MicroRNA-34c-5p provokes isoprenaline-induced cardiac hypertrophy by modulating autophagy via targeting ATG4B

Pathological cardiac hypertrophy serves as a significant foundation for cardiac dysfunction and heart failure. Recently, growing evidence has revealed that microRNAs (miRNAs) play multiple roles in biological processes and participate in cardiovascular diseases. In the present research, we investigate the impact of miRNA-34c-5p on cardiac hypertrophy and the mechanism involved. The expression of miR-34c-5p was proved to be elevated in heart tissues from isoprenaline (ISO)-infused mice. ISO also promoted miR-34c-5p level in primary cultures of neonatal rat cardiomyocytes (NRCMs). Transfection with miR-34c-5p mimic enhanced cell surface area and expression levels of foetal-type genes atrial natriuretic factor (Anf) and β-myosin heavy chain (β-Mhc) in NRCMs. In contrast, treatment with miR-34c-5p inhibitor attenuated ISO-induced hypertrophic responses. Enforced expression of miR-34c-5p by tail intravenous injection of its agomir led to cardiac dysfunction and hypertrophy in mice, whereas inhibiting miR-34c-5p by specific antagomir could protect the animals against ISO-triggered hypertrophic abnormalities. Mechanistically, miR-34c-5p suppressed autophagic flux in cardiomyocytes, which contributed to the development of hypertrophy. Furthermore, the autophagy-related gene 4B (ATG4B) was identified as a direct target of miR-34c-5p, and miR-34c-5p was certified to interact with 3' untranslated region of Atg4b mRNA by dual-luciferase reporter assay. miR-34c-5p reduced the expression of ATG4B, thereby resulting in decreased autophagy activity and induction of hypertrophy. Inhibition of miR-34c-5p abolished the detrimental effects of ISO by restoring ATG4B and increasing autophagy. In conclusion, our findings illuminate that miR-34c-5p participates in ISO-induced cardiac hypertrophy, at least partly through suppressing ATG4B and autophagy. It suggests that regulation of miR-34c-5p may offer a new way for handling hypertrophy-related cardiac dysfunction.

Potentiating CD8

Metabolic regulation has been proven to play a critical role in T cell antitumor immunity. However, cholesterol metabolism as a key component of this regulation remains largely unexplored. Herein, we found that the low-density lipoprotein receptor (LDLR), which has been previously identified as a transporter for cholesterol, plays a pivotal role in regulating CD8

From SARS to COVID-19: pathogens, receptor, pathogenesis and principles of the treatment / 中华病理学杂志

COVID-19 is an infectious disease caused by 2019-nCoV and characterizes as an atypical pneumonia. Since 2019-nCoV is a newly emerging virus, the pathogenesis of COVID-19 is not well known. Most patients had a self-limited course, and some became severe even death. In this review, the authors compared two coronavirus outbreaks during the past two decades: the SARS-CoV and 2019-nCoV. Among the biological nature of the pathogens, viral receptor distribution on the human cells, and the pathological findings in the targeted organs and clinical features of the patients with the diseases, found similarities and differences between the two diseases. Due to the shared receptor ACE2 and the pathological similarities of the SARS-CoV and 2019-nCoV diseases. They proposed a pathogenesis model for COVID-19. Like the SARS-CoV disease, COVID-19 is a systematic disease and targets the lungs, vasculatures, and the immune system. The basic pathogenesis involves two interlinked processes: a severe lung inflammation and immune deficiency, both of which are related to an inappropriate immune response and over-production of cytokines. Thus, treatment approaches should include antiviral and anti-proinflammatory cytokines, anti-infectious and life support therapies, especially in patients with severe diseases.

FBX8 degrades GSTP1 through ubiquitination to suppress colorectal cancer progression.

F-box only protein 8 (FBX8), as a critical component of the SKP1-CUL1-F-box (SCF) E3 ubiquitin ligases, has been associated with several malignancies through interacting with a member of proteins. However, the substrates of FBX8 for destruction in the progression of colorectal carcinoma (CRC) need to be explored. Here, we show that loss of FBX8 accelerates chemical-induced colon tumorigenesis. FBX8 directly targets GSTP1 for ubiquitin-mediated proteasome degradation in CRC. GSTP1 promotes the proliferation, invasion, and metastasis of CRC cells. Furthermore, GSTP1 is upregulated in CRC tissue samples and predicts poor prognosis of CRC patients. The inactivation of FBX8 negatively correlated with increased levels and stability of GSTP1 in clinical CRC tissues and FBX8 knockout transgenic mice. These findings identify a novel ubiquitination pathway as FBX8-GSTP1 axis that regulates the progression of CRC, which might be a potential prognostic biomarker for CRC patients.

Culture and identification of tumor stem cells from surgically resected colorectal cancer tissues / 南方医科大学学报

OBJECTIVE@#To obtain cancer stem cells (CSCs) from surgically resected colorectal cancer specimens and identify their stem cell characteristics.@*METHODS@#Colorectal cancer tissue specimen obtained from a patient undergoing radical resection of colorectal cancer were implanted in nude mice, and the xenograft was harvested 1 month later to obtain purified tumor cells by enzyme digestion and adherent culture. The CSCs were screened by limiting dilution method and serum-free culture to identify their phenotypes. Soft agar colony assay was used to assess the proliferative ability of the CSCs and human colorectal cancer cell line SW480. The tumorigenic ability of the isolated CSCs and SW480 cells was evaluated by observing their subcutaneous tumor formation in nude mice. Western blotting and immunofluorescence assay were used to detect the immunophenotype of the CSCs and SW480 cells.@*RESULTS@#The primary cultured CSCs from clinical specimens of colorectal cancer underwent differentiation in the presence of serum in the culture. Soft agar colony formation assay showed that the CSCs had a colony formation rate above 50%, significantly higher than the rate of colorectal cancer SW480 cells (4.41%; < 0.01). In nude mice, subcutaneous injection of 500 CSCs was sufficient to result in subcutaneous tumor formation, while the injection of 500 SW480 cells failed to form any subcutaneous tumors. The CSCs expressed CD133 and CD44 but not CK7, while SW480 cells expressed CK7 but not CD133 or CD44.@*CONCLUSIONS@#CSCs can be derived by primary culture of cancer cells obtained from surgically resected colorectal cancer tissue followed by serum-free culture, and the CSCs obtained have self-renewal and differentiation abilities.

Liver protection of crocetin against paraquat poisoning in rats / 中华危重病急救医学

Objective To study the liver protection of crocetin against paraquat (PQ) poisoning induced acute liver injury in rats. Methods Fifty-four male Wistar rats were randomly divided into control group, exposure group and treatment group, and the rats in each group were subdivided into the 0.5th, 2nd, and 6th day after exposure subgroups (n = 6). The model of acute liver failure induced by PQ poisoning was reproduced by intraperitoneal injection of 20 mg/kg of 20% PQ, and the rats in control group was injected with the same amount of normal saline. The rats in treatment group were given with intraperitoneal injection of 50 mg/kg crocetin after 0.5 day, once a day until they were sacrificed; the other two groups were injected with the same amount of normal saline. The rats in all groups were sacrificed at the corresponding time points, and blood was collected from inferior vena cava and hepatic tissue was harvested. Hematoxylin and eosin (HE) staining was used to observe the pathological changes in liver tissue on the 6th day under light microscope. Enzyme linked immunosorbent assay (ELISA) was used to detect the serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA expressions of inducible nitric oxide synthase (iNOS) and nuclear factor-κB (NF-κB). The activities of apoptosis related factors, including caspase-8, -9, -12, in hepatic tissue were determined on the 6th day with chromogenic substrate method. Results In the liver tissue of exposed group, extensive infiltration of the inflammatory cells and the diffuse fragments necrosis were visible, and the regeneration of the liver cells was not obvious, and severity of the injury in a time dependent way. In the treatment group, the structure of hepatic artery was visible, and the infiltration of necrosis, congestion and inflammatory cells were not obvious. On the 0.5th, 2nd, and 6th day, serum levels of IL-6 and TNF-α, the mRNA expressions of iNOS and NF-κB in liver tissue, and the caspase-8, -9, -12 activities on the 6th day in the exposure group and treatment group were significantly higher than those in the control group. And the parameters in treatment group were significantly lower than those of the exposure group [IL-6 (ng/L): 188.37±64.21 vs. 376.61±82.42 on the 0.5th day, 287.18±58.69 vs. 432.77±96.28 on the 2nd day, 234.24±10.17 vs. 375.41±37.59 on the 6th day; TNF-α (ng/L): 472.36±76.43 vs. 688.33±102.19 on the 0.5th day, 189.32±87.54 vs. 296.21±89.77 on the 2nd day, 99.28±16.13 vs. 168.41±66.78 on the 6th day; iNOS mRNA (gray value): 2.998±0.801 vs. 3.453±0.026 on the 0.5th day, 3.126±0.306 vs. 5.259±0.153 on the 2nd day, 0.841±0.135 vs. 1.225±0.057 on the 6th day; NF-κB mRNA (gray value): 1.569±0.818 vs. 2.361±0.063 on the 0.5th day, 2.345±0.489 vs. 4.668±0.368 on the 2nd day, 2.348±0.316 vs. 3.972±0.449 on the 6th day; caspase-8 (pmol/mg): 126.77±9.97 vs. 199.18±66.48 on the 6th day; caspase-9 (pmol/mg): 213.12±69.06 vs. 321.62±89.39 on the 6th day; caspase-12 (pmol/mg): 183.46±70.52 vs. 219.68±53.93 on the 6th day, all P < 0.05]. Conclusion Crocetin has protective effect on liver in rats with PQ poisoning, which role is related with reducing the blood level of inflammatory factors, inhibiting the hepatic caspase-8, -9, -12 activities and gene expressions of iNOS and NF-κB.

Screening of Tiam1-related genes contributing to metastasis of colorectal cancer using a gene expression profiling chip / 临床与实验病理学杂志

Purpose To screen and identify T cell lymphoma invasion and metastasis 1 (Tiam1) related genes and expression profile during distant metastasis of colorectal cancer. Methods Colorectal cancer( CRC) in a mice model was established by intraperitoneal injection of dimethylhydrazine ( DMH) . Five panels of fresh primary tumor tissues from Tiam1 transgenic mice were collected and com-pared with that from wild type mice. Differentially expressed genes were detected by Affymetrix human genome-wide expression profile chip and verified by real-time quantitative PCR ( qRT-PCR) analysis. Results The genechip result showed that 794 genes were differ-entially expressed by at least 3 folds in Tiam1 transgenic mice with distant metastasis of colorectal cancer tissue, including 400 up-regu-lated and 394 down-regulated ones. Bioinformatics analysis and gene co-expression network building identified 3 genes (PIK3R5, FIGF and RPS6KA6) with specific expression in colorectal cancer tissue with distant metastasis, and this result was confirmed by qRT-PCR. Conclusion A specific Tiam1 gene expression profile related to colorectal cancer distant metastasis has been established through screening and identifying the genes related to Tiam1 by gene chip technique. These findings provide a basis for exploring the molecular markers of colorectal cancer with distant metastasis.

Establishment of a colorectal cancer SW620 cell line stably over-expressing Wilm's tumor on X chromosome using a recombinant lentivirus vector / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a recombinant lentivirus vector for Wilm's tumor on X chromosome (WTX) gene and establish a colorectal cancer SW620 cell line with stable WTX over-expression.</p><p><b>METHODS</b>The full length coding region of WTX gene was amplified with PCR, and the amplified fragment was cloned into the lentivirus vector GV387. The recombinant lentivirus vector was transfected in 293T cells for packaging the virus, which was then transfected into colorectal cancer SW620 cells. The stably transfected cells were selected with G418, and the cellular expressions of WTX mRNA and protein were detected using quantitative PCR and Western blotting.</p><p><b>RESULTS</b>The recombinant plasmid was successfully constructed as verified by sequence analysis. Quantitative PCR and Western blotting results showed that trasnfection with the recombinant lentivirus significantly increased the expression levels of WTX in SW620 cells.</p><p><b>CONCLUSION</b>We successfully established a colorectal cancer cell lines with stable over-expression of WTX, which provides an essential cell model for studying the role of WTX in the tumorigenesis and progression of colorectal cancer.</p>

Prognostic value of syndecan binding protein in colorectal carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the clinical significance of syndecan binding protein (SDCBP) expression in human colorectal carcinoma (CRC) and its value in predicting the postoperative survival of the patients.</p><p><b>METHODS</b>The follow-up data for 10 years were collected from 109 primary CRC patients with immunohistochemical data of SDCBP expression in the tumor tissues. The relationship between SDCBP expression and the clinical factors was analyzed, and survival analysis was performed using the Kaplan-Meier and Cox regression analysis models.</p><p><b>RESULTS</b>SDCBP expression in CRC was significantly associated with the postoperative survival time (χ(2)=8.336, P=0.004) and lymph node metastasis (P=0.001) of the patients, but not with age, gender, depth of invasion, tissue differentiation or histological type of the tumor. Kaplan-Meier survival curves showed that the patients expression high levels of SDCBP in the CRC tissues had a significantly shorter postoperative mean survival time and a lower 7-year survival rate than those with low SDCBP expressions [52.300∓6.508 vs 86.184∓5.358 months, (38.6∓6.4)% vs (61.5∓6.7)%; χ(2)=10.585, P=0.001]. Multivariate Cox analysis revealed that a high expression of SDCBP (B=0.605, P=0.034) and lymph node metastasis (B=0.677, P=0.013) were the main factors related to death in CRC patients.</p><p><b>CONCLUSION</b>SDCBP expression level can serve as an indicator for lymph node metastasis, TNM staging, and outcome prediction of CRC.</p>

Inhibitory effect of miRNA-143 on the invasiveness of cervical can-cer cells by targeting MACC1 / 中国肿瘤临床

Objective:To illustrate the role of miRNA-143 on the invasiveness of cervical cancer cells. Methods:MiRNA-143 mimics or inhibitor sequences were transiently expressed in the cervical cancer cells by liposome transfection. Transwell assay was ap-plied to test the invasive ability of cervical cancer cells after miRNA-143 over-expression or inhibition. Bioinformatics assay was used to predict the targets of miRNA-143. RT-qPCR and luciferase reporter assay were performed to detect the expression of MACC1 mRNA in the cancer cells. RT-qPCR was conducted to test the expression of miRNA-143 and MACC1 mRNA in 20 fresh primary cervi-cal cancer and their matched para-neoplastic tissues. Statistical analyses were performed to evaluate the association between the expres-sion of miRNA-143 and MACC1 mRNA in the 20 cases of cervical cancer. Results:Transwell assays revealed that the miRNA-143 over-expression inhibited the cell invasiveness, while miRNA-143 inhibition promoted the invasive ability of the cervical cancer cells. Bioinformatics analyses revealed that miRNA-143 could target the 3'-UTR of MACC1. Dual luciferase reporter assay confirmed that miRNA-143 can affect 3'-UTR sequence in MACC1 genes. RT-qPCR analyses indicated that the expression of MACC1 mRNA was ob-viously down-regulated after miRNA-143 over-expression, while significantly increased after the miRNA-143 inhibition. The migration in Caski/miRNA-143 inhibitor cells was obviously elevated after being transfected with MACC1 shRNAs. RT-qPCR analyses showed that the expression of miRNA-143 was obviously decreased in the cancer tissues compared with the normal tissues, while MACC1 mRNA was apparently decreased in cancer tissues compared with the normal ones. Statistical analyses revealed that miRNA-143 was negatively correlated with MACC1 mRNA in the 20 cases of cervical cancer. Conclusion:This study reveals that miRNA-143 is down-regulated in the cervical cancer tissues. MiRNA-143 may play an important role in the regulation of cell invasiveness by targeting MACC1 in the cervical cancer cells.

The function of miR-30b in colorectal cancer metastasis / 中国肿瘤临床

Objective:To determine the function of miR-30b in the metastasis of colorectal cancer cells. Methods:RT-qPCR was performed to test miR-30b expression in 20 fresh primary colorectal cancer tissues and their corresponding adjacent tissues. Transwell and wound healing assays were performed to test the invasion and migration of colorectal cancer cells after miR-30b overexpression or inhibition. Bioinformatics assay was performed to predict miR-30b targets. Western Blot and Dual Luciferase reporter assay were per-formed to test the expressions of Snail and downstream target genes in colorectal cancer cells. Results:The results reveal that miR-30b expression decreased in cancer tissues compared with normal tissues. Transwell and wound healing assays reveal that miR-30b overex-pression inhibited cell invasion and migration, whereas miR-30b inhibition promoted the invasion and migration of colorectal cancer cells. Bioinformatics analyses reveal that miR-30b targets the 3'-UTR of Snail. Dual Luciferase reporter assay confirms that miR-30b af-fects the 3'-UTR of Snail. Western Blot analyses show that Snail and Vimentin expressions were significantly downregulated, whereas E-cadherin expression obviously increased after miR-30b overexpression. However, Snail and Vimentin expressions increased, but E-cadherin expression decreased after miR-30b inhibition. Conclusion:The miR-30b gene is downregulated in colorectal cancer tis-sues. The miR-30b protein may be important in the regulation of cell invasion and migration by targeting Snail in colorectal cancer cells.

Effects of Tiam1 overexpression on biological characters of human colorectal cancer cells / 实用医学杂志

Objective To explore the effect of Tiam1 overexpression on the biological behaviors of human colorectal cancer cells ( CRC ) . Methods The human CRC lines under the established stable overexpression of Tiam1 were studied. Cell morphology was detected before and after transfection by commassie blue staining and scanning electron microscope. The proliferation in vitro of CRC was tested by cell cycle, MTT and plate colony formation assay, the migration and invasion ability of CRC was tested by Transwell assay. The proliferation ability in vivo was studied by induced subcutaneous tumors of nude mice. Results Compared with HT29/mock cells, HT29/Tiam1 cells formed as spindle, the pseudopodia increased and elongated. The proportion in S phase of HT29/Tiam1 was higher (t=19.546, P=0.000), the proliferation ability enhanced (F=177.125, P=0.000), colonies formation ratio increased ( t = 3 . 222 , P = 0 . 032 ) . The number of HT29/Tiam1 cells acrossing the microporous membrane (t = 4.832, P=0.001)and Matrigel(t=3.779, P = 0.005)all raised. On the fifteenth day, the growth deference between the HT29/Tiam1cells and HT29/mock cells in nude mice in vivo occurred. Till the thirtieth day, the size of the tumors in HT29/Tiam1 cell group were 2.3 times as large as that in HT29/mock cell group (F=53.040, P=0.002). Conclusions Tiam1 stable overexpression can promote the proliferation, migration and invasion ability of CRC which indicates its important role in carcinogenesis and evolution of colorectal cancer. Tiam1 may represent a new therapeutic target for colorectal cancer.

Expression of hMLH1 and hMSH2 in suspected hereditary non-polyposis colorectal cancer / 实用医学杂志

Objective To analyse the suspected hereditary non-polyposis colorectal cancer (HNPCC) in mismatch repair protein (MMR) expression of hMLH1 and hMSH2. Methods Immunohistochemical staining method was used for the detection of hMLH1 and hMSH2 protein expression in 193 cases suspected HNPCC patients, the deletion of MMR proteins was identified as highly suspected HNPCC cases. Results Of the 193 patients with suspected HNPCC hMLH1/hMSH2 abnormal expression rate was 29.02%; ≤30 years old was 40%, 31 ~ 40 years old was 28.05%, 41 ~ 50 years old was 28.71%,3 suspected HNPCC showed the deletion of hMLH1/hMSH2 protein expression at the same time ,; In the right colon , the left half colon and rectal anomaly detection rates were 40.74%, 32.65%and 18.89%; hMLH1/hMSH2 deletion was 46.15%with family history. Conclusions The deletion of MMR protein is closely related to age,site and family history in suspected HNPCC, and the deletion of hMLH1 is an important factor to induce early-set colorectal cancer. The deletion of hMLH1/hMSH2 at the same time indicates that hMLH1/hMSH2 genes may play important role in the incidence of HNPCC.

Comparison of telomerase, p53 and Ki-67 expression on colorectal serrated adenoma, traditional adenoma and colorectal cancer / 中国癌症杂志

Background and purpose:Colorectal serrated adenoma (SA) was ofifcially named in 2000 by the WHO as a separate disease, with unique properties compared with traditional adenoma (TA), and its relationship with colorectal cancer (CRC) is very concerned. This study was to analyze and compare the telomerase, p53 and Ki-67 immunohistochemical expression on the tissues of SA, TA and CRC. Methods:Immunohistochemistry was adopted to analyze the expression of telomerase, p53, and Ki-67 in 37 cases of SA, 36 cases of TA and 34 cases of CRC. Results:The p53-positive percentage of SA was signiifcantly lower than that of TA (P<0.01), and the p53-positive percentage of TA was signiifcantly lower than that of CRC (P<0.01). No signiifcant difference of Ki-67 expression was found between SA and TA, and the Ki-67-positive percentage of SA and TA was lower than that of CRC (P<0.01). The telomerase-positive percentage of TA was signiifcantly lower than that of SA (P<0.01), and the telomerase-positive percentage of SA was signiifcantly lower than that of CRC (P<0.05). Conclusion:Telomerase, P53, and Ki-67 immunohisto chemical analysis indicated that SA is a kind of proliferative adenoma, and telomerase activation may play a role in the cancer process.

Promoter methylation of Wilms' tumor gene on the X- chromosome in gastric cancer / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in methylation levels of the promoters of the tumor suppressor gene Wilms' tumor gene on the X-chromosome (WTX) and its possible role in gastric cancer.</p><p><b>METHODS</b>WTX promoter methylation levels were detected in 20 pairs of specimens of gastric cancer and matched normal tissues and in 3 gastric cancer cell lines (MGC803, SCG7901, and BGC823) using the Sequenom MassARRAY quantitative analysis system. The gastric cancer cell line BGC823 was treated with 5-aza-2'-deoxycytidine (5-aza-dC) for demethylation and the changes in the level of WTX promoter methylation were investigated.</p><p><b>RESULTS</b>WTX promoter methylation levels were very low and showed no significant differences among normal gastric tissues, gastric cancer tissues and the 3 gastric cancer cell lines. In BGC823 cells, treatment with 5-aza-dC did not obviously affect the promoter methylation levels of WTX.</p><p><b>CONCLUSION</b>High methylation levels of WTX promoters are rare in gastric cancer.</p>

Follicular immunoblastic lymphoma: a clinicopathologic and immunohistochemical study of a case / 南方医科大学学报

Primary follicular immunoblastic lymphoma (FIBL) is an extremely rare lymphoma. The positive expression of CD10 suggests the lymphoma originating from germinal centers (GC) and CD138-positive expression generally indicates plasmablastic or plasmacytic differentiation. We report such a rare case in a Chinese female patient and analyze the clinicopathologic and immunohistochemical features of this disease. PET-CT examination was performed to detect signs of systemic lymph node metastasis. We also discussed the differential diagnosis of FIBL from follicular lymphoma (FL) and reactive follicular hyperplasia (RFH). As a rare variant of human follicular lymphoma, FIBL is featured by a neoplastic overgrowth of intrafollicular immunoblasts. Compared with FL, FIBL has a greater chance to evolve into diffuse large B-cell lymphoma with therefore a poorer prognosis.

Expression of Dickkopf-1 in human colon carcinoma cell lines / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression of Dickkopf-1(DKK1) in 6 different colon carcinoma cell lines.</p><p><b>METHODS</b>The expression of DKK1 protein were detected in SW480, SW620, HT29, LS174T, LOVO, and HCT116 cells lines using Western blot analysis and immunocytochemistry, and the mRNA levels of DKK1 was detected using quantitative real-time PCR (qPCR).</p><p><b>RESULTS</b>The results of qPCR showed significantly higher expressions of DKK1 mRNA in HT29 and HCT116 cells than in the other 4 cells (P<0.05). Western blotting demonstrated that DKK1 was over-expressed in HCT116 and HT29 cells compared with that in the other cell lines. All the 6 cell lines were found to have positive DKK1 expression by immunocytochemical staining.</p><p><b>CONCLUSION</b>DKK1 shows differential expression patterns among the 6 human colon carcinoma cell lines.</p>

IDH mutations predict longer survival and response to temozolomide in secondary glioblastoma.

Recent studies have shown that isocitrate dehydrogenase 1/2 (IDH1/2) mutations occur frequently in secondary glioblastoma. This study aimed to investigate their impact on temozolomide chemosensitivity and relationship with O(6)-methylguanine DNA methyltransferase (MGMT) promoter methylation in secondary glioblastoma. Searches for IDH1 and IDH2 mutations, 1p19q codeletion, MGMT promoter methylation, and p53 expression were carried out in a series of 86 secondary glioblastomas and correlated with progression-free survival and overall survival. Response to temozolomide was evaluated by progression-free survival, as well as by tumor size on successive MRI scans, then correlated with molecular alterations. IDH (IDH1 or IDH2) mutations were found in 58/79 patients (73.4%). IDH mutation, MGMT promoter methylation, and 1p19q codeletion were associated with prolonged progression-free survival in univariate (P < 0.001, P < 0.001, P = 0.003, respectively) and multivariate analysis (P < 0.001, P < 0.001, P = 0.035, respectively). IDH mutation (P = 0.001) and MGMT promoter methylation (P = 0.011) were correlated with a higher rate of objective response to temozolomide. Further analysis of response to temozolomide showed that patients with both IDH mutation and MGMT promoter methylation had the best response rate to temozolomide. IDH mutation appears to be a significant marker of positive chemosensitivity in secondary glioblastoma. Use of IDH status combined with MGMT promoter status as a stratification factor seems appropriate in future clinical trials involving temozolomide for the treatment of patients with secondary glioblastoma.

A simple method for isolating and culturing single cancer stem cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop an effective method for isolating and culturing single cancer stem cells.</p><p><b>METHODS</b>The capillary glass tube was stretched on fire and connected to a sterile plastic tube to prepare the single cell separation apparatus. Single SW480 cell clone spheres in serum-free culture were marked with CD133 and CK7, and the single cancer stem cells were separated and cultivated in 96-well plates or microdrop covered by paraffin.</p><p><b>RESULTS</b>SW480 cell clone formation rate was about 1.04%, and the cell clone spheres highly expressed CD133 with low CK7 expression. The isolation of the single cancer stem cells showed a success rate of 98.99% using the separation device. The cell division profile was comparable between the cell cultures in microdrop and 96-well plates in the initial 2 cell divisions (P>0.05), whereas prolonged cell division occurred afterwards in the microdrop culture as compared to 96-well plate culture. The cell population expansion of the single cancer stem cells was similar between microdrop culture (11.5%, 22/192) and 96-well plate culture (9.2%, 17/184) (P>0.05).</p><p><b>CONCLUSIONS</b>Single SW480 cells can develop into cancer stem cell spheres. Microdrop culture is convenient and stable, and can be the primary choice for single cancer stem cell culture.</p>

LMP1 antagonizes WNT/ß-catenin signalling through inhibition of WTX and promotes nasopharyngeal dysplasia but not tumourigenesis in LMP1(B95-8) transgenic mice.

Latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) can induce cell transformation and tumourigenesis, but the mechanism is not understood. Previous studies have suggested that LMP1 acts through up-regulation of cellular proliferation pathways including the Wnt/ß-catenin pathway, in which ß-catenin is the central effector. Increased levels of ß-catenin coupled with a decrease in E-cadherin lead to reduced cell adhesion. This pathway is antagonized by WTX (Wilms' tumour gene on the X chromosome), which can promote the ubiquitination and degradation of ß-catenin. In the present study, we established L2/LMP1B(95 - 8) /EGFP transgenic mice to investigate the in vivo role of LMP1. Down-regulation of WTX and E-cadherin was accompanied by increased expression of ß-catenin in these mice. Even though invasive tumours did not develop, dysplasia was seen in the nasopharynx and oropharynx epithelium of these transgenic mice. Analysis of LMP1(+) , WTX(+) , and LMP1 siRNA silenced HNE-1 cell lines demonstrated that WTX could exert a dominant role in LMP1-mediated WNT/ß-catenin pathway regulation. This study indicates that LMP1 antagonizes the WNT/ß-catenin pathway by inhibiting WTX, and this reduction in WTX is associated with epithelial dysplasia via regulation of the WNT/ß-catenin pathway molecules E-cadherin and ß-catenin. Further studies are required for a better understanding of the relationship between LMP1-mediated antagonization of the WNT/ß-catenin pathway and tumourigenesis.