Changes in serum uric acid, serum uric acid/serum creatinine ratio, and gamma-glutamyltransferase might predict the efficacy of neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer.

PURPOSE: The purpose of this study was to investigate the predictive value of changes in serum uric acid (SUA), the ratio of serum uric acid to serum creatinine (SUA/SCr), and serum gamma-glutamyltransferase (GGT) from before to after therapy in patients with locally advanced rectal cancer (LARC). METHODS: Data from 114 LARC patients from January 2016 to December 2021 were included in this retrospective study. All patients received neoadjuvant chemoradiotherapy (nCRT) and total mesorectal excision (TME). The change in SUA was calculated as a ratio: (SUA level after nCRT-SUA level before nCRT)/SUA level before nCRT. The change ratios of SUA/SCr and GGT were calculated in the same way. The efficacy of nCRT was evaluated by magnetic resonance (MR) and postoperative pathological response. A nonlinear model was used to evaluate whether the change ratios of SUA, SUA/SCr, and GGT were associated with the efficacy of nCRT. The predictive power of the change ratios of SUA, SUA/SCr, and GGT was assessed by receiver operating characteristic (ROC) curves. Univariate and multivariate Cox regression analyses were employed to measure the associations between disease-free survival (DFS) and other predictive indicators. The Kaplan-Meier method was used to further compare DFS between groups. RESULTS: The nonlinear model indicated that the change ratios of SUA, SUA/SCr, and GGT were associated with the efficacy of nCRT. The change ratios of SUA, SUA/SCr, and GGT were used to predict the area under the ROC curve of efficacy for nCRT (0.95, 0.91-0.99), which was better than the prediction by the change ratio of SUA (0.94, 0.89-0.99), SUA/SCr (0.90, 0.84-0.96), or GGT alone (0.86, 0.79-0.93; p < 0.05). The optimal cut-off values of SUA, SUA/SCr, and GGT change were 0.02, 0.01, and 0.04, respectively. The Kaplan-Meier method indicated that patients with SUA, SUA/SCr, or GGT changes greater than the cut-off values had shorter DFS (p < 0.05). CONCLUSION: Change ratios of SUA, SUA/SCr, or GGT greater than the cut-off values implied a risk of poor pathological response after nCRT and shorter DFS in LARC patients.

Curcumol ß-cyclodextrin inclusion complex enhances radiosensitivity of esophageal cancer under hypoxic and normoxic condition.

PURPOSE: Radiotherapy is an indispensable treatment for esophageal cancer (EC), but radioresistance is not uncommon. Curcumol, as an active extract from traditional Chinese medicines, has been reported to have antitumor activity in various types of human tumor cells. However, its reversal of radioresistance has been rarely reported. MATERIALS AND METHODS: In the present study, curcumol was prepared as an inclusion complex with ß-cyclodextrin. EC cell lines were treated with radiation and curcumol ß-cyclodextrin inclusion complex (CßC), and the effect of radiosensitization of CßC was investigated in vitro and in vivo. The in vitro experiments included cell proliferation assay, clonogenic survival assay, apoptosis assay, cell cycle assay, and western blot assay. RESULTS: The in vitro data revealed that CßC and irradiation synergistically inhibited the proliferation, reduced the colony formation, promoted the apoptosis, increased the G2/M phase, inhibited DNA damage repair, and reversed the hypoxia-mediated radioresistance of EC cells to a greater extent than did CßC alone or irradiation alone. The sensitization enhancement ratios (SERs) were 1.39 for TE-1 and 1.48 for ECA109 under hypoxia. The SERs were 1.25 for TE-1 and 1.32 for ECA109 under normoxia. The in vivo data demonstrated that the combination of CßC and irradiation could inhibit tumor growth to the greatest extent compared with either monotherapy alone. The enhancement factor was 2.45. CONCLUSION: This study demonstrated that CßC could enhance radiosensitivity of EC cells under hypoxic and normoxic condition. Thus, CßC can be used as an effective radiosensitizer for EC.

Radiation-induced mucositis: A retrospective study of dexamethasone-lidocaine-vitamin B12 mouth rinse versus compound chlorhexidine mouthwash in nasopharyngeal carcinoma.

Oral mucositis causes substantial morbidity during head and neck radiotherapy, especially nasopharyngeal carcinoma. During radiotherapy, patients develop severe oral mucositis, which leads to oral pain and difficulty in eating and interruption of radiotherapy, affects the treatment effect and increase the probability of recurrence. Although we have explored various methods to reduce the mucosal damage caused by radiotherapy, these methods still cannot reduce pain caused by mucositis clinically. Therefore, the use of Dexamethasone-Lidocaine-Vitamin B12 Mouth rinse (DLVBM) proved its role in reducing oral mucosal pain, reducing the weight loss of patients, and completing radiotherapy according to the course of treatment. 133 patients with nasopharyngeal carcinoma who received radiotherapy (a total dose of 70 Gy) in our hospital from January to December 2020-2021 were selected. 67 patients received DLVBM treatment for mucositis reaction, and 66 patients received Compound chlorhexidine mouthwash (CCM) to deal with mucositis. Symptoms related to oral mucosal pain score and body weight, mucosal healing time were analyzed retrospectively. We found that patients with the DLVBM group significantly reduced oral pain and reduced weight loss. However, there was no significant difference about the mucosal healing time between the DLVBM group and CCM group. DLVBM may be moderately more effective in preventing radiation-induced mucositis and mucositis-related pain, and their use may lead to less frequent RT course interruptions from mucositis.

miR-18a increases insulin sensitivity by inhibiting PTEN.

The miR-17-92 cluster (miR-17, miR-18a, miR-19a, miR-20a, miR-19b-1 and miR-92a) contributes to the occurrence and development of various diseases by inhibiting multiple target genes. Here, we explored the effects of miR-18a on insulin sensitivity. Quantitative real-time PCR indicated that serum miR-18a levels were lower in type 2 diabetes mellitus patients than in healthy controls, suggesting that miR-18a may influence blood glucose levels. Global overexpression of miR-18a in transgenic mice increased their glucose tolerance and insulin sensitivity, while it reduced expression of the phosphatase and tensin homolog deleted on chromosome ten (PTEN) in their skeletal muscle and adipose tissue. Western blotting indicated that overexpressing miR-18a in 3T3-L1 and C2C12 cells enhanced insulin-stimulated AKT phosphorylation and suppressed PTEN expression, while inhibiting miR-18a had the opposite effects. These results suggest that miR-18a improves insulin sensitivity by downregulating PTEN. This makes miR-18a a potentially useful target for the treatment of diabetes mellitus in the future.

Overexpression of hsa_circ_0136666 predicts poor prognosis and initiates osteosarcoma tumorigenesis through miR-593-3p/ZEB2 pathway.

BACKGROUND: Osteosarcoma (OS) is a type of malignant bone tumor with a growing incidence. Increasing studies indicate circular RNA (circRNA) has a vital function in tumorigenesis. Yet, how circRNA regulates OS development is not clear. In the present work, we aimed to investigate the roles of hsa_circ_0136666 in OS progression. RESULTS: hsa_circ_0136666 was shown to be upregulated in OS and correlated with advanced stage and poor prognosis. Functional investigation using CCK8, colony formation assay and Transwell assay demonstrated that hsa_circ_0136666 promoted OS proliferation, migration and invasion, but inhibited cell death. Additionally, we identified hsa_circ_0136666 was a molecular sponge for miR-593-3p to facilitate ZEB2 expression. MiR-593-3p and ZEB2 were inversely expressed in OS tissues. And hsa_circ_0136666 exerts oncogenic roles in OS relying on miR-593-3p and ZEB2. CONCLUSION: Our results demonstrate the involvement of hsa_circ_0136666 in regulating OS tumorigenesis and it may be a therapeutic target. METHODS: The expression of hsa_circ_0136666 was analyzed by qRT-PCR in OS tissues and cell lines. Proliferation was measured via CCK8 and colony formation assays. Migration and invasion were determined through Transwell assay. Luciferase reporter assay was utilized to determine the interaction between hsa_circ_0136666 and miR-593-3p or between miR-593-3p and ZEB2. Animal experiment was performed to investigate the role of hsa_circ_0136666 in vivo.

Brown Adipose Tissue: A Potential Site for Islet Transplantation.

BACKGROUND: Islet transplantation is a promising treatment in patients with complicated diabetes. The ideal transplant site that can extend islet graft survival and reduce the required number of engrafted islets remains to be established. METHODS: Donor islets were isolated from red fluorescent protein (RFP) mice and transplanted into interscapular brown adipose tissue (BAT) or unilateral inguinal white adipose tissue of age-matched diabetic RFP mice. Blood glucose and body weight of the mice were monitored, and vitality and function of ectopic RFP islets were detected by fluorescence imaging, histological examination, and intraperitoneal glucose tolerance test (GTT). RESULTS: BAT enabled the marginal number of grafted islets (80 islets) to restore blood glucose, insulin level, and GTT to normal values in all diabetic recipient mice in the short term after graft, and maintained these values for 1 year at the end of the experiment. Importantly, in the short term after transplantation, abundant extra- and intraislet neovasculatures were observed in BAT, but not in white adipose tissue, which allowed the ectopic islets to retain typical architecture and morphology and contributed to the normal GTT. Moreover, the islet-engrafted BAT displayed normal structure and morphology without significant immunocyte infiltration, and the recipient mice also showed normal lipid levels in the blood. CONCLUSIONS: BAT remarkably enhances the viability and biological function of the transplanted ectopic islets. Moreover, the anatomical location of BAT lends itself to biopsy, removal, and islet retransplantation, which strongly suggests the BAT as a potential desirable site for islet transplantation in basic and clinical research.

Development of a contouring guide for three different types of optic chiasm: A practical approach.

INTRODUCTION: Sparing of the organs at risk (OARs) is a crucial task in daily radiotherapy practice. Irradiation of the optic chiasm (OC) results in radiation-induced optic neuropathy (RION). The structure of the OC is complex, and OC morphology can vary in axial images. Therefore, a standard atlas can result in inaccurate descriptions of OC morphology in different patients. The aim of our study was to provide a guide based on computed tomography (CT) for the delineation of different types of OC. METHODS: Thirty-six patients were selected to participate in our study. These patients underwent CT analysis of the brain, head and neck regions in a supine position. Axial images 3 mm in thickness were obtained at 3-mm intervals. A magnetic resonance imaging (MRI) study was also performed using the same set-up. The OC was then delineated. The contours were revised by three neuroradiologists and nine radiation oncologists with > 5 years of expertise. RESULTS: Three types of OC were distinguished by magnetic resonance (MR). The location and boundaries of normal, prefixed and postfixed chiasms were developed with a CT-based atlas. Discrepancies were observed in the delineation of the prefixed and postfixed OC. CONCLUSIONS: Our guide allows improved definitions of the anatomical boundaries for different types of OC. Our experience could provide useful information for radiation oncologists in daily practice.

Polydatin inhibits proliferation and promotes apoptosis of doxorubicin-resistant osteosarcoma through LncRNA TUG1 mediated suppression of Akt signaling.

BACKGROUND: Development of doxorubicin-resistance is the main difficulty for osteosarcoma treatment. LncRNA Taurine upregulated gene 1 (TUG1) has been identified as oncogenic lncRNA in different types of carcinomas and was involved in chemoresistance. We aim to evaluate the anti-proliferative effects and the underlying molecular mechanism of Polydatin in doxorubicin-resistant osteosarcoma. METHODS: Doxorubicin-resistant osteosarcoma cell lines were established. MTT, colony formation, apoptosis assay, qRT-PCR and Western blotting analysis, immunohistochemistry and animal study were carried out. RESULTS: It has been showed Polydatin (50-250 µM) inhibited the cell proliferation in a dose- and time-dependent manner at 24 h, 48 h, and 72 h. Polydatin promoted the cell apoptosis significantly with the highest apoptosis rate >50%. Polydatin down-regulated TUG1 expression and TUG1/Akt signaling suppression was involved in Polydatin treated doxorubicin-resistant osteosarcoma cells. The in vivo study further confirmed the anti-cancer effect of Polydatin and related mechanisms. CONCLUSIONS: Polydatin may be a novel therapeutic agent for doxorubicin-resistant osteosarcoma treatment and TUG1 would be a potential molecular target.

PD-L1 Induces Epithelial-Mesenchymal Transition in Nasopharyngeal Carcinoma Cells Through Activation of the PI3K/AKT Pathway.

Nasopharyngeal cancer (NPC) is a malignant epithelial carcinoma of the head and neck. Cancer therapy targeting programmed cell death protein-1 (PD-1) or programmed death ligand-1 (PD-L1) is revolutionary. However, the tumorigenic mechanism of PD-L1 is not yet clear in NPC. Here we demonstrated an oncogenic role of PD-L1 via activating PI3K/AKT in NPC cells. PD-L1 overexpression was frequently detected in NPC biopsies and cell lines by qRT-PCR. PD-L1 overexpression and knockdown demonstrated that PD-L1 promoted NPC cell invasion and metastasis in vitro and in vivo. Mechanistically, PD-L1 prominently activated the epithelial-mesenchymal transition (EMT) process in a PI3K/AKT-dependent manner. Taken together, we found that PD-L1 overexpression confers NPC cell malignancy and aggressiveness via activating the downstream PI3K/AKT signaling. Thus, these results provide a basis for diagnosis and treatment of NPC.

Synaptotagmin-7, a binding protein of P53, inhibits the senescence and promotes the tumorigenicity of lung cancer cells.

Lung cancer has been one of the most common malignancies in the world. Cell senescence has been recognized as the avenue to inhibit tumor progression. However, the mechanisms remain poorly understood. In the present study, we have shown that synaptotagmin-7 (SYT7) expression was up-regulated in lung cancer. SYT7 also promoted the growth and colony formation of lung cancer cells and inhibited their senescence. In a molecular mechanism study, SYT7 was shown to interact with P53 and to potentiate the interaction between P53 and MDM2. Taken together, the present study demonstrates the oncogenic roles of SYT7 in lung cancer, and suggests that SYT7 may be a good therapeutic target for lung cancer treatment.

Artesunate enhances radiosensitivity of esophageal cancer cells by inhibiting the repair of DNA damage.

Radiotherapy plays an important therapeutic role in esophageal cancer (EC). However, acquired radioresistance impairs the efficacy of radiotherapy, often leading to treatment failure. Therefore, it is important to develop novel radiosensitizers to enhance the clinical treatment of EC. The purpose of this study was to investigate the role of artesunate (ART) on radiosensitivity of human EC cell line TE-1. We found that ART inhibited the proliferation of EC cells and enhanced the radiosensitivity of TE-1 cells (SER = 1.24). In vivo tumor growth of xenografts was inhibited markedly by irradiation (IR) combined with ART, with a tumor inhibition rate of 53.76% in IR + ART group vs. 41.13% in IR-alone group. Pretreatment with ART significantly prompted cell apoptosis and reversed the IR-induced G2/M arrest. ART treatment could aggravate DNA damage of EC cells and prolong the formation of γ-H2AX foci induced by IR. ART up-regulated P21 and down-regulated the expression of cyclin D1, RAD51, RAD54, Ku70 and Ku86 protein of irradiated TE-1 cells. These findings support that ART induce radiosensitivity of TE-1 cells in vitro and in vivo, and may prove to be a promising radiosensitizer for EC treatment.

LncRNA HAND2-AS1 sponging miR-1275 suppresses colorectal cancer progression by upregulating KLF14.

Long noncoding RNAs (lncRNAs) represent a novel type of noncoding RNAs of over 200 nucleotides, characterized by no or limited protein-coding potential. Although the function of lncRNAs attracts increasing attention recently, the relationship between lncRNA and colorectal cancer (CRC) remains further investigation. In our study, we found that lncRNA HAND2-AS1 was markedly downregulated in CRC tissues. And its expression level was negatively correlated with metastasis and advanced stage in CRC patients. Furthermore, we showed that HAND2-AS1 low expression predicted poor prognosis. Functionally, we found that overexpression of HAND2-AS1 obviously attenuated the proliferation and invasion of CRC cells. Ectopic expression of HAND2-AS1 also inhibited tumor propagation in vivo. In mechanism, HAND2-AS1 served as a sponge of miR-1275 which targeted KLF14. Through facilitating KLF14 expression, HAND2-AS1 suppressed CRC progression. In conclusion, our study demonstrated that HAND2-AS1 exerts a suppressive role in CRC by sponging miR-1275 and modulating KLF14 expression.

T2 relaxation time for intervertebral disc degeneration in patients with upper back pain: initial results on the clinical use of 3.0 Tesla MRI.

BACKGROUND: Magnetic resonance imaging (MRI) is a useful non-invasive tool for evaluating abnormalities of intervertebral discs. However, there are few studies which applied functional MRI techniques to investigate degenerative changes in cervical and cervicothoracic junction (CTJ) spine among adults. The aim of this study was to compare T2 relaxation time measurement evaluation with morphological grading for assessing cervical and CTJ intervertebral discs (IVD) in the patients suffering neck, shoulder, and upper back pain. METHODS: Sixty-three patients (378 IVDs) and 60 asymptomatic volunteers (360 IVDs) of the cervical and CTJ discs were assessed using a 3.0 T magnetic resonance imaging (MRI) protocol, including an sagittal T2 relaxation time protocol. The relaxation time values of the nucleus pulposus (NP) were recorded and all discs were visually graded according to Pfirrman's grading system. The correlation between T2 relaxation time values and qualitative clinical grading of degeneration, patient age, sex and anatomic level were analyzed RESULTS: There is a clear trend of decreasing mean T2 values of the NP associate with increasing Pfirrmann grades (C2-T1) for both patients and asymptotic volunteers. Significant T2 differences were seen among grades I-V (P < 0.05). However, grade V was not observed in the CTJ. Linear correlation analysis revealed a strong negative association between T2 values of the NP and Pfirrmann grade (r = -0.588, r = -0.808) of C2-7 and C7T1. Age were also significantly correlated NP T2 values (r = -0.525, r = -0.723) for patients and volunteers. Moreover, the receiver operating characteristic analysis for average measures in a range from 0.70-0.79 (C2-7) to 0.84-0.89 (C7T1) for patients. CONCLUSIONS: T2 quantitation provides a more sensitive and robust approach for detecting and characterizing the early stage of IVD degeneration and age-associated disc changes.

Ectopic expression of Cripto-1 in transgenic mouse embryos causes hemorrhages, fatal cardiac defects and embryonic lethality.

Targeted disruption of Cripto-1 in mice caused embryonic lethality at E7.5, whereas we unexpectedly found that ectopic Cripto-1 expression in mouse embryos also led to embryonic lethality, which prompted us to characterize the causes and mechanisms underlying embryonic death due to ectopic Cripto-1 expression. RCLG/EIIa-Cre embryos displayed complex phenotypes between embryonic day 14.5 (E14.5) and E17.5, including fatal hemorrhages (E14.5-E15.5), embryo resorption (E14.5-E17.5), pale body surface (E14.5-E16.5) and no abnormal appearance (E14.5-E16.5). Macroscopic and histological examination revealed that ectopic expression of Cripto-1 transgene in RCLG/EIIa-Cre embryos resulted in lethal cardiac defects, as evidenced by cardiac malformations, myocardial thinning, failed assembly of striated myofibrils and lack of heartbeat. In addition, Cripto-1 transgene activation beginning after E8.5 also caused the aforementioned lethal cardiac defects in mouse embryos. Furthermore, ectopic Cripto-1 expression in embryonic hearts reduced the expression of cardiac transcription factors, which is at least partially responsible for the aforementioned lethal cardiac defects. Our results suggest that hemorrhages and cardiac abnormalities are two important lethal factors in Cripto-1 transgenic mice. Taken together, these findings are the first to demonstrate that sustained Cripto-1 transgene expression after E11.5 causes fatal hemorrhages and lethal cardiac defects, leading to embryonic death at E14.5-17.5.

MiR-17-5p promotes cancer cell proliferation and tumorigenesis in nasopharyngeal carcinoma by targeting p21.

MicroRNAs (miRNAs) may act as either tumor suppressors or oncogenes in various types of cancers. Previous studies have indicated that miR-17-5p is involved in the initiation and development of human tumors. However, its mechanism and function in nasopharyngeal carcinoma (NPC) remain largely unclear. In this study, we evaluated the expression profiles of miR-17-5p and p21 in NPC cell lines and tissues by quantitative real-time PCR (qRT-PCR). For the analysis, we have established a stable overexpression or depletion of miR-17-5p NPC cell lines for analyzing the effects of cell proliferation by MTT, colony formation, and cell cycle assay. A nude mice xenograft model was used to verify the tumor growth in vivo. MiR-17-5p was overexpressed, whereas the expression of p21 was downregulated in NPC cell lines and tissues. The miR-17-5p expression level was inversely correlated with the p21 mRNA level in NPC samples. Furthermore, analysis of 2-ΔΔCt value in 81 NPC patients suggested that the elevated expression level of miR-17-5p or the downregulated expression level of p21 was significantly correlated with tumor size (T classification) and tumor stage, and Kaplan-Meier survival analysis revealed a correlation between miR-17-5p or p21 expression level and overall survival times in 81 NPC patients. MiR-17-5p promoted cell growth in vivo and in vitro by directly targeting p21. Our results indicate that miR-17-5p can promote the occurrence of NPC and it may serve as a potential novel diagnostic maker or therapeutic target for NPC in the future.

MiR-155 Enhances Insulin Sensitivity by Coordinated Regulation of Multiple Genes in Mice.

miR-155 plays critical roles in numerous physiological and pathological processes, however, its function in the regulation of blood glucose homeostasis and insulin sensitivity and underlying mechanisms remain unknown. Here, we reveal that miR-155 levels are downregulated in serum from type 2 diabetes (T2D) patients, suggesting that miR-155 might be involved in blood glucose control and diabetes. Gain-of-function and loss-of-function studies in mice demonstrate that miR-155 has no effects on the pancreatic ß-cell proliferation and function. Global transgenic overexpression of miR-155 in mice leads to hypoglycaemia, improved glucose tolerance and insulin sensitivity. Conversely, miR-155 deficiency in mice causes hyperglycemia, impaired glucose tolerance and insulin resistance. In addition, consistent with a positive regulatory role of miR-155 in glucose metabolism, miR-155 positively modulates glucose uptake in all cell types examined, while mice overexpressing miR-155 transgene show enhanced glycolysis, and insulin-stimulated AKT and IRS-1 phosphorylation in liver, adipose tissue or skeletal muscle. Furthermore, we reveal these aforementioned phenomena occur, at least partially, through miR-155-mediated repression of important negative regulators (i.e. C/EBPß, HDAC4 and SOCS1) of insulin signaling. Taken together, these findings demonstrate, for the first time, that miR-155 is a positive regulator of insulin sensitivity with potential applications for diabetes treatment.

Recognition and killing of cancer stem-like cell population in hepatocellular carcinoma cells by cytokine-induced killer cells via NKG2d-ligands recognition.

There is an urgent need for more potent and safer approaches to eradicate cancer stem cells (CSCs) for curing cancer. In this study, we investigate cancer-killing activity (CKA) of cytokine-induced killer (CIK) cells against CSCs of hepatocellular carcinoma (HCC). To visualize CSCs in vitro by fluorescence imaging, and image and quantify CSCs in tumor xenograft-bearing mice by bioluminescence imaging, HCC cells were engineered with CSC detector vector encoding GFP and luciferase controlled by Nanog promoter. We found that CIK cells have a strong CKA in vitro against putative CSCs of HCC, as shown by tumorsphere formation and time-lapse imaging. Additionally, time-lapse recording firstly revealed that putative CSCs were attacked simultaneously by many CIK cells and finally eradicated by CIK cells, indicating the necessity of achieving sufficient effector-to-target ratios. We firstly illustrated that anti-NKG2D antibody blocking partially but significantly inhibited CKA of CIK cells against putative CSCs. More importantly, intravenous infusion of CIK cells remarkably delayed tumor growth in mice with a significant decrease in putative CSC number monitored by bioluminescence imaging. Taken together, these findings demonstrate CKA of CIK cells against putative CSCs of HCC, at least in part, by NKG2D-ligands recognition.

Targeted Disruption of miR-17-92 Impairs Mouse Spermatogenesis by Activating mTOR Signaling Pathway.

The miR-17-92 cluster and its 6 different mature microRNAs, including miR-17, miR-18a, miR-19a, miR-20a, miR-19b-1, and miR-92a, play important roles in embryo development, immune system, kidney and heart development, adipose differentiation, aging, and tumorigenicity. Currently, increasing evidence indicates that some members of miR-17-92 cluster may be critical players in spermatogenesis, including miR-17, miR-18a, and miR-20a. However, the roles and underlying mechanisms of miR-17-92 in spermatogenesis remain largely unknown. Our results showed that the targeted disruption of miR-17-92 in the testes of adult mice resulted in severe testicular atrophy, empty seminiferous tubules, and depressed sperm production. This phenotype is partly because of the reduced number of spermatogonia and spermatogonial stem cells, and the significantly increased germ cell apoptosis in the testes of miR-17-92-deficient mice. In addition, overactivation of the mammalian target of rapamycin signaling pathway and upregulation of the pro-apoptotic protein Bim, Stat3, c-Kit, and Socs3 were also observed in miR-17-92-deficient mouse testes, which might be, at least partially if not all, responsible for the aforementioned phenotypic changes in mutant testes. Taken together, these findings suggest that miR-17-92 is essential for normal spermatogenesis in mice.

Simple and rapid determination of homozygous transgenic mice via in vivo fluorescence imaging.

Setting up breeding programs for transgenic mouse strains require to distinguish homozygous from the heterozygous transgenic animals. The combinational use of the fluorescence reporter transgene and small animal in-vivo imaging system might allow us to rapidly and visually determine the transgenic mice homozygous for transgene(s) by the in vivo fluorescence imaging. RLG, RCLG or Rm17LG transgenic mice ubiquitously express red fluorescent protein (RFP). To identify homozygous RLG transgenic mice, whole-body fluorescence imaging for all of newborn F2-generation littermates produced by mating of RFP-positive heterozygous transgenic mice (F1-generation) derived from the same transgenic founder was performed. Subsequently, the immediate data analysis of the in vivo fluorescence imaging was carried out, which greatly facilitated us to rapidly and readily distinguish RLG transgenic individual(s) with strong fluorescence from the rest of F2-generation littermates, followed by further determining this/these RLG individual(s) showing strong fluorescence to be homozygous, as strongly confirmed by mouse mating. Additionally, homozygous RCLG or Rm17LG transgenic mice were also rapidly and precisely distinguished by the above-mentioned optical approach. This approach allowed us within the shortest time period to obtain 10, 8 and 2 transgenic mice homozygous for RLG, RCLG and Rm17LG transgene, respectively, as verified by mouse mating, indicating the practicality and reliability of this optical method. Taken together, our findings fully demonstrate that the in vivo fluorescence imaging offers a visual, rapid and reliable alternative method to the traditional approaches (i.e., mouse mating and real-time quantitative PCR) in identifying homozygous transgenic mice harboring fluorescence reporter transgene under the control of a ubiquitous promoter in the situation mentioned in this study.

Hes1 triggers epithelial-mesenchymal transition (EMT)-like cellular marker alterations and promotes invasion and metastasis of nasopharyngeal carcinoma by activating the PTEN/AKT pathway.

Overexpression of the transcriptional factor Hes1 (hairy and enhancer of split-1) has been observed in numerous cancers, but the precise roles of Hes1 in epithelial-mesenchymal transition (EMT), cancer invasion and metastasis remain unknown. Our current study firstly revealed that Hes1 upregulation in a cohort of human nasopharyngeal carcinoma (NPC) biopsies is significantly associated with the EMT, invasive and metastatic phenotypes of cancer. In the present study, we found that Hes1 overexpression triggered EMT-like cellular marker alterations of NPC cells, whereas knockdown of Hes1 through shRNA reversed the EMT-like phenotypes, as strongly supported by Hes1-mediated EMT in NPC clinical specimens described above. Gain-of-function and loss-of-function experiments demonstrated that Hes1 promoted the migration and invasion of NPC cells in vitro. In addition, exogenous expression of Hes1 significantly enhanced the metastatic ability of NPC cells in vivo. Chromatin immunoprecipitation (ChIP) assays showed that Hes1 inhibited PTEN expression in NPC cells through binding to PTEN promoter region. Increased Hes1 expression and decreased PTEN expression were also observed in a cohort of NPC biopsies. Additional studies demonstrated that Hes1-induced EMT-like molecular changes and increased motility and invasion of NPC cells were mediated by PTEN. Taken together, our results suggest, for what we believe is the first time, that Hes1 plays an important role in the invasion and metastasis of NPC through inhibiting PTEN expression to trigger EMT-like phenotypes.