miR-21 targets Fas ligand-mediated apoptosis in breast cancer cell line MCF-7.

Over-expression of Fas ligand (FasL) on tumor cell surface can induce the apoptosis of specific activated tumor infiltrating lymphocytes (TILs) via the Fas/FasL pathway, leading to the formation of a site of immune privilege surrounding the tumor mass for escaping immune surveillance and promoting tumor proliferation, invasion and metastasis. The blocking effect of miR-21 on FasL-mediated apoptosis in breast cancers was investigated in this study. The expression levels of miR-21 and FasL in human breast carcinoma cell lines were detected by using RT-PCR and Western blotting. FasL as a target gene of miR-21 was identified by Luciferase assay. The apoptosis of Jurkat T lymphocytes induced by MCF-7 cells was determined by flow cytometry. It was found that in four human breast cancer cell lines, FasL expression level in MCF-7 cells was the highest, while miR-21 was down-regulated the most notably. After miR-21 expression in MCF-7 cells was up-regulated, FasL was identified as a target gene of miR-21. When the effector/target (E/T) ratio of MCF-7 cells and Jurkat cells was 10:1, 5:1 and 1:1, the inhibitory rate of apoptosis of Jurkat T lymphocytes induced by MCF-7 cells was 95.81%, 93.16% and 91.94%, respectively. It is suggested that in breast cancers miR-21 expression is negatively associated with FasL expression, and FasL is a target gene of miR-21. miR-21 targeting and regulating FasL-mediated apoptosis will bring us the possibility of a new tumor immunotherapy via breaking tumor immune privilege.

Complete mitochondrial genome sequence of Acer miaotaiense (Aceraceae).

Acer miaotaiense P. C. Tsoong is a rare and endangered tree endemic to the Qinling Mountains of China and is listed as a national third-class protected plant. In this study, we sequenced the complete mitochondrial genome of Acer miaotaiense using the Illumina Novaseq 6000 and Nanopore platforms. The total mitochondrial genome length is 819,227 bp and has 69 genes, including 41 protein-coding, 25 tRNA, and 3 rRNA genes. The genome nucleotide composition was asymmetric, with an overall G + C content of 45.7%. Phylogenetic analysis indicated that Acer miaotaiense is closely related to the congeneric Acer yangbiense.

Tianeptine reverses stress-induced asymmetrical hippocampal volume and N-acetylaspartate loss in rats: an in vivo study.

Stress-induced hippocampal volume loss and decrease in N-acetylaspartate (NAA) level have been reported to be associated with impaired neural plasticity and neuronal damage in adults. Accordingly, reversing structural and metabolite damage in the hippocampus may be a desirable goal for antidepressant therapy. The present study investigated the effects of tianeptine on chronic stress-induced hippocampal volume loss and metabolite alterations in vivo in 24 Sprague-Dawley rats. Rats were subjected to a consecutive 28-day forced swimming test stress. Tianeptine (50mg/kg) or saline was administered intragastrically 4h after swimming each day. Spontaneous behaviors, serum corticosterone concentration, hippocampal volume and NAA level were evaluated after stress. Chronic tianeptine treatment counteracted the chronic stress-induced suppression of spontaneous behaviors, elevated serum corticosterone concentration, reduced hippocampal volume and decreased NAA level. Moreover, we found asymmetrical right-left hippocampal volume loss in stressed rats, with the left hippocampus more sensitive to chronic stress than the right hippocampus. In addition, stressed rats showed a decreased level of hippocampal metabolites, without significant loss of hippocampal volume. These findings provide experimental evidence for impaired structural plasticity of the brain being an important feature of depressive illness and suggest that prophylactic tianeptine treatments could reverse structural changes in brain. The structural and neurochemical alterations in the hippocampus may be valuable indexes for evaluating the prophylactic and curative effect of antidepressant treatments in depressive and stress-related disorders.

Characterization of the complete chloroplast genome of Tilia taishanensis S. B. Liang (Tiliaceae).

The complete chloroplast genome of an endangered endemic species in China Tilia taishanensis was sequenced with Illumina HiSeq 2000 platform. It was a typical quadruple structure as other plants of Tilia with 162,803 bp in length, including a large single copy (LSC: 91,114 bp) region and a small single copy (SSC: 20,379 bp) which were separated by a pair of inverted repeats (IRa, b: 25,655 bp) region. The overall GC content is 36.5%. A total of 129 genes was annotated which contained 84 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. ML Phylogenetic analysis compared with 33 expressed chloroplast genomes revealed that T. taishanensis was a sister to other Tilia species.

The complete chloroplast genome of Catalpa 'Bairihua', a hybrid variety with multi season flowering.

The complete chloroplast genome of Catalpa 'Bairihua' a hybrid variety with multi season flowering obtained from hybrid progeny of C. bungei 'Luoqiu Sihao' (C. bungei '01' × C. bungei 'Changguo Qiu') and C. fargesii f. duclouxii was first sequenced with the Illumina HiSeq 2000 platform. Which was 158,210 bp in length with a typical quadruple structure and contained a large single copy (LSC: 84,928 bp) region and a small single copy (SSC: 12,664 bp) region that were separated by a pair of inverted repeats (IRa, b: 30,309 bp) region. The GC content of the whole chloroplast genome is 38.1%. A total of 130 genes was annotated in the complete chloroplast genome, including 85 protein-coding genes, 37 tRNA genes and 8rRNA genes. ML phylogenetic analysis by comparing with 39 chloroplast genomes of the Bignoniaceae indicated that Catalpa 'Bairihua' was close to Tecomaria capensis.

Role of Hedgehog signaling pathway in proliferation and invasiveness of hepatocellular carcinoma cells.

The Hedgehog (Hh) pathway has been confirmed a contributor to the carcinogenesis and progression of various tumor types. To investigate the Hh signaling activity in human hepatocellular carcinoma (HCC), we detected the expression levels of Hh pathway components (Shh, Ptch1 and Gli2) in 57 samples of HCC and corresponding adjacent-tumor liver tissues. The Hh pathway was overexpressed in cancer tissues compared with non-cancer tissues and correlated closely with histologic differentiation and portal venous invasion of HCC. To elucidate the relationship between Hh signaling and HCC progression, we performed a further study in vitro. First, the expression levels of the signaling were detected in a subset of hepatoma cell lines and SMMC-7721 cells selected with high level of Hh signaling expression. Next, we employed KAAD-cyclopamine (a specific inhibitor of Hedgehog pathway) to block the Hh pathway in SMMC-7721 cells and assessed the changes of their biological behaviors. The results showed that the blockade of Hh signaling pathway by KAAD-cyclopamine induced reduction of DNA synthesis leading to marked cell growth inhibition and also caused significant attenuation in invasiveness and motility of HCC cells. Collectively, our data demonstrated that the Hh pathway plays an important role in HCC development and invasion. Blockade of the Hh signaling pathway may be a potential target of new therapeutic strategy for HCC.

Protective effect of granulocyte colony-stimulating factor on intracerebral hemorrhage in rat.

Granulocyte colony-stimulating factor (G-CSF) is a member of the cytokine family of growth factors that can protect the neurons from focal cerebral ischemia-induced injuries. The intracerebral hemorrhage (ICH) has been widely observed in the clinic; however, the protective effect of G-CSF on ICH is still elusive. We found in the present study that the intraperitoneal injection of G-CSF for 5 days could improve the ICH-induced neuronal behavioral impairment measured by limb placement assay. We also observed that injection of G-CSF could increase the number of stem cells in the specific zone of the hemorrhagic areas, demonstrated by the enhanced expression of nestin. Additionally, G-CSF could also promote the mobilization of circulating hemopoietic stem cells (HSCs) to the damaged brain areas and activate the astrocytes. Our results reveal that G-CSF is also protective for the ICH with the mechanisms involving proliferation of neural stem cells, the migration of HSCs and the activation of astrocytes.

Bis(7)-tacrine prevents glutamate-induced excitotoxicity more potently than memantine by selectively inhibiting NMDA receptors.

We have recently reported that bis(7)-tacrine could prevent glutamate-induced neuronal apoptosis through NMDA receptors. In this study, we demonstrated that in cultured rat cortical neurons, bis(7)-tacrine (IC(50), 0.02 microM) prevented glutamate-induced excitotoxicity more substantially than memantine (IC(50), 0.7 microM). In addition, bis(7)-tacrine was more efficient than memantine in buffering the intracellular Ca(2+) triggered by glutamate. In cultured rat hippocampal neurons, bis(7)-tacrine inhibited 50 microM NMDA-activated current in a concentration-dependent manner with an IC(50) of 0.68+/-0.07 microM, which is five times more potent than that produced by memantine (IC(50), 3.41+/-0.36 microM; p<0.05). By contrast, bis(7)-tacrine, up to 5 microM, did not significantly affect the current activated by 50 microM AMPA or 50 microM kainate. These results suggest that bis(7)-tacrine is more potent than memantine against glutamate-induced neurotoxicity by selectively inhibiting NMDA-activated current.

Inhibition of NMDA-gated ion channels by bis(7)-tacrine: whole-cell and single-channel studies.

Bis(7)-tacrine is a novel dimeric acetylcholinesterase inhibitor derived from tacrine, and has been proposed as a promising agent to treat Alzheimer's disease. We have recently reported that bis(7)-tacrine prevents glutamate-induced neuronal apoptosis by antagonizing NMDA receptors. The purpose of this study was to characterize bis(7)-tacrine inhibition of NMDA-activated current by using patch-clamp recording techniques. In cultured rat hippocampal neurons, bis(7)-tacrine inhibited NMDA-activated whole-cell current in a concentration-dependent manner with an IC(50) of 0.66+/-0.07 microM. Bis(7)-tacrine produced a gradual decline of NMDA-activated current to a steady-state, but this was not an indication of use-dependence. Also, the slow onset of inhibition by bis(7)-tacrine was not apparently due to an action at an intracellular site. Bis(7)-tacrine, 0.5 microM, decreased the maximal response to NMDA by 40% without changing its EC(50). Bis(7)-tacrine inhibition of NMDA-activated current was not voltage-dependent, and was independent of glycine concentration. Results of single-channel experiments obtained from cells expressing NR1 and NR2A subunits revealed that bis(7)-tacrine decreased the open probability and frequency of channel opening, but did not significantly alter the mean open time or introduce rapid closures. These results suggest that bis(7)-tacrine can inhibit NMDA receptor function in a manner that is slow in onset and offset and noncompetitive with respect to both NMDA and glycine. The noncompetitive inhibition of NMDA receptors by bis(7)-tacrine could contribute to its protective effect against glutamate-induced neurotoxicity.

Significance of Survivin and PTEN expression in full lymph node-examined gastric cancer.

AIM: To study the relationship between Survivin and PTEN expression and lymph node metastasis, depth of invasion and prognosis of gastric cancer patients in China. METHODS: Specimens of gastric cancer tissue were collected from the Affiliated Hospital of Jianghan University. All the 140 patients had complete examination data. All lymph nodes were found by the fat-clearing method. The interrupted serial 4-micron sections, routine hematoxylin and eosin staining and immunohistochemical methods were used to detect the lymph node metastases. Gastric cancer tissue microarray was performed to test the expression of Survivin and PTEN (17A) in gastric cancer by immunohistochemical method. All data were processed using chi2 test, Fisher's exact test, Kaplan-Meyer Log-rank method and Cox multivariate analysis (SPSS 12.0 software). RESULTS: One hundred and eighteen specimens were used in our tissue microarray (utilization rate was 82.4%). A total of 7580 lymph nodes were found. Metastases were found in 90 specimens and 1618 lymph nodes were detected. The positive rate of Survivin and PTEN expression was 52.5% (62/118) and 76.2% (90/118), respectively. A highly positive correlation was found between Survivin and PTEN expression (chi2 = 4.17, P = 0.04). Survivin expression was positively correlated with UICC N stage (chi 2 = 8.69, P = 0.03) and histological classification (chi2 = 4.41, P = 0.04) by chi2 tests. PTEN expression was positively correlated with depth of invasion (P = 0.02) and histological classification (chi2 = 5.47, P = 0.02). But Survivin and PTEN expressions were not related with prognosis of gastric cancer patients. A significant correlation between lymph node metastasis and prognosis was demonstrated by Cox multivariate analysis (chi2 = 4.85, P = 0.028). CONCLUSION: Survivin is positively correlated with PTEN expression in gastric cancer and is a molecular marker of lymph node metastasis while PTEN expression is a molecular marker of advanced gastric cancer. UICC N stage is the most important prognostic factor of gastric cancer in China.

Ultrastructural changes in non-specific duodenitis.

AIM: To investigate the ultrastructural and morphological changes of non-specific duodenitis (NSD) in an attempt to grade them according to the extent of the lesions. METHODS: Biopsies were taken from the mucosa of duodenal bulb of 44 patients selected from the patients undergoing upper gastrointestinal endoscopy for epigastric discomforts. From each patient, two pinch biopsies on the same area were obtained from duodenal bulb. One was for scanning electron microscopy and the other was stained with hematoxylin-eosin, Warthin-Starry silver and both were then examined under light microscope. A total of 12 specimens (three from each degree of the normal and I-III of NSD diagnosed and graded by histology) selected from the 44 patients were dehydrated, critical point dried, coated with gold palladium and examined under a JEOL JSM-30 scanning electron microscope (SEM) at 20 kV. RESULTS: According to the ultrastructural morphologic changes, non-specific duodenitis was divided into normal (as control group), mild, moderate and severe degrees according to results of SEM. The normal villi of duodenal bulb were less than 0.2 mm. There were inflammation cells, occasionally red blood cells and macrophages on the mucosal epithelial surface. Erosion and desquamation of epithelium could be seen. Three cases (25%, 3/12) had gastric metaplasia and Helicobacter pylori (H pylori) infection could be found in 5 cases (41.67%, 5/12) in duodenal bulb mucosa. The most distinctive feature was the ulcer-like defect on the surface of epithelial cells. CONCLUSION: Non-specific duodenitis is a separate entity disease caused by different factors. SEM is of value as an aid in the diagnosis of mucosal diseases of duodenum.

[Study on relationship between changes of geometry parameters in human spleen nuclei and the postmortem interval].

OBJECTIVE: Using computer image-analyze technique (CIAT) to study changes of geometry parameters in human spleen nuclei and seek a new experimental method to deduce the estimation the postmortem interval (PMI). METHODS: 31 cadavers that known accurate PMI, sampled and smeared respectively every hour within the first 36 hours after death, fixed with cold Carony fixation, stained by Feulgen-van's method, and measured 5 geometry parameters using the image-analyze instrument including Area (A), Mean-Dia (MD), Average Diameter (AD), perimeter (P), Index of density (ID). RESULTS: A, MD, AD and P in the human spleen nuclei have no correlation with the PMI. But ID rose regularly with the prolongation of PMI in 36 hours. There was a definite correlation between ID and the PMI, r=0.983, linear regression equation with PMI (hours) as the dependent variable was calculated for ID. CONCLUSION: Geometry parameter ID was proved to be preferable indexes for estimation of PMI in 36 hours.

Interleukin-6-induced epithelial-mesenchymal transition through signal transducer and activator of transcription 3 in human cervical carcinoma.

Epithelial-mesenchymal transition (EMT) is an important process in the invasion and metastasis of human cervical carcinoma. The pro-inflammatory cytokine interleukin-6 (IL-6) has been shown as an EMT inducer in multiple carcinomas. However, whether the EMT program can be induced by IL-6 and the mechanisms underlying the IL-6-induced EMT in human cervical carcinoma remain to be determined. In this study, we show that IL-6 receptor (IL-6R) and signal transducer and activator of transcription 3 (Stat3) were highly expressed in human cervical squamous cell carcinoma (CSCC) tissues, and the expression of EMT markers was reversed in well-differentiated and poorly-differentiated human CSCC. Additional experiments showed that IL-6 exposure in cervical carcinoma cell lines induced IL-6R and Stat3 expression, markedly promoted cell growth, and altered cell morphology. The treatment of cervical carcinoma cell lines with IL-6 resulted in downregulation of E-Cadherin and upregulation of Vimentin. Importantly, knockdown of Stat3 significantly reversed the IL-6-induced EMT program, suggesting that Stat3 is necessary for IL-6-induced EMT in the progression of human cervical carcinoma. Moreover, Slug, a member of the Snail family of EMT regulators, was observed to be associated with the expression of Stat3. We concluded that IL-6 plays an important role through Stat3 in the EMT induction and can be a potential therapeutic target and biomarker for human cervical carcinoma.

ER-α variant ER-α36 mediates antiestrogen resistance in ER-positive breast cancer stem/progenitor cells.

Accumulating evidence indicates that cancer stem cells (CSC) play important roles in breast cancer occurrence, recurrence and metastasis as well as resistance to therapy. However, the roles of breast cancer stem cells in antiestrogen resistance and the underlying molecular mechanisms have not been well established. Previously, we identified and cloned a novel variant of estrogen receptor α, ER-α36, with a molecular weight of 36kDa. ER-α36 mediates rapid antiestrogen signaling and is highly expressed in ER-positive breast cancer stem/progenitor cells. In this study, we investigated the function and the underlying mechanism of ER-α36-mediated antiestrogen signaling in ER-positive breast cancer stem/progenitor cells. ER-positive breast cancer cells MCF7 and T47D as well as variants with different levels of ER-α36 expression were used. The effects of antiestrogens tamoxifen and ICI 182, 780 on breast CSC's ability of growth, self-renewal, differentiation and tumor seeding were examined using tumorsphere formation, flow cytometry, indirect immunofluorences and in vivo xenograft assays. The underlying mechanisms were also analyzed with Western blot analysis. We found that the cancer stem/progenitor cells enriched from ER-positive breast cancer cells were more resistant to antiestrogens than the bulk cells. Antiestrogens increased the percentages of the stem/progenitor cells from ER-positive breast cancer cell through stimulation of luminal epithelial lineage specific ER-positive breast cancer progenitor cells while failed to do so in the cells with knocked-down levels of ER-α36 expression. Our results thus indicated that ER-α36-mediated antiestrogen signaling such as the PI3K/AKT plays an important role in antiestrogen resistance of ER-positive breast cancer stem/progenitor cells.

ER-α36-mediated rapid estrogen signaling positively regulates ER-positive breast cancer stem/progenitor cells.

The breast cancer stem cells (BCSC) play important roles in breast cancer occurrence, recurrence and metastasis. However, the role of estrogen signaling, a signaling pathway important in development and progression of breast cancer, in regulation of BCSC has not been well established. Previously, we identified and cloned a variant of estrogen receptor α, ER-α36, with a molecular weight of 36 kDa. ER-α36 lacks both transactivation domains AF-1 and AF-2 of the 66 kDa full-length ER-α (ER-α66) and mediates rapid estrogen signaling to promote proliferation of breast cancer cells. In this study, we aim to investigate the function and the underlying mechanism of ER-α36-mediated rapid estrogen signaling in growth regulation of the ER-positive breast cancer stem/progenitor cells. ER-positive breast cancer cells MCF7 and T47D as well as the variants with different levels of ER-α36 expression were used. The effects of estrogen on BCSC's abilities of growth, self-renewal, differentiation and tumor-seeding were examined using tumorsphere formation, flow cytometry, indirect immunofluorence staining and in vivo xenograft assays. The underlying mechanisms were also studied with Western-blot analysis. We found that 17-ß-estradiol (E2ß) treatment increased the population of ER-positive breast cancer stem/progenitor cells while failed to do so in the cells with knocked-down levels of ER-α36 expression. Cells with forced expression of recombinant ER-α36, however, responded strongly to E2ß treatment by increasing growth in vitro and tumor-seeding efficiency in vivo. The rapid estrogen signaling via the AKT/GSK3ß pathway is involved in estrogen-stimulated growth of ER-positive breast cancer stem/progenitor cells. We concluded that ER-α36-mediated rapid estrogen signaling plays an important role in regulation and maintenance of ER-positive breast cancer stem/progenitor cells.

[Prognostic significance of lymph node micrometastasis in colorectal cancer].

BACKGROUND & OBJECTIVE: There have been many controversies about the prognostic significance of lymph node micrometastasis. The aim of this study was to characterize the prognostic significance of lymph node micrometastasis of colorectal cancer. METHODS: Specimens of curative resection between 1988 and 2001 were collected from The Affiliated Hospital of Jianghan University Medical and Life Science College. All 80 patients (30 cases of rectal cancer, 50 cases of colon cancer) had complete examination data. A total of 3869 lymph nodes (48.36 per case) were found by clearing fat method. The interrupted serial 4-micron sections, routine hematoxylin and eosin staining and immunohistochemistry methods were used to detect the lymph node metastasis and micrometastasis (small tumor cells cluster diameter