SEARCH · PubMed Health

Results for “Protein expression”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources

PubMed1997

Altered retinoblastoma protein expression in nonsmall cell lung cancer: its synergistic effects with altered ras and p53 protein status on prognosis.

BACKGROUND: Inactivation of the retinoblastoma (Rb) gene has been documented in various types of cancer, including lung cancer. Alterations of the p53 and ras genes are also common features in the molecular biology of lung carcinoma, and the authors of this article have reported previously on the prognostic significance of both of them. In the present study, the authors evaluated the prognostic significance of the loss of Rb protein expression alone, then performed a combined analysis of Rb protein and ras p21 status (Rb/ras) as well as an analysis of Rb and p53 protein status (Rb/p53) in patients with nonsmall cell lung cancer (NSCLC). METHODS: Ninety-one patients with NSCLC underwent potentially curative resection between 1977 and 1988, 65 of whom received postoperative combination chemotherapy. Tumor specimens were analyzed for Rb protein expression by immunohistochemistry. Univariate and multivariate analyses were performed to assess the association between Rb protein expression and survival. RESULTS: Nineteen (21%) of the 91 NSCLCs showed negative Rb protein expression. Positive or negative Rb protein expression (Rb+ or Rb-) as an individual factor was not statistically correlated with survival or prognosis in this cohort of NSCLC patients, although a tendency among Rb- patients to do worse was observed. The authors then combined the Rb protein status with previously studied results of ras p21 and p53 protein expression in the same tumor specimens, and compared the prognosis between the individuals with theoretically the best pattern of gene expression in their tumors and those with theoretically the worst pattern of expression, i.e., Rb+/ras- versus Rb-/ras+ and Rb+/p53- versus Rb-/p53+. In patients with adenocarcinoma, those with Rb-/ras+ tumors survived for a significantly shorter period after surgery (13% 5-year survival) than those with Rb+/ras- tumors (82% 5-year survival) (P = 0.01). Similarly, patients with Rb-/p53+ tumors survived for a significantly shorter period (20% 5-year survival) compared with those who had Rb+/p53- tumors (73% 5-year survival) (P = 0.008). Rb/ras status was a significant prognostic factor (P = 0.02 by univariate analysis, P = 0.048 by multivariate analysis), and Rb/p53 status tended to be significant as a prognostic factor (P = 0.04 by univariate analysis, P = 0.08 by multivariate analysis). In patients with squamous cell carcinoma, neither Rb/ras nor Rb/p53 status was a significant prognostic factor in this cohort. CONCLUSIONS: These results suggest that combined immunohistochemical analyses of Rb and ras p21 proteins and of Rb and p53 proteins may indicate their potentially synergistic effects on survival and prognosis. These analyses may also be useful for stratifying patients with adenocarcinoma of the lung into different prognostic groups and identifying populations with different risks of recurrence. Larger prospective studies with Stage I NSCLC patients are necessary to confirm the current findings.

Adenocarcinoma↗

PubMed2006

Nicotine withdrawal increases body weight, neuropeptide Y and Agouti-related protein expression in the hypothalamus and decreases uncoupling protein-3 expression in the brown adipose tissue in high-fat fed mice.

Nicotine is known to decrease body weight in normal rodents and human smokers, whereas nicotine withdrawal or smoking cessation can increase body weight. We have found that mice fed a high fat diet do not show the anorectic effect of chronic nicotine treatment, but do increase their body weight following nicotine withdrawal. Nicotine withdrawal is accompanied by increased expression of the orexigenic peptides neuropeptide Y and Agouti-related protein in the hypothalamus, and decreased expression of the metabolic protein uncoupling protein-3 in brown adipose tissue. These data suggest that diet can influence the ability of nicotine to modulate body weight regulation and demonstrate that chronic nicotine exposure results in adaptive changes in central and peripheral molecules which regulate feeding behavior and energy metabolism.

Adipose Tissue, Brown↗

PubMed2000

Prion protein expression in mammalian lenses.

PURPOSE: Aging and oxidative stress resulting from over-expression of Alzheimer precursor protein (betaAPP) have been studied as important factors contributing to the major age-related (sporadic), and minor (hereditary) forms of Alzheimer's disease (AD), and muscle inclusion body myositis, (IBM). AD and prion proteins accumulate in plaques linked with AD and scrapie diseases, and in rimmed vacuoles of IBM. Soluble beta-amyloid (Abeta) fibrillar forms are now thought to play a critical role in and outside of cells by producing oxidative stress. In lens, betaAPP and Abeta increase in cultured lenses exposed to oxidative stress, and in areas of lens fiber cell degeneration in thiamine (vitamin B1) deprived mice, a classic model of systemic oxidative stress. The purpose of the present study is to extend our studies of amyloid disease-related protein expression in mammalian lenses. METHODS: Western blot, immunohistochemical detection, and RT-PCR methods were used to identify and quantitate prion protein expression in human, monkey, and guinea pig lenses. RESULTS: We demonstrate for the first time that prion protein gene expression increases with oxidative stress in cultured human lens epithelial cells. In addition, we detected greater prion protein gene expression in fiber cells than epithelial cells in vivo. This is consistent with increases in prion protein expression demonstrated in myoblasts and neuronal cells induced to differentiate. Our initial investigations of prion protein in human lens cataracts identified increased prion protein immunoreactivity in regions of lens fiber cell degeneration. CONCLUSIONS: The present data indicate that prion protein expression increases during lens development, and is substantially increased in cultured human lens epithelial cells exposed to oxidative stress. We also provide evidence that prion protein immunoreactivity can be increased in regions of fiber cell disorganization. These data suggest a potential role for prion protein as a marker for some types of lens pathology, and in the mechanism of oxidative stress-related lens degeneration.

Animals↗

PubMed2004

Cellular stress-related protein expression in Helicobacter pylori-infected gastric epithelial AGS cells.

Helicobacter pylori infection leads to gastroduodenal inflammation, peptic ulceration, and gastric carcinoma. Moreover, H. pylori may induce disease-specific protein expression in gastric epithelial cells. The present study was aimed at determining differentially expressed proteins in H. pylori-infected gastric epithelial AGS cells. AGS cells were treated with H. pylori at a bacterium/cell ratio of 300:1 for 12 h. Altered protein patterns as separated by two-dimensional electrophoresis using pH gradients of 4-7 were conclusively identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis of the peptide digests. Four differentially expressed proteins, whose expression levels were increased by more than two-fold in H. pylori-infected cells, were analyzed. These proteins (14-3-3 protein alpha/beta, cullin homolog 3, alpha-enolase, ezrin) are known to be related to cell proliferation, cell adhesion, and carcinogenesis, and may be mediated by cellular stress, such as reactive oxygen species. In conclusion, the identification of these differentially expressed proteins provide valuable information for the understanding of the pathophysiologic mechanisms of H. pylori-induced gastric diseases, and may be useful as prognostic indices of H. pylori-related gastric disorders.

Cell Line, Tumor↗

PubMed1996

Secretory component mRNA and protein expression in colorectal adenomas and carcinomas.

Secretary component (SC) is expressed basolaterally as a transmembrane protein (pIg receptor) on secretory epithelial cells. As pIg receptor it plays a central role in humoral immunity by mediating the external translocation of dimeric IgA and pentameric IgM. A few case reports have suggested that reduced or absent SC protein expression is associated with diarrhoeal disease, but there is no convincing evidence that a primary pIg receptor deficiency can occur. In this study the relative presence of SC mRNA was determined by Northern blot analysis and related to immunohistochemically determined SC protein expression in 33 colorectal adenomas (31 patients) with increased risk of developing sporadic colorectal cancer, as well as in 19 colorectal carcinomas from 19 patients with such sporadic tumours. In the adenomas, SC mRNA levels were positively related to SC protein expression; both mRNA and SC protein were negatively related to histological grade. Similarly, SC mRNA levels tended to be related to the SC protein expression in the carcinomas. SC mRNA was detected in all adenomas, and only two of ten carcinomas (10.5%) deemed to be SC deficient by immunohistochemistry also lacked SC mRNA expression, suggesting diallelic alterations in the SC-encoding gene (locus PIGR). This possibility agreed with Southern blot analysis performed on a separate sample of 32 other colonic carcinomas in which the diallelic loss of D1S58 (which exhibits a close linkage centromerically to PIGR) was calculated to be 6.4%. Together these findings suggested that reduced SC protein expression in colorectal adenomas might be a transcriptional defect reflecting the degree of cellular dysplasia, whereas absent SC protein expression in colorectal carcinomas might also involve post-transcriptional defects and occasional diallelic gene deletions representing late events in carcinogenesis.

Adenoma↗

PubMed1992

Immunoreactivity of recombinant carcinoembryonic antigen proteins expressed in Escherichia coli.

Immunoreactivities of recombinant carcinoembryonic antigen (CEA) proteins expressed in Escherichia coli (E. coli) were analyzed in relation to the CEA domain structure [domains N, I (A1-B1), II (A2-B2), III (A3-B3) and M]. We reconstructed in a prokaryotic expression vector, pUCPL-cI, the cDNAs fro CEA-N, CEA-I, CEA-II, and CEA-III-M. The latter three were expressed as fusion products with bacterial beta-galactosidase. The recombinant proteins were solubilized by sonication in 1% sodium dodecyl sulfate (SDS) and purified by preparative SDS-polyacrylamide gel electrophoresis followed by electroelution. Their molecular weights judged from Western blotting coincided with those calculated from their cDNA sequences, respectively. By solid-phase enzyme immunoassays, the immunoreactivities of the purified recombinant proteins were tested with 21 distinct anti-CEA monoclonal antibodies (MAbs) which had been found to recognize the peptide epitopes of the CEA molecule and to be reactive with the recombinant CEA proteins expressed in Chinese hamster ovary (CHO) cells. Fourteen of the 21 MAbs reacted with the recombinant CEA proteins expressed in E. coli and confirmed the localization of the epitopes identified by using the recombinant CEA proteins expressed in CHO cells. The reactivities of 5 MAbs with the recombinant proteins expressed in E. coli were remarkably low when compared with those of the proteins expressed in CHO cells but also confirmed the localization of the epitopes identified with the recombinant CEA proteins expressed in CHO cells. The remaining 2 MAbs did not react with any recombinant protein expressed in E. coli. These results indicate that the fusion CEA-proteins expressed in E. coli are useful in the localization of the epitopes on the polypeptide chains when they reacted with the MAbs tested. However, one third of the epitopes of CEA peptides may be profoundly affected by the presence of disulfide bonds and/or sugar chains which do not seem to be formed well in E. coli.

Base Sequence↗

PubMed1997

Effects of preconditioning with ebselen on glutathione metabolism and stress protein expression.

Selenium induces several proteins, including glutathione and stress proteins. These proteins have been shown to be cardioprotective against oxidative injury. To determine whether ebselen, a seleno-organic compound, can also induce these proteins and exert cardioprotective action, we examined the effects of preconditioning with ebselen on glutathione metabolism and stress protein expression and on myocyte injury induced by oxidative stress. Treatment of cultured cardiac myocytes with ebselen (0.3-30 microM) for 24 hr increased the reduced glutathione content. Glutathione reductase activity, but not glutathione peroxidase activity, was significantly elevated in a dose-dependent manner. Pretreatment with ebselen increased the expression of such stress proteins as heat shock protein 70 and heme oxygenase-1 (heat shock protein 32) in cardiac myocytes, as assessed by Western blotting. Expression of heat shock protein 70 was increased only at a higher dose of ebselen (30 microM), whereas expression of heme oxygenase-1 was markedly increased at a lower dose of ebselen (3 microM). Under these conditions, the myocyte injury induced by hydrogen peroxide or simulated ischemia/reperfusion, assessed by the release of lactate dehydrogenase into the culture medium, was reduced by ebselen pretreatment in a dose-dependent manner. Results indicated that cardiac myocytes pharmacologically preconditioned with ebselen for 24 hr exhibited resistance to oxidative injury, possibly via the up-regulation of glutathione metabolism and the expression of stress proteins.

Animals↗

PubMed2006

High-throughput analysis of GST-fusion protein expression and activity-dependent protein interactions on GST-fusion protein arrays with a spectral surface plasmon resonance biosensor.

We modified gold arrays with a glutathione (GSH) surface, and investigated high-throughput protein interactions with a spectral surface plasmon resonance (SPR) biosensor. We fabricated the GSH exterior on gold surfaces by successive modification with aminoethanethiol, 4-maleimidobutyric acid N-hydroxysuccinimide ester and GSH. We immobilized GST-Rac1, GST-RhoA, the GST-Rho-binding domain of rhotekin and the GST-p21-binding domain of PAK1 onto the GSH surface, and observed specific antigen-antibody interactions on the GST-fusion protein arrays. We determined the expression of GST-fusion proteins in Escherichia coli on the GSH surface with the SPR biosensor. We then analyzed the interactions of tissue transglutaminase (tTGase), a Ca2+-dependent enzyme, with RhoA and Rac1 on the GST-fusion protein arrays with the SPR biosensor. We found that tTGase interacted with RhoA and Rac1 in a Ca2+-dependent manner, indicating that the interactions were dependent on tTGase activity. In addition, transamidation of Rac1 by tTGase was dependent on Ca2+ concentration. We obtained similar results with GST pull-down assays. Thus, protein arrays prepared on the GSH surface provide a useful system for the high-throughput analysis of GST-fusion protein expression and activity-dependent protein interactions with the spectral SPR biosensors.

Apoptosis Regulatory Proteins↗

PubMed2001

[The protein expression of Bcl-x1 and Bcl-2 in eosinophils in nasal polyps and the influence of beclomethasone dipropionate on the expression].

OBJECTIVE: To investigate the protein expression of B-cell lymphoma/leukemia-2(Bcl-2) and B-cell lymphoma/leukemia-x long(Bcl-x1) in eosinophils in nasal polyps and the influence of beclomethasone dipropionate on the expression. METHODS: Using May-Grünwald-Giemsa (MGG) method and immunohistochemical method, the protein expression of Bcl-x1 and Bcl-2 in eosinophils in nasal polyps from patients treated with beclomethasone dipropionate treatment and patients without any treatment was compared. RESULTS: (1) Nasal polyp tissues from patients without treatment had more eosinophils than those from patients with treatment(P < 0.01). (2) No protein expression of Bcl-2 was observed in all 52 patients. (3) 20.0% patients with treatment had the expression of Bcl-x1, whereas 48.1% patients without treatment had the expression. The difference between these two groups was significant(P < 0.05). CONCLUSION: These data suggest that Bcl-x1 may act as an anti-apoptotic molecule in eosinophils and corticosteroids induce eosinophil apoptosis through suppressing the expression of Bcl-x1.

Adolescent↗

PubMed2003

Time course of GLUT4 and AMPK protein expression in human skeletal muscle during one month of physical training.

UNLABELLED: Endurance training elicits profound adaptations of skeletal muscle, including increased expression of several proteins. The 5'-AMP activated protein kinase (AMPK) may be one of these, considering the fact that acute exercise increases AMPK activity. Eight young (26 +/- 1 year) lean, healthy males endurance trained one leg (while the other leg remained resting) on an ergometer bicycle for 30 min/day for four weeks (workload corresponding to approximately 70% of maximal oxygen uptake). Muscle biopsies were obtained approximately 18 h after the previous training session. On day eight GLUT4 protein expression was 36% higher in trained (T) compared with untrained (UT) (P < 0.05), but no further increase was seen at day 14 and 30 despite continuously increasing absolute workloads. Expression of AMPKalpha2 and actin did not change with training. In contrast, expression of AMPKalpha1 was 27% higher in T vs. UT muscle (P < 0.05) (measured only on day 30). CONCLUSIONS: GLUT4 protein expression increases substantially after seven days of endurance training with no further increase with prolonged training at progressively increasing workloads. AMPKalpha1 and alpha2 behave differently in their expression in response to endurance training. AMPKalpha1 protein content is increased after one month of training, while no change in AMPKalpha2 and actin expression was detected over the time course of the training period.

AMP-Activated Protein Kinase Kinases↗

PubMed2004

Impact of thyroid hormone deficiency on the developing CNS: cerebellar glial and neuronal protein expression in rat neonates exposed to antithyroid drug propylthiouracil.

The developing rat cerebellum is vulnerable to thyroid hormone (TH) deficiency. The present study addresses the molecular mechanisms involved in this response. Specifically, the study focuses on the expression of selected cerebellar proteins that are known to be directly [protein expressing 3-fucosyl-N-acetyl-lactosamine antigen (CD15), neuronal cell adhesion molecule (L1)] or indirectly [glial fibrillary acidic protein (GFAP)], involved in glial-neuronal interactions and thus regulation of cell proliferation and granule cell migration. Cerebellar mass, structure, and protein expression in rat neonates exposed to antithyroid drug propylthiouracil (PTU) from the embryonic day (E) 16 to postnatal day (P) 21 were compared against rat neonates that received replacement of thyroxin (T4) starting on day P1 or untreated controls. Cerebellar proteins were analyzed by quantitative Western blots. PTU-treated rats lagged in growth and showed reduction in cerebellar mass and alterations in cerebellar structure on P15. Daily treatment of neonates with T4 restored normal cerebellum-to-body-mass ratio, cerebellar structure, and cerebellar protein expression. Densitometric analysis of Western blots revealed altered expression of selected proteins in the cerebella of hypothyroid neonates. A decrease of CD15 (46%, p = 0.031) was observed on P10 and was accompanied by a decrease in GFAP expression (64%, p = 0.039). Furthermore, a shift in the developmental GFAP profile was observed in the PTU-treated cerebellum. L1 expression was not significantly affected in the hypothyroid cerebellum. Altered expression of cerebellar proteins is likely to affect cell-cell interactions and consequently cell proliferation and migration and contribute to structural and functional alterations seen in the hypothyroid rat neonates.

Age Factors↗

PubMed1998

Expressed protein ligation, a novel method for studying protein-protein interactions in transcription.

Expressed protein ligation is a novel protein semi-synthesis method that permits the in vitro ligation of a chemically synthesized C-terminal segment of a protein to a recombinant N-terminal segment fused through its C terminus to an intein protein splicing element. In principle, the practical convenience of this method, combined with the expanded opportunities in protein engineering that it provides, makes it well suited for probing the molecular basis of complex processes such as transcription. Here we describe the successful application of expressed protein ligation to the approximately 600 amino acid sigma70 subunit of Escherichia coli RNA polymerase. The resulting semi-synthetic sigma70 constructs are shown to be fully functional and have been used to map the binding region of the bacteriophage T4 anti-sigma protein, AsiA, to within amino acids 567-600 of sigma70. The success of these semi-synthesis studies sets the stage for the future generation of semi-synthetic sigma70 molecules in which unnatural amino acids and biophysical probes are site-specifically incorporated in the RNA polymerase complex.

Bacterial Proteins↗

PubMed2005

DEPD: a novel database for differentially expressed proteins.

SUMMARY: The Differentially Expressed Protein Database was designed to store the output of comparative proteomics studies and provides a publicly available query and analysis platform for data mining. The database contains information about more than 3000 differentially expressed proteins (DEPs) manually extracted from the published literature, including relevant biological, experimental and methodological elements. Tools for visualization and functional analysis of DEPs are provided via a user-friendly webinterface. AVAILABILITY: http://protchem.hunnu.edu.cn/depd/.

Computational Biology↗

PubMed2005

Sex differences in Fos protein expression in the neonatal rat brain.

Sex differences in the brain and behaviour are mostly a result of transient increases in testosterone during the perinatal period. Testosterone influences brain development primarily through aromatization to oestradiol and subsequent binding to oestrogen receptors. Although some studies report that steroid hormones regulate the expression of the inducible transcription factor, Fos, in developing brain, it is not known if there is a sex difference in Fos expression. Changes in Fos protein can be used as an indicator of neuronal/genomic activity. Thus, it provides a useful tool to identify brain regions responding directly or indirectly to steroid hormones. In a first experiment, we examined Fos protein expression in the developing male and female rat brain using western immunoblotting. Dissections were taken from male and female rat pups on the day of birth (postnatal day 0; PN 0), PN1, PN5, PN11 or PN20. Although there was no difference on PN 0, males expressed significantly greater levels of Fos protein on PN1, PN5 and PN20. In a second experiment, we localized the sex difference in Fos protein expression using immunocytochemistry. We found that males expressed significantly higher levels of Fos within a variety of brain regions. These data indicate a sex difference in Fos protein expression during brain development, suggesting a potential role for Fos in differentiating male from female rat brain.

Age Factors↗

PubMed2005

CYP3A7 protein expression is high in a fraction of adult human livers and partially associated with the CYP3A7*1C allele.

Previously, cytochrome P450 3A7 (CYP3A7), which constitutes the major CYP enzyme in fetal livers, has been considered a fetus-specific enzyme. However, CYP3A7 mRNA has recently been shown to be expressed at significant levels in a subset of adult human livers, several of which carry the CYP3A7*1C allele that contains the proximal PXR/CAR element of CYP3A4. The objective of this study was to investigate CYP3A7 expression at the protein level by developing a CYP3A7-specific antibody to allow its quantification. Based on results from 59 adult human liver samples, we found significant CYP3A7 protein expression in approximately one in 10 adult livers amounting for 24-90 pmol/mg microsomal protein, thereby contributing 9-36% to total CYP3A levels in these livers. CYP3A7 protein was detected in five of seven livers carrying the CYP3A7*1C allele (two of which only had trace amounts), whereas an additional three livers expressing CYP3A7 were apparently homozygous for CYP3A7*1. The mean protein expression level of CYP3A7 was 42 pmol/mg within the group of livers expressing CYP3A7 and 4 pmol/mg in all liver samples. CYP3A7 expression was thus higher than that of the polymorphically expressed CYP3A5 in adult human livers, based on a comparison with a previous study using our CYP3A5 peptide-specific antibody. The relatively high level of CYP3A7 protein expression detected in a subset of adult livers may be relevant with respect to the metabolism of exogenous and endogenous substrates, such as retinoic acid and dehydroepiandrosterone.

Adjuvants, Immunologic↗

PubMed2005

Low birthweight is associated with specific changes in muscle insulin-signalling protein expression.

AIMS/HYPOTHESIS: People with low birthweight have an increased risk of developing type 2 diabetes mellitus in adulthood. The mechanistic basis of this phenomenon is not known. Here we investigate the effect of early growth restriction on the expression of insulin-signalling proteins in skeletal muscle in a human cohort and a rat model. METHODS: We recruited 20 young men with low birthweight (mean birthweight 2702+/-202 g) and 20 age-matched control subjects (mean birthweight 3801+/-99 g). Biopsies were obtained from the vastus lateralis muscle and protein expression of selected insulin-signalling proteins was determined. Rats used for this study were male offspring born to dams fed a standard (20%) protein diet or a low (8%) protein diet during pregnancy and lactation. Protein expression was determined in soleus muscle from adult offspring. RESULTS: Low-birthweight subjects showed reduced muscle expression of protein kinase C (PKC)zeta, p85alpha, p110beta and GLUT4. PKCzeta, GLUT4 and p85 were also reduced in the muscle of rats fed a low-protein diet. Other proteins studied were unchanged in low-birthweight humans and in rats fed a low-protein diet when compared with control groups. CONCLUSIONS/INTERPRETATION: We found decreased expression of specific insulin-signalling proteins in low-birthweight subjects compared to controls. These changes precede the onset of impaired glucose tolerance. The similarity of protein expression profile in the men with low birthweight compared to that of the offspring of rats fed a low-protein diet suggests that the rodent model is an accurate representation of the human situation. It also provides a potential mechanistic explanation as to why the fetal environment plays an important role in determining risk of developing type 2 diabetes.

Adult↗

PubMed2000

Protein expression of bax, bcl-2, and p53 in patients with non-Hodgkin's gastric lymphoma: prognostic significance.

The biologic significance of bcl-2, bax, and p53 gene expression in patients with non-Hodgkin's gastric lymphoma is unknown. We examined the prognostic value of these genes in 36 patients with gastric lymphoma treated in our clinic between 1990 and 1995. Paraffin-embedded specimens from 36 patients who underwent primary resection of the stomach for gastric lymphoma were analyzed immunohistochemically for p53, bax, and bcl-2 gene expression. Expression of bax was seen in 24 of 36 patients (66.7%), p53 expression was found in 8 of 36 tumors (22.2%), and bcl-2 cytoplasmic staining was detected in 6 of 36 patients (16.7%). We performed a univariate analysis to examine the possible correlation between the expression of these genes and the survival of our patients. Expression of bax protein proved to be a statistically significant prognostic factor (p = 0.049). Protein expression of p53 and bcl-2 did not statistically correlate with survival. In the bcl-2-negative (-) patient group (30 patients), those who were bax-positive had a statistically significant better survival than those who were bax-negative (63.3% vs. 36.7%, p = 0.03). There was also a statistically significant correlation between p53 expression and the grade of the tumor (p = 0.0014). P53 protein expression increased along with the grade. Expression of bax is a significant prognostic factor in patients with gastric lymphoma. Its prognostic value increases significantly when studied in bcl-2-negative patients; but expression of bax failed to be an independent prognostic factor. Expression of bcl-2 and p53 has no prognostic significance. Expression of p53 seems to represent a marker for loss of differentiation.

Adult↗

PubMed1981

Effects of pyridoxine on serum protein expression in hepatoma-bearing rats.

The effect of pyridoxine depletion on the expression of serum protein species in control and Morris hepatoma No. 7777-bearing rats was studied with polyacrylamide gel electrophoresis (PAGE). A group of 20 Buffalo female rats was fed ad libitum a complete diet lacking pyridoxine, whereas a similar group was fed the same diet with pyridoxine. After a 22-day feeding period, 12 animals from each group were inoculated with hepatoma No. 7777 cells in the thigh muscles of both hind legs and allowed to grow for 25 days. Sera were obtained from all animals by heart puncture under light ether anesthesia, and protein species were resolved by PAGE. Eight and four protein bands in the haptoglobin and postalbumin regions, respectively, were resolved from control rat serum, whereas sera from depleted animals had eight and three bands, respectively. Protein expression was facilitated by the presence of hepatomas. Ten and six protein bands were seen in the haptoglobin and postalbumin regions, respectively, upon PAGE of sera from control tumor-bearing rats. A positive synergistic effect between pyridoxine lack and tumor presence was also found. Twelve and five bands were resolved in the haptoglobin and postalbumin regions, respectively, when sera from pyridoxine-depleted tumor-bearing rats were electrophoresed. These results showed that vitamin B6, in addition to its well-known coenzymatic function, exercised a type of control over protein expression, which may be positive or negative depending on the nutritional and health status of the animal.

Animals↗