Thioridazine reverses trastuzumab resistance in gastric cancer by inhibiting S-phase kinase associated protein 2-mediated aerobic glycolysis

BACKGROUND Trastuzumab constitutes the fundamental component of initial therapy for patients with advanced human epidermal growth factor receptor 2(HER-2)-positive gastric cancer(GC).However,the efficacy of this treatment is hindered by substantial challenges associated with both primary and acquired drug resistance.While S-phase kinase associated protein 2(Skp2)overexpression has been implicated in the malignant progression of GC,its role in regulating trastuzumab resistance in this context remains uncertain.Despite the numerous studies investigating Skp2 inhibitors among small molecule compounds and natural products,there has been a lack of successful commercialization of drugs specifically targeting Skp2.AIM To discover a Skp2 blocker among currently available medications and develop a therapeutic strategy for HER2-positive GC patients who have experienced progression following trastuzumab-based treatment.METHODS Skp2 exogenous overexpression plasmids and small interfering RNA vectors were utilized to investigate the correlation between Skp2 expression and trastuzumab resistance in GC cells.Q-PCR,western blot,and immunohistochemical analyses were conducted to evaluate the regulatory effect of thioridazine on Skp2 expression.A cell counting kit-8 assay,flow cytometry,a amplex red glucose/glucose oxidase assay kit,and a lactate assay kit were utilized to measure the proliferation,apoptosis,and glycolytic activity of GC cells in vitro.A xenograft model established with human GC in nude mice was used to assess thioridazine's effectiveness in vivo.RESULTS The expression of Skp2 exhibited a negative correlation with the sensitivity of HER2-positive GC cells to trastuzumab.Thioridazine demonstrated the ability to directly bind to Skp2,resulting in a reduction in Skp2 expression at both the transcriptional and translational levels.Moreover,thioridazine effectively inhibited cell proliferation,exhibited antiapoptotic properties,and decreased the glucose uptake rate and lactate production by suppressing Skp2/protein kinase B/mammalian target of rapamycin/glucose transporter type 1 signaling pathways.The combination of thioridazine with either trastuzumab or lapatinib exhibited a more pronounced anticancer effect in vivo,surpassing the efficacy of either monotherapy.CONCLUSION Thioridazine demonstrates promising outcomes in preclinical GC models and offers a novel therapeutic approach for addressing trastuzumab resistance,particularly when used in conjunction with lapatinib.This compound has potential benefits for patients with Skp2-proficient tumors.

Analysis of Subcellular Localization and Pathogenicity of Plum Bark Necrosis Stem-Pitting Associated Virus Protein P6

Infection of plum bark necrosis stem pitting associated virus(PBNSPaV)has been reported in many Prunus species in several countries,causing significant economic losses.The very small proteins encoded by plant viruses are often overlooked due to their short sequences and uncertain significance.However,numerous studies have indicated that they might play important roles in the pathogenesis of virus infection.The role of small hydrophobic protein P6,encoded by the open reading frame 2 of PBNSPaV,has not been well explored.In this study,we amplified the P6 fragment from a PBNSPaV isolate by RT-PCR using specific primers and found that it is 174 bp long and encodes a protein of approximately 6.3 kD with a transmembrane domain.Subcellular localization analysis of P6 proteins in tobacco leaves showed that P6 localizes to the cytomembrane and nuclear membrane.To further clarify the pathogenicity of P6 proteins,we constructed a PVX-P6 expression vector by inserting the p6 fragment into a potato virus X(PVX)-based vector and transformed it into Agrobacterium tumefaciens GV3101.Infiltration of Nicotiana benthamiana(N.benthamiana)with the PVX vector-transformed A.tumefaciens led to slight mosaic symptoms at 14 days of post-inoculation.Meanwhile,infiltration with the PVX-P6 vector-transformed A.tumefaciens resulted in no significant symptoms.These results demonstrated that heterologous expression of P6 in N.benthamiana could not enhance the pathogenicity of PVX.Our study indicates that P6 may not be a potential pathogenic factor associate with the causing of symptoms,and the mode of action of PBNSPaV-P6 protein remains to be further studied.

Corepressor metastasis-associated protein 3 modulates epithelial-to-mesenchymal transition and metastasis

Worldwide,metastasis is the leading cause of more than 90%of cancer-related deaths.Currently,no specific therapies effectively impede metastasis.Metastatic processes are controlled by complex regulatory networks and transcriptional hierarchy.Corepressor metastasis-associated protein 3(MTA3)has been confirmed as a novel component of nucleosome remodeling and histone deacetylation(NuRD).Increasing evidence supports the theory that,in the recruitment of transcription factors,coregulators function as master regulators rather than passive passengers.As a master regulator,MTA3 governs the target selection for Nu RD and functions as a transcriptional repressor.MTA3dysregulation is associated with tumor progression,invasion,and metastasis in various cancers.MTA3 is also a key regulator of E-cadherin expression and epithelial-to-mesenchymal transition.Elucidating the functions of MTA3 might help to find additional therapeutic approaches for targeting components of NuRD.

Comparisons of voided urine cytology, nuclear matrix protein-22 and bladder tumor associated antigen tests for bladder cancer of geriatric male patients in Taiwan, China

Aim： To compare the results of bladder tumor associated antigen （BTA TRAK）, nuclear matrix protein 22 （NMP 22） and voided urine cytology （VUC） in detecting bladder cancer. Methods： A total of 135 elderly male and 50 healthy volunteers enrolled in this study were classified into three groups： （i） 93 patients with bladder cancer; （ii） 42 patients with urinary benign conditions; and （iii） 50 healthy volunteers. BTA TRAK and NMP 22 kits were used to detect bladder cancer. Voided urine cytology was used to compare the sensitivity and specificity of the screening tests. Results： The sensitivity and specificity of cytology, BTA TRAK and NMP 22 were 24% and 97%, 51% and 73%, 78% and 73%, respectively. The level of NMP 22 increased with tumor grading. The BTA TRAK kit has the lowest sensitivity among the screening tests. The NMP 22 with the best sensitivity can be an adjunct to cytology for evaluating bladder cancer. Conclusion： The NMP 22 test has a better correlation with the grading of the bladder cancer than BTA TRAK. As cytology units are typically not available in hospitals or in outpatient clinics, NMP 22 might be a promising tool for screening bladder cancer.

Influence of chronic intermittent hypoxia on growth associated protein 43 expression in the hippocampus of young rats

This study aimed to explore the pathological change to hippocampal neurons and the expression of growth associated protein 43 in 21-day-old young rats following chronic intermittent hypoxia. Hematoxylin-eosin staining results showed varying degrees of degeneration and necrosis in hippocampal neurons depending on the modeling time. Immunohistochemistry revealed that growth associated protein 43 expression in young rats following chronic intermittent hypoxia decreased, but that levels were still higher than those of normal rats at each time point, especially 4 weeks after modeling. During 1 5 weeks after modeling, a slow growth in rat weight was observed. Experimental findings indicate that chronic intermittent hypoxia may induce growth dysfunction and necrosis of hippocampal neurons, as well as increase the expression of growth associated protein 43 in young rats.

Correlation between synaptic plasticity, associated proteins, and rehabilitation training in a rat model of cerebral infarction

All motions provide sensory, motoric, and reflexive input to the central nervous system, as well as playing an important role in cerebral functional plasticity and compensation. Cerebral plasticity has become the theoretical basis of neurorehabilitation. Studies of cerebrovascular disease, in particular, demonstrate that regeneration is accompanied by multiple forms of plasticity, such as functional and structural, in different phases of stroke rehabilitation. This study was designed to measure synaptic plasticity and expression of associated proteins to analyze the effect of rehabilitation training on learning and memory in a rat model of cerebral infarction. Results suggest that rehabilitation training increases expression of nerve growth factor associated protein 43, brain-derived neurotrophic factor, and neural cell adhesion molecules, and also promotes cerebral functional plasticity.

Adjuvant role of Pseudomonas flagellin for Acinetobacter baumannii biofilm associated protein

AIM To study immunogenicity of Pseudomonas N terminal flagellin as an adjuvant for Acinetobacter baumannii(A. baumanni) biofilm associated protein(Bap).METHODS The N terminal flagellin gene was amplified. The p ET28a(+) and polymerase chain reaction products weredigested with HindⅢ and Eco R Ⅰ. The ligation of N terminal flagellin into p ET28a(?+) was performed using T4 DNA ligase and was then transformed into Escherichia coli BL21(DE3) as a suitable expression host. p ET28a(?+) vector harboring a conserved region of Bap from our previous work was used. The recombinant proteins were expressed, analyzed by SDS-PAGE method and was purified by affinity chromatography with His-Tag residues followed by confirmation with western blotting. Mice were immunized with recombinant N terminal flagellin and Bap subunits. The immunized animals were intranasally(i.n) challenged with A. baumannii and Pseudomonas aeruginosa(P. aeruginosa).RESULTS The flagellin enhanced the immunogenicity of Bap causing an increase in specific Ig G titers in serum(P < 0.001). Internal organs, i.e., liver, lung and spleen of the BapFlagellin immunized group challenged with A. baumannii showed significantly lower bacterial load compared to the control group. The bacterial loads were studied in internal organs. A. baumannii infected immunized animals with Bap-Flagellin exhibited internal organs with minor bacterial load while P. aeruginosa PAO1 infected group showed heavy bacterial load of(4.3 ± 0.12) × 106,(1.1 ± 0.01) × 106 and(2.2 ± 0.22) × 106 per gram of lungs, liver and spleen respectively. Bacterial loads were detected per gram of lungs, liver and spleen of the mice group immunized with Bap were(1.2 ± 0.06) × 107,(11.1 ± 0.041) × 105 and(3.6 ± 0.42) × 106 respectively. In vivo neutralization assay indicated that all experimental mice groups, except for Flagellin administered group was significantly(P < 0.05) protected against A. baumannii. CONCLUSION These results demonstrate that P. aeruginosa Flagellin as an adjuvant for Bap A. baumannii could be a useful model to evaluate new vaccine against A. baumannii.

Association of Lysosome Associated Protein Transmembrane 4 Beta Gene Polymorphism with the Risk of Pancreatic Cancer

Objective： Lysosome associated protein transmembrane 4 beta （LAPTM4B） was originally identified as a gene in human hepatocellular carcinoma （HCC）. It was successfully cloned by fluorescence differential display, rapid amplification of cDNA ends （RACE） and reverse transcription polymerase chain reaction （RT-PCR）. Previous study showed that the novel gene played an important role in the occurrence, development, migration and prognosis of tumors. Pancreatic cancer is an aggressive malignancy with the majority of patients dying within one year after diagnosis. This study tries to find out the relationship between lysosome associated protein transmembrane 4 beta gene polymorphism and the susceptibility of pancreatic cancer. Methods： A case-control study was conducted in China, including 58 pancreatic cancer cases and 156 healthy controls. Human genomic DNA was used as the template, polymerase chain reaction （PCR） was used to detect the distribution of LAPTM4B genotype. Analyses Odds ratio （OR） and corresponding 95% confidence interval （95%CI） with logistic regression were performed. Results： Two alleles of LAPTM4B generated three kinds of genotypes in population, ＊1/1, ＊1/2, and ＊2/2. The genotype frequency of ＊1/1, ＊1/2 and ＊2/2 in the pancreatic cancer group were 41.4%, 44.8% and 13.8% respectively, which were not significantly different from those of healthy group （47.4%, 42.9%, 9.6%） （P=0.773, P=0.291）. Also the ＊2 allele frequency of LAPTM4B among pancreatic cancer had no significantly difference with the controls （P=0.354）. When compared to the ＊1 allele, the people with ＊2 allele had no increased risk of pancreatic cancer. Conclusion： The gene polymorphism of LAPTM4B may not influence the susceptibility of pancreatic cancer.

LncRNA-ATB promotes autophagy by activating Yes-associated protein and inducing autophagy-related protein 5 expression in hepatocellular carcinoma

BACKGROUND Long non-coding RNAs (lncRNAs) play important roles in many diseases, including hepatocellular carcinoma (HCC). Autophagy is a metabolic pathway that facilitates cancer cell survival in response to stress. The relationship between autophagy and the lncRNA-activated by transforming growth factor beta (lncRNA-ATB) in HCC remains unknown. AIM To explore the influence of lncRNA-ATB in regulating autophagy in HCC cells and the underlying mechanism. METHODS In the present study, we evaluated lncRNA-ATB expression in tumor and adjacent non-tumor tissues from 72 HCC cases by real-time PCR. We evaluated the role of lncRNA-ATB in the proliferation and clonogenicity of HCC cells in vitro. The effect of lncRNA-ATB on autophagy was determined using a LC3-GFP reporter and transmission electron microscopy. Furthermore, the mechanism by which lncRNA-ATB regulates autophagy was explored by immunofluorescence staining, RNA immunoprecipitation (RIP), and Western blot. RESULTS The expression of lncRNA-ATB was higher in HCC tissues than in normal liver tissues, and lncRNA-ATB expression was positively correlated with tumor size, TNM stage, and poorer survival of patients with HCC. Moreover, ectopic overexpression of lncRNA-ATB promoted cell proliferation and clonogenicnity of HCC cells in vitro. LncRNA-ATB promoted autophagy by activating Yesassociated protein (YAP). Moreover, lncRNA-ATB interacted with autophagy-related protein 5 (ATG5) mRNA and increased ATG5 expression. CONCLUSION LncRNA-ATB regulates autophagy by activating YAP and increasing ATG5 expression. Our data demonstrate a novel function for lncRNA-ATB in autophagy and suggest that lncRNA-ATB plays an important role in HCC.

Dexamethasone mediates protection against acute pancreatitis via upregulation of pancreatitis-associated proteins

AIM: To examine the influence of dexamethasone on pancreatitis-associated protein (PAP) gene expression using both in vitro and in vivo models of acute pancreati- tis and to study how PAP gene expression correlates with severity of pancreatitis. METHODS: In vitro, IL-6 stimulated pancreas acinar AR42J cells were cultured with increasing concentrations of dexamethasone and assayed for PAP expression (RT-PCR). In vivo , pancreatitis was induced in rats by retrograde injection of 40 g/L taurocholate into the pancreatic duct. Animals were pretreated with dexamethasone (2 mg/kg) daily or saline for 4 d. Pancreata and serum were harvested after 24 h and gene expression levels of PAPⅠ, Ⅱ and Ⅲ were measured by RT-PCR. Severity of pancreatitis was based on serum amylase, pancreatic wet weight, and histopathological score. RESULTS: In vitro, dexamethasone and IL-6 induced a marked transcription of PAPⅠ, Ⅱ and Ⅲ genes in AR42J cells at 24 h (P < 0.05 for all comparisons). In vivo, pancreas mRNA levels of PAPⅠ, Ⅱ or Ⅲ increased by 2.6-fold, 1.9-fold, and 1.3-fold respectively after dexa- methasone treatment, compared with saline treated ani- mals. Serum amylase levels and edema were significantly lower in the dexamethasone group compared with the saline group. Histopathologic evaluation revealed less inflammation and necrosis in pancreata obtained from dexamethasone treated animals (P < 0.05). CONCLUSION: Dexamethasone significantly decreases the severity of pancreatitis. The protective mechanism ofdexamethasone may be via upregulating PAP gene ex- pression during injury.

Metastasis-associated protein 1 induces VEGF-C and facilitates lymphangiogenesis in colorectal cancer

AIM:To study the correlation between high metastasisassociated protein 1(MTA1)expression and lymphangiogenesis in colorectal cancer(CRC)and its role in production of vascular endothelial growth factor-C(VEGF-C). METHODS:Impact of high MTA1 and VEGF-C expression levels on disease progression and lymphovasculardensity(LVD,D2-40-immunolabeled)in 81 cases of human CRC was evaluated by immunohistochemistry. VEGF-C mRNA and protein expressions in human LoVo and HCT116 cell lines were detected by real-time polymerase chain reaction and Western blotting,respectively,with a stable expression vector or siRNA. RESULTS:The elevated MTA1 and VEGF-C expression levels were correlated with lymph node metastasis and Dukes stages(P<0.05).Additionally,high MTA1 expression level was correlated with a large tumor size(P< 0.05).A significant correlation was found between MTA1 and VEGF-C protein expressions in tumor cells(r=0.371, P<0.05).Similar to the VEGF-C expression level,high MTA1 expression level was correlated with high LVD in CRC(P<0.05).Furthermore,over-expression of MTA1 significantly enhanced the VEGF-C mRNA and protein expression levels,whereas siRNAs-knocked down MTA1 decreased the VEGF-C expression level. CONCLUSION:MTA1,as a regulator of tumor-associated lymphangiogenesis,promotes lymphangiogenesis in CRC by mediating the VEGF-C expression.

Significance and relationship between Yes-associated protein and survivin expression in gastric carcinoma and precancerous lesions

AIM:To analyze the differences and relevance of Yes-associated protein (YAP) and survivin, and to explore the correlation and signifi cance of their expression in gastric carcinoma and precancerous lesions.METHODS: The PV9000 immunohistochemical method was used to detect the expression of YAP and survivin in 98 cases of normal gastric mucosa, 58 intestinal metaplasia (IM), 32 dysplasia and 98 gastric carcinoma.RESULTS: The positive rates of YAP in dysplasia (37.5%) and gastric carcinoma (48.0%) were significantly higher than that in normal gastric mucosa (13.3%), P<0.01. The positive rates of survivin in IM (53.4%), dysplasia (59.4%) and gastric carcinoma (65.3%) were significantly higher than in normal gastric mucosa (11.2%), P<0.01. Survivin expression gradually increased from 41.7% in well differentiated adenocarcinoma through 58.3% in moderately differentiated adenocarcinoma to 75.6% in poorly differentiated adenocarcinoma, with significant Rank correlation, rk=0.279, P<0.01. The positive rate of survivin in gastric carcinoma of diffused type (74.6%) was significantly higher than that in intestinal type (51.3%), P<0.05. In gastric carcinoma with lymph node metastasis (76.9%), the positive rate of survivin was signifi cantly higher than that in the group without lymph node metastasis (41.2%), P<0.01. In 98 cases of gastric carcinoma, the expression of YAP and of survivin were positively correlated, rk=0.246, P<0.01.CONCLUSION: YAP may play an important role as a carcinogenic factor and may induce survivin expression. Detecting both markers together may help in early diagnosis of gastric carcinoma.

Interactions between mycoplasma lipid-associated membrane proteins and the host cells

Mycoplamas are a group of wall-less prokaryotes widely distributed in nature, some of which are pathogenic for humans and animals. There are many lipoproteins anchored on the outer face of the plasma membrane, called lipid-associated membrane proteins (LAMPs). LAMPs are highly antigenic and could undergo phase and size variation, and are recognized by the innate immune system through Toll-like receptors (TLR) 2 and 6. LAMPs can modulate the immune system, and could induce immune cells apoptosis or death. In addition, they may associate with malignant transformation of host cells and are also con-sidered to be cofactors in the progression of AIDS.

Acute pancreatitis in aging animals:Loss of pancreatitis-associated protein protection?

AIM:To investigate the effect of age on severity of acute pancreatitis(AP) using biochemical markers,histology and expression of the protective pancreatitisassociated proteins(PAPs).METHODS:AP was induced via intraductal injection of 4% sodium taurocholate in young and old rats.Sera and pancreata were assayed at 24 h for the parameters listed above;we also employed a novel molecular technique to assess bacterial infiltration using polymerase chain reaction to measure bacterial genomic ribosomal RNA.RESULTS:At 24 h after induction of AP,the pancreata of older animals had less edema(mean ± SE histologic score of young vs old:3.11 ± 0.16 vs 2.50 ±-0.11,P < 0.05),decreased local inflammatory response(histologic score of stromal infiltrate:3.11 ± 0.27 vs 2.00 ± 0.17,P < 0.05) and increased bacterial infiltration(174% ± 52% increase from sham vs 377% ± 4%,P < 0.05).A decreased expression of PAP1 and PAP2 was demonstrated by Western blotting analysis and immunohistochemical staining.There were no differences in serum amylase and lipase activity,or tissue myeloperoxidase or monocyte chemotactic protein-1 levels.However,in the most-aged group,serum C-reactive protein levels were higher(young vs old:0.249 ± 0.04 mg/dL vs 2.45 ± 0.68 mg/dL,P < 0.05).CONCLUSION:In older animals,there is depressed PAP expression related to a blunted inflammatory response in AP which is associated with worsened bacterial infiltration and higher C-reactive protein level;this may explain the more aggressive clinical course.

Pancreatitis-associated protein:From a lectin to an anti-inflammatory cytokine

Pancreatitis-associated protein (PAP) was discovered in the pancreatic juice of rats with acute pancreatitis. PAP is a 16 kDa secretory protein structurally related to the C-type lectins although classical lectin-related function has not been reported yet. Then, it was demonstrated that PAP expression may be activated in some tissues in a constitutive or injury- and inflammation-induced manner. More recently, it has been found that PAP acts as an anti-inflammatory factor in vitro and in vivo. PAP expression can be induced by several pro- and anti-inflammatory cytokines and by itself through a JAK/STAT3-dependent pathway. PAP is able to activate the expression of the anti-inflammatory factor SOCS3 through the JAK/STAT3-dependent pathway. The JAK/STAT3/SOCS3 pathway seems to be a common point between PAP and several cytokines. Therefore, it is reasonable to propose that PAP is a new anti- inflammatory cytokine.

Molecular Cloning, and Characterization of an Adenylyl Cyclase-Associated Protein from Gossypium arboreum L.

The aim of this study was to clone CAP （adenylyl cyclase-associated protein） gene from Gossypium arboreum L. and develop a platform for expressing and purifying CAP protein, which is a base for the construction and function researches of CAP. In this work, a CAP homolog from cotton （DPL971） ovule was identified and cloned. And the cDNA sequence consisted of an open reading frame of 1 416 nucleotides encoding a protein of 471 amino acid residues with a calculated molecular weight of 50.6 kDa. To gain insight on the CAP role in cotton fiber development, the cloned CAP cDNA was expressed. A significant higher yield pure protein was obtained with the chromatographic method. Further experiments showed that the purified protein can bind with the actin in vitro indicating that the recombinant cotton CAP is functional. The procedure described here produced high yield pure protein through one chromatographic step, suitable for further structure-function studies.

Activation of Growth-associated Protein by Intragastric Brazilein in Motor Neuron of Spinal Cord Connected with Injured Sciatic Nerve in Mice

The purpose of this study is to explore the expression of growth-associated protein（GAP-43） in spinal cord segments connected with injured sciatic nerve by the treatment with brazilein in mice. Unilateral sciatic nerve interruption and anastomosis were performed. Physiological saline（blank group）, high dose, middle dose and low dose of brazilein were administrated intragastrically to healthy adult BALB/c mice in separate groups. L4―6 spinal segments connected with the sciatic nerve were harvested. Real-time PCR（Polymerase chain reaction） and Western blot analysis were performed to detect the expression of GAP-43 in spinal segments. Histological staining on myelin and the electrophysiology were performed to examine the sciatic nerve recovery. GAP-43 was activated in spinal cord L4―6 connected with injured sciatic nerve. In the survival time of 12 h, 24 h, 3 d, 5 d, 7 d and 14 d, GAP-43 expression in the motor neurons of spinal cord of the high dose group and that in the middle dose group were significantly higher than those on the low dose and blank groups. Myelin in the high dose group and that in the middle dose group were more mature and the potential amplitude and MNCV（motor nerve conduction velocity） in the high and middle dose groups were obviously higher than those in the low dose group and blank group. Brazilein facilitates the expression of GAP-43 in neurons in spinal cord L4―6 segments connected with injured sciatic nerve, which promotes nerve regeneration.

Amyloid precursor protein and growth-associated protein 43 expression in brain white matter and spinal cord tissues in a rat model of experimental autoimmune encephalomyelitis

Studies have demonstrated that amyloid precursor protein （APP） expression increases in multiple sclerosis tissues during acutely and chronically active stages. To determine the relationship between axonal injury and regeneration in multiple sclerosis, an animal model of experimental autoimmune encephalomyelitis was induced using different doses of myelin basic protein peptide. APP and growth-associated protein 43 （GAP-43）, which is considered a specific marker of neural regeneration, were assessed by western blot analysis. Expression of APP and GAP-43, as well as the correlation between these two proteins, in brain white matter and spinal cord tissues of experimental autoimmune encephalomyelitis rats at different pathological stages was analyzed. Results showed that APP and GAP-43 expression increased during the acute stage and decreased during remission, with a positive correlation between APP and GAP-43 expression in brain white matter and spinal cord tissues. These results suggest that APP and GAP-43 could provide nutritional and protective effects on damaged neurons.

Immunolocalization assessment of metastasis-associated protein I in human and mouse mature testes and its association with spermatogenesis

Aim： To investigate the stage-specific localization of metastasis-associated protein 1 （MTA1） during spermatogenesis in adult human and mouse testis. Methods： The immunolocalization of MTA1 was studied by immunohistochemistry and Western blot analysis. The distribution pattern of MTA1 in mouse testis was confirmed by using quantitative analysis of purified spermatogenic cells. Results： The specificity of polyclonal antibody was confirmed by Western blot analysis. MTA1 was found expressed in the nucleus of germ cells, except elongate spermatids, and in the cytoplasm of Sertoli cells; Leydig cells did not show any specific reactivity. MTA1 possessed different distribution patterns in the two species： in humans, the most intensive staining was found in the nucleus of round spermatids and of primary spermatocytes while in mice, the most intense MTA 1 staining was in the nucleus of leptotene, zygotene and pachytene spermatocytes. In both species the staining exhibited a cyclic pattern. Conclusion： The present communication initially provides new evidence for the potential role of MTA1 in mature testis. In addition, its distinctive expression in germ cells suggests a regulatory role of the peptide during spermatogenesis.

Analysis of the autophagy gene expression profile of pancreatic cancer based on autophagy-related protein microtubule-associated protein 1A/1B-light chain 3

BACKGROUND Pancreatic cancer is a highly invasive malignant tumor. Expression levels of the autophagy-related protein microtubule-associated protein 1 A/1 B-light chain 3(LC3) and perineural invasion(PNI) are closely related to its occurrence and development. Our previous results showed that the high expression of LC3 was positively correlated with PNI in the patients with pancreatic cancer. In this study, we further searched for differential genes involved in autophagy of pancreatic cancer by gene expression profiling and analyzed their biological functions in pancreatic cancer, which provides a theoretical basis for elucidating the pathophysiological mechanism of autophagy in pancreatic cancer and PNI.AIM To identify differentially expressed genes involved in pancreatic cancer autophagy and explore the pathogenesis at the molecular level.METHODS Two sets of gene expression profiles of pancreatic cancer/normal tissue(GSE16515 and GSE15471) were collected from the Gene Expression Omnibus.Significance analysis of microarrays algorithm was used to screen differentially expressed genes related to pancreatic cancer. Gene Ontology(GO) analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis were used to analyze the functional enrichment of the differentially expressed genes. Protein interaction data containing only differentially expressed genes was downloaded from String database and screened. Module mining was carried out by Cytoscape software and ClusterOne plug-in. The interaction relationship between the modules was analyzed and the pivot nodes between the functional modules were determined according to the information of the functional modules and the data of reliable protein interaction network.RESULTS Based on the above two data sets of pancreatic tissue total gene expression, 6098 and 12928 differentially expressed genes were obtained by analysis of genes with higher phenotypic correlation. After extracting the intersection of the two differential gene sets, 4870 genes were determined. GO analysis showed that 14 significant functional items including negative regulation of protein ubiquitination were closely related to autophagy. A total of 986 differentially expressed genes were enriched in these functional items. After eliminating the autophagy related genes of human cancer cells which had been defined, 347 differentially expressed genes were obtained. KEGG pathway analysis showed that the pathways hsa04144 and hsa04020 were related to autophagy. In addition,65 clustering modules were screened after the protein interaction network was constructed based on String database, and module 32 contains the LC3 gene,which interacts with multiple autophagy-related genes. Moreover, ubiquitin C acts as a pivot node in functional modules to connect multiple modules related to pancreatic cancer and autophagy.CONCLUSION Three hundred and forty-seven genes associated with autophagy in human pancreatic cancer were concentrated, and a key gene ubiquitin C which is closely related to the occurrence of PNI was determined, suggesting that LC3 may influence the PNI and prognosis of pancreatic cancer through ubiquitin C.