Comparison of clinicopathological features between cerebral cystic and alveolar echinococcosis: analysis of 27 cerebral echinococcosis cases in Xinjiang, China.

BACKGROUND: Cerebral echinococcosis is relatively rare, and it is important to distinguish cerebral cystic echinococcosis (CCE) from cerebral alveolar echinococcosis (CAE) in terms of pathological diagnosis. We aim to describe the different clinicopathological features among patients with CCE and CAE. METHODS: We collected 27 cases of cerebral echinococcosis which were diagnosed in the Department of Pathology of the First Affiliated Hospital of Xinjiang Medical University from January 1, 2012, to June 30, 2023. We compared the patients' clinical characteristics, MRI features, and pathologic manifestations of CCE and CAE. RESULTS: Among 27 cases of cerebral echinococcosis, 23 cases were CAE and 4 cases were CCE. The clinical manifestations of both CCE and CAE patients mainly included headache (21 patients, 77.78%), limb movement disorders (6 patients, 22.22%), epileptic seizures (4 patients, 14.81%) and visual disturbances (2 patients, 7.41%). The average onset age of CAE cases was 34.96 ± 11.11 years, which was 9.00 ± 7.26 years in CCE cases. All CAE patients presented with multiple involvements in the brain and extracranial organs while all CCE patients observed a solitary lesion in the brain and 3 CCE cases had no extracranial involvement. Lesions of CCE in MRI showed a single isolated circular, which was well demarcated from the surrounding tissues and with no obvious edema around the lesions, whereas CAE lesions presented as multiple intracranial lesions, with blurred edges and edema around the lesions, and multiple small vesicles could be observed in the lesions. The edge of CAE lesions could be enhanced, while CCE lesions have no obvious enhancement. CCE foci were clear cysts with a wall of about 0.1 cm. Microscopically, the walls of the cysts were characterized by an eosinophilic keratin layer, which was flanked on one side by basophilic germinal lamina cells, which were sometimes visible as protocephalic nodes. While the CAE lesion was a nodular structure with a rough and uneven nodule surface, and the cut section was cystic and solid; microscopically, the CAE lesion had areas of coagulative necrosis, and the proto-cephalic nodes were barely visible. Inflammatory cell areas consisting of macrophages, lymphocytes, epithelioid cells, plasma cells, eosinophils, and fibroblasts can be seen around the lesion. Brain tissues in the vicinity of the inflammatory cell areas may show apoptosis, degeneration, necrosis, and cellular edema, while brain tissues a little farther away from the lesion show a normal morphology. CONCLUSIONS: With the low incidence of brain echinococcosis, the diagnosis of echinococcosis and the differential diagnosis of CAE and CCE are challenging for pathologists. Grasping the different clinical pathology characteristics of CAE and CCE is helpful for pathologists to make accurate diagnoses.

Erratum: Overexpression of ZEB1 and YAP1 is related to poor prognosis in patients with gliomas with different IDH1 status.

[This corrects the article on p. 138 in vol. 16, PMID: 37559682.].

Overexpression of ZEB1 and YAP1 is related to poor prognosis in patients with gliomas with different IDH1 status.

OBJECTIVE: Whether there is a correlation between zinc-finger E-box-binding homolog 1 (ZEB1) and Yes-associated protein 1 (YAP1) with clinical outcome in gliomas remains unclear. Hence, this study aimed to investigate the effects of ZEB1 and YAP1 on the prognosis of human gliomas and its relationship with the isocitrate dehydrogenase 1 (IDH1) gene state. METHODS: Immunohistochemical staining was used to record the expression levels of ZEB1, YAP1, and p-YAP1 in 122 cases of low-grade glioma (LGGs) and 69 cases of glioblastoma (GBMs). The correlations of ZEB1 and YAP1 with pathological data were determined by Pearson's Chi-square test. Spearman correlation analysis was then used for analyzing the relationship among YAP1, ZEB1, and IDH1 gene status. The effects of ZEB1 and YAP1 on prognosis were investigated through survival analysis. RESULTS: We detected high ZEB1 expression levels in 29 LGGs (23.8%) and 39 GBMs (56.5%), and high YAP1 expression levels in 22 LGGs (18.0%) and 44 of GBM (63.8%). These results revealed that the protein expression levels of ZEB1 and YAP1 were higher in GBM (P < 0.001). There was a significantly positive correlation between ZEB1 and YAP1 (P < 0.001; r = 0.533). High ZEB1 expression was related to tumor grade (P < 0.001) and Ki-67 (P = 0.0037). YAP1 overexpression was correlated with Ki-67 (P < 0.001), P53 (P = 0.009), tumor grade (P < 0.001), and tumor location (P = 0.018). Patients with ZEB1 and YAP1 high expression had worse overall survival (OS) (P < 0.001). The multivariate analysis showed that YAP1 was an independent prognostic factor for OS. In the LGG group, worse OS were observed in glioma patients with elevated YAP1 expression level. Spearman correlation analysis revealed no association between ZEB1 expression and IDH1 state (P = 0.360; r = -0.084), and YAP1 expression had a negative correlation with IDH1 mutation (P < 0.001, r = -0.364). CONCLUSIONS: Our study showed that ZEB1 and YAP1 were significantly activated in GBM, and patients with high ZEB1 and YAP1 expression had worse OS. ZEB1 expression was significantly correlated with YAP1 in glioma. ZEB1 and YAP1 coexpression may serve as a useful prognostic biomarker for glioma, and aberrant YAP1 expression may be associated with IDH1 gene state.

Lower PTEN may be associated with CD8+ T cell exhaustion in diffuse large B-cell lymphoma.

Initially discovered in chronic viral infection and then extended to tumor, 'T-cell exhaustion' is a broad term describing the response of T cells to chronic antigen stimulation. By definition, whether T-cell exhaustion occurs in diffuse large B-cell lymphoma (DLBCL) remains largely unknown because little has been described. Here, the immune-suppressing checkpoint molecules involved in T-cell exhaustion, including PD-1, PD-L1, TIM-3 and TIGIT, whose expression levels were analyzed in DLBCL, were retrieved from the GEPIA database. Compared with the normal control, CD8A, TNFA, IFNG and GZMA were markedly elevated in DLBCL, indicating that infiltrated CD8+ T cells predominate in DLBCL. Meanwhile, inhibitory immune checkpoints, such as PD-1, PD-L1, TIGIT and TIM-3 were drastically higher in DLBCL. PTEN, WNT2 and DKK3 expression were also appraised. It was revealed that PTEN was lower in DLBCL, without being statistically significant. In contrast with PTEN, DKK3 and WNT2 were shown to be pronouncedly higher in DLBCL relative to the normal control. Prognostically, only TIGIT was found to be associated with overall survival in DLBCL. Collectively, all the data we curetted from the GEPIA and TIMER 2.0 databases explicitly indicate that CD8+ T cell exhaustion took place, which may be linked with lower PTEN in DLBCL. To the best of our knowledge, this is the first bioinformatic report explicitly proposing that CD8+ T cell exhaustion occurs in DLBCL, which may be associated with lower PTEN.

Expression and prognostic analysis of STAT6(YE361) in Hodgkin lymphoma.

This study aimed to investigate the expression and prognostic significance of the signal transducer and activator of transcription protein 6 (STAT6YE361) and EB virus encoding a small molecule RNA (EBER) in Hodgkin lymphoma (HL), as well as their correlation with clinical parameters. The expression of STAT6YE361 and EBER was investigated in HL via immunohistochemistry and in situ hybridization. Patient clinical data were retrospectively collected from archival libraries, and statistical analysis was performed. Overall, the nuclear positive expression rate of STAT6YE361 was 46%, and the EBER positive expression rate was 57%. STAT6YE361 was specifically expressed on the nucleus in cHL tissues. EBER was overexpressed in HL and had correlations with several clinical data, including age, gender, ethnicity, and primary cancer site. Interestingly, nuclear STAT6YE361 expression was correlated with EBER expression. Based on survival analysis, the nuclear expression of STAT6YE361 and female patients were associated with poor prognosis and were independent prognostic factors for five-year OS. These findings suggest that STAT6YE361 is a potential valuable index in the differential diagnosis and prognosis of HL. The mechanism of STAT6YE361 is related to Epstein-Barr virus infection.

Screening and identification of differentially expressed microRNAs in diffuse large B-cell lymphoma based on microRNA microarray.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of B-cell non-Hodgkin lymphoma in adults and the pathogenesis of DLBCL is multifactorial and complex. Understanding the molecular mechanisms involved in DLBCL is important to identify new therapeutic targets. The present study aimed to screen and identify differentially expressed microRNAs (miRNAs/miRs) between diffuse large B-cell lymphoma (DLBCL) and control [lymph node reactive hyperplasia (LRH)] groups, and to investigate whether miRNAs associated with DLBCL could serve as potential therapeutic targets. In total, 5 DLBCL experimental samples and 5 control samples were obtained from fresh patient tissues. Firstly, the fresh samples were analyzed using miRNA microarray to identify differentially expressed miRNAs. Next, three databases (TargetScan, microRNA.org and PITA) were used to predict by intersection the potential target genes of the 204 differential miRNAs identified, and a Venn diagram of the results was performed. Subsequently, the target genes of differential miRNAs were analyzed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis. Finally, to validate the miRNA microarray data, reverse transcription-quantitative PCR (RT-qPCR) was performed for 8 differentially expressed miRNAs (miR-193a-3p, miR-19a-3p, miR-19b-3p, miR-370-3p, miR-1275, miR-490-5p, miR-630 and miR-665) using DLBCL and LRH fresh samples. In total, 204 miRNAs exhibited differential expression, including 105 downregulated and 54 upregulated miRNAs. The cut-off criteria were set as P≤0.05 and fold-change ≥2. A total of 7,522 potential target genes for the 204 miRNAs were predicted. Potential target genes were enriched in the following pathways: 'Cancer', 'MAPK signaling pathway', 'regulation of actin cytoskeleton', 'focal adhesion', 'endocytosis', 'Wnt signaling pathway', 'axon guidance', 'calcium signaling pathway' and 'PI3K/AKT signaling pathway'. A total of 8 miRNAs were validated by RT-qPCR, and 4 miRNAs (miR-19b-3p, miR-193a-3p, miR-370-3p and miR-490-5p) exhibited low expression levels in DLBCL (P<0.05), while miR-630 was highly expressed in DLBCL (P<0.05). Overall, the present study screened 204 differentially expressed miRNAs and analyzed the expression levels of 8 differentially expressed miRNAs in DLBCL. These differentially expressed miRNAs may serve as therapeutic targets for improvement of therapeutic efficacy in DLBCL in the future.

Selection of mutant µplasmin for amyloid-ß cleavage in vivo.

One of the main culprits of Alzheimer's disease (AD) is the formation of toxic amyloid-ß (Aß) peptide polymers and the aggregation of Aß to form plaques in the brain. We have developed techniques to purify the catalytic domain of plasmin, micro-plasmin (µPlm), which can be used for an Aß-clearance based AD therapy. However, in serum, µPlm is irreversibly inhibited by its principal inhibitor α2-antiplasmin (α2-AP). In this study, we engineered and selected mutant forms of µPlm that are both catalytically active and insensitive to α2-AP inhibition. We identified surface residues of µPlm that might interact and bind α2-AP, and used an alanine-scanning mutagenesis method to select residues having higher activity but lower α2-AP inhibition. Then we employed saturation mutagenesis for further optimize both properties. Modeled complex structure of µPlm/α2-AP shows that F587 is a critical contact residue, which can be used as a starting position for further investigation.

Prognostic value of MYD88 L265P mutation in diffuse large B cell lymphoma via droplet digital PCR.

To assess the prevalence and prognostic value of myeloid differentiation factor 88 (MYD88) expression and mutational status in diffuse large B cell lymphoma (DLBCL), a total cohort of 100 patients with DLBCL were studied using immunohistochemistry (IHC) and droplet digital polymerase chain reaction (DDPCR), and the association between MYD88 expression and clinicopathological parameters was analyzed. Overall, the positive expression rate of MYD88 protein was 38% and the gene mutation rate was 29%. The positive expression and mutation rates were the highest in the primary central nervous system lymphomas (58.33 and 66.67%, respectively). The coincidence rate of the results of MYD88 expression between IHC and DDPCR results was 73% (73/100). Univariate survival analysis showed that age (≥60 years old), high neutrophil/lymphocyte count ratio, low lymphocyte count, c­Myc ≥40%, positive MYD88 protein expression, and gene mutation were associated with poorer prognosis rates. Multivariate survival analysis revealed that MYD88 expression was an independent prognostic factor affecting overall survival. In conclusion, the results of this study demonstrated that MYD88 mutation was a valuable index to evaluate the prognosis of DLBCL. DDPCR can be used as a method for detecting MYD88 mutations, although it was not completely consistent with the results of IHC.

TCL1 as a hub protein associated with the PI3K/AKT signaling pathway in diffuse large B-cell lymphoma based on proteomics methods.

This study aimed to investigate the hub protein related to the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in diffuse large B-cell lymphoma (DLBCL). We used proteomics methods (iTRAQ) to explore the differentially expressed proteins in the non-germinal center B-cell -like (non-GCB) DLBCL in our previous study. In this study, a total of 137 formalin-fixed paraffin-embedded DLBCL tissue samples were analyzed via immunohistochemistry to verify the expression of TCL1, AKT1 + 2+3, IKKß and to determine the differentially expressed proteins associated with the PI3K/AKT signaling pathway. Spearman correlation was used to analyze the relationship between these proteins, and survival analysis was used to investigate their effects on prognosis. Immunohistochemistry analysis indicated that TCL1, AKT1 + 2+3, and IKKß were highly positively expressed in DLBCL. Results showed that the expression of TCL1 was related to ethnicity (p = 0.022), primary site (p = 0.045), Ann Arbor stage (p = 0.037), the International Prognostic Index (p = 0.005), ß2-microglobulin (p = 0.030), BCL2 expression (p < 0.001), and Ki-67 expression (p = 0.008). A positive correlation was found between TCL1 and AKT1 + 2+3 (p < 0.001; r = 0.475). A positive correlation was also found between AKT1 + 2+3 and IKKß (p < 0.001; r = 0.342). In survival analysis, anemia, non-treatment with R­CHOP, positive TCL1 expression, and Ki-67 expression≥50% independently predicted short progression-free survival and overall survival in the total cohort (p < 0.05). Thus, TCL1 as a hub protein is associated with the PI3K/AKT signaling pathway in DLBCL. TCL1 expression indicated a poor prognosis in patients with DLBCL. With further studies, TCL1 may be established as a reliable prognostic biomarker and potential immunotherapeutic target for improving therapeutic efficacy for DLBCL in the future.

Clinicopathologic features and prognostic analysis of Waldeyer ring B-cell lymphoma.

This retrospective study is to explore the clinicopathologic, immunophenotypic, and molecular genetic features of Waldeyer ring B-cell lymphoma (WR-BCL).Tissue arrays from 65 WR-BCL cases were subjected to pathologic and immunophenotypic detections. Expression of Epstein-Barr virus-encoded small RNA (EBER) was detected by in situ hybridization. Interferon regulatory factor 4 (IRF4), BCL-2, BCL-6, and C-myelocytomatosis viral oncogeneav (MYC) gene abnormalities were investigated using interphase fluorescence in situ hybridization.Among the 65 patients, there were 12 nasopharynx cases, 49 tonsil cases, and 4 tongue root cases. Moreover, there were 49 cases of diffuse large BCL (DLBCL) and 16 cases of follicular lymphoma (FL). More than 60% of the patients had Ann Arbor stage III/IV disease, with infiltrated neighboring organs, invaded spleens, and increased lactate dehydrogenase (LDH) levels. Tumor cells were positive for multiple myeloma antigen 1 (MUM1), BCL-2, BCL-6, and C-MYC. EBER expression was detected in lymphoma cells of 2 cases. Alteration frequencies of IRF4, BCL-2, BCL-6, and C-MYC were 24.6%, 32.3%, 27.7%, and 30.7%, respectively. Approximately 67.69% cases had stages 0 to II disease, while 32.31% cases had stage III disease. Five-year overall survival rate was 65.12%. Eastern Cooperative Oncology Group performance status (ECOG) score ≥2 was the only adverse factor for overall survival. IRF4/MUM1, C-MYC, and CD10 expressions were related to poor disease prognosis. WR-BCLs were largely dependent on ECOG, LDH, and bone marrow involvement. WR-DLBCL was associated with poor survival outcomes compared with WR-FL.The WR-DLBCLs have distinct clinicopathologic features, with correlations between the IRF4/MUM1, C-MYC and CD10 expressions, ECOG, LDH, bone marrow involvement, and the disease prognosis.

Clinical significance of 'double-hit' and 'double-expression' lymphomas.

BACKGROUND: 'Double-hit' lymphoma (DHL) and 'double-expression' lymphoma (DEL) involving gene rearrangement and protein expression of MYC and BCL2/BCL6 have recently become the most commonly used terms to describe the poor prognostic types of diffuse large B-cell lymphoma (DLBCL). However, the clinical and pathological spectra of these rare entities have not been well defined. The aim of this study was to determine the frequency of DHL and DEL in DLBCL and their prognostic impacts in the era of cyclophosphamide, doxorubicin, vincristine and prednisone plus rituximab therapy. METHODS: The data and tissues from 98 patients diagnosed with DLBCL were used in this study. Formalin-fixed and paraffin-embedded tissues were constructed for immunohistochemistry (IHC) and interphase fluorescene in situ hybridisation (FISH) analysis for MYC, BCL6 and BCL2 rearrangements. RESULTS: There were 14 cases (14.29%, 14/98) and 34 cases (34.70%, 34/98) of lymphomas with the DHL and DEL of MYC and BCL2/BCL6, respectively. DLBCL patients with MYC/BCL2 rearrangements more frequently had bone marrow involvement (p=0.002), and their tumours were commonly of the germinal centre B cell (GCB) subtype. Patients with MYC+/BCL2 +coexpression were more often assessed using the International Prognostic Index (IPI), (Performance Status) PS score and bone marrow involvement. Patients with MYC+/BCL6 +coexpression were associated with their IPI values, Eastern Cooperative Oncology Group scores and occurrence of B symptoms. Their lymphomas were more often of the non-GCB subtype (p=0.010). Multivariate analysis showed that IPI, bone marrow involvement, rearrangements of BCL2, BCL6 and MYC, expression concurrent with rearrangements and coexpression were all significantly associated with overall survival and progression-free survival, with the exception of MYC+/BCL6 +coexpression. CONCLUSIONS: MYC/BCL2 DHL, MYC/BCL6 DHL and MYC/BCL2 DEL are an aggressive B cell lymphoma and patients have a poor prognosis. IPI and bone marrow involvement were independent prognostic factors for DHL and DEL. BCL2, BCL6 and MYC rearrangements translocation, expression concurrent rearrangements and coexpression were were independent prognostic factors for survival. POTENTIAL IMPLICATIONS: The present study analysed the genomic alterations and protein expression levels of MYC, BCL2 and BCL6 using FISH and IHC in Chinese patients with DLBCL.We assessed the frequency, clinicopathological features and the prognostic impacts of DHL and DEL in a cohort of de novo DLBCL patients and evaluated the role of each genetic translocation separately and in combination in order to provide reliable conclusions and practical recommendations for diagnostic workups and prognostic predictions.

Quantitative proteomics analysis of differentially expressed proteins in activated B-cell-like diffuse large B-cell lymphoma using quantitative proteomics.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with unclear pathogenesis. DLBCL accounts for 30%-35% of all non-Hodgkin lymphomas (NHLs) and is an aggressive subtype of mature B-cell neoplasm. At present, half of DLBCL cases can be cured, although one-third of patients experience recurrence after treatment and enter advanced tumor stage. This study aimed to investigate the differentially expressed proteins in activated B-cell-like-DLBCL (ABC-DLBCL) through quantitative proteomics (iTRAQ). Seven ABC-DLBCL experimental samples and eight control samples (reactive hyperplasia of the lymph node) were obtained from fresh tissues. The exclusion criteria were expressed as follows: (1) patients with other lymphoid diseases; and (2) patients undergoing chemical treatment. A total of 5974 proteins were identified. P value < 0.05 and multiple expressions were more than 1.2-fold. A total of 131 upregulated and 204 downregulated differentially expressed proteins were identified. Gene ontology (GO) and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway analysis were performed. Protein-protein interaction (PPI) network analysis was conducted. The expression levels of HSP90AB1, GNA13, LAMB2, LAMA5, YWHAZ, and IKBKB were evaluated through PRM and TCGA to validate the accuracy of iTRAQ and liquid chromatography-tandem mass spectrometry results. Results of differential multiple and t-test showed differences in the expression levels of six target proteins between the control and experimental groups. To the best of our knowledge, the present study is the first to identify proteins associated with ABC-DLBCL using iTRAQ technology. Our results provide new insights into the pathogenesis of ABC-DLBCL. The combination of ABC-DLBCL-associated signaling pathway proteins and targeted therapy to reverse drug resistance is of great significance in improving the comprehensive treatment of lymphoma and reducing mortality of affected individuals. The feasibility of the present study is limited due to the number of samples, and future studies are required to determine the function of proteins in ABC-DLBCL development.

Anti-quorum Sensing Activities of Selected Coral Symbiotic Bacterial Extracts From the South China Sea.

The worldwide increase in antibiotic-resistant pathogens means that identification of alternative antibacterial drug targets and the subsequent development of new treatment strategies are urgently required. One such new target is the quorum sensing (QS) system. Coral microbial consortia harbor an enormous diversity of microbes, and are thus rich sources for isolating novel bioactive and pharmacologically valuable natural products. However, to date, the versatility of their bioactive compounds has not been broadly explored. In this study, about two hundred bacterial colonies were isolated from a coral species (Pocillopora damicornis) and screened for their ability to inhibit QS using the bioreporter strain Chromobacterium violaceum ATCC 12472. Approximately 15% (30 isolates) exhibited anti-QS activity, against the indicator strain. Among them, a typical Gram-positive bacterium, D11 (Staphylococcus hominis) was identified and its anti-QS activity was investigated. Confocal microscopy observations showed that the bacterial extract inhibited the biofilm formation of clinical isolates of wild-type P. aeruginosa PAO1 in a dose-dependent pattern. Chromatographic separation led to the isolation of a potent QS inhibitor that was identified by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) spectroscopy as DL-homocysteine thiolactone. Gene expression analyses using RT-PCR showed that strain D11 led to a significant down-regulation of QS regulatory genes (lasI, lasR, rhlI, and rhlR), as well as a virulence-related gene (lasB). From the chemical structure, the target compound (DL-homocysteine thiolactone) is an analog of the acyl-homoserine lactones (AHLs), and we presume that DL-homocysteine thiolactone outcompetes AHL in occupying the receptor and thereby inhibiting QS. Whole-genome sequence analysis of S. hominis D11 revealed the presence of predicted genes involved in the biosynthesis of homocysteine thiolactone. This study indicates that coral microbes are a resource bank for developing QS inhibitors and they will facilitate the discovery of new biotechnologically relevant compounds that could be used instead of traditional antibiotics.

PIK3CA amplification and PTEN loss in diffused large B-cell lymphoma.

Although it has been known that PIK3CA was amplified and PTEN was deficient on protein level in DLBCL, the clinicopathological significance of PIK3CA and PTEN genetic change on DNA level hasn't been established. Here, in our present study, to understand the clinical significance of genetic status of PIK3CA and PTEN in DLBCL, fluorescent in-situ hybridization (FISH) was employed to evaluate the genetic change of PIK3CA and PTEN in clinical sample tissues consist of 205 cases. Incidentally, to understand the clinicopathological significance of genetic change of PIK3CA and PTEN, Cross-table analysis was used to analyze the association between genetic change of PIK3CA and PTEN versus clinicopathological variables available to us, including age, gender, size, location, international prognosis index, performance state, B-symptom, clinical stage, Extra nodal site, concentration of lactate dehydrogenase, therapeutic effects, treatment and overall prognosis. It was found that PIK3CA was amplified and PTEN was deficient on DNA level, the percentage of amplification and loss was 12.7% (26/205) and 12.2% (25/205), respectively. Additionally, no significant association was observed between genetic change of PIK3CA and PTEN versus clinicopathological variables available. Nor was the significant correlation found between loss of PTEN versus PIK3CA amplification. Our results suggest that PTEN deficiency and amplification of PIK3CA on DNA level was an event in the pathogenesis of DLBCL.

Fungal community dynamics during a marine dinoflagellate (Noctiluca scintillans) bloom.

Contamination and eutrophication have caused serious ecological events (such as algal bloom) in coastal area. During this ecological process, microbial community structure is critical for algal bloom succession. The diversity and composition of bacteria and archaea communities in algal blooms have been widely investigated; however, those of fungi are poorly understood. To fill this gap, we used pyrosequencing and correlation approaches to assess fungal patterns and associations during a dinoflagellate (Noctiluca scintillans) bloom. Phylum level fungal types were predominated by Ascomycota, Chytridiomycota, Mucoromycotina, and Basidiomycota. At the genus level drastic changes were observed with Hysteropatella, Malassezia and Saitoella dominating during the initial bloom stage, while Malassezia was most abundant (>50%) during onset and peak-bloom stages. Saitoella and Lipomyces gradually became more abundant and, in the decline stage, contributed almost 70% of sequences. In the terminal stage of the bloom, Rozella increased rapidly to a maximum of 50-60%. Fungal population structure was significantly influenced by temperature and substrate (N and P) availability (P < 0.05). Inter-specific network analyses demonstrated that Rozella and Saitoella fungi strongly impacted the ecological trajectory of N. scintillans. The functional prediction show that symbiotrophic fungi was dominated in the onset stage; saprotroph type was the primary member present during the exponential growth period; whereas pathogentroph type fungi enriched in decline phase. Overall, fungal communities and functions correlated significantly with N. scintillans processes, suggesting that they may regulate dinoflagellate bloom fates. Our results will facilitate deeper understanding of the ecological importance of marine fungi and their roles in algal bloom formation and collapse.

Association between clinicopathological features and survival in patients with primary and paired metastatic colorectal cancer and KRAS mutation.

The KRAS gene mutation is involved in several types of tumors. However, the potential role of the KRAS mutation in human primary and paired metastatic colorectal cancer (CRC) among different nationalities is poorly understood. In the present study, we assessed the relationship between KRAS mutation status and overall survival (OS) and disease-free survival (DFS) in 230 patients with primary and paired metastatic CRC. The KRAS mutation rate in primary CRC tissue was 43.0% (99/230), which was higher than in paired metastatic CRC, which was 31.9% (23/72; P<0.001). Clinicopathologically, the KRAS gene mutation rate was higher in tumors that had infiltrated more deeply (T3, T4) and in lymph node (LN) metastases (N1/N2) (P=0.029 and P=0.010, respectively). The KRAS gene status did not differ between the Han and Uyghur nationalities in both primary and metastatic CRC. In 72 paired cases, the KRAS mutation rate in primary CRC was significantly higher than in metastatic CRC (P<0.001) and in metastatic CRC that had infiltrated more deeply (T3, T4) (P=0.034). In the metastatic cases, the KRAS gene mutation rate was higher in patients aged over 65 years (P=0.035). Specifically, KRAS mutation was correlated with a poorer OS and DFS (P=0.004 and P=0.029, respectively). In our study, 35 patients with wild-type KRAS who received cetuximab targeted therapy had a better DFS than patients with mutant KRAS (P=0.029). The results of the current study demonstrate that the KRAS status is significantly associated with infiltrating LN metastases and the TNM stage in primary CRC. In addition, the results show that the KRAS mutation is significantly more common in primary tumors than in paired metastatic CRC, and the KRAS mutation is correlated with a shorter OS and DFS, as patients with wild-type KRAS who received cetuximab experienced a longer DFS.

Clinicopathological significance of miR-101-3p and c-myc mRNA expression in diffused large B-cell lymphoma.

MiR-101-3p has been suggested to be implicated in the pathogenesis of lymphoma, however little is known regarding clinicopathological significance of its expression in diffused large B-cell lymphoma (DLBCL). In contrast, although c-myc has been extensively studied in DLBCL, no direct evidence concerning clinicopathological significance has been well established, either. Given this, in our present study, to understand the significance of both miR-101-3p and c-myc expression on mRNA level in DLBCL, real-time quantitative PCR was used to detect the expression of miR-101-3p and c-myc on mRNA level in 100 cases of DLBCL samples. Association between expression of miR-101-3p and c-myc and clinicopathological variables available was statistically analyzed using Cross-Table test. It was shown that only significant association was observed between miR-101-3p expression and histopathological subtype and therapeutic regimen, no significant relationship was found with other clinicopathological variables. As for c-myc expression, only significant association was found with gender, IPI, and activity of LDH in serum; No significant relations were found with other clinicopathological variables. Together, our study presents the direct evidence regarding clinicopathological significance of miR-101-3p and c-myc expression in DLBCL, which warrants further confirmation in different cohorts with larger sample sizes.

Profile of Citrobacter freundii ST2, a Multi-acyl-homoserine Lactone Producer Associated with Marine Dinoflagellates.

Marine algae provide a unique niche termed the phycosphere for microorganism inhabitation. The phycosphere environment is an important niche for mutualistic and competitive interactions between algae and bacteria. Quorum sensing (QS) serves as a gene regulatory system in the microbial biosphere that allows bacteria to sense the population density with signaling molecules, such as acyl-homoserine lactone (AHL), and adapt their physiological activities to their surroundings. Understanding the QS system is important to elucidate the interactions between algal-associated microbial communities in the phycosphere condition. In this study, we isolated an epidermal bacterium (ST2) from the marine dinoflagellate Scrippsiella trochoidea and evaluated its AHL production profile. Strain ST2 was classified as a member of the genus Citrobacter closely related to Citrobacter freundii by 16S rRNA gene sequence analysis. Thin-layer chromatography revealed that C. freundii ST2 secreted three active AHL compounds into the culture supernatant. Specific compounds, such as N-butyryl-L-homoserine lactone (C4-AHL), N-octanoyl-DL-homoserine lactone (C8-AHL), and N-decanoyl-DL-homoserine lactone (C10-AHL), were identified by high-resolution tandem mass spectrometry. Carbon metabolic profiling with Biolog EcoPlate™ indicated that C. freundii ST2 was widely used as a carbon source and preferred carbohydrates, amino acids, and carboxylic acids as carbon substrates. Our results demonstrated that C. freundii ST2 is a multi-AHL producer that participates in the phycosphere carbon cycle.

Genome sequence of Enterobacter sp. ST3, a quorum sensing bacterium associated with marine dinoflagellate.

Phycosphere environment is a typical marine niche, harbor diverse populations of microorganisms, which are thought to play a critical role in algae host and influence mutualistic and competitive interactions. Understanding quorum sensing-based acyl-homoserine lactone (AHL) language may shed light on the interaction between algal-associated microbial communities in the native environment. In this work, we isolated an epidermal bacterium (was tentatively named Enterobacter sp. ST3, and deposited in SOA China, the number is MCCC1K02277-ST3) from the marine dinoflagellate Scrippsiella trochoidea, and found it has the ability to produce short-chain AHL signal. In order to better understand its communication information at molecular level, the genomic map was investigated. The genome size was determined to be 4.81 Mb with a G + C content of 55.59%, comprising 6 scaffolds of 75 contigs containing 4647 protein-coding genes. The functional proteins were predicted, and 3534 proteins were assigned to COG functional categories. An AHL-relating gene, LuxR, was found in upstream position at contig 1. This genome data may provide clues to increase understanding of the chemical characterization and ecological behavior of strain ST3 in the phycosphere microenvironment.

Genome Sequence Analysis Reveals Evidence of Quorum-Sensing Genes Present in Aeromonas hydrophila strain KOR1, Isolated from a Mangrove Plant (Kandelia obovata).

Aeromonas hydrophila strain KOR1, isolated from mangrove rhizosphere soil, has the ability to produce the quorum-sensing signal molecule. Here, we report the 4.78-Mb genome sequence of strain KOR1, and found its quorum-sensing encoding gene LuxR. The data will be crucial to understanding the quorum-sensing-dependent phenotypes of this bacterium.