Biomedical subjects
Publications and source records attributed to W R Miller.
The requirement of immediate and abrupt quitting ("cold turkey") can be an obstacle to the acceptance and accomplishment of abstinence as a long-term outcome. Three alternative "warm turkey" routes to abstinence are discussed: (a) sobriety sampling, (b) tapering down, and (c) trial moderation. Clinical research evidence and case examples are provided in support of these alternative approaches.
Aromatase activity may be detected both in breast adipose tissue and breast cancer in levels similar to or greater than those in other peripheral tissues. Factors influencing such local biosynthesis have been sought. Of 247 primary breast cancers investigated, 178 showed evidence of oestrogen biosynthesis. No significant relationships were found between either the presence or levels of activity and tumour histopathology, patient characteristics (such as age and menopausal status), disease stage and prognosis (determined by disease-free interval and survival after primary treatment). Aromatase was more likely to be found in cellular cancers and those which were oestrogen receptor-positive, but these were not absolute associations, activity being detected in tumours with all degrees of cellularity and both receptor-positive and receptor-negative cancers. However, in a small group of patients with metastatic oestrogen receptor-positive tumours, response to the aromatase inhibitor, aminoglutethimide, seemed confined to tumours with aromatase activity. Oestrogen biosynthesis was detected in all specimens of breast adipose tissue examined. Activities were higher in fat from breast cancer patients compared with that from women with benign breast disease. In breasts with cancer, levels were higher in quadrants bearing tumour compared with those without evidence of malignancy. It is suggested that either enhanced aromatase in breast fat promotes the appearance of overt cancer or tumour factors induce aromatase in surrounding fat. Finally, although no significant correlations were detected in postmenopausal women between local aromatase activity and endogenous oestrogens in breast cancer, perfusion studies show that in situ oestrogen biosynthesis is primarily responsible for oestrogen levels in the majority of breast tissues. These data suggest that local aromatase activity may influence events within the breast and may be associated with the natural history and progression of certain malignancies.
Controversy exists as to whether interferons usefully influence the growth of epithelial carcinomas. A small cell lung carcinoma (SCLC) cell line, WX322, has been derived which is greater than 1000-fold more sensitive to alpha-interferon (IFN) when grown in agar than other reported SCLC cell lines. The WX322 line has been characterised to prove its epithelial origin and its chemosensitivity compared with that of the NCI-H69 small cell line. The WX322 cell line expresses neuroendocrine and epithelial markers and possesses a morphology consistent with SCLC origin. A concentration of 5 IU ml-1 of IFN produced 50% inhibition of colony formation in agar in the WX322 line, whereas a concentration of greater than 10(5) IU ml-1 was required to produce a comparable effect with the NCI-H69 cell line. In contrast, WX322, possessed similar sensitivity to NCI-H69 cells when exposed to a range of cytotoxic agents. Analysis of the cell cycle indicated that IFN increased the percentage of cells in the G0/G1 phase for the WX322 cell line but increased the percentage in S phase for the NCI-H69 line. Growth of the xenograft, from which the cell line was derived, was also inhibited by IFN at doses greater than 10(5) IU/mouse/day. The WX322 cell line whether grown in agar or as a xenograft shows an unusually high sensitivity to IFN and provides an interesting model for studying mechanisms of IFN cytotoxicity to epithelial cells.
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Cyclic AMP Binding Proteins (cAMP-BP) levels have been measured by means of a competitive binding assay in the cytosols of 50 human colorectal cancers. These levels have been related to those in mucosa both adjacent to and distant from the tumour in the same patients. Cyclic AMP-BP were higher in tumour than in either adjacent (P less than 0.000001) or distant mucosa (P less than 0.00001). Binding of cAMP in adjacent mucosa was lower than that in distant mucosa (P less than 0.0001). There was no significant difference in the level of binding between tumours arising from different sites in the colon and binding was not related to age or sex of the patient. However, binding was higher in Dukes' B than Dukes' C cancers (P less than 0.005). There was also a trend for cAMP binding levels to be higher in moderately differentiated than in poorly differentiated cancers (P = 0.07). Thus cAMP-BP appear to be over-expressed in human colorectal cancers and levels are related to the stage and grade.
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The biology of oestrogens as applied to the development and progression of breast cancer has been reviewed. Particular consideration has been given to: (i) the sources by which the breast and its tumours may be supplied with oestrogen; (ii) the patterns of endogenous oestrogens within the breast; (iii) the mechanisms by which oestrogens may exert their action; and (iv) the molecular events which follow oestrogen deprivation and which may lead to hormone independence. From a greater understanding of these fundamental processes, novel antioestrogenic measures are being developed which represent more acceptable endocrine treatments for patients with breast cancer and offer the hope of preventative medicine for individuals at high risk of the disease.
Simple calculation rules are providing for converting alcohol consumption data among four standard units currently used by researchers and educators in the USA, Canada, the UK, and Australia. A plea is made for the adoption of a common method for reporting alcohol consumption in research, using metric fluid volume units.
This study undertakes an analysis of cost effectiveness of alcoholism treatment modalities based upon (1) findings from clinical trials, (2) costs for treatment in settings and/or by providers and (3) recommendations from treatment experts about appropriate settings, providers and treatment events. This analysis, which assumes a prototypic patient, suggests that modalities with the most evidence of effectiveness (based on three or more clinical trials) are not the most expensive. Within this study, total cost of care was negatively related to effectiveness. Modalities categorized as having insufficient evidence of effectiveness (i.e., lacking three or more clinical trials) are in the higher cost categories. The results of this first effort to establish initial cost/effectiveness considerations are intended to stimulate researchers to conduct the types of clinical studies where both cost and effectiveness are carefully measured to increase the scientific basis for future cost/effect policy considerations. The authors expect future clinical studies will revise the results of this initial effort.
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Aromatase activity has been measured in human breast cancers by incubating tumour minces with [7 alpha-3H]testosterone and characterizing purified oestradiol (E2) fractions by chemical derivative formation. Of 247 primary tumours, 178 showed evidence of oestrogen biosynthesis, levels varying between 0.5 and 12.5 fmol E2 produced/h/g tissue. These values were quantitatively small but at least comparable with those in other peripheral tissues. There was no correlation between presence or level of aromatase activity and the histopathology of the tumours although oestrogen biosynthesis was more likely to be present in more cellular tumours. Aromatase activity was also unrelated to age, menopausal status, lymph node status and T stage of the patient from which the tumour was derived. In a subgroup of patients presenting without clinical evidence of distant metastatic disease, no significant relation was detected between tumour aromatase and disease-free interval, but tumours without aromatase activity were associated with increased survival at 36 months after primary treatment. A statistically significant correlation was also detected between the presence of tumour aromatase and oestrogen receptors. Furthermore, in small subgroups of patients with "advanced" breast cancer tumour aromatase was related to response to aminoglutethimide but not tamoxifen therapy. Whilst these results do not conclusively define a role for local synthesis of oestrogen in the progression of breast cancer, this possibility still exists and further studies on tumour aromatase are warranted.
Endocrine therapy is a major treatment modality for the systemic management of breast cancer. In comparison with alternatives such as chemotherapy, hormone manipulations have the advantage of lower toxicity but suffer from the disadvantages of producing responses in only 30-40% of patients with metastatic disease and seldom being curative. Nevertheless in recent years there have been significant advances in the endocrine treatment of breast cancer which have stemmed from a better understanding of the sources from which breast tumours may be supplied with hormones, the mechanism by which hormones regulate tumour proliferation and the more accurate identification of hormone sensitive tumours. As a result agents such as antioestrogens, aromatase inhibitors. LHRH agonists have largely superseded surgical and radiological ablation of endocrine organs. The major reduction in morbidity associated with these medical regimes means that they are much more acceptable to patients and may be used as adjuvants to local treatment of the breast in patients with "earlier" stages of the disease. At the same time patients can now be offered rational treatment selected on the basis of tumour biology rather than on more empirical criteria. The aims of this review are to provide details of the research which has led to this progress in endocrine treatment of breast cancer and to put into perspective the prospects for further advances.
Epidemiological and clinical evidence suggests that steroid hormones are intimately involved in the natural history of many cancers, including those of the breast, endometrium and prostate. However, it has been difficult to demonstrate that progressive changes in tumour development are related to circulating levels of steroids. This may be because further metabolism of steroids occurs locally within the tumour and its adjacent host tissue. Using the breast as an example, data has been reviewed that such local metabolism may (a) markedly change the biological potency of steroid hormones and (b) be associated with the risk, presence, pathology, stage and hormone sensitivity of cancer. The implications of these findings are discussed including the need to identify factors which regulate steroid metabolism in peripheral tissue and tumours. In this way the potential to influence the microenvironment around and within tumour cells may be realized in favour of the patient.
Human breast secretions, as obtained by nipple aspiration, were analysed for the presence of mutagenic activity by means of the Ames test. The overall incidence of women with secretions giving positive tests against Salmonella typhimurium, either strain TA98 or TA100, was 7.64%. No significant association was identified between the incidence of mutagen-positive breast secretions and age, menopausal status or the presence of breast abnormality in these women. Furthermore, there was no obvious environmental characteristic common to women with mutagen-positive fluids.
Plasma and cyst fluid were obtained from patients with palpable breast cysts and analysed for androgen conjugates and oestrone sulphate content by radioimmunoassay. Concentrations of androgen conjugates in cyst fluids varied from 15.6 to 475.5 mumols/l. These levels were much greater than those in plasma (1.3-5.2 mumols/l) and there was no association between values in cyst aspirates and plasmas obtained from the same individuals. Levels of oestrone sulphate in breast cyst fluids (1.5-744.0 nmol/l) were also generally in excess of those in plasma (2.0-59.9 nmol/l) and again no relationship was evident between concentrations in cyst fluid and the circulation. Neither was there a relationship between levels of androgen conjugate and oestrone sulphate in plasma. In contrast, a highly significant correlation (P less than 0.001) was identified between the androgen conjugate and oestrone sulphate content of cyst fluids. Levels of both androgen conjugates and oestrone sulphate were also significantly different in groups of cysts subdivided according to electrolyte classification, cysts with low Na+:K+ ratios having higher steroid concentrations than those with high Na+:K+ ratios. The biological significance of the relationship between the two conjugates in cyst fluids remains unclear but it is suggested that the accumulation of these steroids involves a common mechanism.
The release of a gross cystic disease fluid protein (GCDFP 15) by tumour explants grown in tissue culture was used to measure apocrine differentiation in 117 women with breast carcinoma. GCDFP 15 was detected by radioimmunoassay in the media from 90% of tumours (range 2-2100 ng/ml, mean 41). Tumour secretion of GCDFP 15 was higher in oestrogen receptor rich (over 20 fmol/mg) tumours (P less than 0.05) but did not correlate with any other prognostic factors or with survival. Response to hormonal therapy was assessable by UICC criteria in 33 women (6 partial responses, 8 stable disease, 19 progression). Responders had significantly higher tumour oestrogen receptor levels (P less than 0.005) but a lower GCDFP 15 secretion than non-responders (P less than 0.02). Apocrine differentiation in breast cancer may be a marker for oestrogen receptor positive tumours that do not respond to hormonal therapy.
p53 messenger RNA expression was examined using a cDNA probe in 76 fresh primary breast tumour specimens, 15 of which came from patients treated with toxoxifen prior to surgery. A 2.8 kb mRNA for p53 was expressed in 43 of the 76 specimens. In 19 tumours the levels were similar to those seen in non-malignant (reduction mammoplasty) breast tissue, but in 24 tumours over-expression of mRNA for p53, approaching that seen in three breast cancer cell lines, was found. The cell lines MCF-7, T-47D and MDA-MB-231 expressed three p53 mRNA species of about 2.8 kb and a forth of 1.6 kb. Increased mRNA expression for p53 correlated (P less than 0.05) with loss of genetic material from the short arm of chromosome 17 as demonstrated by allele loss with the VNTR probe YNZ 22.1. There was also statistically significant correlation between increased p53 mRNA expression and low oestrogen receptor protein content in the tumours (P less than 0.05), but not with other clinical parameters. The findings support the view that p53 is involved in breast tumour biology, and suggest that its role may be complex.
Apocrine differentiation in human breast cancers has been assessed using immunohistochemistry to detect zinc alpha 2 glycoprotein and the findings related to standard prognostic factors, disease free interval (DFI) and survival in 145 women with early breast cancer. Breast tumour samples from women with a minimum follow-up of 5 years were assessed. Routinely fixed and processed tissue was used throughout. Sixty-six (45%) tumours did not stain with the antibody. Fifty-two (36%) exhibited positive apocrine staining while for 27 (19%) only a few cells were reactive. The presence of apocrine differentiation was unrelated to lymph node status, menstrual status, tumour grade or size, oestrogen receptor (E2R) or progesterone receptor status. However, patients whose tumours exhibited apocrine staining had a shorter disease-free interval (DFI) (P = 0.03) and survival (P = 0.03). A Cox's multiple regression analysis of the data found that the presence of staining added significantly (P = 0.047) to the predictive value of node status (P = 0.0001), menstrual status (P = 0.0001), tumour size (P = 0.0026) and E2R status (P = 0.0014) for patient survival. The other seven prognostic factors tested did not reach significance and were rejected from the model. Apocrine differentiation in breast cancer appears to be an independent predictor of poor prognosis tumours.