[Formulation possibilities of self-emulsifying drug deliv- ery systems, microemulsions and nanoemulsions.] / Not available.

Objective The aim of this review is to introduce the self-emulsifying drug delivery systems which can be used to improved the bioavailability of poorly water soluble drug substances. Methods The review summarizes the most prominent results of the lipid based medicinal preparations, such as microemulsions and nanoemulsions developed in the last two decades. Results The analysis of the references details the lipid based formulation classification systems, the most common excipients, the quality attributes depending on the ingredients, as well as the differences in the characteristics of micro- and nanoemulsions. Conclusions The summary demonstrates the formulation possibilities of self-emulsifying drug delivery systems, which may increase the applicability and are promising to improve the therapeutic effectiveness.

Non-invasive diagnosis of endometriosis based on a combined analysis of six plasma biomarkers.

BACKGROUND: Lack of a non-invasive diagnostic test contributes to the long delay between onset of symptoms and diagnosis of endometriosis. The aim of this study was to evaluate the combined performance of six potential plasma biomarkers in the diagnosis of endometriosis. METHODS: This case-control study was conducted in 294 infertile women, consisting of 93 women with a normal pelvis and 201 women with endometriosis. We measured plasma concentrations of interleukin (IL)-6, IL-8, tumour necrosis factor-alpha, high-sensitivity C-reactive protein (hsCRP), and cancer antigens CA-125 and CA-19-9. Analyses were done using the Kruskal-Wallis test, Mann-Whitney test, receiver operator characteristic, stepwise logistic regression and least squares support vector machines (LSSVM). RESULTS: Plasma levels of IL-6, IL-8 and CA-125 were increased in all women with endometriosis and in those with minimal-mild endometriosis, compared with controls. In women with moderate-severe endometriosis, plasma levels of IL-6, IL-8 and CA-125, but also of hsCRP, were significantly higher than in controls. Using stepwise logistic regression, moderate-severe endometriosis was diagnosed with a sensitivity of 100% (specificity 84%) and minimal-mild endometriosis was detected with a sensitivity of 87% (specificity 71%) during the secretory phase. Using LSSVM analysis, minimal-mild endometriosis was diagnosed with a sensitivity of 94% (specificity 61%) during the secretory phase and with a sensitivity of 92% (specificity 63%) during the menstrual phase. CONCLUSIONS: Advanced statistical analysis of a panel of six selected plasma biomarkers on samples obtained during the secretory phase or during menstruation allows the diagnosis of both minimal-mild and moderate-severe endometriosis with high sensitivity and clinically acceptable specificity.

Density of small diameter sensory nerve fibres in endometrium: a semi-invasive diagnostic test for minimal to mild endometriosis.

BACKGROUND: The aim of our study was to test the hypothesis that multiple-sensory small-diameter nerve fibres are present in a higher density in endometrium from patients with endometriosis when compared with women with a normal pelvis, enabling the development of a semi-invasive diagnostic test for minimal-mild endometriosis. METHODS: Secretory phase endometrium samples (n = 40), obtained from women with laparoscopically/histologically confirmed minimal-mild endometriosis (n = 20) and from women with a normal pelvis (n = 20) were selected from the biobank at the Leuven University Fertility Centre. Immunohistochemistry was performed to localize neural markers for sensory C, Adelta, adrenergic and cholinergic nerve fibres in the functional layer of the endometrium. Sections were immunostained with anti-human protein gene product 9.5 (PGP9.5), anti-neurofilament protein, anti-substance P (SP), anti-vasoactive intestinal peptide (VIP), anti-neuropeptide Y and anti-calcitonine gene-related polypeptide. Statistical analysis was done using the Mann-Whitney U-test, receiver operator characteristic analysis, stepwise logistic regression and least-squares support vector machines. RESULTS: The density of small nerve fibres was approximately 14 times higher in endometrium from patients with minimal-mild endometriosis (1.96 +/- 2.73) when compared with women with a normal pelvis (0.14 +/- 0.46, P < 0.0001). CONCLUSIONS: The combined analysis of neural markers PGP9.5, VIP and SP could predict the presence of minimal-mild endometriosis with 95% sensitivity, 100% specificity and 97.5% accuracy. To confirm our findings, prospective studies are required.

Endotoxins do not influence transplacental transmission of lymphotropic human herpesviruses and human papillomaviruses into amniotic fluid taken from healthy mothers before parturition in Hungary.

Pregnant women were examined following healthy pregnancies at term. Amniotic fluids were sampled before arteficial rupture of membranes using closed vacutainer system. Blood samples were also taken from the pregnants simultaneously. Endotoxin concentrations of amniotic fluids were tested by the semiquantitative Limulus amebocyte lysate. Both amniotic fluids and blood samples were tested for the presence of DNA of lymphotropic human herpesviruses. The DNA of human papillomaviruses were tested only in the amniotic fluid samples. One-third of the amniotic fluids tested were found to contain measurable amounts of endotoxin. Lymphotropic herpesvirus DNA was deteced in every fourth amniotic fluid sample and in every 8th blood sample. The prevalence of papillomaviruses was 7 of 96 samples. No significant correlation was found between the presence of endotoxin and viruses in the amniotic fluids. Epstein-Barr virus, human cytomegalovirus and human herpesvirus type 7 were found more frequently in the amniotic fluids than in blood samples (7 to 1). The prevalence of human herpesvirus 6 and 8 was higher in the blood samples than that in the amniotic fluids. The mean weight of the neonates were not impaired significantly by the presence of either viruses or endotoxin. Possible post partum consequences, i.e. partial immunotolerance to viruses is discussed.

Assessing crystallization droplets using birefringence.

In this paper, the detection of crystalline elements in protein crystallization droplets containing precipitate is illustrated using the rotating-polarizer microscope technique. The sensitivity of this automated birefringence technique enables the detection of microcrystals in a precipitate that appears to be amorphous using traditional methods of inspection. The technique is illustrated with lysozyme and glucose isomerase. Glucose isomerase microcrystals were used successfully for seeding experiments and the conditions of both of the systems were refined to produce crystals suitable for X-ray analysis. The results are relevant to the field of high-throughput crystallography as an automated crystal-detection method as well as being a useful tool for detailed precipitate analysis.

[The c-erbB-related oncoproteins in normal placenta and in gestational trophoblastic diseases (in vitro study)]. / A c-erbB családba tartozó onkofehérjék normális lepényben és terhességi trophoblast-betegségekben (in vitro vizsgálatok).

In this study the expression of epidermal growth factor receptor (EGFR) and c-erbB-2, c-erbB-3 and c-erbB-4 oncogenes were investigated in gestational trophoblastic diseases and normal first trimester placenta. Furthermore, the possibility that macrophage (IL-1 alpha, IL-1 beta, TNF) and lymphocyte (IL-2, gamma-IFN, GM-CSF) cytokines effects are mediated by changes in EGFR expression were studied. Paraffin sections of 16 cases of partial mole, 25 cases of complete mole, 10 cases of gestational choriocarcinoma and 11 cases of therapeutic abortion were studied immunohistochemically for EGFR, c-erbB-2, c-erbB-3 and c-erbB-4 proteins. The presence of EGFR mRNA was studied using in situ hybridization. JEG-3 human choriocarcinoma cells were incubated with varying concentrations of interleukin 1-alpha, interleukin 1-beta, interleukin 2, gamma-interferon, granulocyte-macrophage colony stimulating factor and tumor necrosis factor-alpha, and the expression of EGFR was measured by radioimmunoassay using a murine monoclonal antibody with specificity for EGFR. Staining for EGFR was detected immunohistochemically in all cell type in gestational trophoblastic diseases and normal placenta. The levels of expression of EGFR in choriocarcinoma and syncytiotrophoblasts and cytotrophoblasts in complete mole were significantly greater than those in syncytiotrophoblasts and cytotrophoblasts in both normal placenta and partial mole (p < 0.01, p < 0.01). The immunoreactivity of c-erbB-2 was significantly stronger in choriocarcinoma and extravillous trophoblast in complete mole than that in extravillous trophoblast in partial mole and normal placenta (p < 0.02, p < 0.01, respectively). Strong immunostaining for EGFR (p = 0.02) and c-erbB-3 (p < 0.01) in extravillous trophoblasts of complete mole was found to be significantly correlated with the development of persistent postmolar gestational trophoblastic tumor. Macrophage-derived cytokines IL-1 alpha, IL-1 beta and TNF significantly suppressed cell growth; this was associated with a significant increase in EGFR expression. The lymphocyte (IL-2, gamma-IFN, GM-CSF) cytokines had no significant effect on either EGFR expression or cell growth. These findings support the concept that cytokines may act as paracrine mediators of autocrine processes involved in choriocarcinoma cell growth regulation by modulating growth factor receptor expression. The EGFR-related family of oncogenes may be important in the pathogenesis and prognosis of gestational trophoblastic diseases.

High anti-paternal cytotoxic T-lymphocyte precursor frequencies in women with unexplained recurrent spontaneous abortions.

A number of cases of unexplained (idiopathic) recurrent spontaneous abortions may be attributable to immunological mechanisms. Several lines of evidence indicate that some immunocompetent effector cell populations play an important role in the pathogenesis of unexplained miscarriages. However a suitable method is lacking for defining an existing immunological background of recurrent spontaneous abortions. We tried to find a useful cellular immunological method, that is suitable for predicting the eventual immunological cause in the case of unexplained recurrent spontaneous abortions. We have examined the anti-paternal cytotoxic T-lymphocyte precursor frequencies by cell-mediated lympholysis and limiting dilution analysis in the peripheral blood of women with recurrent spontaneous abortions in order to reveal the functional role of this cell population in spontaneous abortions. An extremely high partner allo-antigen-specific cytotoxic T-lymphocyte precursor frequency was determined in the case of all those habitual aborters, where no other than an immunological cause could be responsible for the abortions. This phenomenon supports the important role of the T-lymphocytes in this disorder. We suggest that the immunological background of recurrent spontaneous miscarriages might be determined on the basis of a very high cytotoxic T-lymphocyte precursor frequency. This diagnostic test might be useful in selecting patients for immunotherapy.

Structures of prolyl oligopeptidase substrate/inhibitor complexes. Use of inhibitor binding for titration of the catalytic histidine residue.

Structure determination of the inactive S554A variant of prolyl oligopeptidase complexed with an octapeptide has shown that substrate binding is restricted to the P4-P2' region. In addition, it has revealed a hydrogen bond network of potential catalytic importance not detected in other serine peptidases. This involves a unique intramolecular hydrogen bond between the P1' amide and P2 carbonyl groups and another between the P2' amide and Nepsilon2 of the catalytic histidine 680 residue. It is argued that both hydrogen bonds promote proton transfer from the imidazolium ion to the leaving group. Another complex formed with the product-like inhibitor benzyloxycarbonyl-glycyl-proline, indicating that the carboxyl group of the inhibitor forms a hydrogen bond with the Nepsilon2 of His(680). Because a protonated histidine makes a stronger interaction with the carboxyl group, it offers a possibility of the determination of the real pK(a) of the catalytic histidine residue. This was found to be 6.25, lower than that of the well studied serine proteases. The new titration method gave a single pK(a) for prolyl oligopeptidase, whose reaction exhibited a complex pH dependence for k(cat)/K(m), and indicated that the observed pK(a) values are apparent. The procedure presented may be applicable for other serine peptidases.

Expression of epidermal growth factor receptor-related family products in gestational trophoblastic diseases and normal placenta and its relationship with development of postmolar tumor.

OBJECTIVE: The goal of this work was to study the expression of epidermal growth factor receptor (EGFR) and c-erbB-3 and c-erbB-4 oncogenes in gestational trophoblastic diseases and normal first-trimester placenta. STUDY DESIGN: Paraffin sections of 16 cases of partial mole, 25 cases of complete mole, 10 cases of gestational choriocarcinoma, and 11 cases of therapeutic abortion were studied immunohistochemically for EGFR, c-erbB-3, and c-erbB-4 proteins. The presence of EGFR mRNA was studied using in situ hybridization. RESULTS: Staining for EGFR was detected immunohistochemically in all cell types in gestational trophoblastic diseases and normal placenta. In situ hybridization for EGFR mRNA correlated with immunostaining for EGFR in all tissues studied. All 10 cases of choriocarcinoma exhibited strong immunoreactivity for EGFR. The levels of expression of EGFR in choriocarcinoma and syncytiotrophoblasts and cytotrophoblasts in complete mole were significantly greater than those in syncytiotrophoblasts and cytotrophoblasts in both normal placenta and partial mole (P < 0.01, P < 0.01). Expression of c-erbB-3 did not significantly differ among placental and gestational trophoblastic disease tissues and trophoblastic cell types except for significantly increased expression in choriocarcinoma as compared with cytotrophoblasts of partial mole (P = 0.02). The placenta, complete and partial mole, and choriocarcinoma tissues demonstrated similar immunoreactivity for c-erbB-4. Strong immunostaining for EGFR (P = 0.02) and c-erbB-3 (P < 0.01) in extravillous trophoblasts of complete mole was found to be significantly correlated with the development of persistent postmolar gestational trophoblastic tumor. CONCLUSION: The EGFR-related family of oncogenes may be important in the pathogenesis of gestational trophoblastic diseases. The increased expression of EGFR and c-erbB-3 in complete mole may also influence the development of persistent gestational trophoblastic tumor.

X-ray crystallographic study of cyanide binding provides insights into the structure-function relationship for cytochrome cd1 nitrite reductase from Paracoccus pantotrophus.

We present a 1.59-A resolution crystal structure of reduced Paracoccus pantotrophus cytochrome cd(1) with cyanide bound to the d(1) heme and His/Met coordination of the c heme. Fe-C-N bond angles are 146 degrees for the A subunit and 164 degrees for the B subunit of the dimer. The nitrogen atom of bound cyanide is within hydrogen bonding distance of His(345) and His(388) and either a water molecule in subunit A or Tyr(25) in subunit B. The ferrous heme-cyanide complex is unusually stable (K(d) approximately 10(-6) m); we propose that this reflects both the design of the specialized d(1) heme ring and a general feature of anion reductases with active site heme. Oxidation of crystals of reduced, cyanide-bound, cytochrome cd(1) results in loss of cyanide and return to the native structure with Tyr(25) as a ligand to the d(1) heme iron and switching to His/His coordination at the c-type heme. No reason for unusually weak binding of cyanide to the ferric state can be identified; rather it is argued that the protein is designed such that a chelate-based effect drives displacement by tyrosine of cyanide or a weaker ligand, like reaction product nitric oxide, from the ferric d(1) heme.

Crystallization and preliminary X-ray analysis of nitrous oxide reductase from Paracoccus pantotrophus.

Nitrous oxide reductase is a periplasmic respiratory protein with a novel copper catalytic centre; it catalyses the terminal step, reduction of nitrous oxide to nitrogen, of the bacterial denitrification process. Nitrous oxide reductase from Paracoccus pantotrophus has been crystallized by the hanging-drop method. A prerequisite for crystallization was the oxidation of the enzyme with potassium ferricyanide in order to obtain homogenous oxidation states of the copper centres. The crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 116.4, b = 118.3, c = 267.0 A. Two homodimers, of approximate molecular weight 67 kDa per subunit, probably constitute the asymmetric unit and give a Matthews coefficient, V(m), of 3.4 A(3) Da(-1) and a solvent content of 59% by volume. The crystals diffract X-rays to 3.0 A resolution on an in-house source and are suitable for structure determination.

Catalysis of serine oligopeptidases is controlled by a gating filter mechanism.

Proteases have a variety of strategies for selecting substrates in order to prevent uncontrolled protein degradation. A recent crystal structure determination of prolyl oligopeptidase has suggested a way for substrate selection involving an unclosed seven-bladed beta-propeller domain. We have engineered a disulfide bond between the first and seventh blades of the propeller, which resulted in the loss of enzymatic activity. These results provided direct evidence for a novel strategy of regulation in which oscillating propeller blades act as a gating filter during catalysis, letting small peptide substrates into the active site while excluding large proteins to prevent accidental proteolysis.

Beta propellers: structural rigidity and functional diversity.

Recently solved structures and proposed models have helped to reveal the structural characteristics of the beta-propeller fold, as well as the features that contribute to its high rigidity and stability. Possible strategies for identifying beta-propeller proteins in newly characterised sequences are helping to overcome the problems of predicting the beta-propeller fold from amino acid sequences.

Differential gene expression pattern between normal human trophoblast and choriocarcinoma cell lines: downregulation of heat shock protein-27 in choriocarcinoma in vitro and in vivo.

OBJECTIVE: Our purpose was to identify potential differences in gene expression between normal trophoblast and choriocarcinoma cells. METHODS: The Atlas human cDNA expression array hybridization technique was used to study the gene expression pattern in normal trophoblast and choriocarcinoma cell lines. Furthermore, to confirm heat shock protein-27 (Hsp-27) expression data, reverse transcriptase-PCR (RT-PCR), Western blot, and immunohistochemical analyses were used in vitro with cell lines and in vivo with paraffin sections. RESULTS: The expression of nine genes was strongly different comparing a normal trophoblast cell line with choriocarcinoma cells on the Atlas membranes. Compared to normal trophoblast cells, six genes were upregulated and three were downregulated in choriocarcinoma cells. Furthermore, the downregulation of Hsp-27 in choriocarcinoma cells was confirmed both in vitro with cell lines and in vivo with paraffin sections using RT-PCR, Western blot, and immunohistochemical techniques. CONCLUSION: cDNA expression array is a useful technique for identifying differentially expressed gene patterns in normal trophoblast and choriocarcinoma cells. The strong expression of Hsp-27 in placental villous trophoblast cells may play a role in trophoblast differentiation. The downregulation of Hsp-27 in choriocarcinoma may contribute to the extreme sensitivity of trophoblastic tumors to chemotherapy.

Matrix metalloproteinases and their inhibitors in gestational trophoblastic diseases and normal placenta.

OBJECTIVE: Our purpose was to investigate the expression of matrix metalloproteinases (MMPs) in gestational trophoblastic diseases and normal first-trimester placenta. METHODS: Paraffin sections of 16 partial moles, 25 complete moles, 10 gestational choriocarcinomas, and 11 normal first-trimester placentas were studied immunohistochemically for expression of MMP-1, MMP-2, MMP-3, MMP-9, MMP-13, and tissue inhibitor of metalloproteinase-1 (TIMP-1). RESULTS: Nine (90.0%) of the choriocarcinoma cases showed strong intensity of staining for MMP-1. Choriocarcinoma exhibited significantly stronger staining for MMP-1 than syncytiotrophoblast in normal placenta (P < 0.01), partial mole (P < 0.01), and complete mole (P < 0.01). Choriocarcinoma also showed significantly stronger staining for MMP-1 than the extravillous trophoblast in placenta (P < 0.05). MMP-2 was expressed only in syncytio- and extravillous trophoblasts in normal placenta, partial mole, and complete mole. Choriocarcinoma and the extravillous trophoblast in partial mole and complete mole had significantly stronger staining for MMP-2 than the extravillous trophoblast in placenta (P < 0.05, P < 0.01, P < 0.01, respectively). Choriocarcinoma also exhibited significantly stronger staining for MMP-2 than syncytiotrophoblasts in placenta (P < 0.01), partial mole (P = 0.05), and complete mole (P < 0.01). The expression of MMP-3, MMP-9, and MMP-13 was similar in all four tissues with the predominance of syncytiotrophoblast for MMP-3 and MMP-13 and cytotrophoblast for MMP-9. While 8 (73.0%) placentas, 14 (87.5%) partial moles, and 19 (76.0%) complete moles showed strong immunoreactivity for TIMP-1 in syncytiotrophoblasts, no strong staining was found in choriocarcinomas (P < 0.01, P < 0.01, P < 0.01, respectively). CONCLUSION: The extravillous trophoblast of first-trimester placenta has significantly less expression of MMP-1 than choriocarcinoma and significantly less expression of MMP-2 than choriocarcinoma and extravillous trophoblast of partial and complete mole. The expression of TIMP-1 was significantly less in choriocarcinoma than the syncytiotrophoblast of normal placenta, partial mole, and complete mole. MMPs and their inhibitors may play a role in the pathogenesis of gestational trophoblastic diseases.

Prolyl oligopeptidase: an unusual beta-propeller domain regulates proteolysis.

Prolyl oligopeptidase is a large cytosolic enzyme that belongs to a new class of serine peptidases. The enzyme is involved in the maturation and degradation of peptide hormones and neuropeptides, which relate to the induction of amnesia. The 1.4 A resolution crystal structure is presented here. The enzyme contains a peptidase domain with an alpha/beta hydrolase fold, and its catalytic triad (Ser554, His680, Asp641) is covered by the central tunnel of an unusual beta propeller. This domain makes prolyl oligopeptidase an oligopeptidase by excluding large structured peptides from the active site. In this way, the propeller protects larger peptides and proteins from proteolysis in the cytosol. The structure is also obtained with a transition state inhibitor, which may facilitate drug design to treat memory disorders.

DOC-2/hDab2, a candidate tumor suppressor gene involved in the development of gestational trophoblastic diseases.

Gestational trophoblastic diseases comprise a spectrum of interrelated diseases including partial mole, complete mole and gestational choriocarcinoma. Using reverse transcriptase PCR (RT-PCR) analysis, we identified higher levels of DOC-2/hDab2 expression in the normal trophoblast cells in culture than in choriocarcinoma cell lines. Subsequent study using immunohistochemistry showed high levels of DOC-2/hDab2 protein expression in normal trophoblast tissues but significantly lower levels of expression in gestational trophoblastic disease tissues, particularly in complete mole and choriocarcinoma. When DOC-2/hDab2 was transfected into the choriocarcinoma cell lines, Jar, JEG and BeWo, the stable transfectants showed significantly reduced growth rate in culture. These data suggest that down regulation of DOC-2/hDab2 may play an important role in the development of gestational trophoblastic diseases.

c-myc, c-erbB-2, c-fms and bcl-2 oncoproteins. Expression in normal placenta, partial and complete mole, and choriocarcinoma.

OBJECTIVE: To determine the expression of bcl-2, c-myc, c-fms and c-erbB-2 oncoproteins in normal placentas, partial and complete hydatidiform moles, and choriocarcinomas and to examine the possible presence of mutations in the K-ras gene in complete moles and choriocarcinomas. STUDY DESIGN: The expression of the above oncoproteins was determined immunohistochemically by specific antibodies for these proteins on formalin-fixed paraffin sections of 18 normal placentas, 17 partial moles, 25 complete moles and 11 choriocarcinomas. This was followed by polymerase chain reaction analysis (exons 12 and 13) of K-ras gene for possible mutations in complete moles and choriocarcinomas. RESULTS: Expression of c-fms oncoprotein appeared confined to the cytoplasm of syncytiotrophoblastic cells. The c-fms protein staining intensity of the syncytiotrophoblastic layer showed no significant difference among the four gestational tissues. c-erbB-2 antibody expression was confined to the cellular membrane of the extravillous trophoblast. When compared with normal placenta or partial mole, the expression of c-erbB-2 protein was significantly stronger in complete mole (P < .0001 and P < .0001, respectively) and choriocarcinoma (P < .0001 and P < .0001, respectively). Expression of bcl-2 protein was significantly stronger in the syncytiotrophoblast in complete mole and choriocarcinoma as compared to both normal placenta and partial mole (P < .0001 and P < .0001, respectively). Staining of c-myc of the syncytiotrophoblastic layer was significantly stronger in placenta, complete mole and choriocarcinoma than in partial mole (P < .0001, P < .0001 and P < .0001, respectively). Mutation in K-ras gene was not found in any of the 22 complete moles or 11 choriocarcinomas examined. CONCLUSION: Our data suggest that c-myc, c-erbB-2, c-fms and bcl-2 oncoproteins may be important in the pathogenesis of complete mole and choriocarcinoma. However, while both complete mole and choriocarcinoma were characterized by overexpression of c-myc, c-erbB-2 and bcl-2, partial mole generally did not strongly express these three oncoproteins.

p53, p21, Rb and mdm2 oncoproteins. Expression in normal placenta, partial and complete mole, and choriocarcinoma.

OBJECTIVE: To determine the expression of p53, p21, Rb and mdm2 proteins in normal placentas, partial and complete hydatidiform moles, and choriocarcinomas and to examine possible p53 mutations in specimens from p53-positive cases. STUDY DESIGN: Expression of the above oncoproteins was determined immunohistochemically by specific antibodies for these proteins on formalin-fixed paraffin sections of 18 normal placentas, 17 partial moles, 25 complete moles and 11 choriocarcinomas. This was followed by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis (exons 5, 6, 7, 8, 9, 10, 11) for possible p53 mutation in specimens from p53-positive cases of complete mole and choriocarcinoma. RESULTS: p53 Oncoprotein immunoreactivity was significantly stronger in complete mole and choriocarcinoma than in normal placenta (P < .0001, P < .0001) and in partial mole (P < .0001, P < .0001). Positive staining for p21 oncoprotein was also significantly stronger in complete mole (P < .0001, P < .0001) and in choriocarcinoma (P < .0001, P < .0001) than in placenta and partial mole. We found significantly stronger staining for Rb protein in complete mole (P < .03) and choriocarcinoma (P < .03) than in partial mole. Partial mole and complete mole expressed significantly stronger staining of mdm2 than placenta (P < .007, P < .07, respectively). We found only one nonsense mutation in p53 with PCR analysis; that strongly suggests that in complete mole and choriocarcinoma the overexpressed p53 protein was wild type. CONCLUSION: Altered expression of p53, p21, Rb and mdm2 may be important in the pathogenesis of both complete mole and choriocarcinoma. However, unlike complete molar pregnancy, partial mole is not characterized by overexpression of p53. Overexpression of p53 and mdm2 proteins in complete mole and choriocarcinoma may be associated with more aggressive behavior in gestational trophoblastic disease.