MTFR2-dependent mitochondrial fission promotes HCC progression.

BACKGROUND: The role of mitochondrial dynamics, encompassing fission, fusion, and mitophagy, in cancer progression has been extensively studied. However, the specific impact of mitochondrial dynamics on hepatocellular carcinoma (HCC) is still under investigation. METHODS: In this study, mitochondrial dynamic genes were obtained from the MitoCarta 3.0 database, and gene expression data were collected from The Cancer Genome Atlas (TCGA) database. Based on the expression of these dynamic genes and differentially expressed genes (DEGs), patients were stratified into two clusters. Subsequently, a prognostic model was constructed using univariate COX regression and the least absolute shrinkage and selection operator (LASSO) regression, and the prognostic signature was evaluated. We analyzed the interaction between these model genes and dynamic genes to identify hub genes and reveal mitochondrial status. Furthermore, we assessed immune infiltration, tumor mutational burden (TMB), tumor stemness indices (TSI), and the response to immune checkpoint block (ICB) therapy using the TIDE algorithm and risk scores. Additionally, transmission electron microscopy (TEM), hematoxylin-eosin (H&E) staining, immunohistochemistry (IHC), western blotting (WB), and immunofluorescence (IF) were conducted to afford detailed visualization of the morphology of the mitochondria and the expression patterns of fission-associated proteins. RESULTS: Patients in Cluster 2 exhibited heightened mitochondrial fission and had a worse prognosis. The up-regulated dynamic genes in Cluster 2 were identified as fission genes. GO/KEGG analyses reconfirmed the connection of Cluster 2 to augmented mitochondrial fission activities. Subsequently, a ten-gene prognostic signature based on the differentially expressed genes between the two clusters was generated, with all ten genes being up-regulated in the high-risk group. Moreover, the potential links between these ten signature genes and mitochondrial dynamics were explored, suggesting their involvement in mediating mitochondrial fission through interaction with MTFR2. Further investigation revealed that the high-risk group had an unfavorable prognosis, with a higher mutation frequency of TP53, increased immune checkpoint expression, a higher TIS score, and a lower TIDE score. The mitochondrial imbalance characterized by increased fission and upregulated MTFR2 and DNM1L expression was substantiated in both HCC specimens and cell lines. CONCLUSIONS: In conclusion, we developed a novel MTFR2-related prognostic signature comprising ten mitochondrial dynamics genes. These genes play crucial roles in mitochondrial fission and have the potential to serve as important predictors and therapeutic targets for HCC.

Conformationally Preorganized High-Affinity Ligands for Copper Biology with Hinged and Rigid Thiophene Backbones.

Copper-selective ligands are essential tools for probing the affinity of cuproproteins or manipulating the cellular copper availability. They also harbor significant potential as antiangiogenic agents in cancer therapy or as therapeutics to combat copper toxicity in Wilson's disease. To achieve the high Cu(I) affinities required for competing effectively with cellular cuproproteins, we recently devised a ligand design based on phosphine-sulfide-stabilized phosphine (PSP) donor motifs. Building on this design strategy, we integrated two PSP donors within preorganized ligand architectures composed of either a hinged bithiophene backbone (bithipPS) or a single rigid thiophene bridge (thipPS). Extensive characterization based on X-ray crystal structures, solution NMR data, spectrophotometric titrations, and electrochemical studies established that bithipPS adapts well to the coordination preferences of Cu(I) to form a discrete air-stable mononuclear Cu(I) complex with a dissociation constant of 4 zM. In contrast, the wider bite angle of thipPS introduces some strain upon Cu(I) coordination to yield an almost 10-fold lower affinity with a Kd of 35 zM. As revealed by ICP-MS and two-photon excitation microscopy studies with the Cu(I)-selective fluorescent probe crisp-17, both ligands are effective at removing cellular copper from live mouse fibroblasts with rapid kinetics. Altogether, the stability and redox properties of PSP-ligand-Cu(I) complexes can be effectively tuned by judicious balancing of their geometrical preorganization and conformational flexibility.

Halide-Rebound Polymerization of Twisted Amides.

The first living polymerization of twisted amides is reported, achieved using simple primary alkyl iodides as initiators. Polymerization occurs through a halide-rebound mechanism in which the nucleophilic twisted amide is quaternized and subsequently ring-opened by the iodide counterion. The covalent electrophilic polymerization generates polymers with living chain ends that are both isolable and stable to ambient conditions, enabling the synthesis of block polymers. This presents a new class of polymers for study that possess high glass transition temperatures and robust thermal stability.

Generation of Sulfonyl Radicals from Aryldiazonium Tetrafluoroborates and Sulfur Dioxide: The Synthesis of 3-Sulfonated Coumarins.

A catalyst-free approach for the generation of sulfonyl radicals from aryldiazonium tetrafluoroborates in the presence of DABCO⋅(SO2 )2 is realized. The combination of aryldiazonium tetrafluoroborates, DABCO⋅(SO2 )2 , and aryl propiolates affords 3-sulfonated coumarins in good to excellent yields. This tandem reaction process involves radical addition, spirocyclization, and 1,2-migration of esters. Additionally, the in situ diazotization of a number of anilines allows the directional synthesis of desired 3-sulfonated coumarins in a one-pot, two-step process.

Multi-responsive poly-catecholamine nanomembranes.

The contraction of nanomaterials triggered by stimuli can be harnessed for micro- and nanoscale energy harvesting, sensing, and artificial muscles toward manipulation and directional motion. The search for these materials is dictated by optimizing several factors, such as stimulus type, conversion efficiency, kinetics and dynamics, mechanical strength, compatibility with other materials, production cost and environmental impact. Here, we report the results of studies on bio-inspired nanomembranes made of poly-catecholamines such as polydopamine, polynorepinephrine, and polydextrodopa. Our findings reveal robust mechanical features and remarkable multi-responsive properties of these materials. In particular, their immediate contraction can be triggered globally by atmospheric moisture reduction and temperature rise and locally by laser or white light irradiation. For each scenario, the process is fully reversible, i.e., membranes spontaneously expand upon removing the stimulus. Our results unveil the universal multi-responsive nature of the considered polycatecholamine membranes, albeit with distinct differences in their mechanical features and response times to light stimulus. We attribute the light-triggered contraction to photothermal heating, leading to water desorption and subsequent contraction of the membranes. The combination of multi-responsiveness, mechanical robustness, remote control via light, low-cost and large-scale fabrication, biocompatibility, and low-environment impact makes polycatecholamine materials promising candidates for advancing technologies.

Ion and Molecular Sieving With Ultrathin Polydopamine Nanomembranes.

In contrast to biological cell membranes, it is still a major challenge for synthetic membranes to efficiently separate ions and small molecules due to their similar sizes in the sub-nanometer range. Inspired by biological ion channels with their unique channel wall chemistry that facilitates ion sieving by ion-channel interactions, the first free-standing, ultrathin (10-17 nm) nanomembranes composed entirely of polydopamine (PDA) are reported here as ion and molecular sieves. These nanomembranes are obtained via an easily scalable electropolymerization strategy and provide nanochannels with various amine and phenolic hydroxyl groups that offer a favorable chemical environment for ion-channel electrostatic and hydrogen bond interactions. They exhibit remarkable selectivity for monovalent ions over multivalent ions and larger species with K+/Mg2+ of ≈4.2, K+/[Fe(CN)6]3- of ≈10.3, and K+/Rhodamine B of ≈273.0 in a pressure-driven process, as well as cyclic reversible pH-responsive gating properties. Infrared spectra reveal hydrogen bond formation between hydrated multivalent ions and PDA, which prevents the transport of multivalent ions and facilitates high selectivity. Chemically rich, free-standing, and pH-responsive PDA nanomembranes with specific interaction sites are proposed as customizable high-performance sieves for a wide range of challenging separation requirements.

Proton sponge-functionalized silica as high performance adsorbents for solid-phase extraction of trace perfluoroalkyl sulfonates in the environmental water samples and their direct analysis by MALDI-TOF-MS.

1,8-Bis(dimethylamino)naphthalene (DMAN), a classical 'proton sponge', was functionalized on silica particles as a novel solid-phase extraction (SPE) adsorbent (DMAN@silica) for extracting perfluoroalkyl sulfonates (PFSs). High reproducibility and excellent extraction capability for PFSs were obtained in a wide pH range (3.0~8.5). The adsorbed PFSs on DMAN@silica sorbents could be efficiently eluted by 1,8-bis(tetramethylguanidino)naphthalene (TMGN) solution which is a proton sponge with higher proton affinity than DMAN. The elution could be directly analyzed by MALDI-TOF-MS using TMGN as matrix. Clear mass spectra for the PFSs were obtained due to no matrix ions interference observed. Furthermore, a novel strategy based on the DMAN@silica-SPE enrichment, followed by MALDI-TOF-MS analysis, was proposed and applied for PFSs quantification in environmental water samples. The calibration curves of each of the target analytes showed a wide linear dynamic range of response (0.1-10 ng L(-1) for perfluorooctane sulfonate (PFOS), perfluorohexyl sulfonate (PFHxS) and perfluorobutylsulfonate (PFBS)), which were over 2 orders of magnitude. The detection limits for PFOS, PFHxS, and PFBS were 0.021, 0.016, and 0.013 ng L(-1), respectively (S/N = 3). Recoveries of PFOS, PFHxS, and PFBS are in the ranges of 92-104%, 95-102%, and 98-109% for spiked river water samples. These results indicated that the prepared DMAN@silica adsorbents could efficiently enrich PFSs and that the proposed method is reliable.

Photoacid generator formation for the selective enrichment of perfluoroalkyl sulfonates and their direct analysis by MALDI-TOF-MS.

Triphenylsulfonium chloride (TPSC) was employed as a bifunctional agent for the selective enrichment of perfluoroalkyl sulfonates by triphenylsulfonium perfluorosulfonic acid (TPA, a photoacid generator) precipitation, and for the direct detection of perfluorosulfonic acid by MALDI-TOF-MS, using the triphensylsulfonium group of TPA as a matrix.

[PAR-1 regulation of intracellular Ca²(+) mobilization in pulmonary giant cell carcinoma cell line PLA801D/PLA801C].

OBJECTIVES: To investigate molecular mechanisms of PAR-1 regulation on intracellular Ca²(+) mobilization in lung giant cell carcinoma cells in vitro and its involvement in tumor metastasis. METHODS: Free intracellular Ca²(+) ([Ca²(+)]i) was measured in lung giant cell carcinoma PLA801C and PLA801D cells by confocal microscopy. Sense and anti-sense PAR-1 expression vectors were transfected into PLA801C (C+)and PLA801D(D-) cells, respectively. The effects of PAR-1 expression were investigated by thrombin and TRAP-induced mobilization of [Ca²(+)]i in the C+ and D-cells. RESULTS: There were significant differences of the mean values of [Ca²(+)]i between PLA801D (59.55) and PLA801C cells (35.46, P < 0.01). The mean [Ca²(+)]i of C+ cells (45.77) was significantly higher than that of its control CV cells (35.46, P < 0.05), and the mean [Ca²(+)]i of D-cells (48.42) was significantly lower than that of its control DV cells (59.55, P < 0.05). The peaks of [Ca²(+)]i of C+ and CV cells were 48.19 ± 9.84 and 45.64 ± 9.87 (P < 0.05) respectively at 80 s and 100 s after thrombin treatment, but were 111.31 ± 25.00 and 52.93 ± 11.21 (P < 0.05) respectively at 60 s after TRAP treatment. The peaks of [Ca²(+)]i of D- and DV cells were 40.71 ± 5.89 and 61.07 ± 21.36 (P < 0.05) respectively at 60 s after thrombin treatment, but were 84.98 ± 11.23 and 102.58 ± 21.48 (P < 0.05) respectively at 40 s after TRAP treatment. CONCLUSIONS: The high metastatic potential of PLA801D and PLA801C may be related to [Ca²(+)]i of the tumor cells. PAR-1 may play an important role in the metastasis of lung giant cell carcinoma cells by up-regulating the intracellular Ca²(+).

[Clinicopathologic study of Churg-Strauss syndrome].

OBJECTIVE: To study the clinical and pathologic features of Churg-Strauss syndrome (CCS). METHODS: Three cases of Churg-Strauss syndrome, including 1 autopsy case and 2 cases with open thoracoscopic lung biopsy, were retrospectively reviewed. All the tissue samples were formalin-fixed, paraffin-embedded and stained with hematoxylin and eosin. RESULTS: The first patient was a 68-year-old man who had history of asthma for 4 years, with recent exacerbation and chest pain for 2 weeks. Patient died 1 day after admission due to myocarditis and myocardial infarction. He did not have peripheral eosinophilia, skin or paranasal sinus pathology. CSS represented an incidental autopsy finding and he had never been treated with corticosteroid before. The other 2 patients were a 58-year-old male and a 12-year-old female, respectively. Both had history of asthma, peripheral eosinophilia and lung consolidations on computed tomographic examination. Pathologically, all cases showed vasculitis, perivascular allergic-type granulomas, eosinophilic pneumonia and asthmatic bronchitis. CONCLUSIONS: Thorough understanding of the clinical and pathologic criteria is essential for arriving at a correct diagnosis of CSS. Although some patients may present with atypical symptoms, lung biopsies often reveal the classic histologic findings which include vasculitis and perivascular allergic granuloma formation.

[Epithelioid angiomyolipoma of kidney: clinicopathologic study of two cases and review of literature].

OBJECTIVE: To study the histopathologic features, differential diagnosis and prognosis of epithelioid angiomyolipoma (EAML) of kidney. METHODS: Two cases of EAML (including one case with recurrence) of kidney were retrieved from the archival files of Departments of Pathology, Navy General Hospital of PLA and Health Science Center of Peking University. The clinicopathologic features, immunohistochemistry, ultrastructural findings and follow-up data were studied and literature reviewed. RESULTS: Histologically, the tumors were predominantly composed of epithelioid cells with marked cellular pleomorphism. Focal perivascular arrangement was seen. Hemorrhage and necrosis were present and tumor emboli were found in the venous structures. The renal hilar lymph nodes were also involved by tumor cells. Immunohistochemical study showed that the tumor cells (including those in the hilar lymph nodes) were strongly and diffusely positive for HMB45, smooth muscle actin, neuron-specific enolase and vimentin. They were focally positive for S-100 protein, melan-pan and CD68. The staining for epithelial membrane antigen, AE1/3, CK7, CD117, muscle-specific actin, desmin, leukocyte common antigen, CD20, CD45RO, CD30, CD15, chromogranin A, synaptophysin, bcl-2, estrogen receptor, progesterone receptor and p53 were negative. Ultrastructural examination revealed the presence of melanosome-like dense granules, myofilaments and dense bodies in the tumor cell cytoplasm. Discontinuous and focally thickened basal lamina was seen surrounding the tumor cells. On follow up, both patients remained well and disease-free 10 months after operation. CONCLUSIONS: EAML is predominantly or almost entirely composed of epithelioid cells. Perivascular cellular arrangement, focal features of otherwise classic angiomyolipoma, as well as coexpression of HMB-45 and smooth muscle actin are clues to the correct diagnosis. The degree of cytologic atypia, presence of hemorrhage and necrosis and high mitotic activity may indicate the malignant potential of this tumor. On the other hand, the presence of lymph node involvement and even tumor emboli in renal veins may represent multifocaltumorigenicity rather than true malignancy. Definitive evidence of malignancy requires demonstration of distant metastasis.

[Functional aspects of protease-activated receptor 1 in promoting metastasis of lung cancer].

OBJECTIVE: To study the functional aspects of protease-activated receptor 1 (PAR-1) gene involved in tumor metastasis. METHODS: Two human lung giant cell carcinoma cell lines PLA801C (low metastasis potential) and PLA801D (high metastasis potential) were chosen as in-vitro human cancer model systems. Sense and anti-sense expression constructs of PAR-1 gene (pC/PAR1s and pC/PAR1as) were transfected into PLA-801C and PLA-801D cells by lipofection. PAR-1 expression was determined by RT-PCR and western blot analysis. MTT growth, flow cytometry analysis, fibronectin adhesion, and matrigel invasion assays were used to study the effect of PAR-1 expression on the proliferation, adhesion, and invasion of the transfected cells. RESULTS: Appropriate up-regulation or down-regulation of protein expression of PAR-1 was observed in both transfected cell lines (PLA801C and PLA801D) to express PAR-1s or PAR-1as, respectively. Expression of the sense PAR-1 markedly increased cellular proliferation, adhesion and invasion of PLA-801C cells. In contrast, anti-sense PAR-1 significantly inhibited cell growth, adhesion and invasion capabilities, along with cell arrest at G0/G1 phase of the PLA-801D cells. CONCLUSIONS: Successful up- and down- regulation of expression of PAR-1 can be achieved by in-vitro transfection of sense and antisense PAR-1 constructs. PAR-1 may enhance metastasis of lung cancer through its regulation of cellular proliferation, adhesion and invasion. Down-regulation of expression of PAR-1 may provide a new therapeutic strategy against lung carcinoma.

[Expression of PAR-1 in human lung carcinoma and its relationship with tumor metastatic potential].

OBJECTIVE: To explore the correlation between expression of PAR-1 and metastasis of human lung carcinoma. METHODS: Expression levels of PAR-1 were examined in surgically resected lung carcinoma specimens and corresponding lymph nodes by RT-PCR and immunohistochemistry, combined with morphometric methodology and clinicopathologic profiles. RESULTS: Strong PAR-1 staining was detected in the periphery of carcinoma nests, adenocarcinomatous emboli, foci of atypical adenomatous hyperplasia adjacent to the adenocarcinoma and atypical proliferation of duct epithelium of bronchial mucous glands. The expression rates of PAR-1 were 73.8% (59/80) and 63.9% (23/36) by immunohistochemistry and RT-PCR respectively. The percentage of PAR-1 protein expression cells was significantly higher in tumors with metastasis (85.7%, 48/56) than those without (45.8%, 11/24). Morphometric study demonstrated that there were significant differences of PAR-1 protein expression levels between tumors with metastatic and those without, primary and metastatic carcinomas, primary carcinomas and benign lung tissues adjacent to the carcinoma. No significant correlation was found between PAR-1 expression level and tumor size, histological types and tumor grades. The positive rate of PAR-1 mRNA expression in the metastatic group was significantly higher than that of the non-metastatic group (78.3%, 18/23 v.s. 38.5%, 5/13). CONCLUSION: PAR-1 expression may play an important role in determining the malignant phenotypes of lung cancers and significantly contribute to their initiation, progression and metastasis.

Extracellular matrix protein 1 (ECM1) is over-expressed in malignant epithelial tumors.

The extracellular matrix protein 1 (ECM1) is a secreted protein that has been implicated with cell proliferation, angiogenesis and differentiation. In the present study, we used immunohistochemical staining to examine the expression of ECM1 in a panel of human tumors and found that it was closely correlated with some types of tumors including: invasive breast ductal carcinoma (83%), esophageal squamous carcinoma (73%), gastric cancer (88%) and colorectal cancer (78%). Significantly, ECM1expression was correlated with the metastatic properties of the tumors. Primary breast cancers that had formed metastases were 76% positive while those that had not metastasized were only 33% positive. ECM1 expression was also correlated with PCNA a marker for proliferation, but not with CD34, a marker for endothelial cells. These results indicate that ECM1 tends to be preferentially expressed by metastatic epithelial tumors.

Effect of seawater immersion on plasma osmotic pressure and electrolyte balance following open chest trauma.

OBJECTIVE: To explore the effect of seawater immersion on serum osmotic pressure and electrolytes balance following chest trauma in dogs. METHODS: Twenty-five healthy adult dogs were used in the experiment. A canine model of right open pneumothorax was established by chest puncturing on all animals. Animals were divided into three groups: a control group (n=10) with chest trauma without any immersion; a seawater group (n=10) immersed in seawater after chest trauma and a normal saline group (n=5) immersed in normal saline solution following chest trauma. Blood samples were taken at different time intervals to determine plasma osmotic pressure and electrolytes. The hemodynamic changes were also recorded. RESULTS: Mortality in the seawater group was much higher than that of the control group and the normal saline group. The mean survival time in the seawater group lasted only 45 minutes, while in the control group and the normal saline group the average survival time was more than 4 hours (P<0.01). One of the most important causes of death was hypernatremia and high osmolality. Severe electrolytes imbalance was observed in seawater group. Hypernatremia and high osmolality were the most significant factors of high mortality in the seawater group. CONCLUSIONS: Seawater immersion after chest trauma appears to be associated with severe electrolyte imbalance as well as high osmotic pressure. These may be the risk factors leading to fatal outcome.

[Expression of PH20 in primary and metastatic breast cancer and its pathological significance].

OBJECTIVE: To evaluate the expression pattern of PH20 in primary and metastatic breast cancer and its relationship to tumor metastatic potential. METHODS: Anti-PH20 antibody was synthesized by injection of conjugated human PH20 peptides into rabbits. Immunohistochemical study was performed on 53 cases of human breast cancer. Western blot was used to detect PH20 expression in 5 cases of breast cancer with available fresh tissue. Two oligonucleotide probes were prepared for in-situ hybridization using breast tissue microarray. RESULTS: Normal breast tissue did not express PH20 (0/3), while 58.4% (31/53) of breast cancer cases did. The highest expression rate was found in metastatic foci in regional lymph nodes (83.3%), followed by primary breast cancer tissue in cases with lymph node secondaries (70.8%). The breast cancer cases with no any metastasis had an expression rate of 48.2%. The immunohistochemical staining results were further confirmed by Western blotting. In-situ hybridization showed PH20 RNA in 75% of the breast cancer tissue (21/28). Two of the 17 cases of normal breast tissue showed weak expression in some ductolobular units. CONCLUSIONS: The expression of PH20 has a positive correlation with metastatic potential in breast cancer. It is possible that PH20 may play an important role in the invasive growth and metastasis of breast cancer cells, via mechanisms such as digestion of surrounding stromal tissue and release of FGF-2.

[Thrombin and tumor metastasis - review].

Thrombin is a multifunctional serine protease that plays a key role in a variety of physiological and pathological conditions. In addition to the role in hemostasis and coagulation, thrombin has other numerous biological activities affecting inflammation, immune responses, tissue repair and wound healing. Apart from its physiological role thrombin activates the oncogenic potential of both normal and malignant cells and leads a metastatic phenotype. It is a potent mitogen for many tumor cells. It potentiates the proliferative response of tumor cells to some growth factors, increases the adhesive properties to the platelets and invasion processes of tumor cells to the extracellular matrix, enhances the metastatic capacity of tumor cells, activates angiogenesis and remodels the microenvironment of the tumor. The cellular biological effects of thrombin are mediated at least in part by a new subfamily of G-protein-coupled receptors designated proteinase-activited receptors (PARs). Thrombin has a bilateral effect on tumor cells:enhanced growth at low concentration, impaired growth/apoptosis at higher concentration. In this papers, the biological function of thrombin, thrombin and tumors, and thrombin receptors etc were reviewed.

Classification of gastric neuroendocrine tumors and its clinicopathologic significance.

AIMS:To study the pathologic classification of gastric neuroendocrine tumors and its clinicopathologic significance.METHODS:Paraffin-embedded sections of 52 gastric neuroendocrine tumors including 42 carcinoid tumors, and 10 cases of neuroendocrine carcinoma from 326 patients who underwent resection of stomach carcinomas were studied by immunohistochemical methods including 10 endocrine markers or hormones antibodies and endocrine cells in gastric neuroendocrine tumors and extratumoral mucosa were observed under electromicroscope.RESULTS:The 52 gastric neuroendocrine tumors were divided into three types:(1) Gastrin dependent type of carcinoid (26 cases) accompanied by chronic atrophic gastritis (CAG) and tumor extension limited to the mucosa or submucosa complicated with hypergastrinemia and G cell hyperplasia.This type was consistently preceded by and associated with generalized proliferation of endocrine cells in the extratomoral fundic mucosa.(2)Non-gastrin dependent type of carcinoids (16 cases)associated with neither CAG nor hypergastrinemia. This type was more aggressive; and (3)Neuroendocrie carcinomas (10 cases), which are highly aggressive tumors.CONCLUSIONS:A correct identification of different types of gastric endocrine tumors has major implications for the treatment and prognosis of the patients.