Early Diagnosis and Prognosis Prediction of Pancreatic Cancer Using Engineered Hybrid Core-Shells in Laser Desorption/Ionization Mass Spectrometry.

Effective detection of bio-molecules relies on the precise design and preparation of materials, particularly in laser desorption/ionization mass spectrometry (LDI-MS). Despite significant advancements in substrate materials, the performance of single-structured substrates remains suboptimal for LDI-MS analysis of complex systems. Herein, designer Au@SiO2@ZrO2 core-shell substrates are developed for LDI-MS-based early diagnosis and prognosis of pancreatic cancer (PC). Through controlling Au core size and ZrO2 shell crystallization, signal amplification of metabolites up to 3 orders is not only achieved, but also the synergistic mechanism of the LDI process is revealed. The optimized Au@SiO2@ZrO2 enables a direct record of serum metabolic fingerprints (SMFs) by LDI-MS. Subsequently, SMFs are employed to distinguish early PC (stage I/II) from controls, with an accuracy of 92%. Moreover, a prognostic prediction scoring system is established with enhanced efficacy in predicting PC survival compared to CA19-9 (p < 0.05). This work contributes to material-based cancer diagnosis and prognosis.

Identifying High Gleason Score Prostate Cancer by Prostate Fluid Metabolic Fingerprint-Based Multi-Modal Recognition.

Prostate cancer (PCa) is the second most common cancer in males worldwide. The Gleason scoring system, which classifies the pathological growth pattern of cancer, is considered one of the most important prognostic factors for PCa. Compared to indolent PCa, PCa with high Gleason score (h-GS PCa, GS ≥ 8) has greater clinical significance due to its high aggressiveness and poor prognosis. It is crucial to establish a rapid, non-invasive diagnostic modality to decipher patients with h-GS PCa as early as possible. In this study, ferric nanoparticle-assisted laser desorption/ionization mass spectrometry (FeNPALDI-MS) to extract prostate fluid metabolic fingerprint (PSF-MF) is employed and combined with the clinical features of patients, such as prostate-specific antigen (PSA), to establish a multi-modal diagnosis assisted by machine learning. This approach yields an impressive area under the curve (AUC) of 0.87 to diagnose patients with h-GS, surpassing the results of single-modal diagnosis using only PSF-MF or PSA, respectively. Additionally, using various screening methods, six key metabolites that exhibit greater diagnostic efficacy (AUC = 0.96) are identified. These findings also provide insights into related metabolic pathways, which may provide valuable information for further elucidation of the pathological mechanisms underlying h-GS PCa.

The molecular mechanism for human metallothionein-3 to protect against the neuronal cytotoxicity of Aß(1-42) with Cu ions.

Aggregation and cytotoxicity of Aß with redox-active metals in neuronal cells have been implicated in the progression of Alzheimer disease. Human metallothionein (MT) 3 is highly expressed in the normal human brain and is downregulated in Alzheimer disease. Zn(7)MT3 can protect against the neuronal toxicity of Aß by preventing copper-mediated Aß aggregation, abolishing the production of reactive oxygen species (ROS) and the related cellular toxicity. In this study, we intended to decipher the roles of single-domain proteins (α/ß) and the α-ß domain-domain interaction of Zn(7)MT3 to determine the molecular mechanism for protection against the neuronal cytotoxicity of Aß(1-42) with copper ions. With this in mind, the α and ß single-domain proteins, heterozygous ß(MT3)-α(MT1), and a linker-truncated mutant ∆31-34 were prepared and characterized. In the presence/absence of various Zn(7)MT3 proteins, the Aß(1-42)-Cu(2+)-mediated aggregation, the production of ROS, and the cellular toxicity were investigated by transmission electron microscopy, ROS assay by means of a fluorescent probe, and SH-SY5Y cell viability, respectively. The ß domain cannot abolish Aß(1-42)-Cu(2+)-induced aggregation, and neither the ß domain nor the α domain can quench the production of ROS because of the redox cycling of Aß-Cu(2+). Similarly to wild-type Zn(7)MT3, the heterozygous ß(MT3)-α(MT1) possesses the characteristic of alleviating Aß(1-42) aggregation and oxidative stress to neuronal cells. Therefore, the two domains through the linker Lys-Lys-Ser form a cooperative unit, and each of them is indispensable in conducting its bioactivity. The α domain plays an important role in modulating the stability of the metal-thiolate cluster, and the α-ß domain-domain interaction through the linker is critical for its protective role in the brain.

The mechanism for heme to prevent Aß(1-40) aggregation and its cytotoxicity.

The ß-amyloid peptide (Aß) aggregation in the brain, known as amyloid plaques, is a hallmark of Alzheimer's disease (AD). The aberrant interaction of Cu(2+) ion with Aß potentiates AD by inducing Aß aggregation and generating neurotoxic reactive oxygen species (ROS). In this study, the biosynthesized recombinant Aß(1-40) was, for the first time, used to investigate the mechanism for heme to prevent Aß(1-40) aggregation and its cytotoxicity. Cell viability studies of SH-SY5Y cells and rat primary hippocampal neurons showed that exogenous heme can protect the cells by reducing cytotoxicity in the presence of Cu(2+) and/or Aß(1-40). UV-vis spectroscopy, circular dichroism spectroscopy, and differential pulse voltammetry were applied to examine the interaction between heme and Aß(1-40). It was proven that a heme-Aß(1-40) complex is formed and can stabilize the α-helix structure of Aß(1-40) to inhibit Aß(1-40) aggregation. The heme-Aß(1-40) complex possesses peroxidase activity and it may catalyze the decomposition of H(2)O(2), reduce the generation of ROS downstream, and ultimately protect the cells. These results indicated that exogenous heme is able to alleviate the cytotoxicity induced by Aß(1-40) and Cu(2+). This information may be a foundation to develop a potential strategy to treat AD.

The Delta33-35 Mutant alpha-Domain Containing beta-Domain-Like M(3)S(9) Cluster Exhibits the Function of alpha-Domain with M(4)S(11) Cluster in Human Growth Inhibitory Factor.

Neuronal growth inhibitory factor (GIF), also known as metallothionein (metallothionein-3), impairs the survival and neurite formation of cultured neurons. It is known that the alpha-beta domain-domain interaction of hGIF is crucial to the neuron growth inhibitory bioactivity although the exact mechanism is not clear. Herein, the beta(MT3)-beta(MT3) mutant and the hGIF-truncated Delta33-35 mutant were constructed, and their biochemical properties were characterized by pH titration, EDTA, and DTNB reactions. Their inhibitory activity toward neuron survival and neurite extension was also examined. We found that the Delta33-35 mutant alpha-domain containing beta-domain-like M(3)S(9) cluster exhibits the function of alpha-domain with M(4)S(11) cluster in hGIF. These results showed that the stability and solvent accessibility of the metal-thiolate cluster in beta-domain is very significant to the neuronal growth inhibitory activity of hGIF and also indicated that the particular primary structure of alpha-domain is pivotal to domain-domain interaction in hGIF.