001, d = 1.263) and HHb minimum values (p = 0.009, d = 0.998), than non-climbers. The superior hemodynamics presented by climbers could indicate potential training-induced structural and functional adaptations that could enhance oxygen transportation to the muscle, and thus enhance muscle endurance and climbing performance.

Multifunctional cerium nanolabels in electrochemical immunosensing with improved robustness and performance: determination of TIM-1 in colorectal cancer scenarios as a case study

A multifunctional cerium oxide nanoparticles (CeO2NPs)-based nanolabel is exploited to implement an electrochemical sandwich-type immunoplatform for the determination of T-cell immunoglobulin and mucin domain 1 (TIM-1) biomarker, a mucin-like class I membrane glycoprotein associated with cancer angiogenesis. The immunoplatform is constructed using screen-printed electrodes where capture antibody is immobilized through the chemistry of diazonium salts. CeO2NPs exhibit robust pseudo-peroxidase activity even at high substrate concentrations. They are covalently functionalized in a simple manner after carboxylation with a detector antibody (dAb), acting dually as a nanozyme and nanocarrier for sensing bioreceptors. This allows the development of immunoplatforms with improved robustness and performance (in terms of a moderate enhancement in sensitivity, a significant expansion in the linear range, and a reduction in the background current) compared with the immunoplatforms prepared using nanolabels also decorated with the natural enzyme (horseradish peroxidase, HRP) or the conventional enzymatic labeling involving the dAb and an HRP-secondary antibody. Under the optimized experimental conditions, the developed electrochemical immunoplatform allows the highly sensitive detection of the TIM-1 glycoprotein, with a detection limit of 9.9 pg mL-1 and a linear working range of 33-600 pg mL-1. This performance permits biomarker quantification within clinically relevant ranges. This innovative configuration enables the precise diagnosis and stratification of colorectal cancer patients by analyzing plasma samples without pretreatment beyond a sample dilution and allows establishment of the first cut-off values reported for this purpose.

Breaking barriers in electrochemical biosensing using bioinspired peptide and phage probes

Electrochemical biosensing continues to advance tirelessly, overcoming barriers that have kept it from leaving research laboratories for many years. Among them, its compromised performance in complex biological matrices due to fouling or receptor stability issues, the limitations in determining toxic and small analytes, and its use, conditioned to the commercial availability of commercial receptors and the exploration of natural molecular interactions, deserved to be highlighted. To address these challenges, in addition to the intrinsic properties of electrochemical biosensing, its coupling with biomimetic materials has played a fundamental role, among which bioinspired phage and peptide probes stand out. The versatility in design and employment of these probes has opened an unimaginable plethora of possibilities for electrochemical biosensing, improving their performance far beyond the development of highly sensitive and selective devices. The state of the art offers robust electroanalytical biotools, capable of operating in complex samples and with exciting opportunities to discover and determine targets regardless of their toxicity and size, the commercial availability of bioreceptors, and prior knowledge of molecular interactions. With all this in mind, this review offers a panoramic, novel, and updated vision of both the tremendous advances and opportunities offered by the combination of electrochemical biosensors with bioinspired phage and peptide probes and the challenges and research efforts that are envisioned in the immediate future.

Contributing to the management of viral infections through simple immunosensing of the arachidonic acid serum level

A trendsetting direct competitive-based biosensing tool has been developed and implemented for the determination of the polyunsaturated fatty acid arachidonic acid (ARA), a highly significant biological regulator with decisive roles in viral infections. The designed methodology involves a competitive reaction between the target endogenous ARA and a biotin-ARA competitor for the recognition sites of anti-ARA antibodies covalently attached to the surface of carboxylic acid-coated magnetic microbeads (HOOC-MµBs), followed by the enzymatic label of the biotin-ARA residues with streptavidin-horseradish peroxidase (Strep-HRP) conjugate. The resulting bioconjugates were magnetically trapped onto the sensing surface of disposable screen-printed carbon transducers (SPCEs) to monitor the extent of the biorecognition reaction through amperometry. The operational functioning of the exhaustively optimized and characterized immunosensing bioplatform was highly convenient for the quantitative determination of ARA in serum samples from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2-) and respiratory syncytial virus (RSV)-infected individuals in a rapid, affordable, trustful, and sensitive manner.