ß-glucan therapy converts the inhibition of myeloid-derived suppressor cells in oral cancer patients.

OBJECTIVES: The myeloid-derived suppressor cells (MDSCs) frequently have a high expansion in cancer patients. This research explored whether administration of ß-glucan could increase anti-tumor immunity in oral squamous cell carcinoma (OSCC) patients. MATERIALS AND METHODS: This study evaluated the MDSC level of circulating blood as CD33+ /CD11b+ /HLA-DR-/low by flow cytometry in 30 healthy donors (HDs, group I), in 48 oral squamous cell carcinoma (OSCC) patients before and after 14-day preoperative administration of ß-glucan (group II), and in 52 OSCC patients without taking ß-glucan (group III). RESULTS: A significantly higher mean MDSC level was observed in 100 OSCC patients than in 30 HDs (p < .001). There was a significant reduction of the mean MDSC level in group II patients after taking ß-glucan (p < .001). Moreover, we discovered a significantly higher recurrence-free survival (RFS) in group II than in group III patients (p = .026). Finally, the multivariate Cox regression further identified the MDSC level ≤1% and administration of ß-glucan as more favorable prognostic factors for OSCC patients. CONCLUSION: Preoperative administration of ß-glucan can augment anti-tumor immunity and increase RFS rate via subversion of suppressive function of MDSC in OSCC patients.

Control the Single-, Two-, and Three-Photon Excited Fluorescence of Atomically Precise Metal Nanoclusters.

It remains challenging to control the single-, two-, and three-photon excited fluorescence of metal nanoclusters. In this work, the control over the non-linear optics of metal nanoclusters as single-, two-, and three-photon excited fluorescence has been accomplished via exploiting the solvent effect. An emissive nanocluster, Au9 Ag6 (SPht OMe)4 (DPPOE)3 Cl3 , was synthesized and structurally determined. The solvent effect can not only control the fluorescence of this nanocluster, but more significantly, it can also regulate the photoluminescence nature of the cluster as single-, two-, and three-photon excited fluorescence. We concluded that the increased solution polarity, improved dipole moment, enlarged HOMO-LUMO energy gap, and reduced solution viscosity of the cluster in solutions endow them with excellent high-order multiphoton excited fluorescence. The results provide an intriguing cluster template that enables us to manipulate the linear and nonlinear optics at the atomic level.

Au11Ag6 nanocluster: Controllable preparation, structural determination, and optical property investigation.

The structure/composition of nanoclusters has a decisive influence on their physicochemical properties. In this work, we obtained two different Au-Ag nanoclusters, [Au9Ag12(SAdm)4(dppm)6Cl6]3+ and Au11Ag6(dppm)4(SAdm)4(CN)4, via controlling the Au/Ag molar ratios by a one-pot synthetic approach. The structure of nanoclusters was confirmed and testified by single-crystal x-ray diffraction, electrospray ionization time-of-flight mass spectrometry, XPS, powder x-ray diffraction, and electron paramagnetic resonance. The Au11Ag6 nanocluster possessed a M13 core caped by four Au atoms and four dppm and four AdmS ligands. Interestingly, four CN are observed to locate at the equator of the M13 core. Both nanoclusters contain a similar icosahedral M13 core, whereas their surface structures are totally different. However, the Au11Ag6 nanocluster exhibits good stability and strong red photoluminescence in solution.

Rethinking the stability of metal nanoclusters: the individual versus the collective.

Research on the stability of metal nanoclusters and their molecular/supramolecular chemistry has proceeded significantly independently thus far. We herein have demonstrated that the stability of a nanocluster-based system should be assessed from both the cluster individual aspect (i.e., the energy of the molecular conformer) and the cluster collective aspect (i.e., the energy of the supramolecular lattice). A pair of Au2Cu6 cluster polymorphs, including Au2Cu6-triclinic and Au2Cu6-trigonal, was developed here to reveal the energy and stability contributions of both cluster conformers and crystalline lattices to their total systems. This work hopefully promotes a comprehensive understanding of the stability of cluster-based nano-systems which is beneficial for their downstream applications.

Probing the surface-active sites of metal nanoclusters with atomic precision: a case study of Au5Ag11.

The determination of surface-active sites in metal nanoclusters is of great significance for the in-depth understanding of structural evolutions and physicochemical property mechanisms. In this work, the surface-active sites of the Au5Ag11(DMBT)8(DPPOE)2 cluster template towards metal-/ligand-exchange reactions were unambiguously identified at the atomic level. The active-site tailoring of this nanocluster gave rise to three derivative nanoclusters, Au5Ag9Cu2(DMBT)8(DPPOE)2, Au5Ag11(DMBT)6(DCBT)2(DPPOE)2, and Au5Ag11(DCBT)8(DPPOE)2. The single-crystal structural analysis revealed that all these M16 (M = Au/Ag/Cu) clusters exhibited almost the same framework. Besides, the surface-active site tailoring contributed to significant changes in optical absorptions and emissions of these metal nanoclusters. The findings in this work not only provide an in-depth understanding of the active-site tailoring of cluster surface structures but also develop an intriguing template that enables us to grasp the structure-property correlations at the atomic level.

Horizontal expansion of biicosahedral M13-based nanoclusters: resolving decades-long questions.

For metal nanoclusters with the "cluster of clusters" intramolecular evolution pattern, most efforts have been made towards the vertical superposition of icosahedral nanobuilding blocks (e.g., from mono-icosahedral Au13 to bi-icosahedral Au25 and tri-icosahedral Au37), while the horizontal expansion of these rod-shaped multi-icosahedral aggregates was largely neglected. We herein report the horizontal expansion of the biicosahedral M25 cluster framework, yielding an [Au19Ag12(S-Adm)6(DPPM)6Cl7]2+ nanocluster that contains an Au13Ag12 kernel and six Au1(DPPM)1(S-Adm)1 peripheral wings. The structural determination of [Au19Ag12(S-Adm)6(DPPM)6Cl7]2+ resolved a decades-long question towards rod-shaped multi-icosahedral aggregates: how to load bidentate phosphine and bulky thiol ligands onto the nanocluster framework? The structural comparison between [Au19Ag12(S-Adm)6(DPPM)6Cl7]2+ and previously reported [Au13Ag12(PPh3)10Cl8]2+ or [Au13Ag12(SR)5(PPh3)10Cl2]2+ rationalized the unique packing of Au1(DPPM)1(S-Adm)1 motif structures on the surface of the former nanocluster. Overall, this work presents the horizontal expansion of rod-shaped multi-icosahedral nanoclusters, which provides new insights into the preparation of novel icosahedron-based aggregates with both vertically and horizontally growing extensions.

Reversible transformation between Au14Ag8 and Au14Ag4 nanoclusters.

Although several approaches have been exploited to trigger the structural transformation of metal nanoclusters, most cases are assigned to the unidirectional conversion, while the reversible conversion of nanoclusters remains challenging. In this work, the reversible conversion between two Au-Ag alloy nanoclusters, Au14Ag8(Dppm)6(CN)4Cl4 and Au14Ag4(Dppm)6Cl4, has been accomplished, which was tracked by UV-vis and ESI-MS spectroscopy. The condition of the nanocluster reversible conversion has been meticulously mapped out. Our results provide some new insights into the cluster transformation, which will benefit the future preparation of metalloid clusters with customized structures and properties.

Upregulated NPM1 is an independent biomarker to predict progression and prognosis of oral squamous cell carcinomas in Taiwan.

BACKGROUND: Nucleophosmin/nucleoplasmin family 1 (NPM1) has broad physiological functions, such as DNA replication, transcription, ribosome biogenesis, and centrosome replication. This study explored the clinicopathological importance of NPM1 as a prognostic marker for oral squamous cell carcinoma (OSCC). METHODS: We collected specimens from 96 OSCC, 45 oral epithelial dysplasia (OED), and 29 normal oral mucosa (NOM). NPM1 expression was analyzed via immunohistochemistry. Correlations between NPM1and clinical parameters were analyzed using Student t test, chi-squared test, and Kaplan-Meier product-limit method. RESULTS: The NPM1 labeling indices (LIs) were significantly higher in OSCCs than in NOM and oral OED. Higher NPM1 expression was significantly correlated with larger tumor size, nodal metastasis, and advanced clinical stage. Multivariate analysis revealed that higher NPM1 LIs were an unfavorable independent factor for survival. CONCLUSIONS: Upregulated NPM1 is an independent biomarker of poor prognosis and NPM1 inhibitors may be promising in molecular targeted therapy against OSCC.