Roles Played by DOCK11, a Guanine Nucleotide Exchange Factor, in HBV Entry and Persistence in Hepatocytes.

HBV infection is challenging to cure due to the persistence of viral covalently closed circular viral DNA (cccDNA). The dedicator of cytokinesis 11 (DOCK11) is recognized as a guanine nucleotide exchange factor (GEF) for CDC42 that has been reported to be required for HBV persistence. DOCK11 is expressed in both the cytoplasm and nucleus of human hepatocytes and is functionally associated with retrograde trafficking proteins Arf-GAP with GTPase domain, ankyrin repeat, and pleckstrin homology domain-containing protein 2 (AGAP2), and ADP-ribosylation factor 1 (ARF1), together with the HBV capsid, in the trans-Golgi network (TGN). This opens an alternative retrograde trafficking route for HBV from early endosomes (EEs) to the TGN and then to the endoplasmic reticulum (ER), thereby avoiding lysosomal degradation. DOCK11 also facilitates the association of cccDNA with H3K4me3 and RNA Pol II for activating cccDNA transcription. In addition, DOCK11 plays a crucial role in the host DNA repair system, being essential for cccDNA synthesis. This function can be inhibited by 10M-D42AN, a novel DOCK11-binding peptide, leading to the suppression of HBV replication both in vitro and in vivo. Treatment with a combination of 10M-D42AN and entecavir may represent a promising therapeutic strategy for patients with chronic hepatitis B (CHB). Consequently, DOCK11 may be seen as a potential candidate molecule in the development of molecularly targeted drugs against CHB.

BMP9-ID1 Pathway Attenuates N6-Methyladenosine Levels of CyclinD1 to Promote Cell Proliferation in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a highly lethal malignant neoplasm, and the involvement of bone morphogenetic protein 9 (BMP9) has been implicated in the pathogenesis of liver diseases and HCC. Our goal was to investigate the role of BMP9 signaling in regulating N6-methyladenosine (m6A) methylation and cell cycle progression, and evaluate the therapeutic potential of BMP receptor inhibitors for HCC treatment. We observed that elevated levels of BMP9 expression in tumor tissues or serum samples from HCC patients were associated with a poorer prognosis. Through in vitro experiments utilizing the m6A dot blotting assay, we ascertained that BMP9 reduced the global RNA m6A methylation level in Huh7 and Hep3B cells, thereby facilitating their cell cycle progression. This effect was mediated by an increase in the expression of the inhibitor of DNA-binding protein 1 (ID1). Additionally, using methylated RNA immunoprecipitation qPCR(MeRIP-qPCR), we showed that the BMP9-ID1 pathway promoted CyclinD1 expression by decreasing the m6A methylation level in the 5' UTR of mRNA. This occurred through the upregulation of the fat mass and obesity-associated protein (FTO) in Huh7 and Hep3B cells. In our in vivo mouse xenograft models, we demonstrated that blocking the BMP receptor with LDN-212854 effectively suppressed HCC growth and induced global RNA m6A methylation. Overall, our findings indicate that the BMP9-ID1 pathway promotes HCC cell proliferation by down-regulating the m6A methylation level in the 5' UTR of CyclinD1 mRNA. Targeting the BMP9-ID1 pathway holds promise as a potential therapeutic strategy for treating HCC.

Effect of wearable chair on gait, balance, and discomfort of new users during level walking with anterior loads.

INTRODUCTION: Walking with anterior loads is common in industrial scenarios, but as exoskeletons are increasingly used in work environments to alleviate musculoskeletal disorders (MSDs), this new "human-robot" system composed of the human body and exoskeleton may be associated with new risks and harm that warrant further investigation. Therefore, this study will discuss the effect of a wearable chair on the gait, balance, and discomfort of new users with different weights of anterior loads during level walking. METHOD: Twenty-two healthy subjects (sex balanced) participated in the experiment. Each exposure comprised one of two exoskeleton states (with/without) and four load conditions: No carried load, carrying an empty box (0.3 kg), 5%Body Weight (BW), and 10%BW. The order of exoskeleton states and load conditions was randomly assigned. Using an eight-camera motion capture system to record the entire movement. And the subjective discomfort and perceived balance after each exposure were recorded on an 11-point numeric rating scale, respectively. Using SPSS 26.0 software (IBM Inc., Chicago) to conduct statistical analyses. RESULTS: Level walking with a wearable chair in different load conditions significantly affected gait parameters (like cadence) and gait balance. The perceived balance decreased with the exoskeleton, consistent with objective results. For subjective discomfort, wearing the exoskeleton significantly impacted global discomfort. Also, it increased the local discomfort of the shoulders, waist, thighs, shanks, and feet/ankles. CONCLUSIONS: For new users, the risk of losing balance or falling may be increased when wearing an exoskeleton for non-target task behaviors (level walking/anterior load), and caution is recommended when the anterior load exceeds 5% BW. PRACTICAL APPLICATION: The proposed strategy for assessing human gait, balance, and discomfort in wearable chairs may be applied during the iterative design of the product. These controls will help develop training programs and implementation guidelines for this exoskeleton type.

Functional involvement of endothelial lipase in hepatitis B virus infection.

BACKGROUND: HBV infection causes chronic liver disease and leads to the development of HCC. To identify host factors that support the HBV life cycle, we previously established the HC1 cell line that maintains HBV infection and identified host genes required for HBV persistence. METHODS: The present study focused on endothelial lipase (LIPG), which binds to heparan sulfate proteoglycans (HSPGs) in the cell membrane. RESULTS: We found HBV infection was impaired in humanized liver chimeric mouse-derived hepatocytes that were transduced with lentivirus expressing short hairpin RNA against LIPG. Long-term suppression of LIPG combined with entecavir further suppressed HBV replication. LIPG was shown to be involved in HBV attachment to the cell surface by using 2 sodium taurocholate cotransporting peptide (NTCP)-expressing cell lines, and the direct interaction of LIPG and HBV large surface protein was revealed. Heparin and heparinase almost completely suppressed the LIPG-induced increase of HBV attachment, indicating that LIPG accelerated HBV attachment to HSPGs followed by HBV entry through NTCP. Surprisingly, the attachment of a fluorescently labeled NTCP-binding preS1 probe to NTCP-expressing cells was not impaired by heparin, suggesting the HSPG-independent attachment of the preS1 probe to NTCP. Interestingly, attachment of the preS1 probe was severely impaired in LIPG knockdown or knockout cells. Inhibitors of the lipase activity of LIPG similarly impaired the attachment of the preS1 probe to NTCP-expressing cells. CONCLUSIONS: LIPG participates in HBV infection by upregulating HBV attachment to the cell membrane by means of 2 possible mechanisms: increasing HBV attachment to HSPGs or facilitating HSPG-dependent or HSPG-independent HBV attachment to NTCP by its lipase activity.

Super-Resolution Microscopy Analysis of Hepatitis B Viral cccDNA and Host Factors.

Infection with hepatitis B virus (HBV) cannot be cured completely because of the persistence of covalently closed circular DNA (cccDNA). We previously found that the host gene dedicator of cytokinesis 11 (DOCK11) was required for HBV persistence. In this study, we further investigated the mechanism that links DOCK11 to other host genes in the regulation of cccDNA transcription. cccDNA levels were determined by quantitative real-time polymerase chain reaction (qPCR) and fluorescence in situ hybridization (FISH) in stable HBV-producing cell lines and HBV-infected PXB-cells®. Interactions between DOCK11 and other host genes were identified by super-resolution microscopy, immunoblotting, and chromatin immunoprecipitation. FISH facilitated the subcellular localization of key HBV nucleic acids. Interestingly, although DOCK11 partially colocalized with histone proteins, such as H3K4me3 and H3K27me3, and nonhistone proteins, such as RNA Pol II, it played limited roles in histone modification and RNA transcription. DOCK11 was functionally involved in regulating the subnuclear distribution of host factors and/or cccDNA, resulting in an increase in cccDNA closely located to H3K4me3 and RNA Pol II for activating cccDNA transcription. Thus, it was suggested that the association of cccDNA-bound Pol II and H3K4me3 required the assistance of DOCK11. DOCK11 facilitated the association of cccDNA with H3K4me3 and RNA Pol II.

Emerging evidence on the effects of plant-derived microRNAs in colorectal cancer: a review.

Food nutrition and human health are still interesting international issues. Early detection, risk assessment and diet are vital to mitigate the load of intestinal diseases and enhance the quality of life. Plant-derived microRNAs could be transferred to mammalian organisms by cross-kingdom regulation which adjusts relevant target genes for their participation in the process of carcinogenesis. But the mechanism of plant-derived microRNAs in colorectal cancer is still unclear. This review aims to summarize the current pathways of plant-derived microRNAs in colorectal cancer including intestinal bacteria, the tumor microenvironment, plant active substances and protein, discuss the direct or indirect effects of plant-derived microRNAs on the occurrence and/or progression of colorectal cancer and explain why plant-derived microRNAs can be used as a potential anti-cancer agent. Moreover, the drawbacks of plant-derived microRNAs are also discussed in terms of both edible plants and synthetic delivery vectors for RNAi interference technology for human disease treatment. This review will provide a potential way for plant-derived microRNAs to target colorectal cancer.

Hepatitis B Virus Utilizes a Retrograde Trafficking Route via the Trans-Golgi Network to Avoid Lysosomal Degradation.

BACKGROUND & AIMS: Hepatitis B virus (HBV) infection is difficult to cure owing to the persistence of covalently closed circular viral DNA (cccDNA). We performed single-cell transcriptome analysis of newly established HBV-positive and HBV-negative hepatocellular carcinoma cell lines and found that dedicator of cytokinesis 11 (DOCK11) was crucially involved in HBV persistence. However, the roles of DOCK11 in the HBV lifecycle have not been clarified. METHODS: The cccDNA levels were measured by Southern blotting and real-time detection polymerase chain reaction in various hepatocytes including PXB cells by using an HBV-infected model. The retrograde trafficking route of HBV capsid was investigated by super-resolution microscopy, proximity ligation assay, and time-lapse analysis. The downstream molecules of DOCK11 and underlying mechanism were examined by liquid chromatography-tandem mass spectrometry, immunoblotting, and enzyme-linked immunosorbent assay. RESULTS: The cccDNA levels were strongly increased by DOCK11 overexpression and repressed by DOCK11 suppression. Interestingly, DOCK11 functionally associated with retrograde trafficking proteins in the trans-Golgi network (TGN), Arf-GAP with GTPase domain, ankyrin repeat, and pleckstrin homology domain-containing protein 2 (AGAP2), and ADP-ribosylation factor 1 (ARF1), together with HBV capsid, to open an alternative retrograde trafficking route for HBV from early endosomes (EEs) to the TGN and then to the endoplasmic reticulum (ER), thereby avoiding lysosomal degradation. Clinically, DOCK11 levels in liver biopsies from patients with chronic hepatitis B were significantly reduced by entecavir treatment, and this reduction correlated with HBV surface antigen levels. CONCLUSIONS: HBV uses a retrograde trafficking route via EEs-TGN-ER for infection that is facilitated by DOCK11 and serves to maintain cccDNA. Therefore, DOCK11 is a potential therapeutic target to prevent persistent HBV infection.

A single hepatitis B virus genome with a reporter allows the entire viral life cycle to be monitored in primary human hepatocytes.

For the development of antiviral agents to eliminate hepatitis B virus (HBV), it is essential to establish an HBV cell culture system that can easily monitor HBV infection. Here, we created a novel HBV infection monitoring system using a luminescent 11-amino acid reporter, the high-affinity subunit of nano-luciferase binary technology (HiBiT). The HiBiT-coding sequence was inserted at the N-terminus of preS1 in a 1.2-fold plasmid encoding a genotype C HBV genome. After transfection of HepG2 cells with this HiBiT-containing plasmid, the supernatant was used to prepare a recombinant cell culture-derived virus (HiBiT-HBVcc). Primary human hepatocytes (PXB) were inoculated with HiBiT-HBVcc. Following inoculation, intracellular and extracellular HiBiT activity and the levels of various HBV markers were determined. Reinfection of naive PXB cells with HiBiT-HBVcc prepared from HiBiT-HBVcc-infected PXB cells was analyzed. When PXB cells were infected with HiBiT-HBVcc at several titers, extracellular HiBiT activity was detected in a viral titer-dependent manner and was correlated with intracellular HiBiT activity. Inhibitors of HBV entry or replication suppressed extracellular HiBiT activity. Viral DNA, RNA, and proteins were detectable, including covalently closed circular DNA, by Southern blot analysis. The synthesis of relaxed-circular DNA from single-stranded DNA in HiBiT-HBV decreased to one third of that of wild-type HBV, and the infectivity of HiBiT-HBVcc decreased to one tenth of that of wild-type HBVcc. HiBiT-HBVcc prepared from PXB cells harboring HiBiT-HBV was able to infect naive PXB cells. Conclusions: Recombinant HiBiT-HBV can undergo the entire viral life cycle, thus facilitating high-throughput screening for HBV infection in vitro using supernatants. This system will be a powerful tool for developing antiviral agents.

Bilateral ureteral reimplantation in a patient with an intraperitoneal ectopic bipenis: A case report.

BACKGROUND: Diphallia is a highly uncommon congenital urogenital abnormality and a few connected reports have been published. However, no case of intraabdominal heterotopic diphallus has been documented to date. In the present study, we present a rare case of intraperitoneal ectopic bipenis. CASE SUMMARY: A 49-year-old man was hospitalized with the chief complaint of hydronephrosis of both kidneys, which was discovered three days earlier through regular physical examination performed using urological ultrasound without significant lumbar or abdominal pain or bladder irritation. Physical examination showed normal external penile development, bilateral testes located on the left side of the scrotum, and a fused epididymis. Urological plain and enhanced computed tomography suggested bilateral hydronephrosis, bilateral ureters opened to the left side of the bladder wall; an intrapelvic soft tissue shadow on the left side of the bladder was considered a germline malformation called bipenis (hidden penis in the abdominal cavity). Based on the urological plain and enhanced computed tomography results, a 49-year-old man was diagnosed with bipenis (one hidden in the abdominal cavity). Ectopic penile compression produced bilateral ureteral dilatation and hydronephrosis. The ectopic penis was amputated and partially removed during surgery, and bilateral ureteral replantation was successfully performed. At a 2-mo follow-up, the patient was very satisfied with the operation, there was no significant hydronephrosis in both kidneys, and urination and erectile function were normal. CONCLUSION: To our knowledge, this is the first report of diphallia with an intraperitoneal ectopic penis. Computed tomography or magnetic resonance imaging can be used to assess the associated internal anomalies before surgery. Postoperative pathological findings are the gold standard for the diagnosis.

Color brightness model and its imaging applications.

We have developed an empirical umbrella model for predicting the brightness of colors. It is based on a modified concept of the radiance factor. Instead of a single reference, i.e., white, for all colors, each color has its own reference color. Our model shows that, for near neutral colors, the boundary of the object-color solid accounts for most of the hue angles, except in the cyan-blue region, where the boundary has to be adjusted by experiments on color charts. We use an exponential function to extrapolate the umbrella to the colors of higher purity. The model is used to adjust the luminance of the Munsell colors to make them equally bright by compensating for the Helmholtz-Kohlrausch effect. It is also applied to real consumer images to reduce their brightness after boosting their color saturation. For both applications, the comparison images show that the model is quite effective.

[Mycoplasma genitalium and male urogenital diseases: An update].

Mycoplasma genitalium (MG) was first isolated by Tully from the urinary tract of the male patient with non-gonococcal urethritis (NGU) in 1981. MG is extremely difficult to be cultured and was rarely studied until the development and application of molecular biology technology. The research on MG in China is still in the primary stage. However, relevant studies abroad have found that it is an important pathogen causing human genitourinary tract infection and spreading worldwide. Male MG infection is reportedly related to NGU, prostatitis, epididymitis, balanoposthitis, male HIV infection, and male infertility. This review outlines the advances in the studies of MG in male urogenital diseases.

Auto white balance by surface reflection decomposition.

Auto white balance (AWB) is an important operation in color imaging applications. Most existing AWB algorithms rely on some physical features and statistical properties of natural scenes. However, the AWB algorithms using statistical properties are sensitive to the statistics of the scene contents. Therefore, it is highly desirable to find physical features that are more robust and relatively insensitive to scene contents. In this paper, we propose such physical features based on surface reflection decomposition. Light reflection from most object surfaces can be decomposed into a specular component and a diffuse component. Instead of trying to find the common axis of the color planes as in past algorithms, we estimate the illuminant chromaticity by searching through the light source candidates to find the one that will best cancel the specular components. We provide two formulations: the minimum projected area algorithm and the minimum total variation algorithm for estimation of the scene-illuminant chromaticity. Both show very favorable results compared with other published algorithms.

Pim-3 Regulates Stemness of Pancreatic Cancer Cells via Activating STAT3 Signaling Pathway.

Due to its aggressiveness and unusual resistance to conventional therapies, pancreatic cancer is a highly lethal gastrointestinal malignancy with poor prognosis. According to the cancer stem cell hypothesis, there exists a fraction of cancer cells, that is, cancer stem cells, responsible for tumor maintenance and therapeutic failure. Herein we investigated the involvement of proto-oncogene Pim-3 in driving the stemness properties in pancreatic cancer. Expression levels of several stemness-associated markers were examined in several pancreatic cancer cell lines. The double positive (CD24+ESA+) and double negative (CD24-ESA-) pancreatic cancer cells were isolated from PANC-1 and L3.6pl, and their self-renewal ability, tumorigenicity as well as sensitivity to gemcitabine were then evaluated. Results showed that there existed heterogeneity in expression levels of stemness-associated surface markers among pancreatic cancer cell lines. CD24+ESA+ pancreatic cancer cells exhibited increased tumorigenicity and decreased chemosensitivity to gemcitabine as compared to CD24-ESA- cells. Besides, the double positive (CD24+ESA+) subpopulation also exhibited greater expression level of Pim-3 when compared with the double negative (CD24-ESA-) ones. Furthermore, silencing of Pim-3 in pancreatic cancer cells leads to decreased proportions of both single positive (CD24+ and ESA+) and double positive (CD24+ESA+) pancreatic cancer cells. Overexpression of Pim-3 was associated with increased levels of some stemness-associated transcription factors (STAT3, etc.). Moreover, the phosphorylation level and transcriptional activity of STAT3 were decreased in Pim-3 silenced pancreatic cancer cells and restoration of its activity results in restitution of stem cell-like phenotypes. Therefore, Pim-3 maintains stemness of pancreatic cancer cells via activating STAT3 signaling pathway and might be used as a novel therapeutic target in pancreatic cancer.

High power, tunable mid-infrared BaGa4Se7 optical parametric oscillator pumped by a 2.1 µm Ho:YAG laser.

We, for the first time, demonstrate a tunable mid-infrared BaGa4Se7-based optical parametric oscillator pumped by a acousto-optical Q-switched Ho:YAG laser at 2090.6 nm. Up to 1.55 W of average power was generated in the 3-5 µm range, corresponding to an optical-to-optical conversion efficiency of 14.4% and a slope efficiency of 19.9%. The mid-IR radiation spectra were also seriously researched at different phase-matched angles. The tunable range was 3.49-4.13 µm for the signal, and 5.19-4.34 µm for the idler.

Pim-3 contributes to radioresistance through regulation of the cell cycle and DNA damage repair in pancreatic cancer cells.

Resistance of cancer cells to chemoradiotherapy is a major clinical problem in pancreatic cancer treatment. Therefore, understanding the molecular basis of cellular resistance and identifying novel targets are essential for improving treatment efficacy for pancreatic cancer patients. Previous studies have demonstrated a significant role for Pim-3 in pancreatic cancer survival against gemcitabine-induced genotoxic stress. Here, we observed that radiation treatment enhanced Pim-3 expression in human pancreatic cancer cells in vitro. Stable overexpression of Pim-3 in pancreatic cancer cells significantly protected cells against radiation treatment by attenuating G2/M phase cell cycle arrest and DNA damage response. Silencing of Pim-3 expression significantly elevated the phosphorylation of histone variant H2AX, a marker of DNA double strand breaks, and decreased the activation of ataxia-telangiectasia-mutated (ATM) kinase, along with its downstream targets, eventually enhancing the radiosensitivity of human pancreatic cancer cells in vitro and in vivo. Hence, we demonstrated a novel function for Pim-3 in human pancreatic cancer cell survival against radiation. Targeting Pim-3 may be a promising way to improve treatment efficacy in combination with radiotherapy in human pancreatic cancer.

FGF-1/-3/FGFR4 signaling in cancer-associated fibroblasts promotes tumor progression in colon cancer through Erk and MMP-7.

Cancer-associated fibroblasts (CAFs), as the activated fibroblasts in the tumor stroma, are important modifiers of tumour progression. In the present study, we observed that azoxymethane and dextran sodium sulfate treatments induced increasingly severe colorectal mucosal inflammation and the intratumoural accumulation of CAFs. Fibroblast growth factor (FGF)-1 and FGF-3 were detected in infiltrating cells, and FGFR4, the specific receptor for FGF-1 and FGF-3, was detected in colon cancer tissues. The phosphorylation of FGFR4 enhanced the production of metalloproteinase (MMP)-7 and mitogen-activated protein kinase kinase (Mek)/extracellular signal-regulated kinase (Erk), which was accompanied by excessive vessel generation and cell proliferation. Moreover, we separated CAFs, pericarcinoma fibroblasts (PFs), and normal fibroblasts (NFs) from human colon tissue specimens to characterize the function of CAFs. We observed that CAFs secrete more FGF-1/-3 than NFs and PFs and promote cancer cell growth and angiogenesis through the activation of FGFR4, which is followed by the activation of Mek/Erk and the modulation of MMP-7 expression. The administration of FGF-1/-3-neutralizing antibodies or the treatment of cells with FGFR4 siRNA or the FGFR4 inhibitor PD173074 markedly suppressed colon cancer cell proliferation and neovascularization. These observations suggest a crucial role for CAFs and FGF signaling in the initiation and progression of colorectal cancer. The inhibition of the FGF signaling pathway may be a useful strategy for the treatment of colon cancer.

miR-33a suppresses the nuclear translocation of ß-catenin to enhance gemcitabine sensitivity in human pancreatic cancer cells.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, partly due to its high level of drug resistance. ß-Catenin is critical for drug resistance in pancreatic cancer, which occurs through multiple mechanisms. Here, we observed that miR-33a targeted the 3'UTR of ß-catenin, inducing apoptosis and inhibiting the growth of human pancreatic cancer cells. Moreover, gemcitabine (GEM) treatment enhanced ß-catenin expression by reducing miR-33a expression in a dose-dependent manner. GEM-resistant MiaPaCa-2(res) cells with a low level of miR-33a expression and high level of ß-catenin expression adopted spindle-shaped morphologies, similar to their morphologies during the epithelial-to-mesenchymal transition (EMT), and their normal morphologies were restored by miR-33a overexpression. Furthermore, miR-33a downregulated ß-catenin nuclear translocation, decreasing the transcription of survivin, cyclin D1, and MDR-1, and the protein expression of slug, vimentin, and N-cadherin, thereby mediating sensitization to GEM. Thus, miR-33a might function as a tumor suppressor to downregulate ß-catenin expression, affecting cell growth, apoptosis, the EMT, and GEM resistance.

MicroRNA-33a-mediated downregulation of Pim-3 kinase expression renders human pancreatic cancer cells sensitivity to gemcitabine.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, with less than 5% of patients surviving 5 years beyond diagnosis. Systemic therapies, particularly gemcitabine, have a modest clinical benefit, but chemoresistance limits their efficacy. Here, we demonstrate that plasma miR-33a levels positively correlated with miR-33a levels in tumor tissues of patients with PDAC and are a good prognostic indicator of overall survival. Overexpression of miR-33a inhibited tumor cell proliferation and increased the chemosensitivity to gemcitabine both in vitro and in vivo. Moreover, miR-33a targets Pim-3 directly in PDAC. Pim-3 expression was a prognostic indicator related to poor survival in pancreatic cancer patients. Plasma miR-33a levels were significantly lower in pancreatic cancer patients with high Pim-3 protein expression than in healthy controls. Furthermore, overexpression of miR-33a in pancreatic cancer cell lines suppressed Pim-3 expression, leading to downregulation of the AKT/Gsk-3ß/ß-catenin pathway. Overall, these results indicate that miR-33a functions as a tumor suppressor that downregulates Pim-3 kinase expression to inhibit both pancreatic tumor growth and gemcitabine resistance via the AKT/ß-catenin pathway. Hence, detection of plasma miR-33a may be a simple and convenient method of predicting therapeutic responses.

Orthotopic inflammation-related pancreatic carcinogenesis in a wild-type mouse induced by combined application of caerulein and dimethylbenzanthracene.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human malignancies, with a poor long-term prognosis, and effective therapeutic options are lacking. Observing the dynamics of the pathogenesis of pancreatic intraepithelial neoplasia (PanIN) and PDAC in tumor models can facilitate understanding of the molecular mechanisms involved in early PDAC. Furthermore, it can compensate for the research limitations associated with analyzing clinical specimens of late-stage PDAC. In this study, we orthotopically treated the pancreas with dimethylbenzanthracene (DMBA) combined with caerulein in wild-type C57BL/6 J mice to induce inflammation-related pancreatic carcinogenesis. We observed that DMBA and caerulein treatment induced a chronic consumptive disease, which caused a decrease in the relative body and pancreas weights, diminishing the health status of the mice and enhancing the inflammation-related histological changes. Moreover, mid-dose and high-frequency treatment with caerulein caused prolonged inflammatory damage to the pancreas and contributed to a permissive environment for the development of PDAC. CXCL12/CXCR4, CCL2/CCR2, and several cytokines, such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α were upregulated in the tumor tissue of DMBA and caerulein-induced PDAC mice. This orthotopic mouse pancreatic carcinogenesis model mimic human disease because it reproduces a spectrum of pathological changes observed in human PDAC, ranging from inflammatory lesions to pancreatic intraepithelial neoplasia. Thus, this mouse model may improve the understanding of molecular mechanisms underlying the injury-inflammation-cancer pathway in the early stages of pancreatic carcinogenesis.

Gemcitabine-induced CXCL8 expression counteracts its actions by inducing tumor neovascularization.

Patients with pancreatic ductal adenocarcinoma (PDAC) are frequently complicated with metastatic disease or locally advanced tumors, and consequently need chemotherapy. Gemcitabine is commonly used for PDAC treatment, but with limited efficacy. The capacity of gemcitabine to generate reactive oxygen species (ROS) in human pancreatic cancer cells, prompted us to examine its effects on the expression of pro-inflammatory cytokines and chemokines. We observed that gemcitabine enhanced selectively the expression of CXCL8 in human pancreatic cancer cells through ROS generation and NF-κB activation. In vitro blocking of CXCL8 failed to modulate gemcitabine-mediated inhibition of cell proliferation in human pancreatic cancer cells. Gemcitabine also enhanced CXCL8 expression in pancreatic cancer cells in xenografted tumor tissues. Moreover, anti-CXCL8 antibody treatment in vivo attenuated tumor formation as well as intra-tumoral vascularity in nude mice, which were transplanted with Miapaca-2 cells and treated with gemcitabine. Thus, gemcitabine-induced CXCL8 may counteract the drug through inducing neovascularization.