Acinous cell AR42J-derived exosome miR125b-5p promotes acute pancreatitis exacerbation by inhibiting M2 macrophage polarization via PI3K/AKT signaling pathway.

BACKGROUND: The incidence rate of acute pancreatitis (AP), which is a pathophysiological process with complex etiology, is increasing globally. miR-125b-5p, a bidirectional regulatory miRNA, is speculated to exhibit anti-tumor activity. However, exosome-derived miR-125b-5p in AP has not been reported. AIM: To elucidate the molecular mechanism of exosome-derived miR-125b-5p promoting AP exacerbation from the perspective of the interaction between immune cells and acinar cells. METHODS: Exosomes derived from AR42J cells were isolated and extracted in active and inactive states by an exosome extraction kit, and were verified via transmission electron microscopy, nanoparticle tracking analysis, and western blotting. RNA sequencing assay technology was used to screen differentially expressed miRNAs in active and inactive AR42J cell lines, and bioinformatics analysis was used to predict downstream target genes of miR-125b-5p. The expression level of miR-125b-5p and insulin-like growth factor 2 (IGF2) in the activated AR42J cell line and AP pancreatic tissue were detected by quantitative real-time polymerase chain reaction and western blots. The changes in the pancreatic inflammatory response in a rat AP model were detected by histopathological methods. Western Blot was used to detect the expression of IGF2, PI3K/AKT signaling pathway proteins, and apoptosis and necrosis related proteins. RESULTS: miR-125b-5p expression was upregulated in the activated AR42J cell line and AP pancreatic tissue, while that of IGF2 was downregulated. In vitro experiments confirmed that miR-125b-5p could promote the death of activated AR42J cells by inducing cell cycle arrest and apoptosis. In addition, miR-125b-5p was found to act on macrophages to promote M1 type polarization and inhibit M2 type polarization, resulting in a massive release of inflammatory factors and reactive oxygen species accumulation. Further research found that miR-125b-5p could inhibit the expression of IGF2 in the PI3K/AKT signaling pathway. Additionally, in vivo experiments revealed that miR-125b-5p can promote the progression of AP in a rat model. CONCLUSION: miR-125b-5p acts on IGF2 in the PI3K/AKT signaling pathway and promotes M1 type polarization and inhibits M2 type polarization of macrophage by inhibiting IGF2 expression, resulting in a large release of pro-inflammatory factors and an inflammatory cascade amplification effect, thus aggravating AP.

"One-step" approach versus "Step-up" approach minimally invasive treatment for infected pancreatic necrosis: a study protocol for a single-center, prospective, randomized controlled trial.

BACKGROUND: Currently, the minimally invasive "Step-up" surgical strategy is still the main treatment for infected pancreatic necrosis (IPN). However, indiscriminate implementation of the "Step-up" strategy can lead to increased numbers of operations and prolonged hospital stay. The "Step-up" approach is not appropriate for some patients due to unavailabilty of a safe puncture path. Therefore, we developed the "One-step" surgical approach to treat IPN, which is safety. However, there is still a lack of comparison of the short and long-term efficacy between the "One-step" and "Step-up" approach. Consequently, we are conducting this clinical trial to provide a reference for IPN treatment. METHODS: This is an ongoing, single-center, randomized controlled trial of patients with IPN. The total sample size required for the trial (May 2021-December 2023) is approximately 128 patients. Patients will be randomly assigned to either an experimental group (One-step) or a control group (Step-up) at a ratio of 1:1 using the block randomization method. We used the case report forms and electronic data capture systems to obtain demographic information, preoperative laboratory examination, auxiliary examination results, surgery data, postoperative recovery outcomes, and follow-up outcomes. The patients will be followed up for 2 years after surgery. The primary endpoint is a composite endpoint, consisting of mortality and severe complications. The secondary endpoints include the incidence of organ dysfunction, the number of surgical procedures, mortality (the incidence of death in hospital and deaths within 30 days of discharge), hospital stay, intensive care unit stay, hospitalization costs, perioperative inflammatory marker changes, and short-and long-term complications. DISCUSSION: Compared with the "Step-up," the "One-step" minimally invasive surgery can significantly reduce the number of operations, reduce the length of hospital stay and hospitalization costs without increasing the incidence of composite endpoint events, and has better short- and long-term efficacy and safety. Additionally, there was no statistically significant difference in perioperative complications and mortality between "Step-up" and "One-step". This study will assist with the formulation of an effective and scientific "One-step" minimally invasive treatment strategy for IPN, and an understanding of this technique will facilitate clinical decision-making for IPN. Trial Registration ChiCTR2100044348. Trial status: Ongoing.

Thromboxane A2 receptor contributes to the activation of rat pancreatic stellate cells induced by 8-epi-prostaglandin F2α.

BACKGROUND: Pancreatic stellate cells (PSCs) activation plays a critical role in the development of chronic pancreatitis. Previous studies confirmed that thromboxane A2 receptor (TxA2r) was overexpressed in activated PSCs in rats. The purpose of this study was to investigate the role of TxA2r in the activation of PSCs induced by 8-epi-prostaglandin F2α (8-epi-PGF2α). METHODS: TxA2r expression in both quiescent and activated PSCs was detected by immunocytochemistry and immunoblot assay. Isolated PSCs were treated with 8-epi-PGF2α (10, 10, 10 mol/L) for 48 h, and SQ29548 (10, 10, and 10 mol/L), a TxA2r-specific antagonist for 48 h, respectively, to identify the drug concentration with the best biological effect and the least cytotoxicity. Then isolated PSCs were treated with SQ29548 (10 mol/L) for 2 h, followed by 10 mol/L 8-epi-PGF2α for 48 h. Real-time polymerase chain reaction was performed to detect the messenger RNA (mRNA) levels of α-smooth muscle actin (α-SMA) and collagen I. Comparisons between the groups were performed using Student's t test. RESULTS: TxA2r was up-regulated in activated PSCs in vitro compared with quiescent PSCs (all P < 0.001). Compared with the control group, different concentrations of 8-epi-PGF2α significantly increased mRNA levels of α-SMA (10 mol/L: 2.23 ±â€Š0.18 vs. 1.00 ±â€Š0.07, t = 10.70, P < 0.001; 10 mol/L: 2.91 ±â€Š0.29 vs. 1.01 ±â€Š0.08, t = 10.83, P < 0.001; 10 mol/L, 1.67 ±â€Š0.07 vs. 1.00 ±â€Š0.08, t = 11.40, P < 0.001) and collagen I (10 mol/L: 2.68 ±â€Š0.09 vs. 1.00 ±â€Š0.07, t = 24.94, P < 0.001; 10 mol/L: 2.12 ±â€Š0.29 vs. 1.01 ±â€Š0.12, t = 6.08, P < 0.001; 10 mol/L: 1.46 ±â€Š0.15 vs. 1.00 ±â€Š0.05, t = 4.93, P = 0.008). However, different concentrations of SQ29548 all significantly reduced the expression of collagen I (10 mol/L: 0.55 ±â€Š0.07 vs. 1.00 ±â€Š0.07, t = 10.47, P < 0.001; 10 mol/L: 0.56 ±â€Š0.10 vs. 1.00 ±â€Š0.07, t = 6.185, P < 0.001; 10 mol/L: 0.27 ±â€Š0.04 vs. 1.00 ±â€Š0.07, t = 15.41, P < 0.001) and α-SMA (10 mol/L: 0.06 ±â€Š0.01 vs. 1.00 ±â€Š0.11, t = 15.17, P < 0.001; 10 mol/L: 0.28 ±â€Š0.03 vs. 1.00 ±â€Š0.11, t = 11.29, P < 0.001; 10 mol/L: 0.14 ±â€Š0.04 vs. 1.00 ±â€Š0.11, t = 12.86, P < 0.001). After being treated with SQ29548 (10 mol/L) and then 8-epi-PGF2α (10 mol/L), the mRNA levels of α-SMA (0.20 ±â€Š0.08 vs. 1.00 ±â€Š0.00, t = 17.46, P < 0.001) and collagen I (0.69 ±â€Š0.13 vs. 1.00 ±â€Š0.00, t = 4.20, P = 0.014) in PSCs were significantly lower than those of the control group. CONCLUSIONS: The results show that 8-epi-PGF2α promoted PSCs activation, while SQ29548 inhibited PSCs activation induced by 8-epi-PGF2α. The result indicated that TxA2r plays an important role during PSC activation and collagen synthesis induced by 8-epi-PGF2αin vitro. This receptor may provide a potential target for more effective antioxidant therapy for pancreatic fibrosis.

Mst1 overexpression combined with Yap knockdown augments thyroid carcinoma apoptosis via promoting MIEF1-related mitochondrial fission and activating the JNK pathway.

BACKGROUND: Cancer cell viability is strongly modulated by the Hippo pathway, which includes mammalian STE20-like protein kinase 1 (Mst1) and yes-associated protein (Yap). Although the roles of Mst1 and Yap in thyroid carcinoma cell death have been fully addressed, no study has determined whether differential modification of Mst1 and Yap could further suppress thyroid carcinoma progression. The aim of our study was to explore the antiapoptotic effects exerted by combined Mst1 overexpression and Yap knockdown in thyroid carcinoma MDA-T32 cells in vitro. METHODS: Mst1 adenovirus and Yap shRNA were transfected into MDA-T32 cells to overexpress Mst1 and inhibit Yap, respectively. Cell viability and death were determined via an MTT assay, a TUNEL assay and western blotting. Mitochondrial function, mitochondrial fission and pathway studies were performed via western blotting and immunofluorescence. RESULTS: The results of our study showed that combined Mst1 overexpression and Yap knockdown further augmented MDA-T32 cell death by mediating mitochondrial damage. In addition, cancer cell migration and proliferation were suppressed by combined Mst1 overexpression and Yap knockdown. At the molecular level, mitochondrial membrane potential, ATP production, respiratory function, and caspase-9-related apoptosis were activated by combined Mst1 overexpression and Yap knockdown. Further, we found that fatal mitochondrial fission was augmented by combined Mst1 overexpression and Yap knockdown in a manner dependent on the JNK-MIEF1 pathway. Inhibition of JNK-MIEF1 pathway activity abolished the proapoptotic effects exerted by Mst1/Yap on MDA-T32 cells. CONCLUSIONS: Taken together, our data suggest that Mst1 activation and Yap inhibition coordinate to augment thyroid cancer cell death by controlling the JNK-MIEF1-mitochondria pathway, suggesting that differential regulation of the core Hippo pathway components is potentially a novel therapeutic tool for the treatment of thyroid cancer.

Upregulation of the checkpoint protein CHFR is associated with tumor suppression in pancreatic cancers.

The checkpoint with forkhead-associated (FHA) domain and RING-finger (CHFR) protein was identified as a cell cycle checkpoint protein and E3 ubiquitin ligase. In the present study, the potential functions of CHFR in pancreatic cancer were investigated. CHFR expression was measured in five pancreatic cancer cell lines by reverse transcription- quantitative polymerase chain reaction and western blotting. Capan-1 cells stably expressing CHFR were established by lentiviral vector transfection. Cell proliferation was assessed using Cell Counting Kit-8, and cell migration/invasion assay was determined using Transwell assays. Cell cycle and apoptosis induced by gemcitabine or docetaxel were evaluated using flow cytometry. CHFR expression levels were also evaluated in pancreatic ductal adenocarcinoma (PDAC) tumor samples as well as adjacent non-tumor tissues by immunohistochemistry. The significance of CHFR expression was determined, with respect to clinicopathological features and overall survival. Overexpression of CHFR in Capan-1 cells led to a decreased proliferative rate and reduced cell migration and invasion abilities. Results also indicated an increase in G1 phase cells in Capan-1 cells overexpressing CHFR. Docetaxel-induced apoptosis was inhibited in Capan-1 cells with CHFR-overexpression. A reduction in CHFR expression was detected in 51.9% of patients with PDAC, which significantly correlated with later T-stage. The results show CHFR functions as a tumor suppressor in pancreatic cancer, suggests its potential role in controlling the cell cycle of pancreatic cancer cells; however, CHFR overexpression is not a favorable factor in apoptosis induced by docetaxel.

Post-translational modifications of α-synuclein contribute to neurodegeneration in the colon of elderly individuals.

Synucleinopathies and abnormalities in the nerves of the enteric nervous system are hypothesized to be involved in age-associated motility disorders. The aim of the present study was to investigate the expression of various antigens, including α­synuclein (Syn) and its post­translational modified forms, in the human colon at various ages. In addition, the study aimed to correlate the expression of Syn with neurodegeneration. Immunohistochemistry was used to detect the expression of neurofilament (NF), Syn, as well as its nitrated (N) form in the healthy colonic tissue of 12 young (34.08±5.12 years), 10 middle­aged (51.80±3.52 years), and 11 elderly (75.82±7.70 years) individuals. To the best of our knowledge, the current study is the first to demonstrate the presence of N­Syn in the colonic tissue. N­Syn was identified in the upper layer of the mucosa and submucosa layer. Furthermore, Syn (wild­type) was present in the mucosa and submucosa. The number of NF­positive neurons in the submucosal layer declined significantly with age (P<0.01). In addition, Syn and N­Syn significantly increased during aging (P<0.01). Furthermore, a negative correlation was identified between neuron number and synucleinopathies, indicating the abnormal accumulation of both wild-type Syn and N­Syn in the mucosa, submucosa, muscle layer and myenteric plexus. The present study demonstrates that the Syn pathology may be linked to colic neuronal degeneration during normal aging, and this link may cause functional deficits.

Silencing pancreatic adenocarcinoma upregulated factor (PAUF) increases the sensitivity of pancreatic cancer cells to gemcitabine.

Pancreatic adenocarcinoma upregulated factor (PAUF) is a new oncogene that activates signaling pathways that play a critical role in resistance to gemcitabine. We thus speculated that PAUF also plays a role in resistance to gemcitabine of pancreatic cancer cells. We established BxPC-3 cell lines with stable PAUF knockdown (BxPC-3_shPAUF) and controls (BxPC-3_shCtrl) and evaluated sensitivity to gemcitabine in vitro by MTT and flow cytometry. We established a xenograft model of human pancreatic cancer to examine PAUF function in gemcitabine resistance in vivo. Gene chip microarrays were performed to identify differentially expressed genes in BxPC-3_shPAUF and BxPC-3_shCtrl cells. Silencing PAUF increased the sensitivity of BxPC-3 cells to gemcitabine in vitro and in vivo. PAUF-knockdown BxPC-3 cell lines treated with gemcitabine showed increased proliferation inhibition and apoptosis compared with controls. Gemcitabine exhibited a more pronounced effect on reduction of BxPC-3_shPAUF tumors than BxPC-3_shCtrl tumors. Terminal deoxynucleotidyl transferase dUTP Nick-End Labeling (TUNEL) assays confirmed a significantly higher apoptotic rate of BXPC-3_shPAUF tumors compared with BXPC-3_shCtrl tumors. Gene array showed that PAUF function in gemcitabine sensitivity might involve MRP2, MRP3, MDR1, PIK3R1, and NFkB2 genes. PAUF could be considered as a key molecular target for sensitizing pancreatic cancer cells to gemcitabine.

Indoleamine 2,3-dioxygenase is upregulated in the brain of rats with acute pancreatitis.

BACKGROUND: Acute pancreatitis (AP) has an effect on both inflammatory/autoimmune processes and psychological states, but the pathophysiological causes of pancreatic encephalopathy in the brain are unclear. We hypothesized that the peripheral immune/inflammatory response during AP can affect indolamine 2,3-dioxygenase (IDO) expression and serotonin content in the brain. METHODS: About 210 male Sprague Dawley rats were randomly divided into five groups: control (0 h) and 6 h, 24 h, 48 h and 72 h experimental groups. Acute pancreatitis was induced by an injection of a sodium taurocholate solution via a cannulated bile-pancreatic duct. We measured the plasma TNF-α and IL-6 levels; serotonin, 5-HIAA and the protein concentration levels of IDO and monoamine oxidase A (MAO-A) were evaluated in the striatum, hippocampus and left prefrontal cortex. RESULTS: The IL-6 and the TNF-α levels increased in the 24 h, 48 h and 72 h groups. The IDO concentrations of both the 72 h group in the hippocampus and 48 h, 72 h groups in the prefrontal cortex increased; in the corpus striatum, the IDO concentrations fluctuated without statistical significance. The MAO-A protein concentration of the 6 h and 24 h groups decreased in the striatum, hippocampus and prefrontal cortex. There were no statistically significant differences found in the serotonin and 5-HIAA concentrations. CONCLUSIONS: During the process of AP, cytokines, such as IL-6 and TNF-α, may play a role in activation of neuronal pathways utilizing the metabolic enzyme IDO, which may play an important role in determining the mental symptomatology accompanying AP.

HES 1 is essential for chemoresistance induced by stellate cells and is associated with poor prognosis in pancreatic cancer.

The role of pancreatic stellate cells (PSCs) has been established in many studies. However, the potential mechanism for the chemoresistance induced by PSCs has not been fully elucidated. In the present study, human pancreatic cancer cell lines were directly or indirectly co-cultured with PSCs. The inhibition rate and IC50 values were assessed to determine the ability of chemoresistance. RT-PCR and western blot analysis were used to evaluate Hes 1 and Jagged 1 expression before and after co-culture with PSCs. To determine the relationship between Hes 1 expression and survival in pancreatic cancer patients, Kaplan-Meier survival analysis was performed. PSCs promoted the expression of Hes 1 in both PANC-1 and BxPC-3 cell lines and induced chemoresistance to gemcitabine. A Notch signaling pathway inhibitor (L1790) and Hes 1 siRNA reversed the chemoresistance induced by PSCs. In 72 resected pancreatic cancer patients, high Hes 1 expression was observed in 34 patients with shorter overall and progression-free survival times. In conclusion, Hes 1 is essential for chemoresistance induced by PSCs and is associated with poor prognosis in pancreatic cancer patients. Therapy targeting the Notch signaling pathway may reverse chemoresistance and improve survival in patients with pancreatic cancer.

Phenotypic characteristics of nasal mast cells in a mouse model of allergic rhinitis.

BACKGROUND: Mast cells (MCs) in the nasal respiratory mucosa (NRM) play a triggering role in the pathogenesis of allergic rhinitis (AR). Recent research evidence in mouse models of AR suggests an underlying MC-related allergic response in mouse nasal olfactory mucosa (NOM). OBJECTIVE: We sought to investigate the phenotypic characteristics of nasal MCs in a mouse model of AR. METHODS: By MC-specific staining and immunohistochemistry, we analyzed the subset, protease and IgE-binding phenotypes of nasal MCs in ovalbumin (OVA)-sensitized unchallenged and challenged mice. RESULTS: In OVA-sensitized challenged mice, increased serum OVA-specific IgE levels (p < 0.001) and eosinophil infiltration confirmed AR induction. In addition to constitutive connective tissue MCs, mucosal MCs were induced in NRM and NOM of OVA-sensitized challenged mice. Connective tissue MCs and mucosal MCs in mouse NRM and NOM were positive for mouse MC protease-1, -4, -5, -6, -7 and carboxypeptidase-A3. In line with MCs in NRM, there were increased numbers (p = 0.019) and proportions (p = 0.027) of MCs with surface-bound IgE in NOM of OVA-sensitized challenged mice. CONCLUSION: In the setting of AR, MCs in mouse NOM exhibit the same subset, protease and IgE-binding phenotypes as MCs in mouse NRM.

Histological and mechanical properties of autologous living tissue biotubes.

The aim of this study was to explore and evaluate biotubes consisting of autologous tissues. The biotubes were prepared by intra-abdominally embedding silicon rods as moulds. The specimens were analyzed by mechanical tests, histological observation and superficial study. The intra-abdominal implantation of the silicone tubes readily stimulated the development of the biotubes. The biotubes consisted of collagen-rich extracellular matrices. Myofibroblasts appeared as elongated cells with circumferential or longitudinal orientations. Subsequent to one month of embedding, the thickness of the tube wall was 70-250 µm. The burst strength was 1100±187 mmHg and the suturability was excellent. Biotubes that have the ability to be widely variable in their shapes are composed of autologous cells and glomerular extracellular matrices. Biotubes are ideal grafts for tissue engineering as they are able to avoid immunological rejection and are of sufficient mechanical strength.

[The role of oxide stress during the pathogenesis of chronic pancreatic injuries induced by chronic high-fat diets in rat].

OBJECTIVE: To provide more detailed information on the roles of lipid peroxidation in the pathogenesis of chronic pancreatic injuries in a pre-clinical rat model. METHODS: Totally 72 rats were divided into 6 groups (12 in each group) Rats in 5 experimental groups (n = 12) were fed with a high-fat diet (1% cholesterol, 10% lard, 0.3% sodium tauroglycocholate, 87.3% standard rodent chow as the control group) for 2, 4, 6, 10 and 16 weeks, respectively. Morphological studies in the pancreas tissue samples from rats were investigated by using various histological methods. Pancreatic stellate cells (PSCs) were identified by immunohistochemical staining for Desmin and α-smooth muscle actin (α-SMA). The expression of the lipid peroxidation was detected by immunostaining for 4-hydroxy-2-nonenal (4-HNE) and thromboxane A2 receptor (TxA2r). The co-localization of α-SMA and 4-HNE or α-SMA and TxA2r in PSCs was also analyzed in this study. RESULTS: Pancreatic cells with positive staining for Desmin and α-SMA in HFD rats were distributed in a more extensive way when compared to that in the control group. The levels of pancreatic 4-HNE and TxA2r were increased in rats from HFD groups significantly. The co-localization of 4-HNE and TxA2r were also found within activated PSCs in both of groups. CONCLUSION: The results showed that a chronic HFD feeding may increase the lipid peroxidation process and collagen synthesis through a critical signaling pathway of activated PSCs following pancreatic injuries in rats.

Contribution of different mechanisms to pancreatic beta-cell hyper-secretion in non-obese diabetic (NOD) mice during pre-diabetes.

The development of insulin-dependent diabetes mellitus (IDDM) results from the selective destruction of pancreatic beta-cells. Both humans and spontaneous models of IDDM, such as NOD mice, have an extended pre-diabetic stage. Dynamic changes in beta-cell mass and function during pre-diabetes, such as insulin hyper-secretion, remain largely unknown. In this paper, we evaluated pre-diabetic female NOD mice at different ages (6, 10, and 14 weeks old) to illustrate alterations in beta-cell mass and function as disease progressed. We found an increase in beta-cell mass in 6-week-old NOD mice that may account for improved glucose tolerance in these mice. As NOD mice aged, beta-cell mass progressively reduced with increasing insulitis. In parallel, secretory ability of individual beta-cells was enhanced due to an increase in the size of slowly releasable pool (SRP) of vesicles. Moreover, expression of both SERCA2 and SERCA3 genes were progressively down-regulated, which facilitated depolarization-evoked secretion by prolonging Ca(2+) elevation upon glucose stimulation. In summary, we propose that different mechanisms contribute to the insulin hyper-secretion at different ages of pre-diabetic NOD mice, which may provide some new ideas concerning the progression and management of type I diabetes.

Increased expression of α-synuclein in aged human brain associated with neuromelanin accumulation.

Although the increased prevalence of Parkinson's disease (PD) with aging suggests that aging processes predispose dopamine neurons to degeneration, the mechanism involved remains unknown. Dopamine neurons contain significant amounts of neuromelanin, and the amount of neuromelanin increases with aging. In the present study, age-related changes in the number of nigral neurons expressing neuromelanin (NM), α-synuclein, and tyrosine hydroxylase (TH) were stereologically analyzed in the postmortem brains of 28 healthy humans with an age range of 17-84 years. Stereological counting of NM content, α-synuclein content, and TH immunoreactivity revealed significant accumulation of NM and α-synuclein in neurons during the aging process. In cells containing a large amount of NM, α-synuclein-immunoreactive cells in aged individuals outnumbered those of younger individuals. In non-NM cells, the α-synuclein expression profile was similar across age groups. Furthermore, TH-immunoreactive neurons decreased significantly with aging, which was associated with accumulation of NM and α-synuclein. Our results suggest that age related accumulation of NM might induce α-synuclein over-expression and thereby make dopamine neurons more vulnerable to injuries.

Preliminary research on the pathological role of cathepsin-B in subcutaneous heteroplastic pancreatic carcinoma in nude mice.

BACKGROUND: Cathespin-B (cath-B) is an important proteolytic enzyme involved in the disease course of invasion in many types of cancer. Cath-B expression in subcutaneous heteroplastic pancreatic carcinoma in nude mice has not been studied. We investigated the role of cath-B in a model of heteroplastic pancreatic carcinoma in BALB/c nude mice. METHODS: Thirty-two six-week-old female BALB/c nude mice were equally divided into four groups. PANC-1 cells were inoculated subcutaneously in the left axillary region. Besides volume, weight of subcutaneous tumor, and change in body weight, cath-B expression in each group was measured by immunohistochemical staining, PCR and Western blotting. Its relationship to microvessel density (MVD), CD44v6, and placenta growth factor (PLGF) was also examined. CA-074Me, a specific inhibitor of cath-B, was injected intraperitoneally (i.p.) at different stages of tumor growth in group B and C. Gemcitabine (GEM), was also injected (i.p.) in group D to compare anti-tumor efficacy with CA-074Me. RESULTS: Expression of cath-B at different levels was related to tumor growth, MVD, and PLGF expression. In group A (control group), cath-B expression was enhanced more than that seen in other groups. CA-074Me clearly inhibited cath-B expression and tumor growth in group B. There was no difference between group C and D with respect to anti-tumor effect. CONCLUSIONS: Cath-B correlates with the growth and angiogenesis of tumors, but not with the adhesion induced by CD44v6. CA-074Me clearly inhibited cath-B expression and demonstrated an anti-neoplastic and anti-angiogenesis effect.

Chronic high-fat diets induce oxide injuries and fibrogenesis of pancreatic cells in rats.

OBJECTIVES: The mechanism of pancreatic damages induced by chronic high-fat diets (HFDs) remains unknown. The current study was to detect the involvement of free fatty acids (FFAs) and lipid peroxidation in pancreatic injuries in rats induced by a long-term HFD. METHODS: Rats of HFD groups (n = 12) were fed with an HFD for 2, 4, 6, 10, and 18 weeks, respectively. Pancreatic malondialdehyde content and the concentration of FFA were measured. Histopathologic changes were observed by Sirius red staining for fibrosis and immunostaining of the pancreatic stellate cells for desmin, alpha-smooth muscle actin, platelet-derived growth factor receptor type beta, and transforming growth factor beta1. RESULTS: Pancreatic malondialdehyde content, the number of desmin and alpha-SMA positive cells significantly increased in all the HFD groups (P < 0.05). The levels of pancreatic FFA, platelet-derived growth factor receptor type beta, and transforming growth factor beta1 increased in rats of 2-, 4-, and 6-week HFD groups (P < 0.05). These enhancements were accompanied with sequential histopathology alterations that resulted from acute inflammatory response in the early stages of secondary pancreatic fibrosis. CONCLUSIONS: The results indicate that chronic HFD increased pancreatic FFA and lipid peroxidation associated with pancreatic injuries and collagen synthesis by activated pancreatic stellate cells in rats.

Growth suppression of MCF-7 cancer cell-derived xenografts in nude mice by caveolin-1.

Caveolin-1 is an essential structural constituent of caveolae membrane domains that has been implicated in mitogenic signaling and oncogenesis. However, the exact functional role of caveolin-1 still remains controversial. In this report, utilizing MCF-7 human breast adenocarcinoma cells stably transfected with caveolin-1 (MCF-7/cav-1 cells), we demonstrate that caveolin-1 expression dramatically inhibits invasion and migration of these cells. Importantly, in vivo experiments employing xenograft tumor models demonstrated that expression of caveolin-1 results in significant growth inhibition of breast tumors. Moreover, a dramatic delay in tumor progression was observed in MCF-7/cav-1 cells as compared with MCF-7 cells. Histological analysis of tumor sections demonstrated a marked decrease in the percentage of proliferating tumor cells (Ki-67 assay) along with an increase in apoptotic tumor cells (TUNEL assay) in MCF-7/cav-1-treated animals. Our current findings provide for the first time in vivo evidence that caveolin-1 can indeed function as a tumor suppressor in human breast adenocarcinoma derived from MCF-7 cells rather than as a tumor promoter.