The relationship between blood prolactin levels and risk of breast cancer in premenopausal women

Single specimens of blood have been taken from over 5000 normal volunteer women in each of two sequential (1967-1976, 1977-1984) population-based studied on the Island of Guernsey. Multivariate analysis was used to determine the relationship between prolactin levels and risk factors in breast cancer in 2591 and 1959 premenopausal women in whom blood prolactin had been measured. In both populations the prolactin concentrations appeared to be log-normally distributed and therefore all analyses have been done on log-transformed data. Initially the variables in the statistical model were age at menarche, ages at first and last baby, parity, ponderosity (Quetelet Index), mammographic pattern (as graded by Wolfe), family history of breast cancer, age, menstrual cycle status, time of day of blood sampling, oral contraceptive use, history of breast feeding and methodological changes in the laboratory measurement of prolactin. Of these variables age at menarche, ages at first and last child and family history of breast cancer were found not to be significant and were excluded from the final model. The main finding to emerge was that after standardizing for all the other variables, prolactin levels in the follicular phase were significantly lower than those found at midcycle or during the luteal phase of the menstrual cycle. A peak level of prolactin was found at day 12 of the cycle. Increasing parity was related to a steady decrease in prolactin concentration. Increasing ponderosity was associated with an increased prolactin level as was a DY compared to an N1 mammographic pattern. Women with a history of oral contraceptive use had lowered prolactin concentration. All these effects occurred evenly over the menstrual cycle and were generally found for both data sets. Thus body weight, parity and, indirectly, age at first baby might influence breast cancer risk by being associated with changes in blood prolactin concentration.

Sex-hormone-binding globulin and breast cancer risk

We have measured serum concentrations of SHBG in 5000 women over the age of 35. In both premenopausal and postmenopausal women who were not suffering from cancer or other diseases or taking drugs likely to affect SHBG, the protein decreased with increasing weight and was lower in single nulliparous women than in married nulliparous women or parous women. In premenopausal women, SHBG was higher in women with late menarche. These findings suggest that diminished SHBG concentrations may be associated with the increased risk for breast cancer conferred by nulliparity and early menarche.

Ovarian function and adjuvant chemotherapy for early breast cancer

The effect of cyclophosphamide, methotrexate and fluorouracil (CMF) on ovarian function has been studied in 74 pre-menopausal patients with operable breast cancer. After median follow-up of 47 months, 50, 70 and 80% of 35 patients receiving CMF became permanently amenorrhoeic within 3, 6 and 12 months respectively; in contrast, only 5 in the no treatment (control) group of 39 patients became permanently amenorrhoeic within 12 months. Younger patients (less than 35 years) were more likely to retain or regain menstrual function while on or after CMF treatment. Estimation of ovarian and pituitary hormones in a subset of these women showed that CMF treatment was associated with a decrease in serum oestradiol and progesterone and an increase in serum follicle stimulating hormone and luteinizing hormone to post-menopausal levels. These hormonal changes are consistent with the induction of amenorrhoea during CMF treatment and the absence of resumption of menstrual function after completion of treatment suggests that CMF causes permanent ovarian ablation in a majority of these patients.

Binding of oestradiol to blood proteins and aetiology of breast cancer

A prospective study of 5,000 women has shown that, compared to controls, those who subsequently developed breast cancer had a higher proportion of their blood oestradiol in the non-protein-bound and albumin-bound fractions (the bio-available fraction) and a lower proportion in the sex-hormone-bound fraction. The increased proportion of bio-available oestradiol was partly due to a lower concentration of sex-hormone-binding globulin. Weight was excluded as a confounding factor.

A prospective study of mammographic parenchymal patterns and risk of breast cancer

Breast parenchymal patterns have been assessed by the method of Wolfe in a prospective study in Guernsey. Women with P2 or DY grades had approximately four times the risk of developing breast cancer compared with those with N1 or P1 grades. Age, weight, parity and age at birth of first child are all related to the distribution of mammographic patterns. The combination of these variables with Wolfe grades may identify subsets of the population at very high risk.

Salivary oestradiol and progesterone levels in premenopausal women with breast cancer

The concentrations of oestradiol and progesterone have been measured in salivary specimens collected daily over a complete menstrual cycle in 12 patients with operable breast cancer and 12 normal control volunteers. There was no significant difference (P greater than 0.05) for either hormone between these two groups. Both showed a mid-cycle rise in oestradiol levels followed by a smaller but sustained increase during the luteal phase. The progesterone concentration increased markedly during the luteal phase of the cycle. Total or non-protein bound oestradiol levels measured in blood samples from 19 normal women were both linearly correlated (P less than 0.001) with the concentration of oestradiol in matched saliva samples. The amount of free oestradiol in blood was about twice that found in saliva.

Serum prolactin levels in women with breast cancer and their relationship to survival

Serum prolactin (HPr) has been measured in 459 patients 1 day before (HPr-1) and in 433 patients 10 days after (HPr-2) treatment. These came from an unselected sequence of 739 patients with operable breast cancer who had been referred to Guy's Hospital over a period of 5 yr. In addition HPr was measured in 100, or more, women at 3, 6 or 12 months after mastectomy. The median levels of either HPr-1 or HPr-2 were higher in pre-menopausal compared with postmenopausal patients (P = 0.03 and 0.06, respectively). Mastectomy was associated with increased serum HPr in both pre- and post-menopausal patients (P less than 0.001 in both cases). Average levels at 3 months, or after, were similar to those found before treatment. Nulliparous women had a higher median amount of HPr-1 than parous which was significant in premenopausal patients (P less than 0.008) whilst HPr-2 levels were not related to parity. Thus the rise in HPr associated with surgery was greater in parous than nulliparous women. Prolactin levels were not related to nodal status or tumour size. However, the amounts of HPR-2 were significantly greater in women with histological grade 3 tumours than those with grade 1 or 2. Standardising for either nodal status, tumour size or histological grade seven situations were found in which HPr-1 or HPr-2 levels were of prognostic significance. Although some of these significant associations could be fortuitous all shared a common feature that the least favourable prognosis was associated with the highest HPr levels.

The prevention of breast cancer

The case for treating women at high risk of breast cancer with the anti-oestrogen tamoxifen is presented. This is a logical extension of a screening programme and is scientifically based on the effectiveness of tamoxifen in established disease, the relation between free oestradiol (and other hormone-related factors) to the risk of breast cancer, and the lack of side-effects from tamoxifen treatment. Choice of a high-risk group is critical; a specific trial protocol is outlined.

Diurnal variations in prolactin and growth hormone levels in normal premenopausal vegetarian and omnivorous women

Diurnal levels of plasma prolactin and growth hormone were measured in 47 normal premenopausal women, 26 of whom were established vegetarians and 21 of whom were omnivorous controls. There were no differences between the median prolactin levels of the two groups during a 24-hour period of investigation. When the groups were further subdivided into ovolactovegetarians and vegans, still no differences were found in prolactin secretion. In contrast, the vegetarian women exhibited elevation of growth hormone levels during the period of study, which was particularly marked at midnight and 10 A.M.

A comparison of results of type I and type II radical operations for carcinoma of the gastric cardia

During 1954-1981, 527 patients with cancer of the gastric cardia underwent resection. Of these, 146 underwent type I radical operation (transthoracic resection) with eight (5.5%) operative deaths; 344 underwent type II radical operation (abdominothoracic resection) with 42(12.2%) operative deaths; and 37 with Stage IV lesions underwent extended operation or palliative operation with 4(10.8%) operative deaths. Of 440 cases of Stage I-III cases that survived the operation, the 5-year survival rate was 18.5%, and the 10-year survival rate was 10.7%. For stage I cancer, the end results of type I and type II radical operations were similar. In Stage II, whether the lymph nodes were positive or negative, the end result of the type II operation was better, but without statistical significance. In Stage III cancer without lymph node metastases, the end result of the type II operation was better, but without statistical significance; in those with lymph node metastases, the type II operation was definitely better than the type I operation (P less than 0.05).

Salivary progesterone: relation to total and non-protein-bound blood levels

The daily amounts of salivary progesterone have been determined over the complete menstrual cycle for 9 normal women. The level of progesterone during the follicular phase was about 150 pmol/l and increased significantly to about 350 pmol/l during the luteal phase of the menstrual cycle. The amounts of salivary progesterone were significantly correlated with those in blood (P less than 0.001) in paired saliva-blood specimens taken from 96 women. Although these volunteers comprised patients with benign and malignant breast disease and normal unaffected women, the relationship between salivary and blood progesterone was similar for all groups. The concentration of non-protein-bound progesterone was determined using equilibrium dialysis. To correct for serum dilution the linear relationship between the percentage of progesterone bound and the reciprocal of serum dilution has been exploited. The values of non-protein-bound progesterone obtained were significantly and linearly correlated with levels in saliva (r = 0.75, P less than 0.001, d.f. = 34) although the amount of free progesterone in blood was about five times that found in saliva.

Influence of reproductive history on age at diagnosis of breast cancer and prognosis

The effect on age at breast cancer diagnosis of age at menarche, age at first baby, parity and age at menopause has been determined for 739 unselected patients diagnosed between 1975 and 1980 as having operable breast cancer. Age at diagnosis was significantly and positively associated with ages at menarche, first baby and menopause. The average number of children significantly declined with increasing age at diagnosis. This was largely due to a change in the proportion of patients who were nulliparous (15% in women aged 41-50 years compared to about 30% in those over 60 years). A group of 1,989 normal women whose reproductive history was also collected between 1975 and 1980 showed similar trends between age and age at menarche, age at first baby and parity as the patients. Thus it appears that these reproductive parameters do not alter the time of onset of breast cancer but could be explained by temporal changes in reproductive patterns. There was no significant correlation between age at menopause and age at diagnosis for patients whose age at menopause was no more than 54 years and age at diagnosis no less than 55 years, respectively. It is therefore unlikely that age at menopause affects age at diagnosis. Postmenopausal patients with 3 or more children had a significantly shorter disease-free interval and lower survival rate than those with less children. None of the other parameters was associated with prognosis.

A solid-phase radioimmunoassay of serum dehydroepiandrosterone sulphate using a monoclonal antibody

A monoclonal antibody directed against dehydroepiandrosterone, but with high affinity for dehydroepiandrosterone sulphate (DHA-S), has been used to develop a solid phase radioimmunoassay for measuring serum DHA-S. The antibody was covalently linked to polyacrylamide microbeads with no change in binding characteristics. The procedure requires only the chromatography of serum on anion-exchange cellulose before assaying the equivalent of 0.25 microliter serum. The method is precise, accurate and specific and can detect 19.5 pg of DHA-S. Serum DHA-S levels measured by this method were in good agreement with those found in a validated radioimmunoassay method involving hydrolysis. The method is quick and one operator could assay 50 blood specimens per day. DHA-S levels in serum from 50 men and 86 women were in agreement with those in the literature. With the availability of theoretically limitless quantities of consistently high quality monoclonal antibodies the advantages of developing solid phase radioimmunoassays for steroids is discussed.

Effect of prednisolone on hormone profiles during primary endocrine treatment of advanced breast cancer

Various plasma hormones were measured in 13 pre- and 20 post-menopausal women with advanced breast cancer before and for 12 months after ovarian irradiation or during continuous administration of tamoxifen at a dose of 10 mg twice a day, respectively; some patients received additional prednisolone at a dose of 5 mg twice a day. These patients were taken from a larger clinical trial which demonstrated a higher response to primary endocrine therapy when prednisolone was added. Levels of dehydropiandrosterone sulfate were depressed in patients receiving prednisolone, confirming adrenal suppression. Estradiol levels were reduced in all patients, while luteinizing hormone and follicular stimulating hormone increased after ovarian irradiation, but all three hormones fell during tamoxifen administration; no further changes were caused by the addition of prednisolone. Prolactin and thyroxine remained constant throughout the study. There were no differences between responders and nonresponders in hormone profiles or in changes in the profiles after treatment.

Serum progesterone concentration during the luteal phase in women with benign breast disease

Earlier studies of the serum concentration of progesterone during the luteal phase in women with benign breast disease have produced conflicting results. Serum progesterone profiles were therefore measured in relation to cyclical breast pain and in biopsied benign disease. No evidence of progesterone deficiency was found.

Somatic embryogenesis and plant regeneration in cultured immature inflorescences of Setaria italica

Young inflorescence explants of Setaria italica in culture showed high capacity for regenerating plantlets through somatic embryogenesis. Embryogenic callus formation was initiated from the explants cultured on Murashige and Skoog's medium with 2 mg/l 2,4-D and 0.2-0.5 mg/l KT or BAP, but it was better for the maintenance of embryogenic growth to subculture the calli on the medium with 2,4-D and KT/BAP and on the medium with 2 mg/l 2iPA and 0.2 mg/l NAA alternately. A number of plantlets were regenerated when embryogenic calli were transferred onto the same basic medium but with 2 mg/l BAP and 0.5 mg/l NAA. Plant regeneration capacity has been maintained in some embryogenic calli during fourteen months of subculture.

Somatic embryogenesis inEchinochloa crusgalli

A white, compact embryogenic tissue was obtained from young inflorescence segments ofEchinochloa crusgalli (barnyard grass) cultured on Murashige and Skoog's medium containing various concentrations and combinations of 2,4-dichlorophenoxyacetic acid and 6-benzylaminopurine. Histological and scanning electron microscopic studies revealed that the white compact callus contained embryoids in various stages of development. Typical embryoids were bipolar and possessed scutella, coleoptiles and coleorhizae. The embryogenic nature of the callus was maintained throughout eight to ten subcultures spanning more than six months. A high frequency of plant regeneration was obtained when the 2,4-D concentration was reduced or 2,4-D was removed from the medium.

Nyctohemeral changes in plasma prolactin levels and their relationship to breast cancer risk

The amount of prolactin has been determined in serial blood samples taken over 24 h from 20 pre- and 9 postmenopausal women volunteers. All women had a large increase in prolactin at night (24.00 h-03.00 h). A much smaller rise in prolactin occurred in the evening (18.00 h-20.00 h) which was just significantly different (p less than 0.05) from levels found in the afternoon. Prolactin concentrations at any given time in the 29 women were linearly correlated with corresponding levels in either of the adjacent time intervals. This correlation was highly significant (p less than 0.001) throughout 24 h, implying that a woman with a relatively high (or low) blood prolactin in the afternoon would have a similarly high (or low) concentration in the evening or at night. Premenopausal women had higher amounts of prolactin than postmenopausal volunteers throughout the day. Parity was found to be inversely related to prolactin levels in pre- and postmenopausal women; this effect was especially marked in the night peak of prolactin. In postmenopausal women an average of 33 years had elapsed since the birth of the last child, which implies that childbirth has a life-long effect on reducing prolactin levels. Thus the protective effect of early child-bearing and multiparity against developing breast cancer could be at least partly explained by these effects on serum prolactin levels.

Simultaneous production of monoclonal antibodies to dehydroepiandrosterone, oestradiol, progesterone and testosterone

Mice were immunized with a mixture of four steroid antigens: dehydroepiandrosterone (DHA), oestradiol, progesterone and testosterone linked to bovine serum albumin through the 7, 6, 11 alpha and 17 beta positions respectively. The response to immunization varied widely with no one mouse producing an optimal response to all four steroids. In the two fusion experiments performed, antibodies to all four antigens were developed. Data are presented which show that the immune response of the spleen donor is related to the relative numbers and quality of the antibodies produced to each steroid. Despite the structural identity of the progesterone and testosterone haptens, antibodies elicited in response to their respective antigens could readily be distinguished from each other. From the large number of monoclonal antibodies obtained those most useful for radioimmunoassay were three high affinity antibodies to oestradiol and two antibodies raised against DHA but with high affinity for DHA sulphate.

Nuclear pore complex in spermatogenesis of Beijing domestic duck. Electron microscope observation of freeze-etching

The nuclear pore complex in spermatogenesis of Beijing domestic duck has been studied by means of electron microscopic observation of freeze-etching. The structure of the pore observed proves to be in accord with the model of the nuclear pore complex proposed respectively by Franke (1970) and Roberts et al. (1970). But its central granule may be present (1-3 granules) or absent. The granules are considered to be material in transit. The size and frequency of the pore vary with different types of reproductive cells, which is believed to be related to the cells' function. The pores concentrate on the side of nucleus near Golgi zone in primary spermatocyte and near the proacrosome of spermatid, and this shows the functional variety of parts in the nucleus.

Urinary hydroxyproline and prognosis in human breast cancer

The excretion of urinary hydroxyproline has been measured before mastectomy in 342 patients presenting with breast cancer for the first time to Guy's Hospital. The first 106 women were maintained on a gelatine-free diet whilst the remainder were on unrestricted diet. In both dietary groups hydroxyproline levels or the ratio of hydroxyproline to urinary creatinine were not related to pathological stage or histological grade. The time between initial presentation and subsequent bone metastases was negatively and significantly associated with hydroxyproline excretion (P less than 0.05) and the ratio of hydroxyproline to creatinine (P less than 0.01) in women on a gelatine-free diet. A similar, but not significant, trend was observed in patients on unrestricted diet. Although hydroxyproline excretion was related to the time to onset of bone metastases the amount of hydroxyproline excreted by these patients was not significantly different from patients who had recurrences at sites other than bone or patients who were disease-free up to 5 years after initial diagnosis. The conclusion is that hydroxyproline is of little value in the early detection of bone metastases.

Serum carcinoembryonic antigen in the diagnosis and prognosis of women with breast cancer

Serum carcinoembryonic antigen (CEA) has been measured in 628 patients before and 577 patients after treatment for breast cancer. These came from an unselected sequence of 730 women, subsequently diagnosed as having stage I or II breast cancer, referred to Guy's Hospital over a period of nearly 5 yr. CEA was also measured in serum from 238 ostensibly healthy volunteers and 65 women with benign breast disease. CEA measurements were of no diagnostic value. There were more patients with breast cancer with values in excess of 10 ng/ml measured preoperatively (7%) or after mastectomy (5%) than in controls (3%), but the difference is of marginal significance. High levels of CEA were not consistently associated with pathological stage or histological grade. Mastectomy was not associated with any significant change in the distribution of CEA levels. Patients with stage II disease and pre-operative CEA levels over 10 ng/ml has a faster recurrence rate than those with levels of less than 2.5 ng/ml. High levels were also associated with reduced survival. However, such patients comprised about 5% of women presenting with early breast cancer, so that the use of CEA measurements for prognosis is of limited value.

Characterisation of monoclonal antibodies raised against testosterone

Using the antigens testosterone-17 beta-hemisuccinate and testosterone-3-(o-carboxymethyl) oxime, each coupled to bovine serum albumin, we have produced 44 monoclonal antibodies to testosterone. Of the 17 monoclonal antibodies raised against the 17 beta-linked antigen 8 showed extremely low affinity for testosterone (Ka less than or equal to 8 X 10(7) M-1) and none had an affinity greater than 5 X 10(9) M-1. Of the 27 monoclonal antibodies raised against the 3-linked antigen 2 had affinities less than 8 X 10(7) M, 7 had affinities greater than 5 X 10(9) M-1 and one had an affinity (Ka = 9 X 10(10) M-1) greater than that of a high affinity rabbit antiserum (Ka = 6 X 10(10) M-1). The affinity constant (Ka = 5 X 10(9) M-1) measured in the serum of the mouse whose spleen gave rise to the greatest number of high affinity antibodies, was significantly higher than those measured in the sera of the remaining mice (Ka = 0.7 - 3 X 10(8) M-1). The cross-reactions of the monoclonal antibodies varied widely but none showed an overall improvement in specificity when compared with the corresponding rabbit antisera. Results suggest that as well as the structure of the steroid antigen careful selection of the spleen donor facilitates the development of monoclonal antibodies with good binding characteristics.

Breast parenchymal patterns in women with bilateral primary breast cancer

Mammograms were obtained from 44 women aged over 30 years with bilateral primary breast cancer, 60 women with unilateral breast cancer, matched for age and menopausal status with the bilateral cases, and 937 normal women, again all aged over 30 years. The mammograms were classified according to Wolfe's criteria. Both groups of cancer patients were found to have a significantly (p less than 0.05) greater proportion of pre-menopausal women with the DY type of breast parenchymal pattern compared with the normal pre-menopausal women. No association was found between the P2 mammographic pattern and breast cancer. The study failed to show any difference in the distribution of mammographic risk categories in women with bilateral disease and those with unilateral cancers only.

The production of high affinity monoclonal antibodies to progesterone

Using different immunisation regimens and the antigens 6 beta-hydroxyprogesterone hemisuccinate and 11 alpha-hydroxyprogesterone hemisuccinate conjugated to bovine serum albumin, we have produced 35 monoclonal antibodies against progesterone with a wide range of specificities and affinities (Ka = 8 x 10(7)-3 x 10(10) M-1). The 10 antibodies raised against the 6 beta-antigen showed no advantage in terms of specificity when compared with those raised against the 11 alpha-antigen. The four antibodies with the best binding characteristics were all derived from fusion experiments performed after long (5 booster injections) immunisation with the 11 alpha-antigen. Although the specificities of these monoclonal antibodies were similar to those of a high affinity rabbit antiserum raised against the same antigen, a measurable improvement in sensitivity was obtained when one of these four antibodies was used for radioimmunoassay.

The relation between radiological patterns of the breast and body weight and height

Mammograms were obtained from 942 normal volunteer women aged over 35 years, and were classified by Wolfe's criteria. There was no relationship between height and mammographic pattern. An increase in weight, whether corrected for height or not, was associated with an increase in the proportion of N grades and a concomitant decrease in DY grade mammograms. This effect reached formal significance in pre-menopausal women but was highly significant in post-menopausal women. For women who were either above or below their ideal weight there was a significant positive correlation between parity and the proportion of N and P1 mammograms. The slopes of the linear regression for these two groups were the same, although the elevation of the above-ideal weight group was significantly greater. This implies that for any given parity, there are about 16% more N or P1 grades in the above-ideal compared with the below-ideal weight group.

A prospective study of plasma prolactin levels and subsequent risk of breast cancer

Plasma prolactin was measured in 2,572 pre-menopausal, 628 menopausal, and 1,666 peri- and post-menopausal women who were apparently healthy. Breast cancer was subsequently diagnosed in 47 of these women at a median time of 5 years after blood collection (pre-cancer cases). Prolactin levels in pre-menopausal cases increased significantly with age whereas this was not found in matched controls. The perimenopausal cases were characterized by extreme variability in prolactin levels. In post-menopausal women who developed breast cancer, the prolactin levels were significantly elevated, being at or above the 70th percentile for the controls. In this group the results are consistent with prolactin acting as a late-stage tumour promoter.

Plasma prolactin levels and breast cancer: relation to parity, weight and height, and age at first birth

Plasma prolactin has been measured in over 3,500 women volunteers from a normal population. In premenopausal women there was a significant decrease in prolactin levels with increasing parity. However, this effect was transitory since plasma prolactin concentration rose with increasing time after the birth of the last child. There were no significant differences in prolactin levels with respect to height and weight, although overweight compared to underweight women had approximately 15% more plasma prolactin. If prolactin is a carcinogen, then these results are in keeping with the epidemiological findings that multiparity affords protection and that age at last delivery is a risk factor in the development of breast cancer.

The relation between radiographic features and determinants of risk of breast cancer

Mammograms were obtained from 942 normal women aged over 30 years, and were classified by Wolfe's criteria. In women with an enhanced risk of breast cancer associated with a late age at first child or nulliparity, there was a significant increase in the proportion of P2 and DY mammographic patterns which are thought to be a radiological index of risk. There was a decrease in the proportion of P2 and DY grades in women using steroidal contraceptives. However, the association between radiological and epidemiological determinants of risk did not hold for age at menarche.