Chromatin dynamics at the hTERT promoter during transcriptional activation and repression by c-Myc and Mnt in Xenopus leavis oocytes

The transcription factors c-Myc and Mnt regulate gene expression through dimerization with Max and binding to E-boxes in target genes. While c-Myc activates gene expression via recruitment of histone modifying complexes, Mnt acts as a transcriptional repressor. Here, we used the Xenopus leavis oocyte system to address the effect of c-Myc and Mnt on transcription and chromatin remodeling over the E-box region in the human telomerase reverse transcriptase (hTERT) promoter. As expected we found elevated and decreased levels of hTERT transcription upon exogenously expressed c-Myc/Max and Mnt/Max, respectively. In addition, we confirmed binding of these heterodimers to both E-boxes already enriched with H3K9ac and H4K16ac. These chromatin marks were further enhanced upon c-Myc/Max binding followed by increased DNA accessibility in the E-box region. In contrast, Mnt/Max inhibited Myc-induced transcription and mediated repression through complete chromatin condensation and deacetylation of H3K9 and H4K16 across the E-box region. Importantly, Mnt was able to counteract c-Myc mediated activation even when expressed at low levels, suggesting Mnt to act as a strong repressor by closing the chromatin structure. Collectively our data demonstrate that the balance between c-Myc and Mnt activity determines the transcriptional outcome of the hTERT promoter by modulation of the chromatin architecture.

Mnt takes control as key regulator of the myc/max/mxd network

Myc is the most frequently deregulated oncogene in human tumors. The protein belongs to the Myc/Max/Mxd network of transcriptional regulators important for cell growth, proliferation, differentiation, and apoptosis. The ratio between Mnt/Max and c-Myc/Max on the 5'-CACGTG-3' E-box sequence at shared target genes is of great importance for cell cycle progression and arrest. Serum stimulation of quiescent cells results in phosphorylation of Mnt and disruption of the critical Mnt-mSin3-HDAC1 interaction. This in turn leads to increased expression of the Myc/Mnt target gene cyclin D2. It is therefore possible that Myc function relies on its ability to overcome transcriptional repression by Mnt and that relief of Mnt-mediated transcriptional repression is of greater importance for regulation of target genes than the sole activation by Myc. In addition, Mnt has many features of a tumor suppressor and may thus be nonfunctional or inactivated in human tumors. In summary, accumulating evidence supports the model of Mnt as the key regulator of the network in vivo.

Identification of recognition sites for myc/max/mxd network proteins by a whole human chromosome 19 selection strategy

In this study, we have identified 20 human sequences containing Myc network binding sites in a library from the whole human chromosome 19. We demonstrated binding of the Max protein to these sequences both in vitro and in vivo. The majority of the identified sequences contained one or several CACGTG or CATGTG E-boxes. Several of these sites were located within introns or in their vicinity and the corresponding genes were found to be up- or down-regulated in differentiating HL-60 cells. Our data show the proof of principle for using this strategy in identification of Max target genes, and this method can also be applied for other transcription factors.

Mnt transcriptional repressor is functionally regulated during cell cycle progression

The Myc/Max/Mad network of transcription factors regulates cell proliferation, differentiation, and transformation. Similar to other proteins of the network, Mnt forms heterodimers with Max and binds CACGTG E-Box elements. Transcriptional repression by Mnt is mediated through association with mSin3, and deletion of the mSin3-interacting domain (SID) converts Mnt to a transcriptional activator. Mnt is coexpressed with Myc in proliferating cells and has been suggested to be a modulator of Myc function. We report that Mnt is expressed both in growth-arrested and proliferating mouse fibroblasts and is phosphorylated when resting cells are induced to re-enter the cell cycle. Importantly, the interaction between Mnt and mSin3 is disrupted upon serum stimulation resulting in decreased Mnt-associated HDAC activity. Furthermore, we demonstrate that Mnt binds and recruits mSin3 to the Myc target gene cyclin D2 in quiescent mouse fibroblasts. Interference with Mnt expression by RNAi resulted in upregulation of cyclin D2 expression in growth-arrested fibroblasts, supporting the view that Mnt represses cyclin D2 transcription in quiescent cells. Our data suggest a model in which phosphorylation of Mnt at cell cycle entry results in disruption of Mnt-mSin3-HDAC1 interaction, which allows induction of Myc target genes by release of Mnt-mediated transcriptional repression.

Estrogen receptors and proliferation markers in primary and recurrent breast cancer

To elucidate the clinical importance of estrogen receptor (ER) beta in breast cancer, 29 archival primary breast cancer specimens, six locally recurrent cancers, and five benign mammary tumors were examined histochemically for ERalpha, ERbeta and the proliferation markers Ki67 and cyclin A. In benign tumors, most epithelial cells contained ERbeta, but ERalpha was rare. In primary cancers, both ERalpha and ERbeta occurred in epithelial cells, the presence of ERbeta being associated with elevated expression of Ki67 and cyclin A, and ERalpha with decreased levels. Thus, the highest content of proliferation markers was seen in primary cancers that were ERalpha(-) ERbeta(+). Most Ki67-containing cells coexpressed ERbeta, but few showed ERalpha. In locally recurring cancers, ERalpha, ERbeta, and Ki67 were more highly expressed than in the corresponding primary tumors, and many cells containing ERbeta, but few with ERalpha, expressed Ki67. Surprisingly, ERbeta, but not ERalpha, was seen in the stromal cells of both primary and recurrent cancers. Because the response of breast cancers to tamoxifen therapy is correlated with the presence of ERalpha, cancer cells that lack ERalpha but contain ERbeta and proliferation markers represent a novel population of apparently proliferating cells that probably are not targeted by the current antiestrogens. Thus, appropriate ERbeta-specific ligands, perhaps in combination with tamoxifen, may be useful in improving the treatment of breast cancers.

A 5-year follow-up study on the use of a levonorgestrel intrauterine system in women receiving hormone replacement therapy

OBJECTIVE

To investigate endometrial histology, bleeding, and the effects of replacing the levonorgestrel intrauterine system (LNG IUS, Mirena/Levonova, Leiras Oy, Turku, Finland) after 5 years of combined use with estrogen.

DESIGN

Prospective cohort study.

SETTING

Private outpatient clinic.

PATIENT(S)

Forty postmenopausal women started hormone replacement therapy with LNG IUS and either a patch (50 microg/24 h) or oral (2 mg) estradiol valerate protocol. Thirty-nine completed 12 months of treatment. Twenty-nine of them had used LNG IUS with continuous estradiol replacement therapy for 5 years. Seven of them volunteered to a 3-month treatment-free period before reinsertion; 22 opted for immediate reinsertion.

INTERVENTION(S)

Endometrial sampling for histology, endometrial thickness, and location of the LNG IUS by ultrasound at removal and after washout. The women completed bleeding diaries from 3 months prior to removal to 3 months after reinsertion.

MAIN OUTCOME MEASURE(S)

Endometrial histology was evaluated and estrogen and progestin effects were also investigated. Endometrial thickness was measured. Bleeding was examined based on bleeding diaries. The investigator and the women evaluated the insertion, removal, and reinsertion of the LNG IUS.

RESULT(S)

At 6 and 12 months endometrial histology was nonproliferative. At removal, all endometria were suppressed and a strong progestin effect was seen. The thickest endometrium was 3.6 mm. After washout, all seven endometria were atrophic. Before the IUS was replaced, 26 women were amenorrheic, whereas three had minor spotting. After replacement 5 women had no bleeding and an additional 10 women had only spotting. The bleeding or spotting discontinued within 18 days. The insertion of LNG IUS was characterized as easy by the investigator and it was well tolerated by the women. Cervical dilatation and/or paracervical blockade was used in 10 insertions.

CONCLUSION(S)

Intrauterine levonorgestrel effectively protects against endometrial hyperplasia. In most women it induces amenorrhea, which is only temporarily affected by replacement of the LNG IUS.

The levels of trypsinogen isoenzymes in ovarian tumour cyst fluids are associated with promatrix metalloproteinase-9 but not promatrix metalloproteinase-2 activation

Proteolysis mediated by matrix metalloproteinases (MMPs) and serine proteinases is associated with cancer invasion and metastasis. Activation of latent proMMPs, and especially the proforms of the type IV collagen degrading gelatinases A and B (proMMP-2 and proMMP-9), is thought to be a critical step in this process. We have recently found that human tumour-associated trypsin-2 is a potent activator of proMMP-9 and it also activates proMMP-2 in vitro. Trypsinogen, MMP-2, and MMP-9 are expressed in ovarian cancer. To elucidate the function of trypsin in vivo, we studied whether high concentrations of trypsinogen-1, trypsinogen-2, their alpha(1)-proteinase inhibitor (API) complexes, and tumour-associated trypsin inhibitor (TATI) are associated with proMMP-2 and proMMP-9 activation in ovarian tumour cyst fluids. Zymography and immunofluorometric analysis of 61 cyst fluids showed a significant association between high trypsin concentrations and the activation of MMP-9 (P = 0.003-0.05). In contrast, the trypsin concentrations were inversely associated with the activation of MMP-2 (P = 0.01-0.02). Immunohistochemical analysis of ovarian tumour tissue demonstrated expression of trypsinogen-2 and TATI in the secretory epithelium. MMP-2 was detected both in stromal and epithelial cells whereas MMP-9 was detected in neutrophils and macrophage-like cells in stromal and epithelial areas. These results suggest that trypsin may play a role in the regulation of the MMP-dependent proteolysis associated with invasion and metastasis of ovarian cancer.

Prospective study on gynaecological effects of two antioestrogens tamoxifen and toremifene in postmenopausal women

To assess and compare the gynaecological consequences of the use of 2 antioestrogens we examined 167 postmenopausal breast cancer patients before and during the use of either tamoxifen (20 mg/day, n = 84) or toremifene (40 mg/day, n = 83) as an adjuvant treatment of stage II-III breast cancer. Detailed interview concerning menopausal symptoms, pelvic examination including transvaginal sonography (TVS) and collection of endometrial sample were performed at baseline and at 6, 12, 24 and 36 months of treatment. In a subgroup of 30 women (15 using tamoxifen and 15 toremifene) pulsatility index (PI) in an uterine artery was measured before and at 6 and 12 months of treatment. The mean (+/-SD) follow-up time was 2.3 +/- 0.8 years. 35% of the patients complained of vasomotor symptoms before the start of the trial. This rate increased to 60.0% during the first year of the trial, being similar among patients using tamoxifen (57.1%) and toremifene (62.7%). Vaginal dryness, which was present in 6.0% at baseline, increased during the use of tamoxifen (26.2%) and toremifene (24.1%). Endometrial thickness increased from baseline (3.9 +/- 2.7 mm) to 6.8 +/- 4.2 mm at 6 months (P< 0.001), and no difference emerged between the 2 regimens in this regard. Before the start of the antioestrogen regimen, the endometrium was atrophic in 71 (75.5%) and proliferative in 19 of 94 (20.2%) samples; 4 patients had benign endometrial polyps. During the use of antioestrogen altogether 339 endometrial samples were taken (159 in tamoxifen group, 180 in toremifene group). The endometrium was proliferative more often in the tamoxifen group (47.8%) than in the toremifene group (32.2%) (P< 0.0001). 20 patients had a total of 24 polyps (17 in tamoxifen and 9 in toremifene group, P< 0.05) during the use of antioestrogens. One patient in the toremifene group developed endometrial adenocarcinoma at 12 months, and one patient had breast cancer metastasis on the endometrium. Tamoxifen failed to affect the PI in the uterine artery, but toremifene reduced it by 15.0% (P< 0.05) by 12 months. In conclusion, tamoxifen and toremifene cause similarly vasomotor and vaginal symptoms. Neither regimen led to the development of premalignant endometrial changes. Our data suggest that so close endometrial surveillance as used in our study may not be mandatory during the first 3 years of use of antioestrogen treatment.

Effect of an estradiol gel with monthly or quarterly progestogen on menopausal symptoms and bleeding

OBJECTIVE

To assess the acceptability, efficacy and endometrial safety of transdermal estradiol gel (Divigel/Sandrena) combined with monthly or quarterly oral progestogen (medroxyprogesterone acetate).

METHODS

This 12-month, multicenter, open-label study was carried out at 12 study centers in Finland and Sweden. A total of 395 postmenopausal women received 1 mg estradiol in 1 g gel, daily, with oral medroxyprogesterone acetate 10 mg for the first 12 days every month (groups I and III) or every 3 months (group II). The main outcome measures were relief of climacteric symptoms, bleeding patterns and endometrial safety.

RESULTS

All regimens reduced the severity of hot flushes, sweating episodes and vaginal dryness. In groups I and III, approximately 80% and 70% of women, respectively, had regular monthly withdrawal bleeding (excepting the first cycle), with irregular bleeding in 8.3% and 5.3% of treatment months. In group II, approximately 94% of women had regular tri-monthly withdrawal bleeding, with irregular bleeding in 10.7% of the treatment months. Endometrial hyperplasia was observed in 0.3% of women. More than 87% of subjects completed the study, and 97% of these rated the gel as acceptable or convenient.

CONCLUSIONS

Both the 1- and 3-month regimens were equally effective in controlling climacteric symptoms and protecting against endometrial hyperstimulation. The bleeding patterns were comparable between groups and were similar to those reported for oral estrogens. Estradiol gel was highly acceptable to the majority of women.

Chlamydia trachomatis seropositivity is associated both with stillbirth and preterm delivery

The cause of stillbirth and preterm delivery is often unknown. We studied the prevalence of Chlamydia trachomatis antibodies in mothers with stillbirth and preterm labor. Serum specimens from 72 mothers with stillbirth after the 21st gestational week, and from 48 mothers with preterm delivery between gestational weeks 23 and 29, both from the greater Helsinki area, and cord blood from 96 consecutive liveborn deliveries at the Department of Obstetrics and Gynecology, the University of Helsinki, were studied for antibodies to C. trachomatis immunotypes CJHI, GFK and BED by microimmunofluorescence test. The prevalence of C. trachomatis antibodies was highest, 33.3%, in mothers with stillbirth, 18.8% in mothers with preterm delivery, and 10.4% in cord blood. The IgM seropositivity rate was high among mothers with preterm delivery (8.3%). We conclude that C. trachomatis IgG antibodies are frequently detected in sera from mothers with stillbirth, suggesting past infection, while mothers with preterm delivery often have serum IgM antibodies, suggesting of acute infection.

Reproductive features in women developing ovarian granulosa cell tumour at a fertile age

Ovarian granulosa cell tumour (GCT) is a rare malignancy, which has been linked to both infertility and infertility treatment with ovulation inducers. The reproductive features were analysed of 146 women with GCT diagnosed between 1956 and 1996. During the study period no changes were found in the mean age (53 years), menopausal status (59% postmenopausal), parity (32% nulliparous) or tumour size or stage at diagnosis. The clinical features in women with GCT at fertile age were compared with GCT diagnosed later in life and to population-based data. Nulliparity (50%) and history of infertility (22%) were more frequent if the tumour occurred at fertile age (n = 50). Of the 12 infertile cases, seven had anovulatory infertility (58%); 11 occurred during the era of ovulation inducers, but only five had used these drugs (clomiphene citrate in five patients, gonadotrophins in two, and tamoxifen in one patient) and no patient had undergone in-vitro fertilization. Endometrial hyperplasia was associated with GCT at all ages, while endometrial cancer was found solely after the age of 45 years. In conclusion, GCT at fertile age is associated with nulliparity and with a clinical presentation of anovulatory infertility, while GCT later in life is associated with a more normal average fertility pattern and with occurrence of endometrial cancer.

A novel method to culture laryngeal human papillomavirus-positive epithelial cells produces papilloma-type cytology on collagen rafts

A novel method to culture human papillomavirus (HPV) positive laryngeal epithelial cells is described. Biopsies of laryngeal papillomas and of HPV-positive laryngeal mucosa were first cultured as a monolayer in which irradiated laryngeal fibroblasts originally derived from a papilloma (PPLF-XR) patient served as feeder cells. When these fourth or fifth passage epithelial cells were transferred to allow growth on an organotypic growth base (collagen raft containing unirradiated PPLF), they grew as a multilayer. This layer showed features typical of HPV infection with koilocytosis, parakeratosis, and isolated dyskeratotic cells. Based on in situ hybridisation, the original tumour sections and epithelial cells from each monolayer passage, as well as the collagen raft sections, contained HPV DNA. Our results show that HPV-infected epithelial cells can be maintained during passages in monolayer culture and that PPLF can support the growth of these cells well. The monolayer cell culture and the collagen raft, the latter providing differentiation-promoting effects, appears to facilitate maintenance of the infected cells and of the viral genome.

Controlled release gel of ibuprofen and lidocaine in epidural use--analgesia and systemic absorption in pigs

PURPOSE

Reduction of the frequency of injections and localization of the absorption of drug molecules to the injection site would be of great advantage in epidural pain treatment. The epidural use of a controlled release gel of lidocaine and ibuprofen was studied.

METHODS

The effect of a poloxamer gel (25%) containing 2% lidocaine.HCl and 2% ibuprofen.Na on the duration of analgesia after epidural administration to pigs was compared with drug in solution. Analgesia was assessed by observing the motor function and the nociceptive reflex-withdrawal response to painful pressure stimulation on the feet. Pharmacokinetic and histological examinations were performed.

RESULTS

Analgesia lasted significantly longer after epidural lidocaine gel injection in comparison with the solution. The gel prolonged the systemic absorption, thereby increasing the epidural availability of lidocaine for spinal analgesia. Although the absorption of ibuprofen was prolonged after epidural gel injection, the duration of analgesia as compared with the solution was not prolonged. After epidural injection, only slight inflammatory changes were observed in the tissue structures of the epidural space, but none in the spinal cord.

CONCLUSIONS

These results demonstrate poloxamer gel to be a promising controlled-release, injectable epidural formulation for the management of pain.

Distinct chromosomal imbalances in uterine serous and endometrioid carcinomas

Endometrial carcinoma shows various histological types that differ in their clinical presentation and prognosis. Comparative genomic hybridization was used to detect gains and losses of DNA sequences along all chromosome arms in 24 uterine serous and 24 uterine endometrioid carcinomas. In serous carcinomas, extensive genetic aberrations were detected in 17 of the 24 specimens, with a mean of 5.7 changes per tumor. The most frequent gains occurred at 3q (50%), 8q (33%), 5p (29%), 6p (29%), and 1q (29%), and the most common losses were located at 4q (17%), 15q (17%), and 18q (17%). Tumors exhibiting DNA copy number changes were associated with shorter overall survival. In endometrioid carcinomas, genetic aberrations were less frequent and simpler than in serous carcinomas. DNA sequence copy number changes were observed in 12 of the 24 cases, with a mean of 1.5 changes per tumor. The most frequent aberrations were gains at 1q (29%), 2q (13%), and 8q (13%). Losses were rarely observed. The diverging pattern of genetic changes observed in uterine serous and endometrioid carcinomas suggests different pathways of carcinogenesis in these tumor types.

Effects of transdermal oestrogen therapy in postmenopausal women: a comparative study of an oestradiol gel and an oestradiol delivering patch

OBJECTIVE

To compare the efficacy, safety and tolerability of an oestradiol gel (1.0 mg of oestradiol daily, Divigel/Sandrena) with those of an oestradiol delivering patch (delivering 50 micrograms oestradiol/24 h, Estraderm TTS) in hormone replacement therapy of postmenopausal women. Dydrogesterone tablets (Terolut), 10 mg daily for the first 12 days of every month, were used as the progestogen component of the therapy.

MAIN OUTCOME MEASURES

The effect of treatment on clinical symptoms and on endometrium, total body bone mineral density and lipid metabolism as well as the tolerability of the treatments with special emphasis on skin irritation and compliance were evaluated.

DESIGN

An open, randomised, controlled, parallel-group trial of 12 months' duration.

SETTING

The Medical Clinic of Kalevankatu, Helsinki, Finland.

PARTICIPANTS

One hundred twenty postmenopausal women were treated with transdermal oestradiol combined with dydrogesterone. In addition, 25 women without HRT served as a reference group for the bone mineral density measurements.

RESULTS

Both treatment regimens were equally effective in alleviating climacteric symptoms, preserving bone mineral density and were equally safe. A trend towards heavier bleeding was detected in patients treated with the oestradiol delivering patch. A statistically nonsignificant decrease of total cholesterol and triglyceride concentrations but no change in high-density lipoprotein cholesterol concentration was observed in both groups. The acceptability of the treatment was higher in the gel group (96.4%) than in the patch group (90.7%). Only two (3.3%) women using the oestradiol gel complained of skin irritation whereas 28 patients (46.7%, P < 0.001) using the oestradiol delivering patch reported this adverse effect.

CONCLUSIONS

Both the oestradiol gel and the oestradiol delivering patch are equally effective in hormone replacement therapy but the gel preparation is less irritative to the skin.

Chlamydia trachomatis detected in human placenta

AIMS

To evaluate the relation between Chlamydia trachomatis infection and stillbirth, placental tissue was studied for the presence of C trachomatis.

METHODS

Paraffin wax embedded placental tissue of a stillbirth fetus, born at the 36th week of gestation to a 21 year old mother with high serum antibody titres to C trachomatis immunotypes during pregnancy and who was culture positive to C trachomatis three years previously, was studied by in situ hybridisation, polymerase chain reaction, and immunohistochemistry for the presence of C trachomatis.

RESULTS

C trachomatis was detected in placental specimens by in situ hybridisation and alkaline phosphatase antialkaline phosphatase staining in several sections, whereas control tissues were uniformly negative, indicating the presence of C trachomatis nucleic acid and antigen in the placenta.

CONCLUSION

This is the first reported case in which C trachomatis has been demonstrated in the human placenta.

Malignant tumors of the ovary or the breast in association with infertility: a report of thirteen cases

BACKGROUND

Many questions have been raised recently about the relationship between infertility, fertility drugs and cancer. This prompted us to evaluate our patients having ovarian or breast cancer with a known history of infertility.

METHODS

We report thirteen women who had been examined and/or treated for infertility before the occurrence of malignant tumors of the ovary or the breast at an age under 50 years in 1990-1995 in our unit.

RESULTS

Mean age of the patients was 35 years (s.d. 5.9 years, range 28-47 years). Of the 11 ovarian tumors, one was a malignant teratoma, two were granulosa cell tumors and eight epithelial ovarian cancers. Ten women had received either clomiphene citrate alone or together with gonadotrophins, one had used only gonadotrophins, and in two patients ovarian cancer was detected during an infertility work-up but before any treatment. Four women had used clomiphene for more than twelve cycles. Two patients had ductal breast cancer.

CONCLUSIONS

Our patients emphasize the need for follow-up and long-term prospective studies in infertile women who have been evaluated or treated for infertility.

Complement-regulatory proteins in ovarian malignancies

Ovarian cancer has features that makes it well-suited for MAb adjuvant immunotherapy. Several of the MAbs used in clinical trials mediate cancer cell destruction by activation of complement (C). In this study, therefore, we examined the ability of ovarian-tumor cells to resist C attack. We found that the C regulators membrane cofactor protein (MCP, CD46) and protectin (CD59) were strongly expressed in the tumor cells in all 28 benign and malignant tumors examined. Decay-accelerating factor (DAF; CD55) was more heterogeneously expressed, and only 75% of the tumors exhibited a moderate amount of DAF in the tumor cells. In adenoma cells, CD59 and DAF were preferentially located apically, while in adenocarcinoma cells they were expressed also at the basolateral cell surface. The ovarian-carcinoma cell lines SK-OV-3, Caov-3, SW626 and PA-1 expressed both the 58- and the 68-kDa isoforms of MCP. DAF was present as a glycosyl-phosphatidylinositol(GPI)-anchored 70-kDa glycoprotein. The surface-expression level of DAF varied, and correlated with the vulnerability of the cells to C-mediated lysis. CD59 was expressed as a GPI-linked 19- to 25-kDa protein exhibiting multiple glycosylation variants. The surface expression of CD59 correlated with the amount of the main 1.9 + 2.1-kb CD59 mRNA transcripts. Neutralization of CD59 with an anti-CD59 MAb significantly enhanced C-mediated killing of the cell lines. Low expression of C regulators on the PA-1 teratocarcinoma cell line was associated with high sensitivity to C lysis. Thus, the expression of C regulators on malignant ovarian cells may constitute a tumor escape mechanism, and is a critical parameter to be examined when MAb therapy is being considered.

Evidence for divergence of DNA copy number changes in serous, mucinous and endometrioid ovarian carcinomas

Comparative genomic hybridization was applied to detect and map changes in DNA copy number in 24 well or moderately differentiated epithelial ovarian carcinomas (eight serous, eight mucinous and eight endometrioid carcinomas). Twenty-three of the 24 tumours showed changes in DNA copy number in one or several regions (median 4, range 1-17). Gains were more frequent than losses (ratio 1.6:1.0). The most frequent gains occurred in chromosomes 1q (38%), 2p (29%), 7q (25%), 8q(38%) and 17q (38%), and the most common losses were located in chromosomes 8p (21%), 9p (25%) and 13q (21%). High-level amplifications were detected in seven tumours at 1q22-32, 2p15-22, 3qcen-23, 6p21-22 and 8q. In the three histological subtypes the copy number karyotypes showed substantial differences. Gains at 1q were observed in endometrioid (five cases) and serous tumours (four cases). Increased copy number at 10q was seen in endometrioid tumours only (four cases), whereas gains at 11q occurred mostly in serous tumours (four cases). In mucinous tumours, the most common copy number change was a gain at 17q (six cases). The results show that, in epithelial ovarian carcinoma, changes in DNA copy number are a rule rather than an exception, chromosomes 1, 2, 7, 8, 9, 13 and 17 being the most frequently affected. The diverging pattern of genetic changes seen in epithelial ovarian carcinomas with different histological phenotypes suggests that various pathways may lead to tumorigenesis and/or progression in these subgroups.

Ezrin expression in stromal cells of capillary hemangioblastoma. An immunohistochemical survey of brain tumors

Ezrin is a cytoskeleton-associated protein that appears to link actin filaments to the plasma membrane. Immunocytochemical studies suggest that ezrin is expressed in epithelial cells but not in mesenchymal cells. In addition, ezrin is expressed by certain epithelial tumors, such as renal cell adenocarcinomas. Ezrin serves as a tyrosine kinase substrate, and is phosphorylated in epidermal growth factor-stimulated cells. Ezrin may thus mediate regulatory signals in different cell functions. We studied the distribution of ezrin in 104 cases of primary tumors of the central nervous system (CNS) by immunocytochemistry. Special interest was focused on capillary hemangioblastoma, owing to its resemblance to renal cell adenocarcinoma, and on malignant gliomas, owing to their frequent epidermal growth factor receptor amplification. The stromal cells of hemangioblastomas were found to be strongly positive for ezrin. No expression was detected in gliomas and, except for hemangioblastomas, ezrin expression was restricted to those few CNS tumors that show epithelial differentiation, ie, choroid plexus papillomas, craniopharyngiomas, ependymomas, and cysts. The diffuse cytoplasmic expression of ezrin in the stromal cells of capillary hemangioblastoma may indicate that stromal cells overexpress ezrin or express ezrin with deficient binding properties.

Controlled release of lidocaine from injectable gels and efficacy in rat sciatic nerve block

PURPOSE

Methods of delaying the action of local anesthetics are important, since short duration of action limits their use in the treatment of postoperative and chronic pain. The present study evaluated the use of low-viscosity gels in prolonging the release of lidocaine.

METHODS

Release of lidocaine from 2% lidocaine.HCl containing methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), sodiumcarboxymethyl cellulose (CMC), and poloxamer 407 (PO) gels was studied in phosphate buffer, pH 7.4, at 37 degrees C. Commercial metylcellulose gel (MCcom) served as control. The in vivo efficacy of the respective gel formulations were evaluated in rats. The gel was injected into the vicinity of the sciatic nerve and nociception and motor function were tested.

RESULTS

The cumulative amount of lidocaine released during 8 hr was slowest from the PO gel, followed by the CMC, HPMC and MC gels. The antinociceptive effect was not prevented by the motor block and lasted longest with the PO gel. Good linear and rank order correlation was obtained between in vitro and in vivo results. The microscopic examination of the tissue samples revealed only mild or no irritation of the skeletal muscle tissue by the PO, HPMC, and CMC gels.

CONCLUSIONS

Based on these results poloxamer gel proved to be the most promising carrier for lidocaine.

Ezrin has a COOH-terminal actin-binding site that is conserved in the ezrin protein family

Ezrin, previously also known as cytovillin, p81, and 80K, is a cytoplasmic protein enriched in microvilli and other cell surface structures. Ezrin is postulated to have a membrane-cytoskeleton linker role. Recent findings have also revealed that the NH2-terminal domain of ezrin is associated with the plasma membrane and the COOH-terminal domain with the cytoskeleton (Algrain, M., O. Turunen, A. Vaheri, D. Louvard, and M. Arpin. 1993. J. Cell Biol. 120: 129-139). Using bacterially expressed fragments of ezrin we now demonstrate that ezrin has an actin-binding capability. We used glutathione-S-transferase fusion proteins of truncated ezrin in affinity chromatography to bind actin from the cell extract or purified rabbit muscle actin. We detected a binding site for filamentous actin that was localized to the COOH-terminal 34 amino acids of ezrin. No binding of monomeric actin was detected in the assay. The region corresponding to the COOH-terminal actin-binding site in ezrin is highly conserved in moesin, actin-capping protein radixin and EM10 protein of E. multilocularis, but not in merlin/schwannomin. Consequently, this site is a potential actin-binding site also in the other members of the protein family. Furthermore, the actin-binding site in ezrin shows sequence homology to the actin-binding site in the COOH terminus of the beta subunit of the actin-capping protein CapZ and one of the potential actin-binding sites in myosin heavy chain. The actin-binding capability of ezrin supports its proposed role as a membrane-cytoskeleton linker.

Altered growth behavior of human cervical epithelial cells transfected by HPV type 16 and 18 DNA

Transfection of primary human cervical epithelial (HCE) cells with full-length HPV type 16 and 18 DNAs resulted in cell lines that could grow continuously. Four HPV DNA-immortalized cell lines were established. Morphologically the immortalized cells resembled primary HCE cells. Electron microscopy showed that they contained desmosomes and keratin filaments, which are characteristic structural components of epithelial cells. Each cell line had a unique integration pattern of HPV DNA but the transcription patterns were similar in the 3 HPV 16 DNA-immortalized cell lines. The expression patterns of viral DNA in the HPV 18 DNA-immortalized cell line were similar to that in HeLa cells, suggesting transcription of mainly early viral genes. The cell lines, unlike HeLa and SiHa carcinoma cells, did not form tumors in nude mice or grow in soft agarose, but collagen raft culture indicated that the immortalized cell lines had lost the capacity of normal differentiation compared with primary HCE cells. Morphologically, the aberrant differentiation of the immortalized cells showed great resemblance to cervical intra-epithelial neoplasia. The altered pattern of growth and differentiation of human cervical epithelial cells transfected by HPV 16 and 18 DNAs is in agreement with the view that HPV types 16 and 18 play an important role at an initial step of human cervical epithelial carcinogenesis but that co-carcinogenic factors are necessary for full malignant transformation in vivo.

Correlation of beta-camera imaging and immunohistochemistry in radioimmunotherapy using 90Y-labeled monoclonal antibodies in ovarian cancer animal models

Tumor stroma contains much fibrin and monoclonal antifibrin antibody targeting is possible in tumors. In this study, nude mouse human ovarian carcinoma xenograft specimens were investigated after treatment with 90Y-labeled monoclonal antifibrin antibody Fab fragment or with 90Y-labeled OC125-monoclonal antibody F(ab')2 fragments. The mice received the radioimmunotherapy activity either intratumorally, intraperitoneally, or intravenously. Beta-camera imaging (BCI) is a novel device for studying activity distribution in tissue specimens and, together with immunohistochemistry (IHC) with OC125, antifibrin, anticarcinoembryonic antigen, anti-cytokeratin, and anti-placental alkaline phosphatase antibodies, was used for correlation of activity distribution of tissue specimens. These results were in concordance: Antigen distribution measured with IHC and radioactivity distribution were similar with the same antibodies, antifibrin, and OC125: However, these antigens demonstrated rather different distribution. Tissue studies revealed that activity was concentrated also in the necrotic tumor tissue, indicating that cell death was also caused by radiation. Differences in the tumor cell morphology were observed using different routes of administration. With BCI, it is possible to quantitate activities in frozen sections (microdosimetry), and these results were in concordance with absolute activities as measured by tissue sampling and well-counting. Three-dimensional reconstruction of tissue slices combined with radioactivity distribution measured with BCI allows estimation of total absorbed radiation dose in tumor after an appropriate dose planning.

Tenascin in inflammatory conditions and neoplasms of the urinary bladder

Tenascin (Tn) is an extracellular matrix (ECM) glycoprotein strongly and widely expressed during embryogenesis. Tn is decreased in normal adult tissues but is reexpressed in numerous inflammatory, reparative and neoplastic processes. We immunostained samples of fetal and normal adult bladders and samples of bladder tissue from patients with chronic cystitis, detrusor hypertrophy, malakoplakia and transitional cell carcinomas (TCC) of all grades, with a monoclonal antibody (mAb) to Tn 143DB7. Sections of flat in situ carcinomas were also studied. In fetal bladders, strong and ragged Tn reactions were noted at the epithelial-stromal interface; in normal adult bladders, the reaction was delicate and less extensive. In chronic cystitis, Tn reactivity was enhanced particularly around prominent capillary blood vessels. In flat in situ carcinomas, Tn staining was stronger and more extensive than in normal mucosa but was often less extensive than in some examples of cystitis. In TCC I and II, Tn immunoreactivity was strong and predominated in the pericapillary stroma of the papillae; in infiltrating TCC II, comparatively limited Tn staining was noted. In deeply infiltrating grade III TCC with abundant stroma, Tn reaction was invariably strong and extensive, particularly around advancing tumor nests. The strongest Tn reactions were noted in invasive, high-grade TCC with abundant stroma. We conclude that in inflammatory-reactive processes, and in in situ carcinomas as well as in TCC, the extent and intensity of the Tn reaction correlates with the severity of the inflammatory infiltrate and with the extent of the stromal remodelling.

Local myotoxicity of bupivacaine in rabbits after continuous supraclavicular brachial plexus block

BACKGROUND AND OBJECTIVES

Local anesthetics including bupivacaine have been known to be myotoxic. Continuous brachial plexus blocks with bupivacaine provide good postoperative pain relief, but their effects on the surrounding muscles have not been studied.

METHODS

Eight rabbits were given continuous bilateral brachial plexus blocks with 0.25% bupivacaine (BUPI) and another eight (SALINE) equivalent volumes of saline infused into the plexus region under pentobarbital-ketamine sedation. At the end of the 24-hour blocks, muscle biopsies were taken from one side of the neck in both groups. A week later, the biopsy procedure was repeated on the other side. Plasma concentrations of bupivacaine were measured before and at the end of the 24-hour blocks.

RESULTS

Inflammatory cell infiltration and muscle fiber necrosis were significantly more common in the BUPI than in the SALINE group (p < 0.001). At the end of the continuous block, predominantly neutrophils were found, but in the BUPI group large amounts of eosinophilic granulocytes also were found. A week later lymphocytes, plasma cells, macrophages, and fibroblasts were seen as a sign of beginning scar formation. Plasma concentrations of bupivacaine at 24 hours were at a nontoxic level (0.28-0.71 microgram/ml).

CONCLUSIONS

Brachial plexus blocks with bupivacaine caused reversible myotoxicity and inflammation in the rabbit. A week after the continuous blocks, muscle fiber regeneration had already started.

Effects and acceptability of a new 17 beta-oestradiol-releasing vaginal ring in the treatment of postmenopausal complaints

The treatment of postmenopausal symptoms was studied in 26 healthy women using a new synthetic rubber (Kraton D 2109) vaginal ring containing 53 mg of 17 beta-oestradiol. All women were postmenopausal, at least 6 months after the last vaginal bleeding and suffering from daily hot flushes. The study was conducted in a double-blind placebo-controlled intrapatient cross-over fashion, and the study period was 6 months. The rings used give an initial in vitro release rate of 0.4 mg/E2 per day. The in vitro release rate decreases to about 0.2 mg/day after 20 days and levels off asymptotically to about 0.1 mg/day after 50 days. Serum E2 levels equivalent to the follicular phase of the normal menstrual cycle were measured after 1 month's use, and serum E2 level stayed above postmenopausal levels throughout the study period. FSH was suppressed during use of the E2-releasing vaginal ring, while LH showed no statistically significant suppression in continued use. Postmenopausal complaints were recorded by Visual Analogue Scales (VAS) as judged by both the patient and the examining doctor; all complaints had favourable outcomes during use of the E2-releasing vaginal ring without deterioration of symptoms during use of the placebo ring. No serious side-effects were encountered, and the possibility of managing all postmenopausal complaints with intravaginal oestrogen treatment is discussed.

Insulin-like growth factors and their binding proteins in benign and malignant uterine diseases

Evidence available supports the concept that the proliferative response of the uterus to oestrogen is through activation of local regulatory factors, IGFs amongst them. Oestrogen stimulates the expression of IGF-I and IGF-I receptor mRNAs, whereas progesterone induces the major endometrial IGFBP, IGFBP-1, which is proposed to act as an inhibitor of IGF actions in normal endometrium. Since both benign and malignant uterine diseases are related to oestrogen action, the hormonally regulated local IGF system may play an important role in the pathophysiology of uterine diseases. In support of this hypothesis, we found differences in the expression of IGFBP mRNAs and in the presence of translated IGFBPs between benign and malignant uterine tissues. Furthermore, receptor binding of IGF-I has been found to be higher in neoplastic uterine tissues compared to normal tissues.

Radioimmunotherapy with 90Y-labeled monoclonal antibodies in a nude mouse ovarian cancer model

Tumor stroma contains much fibrin, and so monoclonal antifibrin antibody can accumulate in tumors. We treated nude mice bearing human ovarian carcinoma xenografts with 90Y-labeled monoclonal antifibrin antibody Fab fragments administered intratumorally. The survival time vs. a control group was significantly prolonged and tumor growth rate was decreased. Another group of animals was treated with 90Y-labeled OC 125-monoclonal antibody; these mice received the antibodies intratumorally, intraperitoneally or intravenously. The survival time was longest in the intratumorally treated group. There was no significant difference in survival between 90Y-labeled OC 125 and antifibrin in the intratumorally treated animal groups. The tissue activity distribution studies revealed that bone marrow is the critical organ. Intratumorally injected monoclonal 90Y-antifibrin antibodies were retained at least 36 h (up to 50% of injected activity per gram tumor tissue) in the xenograft after one treatment, causing cell death. Beta-camera imaging and immunohistochemistry were performed for studies of the correlation between 90Y activity and fibrin distribution in tumor specimens. These results were in concordance. In conclusion, intratumoral administration seems suitable for radioimmunotherapy, with an antibody that targets stromal structures. The accumulation can be successfully monitored by a beta-camera.

Enhanced tenascin expression in cervical and vulvar koilocytotic lesions

Tenascin is an extracellular matrix glycoprotein that is widely expressed during embryogenesis. In adults, it is restricted to select sites, including certain epithelial-stromal interfaces, but is notably enhanced in active inflammatory-reactive processes and in the stroma of many neoplasms. The authors immunostained with the monoclonal antibody (MAb) 100EB2 cryosections of vulvar and cervical biopsies displaying convincing koilocytosis with variable degrees of hyperplasia-dysplasia; in situ carcinomas were included. The presence of human papillomaviruses (HPV) 6, 11, 16, 18, 31, or 33 was confirmed by in situ hybridization in a subset of cases. Findings were compared with normal controls. The study was extended with the MAb 143DB7 that reacted with tenascin in paraffin sections. In normal samples, tenascin immunoreaction appeared as a delicate, continuous rim, in the immediate vicinity of the laminin staining; in parakeratotic areas, the rim was thicker. In foci of hyperplastic-dysplastic epithelium with or without koilocytosis, a distinct increase in tenascin staining was noted; enhanced tenascin often paralleled increasing hyperplasia and dysplasia. In most cervical and vulvar carcinomas in situ, the reactions were intense and extended deeply and raggedly into the underlying stroma. Tenascin was selectively enhanced in the endocervical stroma around inflammed or metaplastic glands. The authors conclude that tenascin is increased in HPV infection associated with epithelial proliferation. Enhancement was most consistently strong and extensive in in situ carcinomas, suggesting a correlation with active phases of epithelial growth and stromal remodeling.

Technical and light microscopic comparison of four different small-diameter catheters used for continuous spinal anesthesia

BACKGROUND AND OBJECTIVES

Recently several manufacturers developed ultra-thin catheters for continuous spinal anesthesia. Their use may be associated with technical problems.

METHODS

Four spinal catheters [Preferred Medical 28-gauge and 32-gauge (polyurethane), Kendall CoSpan 28-gauge (nylon), and Microspinal 32-gauge (polyimide)] were compared in 41 patients who underwent knee or hip operations. Difficulties in using the catheters were recorded, and after their removal, the catheters were examined by light microscopy.

RESULTS

The insertion of the 28-gauge catheters was always successful. However, five of 11 of the 32-gauge polyurethane and one of ten of the 32-gauge polyimide catheters could not be inserted. Plain 0.5% bupivacaine (2-6.5 ml) was administered, and the median pinprick analgesia level varied between T4 (28-gauge nylon) and T7 (other groups). During removal, one of ten of the 28-gauge nylon, four of ten of the 28-gauge polyurethane, and all six 32-gauge polyurethane catheters stretched. Two of six of the 32-gauge polyurethane catheters broke, but no fragment remained in any patient. Microscopic examination revealed deposits of fibrinous material on the tips of all polyurethane and polyimide catheters and on one nylon catheter. One polyimide catheter ruptured 15 cm from the tip. No signs of tearing or lost pieces of catheter material were observed by light microscopy.

CONCLUSION

The use of the 32-gauge polyurethane catheter was associated with problems that limit its clinical usefulness. Nylon and polyimide catheters with stainless steel stylets were more resistant to stretching. The nylon catheter was most resistant to adhesion of fibrinous material.

The expression of CEA, CA 19-9 and HMFG antigens in ovarian clear-cell and endometrioid carcinomas

The tumour antigen expression of ovarian and endometrial endometrioid carcinomas, ovarian clear-cell carcinomas as well as endometrial and cervical clear-cell carcinomas were immunohistochemically compared. Of special interest were potential differences between the endometrioid and clear-cell carcinomas of the ovary. The expression of CEA and CA 19-9 tumour antigens in all these tumour types was heterogeneous, with 10-20% of the cases being positive for CEA and 40-75% being positive for CA 19-9. In contrast, HMFG IIIC 12, a monoclonal antibody originally directed against human milk fat globule (HMFG) membrane antigens, invariably detected a corresponding antigen on every case of these tumour types. Another HMFG antibody, SM IF 3, on the other hand, detected antigenic material on all clear-cell tumour types, but only rarely on endometrioid tumours of the ovary or endometrium. While HMFG IIIC 12 detects an antigen present on all ovarian, endometrial and mammary carcinomas, antibody SM IF 3 thus appears to be more restricted in its staining patterns. Our results with both of these antibodies indicate that ovarian clear-cell carcinomas and ovarian endometrioid carcinomas have antigenic differences, which provides further evidence that they belong to different tumour entities.

Luteal phase defect in habitual abortion: progesterone in saliva

OBJECTIVE

To re-evaluate the occurrence of luteal phase defect (LPD) in habitual abortion and to determine the value of salivary progesterone (P) assay in its diagnosis.

DESIGN

Prospective study on patients with a history of at least three consecutive miscarriages.

SETTING

Departments I and II of Obstetrics and Gynecology, University Central Hospital of Helsinki, Helsinki, Finland.

PATIENTS

Forty-six patients (27 primary and 19 secondary aborters) and 12 healthy control women without a history of abortion.

RESULTS

Eight patients (17.4%, 5 primary and 3 secondary aborters) exhibited a delay of greater than 2 days in endometrial maturation during two consecutive cycles, whereas in 38 patients (82.6%) endometrial maturation corresponded to the actual cycle day. Salivary P showed a distinct ovulatory rise, but no statistically significant differences were evident between patients (with or without LPD) and healthy control women.

CONCLUSIONS

An endometrial maturation defect may be a factor in 17.4% of patients with habitual abortion, but this cannot be detected by salivary P assay.

Human papillomavirus types 16 and 18 in adenocarcinoma of the uterine cervix

Many reports have shown a link between human papillomavirus (HPV) and cervical squamous neoplasia. However, the association of HPV with cervical adenocarcinoma has been studied less extensively. The authors evaluated the presence of HPV-DNA in 106 patients with adenocarcinoma of the uterine cervix by in situ hybridization, using 35S-labeled probes for HPV 16 DNA and HPV 18 DNA. The overall prevalence of HPV-DNA was 18% (19 of 106). HPV 16 was present in 2 (2%) cases, HPV 18 was observed in 15 (14%) cases, and both HPV 16 and HPV 18 were found in 2 (2%) cases. There was a correlation between HPV-DNA positivity and tumor stage (P less than 0.01) and tumor size (P less than 0.05), but there was no relationship between HPV-DNA positivity and tumor differentiation, proliferation (S-phase fraction), ploidy, lymph node metastases, or five-year survival rate. These results suggest that HPV 18 DNA is associated with cervical adenocarcinoma but the presence of HPV 18 has no influence on overall survival.

Steroid receptors and Ki-67 reactivity in ovarian cancer and in normal ovary: correlation with DNA flow cytometry, biochemical receptor assay, and patient survival

Steroid hormone receptors and reactivity for Ki-67 proliferation antigen were studied immunohistochemically in non-neoplastic post-menopausal human ovary and in 29 ovarian cancers. In the normal ovary, oestrogen (OR) and progesterone receptors (PR) were found in the surface epithelium and PR also in the ovarian stroma. Of the ovarian carcinomas 38 per cent (11/29) contained OR and 69 per cent (20/29) PR. Oestrogen receptor expression was confined to malignant cells, whereas PR was present occasionally also in the tumour stroma. In most cases, ORs and PRs were found only in a small population of cancer cells. The growth fractions assessed by the percentage of Ki-67-positive cells ranged from 1 to 59 per cent (mean 19.7 per cent) with a significant correlation (r = 0.74, P less than 0.0001) to S-phase values (mean 12.9 per cent, range 1.2-25.9 per cent) determined by DNA flow cytometry. High Ki-67 (greater than or equal to 15 per cent) and S-phase levels (greater than or equal to 7.5 per cent) correlated with advanced disease stage and patient survival but not with OR or PR status, suggesting that hormone-receptor pathways and proliferative activity are not related in ovarian cancer. Positive OR status, however, identified patients with a better prognosis (P = 0.02), suggesting a correlation with tumour differentiation. The independent prognostic value of oestrogen receptor status and Ki-67 remains to be determined, but the prognostic impact of Ki-67 was comparable to that of S-phase values.

Deoxyribonucleic acid flow cytometric analysis of cervical adenocarcinoma: prognostic significance of deoxyribonucleic acid ploidy and S-phase fraction

Paraffin-embedded tumor samples from 125 patients with cervical adenocarcinoma were analyzed by deoxyribonucleic acid flow cytometry. Thirty-one percent of the tumors were aneuploid. Triploid deoxyribonucleic acid content predominated (51.3%) and one third of the deoxyribonucleic acid aneuploid tumors were tetraploid, whereas near-diploid deoxyribonucleic acid aneuploidy was seen infrequently. Deoxyribonucleic acid aneuploidy was associated with tumor size, histologic grade, clinical stage, and high S-phase fraction. Deoxyribonucleic acid ploidy and S-phase fraction value were independent prognostic parameters, together with the presence of lymph node metastases and tumor size. In conclusion, our results indicate that flow cytometric deoxyribonucleic acid analysis helps to predict the prognosis and may thus influence the choice of treatment.

Adenocarcinoma of the uterine cervix

In Finland, the incidence of cervical cancer has shown a decreasing tendency since the 1960s. The same trend, however, has not been noticed in the incidence of cervical adenocarcinoma. The reason for this is not known, although many studies have shown differences in the cause, epidemiology, and biology of the epidermoid and adenocarcinoma of the uterine cervix. A total of 106 new patients with cervical adenocarcinoma were treated at our institution from 1976 to 1980, which represents 20.4% of all cervical carcinomas treated. The mean age of the patients was 58.1 years (range, 29 to 82 years) and the peak incidence was in the group 60 to 69 years of age. Most of the patients were postmenopausal (71.7%) and the main symptom was abnormal vaginal bleeding (78.3%). The proportion of Stage I was 61.3%. Combined operative and radiation therapy was used in 74.5% of the patients. The overall 5-year survival rate was 65.1% (corrected 74.5%), which did not differ from that of patients with squamous cell carcinoma. The most significant prognostic factors were the size of the tumor, presence of pelvic lymph node metastases, and the stage of the disease.

Ultrasound findings in uterine mixed müllerian sarcomas and endometrial stromal sarcomas

Sonographic findings in five cases of mixed mullerian tumors and two cases of endometrial stromal sarcoma which were evaluated before surgery for staging are reviewed. Assessment of myometrial invasion was in agreement with surgical findings in five cases; in the two other cases invasion was overestimated. The echo pattern of these tumors presented some peculiarities. In five patients, four with mixed mullerian tumors and one with endometrial stromal sarcoma, a heterogenous pattern with high-intensity and hypoechoic areas scattered in the myometrium was seen. In the other two cases the sonographic picture was indistinguishable from that of leiomyomas. Sonography is an accurate imaging technique for preoperative staging of uterine sarcomas. If an heterogenous echo pattern of the uterus as described is found at sonography, sarcoma should be suspected and laparotomy performed urgently.

Cytovillin, a microvillar Mr 75,000 protein. cDNA sequence, prokaryotic expression, and chromosomal localization

Cytovillin is a microvillar cytoplasmic peripheral membrane protein, with prominent expression in vivo in placental syncytiotrophoblasts and certain human tumors. Cytovillin cDNA was cloned from a human placental lambda gt11 library using affinity purified antibodies. The identity of cytovillin cDNA clones was confirmed by expression of cytovillin in Escherichia coli and using antibodies raised against the expressed fusion protein in comparison with antibodies against cytovillin purified from cultured human choriocarcinoma cells. In these cells Northern blotting analysis identified a major 3.5-kilobase cytovillin mRNA. The cDNA encodes a protein of 575 amino acids corresponding to a molecular weight of 68,084. According to secondary structure prediction, cytovillin is a hydrophilic protein with an extensive internal alpha-helical region ending in a sequence of 7 consecutive prolines. The predicted alpha-helical region showed limited homology to alpha-helical regions of cytoskeletal proteins and certain other proteins, but no extensive homologies were found in the cytovillin cDNA or the deduced amino acid sequence to other registered DNA or protein sequences. Southern blot analysis of a DNA panel of human mouse somatic cell hybrids localized the cytovillin gene to the end of the long arm of chromosome 6 (6q22-q27). Our results show that cytovillin is representative of a novel class of microvillar proteins.

Blastocyst implantation precedes induction of insulin-like growth factor II gene expression in human trophoblasts

The cytotrophoblast cell population of the human embryonic conceptus proliferates rapidly during the first month following blastocyst implantation. Since the trophectoderm lineage is established in preimplantation morula/blastocysts, the scenario underlying initiation and maintenance of the rapid proliferative phenotype of cytotrophoblasts is a central issue. The insulin-like growth factor II (IGF-II) gene is highly expressed in proliferative cytotrophoblasts of first trimester placenta and performs as a placenta growth factor. To establish a temporal correlation between IGF-II expression and initiation of highly proliferative trophoblasts in human development, we employed in situ hybridization analysis of the expression of the IGF-II and human chorionic gonadotropin beta-subunit (beta-HCG) genes in human pre- and postimplantation development. The data show that the appearance of high steady-state levels of IGF-II transcripts in trophoblasts is a postimplantation event, whereas beta-HCG transcripts can already be detected in preimplantation development. This observation makes a role for endogenously produced IGF-II in the normal development of preimplantation embryos unlikely, but suggests that endogenously produced IGF-II participates in the formation and subsequent expansion of the rapid proliferative phenotype of the trophoblastic shell, following implantation.

Expression of merosin, a tissue-specific basement membrane protein, in the intermediate trophoblast cells of choriocarcinoma and placenta

Merosin is a novel tissue-specific basement membrane-associated protein found in basement membranes of trophoblast, striated muscle and Schwann cells. In placental extracts, the immuno-reactivity for merosin was detected in a protein band of 80 kilodaltons, and a 65 kilodalton polypeptide fragment of merosin could be isolated from proteolytic digests of placenta. In the present study, we describe the expression of merosin in human choriocarcinomas and normal placentas using immunoperoxidase staining of paraffin-embedded tissues. All five choriocarcinomas studied show immunoreactivity for merosin. Tumor cells, exhibiting the morphology typical of the intermediate trophoblast, stained distinctly for merosin. The cytotrophoblast and syncytiotrophoblast cells in these tumors showed negligible or no staining. In second and third trimester human placentas, merosin immunoreactivity was found in large extravillar mononuclear trophoblast cells of the basal plate as well as in the trophoblast basement membranes of the chorionic villi. The results indicate that merosin is mainly expressed in the intermediate trophoblast cells of both neoplastic and normal origin, whereas almost no expression is seen in cytotrophoblast and syncytiotrophoblast. Consequently, it is suggested that the intermediate trophoblast may represent a third, independently differentiated trophoblastic cell type.

Contribution of vaginal scanning to sonographic evaluation of endometrial cancer invasion

Vaginal sonography was compared to abdominal sonography in predicting myometrial invasion in 23 women (mean age 59 +/- 9 years) undergoing hysterectomy due to endometrial cancer. Vaginal scanning prediction corresponded to histological findings in 87% (20/23) of the cases. In 2 cases the degree of invasion was underestimated and in 1 case overestimated by vaginal sonography. Abdominal sonography was accurate in 78% (18/23) of the cases. Vaginal scanning also improved the sonographic visualization of endometrium and cervical canal. However, in one case a superficial invasion of the cervix was missed by both methods of scanning. Furthermore, in another patient an ovarian cyst of 5 cm located in the upper pelvis was seen by abdominal but not vaginal sonography. We suggest that a sonographic work-up to assess endometrial cancer spread should include both methods of scanning.

Preoperative sonographic evaluation of endometrial cancer

Preoperative sonography was performed in 93 patients with a histologic diagnosis of endometrial cancer. Uterine volume was enlarged (mean, 164 +/- 143.7 cm3; range, 25 to 800) but did not significantly correlate with the degree of myometrial invasion. Endometrial echoes were identified in 93.5% of the cases. A significant correlation (p less than 0.01, Newman-Keuls test) was found between endometrial echoes volume and myometrial invasion. Myometrial invasion was correctly predicted by sonography in 80% of the cases. Polypoid intraluminal growth was the most common factor affecting sonographic accuracy. Sonographic staging was accurate in 91% of the cases. Sonography appears to be an efficient, economic, and practical tool for clinical staging of endometrial cancer.

Redistribution of Mr 75,000 plasma membrane protein, cytovillin, into newly formed microvilli in herpes simplex and Semliki Forest virus infected human embryonal fibroblasts

We have previously purified an Mr 75,000 protein from cultured human JEG-3 choriocarcinoma cells and showed that this protein is specifically confined to the cytoplasmic side of JEG-3 microvillar membranes. Recently, the Mr 75,000 protein, designated as cytovillin, was found to be expressed also in several other cultured human cell lines and strains, in which it was detected in microvillus-related structures. We now demonstrate the redistribution of cytovillin in herpes simplex type 1 (HSV-1) and Semliki Forest virus (SFV) infected human embryonal fibroblasts. Virus infection induced rapidly numerous microvilli on the apical cell surfaces, and cytovillin was enriched into these newly formed structures as shown by indirect immunofluorescence and immunoferritin electron microscopy. In mock-infected cells treated with the anti-cytovillin antibodies a small amount of ferritin particles and faint fluorescence was detected along the smooth plasma membrane. Only occasional cell surface protrusions were observed in these cells. The enrichment of the cytovillin was first seen 2 h after infection. The isoelectric point (IP) and the mobility of the cytovillin polypeptide in sodium dodecyl sulfate polyacrylamide gel electrophoresis was not altered after this redistribution, suggesting that the protein was not significantly modified during infection. Five RNA+ SFV mutants (ts-1, ts-2, ts-3, ts-5, ts-7) with temperature-sensitive defects in processing and transport of viral envelope glycoproteins to the plasma membrane induced microvilli at the restrictive temperature (39 degrees C) as the wild type virus.(ABSTRACT TRUNCATED AT 250 WORDS)

Corticotrophin-releasing factor in human placenta: localization, concentration and release in vitro

Corticotrophin-releasing factor (CRF) immunoreactivity was demonstrated by immunohistochemical staining in the cytotrophoblast of the early pregnancy placenta, in the decidua and in the amnion. This localization is different from that of adrenocorticotrophic hormone (ACTH) and beta-endorphin, which are present in the syncytiotrophoblast. The release of immunoreactive CRF was demonstrated from both early and term placental tissues in vitro. The mean amounts of CRF in the early and term pregnancy placental/decidual extracts were 0.99 +/- 0.5 ng/g and 19.7 +/- 3.1 ng/g, respectively. A slightly greater amount of CRF was found in extracts from term placentae and in cord venous plasma collected after spontaneous vaginal delivery than in those collected at elective caesarean section performed before the beginning of labour.

Tumor-associated alpha-2-macroglobulin in human melanomas

We and others have previously shown that human melanoma cell lines in culture synthesize alpha-2-macroglobulin (alpha 2M). We have now studied melanomas from 30 patients for the presence of alpha 2M using the peroxidase anti-peroxidase technique on histologic sections from paraffin-embedded tissues and primary antibody raised against tumor-associated alpha 2M in rabbits. alpha 2M was detected in 10 of the 30 melanomas studied. In all but 2 cases the presence of alpha 2M was restricted to solitary tumor cells or to solitary foci of tumor tissue. In one case of melanoma almost all tumor cells were positive for alpha 2M, while in the others between 20% and 50% of tumor cells were positive. In all but one of the melanomas, the positivity was characteristic of epithelioid or large-cell type or was confined to this component in melanomas with more than one cell type. In 4 positive cases, differences in the extent of alpha 2M-containing tumor tissue were observed between primary tumor and metastases or metastases from different localizations, with equivocal trend. Clinical follow-up of the melanoma patients suggested that alpha 2M-positively tends to correlate with an unfavorable prognosis.

Microvillus-specific Mr 75,000 plasma membrane protein of human choriocarcinoma cells

We have previously purified from cultured JEG-3 choriocarcinoma cells an Mr 75,000 protein, originally detected using antibodies to a retrovirus-related synthetic peptide. Using polyclonal antibodies, we have now localized this protein immunocytochemically in JEG-3 cells at both light and electron microscopic levels. In immunofluorescence microscopy of saponin-permeabilized cells, the antigen appeared as dots and short strands at the apical cell surface. In pre-embedding immunoperoxidase electron microscopy, the Mr 75,000 protein was specifically localized to microvilli on the apical cell surface. Immunoferritin electron microscopy was used to assess more quantitatively the antigen distribution in the plane of the plasma membrane, and to define the position of the antigenic site(s) with respect to the membrane. The immunoferritin results confirmed the microvillus specificity of the Mr 75,000 protein and showed that the antigenic portion of the protein is within a few nanometers from, and on the cytoplasmic side of, the lipid bilayer. In detergent extraction experiments, the Mr 75,000 antigen was highly enriched in the soluble fractions. These results demonstrate that the Mr 75,000 protein is a membrane protein highly specific for microvilli.

Studies on the elevated amniotic fluid SP1 in Meckel's syndrome: modified glycosylation of SP1

Pregnancy-specific beta 1-glycoprotein (Schwangerschaftsprotein, SP1) is elevated in the amniotic fluid in Meckel's syndrome. In an attempt to clarify this phenomenon, we studied fetal tissues by immunohistochemistry for the distribution of SP1 in normal fetuses and fetuses with Meckel's syndrome. The amount of SP1 was increased in two out of ten Meckel placentae, as semiquantitatively shown by the immunoperoxidase method, but was normal in the rest of the cases. There was no difference in the SP1 distribution or content in the other fetal tissues studied. Fetal cerebrospinal fluid contained only very low levels of SP1 and thus cannot provide a source for elevated amniotic fluid SP1. In addition, binding of amniotic fluid SP1 to concanavalin A (Con-A) was studied in pregnancies with normal fetuses and Meckel's syndrome using affinity chromatography. The proportion not bound to Con-A in normal amniotic fluids decreased with advancing gestation and was lowest when the total SP1 concentrations were highest. An especially low percentage of SP1 not bound to Con A was found in Meckel's syndrome, suggesting an altered carbohydrate structure of SP1 in these amniotic fluids.