a-murine-pancreatic-islet-cell-based-screening-for-diabetogenic

A Murine Pancreatic Islet Cell-based Screening for Diabetogenic Environmental Chemicals

Exposure to certain environmental chemicals in human and animals has been found to cause cellular damage of the pancreatic &#946; cells which will lead to ...

Sun Yat-sen Memorial Hospital

Psychological distress reduces the efficacy of chemotherapy in breast cancer patients. The mechanism may be related to the altered neuronal or hormonal secretions during stress. Here, we reported that adrenaline, a hormone mediating the biological activities of stress, upregulates mdr1 gene expression in MCF-7 breast cancer cells via alpha(2)-adrenergic receptors in a dose-dependent manner. Mdr1 upregulation can be specifically inhibited by pretreatment with mdr1-siRNA. Consequently, adrenergic stimulation enhances the pump function of P-glycoprotein and confers resistance of MCF-7 cells to paclitaxel. In vivo, restraint stress increases mdr1 gene expression in the MCF-7 cancers that are inoculated subcutaneously into the SCID mice and provokes resistance to doxorubicin in the implanted tumors. The effect can be blocked by injection of yohimbine, an alpha(2)-adrenergic inhibitor, but not by metyrapone, a corticosterone synthesis blocker. Therefore, we conclude that breast cancers may develop resistance against chemotherapeutic drugs under psychological distress by over-expressing mdr1 via adrenergic stimulation.

Psychological stress induces chemoresistance in breast cancer by upregulating mdr1.

Emerging evidence has indicated nerve fibers as a marker in the progression of various types of cancers, such as pancreatic cancer and prostate cancer. However, whether nerve fibers are associated with breast cancer progression remains unclear. In this study, we evaluated the presence of nerve fibers in 352 breast cancer specimens and 83 benign breast tissue specimens including 43 cases of cystic fibrosis and 40 cases of fibroadenoma from 2 independent breast tumor center using immunohistochemical staining for specific peripheral nerve fiber markers.In all, nerve fibers were present in 130 out of 352 breast cancer tissue specimens, while none were detected in normal breast tissue specimens. Among 352 cases, we defined 239 cases from Sun Yat-Sen Memorial Hospital, Guangzhou, China, as the training set, and 113 cases from the First Affiliated Hospital of Shantou University, Guangdong, China, as the validation set. The thickness of tumor-involving nerve fibers is significantly correlated with poor differentiation, lymph node metastasis, high clinical staging, and triple negative subtype in breast cancer. More importantly, Cox multifactor analysis indicates that the thickness of tumor-involving nerve fibers is a previously unappreciated independent prognostic factors associated with shorter disease-free survival of breast cancer patients. Our findings are further validated by online Oncomine database. In conclusion, our results show that nerve fiber involvement in breast cancer is associated with progression of the malignancy and warrant further studies in the future.

Nerve fibers in breast cancer tissues indicate aggressive tumor progression.

Because cancer cell invasion is a critical determinant of metastasis, targeting invasion is a viable approach to prevent metastasis. Utilizing a novel three-dimensional high-throughput invasion assay, we screened a National Cancer Institute compound library and discovered compounds demonstrating inhibitory effects on cancer cell invasion. One hit, trifluoperazine, suppresses invasion of human cancer cell lines while displaying a limited cytotoxicity profile. This inhibition is due to the interference with cancer cell migratory ability but not proteolytic activity. Treatment of cancer cells with trifluoperazine significantly reduces angiogenesis and prevents cancer cell invasion through a chorioallantoic basement membrane. Mechanistically, treatment results in decreased phosphorylated AKT (Ser(473) and Thr(308)) and β-catenin (Ser(552)). Lack of phosphorylation of Ser(552) of β-catenin prevents β-catenin nuclear relocation, resulting in decreased expression of vascular endothelial growth factor, likely mediated through dopamine receptor D2. Taken together, we demonstrated that trifluoperazine is responsible for reducing the angiogenic and invasive potential of aggressive cancer cells through dopamine receptor D2 to modulate the β-catenin pathway and propose that trifluoperazine may be used as an antimetastasis chemotherapeutic.

Repurposing the antipsychotic trifluoperazine as an antimetastasis agent.

Chemokine ligand 18 (CCL18) has been associated with hepatocellular carcinoma (HCC) metastasis. Here, we demonstrated a novel mechanism through which CCL18 enhances cell migration, invasion, and epithelial-mesenchymal transition (EMT) in HCC. (1) Using immunohistochemistry, we analyzed the expression of PITPNM3, a molecule that correlated with CCL18 signaling, in 149 HCC tissue specimens. The results showed that PITPNM3 expression is highly associated with tumor metastasis and differentiation; (2) in vitro experiments showed that CCL18 enhances cell migration, invasion, and EMT in PITPNM3((+)) HCC cells but not in PITPNM3((-)) cells. Silencing of PITPNM3 by short interfering RNA (siRNA) inhibited the induction of cell migration, invasion, and EMT by CCL18; (3) Cell migration, invasion, and EMT induced by CCL18 accompanied with the phosphorylation of IKK and IKBα as well as p65 nuclear translocation in PITPNM3((+)) HCC cells, but not in the cells that PITPNM3 is silenced with siRNA, implying that the activation of NF-κB signaling is involved in the action of CCL18/PITPNM3. These results suggest that CCL18 enhances HCC cell migration, invasion, and EMT through the expression of PITPNM3 and the activation of the NF-κB signaling pathway. 

CCL18/PITPNM3 enhances migration, invasion, and EMT through the NF-κB signaling pathway in hepatocellular carcinoma.

The in situ observation on the tissues, such as histopathology, immunohistochemistry (IHC), immunofluorescence (IF), and in situ hybridization (ISH), is one of the most important methods in the biomedical scientific research. In this chapter we introduce the most often used methods-hematoxylin and eosin (H&E) and double IF staining. H&E staining is used for general morphology by which the different pathological types of breast lesions are identified. The double IF staining is often used to study the protein-protein interaction on tissues for signaling mechanisms. This chapter also includes the histopathology of primary or simplified breast lesion types that is essential for applying the above methods and the reclassification of breast cancers by molecular markers. 

Basic Histopathological Methods and Breast Lesion Types for Research.

Breast cancer patients with high proportion of cancer stem cells (BCSCs) have unfavorable clinical outcomes. MicroRNAs (miRNAs) regulate key features of BCSCs. We hypothesized that a biology-driven model based on BCSC-associated miRNAs could predict prognosis for the most common subtype, hormone receptor (HR)-positive, HER2-negative breast cancer patients.

Prognostic Value of a BCSC-associated MicroRNA Signature in Hormone Receptor-Positive HER2-Negative Breast Cancer.

In this study, we examined the relationships between the expression level of CHI3L1 and the clinicopathological characteristics of papillary thyroid carcinoma.

CHI3L1 overexpression is associated with metastasis and is an indicator of poor prognosis in papillary thyroid carcinoma.

The origin of tumor-infiltrating Tregs, critical mediators of tumor immunosuppression, is unclear. Here, we show that tumor-infiltrating naive CD4 T cells and Tregs in human breast cancer have overlapping TCR repertoires, while hardly overlap with circulating Tregs, suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs. Furthermore, the abundance of naive CD4 T cells and Tregs is closely correlated, both indicating poor prognosis for breast cancer patients. Naive CD4 T cells adhere to tumor slices in proportion to the abundance of CCL18-producing macrophages. Moreover, adoptively transferred human naive CD4 T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner. In human breast cancer xenografts in humanized mice, blocking the recruitment of naive CD4 T cells into tumor by knocking down the expression of PITPNM3, a CCL18 receptor, significantly reduces intratumoral Tregs and inhibits tumor progression. These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4 T cells that differentiate into Tregs in situ. Inhibiting naive CD4 T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy.

Blocking the recruitment of naive CD4 T cells reverses immunosuppression in breast cancer.

Middle ear adenoma (MEA) is a rare benign tumour. Here we report a case of MEA in a 39-year-old man with hearing loss. Some significant histopathological features of MEA and neuroendocrine differentiation identified by immunohistochemistry are described. The tumour showed remarkable and rare degenerative histological characteristics. There were a few tumour cells which were covered by degenerated tissue. Consequently, following frozen biopsy, the tumour was misdiagnosed as chronic ear inflammation. No recurrence was seen in this patient after 45 months of follow-up; regular clinical and radiological follow-up is necessary since recurrence is possible. A literature review for MEA is presented and this type of tumour is discussed clinically, microscopically and immunohistochemically. The differential diagnosis and associated treatment are described.

Middle ear adenoma with uncommon presentation and literature review.

The Chinese population typically has inadequate folate intake and no mandatory folic acid fortification. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) are the two key regulatory enzymes in the folate/homocysteine (Hcy) metabolism. Hcy has been implicated in the pathogenesis of cardiovascular disease. We conducted a meta-analysis to assess whether the MTHFR gene A1298C and the MTRR gene A66G polymorphisms affect Hcy levels in the Chinese population.

Effect of MTHFR A1298C and MTRR A66G Genetic Mutations on Homocysteine Levels in the Chinese Population: A Systematic Review and Meta-analysis.

Rho GTPase-activating protein 42 was identified as an inhibitor of RhoA to maintain normal blood pressure homeostasis. However, the effect of ARHGAP42 in promoting cell malignancy in nasopharyngeal carcinoma is demonstrated in this study. Microarray and real-time quantitative PCR were used for a mRNA profiling of ARHGAP42 in nasopharyngeal primary and metastatic carcinoma tissues. Western blot and immunohistochemical staining were used for detecting the expression of ARHGAP42 protein in nasopharyngeal carcinoma tissues and cell lines. The overexpression and silence experiments of ARHGAP42 were performed in NPC cell lines using siRNA and expressive plasmid for evaluating cancer cell migration and invasion in vitro. Real-time quantitative PCR, western blot, and transwell test were employed for with the function of ARHGAP42 and its antisense lncRNA uc010rul. We confirmed the elevated expression of ARHGAP42 in metastatic NPC tissues of mRNA and protein for the first time. Immunohistochemical analysis indicated that NPC patients with highly ARHGAP42 expression were significantly associated with shorter metastasis-free survival. Knockdown of ARHGAP42 resulted in significant inhibition of nasopharyngeal cancer cell migration and invasion in vitro, and the overexpression of ARHGAP42 showed the opposite effects. In addition, the silence of uc010rul resulted in ARHGAP42 expression decrease and significant inhibition of nasopharyngeal cancer cell migration and invasion. High expression of ARHGAP42 is associated with poor metastasis-free survival of nasopharyngeal carcinoma patients. ARHGAP42 promotes migration and invasion of nasopharyngeal carcinoma cells in vitro; the antisense lncRNA may be involved in this effect.

Nengtai Ouyang

Sun Yat-sen Memorial Hospital

A Murine Pancreatic Islet Cell-based Screening for Diabetogenic Environmental Chemicals