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The entire coding region of an ovine endometrial oxytocin receptor (OTR) cDNA was generated by PCR, subcloned into the SV40 major late promoter expression vector pSVLJ and transiently expressed in Cos-7 cells. A specific OTR antagonist, 125I-labelled d(CH2)5 [Tyr(Me)2,Thr4,Tyr-NH29]-vasotocin (OTA), was used to describe the binding kinetics of the expressed receptor which had a Kd of 4·5 nm and Bmax of 2·4 nm/mg protein (6·8 × 105 receptor molecules/transfected cell). The functional properties of the expressed OTR were determined by measuring oxytocin-induced phosphoinositide (PI) hydrolysis. Oxytocin increased PI turnover in OTR transfected cells fourfold in excess of residual endogenous activity, and stimulated phospholipase C (PLC) activity in a dose- and time-dependent manner, confirming that the expressed OTR cDNA was functional. Arginine vasopressin also stimulated PI turnover in a dose-dependent manner; thresholds of responses to oxytocin and arginine vasopressin were 10−9 m and 10−7 m respectively. OTA did not increase PI turnover and competitively inhibited the oxytocin-induced response. Direct activation of the pathway by aluminium fluoride and guanosine (3′-Othio)-triphosphate (GTPγS) confirmed that the OTR was G-protein linked. Co-incubation of GTPγS with oxytocin shifted the PI-response threshold from 10−7 m to 10−9 m and significantly increased the level of response, suggesting that maximum PI turnover was agonist-dependent. The G-protein involved in mediating the signal transduction pathway was pertussis toxin-insensitive and, therefore, probably a member of the Gq subfamily. The PLC inhibitor, U73122, had no effect on oxytocin-induced PI turnover, consistent with the response in endometrial tissue. These data suggest that the signalling pathway mediated by expressed OTR is similar to that attributed to OTR occupancy in ovine endometrium. Journal of Endocrinology (1996) 149, 389–396

A bovine trophoblast interferon (IFN-τ) gene promoter sequence (− 450 to +26 bp relative to the transcription start site) led to expression of reporter gene (CAT) constructs transfected into L929 (murine fibroblast) or JAR (human choriocarcinoma) cells. Expression depended on the presence of an exogenous (SV40) enhancer. Poly(I)(C) activated endogenous IFN production in L929 and JAR cells but had no consistent effect on CAT expression. Similar results were obtained in L929 cells with inactivated Newcastle disease virus. There was no 'priming' effect of exogenous Type I IFN. Deletion mutants revealed sites exerting negative control on expression between −338 and −247 bp, and between −150 and −71 bp; these regions contained sequences resembling previously identified negative regulatory domains. In the absence of viral inducibility it is proposed that negative regulation contributes towards the stringent control of expression characteristic of IFN-τ genes.

Between January 1980 and October 1983, 417 patients were randomized for mastectomy followed by axillary node sampling or full axillary clearance. The aim of the study was to determine whether a standard ‘four-node’ axillary sample, followed by careful dissection of removed tissue, could accurately indicate the extent of local treatment required. Axillary radiotherapy was given only to patients with histological involvement of sampled nodes and not to any having axillary clearance. The incidence of involved nodes was similar for both groups, as were distant relapse and survival rates. Currently 62.6 per cent are alive after clearance and 65.0 per cent after sampling. A non-significant increase in the rate of locoregional relapse was observed for those treated by axillary node clearance, this being due mainly to increased relapse on the unirradiated chest wall (clearance 21 per cent versus sampling 12 per cent in patients with node-positive disease). There was only a minor difference in axillary relapse, favouring axillary clearance (3.0 versus 5.4 per cent). In patients with operable breast cancer, mastectomy with axillary node sampling gives equal control to mastectomy with axillary node clearance but, as morbidity is greater, surgical clearance of the axilla is the preferred option.

A sheep endometrial oxytocin receptor (OTR) cDNA (1·5 kb) was isolated from a λ-ZAP library using a reverse transcription-PCR product probe generated from oestrous endometrial mRNA. The sheep OTR cDNA shared an overall similarity of 82% with human OTR cDNA, 85% with pig OTR cDNA and 76% with rat OTR cDNA. The encoded receptor was a 391 amino acid polypeptide 94% similar to human OTR, 94% similar to pig OTR and 93% similar to rat OTR. The sheep OTR contained two additional amino acids compared with human OTR which were located in the highly GC-rich third intracytoplasmic loop. This region is thought to be associated with G protein coupling and signal transduction. Expression of the cDNA in Cos-7 cells and measurement of oxytocin-induced phosphoinositide turnover confirmed that it coded for a functional product. The affinity of the expressed receptor was comparable with that observed for the in vivo receptor.

A synthetic 45-mer oligonucleotide corresponding to part of the ovine endometrial oxytocin receptor cDNA was hybridized to sections of ovine uterus collected from 40 ewes at different stages during the oestrous cycle, the first 3 weeks of pregnancy and seasonal anoestrus. The quantity of oxytocin receptor mRNA was measured as the optical density (OD) value on autoradiographs using image analysis. Message first appeared in the luminal epithelium on days 14–15 of the cycle, increasing to a peak OD of 0·48 at oestrus and decreasing again between days 2 and 5. Oxytocin receptor mRNA in the superficial glands, deep glands and caruncular stroma increased between day 15 and oestrus to peak OD values of 0·17, 0·11 and 0·11 respectively, declining again by day 2 and reaching basal values (ODs.e.m.) on days 0–1, but the change was not significant. In pregnant ewes there was no detectable oxytocin receptor mRNA on days 14–15 in any region, but hybridization to the luminal epithelium was present in two of three ewes on day 21. In anoestrous ewes oxytocin receptor mRNA concentrations in all areas of the endometrium were approximately half those measured at oestrus. Optical density readings for oxytocin receptor mRNA in the various uterine compartments were compared with measurements of oxytocin receptors in the same regions as assessed by binding studies using the 125I-labelled oxytocin antagonist d(CH2)5[Tyr(Me)2,Thr4,Tyr-NH29]-vasotocin (125I-labelled OTA). In the endometrium, receptor mRNA and 125I-labelled OTA binding patterns changed in parallel, and both sets of measurements were significantly correlated (P125I-labelled OTA binding occurred at oestrus; this was not accompanied by a similar increase in oxytocin receptor mRNA hybridization. This study helps to confirm that the previously identified cDNA clone is derived from the ovine oxytocin receptor, as patterns of oxytocin receptor mRNA expression in the endometrium closely resembled those of oxytocin binding. Maximum expression and binding both occurred at oestrus, suggesting that regulation of the oxytocin receptor gene in the uterus occurs principally at the transcriptional, rather than at the translational, level. Failure to detect a significant increase in myometrial mRNA expression at oestrus may indicate that the endometrial and myometrial oxytocin receptors are of different isoforms.

We have cloned a 2.4-kb cDNA containing the complete coding sequence of ovine Mx from a lambda ZAP library constructed using RNA from the endometrium of a normal sheep on day 16 of pregnancy. Ovine Mx shows 80% similarity to human MxA. Human and mouse Mx are type-1 interferon (IFN)-induced genes that have previously been shown to confer resistance to influenza virus. The ovine Mx cDNA contains an open reading frame of 1962 nucleotides (nt) coding for a 653-amino-acid (aa) protein. The deduced translated sequence has consensus GTP-binding sites and similarity to the human MxA sequence (RKFLKERLARL) that has been shown to be essential for resistance against vesicular stomatitis virus (VSV). The presence of Mx mRNA was investigated by Northern blot analysis in the endometrium of non-pregnant sheep and between days 8 and 127 of pregnancy. Mx expression was detected at high levels between day 13 and day 20 of pregnancy. Furthermore, eightfold higher levels of Mx mRNA were detected in the pregnant versus the non-pregnant uterine horn in unilaterally pregnant sheep. Mx mRNA can be induced in sheep endometrium by ovine trophoblast interferon (IFN-tau).

The polymerase chain reaction (PCR) was used to generate a 131 bp cDNA encoding part of the sheep endometrial oxytocin receptor. The nucleotide sequence of this cDNA was 93.8% identical to the human oxytocin receptor sequence in this region. When used to probe Northern blots of sheep endometrial RNA the PCR product identified a 6.7 kb mRNA which appeared and disappeared during the oestrous cycle in parallel with the oxytocin receptor molecule as measured by ligand binding. The sheep endometrial receptor mRNA was significantly larger than the human myometrial mRNA (4.7 kb). It is suggested that the cloned cDNA described here is an appropriate probe for use where it is required to measure sheep oxytocin receptor mRNA.

Background and Methods: The Scottish Adjuvant Tamoxifen Trial (main trial) was initiated in April 1978 to assess the effect of tamoxifen given to patients with breast cancer immediately after mastectomy (or mastectomy plus radiation therapy) (adjuvant arm) or only after the patients had had a relapse (control arm); 1323 patients were randomly assigned (667 to the adjuvant arm and 656 to the control arm). Results have been reported for the follow-up period from 2.5 through 8 years. In this article, we report updated results after a median follow-up of 15 years. If agreeable and eligible, patients who were disease free at 5 years in the adjuvant arm of the main trial were entered into a duration trial and randomly assigned either to stop taking tamoxifen (169 patients) or to continue taking it indefinitely until relapse or death (173 patients). For this update, we analyzed information on death, recurrence, survival, and other malignancies for all but 21 of the 560 living patients from the original and duration trials to determine the probabilities of total survival, systemic relapse of disease, and death from breast cancer. All statistical tests are two-sided. Results: The beneficial effect of adjuvant tamoxifen given for 5 years on the probability of total survival (P = .006), systemic relapse (P = .007), and death from breast cancer (P = .002) has been maintained through 15 years. No additional benefit was observed in those randomly assigned to continue taking tamoxifen beyond 5 years. Conclusion: Information from this study suggests that, if adjuvant tamoxifen is given to women with operable breast cancer, it need not be for more than 5 years.

Inherited retinal degenerations such as retinitis pigmentosa (RP) are characterized by progressive death of the photoreceptors due to apoptosis. To identify changes in gene expression associated with the degenerative state in RP retinas, expression profiling of apoptosis-related genes was performed using a gridded array technique.Total RNAs from RP and control retinas were used to generate radiolabeled cDNA probes to screen gridded membrane arrays of 205 apoptosis-related genes. Reverse transcription-polymerase chain reaction was used to generate probes corresponding to differentially expressed genes for Northern blot analysis and for mRNA in situ hybridization studies of retinal cryosections. Fluorescence immunocytochemistry was performed on retinal sections using available antibodies.By expression profiling, we identified upregulated expression of the mRNA for secreted Frizzled-related protein-2 (SFRP2) in RP retina in comparison with control. By Northern blot analysis, SFRP2 mRNA levels were 2- to 20-fold higher in RP samples than in controls. The localization of SFRP2 mRNA by in situ hybridization varied according to the degree of degeneration, from stratified in relatively well-preserved retinas to diffuse in the highly degenerative state. By immunofluorescence, SFRP2 protein in RP retinas was found mainly to colocalize with the cell adhesion and signal transducing protein beta-catenin.SFRPs can regulate apoptosis in vitro and appear to interact with the Wnt/Frizzled signaling pathway, which includes routes to apoptotic activation. Increased SFRP2 expression in RP retinas suggests that an altered pattern of Wnt signal transduction may be a step in the degenerative process linking causal mutations with eventual photoreceptor demise.

The interaction of cells with the extracellular matrix plays a critical role in morphogenesis and cell differentiation. To define how Schwann cells might interact with the extracellular matrix, we chose to study the expression of the laminin/collagen receptor alpha1beta1 integrin during nerve development in the rat from embryonic day 14 to maturity. We found that this integrin is expressed predominantly on mature non-myelin-forming cells and only at very low levels on myelin-forming cells. Significant levels of this integrin were not detected on Schwann cell precursors or embryonic Schwann cells in vivo. Experiments using transected and crushed sciatic nerve showed that alpha1beta1 integrin expression is regulated at least in part by axonal contact. Furthermore, Schwann cell culture experiments showed that alpha1beta1 integrin levels are strongly upregulated by transforming growth factor-beta(s) and phorbol esters.

To determine whether, when primary breast cancer is treated by local excision supported by systemic therapy appropriate to the oestrogen receptor status (ER) of the tumour, local radiotherapy can be avoided.We carried out a randomised controlled trial in 585 patients aged less than 70 years with primary breast cancers of 4 cm or less in size in four specialist units and seven other hospitals in Scotland. After local excision of the tumour (1 cm margin) and an axillary lymph-node clearance or sample, all patients received systemic therapy with oral tamoxifen 20 mg daily or six 3-weekly intravenous bolus injections of cyclophosphamide 600 mg, methotrexate 50 mg, and fluorouracil 600 mg per m2, depending upon the ER concentration in the primary tumour. Patients were then randomly allocated to postoperative radical radiotherapy (50 Gy to breast with boost to the tumour bed) or to no further local treatment. The median follow-up of living patients was 5.7 years. The primary analysis was by intention to treat but since some patients did not receive systemic therapy appropriate to their ER status, a subsidiary analysis was restricted to 464 patients in whom all details of the protocol had been observed.In the primary analysis survival was equal in the radiotherapy and non-radiotherapy groups (hazard ratio [HR] 0.98, 95% CI 0.67-1.44). Event-free survival showed an advantage in the irradiated patients (HR 0.54, 95% CI 0.39-0.74), largely due to fewer loco-regional relapses (HR 0.20, 95% CI 0.12-0.33). The relapse rate in the ipsilateral breast was 24.5% in the non-irradiated group and 5.8% following breast irradiation. The subsidiary analysis confirmed these findings and indicated the advantage of radiotherapy irrespective of ER concentration. There was a non-significant trend towards fewer distant metastases in the irradiated group.After local excision of a primary breast cancer, we conclude that radiotherapy to the residual breast tissue is advisable even when selective adjuvant systemic therapy is given.

In 1985 a second randomisation was initiated for women in the treatment arm of the Scottish Tamoxifen Trial either to stop tamoxifen at 5 years or to continue indefinitely. A preliminary analysis of outcome in 342 patients at a median follow-up of 6 years suggests that a worthwhile gain in disease control from continuing adjuvant tamoxifen beyond 5 years is unlikely. [Hazard ratio for events (relapse or death without relapse) is 1.27, 95% CI = 0.87 - 1.85.] There is a suggestion that therapy for longer than 5 years may increase the risk of endometrial carcinoma (P = 0.064).

OBJECTIVE--To determine any cardiac or vascular morbidity associated with long term treatment with tamoxifen given after mastectomy for primary breast cancer. DESIGN--Cohort study using linkage between database of a randomised trial and statistics of Scottish hospital inpatients to identify episodes of cardiac and vascular morbidity. SETTING--NHS hospitals in Scotland. SUBJECTS--1312 women who had undergone mastectomy for breast cancer and who were randomised either to a treatment group to receive adjuvant tamoxifen or to a control group to be given tamoxifen only on first relapse of disease. Maximum duration of tamoxifen treatment was 14 years. Total woman years of follow up were 9943. MAIN OUTCOME MEASURES--Randomised and observational comparisons of risk (expressed as hazard ratios) of myocardial infarction, other cardiac event, cerebrovascular disease, or thromboembolic event according to treatment allocated and between nonusers, former users, and current users of tamoxifen. RESULTS--Use of tamoxifen was associated with lower rates of myocardial infarction. Hazard ratio for women in control group was 1.92 (95% confidence interval 0.99 to 3.73) compared with women allocated to adjuvant treatment. The association was stronger for current use: hazard ratio for non-users was 3.49 (1.52 to 8.03) compared with current users. Current users of tamoxifen, however, had higher rates of thromboembolic events:hazard ratio for non-users was 0.40 (0.18 to 0.90) compared with current users. CONCLUSIONS--Our results provide further evidence that tamoxifen reduces the risk of myocardial infarction. Thromboembolic events should be carefully monitored in trials of tamoxifen, particularly those of prophylactic treatment, in which tamoxifen is given to healthy women.

The sheep endometrial oxytocin receptor plays a central role in determining the time at which luteolysis occurs during the oestrous cycle, and in the events leading to the establishment of pregnancy (the maternal recognition of pregnancy). Expression of the receptor in the uterus is controlled by ovarian steroid hormones, and by trophoblast interferon (IFN-tau). We report here studies on the second messengers involved in the effect of IFN-tau, and on the structure and expression of the oxytocin receptor. The receptor is expressed in ovine endometrial explants during culture, when the explants are taken during the luteal phase of the cycle; this process is partially blocked by inhibitors of protein kinase C, or by down-regulation of protein kinase C. Therefore it is suggested that protein kinase C, rather than tyrosine kinases, is involved in the effect of IFN-tau on oxytocin receptor expression. Northern blotting shows that in common with uterine oxytocin receptor mRNA in other species, the message is heterogeneous. cDNA sequencing indicates the sheep uterine oxytocin receptor is at least 2 amino acids longer than those of other species, and expression of the receptor in Cos-7 cells induces oxytocin responsiveness in terms of phosphoinositide turnover.

This paper describes the results of a national survey on the non-surgical treatment of early breast cancer in the UK relating to the management of ductal carcinoma in-situ (DCIS), and the rationale for the current status of the UK DCIS trial. The survey shows that there is considerable clinical uncertainty, which can only be resolved by the trial.

The oxytocin receptor, a seven transmembrane domain, G protein-linked receptor molecule, plays a central role in determining the endocrine function of the ruminant uterine endometrium. During non- pregnant cycles the control of this molecule by circulating steroid hormones leads to regression of the corpora lutea. The kinetics of the mechanisms involved determine the time at which luteolysis occurs, and therefore the length of the oestrous cycle. In pregnancy, secretions of the trophoblast block endometrial oxytocin receptor gene expression and lead to luteal maintenance. An understanding of the molecular mechanisms involved in the steroidal control of oxytocin receptor gene expression will provide an explanation for the relative constancy of oestrous cycle lengths in non-pregnant animals. Unravelling the way in which trophoblast products block expression of the oxytocin receptor gene will lead to a better understanding of the reasons for the high rate of embryonic loss in domestic ruminants.

This report gives the responses of general surgeons in Scotland to two questionnaires. Satisfactory rates were obtained: 82% for the more detailed survey in 1988 and 62% for the second survey (1991), where nonrespondents were not followed up. In 1988 the rationale was the poor participation in the Scottish breast conservation trial while the 1991 survey further investigated the diversity of surgical opinion identified in the first. The limited trial support in 1988 was mainly due to reluctance to accept all treatment options. The majority were prepared to consider trial participation although 47% believed this compromised doctor-patient relationships. Although breast-conserving therapy was widely supported, many different views on management were encountered, both in the degree of influence of specific factors and in the decisions taken in relation to them. We believe these surveys have re-inforced a need for management guidelines, particularly as around half the patients with symptomatic breast cancer were being treated in non-specialist units.

The endometrial oxytocin receptor occupies a central point in the choice between luteolysis and pregnancy in ruminants. Receptor expression determines the time at which luteolysis occurs in nonpregnant animals, and thereby determines the duration of the oestrous cycle. Inhibition of receptor expression by trophoblast interferon (IFN) blocks the process of luteal regression and leads to continued progesterone secretion and the successful growth of the conceptus. Trophoblast IFN is probably required from the time of normal luteolysis during the cycle until luteal oxytocin concentrations of pregnancy decline, thus removing the stimulatory mechanism for the release of the episodes of prostaglandin F2 alpha required for luteolysis.

This paper presents results, 5 years after closure, of a randomized trial comparing adjuvant with postrelapse tamoxifen in 747 women with histological node-negative breast cancer. Two hundred thirty-six disease-free patients on adjuvant therapy were secondarily randomly assigned at 5 years to stop or to continue tamoxifen until relapse. Adjuvant tamoxifen, taken for a median duration of 60 months, has significantly prolonged disease-free survival overall (P = .0001), in the 214 premenopausal group (P = .018), in the 533 postmenopausal group (P = .0026), and for the 246 patients with estrogen receptor levels greater than 19 fmol/mg of protein (P = .0032); distant relapse has also been delayed overall (P = .029). Total survival comparison by Kaplan-Meier life-table analysis shows a nonsignificant trend in the same direction (P = .07). Adjuvant tamoxifen has also reduced the incidence of contralateral breast cancer and of death from myocardial infarction. No increase in the incidence of endometrial cancer has been found.

A brief resume of adjuvant endocrine therapy for operable breast cancer is given. This was first suggested in the 1930's but has only become accepted in the last 10-15 years. The reason for the lack of survival benefit in the first randomised trial, which began in 1948 in Manchester, was thought to be due to the increasing use of hormone therapy for metastases. Revival of interest came with the survival gain reported in the Toronto ovarian trial and the success in post-menopausal patients of the non-toxic anti-oestrogen tamoxifen. The different dose schedules used in the various large tamoxifen trials could explain the confusingly variable results in the literature. Combined analysis of trial results indicates that CMF is the adjuvant therapy of choice for pre-menopausal patients but this therapy may in part be acting through the ovaries. The Scottish and NATO trials have an overall survival advantage from adjuvant tamoxifen, even in pre-menopausal patients, and both have shown results to be independent of oestrogen receptor (ER) status. Whether the extra 3 years given in Scotland adds an additional benefit over the more commonly used 2-year course is uncertain. A statistically invalid look at selected data in the Scottish trial suggests that, in ER positive cases, post-relapse tamoxifen may have as great an effect on total survival as adjuvant use, a finding similar to that suggested by the first ovarian ablation trial and one requiring continued review.

Southern blotting of bovine genomic DNA indicated the presence of at least 3 bovine tIFN genes. The full DNA sequence of one of these genes, thought to be expressed in trophoblast, has been determined, including 193 bp of 5' non-coding region. The inferred amino acid sequence of bovine tIFN is more similar to ovine tIFN (80%) than to bovine IFN-alpha II (70%). The 5' flanking sequence has some similarity with bovine IFN-alpha II, and may contain a viral response element. A recombinant bovine alpha I interferon (Ciba Geigy; brIFN), resembling tIFN, extended oestrous cycle length in sheep when administered by intrauterine infusion over the period, Days 12-15 after oestrus, when maternal recognition of pregnancy occurs. Intramuscular injection was only effective at the doses used if given over a longer period (i.e. Days 9-15). Our experiments indicate that both tIFN and brIFN inhibit luteolysis by preventing a rise in endometrial oxytocin receptor concentrations, and suggest that tIFN achieves this by extending the time for which progesterone suppresses oxytocin receptor development. Further studies are required to confirm this hypothesis and to elucidate the interaction of the effects of progesterone and tIFN in endometrial cells.

The establishment of pregnancy in domestic ruminants depends upon the continued secretion of progesterone by the corpora lutea. In non-pregnant cycles the corpora lutea regress between days 12-15 after oestrus in the sheep; this process must be blocked to ensure continued exposure of the uterus to progesterone. This review discusses the evidence that embryonic products are involved in the maintenance of corpus luteum function, the identification of factors which may be responsible for this maintenance and the probable mechanism of action. The discussion centres on the recent identification of a trophoblast interferon which is thought to be the major trophoblastic factor preventing luteolysis in sheep and cattle.

Analysis of ovine conceptus RNA by slot blotting, Northern analysis and nested polymerase chain reaction failed to detect oxytocin–neurophysin prohormone mRNA. Probes used hybridized with both the 3' end of the prohormone mRNA and the oxytocin-coding sequence. Northern analysis of bovine and porcine conceptus RNA was also negative, and polymerase chain reaction demonstrated oxytocin–neurophysin mRNA in ovine corpus luteum, but not in human corpus luteum or decidua, or in ovine endometrium. Infusion of oxytocin into the uterine lumen in cyclic ewes between days 9 and 19 or 20 after oestrus failed to prolong the luteal phase of the cycle and had no effect on endometrial oxytocin receptor concentrations or uterine prostaglandin F secretion. Oxytocin administered systematically prevented luteolysis and reduced uterine prostaglandin F secretion. Taken together, these data suggest that blastocyst-derived oxytocin is unlikely to contribute to corpus luteum maintenance in early pregnancy. They are inconsistent with a previous report that the ovine blastocyst synthesizes and secretes oxytocin. Journal of Endocrinology (1991) 130, 443–449

Late-pregnant goats were separated into two groups. A control group of four goats had small (approximately 3 ml) volumes of secretion expelled from one mammary gland at infrequent intervals between day 130 of gestation and parturition. An experimental group of five goats had as much secretion as possible removed from both glands twice daily beginning on day 137 of gestation and continuing until parturition. After parturition, both groups were milked twice daily. Regular 'milking out' before parturition stimulated secretion of triglyceride by the mammary gland, and most of the fatty acids secreted in the triglyceride before parturition had a chain length of 18 carbons. Secretion of 6-14-carbon chain-length fatty acids in the milk triglycerides increased after parturition. There was no evidence that the onset of secretion of medium-chain and long-chain fatty acids occurred at different times in the control animals. It is concluded that the onset of secretion of medium-chain and long-chain fatty acids in milk triglycerides can be dissociated, although both are normally synchronized with parturition. Removal of secretion by the offspring at parturition may be a stimulus for the onset of secretion of long-chain fatty acids, but the onset of secretion of medium-chain fatty acids is brought about by some other mechanism.

The treatment of lactating goats with ACTH (single intramuscular injection) or cortisol (systemic infusion) resulted in an increase in milk yield and in the secretion of lactose, citrate and glucose into milk. The concentration of glucose in arterial plasma was also increased, resulting in a greater supply of glucose to the mammary gland. After ACTH treatment mammary uptake of glucose from the circulation did not increase and the balance between mammary uptake of glucose from blood and mammary output of glucose 'equivalents' into milk was significantly reduced. The results show that ACTH and cortisol can increase milk yield and lactose secretion by altering mammary metabolism of glucose. J. Endocr. (1984) 101, 203–211

A prospective study has been carried out in 172 women to determine the sensitivity of methods to detect occult metastatic disease in the skeleton and liver. With the exception of bone scintiscans, the results of these tests bore little relationship to recurrence rates. On the other hand, knowledge of the histopathology of the lower axillary (pectoral) lymph nodes is of value in this respect. A follow-up study is also reported which confirms the importance of accurate measurements of the primary tumour clinical node status and oestrogen receptor contact of the tumour in defining prognostic groups. Elastosis (estimated in 165 tumours) did not prove to be a useful prognostic index.

Slices of caruncular endometrium from steroid-treated ovariectomized sheep were incubated with myo-[2-3H]inositol to label tissue phosphatidylinositol. Effects of oxytocin were determined on the rate of incorporation of radioactivity into phosphatidylinositol and on the hydrolysis of phosphoinositides to inositol phosphates and diacylglycerol. Incorporation of radioactivity into phosphatidylinositol was linear during 2 h incubations; 10(-7) M (100 nM)-oxytocin caused a 2.8-fold increase in the rate of incorporation. In the presence of Li+, addition of 10(-7) M-oxytocin to slices in which phosphatidylinositol was pre-labelled caused mean increase of 40-fold in the incorporation of radioactivity into inositol mono-, bis- and tris-phosphates. Inositol 1,3,4-trisphosphate was quantitatively the major trisphosphate formed. The action of oxytocin on phosphoinositide hydrolysis was dose- and time-dependent, occurring at concentrations within the range observed in plasma during episodes of secretion in vivo, and with a time course comparable with that of the action of oxytocin on uterine prostaglandin production. The effect of oxytocin on incorporation of radioactivity into inositol phosphates was not affected by inhibitors of prostaglandin synthesis. Diacylglycerol 1- and 2-lipases in caruncular endometrium converted up to 72% of added 2-[3H]arachidonyldiacylglycerol into [3H]arachidonic acid during 30 min incubations at pH 7.0. Caruncular endometrium contained 1.49 mumol of phosphatidylinositol/g, representing approx. 0.2 mumol/g of phosphatidylinositol arachidonic acid. It is proposed that the stimulation of endometrial prostaglandin synthesis by oxytocin is accounted for by increased hydrolysis of phosphoinositides to diacylglycerol and inositol phosphates with subsequent release of arachidonic acid from diacylglycerol.

A histological review of 1003 invasive breast carcinomas identified 51 tumours in which the invasive component showed a predominantly cribriform pattern. These separated into two groups; 35 which showed exclusively cribriform or cribriform with a limited extent of tubular invasive elements only, designated 'classical' invasive cribriform carcinoma and 16 which also contained areas of less well differentiated invasive carcinoma, designated 'mixed' invasive cribriform carcinoma. At follow-up, 10 to 21 years after diagnosis, none of the 35 patients with classical invasive cribriform carcinoma had died as a result of this initial carcinoma and 30 remained alive. Of the 16 remaining patients, whose tumours showed areas of less well differentiated carcinoma, only six remained alive. However, the adjusted 10 years survival rate of these patients in this mixed group was significantly better than that of invasive carcinoma in Edinburgh. Invasive cribriform carcinoma in its classical form, is a histological subgroup of invasive carcinoma with the same excellent prognosis as that of invasive tubular carcinoma.

A cloned cDNA has been isolated by probing a sheep blastocyst cDNA library using a synthetic oligonucleotide representing the N-terminal amino acid sequence of the antiluteolytic protein, ovine trophoblast protein-1. Sequence analysis of the cDNA confirms the 70% homology between the antiluteolysin and the interferon-α family of proteins; however, the sequence reported here differs at several points from previously reported amino acid and cDNA sequences for the antiluteolysin. In-vitro translation of day-16 poly(A)+ RNA indicated that antiluteolysin mRNA is a major constituent of total mRNA at this stage of blastocyst development, and Northern blotting confirmed that antiluteolysin mRNA production occurred between days 13 and 22 after oestrus. This is consistent with the stage at which embryonic extracts are antiluteolytic on administration in vivo. These and other data confirm that the ovine trophoblast antiluteolysin is an interferon, and suggest that at least five isoforms of this protein may exist.

Blastocyst material was obtained from 25 pigs during the period 10 to 33 days post coitum, and fixed thin sections of tissue were hybridized in situ to sense and antisense fos RNA probes synthesized using the expression vector Bluescribe M13+. Indirect immunofluorescence using antisera to a synthetic peptide fragment of c-fos was used to confirm the tissue distribution of oncogene-encoded proteins, which were shown by immunoprecipitation to have Mrs of 55 000 and 40 000, which are the known Mrs of the fos gene product and an associated nucleoprotein, respectively. Northern and slot blots were used to assess the distribution of c-fos mRNA and the size of the fos transcript was found to be 2·3kbases. C-fos was expressed in trophectoderm from blastocysts early in pregnancy but declined with increasing blastocyst development so that it was virtually absent by day 19 of gestation. High levels of fos proto-oncogene expression were, however, retained in the allantoic membranes up to at least day 19 of pregnancy. The expression of the fos protein could be prolonged in trophectodermal cells in monolayer culture by addition of conditioned medium from blastocysts cultured for 2 h, suggesting the presence of a growth-factor-like substance.

SUMMARY Plasma growth hormone (GH) levels were measured in 55 patients with advanced breast cancer, before and 3 months after pituitary ablation either by yttrium-90 implantation or by transethmoidal hypophysectomy. It was found that four of the 46 patients tested before ablation had an 'absent' GH response to insulin-induced hypoglycaemia. A comparison of the GH response to insulin-induced hypoglycaemia after yttrium implantation and transethmoidal hypophysectomy revealed no difference between the two procedures in the degree of pituitary ablation achieved. A partial GH deficiency occurred in 30% of patients after yttrium implantation but in only 4% after transethmoidal hypophysectomy.

Recording the gross outlines of breast tumours. A pathological assessment of the accuracy of radiographs of breast cancers

The question of which breast cancer patients to treat has been addressed by reviewing posters presented at the International Symposium on Endocrine Therapy. To date, tamoxifen therapy is the dominant type of adjuvant treatment in postmenopausal patients. The most promising results have been obtained in node-positive disease where the effect may be influenced by the receptor status, although this may depend on the cut-off level used.

Sequencing of the 40 N-terminal amino acids of the blastocyst protein responsible for blocking corpus luteum regression in early pregnancy in sheep revealed a 37% homology with human α-interferon; 28% of the remaining amino acid changes were conservative. 125I-Labelled human α-interferon bound to membrane receptors from sheep uteri with an approximate Kd of 4 × 10−11 M; binding was inhibited by unlabelled α-interferon or purified blastocyst antiluteolytic protein. The blastocyst antiluteolytic protein therefore closely resembles the interferon-α family of antiviral proteins.

In 1974 a project was initiated in which patients with apparently operable breast carcinoma underwent special investigations in an attempt to identify occult metastasis in bone and liver. One hundred and seventy-two patients have been followed for two years or more and their axillary node histological findings reviewed. From analysis of these patients the following conclusions may be drawn. Careful clinical assessment, especially measurement of the primary tumour and palpation of the axillary nodes, remains a fundamental guide to the likelihood of early recurrence. Histological confirmation of node metastases is as valuable as clinical assessment, but is not superior unless other features of node histology are considered. Micrometastases do not increase the probability of early recurrence except in comparison with a group whose nodes lack both metastases and other unfavourable features. The majority of special investigations do not have additional predictive value, though a bone scan is useful in the small number (less than 10%) in whom it is positive.

A retrospective analysis of two groups of patients, one surviving 16–20 years and the other dying within 10 years after diagnosis and treatment of primary breast cancer has been undertaken to determine whether there were particular clinical or histological features associated with long-term survival. The striking histological dijfference between the tumours of the two groups of patients was the prevalence of tumours of ‘special’ invasive types (cribriform, tubular, lobular and medullary) in the long-term survivors. M icro-invasive and non-invasive carcinomas were also more common in the survivors. The tumours of the surviving group which were not of a ‘special’ type more commonly had a better histological grade than those tumours of patients dying early from breast cancer. In the overall group elastosis was present in significantly more tumours of the survivors whereas tumour necrosis, vascular and lymphatic invasion were ail significantly more common in the short-term survival group. Although there was a significantly increased incidence of earlier stage tumours in the long-term survivors, the histological distinctions between the two groups were independent of the differences in clinical features.

Oestrogen receptor activity has been determined in the primary tumours from 243 patients with breast cancer and the subsequent clinical course of the disease has been followed for one to five years. Patients with oestrogen receptor-negative tumours had significantly shorter disease free intervals and survival times than those with receptor-positive tumours. Patients with large tumours, or with palpable axillary lymph nodes, or with histopathologically proven involvement of axillary lymph nodes also had a poorer prognosis than those with small tumours, impalpable nodes or histopathologically noninvaded nodes. The prognostic value of oestrogen receptor status was independent of these other three indices so that combination of receptor status and node status permitted definition of groups of patients with particularly good and particularly bad prognoses. The independence of these prognostic indices may relate to the possibility that whilst oestrogen receptor status is an index of the intrinsic biological behaviour of the tumour, nodal involvement and tumour size are more likely to reflect the chronological stage in the course of the disease at which the patient presents.

Four hundred and seventeen patients with operable breast cancer treated by simple mastectomy were randomly allocated to have node sampling or total axillary clearance. There was no significant difference in the incidence of node positivity. One hundred and thirty-five patients had node sampling and were randomized at the completion of this procedure to have axillary clearance or to have no further surgery. All node positive patients who went on to have a clearance had positive samples, confirming the accuracy of the sampling technique.