Effects of parasitism and pesticide exposure on characteristics and functions of hemocyte populations in the freshwater snail Lymnaea palustris (Gastropoda, Pulmonata)

Morphological characteristics and functions of hemocytes were used to compare the immunological effects of biological and chemical stress in the freshwater snail Lymnaea palustris. Animals were either infected by a trematode parasite (Metaleptocephalus sp.), or exposed to environmental contaminants, namely atrazine and hexachlorobenzene (HCB). Three populations of circulating hemocytes, morphologically and cytochemically distinct (round cells, hyalinocytes, granulocytes), were identified in both control and parasitized or pesticide-exposed snails. After 6 h of exposure, HCB and atrazine resulted in 8-fold increases in the mean total number of hemocytes, whereas only a 2.2-fold increase was observed 6 h after cercaria emission in parasitized snails. The impact of HCB was limited to the first 24 h of exposure, whereas long-lasting effects of atrazine were observed. Hyalinocytes and, to a lesser extent, round cells contributed most to the increases in hemocyte density in pesticide-exposed snails. Parasitism and atrazine treatment resulted in significant increases of lectin-stained hemocytes, whereas exposure to HCB did not affect the percentages of stained and unstained cells. Hemocyte phagocytic activity increased in HCB-exposed snails but with no concomitant change of the oxidative burst. Opposite results were obtained in atrazine-treated snail hemocytes, with unchanged phagocytosis and decreased phorbol 12-myristate 13-acetate-stimulated production of reactive oxygen intermediates. No increase in phagocytosis, or in the production of reactive oxygen intermediates, was observed in hemocytes from parasitized snails. Infection with the immunologically compatible trematode parasite Metaleptocephalus sp. and exposure to atrazine generated similar reactions from circulating hemocytes, whereas a different response pattern was observed in HCB-exposed snails.

Haemocyte changes in resistant and susceptible strains of D. melanogaster caused by virulent and avirulent strains of the parasitic wasp Leptopilina boulardi

Two strains of Drosophila melanogaster (resistant and susceptible) were parasitized by a virulent or avirulent strain of the parasitoid wasp Leptopilina boulardi. The success of encapsulation depends on both the genetic status of the host strain and the genetic status of the parasitoid strain: the immune cellular reaction (capsule) is observed only with the resistant strain-avirulent strain combination. The total numbers of host haemocytes increased in all 4 combinations, suggesting that an immune reaction was triggered in all hosts. Resistant host larvae infected with the virulent or avirulent strains of parasitoid wasp had slightly more haemocytes per mm(3) than did susceptible host larvae at the beginning of the reaction (less than 15 h post-parasitization). This difference disappeared later. Only the virulent parasitoid strain caused the production of a high percentage of altered lamellocytes (from a discoid shape to a bipolar shape), half the total number of lamellocytes are altered. This suggests that the alteration of lamellocyte shape alone is not sufficient to explain the lack of capsule formation seen in resistant hosts parasitized by the virulent strain. Lastly, there were very few altered lamellocytes in resistant or susceptible hosts parasitized by the avirulent parasitoid strain, two combinations in which no capsule was formed. As is now established for Drosophila-parasitoid interactions, virus-like particles contained in the long gland of the female wasp affect the morphology of the lamellocytes. The results presented here are further proof of the action (direct or indirect) of virus like particles of the virulent strain on lamellocytes.

Cancer risk related to mammary gland structure and development

The breast undergoes dramatic changes in size, shape, and function in association with growth, reproduction, and post-menopausal regression. Those changes impact women's lifetime breast cancer risk. An early first full-term pregnancy exerts a protective effect, emphasizing the need for understanding the role of reproductive influences on breast development and on cancer initiation and progression, and providing a paradigm for developing preventive strategies based on physiological principles. Even though the cause of breast cancer and the ultimate mechanisms through which an early pregnancy protects from cancer development remain largely unknown, a likely explanation for this protection has been provided by experimental in vivo and in vitro models. These studies have led to the conclusions that cancer initiation requires the interaction of a carcinogen with an undifferentiated and highly proliferating mammary epithelium, whereas differentiation of the mammary gland inhibits carcinogenic initiation. The process of mammary gland differentiation is the result of complex interactions of ovarian, pituitary, and placental hormones, which in turn induce inhibition of cell proliferation, downregulation of estrogen and progesterone receptors, activation of specific genes, such as inhibin, mammary derived growth factor inhibitor and a serpin-like gene, and expression of extracellular matrix proteins in the normal breast. Cell immortalization and transformation are associated with the expression of ferritin H and S100P protein, which serve as markers of cancer initiation. Comparative studies of normal and neoplastic breast development have unraveled similarities with experimental models that validate the extrapolation of findings for testing hypotheses on the initiation and progression of breast cancer.

Mental illness, functional impairment, and patient preferences for collaborative care in an uninsured, primary care population

OBJECTIVE

Our goal was to compare the prevalence of mental illness and its impact on functional status in an indigent uninsured primary care population with a general primary care sample. We also hoped to assess patient preferences about mental health and medical service integration.

STUDY DESIGN

We compared a survey of consecutive primary care adults in April and May 1999 with a 1997-98 survey of 3000 general population primary care patients. Both studies used the Primary Care Evaluation of Mental Disorders Patient Health Questionnaire and the 20-question Medical Outcomes Study Short Form.

POPULATION

The patients were from a private nonprofit primary care clinic in Grand Junction, Colorado, that served only low-income uninsured people. We approached a total of 589 consecutive patients and enrolled 500 of them.

MAIN OUTCOME MEASURE

The main outcomes were the prevalence of psychiatric illnesses and the relationship with functional impairment. We compared our findings with a more generalizable primary care population.

RESULTS

This low-income uninsured population had a higher prevalence of 1 or more psychiatric disorders (51% vs 28%): mood disorders (33% vs 16%), anxiety disorders (36% vs 11%), probable alcohol abuse (17% vs 7%), and eating disorders (10% vs 7%). Having psychiatric disorders was associated with lower functional status and more disability days compared with not having mental illness. Patients indicated a preference for mental health providers and medical providers to communicate about their care.

CONCLUSIONS

This low-income uninsured primary care population has an extremely high prevalence of mental disorders with impaired function. It may be important in low-income primary care settings to include collaborative care designs to effectively treat common mental disorders, improve functional status, and enhance patient self-care.

The pathway of neoplastic transformation of human breast epithelial cells

The morphological analysis of breast cancer development indicates this to be a multistep process that progressively evolves from ductal hyperplasia and atypical ductal hyperplasia, which represent the initial stages of neoplastic growth, to carcinoma in situ, invasive carcinoma, and ultimately metastasis, as has been documented for a number of other malignancies. The understanding of the cellular and molecular processes that lead a normal cell to malignancy requires the analysis of pure populations of human breast epithelial cells (HBEC) representing specific stages of neoplastic progression. The neoplastic transformation of HBEC in vitro represents a successful model for obtaining knowledge about the molecular and biological alterations that may contribute to the tumorigenic mechanisms. We present here a current understanding of chemically transformed HBEC in the following aspects: (1) factors affecting the transformation of HBEC such as immortalization; (2) new targets for studying the mechanism of cell immortalization such as alterations in telomerase activity, differential expression of cell cycle-dependent genes, and others recently isolated through differential cloning, such as H-ferritin, and a calcium binding protein; (3) genetic mechanisms underlying cell transformation; and (4) application of the microcell-mediated chromosome transfer technique as an approach to testing the functional role of specific genes whose dysregulation or loss of function may contribute to the ultimate cell transformation. Further efforts in this cell system will be directed to determining the roles of identified molecular changes as well as the mapping/cloning of tumor suppressor or senescence genes.

RNA relocation and persistence of nucleolus-like bodies at mitosis in benzo[a]pyrene-transformed human breast epithelial cells after microcell-mediated transfer of chromosomes 11 and 17

RNA relocation and the incidence of nucleolus-like bodies accumulated during mitosis were studied cytochemically in benzo[a]pyrene (BP)-transformed human breast epithelial MCF-10F cells after microcell-mediated transfer of normal chromosomes 11 and 17. The changes resulting from the transfer of these two chromosomes in tumorigenic MCF-10F cells (BP1-E cell line) were examined, since alterations in these chromosomes are involved in the expression of the transformed and tumorigenic phenotypes in the MCF-10F cell series. In addition, the frequency of nucleolus-like bodies decreases drastically with transformation and tumorigenicity in MCF-10F cells, thus being conceivable that it would be affected in presence of normal chromosomes 11 or 17. The pattern of RNA relocation associated with the mitotic spindle did not vary in the cell lines analyzed. The introduction of chromosome 17 in BP1-E cells either decreased or did not affect the frequency of persistent nucleolus-like bodies. In contrast, in cells which received a normal chromosome 11, the frequency of nucleolus-like bodies was closer to that of non-transformed MCF-10F cells. These results suggest that a normal chromosome 11 but not chromosome 17 contributes to the maintenance of an RNA surplus which accumulates in nucleolus-like bodies during cell division of the human breast epithelial cells, at least in vitro. Some loci which were retained in the BP1-E cells which received a normal chromosome 11 are probably involved with the control of RNA transcript production. Figure 1 on http://www.esacp.org/acp/2001/23-3,4/mello.htm

Carcinogenicity of estrogens in human breast epithelial cells

Epidemiological and clinical evidences indicate that breast cancer risk is associated with prolonged ovarian function that results in elevated circulating levels of steroid hormones. Principal among these is estrogen, which is associated with two important risk factors, early onset of menarche and late menopause. However, up to now there is no direct experimental evidence that estrogens are responsible of the initiation of human breast cancer. We postulate that if estrogens are causative agents of this disease, they should elicit in human breast epithelial cells (HBEC) genomic alterations similar to those exhibited by human breast cancers, such as DNA amplification and loss of genetic material representing tumor suppressor genes. These effects could result from binding of the hormone to its nuclear receptors (ER) or from its metabolic activation to reactive metabolites. This hypothesis was tested by treating with the natural estrogen 17beta-estradiol (E2) and the synthetic steroid diethylstilbestrol (DES) MCF-10F cells, a HBEC line that is negative for ER. Cells treated with the chemical carcinogen benzo (a) pyrene (BP) served as a positive control of cell transformation. BP-, E2-, and DES-treated MCF-10F cells showed increases in survival efficiency and colony efficiency in agar methocel, and loss of ductulogenic capacity in collagen gel. The largest colonies were formed by BP-treated cells, becoming progressively smaller in DES- and E2-treated cells. The loss of ductulogenic capacity was maximal in BP-, and less prominent in E2- and DES-treated cells. Genomic analysis revealed that E2- and DES-treated cells exhibited loss of heterozygosity in chromosomes 3 and 11, at 3p21, 3p21-21.2, 3p21.1-14.2, and 3p14.2 14.1, and at 11q23.3 and 11q23.1-25 regions, respectively. It is noteworthy that these loci are also affected in breast lesions, such as ductal hyperplasia, carcinoma in situ, and invasive carcinoma. Our data are the first ones to demonstrate that estrogens induce in HBEC phenotypic changes indicative of cell transformation and that those changes are associated with significant genomic alterations that might unravel new pathways in the initiation of breast cancer.

Predictors of outcome in a primary care depression trial

OBJECTIVE

Previous treatment trials have found that approximately one third of depressed patients have persistent symptoms. We examined whether depression severity, comorbid psychiatric illness, and personality factors might play a role in this lack of response.

DESIGN

Randomized trial of a stepped collaborative care intervention versus usual care.

SETTING

HMO in Seattle, Wash.

PATIENTS

Patients with major depression were stratified into severe (N = 149) and mild to moderate depression (N = 79) groups prior to randomization.

INTERVENTIONS

A multifaceted intervention targeting patient, physician, and process of care, using collaborative management by a psychiatrist and primary care physician.

MEASUREMENTS AND MAIN RESULTS

Patients with more severe depression had a higher risk for panic disorder (odds ratio [OR], 5.8), loneliness (OR, 2.6), and childhood emotional abuse (OR, 2.1). Among those with less severe depression, intervention patients showed significantly improved depression outcomes over time compared with those in usual care (z = -3.06, P<.002); however, this difference was not present in the more severely depressed groups (z = 0.61, NS). Although the group with severe depression showed differences between the intervention and control groups from baseline to 3 months that were similar to the group with less severe depression (during the acute phase of the intervention), these differences disappeared by 6 months.

CONCLUSIONS

Initial depression severity, comorbid panic disorder, and other psychosocial vulnerabilities were associated with a decreased response to the collaborative care intervention. Although the intervention was appropriate for patients with moderate depression, individuals with higher levels of depression may require a longer continuation phase of therapy in order to achieve optimal depression outcomes.

Can depression treatment in primary care reduce disability? A stepped care approach

OBJECTIVE

To assess effects of stepped collaborative care depression intervention on disability.

DESIGN

Randomized controlled trial.

SETTING

Four primary care clinics of a large health maintenance organization.

PATIENTS

Two hundred twenty-eight patients with either 4 or more persistent major depressive symptoms or a score of 1.5 or greater on the Hopkins Symptom Checklist. Depression items were randomized to stepped care intervention or usual care 6 to 8 weeks after initiating antidepressant medication.

INTERVENTION

Augmented treatment of persistently depressed patients by an on-site psychiatrist collaborating with primary care physicians. Treatment included patient education, adjustment of pharmacotherapy, and proactive monitoring of outcomes.

MAIN OUTCOME MEASURES

Baseline, 1-, 3-, and 6-month assessments of the Sheehan Disability Scale and the social function and role limitation subscales of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36).

RESULTS

Patients who received the depression intervention experienced less interference in their family, work, and social activities than patients receiving usual primary care (Sheehan Disability Scale, z = 2.23; P =.025). Patients receiving intervention also reported a trend toward more improvement in SF-36-defined social functioning than patients receiving usual care (z = 1.63, P =.10), but there was no significant difference in role performance (z = 0.07, P =.94).

CONCLUSIONS

Significant disability accompanied depression in this persistently depressed group. The stepped care intervention resulted in small to moderate functional improvements for these primary care patients. Arch Fam Med. 2000;9:1052-1058

Morphological phenotypes in neoplastic progression of benz(alpha)pyrene-treated breast epithelial cells

The neoplastic conversion of a normal cell to a malignant one is a multistage process that occurs after a series of molecular alterations. Several chemical and physical agents can alter the morphology of different types of cells. Scanning and transmission electron microscopy have been valuable in evaluating changes that occur in the progression of transformation. MCF-10F, a spontaneously immortalized human breast epithelial cell line (Soule et al., 1990), was treated with benz(alpha)pyrene (BP) (Calaf and Russo, 1993) and then transfected with the c-Ha-ras oncogene (Calaf et al., 1995). The phenotypic changes of breast cancer progression were studied through the use of scanning and transmission electron microscopy. Activated oncogenes have been detected in a variety of malignant tumors and the altered expression of certain genes seems to play a role in the cancer process. Carcinogen-treated and transfected cells showed a progression of changes in the morphology, anchorage independent growth, invasiveness and capability of tumor formation in the SCID mice. This in vitro cancer model can parallel the progression of breast cancer seen through molecular changes that occur and have been observed during the natural development of this disease.

Lipid and lipoprotein profiles, cardiovascular fitness, body composition, and diet during and after resistance, aerobic and combination training in young women

The purpose of this study was to evaluate the effects of various modes of training on the time-course of changes in lipoprotein-lipid profiles in the blood, cardiovascular fitness, and body composition after 16 weeks of training and 6 weeks of detraining in young women. A group of 48 sedentary but healthy women [mean age 20.4 (SD 1) years] were matched and randomly placed into a control group (CG, n = 12), an aerobic training group (ATG, n = 12), a resistance training group (RTG, n = 12), or a cross-training group that combined both aerobic and resistance training (XTG, n = 12). The ATG, RTG and XTG trained for 16 weeks and were monitored for changes in blood concentrations of lipoprotein-lipids, cardiovascular fitness, body composition, and dietary composition throughout a 16 week period of training and 6 weeks of detraining. The ATG significantly reduced blood concentrations of triglycerides (TRI) (P < 0.05) and significantly increased blood concentrations of high-density lipoprotein-cholesterol (HDL-C) after 16 weeks of training. The correlation between percentage fat and HDL-C was 0.63 (P < 0.05), which explained 40% of the variation in HDL-C, while the correlation between maximal oxygen uptake (VO2max) and HDL-C was 0.48 (P < 0.05), which explained 23% of the variation in HDL-C. The ATG increased VO2max by 25% (P < 0.001) and decreased percentage body fat by 13% (P < 0.05) after 16 weeks. Each of the alterations in the ATG had disappeared after the 6 week detraining period. The concentration of total cholesterol (TC), TRI, HDL-C and low density lipoprotein-cholesterol in the blood did not change during the study in RTG, XTG and CG. The RTG increased upper and lower body strength by 29% (P < 0.001) and 38%, respectively. The 6 week detraining strength values obtained in RTG were significantly greater than those obtained at baseline. The XTG increased upper and lower body strength by 19% (P < 0.01) and 25% (P < 0.001), respectively. The 6 week detraining strength values obtained in XTG were significantly greater than those obtained at baseline. The RTG, XTG and CG did not demonstrate any significant changes in either VO2max, or body composition during the training and detraining periods. The results of this study suggest that aerobic-type exercise improves lipoprotein-lipid profiles, cardiorespiratory fitness and body composition in healthy, young women, while resistance training significantly improved upper and lower body strength only.

RNA relocation at mitosis in transformed and tumorigenic human breast epithelial cells

The fate of RNA revealed by metachromatic staining after a critical electrolyte concentration assay using toluidine blue and Mg(2+)ions as competitors for the substrate dye binding sites was followed at mitosis in human breast epithelial cells transformed by benzo[a]pyrene and transfected with the c-Ha- ras oncogene. The aim was to detect changes in RNA distribution during mitosis in human transformed/tumorigenic cells exhibiting increased nucleolar sizes and rRNA production while in interphase. RNA relocation in association with the mitotic spindle fibers was observed from metaphase to telophase not to vary in all the cell lines studied. RNA-containing nucleolus-like bodies persistent during mitosis were found to decrease in frequency in the transformed and tumorigenic cells in comparison with control non-transformed cells simultaneously to the previously reported increase in nucleolar areas for the same cells while in interphase. It is suggested that an improved use of RNA transcripts has been developed with cell transformation and tumorigenesis in this particular model.

Activation of NF-kappaB/Rel occurs early during neoplastic transformation of mammary cells

NF-kappaB/Rel is a family of transcription factors which are expressed in all cells; however, in most non-B cells, they are sequestered in the cytoplasm in inactive complexes with specific inhibitory proteins, termed IkappaBs. We have recently shown that NF-kappaB/Rel factors are aberrantly activated in human breast cancer and rodent mammary tumors, and function to promote tumor cell survival and proliferation. Here, we have examined the time-course of induction of NF-kappaB/Rel factors upon carcinogen treatment of female Sprague-Dawley (S-D) rats in vivo and in human mammary epithelial cells (HMECs) in culture. We observed that NF-kappaB/Rel activation is an early event, occurring prior to malignant transformation. In S-D rats, increased NF-kappaB/Rel binding was detected in nuclear extracts of mammary glands from 40% of animals 3 weeks post-treatment with 15 mg/kg 7,12-dimethylbenz[a]anthracene (DMBA); this is prior to formation of tumors which normally begin to be detected after 7-9 weeks. In non-tumorigenic MCF-10F cells, in vitro malignant transformation upon treatment with either DMBA or benzo[a]pyrene (B[a]P) resulted in a 4- to 12-fold increase in activity of classical NF-kappaB (p65/p50). NF-kappaB induction was corrrelated with a decrease in the stability of the NF-kappaB-specific inhibitory protein IkappaB-alpha. Ectopic expression of the transactivating p65 subunit of NF-kappaB in MCF-10F cells induced the c-myc oncogene promoter, which is driven by two NF-kappaB elements, and endogenous c-Myc levels. Furthermore, reduction mammoplasty-derived HMECs, immortalized following B[a]P exposure, showed dysregulated induction of classical NF-kappaB prior to malignant transformation. Together these findings suggest that activation of NF-kappaB plays an early, critical role in the carcinogen-driven transformation of mammary glands.

Atlas and histologic classification of tumors of the rat mammary gland

Studies performed in experimental animal models have demonstrated that mammary cancer is a complex multistep process that can be induced either by chemicals, radiation, viruses, or genetic factors. Rodent models have been useful for dissecting the initiation, promotion, and progression steps of mammary carcinogenesis. Chemically induced mammary tumors, such as those induced by 7,12-dimethylbenz(a)anthracene and N-methyl-N-nitrosourea, are, in general, hormone-dependent adenocarcinomas whose incidence, number of tumors per animal, tumor latency, and tumor type are influenced by the age, reproductive history, and endocrinologic milieu of the host at the time of carcinogen exposure as well as by diet and the dose of carcinogen administered. There is a need to classify tumors according to their histopathological type because those characteristics have implications in the interpretation of experimental data. In the classification presented here we attempt to provide a working framework for diagnosis of the type of lesions found in the mammary glands of rats treated with chemical carcinogens or radiation and to clarify criteria for establishing the basic biological characteristics of tumors.

The mammary pathology of genetically engineered mice: the consensus report and recommendations from the Annapolis meeting

NIH sponsored a meeting of medical and veterinary pathologists with mammary gland expertise in Annapolis in March 1999. Rapid development of mouse mammary models has accentuated the need for definitions of the mammary lesions in genetically engineered mice (GEM) and to assess their usefulness as models of human breast disease. The panel of nine pathologists independently reviewed material representing over 90% of the published systems. The GEM tumors were found to have: (1) phenotypes similar to those of non-GEM; (2) signature phenotypes specific to the transgene; and (3) some morphological similarities to the human disease. The current mouse mammary and human breast tumor classifications describe the majority of GEM lesions but unique morphologic lesions are found in many GEM. Since little information is available on the natural history of GEM lesions, a simple morphologic nomenclature is proposed that allows direct comparisons between models. Future progress requires rigorous application of guidelines covering pathologic examination of the mammary gland and the whole animal. Since the phenotype of the lesions is an essential component of their molecular pathology, funding agencies should adopt policies ensuring careful morphological evaluation of any funded research involving animal models. A pathologist should be part of each research team.

Shorter hospital stays and more rapid improvement among patients with schizophrenia and substance disorders

OBJECTIVE

Length of stay and treatment response of inpatients with acute schizophrenia were examined to determine whether differences existed between those with and without comorbid substance-related problems.

METHODS

The sample comprised 608 patients with a diagnosis of schizophrenia or schizoaffective disorder treated on hospital units with integrated dual diagnosis treatment. They were rated on admission and discharge by a psychiatrist using a structured clinical instrument. Patients with no substance-related problems were compared with those with moderate to severe problems using t tests, chi square tests, and analysis of variance.

RESULTS

When analyses controlled for age, gender, and other clinical variables, dually diagnosed patients were found to have improved markedly faster compared with patients without a dual diagnosis. Their hospital stays were 30 percent shorter on both voluntary and involuntary units. They also showed somewhat greater symptomatic improvement and no increase in 18-month readmission rates. On admission the dual diagnosis group was more likely to be younger, male, and homeless and more likely to be a danger to self and others. Severity of psychosis was the same at admission for the two groups, but the dually diagnosed patients were rated as less psychotic at discharge.

CONCLUSIONS

Dually diagnosed patients with schizophrenia appear to stabilize faster during acute hospitalization than those without a dual diagnosis. The authors hypothesize that substance abuse may temporarily amplify symptoms or that these patients may have a higher prevalence of better-prognosis schizophrenia. The availability of integrated dual-focus inpatient treatment and a well-developed outpatient system may also have helped these patients recover more rapidly.

S100P calcium-binding protein overexpression is associated with immortalization of human breast epithelial cells in vitro and early stages of breast cancer development in vivo

The mechanism of cell immortalization of human breast epithelial cells leading to neoplastic transformation is not clear. The isolation and characterization of a spontaneously immortalized human breast epithelial cell line, MCF-10F, have provided a valuable tool to identify genes involved in this process. Using the technique of differential display, we have identified seven cDNA bands differentially displayed in the MCF-10F cells when compared with the mortal S130 cells from which MCF-10F was originated. One of these bands was isolated and cloned. Sequence analysis revealed 99% homology to the EF-hand calcium-binding protein S100P (Placental). The clone was overexpressed in the immortal cell line MCF-10F when compared to the mortal counterpart S130 or other primary cultures of human breast epithelial cells. In addition, it was highly expressed in chemically transformed breast epithelial cell lines (BP1E and D3. 1), breast cancer cell line T47D, as well as in three invasive ductal carcinomas when compared to their normal adjacent tissue. The S100P protein was localized by immunohistochemistry, using a monoclonal antibody against the same amino acid sequence of the gene cloned, in ductal hyperplasias, in situ and invasive ductal carcinoma, but not in the normal tissues. We concluded that S100P overexpression is an early event that might play an important role in the immortalization of human breast epithelial cells in vitro and tumor progression in vivo.

Morphological phenotypes in neoplastic progression of human breast epithelial cells

Neoplastic progression is a prolonged and stepwise process, while tumor growth occurs after a series of molecular alterations that culminate in tumorigenesis. The phenotypic changes of transformation in breast carcinogenesis were studied through the use of scanning and transmission electron microscopy. MCF 10F, a spontaneously immortalized human breast epithelial cell line (Soule et al., 1990), was treated with 7,12 dimethylbenz(a)anthracene (DMBA) (Calaf and Russo, 1993) and then transfected with the c-Ha-ras oncogene (Calaf et al., 1995). Treated cells showed a progression in altered morphology, anchorage independency, invasiveness and tumorigenicity in the SCID. Scanning and transmission electron microscopy illustrated that the transformed cells could be distinguished from control cells by the expression of morphological characteristics such as loss of contact inhibition, irregular size and shape, emission of long filopodia and formation of stratified layers. In contrast, control cells showed uniform, flattened and polyhedrical cells, well closely juxtaposed to each other and joined by cytoplasmic interdigitations. Control cells also did not form colonies in agar-methocel, and were not invasive or tumorigenic in SCID mice. These studies showed the progression of breast carcinogenesis by phenotypical changes induced by the carcinogen and the insertion of the c-Ha-ras oncogene.

Hormonal approach to breast cancer prevention

Breast cancer is more frequent in nulliparous women, while its incidence is significantly reduced by full-term pregnancy. The fact that the protection conferred by pregnancy is observed in women from different countries and ethnic groups, regardless of the endogenous incidence of this malignancy, indicates that this protection does not result from extrinsic factors specific to a particular environmental, genetic, or socioeconomic setting, but rather from an intrinsic effect of parity on the biology of the breast. Using an experimental system we have shown that treatment of young virgin rats with human chorionic gonadotropin (hCG), like full-term pregnancy, efficiently inhibits the initiation and progression of chemically induced mammary carcinomas. Treatment of young virgin rats with hCG induced a profuse lobular development of the mammary gland, reduced the proliferative activity of the mammary epithelium, and induced the synthesis of inhibin, a secreted protein with tumor-suppressor activity. HCG treatment also increased the expression of the programmed cell death (PCD) genes testosterone repressed prostate message 2 (TRPM2), interleukin 1-beta-converting enzyme (ICE), p53, c-myc, and bcl-XS, induced apoptosis, and downregulated cyclins. PCD genes were activated through a p53-dependent process, modulated by c-myc, and with partial dependence on the bcl-2 family-related genes. The possibility that this hormonal treatment activates known or new genes was tested by differential display technique. We have identified a series of new genes, hormone-induced-1 (HI-1) among them. The characterization of their functional role will contribute to clarify the mechanisms through which hCG inhibits the initiation and progression of mammary cancer. Of great significance was the observation that PCD genes remained activated even after lobular formations had regressed due to the cessation of hormone administration. We postulate that this mechanism plays a major role in the long-lasting protection exerted by hCG from chemically induced carcinogenesis, and might be also involved in the lifetime reduction in breast cancer risk induced in women by full-term pregnancy. The implications of these observations are two-fold: on one hand, they indicate that hCG, as pregnancy, may induce early genomic changes that control the progression of the differentiation pathway, and on the other, that these changes are permanently imprinted in the genome, regulating the long-lasting refractoriness to carcinogenesis. The permanence of these changes, in turn, makes them ideal surrogate markers of hCG effect in the evaluation of this hormone as a breast cancer preventive agent.

Apoptosis and catastrophic cell death in benzo[a]pyrene-transformed human breast epithelial cells

Apoptosis and mitotic death, bi- and multinucleation, giant cells and micronucleation were investigated in human breast epithelial cell lines transformed by benzo[a]pyrene (BP) (BP1, BP1-E and BP1-E1 cells) and in BP1 cells transfected with the c-Ha-ras oncogene (BP1-Tras cells). Since BP induces apoptosis and the abnormal expression of ras genes elicits catastrophic mitosis, both cell death phenomena were expected to occur in this system, especially in BP1-Tras cells. Regardless of the cell line considered, single-nucleate cells were found to be eliminated preferentially through apoptosis, while bi- and multinucleate cells were eliminated through catastrophic mitosis. Apoptosis and catastrophic mitosis were observed in all cell lines but were significantly more frequent in BP1-Tras cells. The abnormal expression of Ha-ras in the latter cells may enhance in this system the effects of the BP apoptosis path reported for BP-transformed Hepa 1c1c7 hepatoma cells. Transfection with the ras oncogene also enhanced the mitotic disturbances, which produced multi- and micronucleation and mitotic death, possibly because of the genomic instability promoted by this oncogene in the BP-transformed cell line.

Stepped collaborative care for primary care patients with persistent symptoms of depression: a randomized trial

BACKGROUND

Despite improvements in the accuracy of diagnosing depression and use of medications with fewer side effects, many patients treated with antidepressant medications by primary care physicians have persistent symptoms.

METHODS

A group of 228 patients recognized as depressed by their primary care physicians and given antidepressant medication who had either 4 or more persistent major depressive symptoms or a score of 1.5 or more on the Hopkins Symptom Checklist depression items at 6 to 8 weeks were randomized to a collaborative care intervention (n = 114) or usual care (n = 114) by the primary care physician. Patients in the intervention group received enhanced education and increased frequency of visits by a psychiatrist working with the primary care physician to improve pharmacologic treatment. Follow-up assessments were completed at 1, 3, and 6 months by a telephone survey team blinded to randomization status.

RESULTS

Those in the intervention group had significantly greater adherence to adequate dosage of medication for 90 days or more and were more likely to rate the quality of care they received for depression as good to excellent compared with usual care controls. Intervention patients showed a significantly greater decrease compared with usual care controls in severity of depressive symptoms over time and were more likely to have fully recovered at 3 and 6 months.

CONCLUSIONS

A multifaceted program targeted to patients whose depressive symptoms persisted 6 to 8 weeks after initiation of antidepressant medication by their primary care physician was found to significantly improve adherence to antidepressants, satisfaction with care, and depressive outcomes compared with usual care.

Cellular basis of breast cancer susceptibility

Breast cancer originates in undifferentiated terminal structures of the mammary gland. The terminal duct of the Lob 1 of the human female breast is the site of origin of ductal carcinomas. Cell replication and the concentration of estrogen receptors type at in Lob 1 are at their peak during early adulthood, at a time during which the breast is more susceptible to carcinogenesis, decreasing considerably with aging. More importantly, when treated with carcinogens in vitro they express phenotypes indicative of cell transformation. These studies indicate that in humans there is a target cell of carcinogenesis, which is found in a specific compartment whose characteristics are a determinant factor in the initiation event. These target cells will become the stem cells of the neoplastic event, depending upon: a) topographic location within the mammary gland tree, b) age at exposure to a known or putative genotoxic agent, and c) reproductive history of the host. Epidemiological findings such as the higher incidence of breast cancer in nulliparous women and in women having early menarche support this concept, because it parallels the higher cancer incidence elicited by carcinogens when exposure occurs at a young age. In addition, it has been shown that increase in parity is associated with a pronounced decrease in the risk of breast cancer, each additional live birth conferring a 10% risk reduction. Thus, the protection afforded by early full-term pregnancy in women could be explained by the higher degree of differentiation of the mammary gland at the time in which an etiologic agent or agents act. The relevance of our work lies in the side by side comparison of in vivo and in vitro studies in the human breast that validates experimental data for extrapolation to the human situation. The finding that cell proliferation is of importance for cancer initiation, whereas differentiation is a powerful inhibitor, provides novel tools for developing rational strategies for breast cancer prevention and control.

Functional roles of chromosomes 11 and 17 in the transformation of human breast epithelial cells in vitro

Genomic alterations in primary breast cancer play a role in the initiation and progression of the disease. We have analyzed the molecular events involved in the initiation and progression of the neoplastic process in an in vitro experimental system. Immortalization of human breast epithelial cells (HBEC) is associated with 3:9 translocation, p53 mutation and microsatellite instability (MSI) of chromosomes 11p13, and 17p. BP1-E cells, derived from the immortalized MCF-10F cells transformed by the carcinogen benzo(a)pyrene (BP), express in vitro growth advantage, anchorage independence, enhanced chemoinvasiveness, loss of ductulogenic capabilities and tumorigenesis in a heterologous host. This neoplastic progression is also associated with mutations and/or amplification of c-H-ras, int-2, c-neu, c-myc and MDM2, MSI at 11q25 and 13q12-q13 and loss of heterozygosity at 17p. In order to test whether chromosomes 11 or 17 play a functional role in the phenotypic expression of transformation of BP1E cells, we utilized microcell-mediated chromosome transfer (MMCT) technique for inserting the corresponding normal chromosomes to these transformed cells. BP1E cells were transfected with PsV2neo plasmid and fused with microcells obtained from the mouse cell line A9, containing a normal chromosome 11 or 17 (A9-11neo and A9-17neo cells, selected in G418 and cloned. Sixteen primary microcell hybrids from each chromosome transfer, designated BP1E-11neo and BP1E-17neo survived selection in G-418 containing medium. A single clone from each group, BP1E-11neo #145 and BP1E-17neo D100, survived subcloning and were utilized for a detailed panel of analyses. The presence of a donor chromosome was confirmed by dual color fluorescence in situ hybridization (FISH), southern blot analysis of the marker vector pSV2neo, and microsatellite polymorphism analysis. The transfer of the normal chromosomes 11 and 17 resulted in a 50% and 90% inhibition of cell growth respectively, and reduced both colony efficiency and colony size. Telomerase activity was significantly reduced only by chromosome 17 insertion, providing a possible explanation for the more significant senescence observed in BP1E-17neo D100 cells. Microsatellite polymorphism analysis revealed that three loci, 11q13-23, 11q23.1, and 11q23.3 (markers D11S911, DRD2, and D11S29) were retained in BP1E-11neo #145 cells, and two, 17q24.2-25.2, 17q25.2 (markers D17S515 and D17S785 were retained in BP1E-17neo D100 cells. We conclude that the specific regions of normal chromosomes 11 and 17 transferred play a functional role in the expression of immortal and transformed phenotypes of HBEC in vitro.