Pathological Changes in APP/PS-1 Transgenic Mouse Models of Alzheimer's Disease Treated with Ganoderma Lucidum Preparation.

Objective To explore the efficacy of ganoderma lucidum preparation(Ling Zhi) in treating APP/PS-1 transgenic mouse models of Alzheimer's disease(AD).Methods APP/PS-1 transgenic mice of 4 months were randomly divided into model group,ganoderma lucidum treatment groups,including high [2250 mg/(kg·d)] and middle [750 mg/(kg·d)] dose groups,i.e.LZ-H and LZ-M groups,and the positive control group(treated with donepezil hydrochloride [2 mg/(kg·d)]).In addition,C57BL/6J wild mice were selected as normal group.The animals were administered for 4 months.Histopathological examinations including hematoxylin-eosin(HE) staining,immunohistochemistry,special staining,and electron microscopy were applied,and then the pathological morphology and structures in different groups were compared. Results The senile plaques and neurofibrillar tangles in the cerebrum and cerebellum were dissolved or disappeared in LZ-H and LZ-M groups.Decrease of amyloid angiopathy was found in LZ-H and LZ-M groups.The immature neurons appeared more in hippocampus and dentate nucleus of LZ-H and LZ-M groups than those in AD model and donepezil hydrochloride groups(hippcampus:F=1.738,P=0.016;dentate nucleus:F=1.924,P=0.026),and these immature neurons differentiated to be neurons.More Purkinje cells loss occurred in AD model mice than that in LZ-H and LZ-M groups(F=9.46,P=0.007;F=9.46,P=0.010).The LZ-H and LZ-M groups had more new neuron stem cells grown up in cerebellum.Electromicroscopic examination showed the hippocampal neurons in LZ-H and LZ-M group were integrated,the nuclear membrane was intact,and the mitochondria in the cytoplasm,endoplasmic reticulum,Golgi bodies,microtubules,and synapses were also complete.The microglial cell showed no abnormality.No toxicity appeared in the pathological specimens of mice treated with ganoderma lucidum preparation.Conclusion The ganoderma lucidum preparation can dissolve and decline or dismiss the senile plaques and neurofibrillar tangles in the brain of AD mice and also reduce the amyloid angiopathy.

Increase of TNFα-stimulated osteoarthritic chondrocytes apoptosis and decrease of matrix metalloproteinases 9 by NF-κB inhibition.

OBJECTIVE: To investigate the in vitro effect of caffeic acid phenethyl ester (CAPE), a NF-κB inhibitor, on the apoptosis of osteoarthritic (OA) chondrocytes and on the regulation of the gelatinases matrix metalloproteinase 2 (MMP-2) and matrix metalloproteinase 9 (MMP-9). METHODS: Annexin V-FITC/propidium iodide (PI) labeling and western blotting were used to observe and determine the apoptosis in TNFα-stimulated primary cultured osteoarthritic chondrocytes. Also, gelatin zymography was applied to examine MMP-2 and MMP-9 activities in supernatants. RESULTS: It was confirmed by both flow cytometry and western blotting that chondrocytes from OA patients have an apoptotic background. Use of CAPE in combination with 10 ng/mL of TNFα for 24 h facilitated the apoptosis. MMP-9 in the supernatant could be autoactivated (from proMMP-9 to active MMP-9), and the physiologic calcium concentration (2.5 mmol/L) could delay the autoactivation of MMP-9. The activities of MMP-2 and MMP-9 in the fresh supernatant increased significantly in response to stimulation by 10 ng/mL of TNFα for 24 h. The stimulatory effect of TNFα just on proMMP-9 was counteracted significantly by CAPE. CONCLUSION: NF-κB could prevent chondrocytes apoptosis though its activation was attributed to the increase of proMMP-9 activity induced by TNFα (a pro-apoptotic factor). Therefore, therapeutic NF-κB inhibitor was a 'double-edged swords' to the apoptosis of chondrocytes and the secretion of MMP-9.

Low cholesteryl ester transfer protein and phospholipid transfer protein activities are the factors making tree shrew and beijing duck resistant to atherosclerosis.

BACKGROUND: Tree shrew and beijing duck are regarded as animal models resistant to atherosclerosis (AS). This study was carried out to discover the potential mechanism. METHODS: Blood samples were collected from healthy men and male animals. Plasma lipid profile and activities of cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) were measured, compared and analyzed in human, tree shrew, and Beijing duck. RESULTS: The results showed that there were species differences on plasma lipid profile and activities of CETP and PLTP in the three species. Compared with human, tree shrew and beijing duck had higher high density lipoprotein cholesterol (HDL-C)/total cholesterol (TC) and HDL-C/low density lipoprotein cholesterol (LDL-C) ratios, but lower CETP and PLTP activities. In the three species, CETP and PLTP activities were negatively related with the ratio of HDL-C/LDL-C. CONCLUSIONS: The present study suggested that low plasma CETP and PLTP activities may lead to a high HDL-C/LDL-C ratio and a high resistance to AS finally in tree shrew and beijing duck. Moreover, low PLTP activity may also make the animals resistant to AS by the relative high vitamin E content of apoB-containing lipoproteins and high anti-inflammatory and antioxidative properties of HDL particles. A detailed study in the future is recommended.

[Anti-inflammatory action of lipid-bound apoA-I cysteine mutants].

OBJECTIVE: To determine the anti-inflammatory functions of different cysteine mutants of apolipoprotein A-I recombinant HDLs. METHODS: The recombinant HDLs (named rHDL52, rHDL107, rHDL173, rHDLwt) were reconstituted by mixing wild types or their mutants with dipalmitoyl phosphatidylcholine. And the in vivo effects on lipopolysaccharide (LPS)-induced endotoxemia were examined in mice. The plasma levels of plasma tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 in by ELISA were tested. And we also set up two control groups: LPS and saline. RESULTS: The rHDL52 mice had a significant decrease of plasma TNF-alpha and IL-1beta and the protection of lung against acute injury. 24 h post-injection as compared with rHDLwt group [TNF-alpha: (135.28 +/- 12.84) pg/ml, IL-1beta: (82.00 +/- 8.19) pg/ml], the rHDL52 mice exhibited a higher capability of lowering the plasma levels of TNF-alpha and IL-1beta [(39.66 +/- 2.44) pg/ml, (66.83 +/- 6.24) pg/ml, both P < 0.05]. And, as indicated by histological sections of lung tissue, the rHDL52 mice could also lower the infiltration of inflammatory cells in lung. CONCLUSION: rHDL52 has a higher anti-inflammation capability than wild type rHDLwt.

[Effect of lipid-bound apoA-I cysteine mutants upon lipopolysaccharide-induced endotoxemia in mice].

OBJECTIVE: To determine the anti-inflammatory functions of different cysteine mutants of apolipoprotein A-I recombinant HDLs. METHODS: The authors reconstituted recombinant HDLs (namely rHDL74, rHDL129, rHDL195 and rHDL228) by mixing wild type or those mutants with dipalmitoyl phosphatidylcholine and examined their in vivo effects upon LPS-induced endotoxemia in mice. RESULTS: At 24 h post-injection, mice receiving rHDL74 [TNF-alpha: (24 +/- 3) pg/ml; IL-1beta: (45 +/- 5) pg/ml] had a significant decrease of plasma tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) as compared with control mice receiving either saline or rHDLwt [TNF-alpha: (135 +/- 12) pg/ml; IL-1beta: (82 +/- 8) pg/ml, P < 0.05]. Administration of rHDL74 to mice injected with LPS also led to a protection of lung against acute injury and attenuation of endotoxin-induced clinical symptoms in mice as compared with controls injected with LPS only. CONCLUSION: Compared with rHDLwt, rHDL74 exhibits higher anti-inflammation capabilities. And it may be a potential clinical candidate for therapy for endotoxin-induced septic shock.

Exogenous expression of Esophagin/SPRR3 attenuates the tumorigenicity of esophageal squamous cell carcinoma cells via promoting apoptosis.

Esophagin/SPRR3 is one of the cornified-envelope structural precursor proteins, which is expressed during epithelia cell differentiation. In 1996, another research group discovered, and our own laboratory subsequently confirmed, frequent and dramatic decreased Esophagin/SPRR3 expression in esophageal squamous cell carcinoma (ESCC). However, the role of Esophagin/SPRR3 in tumorigenesis of esophageal epithelium remains undetermined. In this study, we demonstrate that expression of Esophagin/SPRR3 is frequently downregulated in ESCC. In contrast, no correlations between downregulation of Esophagin/SPRR3 expression and clinicopathologic characteristics were observed. Diminished Esophagin/SPRR3 expression was present in dysplastic epithelia, suggesting that Esophagin/SPRR3 alteration could represent an early event in squamous carcinogenesis of the esophagus. Exogenous expression of Esophagin/SPRR3 significantly suppressed the ability of ESCC cells to form colonies in plastic and soft agar, as well as tumor formation in vivo. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end label assay and immunofluorescence analysis of the active form of Caspase 3 indicated that dysregulated apoptosis might contribute to reduced tumorigenicity. In particular, upregulation of CDK11p46 protein was observed in ESCC cells expressing Esophagin/SPRR3, but not in control cells, indicating that Esophagin/SPRR3-induced apoptosis may be due, at least in part, to increased expression of CDK11p46 protein. These findings suggest that Esophagin/SPRR3 may play a role in the maintenance of normal esophageal epithelial homeostasis, and that aberrant expression of Esophagin/SPRR3 may contribute to the tumorigenesis of ESCC.

Comparative proteomic analysis of rat juvenile and adult dura.

BACKGROUND: It has been widely observed that infants and young children can reossify large calvarial defects when they are younger than 2 years of age; afterwards, they lose this regenerative potential. Previous studies have implicated that the dura mater serves as a key regulator of calvarial regeneration. However, the molecular mechanism of calvarial reossification remains elusive. METHODS: In order to identify the proteins that may participate in this process, we performed a proteome-wide comparison of the protein expression levels of immature and mature dura using 2D electrophoresis and MALDI-TOF mass spectrometry. The Western blotting was used to verify the results of the 2D electrophoresis/MALDI-TOF mass spectrometry. RESULTS: Eleven proteins were found to express with significant differences in the immature and the mature dura. Among them, the emergence of vimentin, tropomyosin, beta-actin and gamma-actin were further confirmed by the Western blotting analysis. CONCLUSION: The proteins and proteomic profiles provide a better understanding of the molecular mechanism of calvarial regeneration.

Functional analysis of low-density lipoprotein receptor in homozygous familial hypercholesterolemia patients with novel 1439 C-->T mutation of low-density lipoprotein receptor gene.

BACKGROUND: Familial hypercholesterolemia (FH), caused by low density lipoprotein (LDL) receptor (LDL-R) gene mutations, is associated with increased risk of premature coronary heart disease. Until now, limited molecular data concerning FH are available in China. The present study described the clinical profiles and cell biological defects of a Chinese FH kindred with novel LDL-R gene mutation. METHODS: The patient's LDL-R gene coding region was sequenced. The patient's lymphocytes were isolated and the LDL-R expression, binding and up-take functions were observed by immunohistochemistry staining and flow cytometry detection. The patient's heart and the major large vessels were detected by vessel ultrasound examination and myocardial perfusion imaging (MPI). RESULTS: The patient's LDL-R expression, LDL binding and up-take functions were significantly lower than normal control (39%, 63% and 76% respectively). A novel homozygous 1439 C-->T mutation of the LDL-R gene was detected in the patient and his family. ECG showed atypical angina pectoris. Echocardiogram showed stenosis of the coronary artery and calcification of the aortic valve and its root. Blood vessel ultrasound examination showed the thickness of large vessel intima, and the vessel lumen was narrowed by 71%. MPI showed ischemic changes. CONCLUSIONS: The LDL-R synthesis dysfunction of FH patients leads to arterial stenosis and calcification, which are the major phenotype of the clinical disorder. The mutation of the LDL-R gene is determined. These data increase the mutational spectrum of FH in China.

[Relationship between plasma protein expression profiles and states of Zang-Fu organs in patients with phlegm or blood stagnation syndromes due to hyperlipidemia and atherosclerosis].

OBJECTIVE: To investigate the relationship between the plasma biomarker proteins and the states of Zang-Fu organs in patients with phlegm or blood stagnation syndromes due to hyperlipidemia and atherosclerosis. METHODS: The states of Zang-Fu organs in 146 patients with hyperlipidemia and atherosclerosis were diagnosed by syndrome differentiation of traditional Chinese medicine. The plasma proteins from these patients were separated by two-dimensional polyacrylamide gel electrophoresis (2-DE). Differential protein profiling was established by Image Master 6.0 software, and the differential proteins were analyzed by quadrupole time of flight mass spectrometry (Q-TOF-MS). The association between the plasma biomarker proteins and the states of Zang-Fu organs was analyzed by graphical models. RESULTS: The biomarker proteins such as fibrinogen gamma chain, albumin and apolipoprotein AI (precursor) in discrimination of the patients with phlegm syndrome from phlegm accumulating with stagnation syndrome were correlated with the deficiency of kidney-qi, heart-qi and spleen-qi. Among the four biomarker proteins in discrimination of the patients with phlegm syndrome from blood stagnation syndrome, albumin, adrenomedullin binding protein (precursor) and haptoglobin (precursor) were correlated with the deficiency of kidney-qi and heart-qi, but complement component C4 was independent of the deficient Zang-Fu organs. The biomarker albumin was associated with the deficiency of kidney-qi, heart-qi and spleen-qi, and adrenomedullin binding protein (precursor) was correlated with the deficiency of spleen-qi in discrimination of the patients with blood stagnation syndrome from phlegm accumulating with stagnation syndrome. As the potential biomarker proteins in discrimination of the patients with non-phlegm and non-stagnation syndrome from phlegm accumulating with stagnation syndrome, the fibrinogen beta chain was related with the deficiency of kidney-qi, and apolipoprotein AI (precursor) was correlated with both the deficiency of kidney-qi and heart-qi. CONCLUSION: There exists inherent correlation between the states of Zang-Fu organs and the plasma probable biomarker proteins in the patients with different phlegm or blood stagnation syndromes due to hyperlipidemia and atherosclerosis.

[Structure and function of apolipoprotein and prevention and therapy of virus diseases].

Apolipoprotein, an important component of the lipoproteins, modulates the activity of enzyme, introduces the binding of cell receptor and lipoproteins, and keeps the structural stability of lipoproteins. The amphipathic helices structure in apolipoproteins is the structural basis that it binds and transports lipids. A certain envelope glycoprotein (gp) in the outer membrane of HIV also has been found to be with such amphipathic helices structure. Recent studies have shown that the liposome consisted of apolipoproteins and phospholipids may defend against HCV, HIV, and herpes simplex virus, and even neutralize the endotoxin released by bacteria. The liposome made up of apolipoproteins and phospholipid has became a potential carrier for anti-tumor and anti-virus drugs.

[Structure analysis of apolipoprotein B 3' variable number of tandem repeats].

OBJECTIVE: To study the distribution, frequency and structure of variable number of tandem repeats (VNTR) in 3' region of apoB gene in Chinese population. METHODS: Genomic DNA was extracted from peripheral blood obtained under consent from randomly-chosen 522 individuals who came to the hospital for physical examination, and used to screen for polymorphisms of 3' VNTR of the apoB gene by employing polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), gradient polyacrylamide gel electrophoresis, cloning and sequencing. RESULTS: Sixteen types of alleles of apoB 3oVNTR were identified, among which heterozygotes were more than homozygotes. The biggest allele is HVE58, and the smallest one is HVE22. HVE34 had the highest frequency (40.4%), followed by HVE32 (34.7%). This showed significant difference from the allelic distribution of other populations (Caucasian and Swedish). Through sequencing of 60 alleles, a new isomer (Y-A=ATAATTAAATATTT) and four new types of alleles were found. CONCLUSION: The Chinese population we studied had a higher frequency of small alleles and showed a difference in allelic structure and frequency distribution from European and American in this populations.

Three isoforms of annexin I are preferentially expressed in normal esophageal epithelia but down-regulated in esophageal squamous cell carcinomas.

The development and progression of human cancer are believed to be due to the alterations of multiple genes or/and their protein products. For identifying the proteins associated with esophageal cancer, we analysed the protein profiles of 24 pairs of esophageal squamous cell carcinomas/matched adjacent normal epithelia. Microdissection of routinely unstained frozen sections was performed to purify cancerous and epithelial cells. The protein expression profiles were obtained by two-dimensional electrophoresis. Selected proteins dysregulated in tumors were identified by MALDI-TOF-MS. Three isoforms of annexin I were detected in normal esophageal mucosa and down-regulated in esophageal squamous cell carcinomas. RT-PCR analysis showed annexin I mRNA levels were significantly reduced in 17 out of 24 carcinomas. Immunohistochemistry demonstrated that annexin I appeared strong positive in all normal epithelia layers except basal cells. In cancer tissues, decreased expression of annexin I was observed in 12 out of 16 well differentiated tumors, 16 out of 17 moderately differentiated tumors, and 3 out of 3 poorly differentiated tumors as compared with the corresponding normal esophageal epithelia. There was a significant correlation between annexin I expression and the status of tumor differentiation. Well differentiated tumors presented stronger immunohistochemical reaction than moderately and poorly differentiated tumors. These data suggested that there existed three different isoforms of annexin I in normal esophageal epithelia, which may be the results of post-translational modification. Down-expression of three annexin I isoforms was a frequent event in esophageal carcinogenesis.

[Molecular basis of familial hypercholesterolemia-like phenotype heterogeneity].

Familial hypercholesterolemia (FH),which is caused by low-density lipoprotein (LDL) receptor mutation, leads to LDL-R dysfunction and high plasma LDL level and early onset of cardiovascular disease. LDL-R mutation has been regarded as the only cause of FH phenotype. However, evidences from recent studies showed that another six gene mutations can also result in FH like phenotype through different mechanism. Further studies on these genes will clarify the mechanism of plasma LDL regulation and provide the molecular basis for the diagnosis and treatment of patients with FH-like phenotype. This review summarizes recent studies on the molecular basis of FH-like phenotype heterogeneity in the hope of drawing more attention to the disease.

Role of histamine in airway remodeling of asthmatic guinea pig.

To investigate the role of histamine in airway remodeling, 50 healthy guinea pigs were divided into 5 groups: control group: nebulized inhalation of distilled water for 8 weeks; asthma model group: nebulized inhalation of ovalbumin (OVA) for 8 weeks after sensitization; continued asthma model group: nebulized inhalation of OVA for 14 weeks after sensitization; histamine group: nebulized inhalation of OVA for 14 weeks after sensitization and histamine was added in the last 6 weeks; antagonist group: nebulized inhalation of OVA for 14 weeks after sensitization and histamine receptor antagonists were added in the last 6 weeks. For each group, the concentration of histamine, sodium ion (Na(+)), chlorine ion (Cl(-)), arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), pH, actual bicarbonate (AB), standard bicarbonate (SB) in serum, and thickness of airway mucosa, base membrane and smooth muscle were measured and compared with each other. The results showed that: (1) the concentration of histamine in serum and the thickness of airway increased, the following order was, the control group, the asthma model group, the continued asthma model group and histamine group (P<0.01); and the concentration of histamine in serum and the thickness of airway of antagonist group was lower than that of the continued asthma model group (P<0.05, 0.01). (2) PaO2 of the asthma model group was lower than that of the normal control group (P<0.01); PaO2, pH, AB, SB decreased, the following order was, the asthma model group, the continued asthma model group and the histamine group (P<0.01); and PaO2, pH, AB, SB of the antagonist group was higher than that of the continued asthma model group (P<0.01); but for PaCO2, the order was converse (P<0.01); For the concentration of Na(+) and Cl(-) in serum, there was no difference among these groups. It is concluded that: (1) Histamine is one of the mediators in the airway remodeling of asthma. (2) Histamine receptor antagonists may play a role in preventing and treating airway remodeling. (3) There is a negative correlation between the PaO2, pH and the wall thickness of the airway (P<0.01), while a positive correlation between the PaCO2, anion gap (AG) and the wall thickness of the airway (P<0.01).

[Correlation between APOA gene polymorphism and intracranial aneurysm].

OBJECTIVE: To study the correlation between a pentanucleotide repeats (PNR) polymorphism of APOA and the genesis of intracranial aneurysm. METHODS: Fifty-eight patients with intracranial aneurysms diagnosed by angiography and 58 healthy controls were enrolled in our study. The gene polymorphism of APOA PNR were detected by polymerase chain reaction (PCR) and non-denatured polyacrylamide gels electropherosis (PAGE). RESULTS: Eight kinds of gene types and 6 kinds of alleles were found in these two groups. There were two sites of sequence variance in the 5' control region of APOA gene, which were significantly different between the patients and controls. CONCLUSION: Correlation may exist between intracranial aneurysm and APOA gene.

[Polymorphisms in the apolipoprotein A5 gene and apolipoprotein C3 gene in patients with coronary artery disease].

OBJECTIVE: To investigate the association between the -1131T/C and 56C/G polymorphism in the APOA5 gene as well as the -482C/T in the APOC3 gene and susceptibility to coronary artery disease (CAD) in a Chinese Han population. METHODS: Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polyacrylamide gel electrophoresis (PAGE) methods, we analyzed the genotypes in 312 CAD patients diagnosed by angiography and 317 healthy controls. The levels of serum lipid profiles were also studied by biochemical methods. RESULTS: The frequency of the APOA5 -1131 C allele in CAD patients was significantly higher than that of the control group (39.9% vs. 33.3%, P = 0.02). Compared with the wild type TT, CC homozygotes had a significantly increased CAD risk (OR = 1.93 and OR = 1.80 using unadjusted and adjusted logistic regression models, respectively). This association still existed after adjustment for the APOC3-482 variant. The APOA5-1131C allele also showed a correlation with increasing plasma TG levels (P < 0.01). CONCLUSIONS: The APOA5-1131T/C polymorphism but not APOC3-482C/T might contribute to an increased risk of CAD among Chinese accompanied by an elevation of serum TG levels; this effect was found to be independent of the APOC3-482C/T variant.

RhCG is downregulated in oesophageal squamous cell carcinomas, but expressed in multiple squamous epithelia.

To better understand the molecular events underlying the development of oesophageal cancer, we have isolated the genes dysregulated in primary oesophageal cancer tissues using a modified differential display polymerase chain reaction (DD-PCR). In the present study, a gene designated C15orf6 was identified. The C15orf6 gene, encompassing 25 kb, is composed of 11 exons with a mRNA of 1948 bp. Database searching showed that C15orf6 was 100% homologous to the Rh type C-glycoprotein (RhCG) with the same open reading frame, but 16 bp longer than RhCG at the 5'-end. The gene was highly expressed in human oesophagus, cervix, oral cavity, skin and kidney, but undetectable in the other 14 adult normal tissues examined. Northern blot, RT-PCR and western blot analysis showed that RhCG/C15orf6 was frequently lost or dramatically reduced in primary oesophageal cancer tissues (30/34) compared with the corresponding normal oesophageal mucosa. Three oesophageal-cancer cell lines tested lacked RhCG/C15orf6 expression. Immunohistochemistry revealed that in normal oesophageal tissues, RhCG/C15orf6 was mainly expressed in the plasma membrane of the epithelial cells. In addition, Rh-associated glycoprotein (RhAG) expression was also commonly silenced in both oesophageal cancer cell lines (2/3) and primary oesophageal cancer tissues (11/13). To our knowledge, this is the first time that RhAG expression has been seen in oesophageal epithelium and extends the functional role of the RhAG protein beyond the erythrocyte. These data suggest that inactivation of RhCG/C15orf6 and RhAG occurs frequently during the development of human oesophageal cancer.

Expression of MRP14 gene is frequently down-regulated in Chinese human esophageal cancer.

Migration inhibitory factor-related protein 14 (MRP14) is one of calcium-binding proteins, referred as S100A9. The heterodimeric molecule formed by MRP14 with its partner MRP8 (S100A8) is the major fatty acid carrier in neutrophils. The MRP8/14 complex has been also implicated in the intracellular transport of arachidonic acid and its precursors in keratinocytes. We show here the involvement of MRP14 in human esophageal cancer. In an initial study, mRNA differential display-reverse transcription polymerase chain reaction (DD-PCR) was performed with two esophageal carcinomas, one esophageal adenocarcinoma and matched normal adjacent mucosa. DD-PCR with the arbitrary primer OPA3 showed that one cDNA band was highly expressed in normal tissues, but disappeared or substantially decreased in tumor counterparts. It was later identified to be the 3'-end of migration inhibitory factor-related protein 14 (MRP14). Northern blotting, RT-PCR and Western blotting corroborated the down-regulation of MRP14 in 58/64 squamous cell carcinomas and 2/2 adenocarcinomas as compared with adjacent normal epithelia of the esophagus. MRP14 was undetectable in 3/3 esophageal-carcinoma cell lines. Immunochemistry demonstrated that expression of MRP14 was restricted to normal esophageal epithelia. No mutation was found in the genomic DNA of the MRP14 gene by PCR and directed DNA sequencing. Our finding suggested that the reduction of MRP14 expression is a frequent event in Chinese human esophageal cancer.

Allelic loss on 13q in esophageal squamous cell carcinomas from northern China.

Allelic loss on chromosome 13 occurs frequently in esophageal squamous cell carcinomas. To define minimal deletion intervals and find candidate tumor suppressor gene(s), we conducted a study of loss of heterozygosity (LOH) in 59 esophageal squamous cell carcinomas from northern China using a panel of ten microsatellite markers on chromosome 13q. The results showed that 12 of 59 (20%) cases presented allelic loss in three or more consecutive adjacent chosen markers, suggesting loss of larger fragments on chromosome 13q. Two minimal deletion regions of overlap were found: one was located on band 13q12.3 from markers D13S171 to D13S267, and the other on band 13q14.1-q14.3 from markers D13S263 to D13S168. The latter was a new deletion region that was never reported in esophageal squamous cell carcinomas. More frequent LOH was observed in higher pathological grade of esophageal cancer at loci D13S171, D13S263 and in later stage of esophageal cancer at D13S263. The data suggest the possibility that one or more unknown tumor suppressor gene(s) on 13q may play an important role in the development of esophageal squamous cell carcinomas.

Studies on the Separation, Purification of Beijing Duck Apo A-I CNBr Cleavaged Fragments and the Localization of Their Function Domain.

Apo A-I of Beijing duck was first cleavaged by CNBr into 11 peptide fragments which were further separated and purified by preparative SDS-PAGE and HPLC, then their molecular weights and N-terminal amino acid sequences were also determined. According to the molecular weights and N-terminal amino acid sequences of each fragment the positions of peptide fragments 3-10 in apo A-I molecule were localized at the sites of amino acid sequences 64-240, 74-240, 64-206, 1-163, 1-36, 171-206, 207-240 and 137-170 respectively. The studied results of their main functions are as following: (1) All the fragments could combine with lipids to form lipsomes of various sizes. The fragment Longer, the size will be larger. (2) The ability of the fragments 3-10 to activate LCAT equals to 65%, 52%, 60%, 39%, 8%, 7%, 0% and 2% of that of the whole apo A-I molecule respectively, showing that the activating sequence is localized in amino acid residues 64-136. (3) Only the liposomes formed with fragments 3, 4 and 9 could combine with the HDL receptor of liver cell membrane of Beijing duck; the rest of the liposomes demonstrated essentially no binding ability. As peptide fragments 3 and 4 also contained fragment 9, the result indicated that amino acids 207-240 maybe the fragment that combined with HDL receptor.