Activity of Estrogen Receptor β Agonists in Therapy-Resistant Estrogen Receptor-Positive Breast Cancer

Background

Among women, breast cancer is the leading cause of cancer-related death worldwide. Estrogen receptor α-positive (ERα+) breast cancer accounts for 70% of all breast cancer subtypes. Although ERα+ breast cancer initially responds to estrogen deprivation or blockade, the emergence of resistance compels the use of more aggressive therapies. While ERα is a driver in ERα+ breast cancer, ERβ plays an inhibitory role in several different cancer types. To date, the lack of highly selective ERβ agonists without ERα activity has limited the exploration of ERβ activation as a strategy for ERα+ breast cancer.

Methods

We measured the expression levels of ESR1 and ESR2 genes in immortalized mammary epithelial cells and different breast cancer cell lines. The viability of ERα+ breast cancer cell lines upon treatments with specific ERβ agonists, including OSU-ERb-12 and LY500307, was assessed. The specificity of the ERβ agonists, OSU-ERb-12 and LY500307, was confirmed by reporter assays. The effects of ERβ agonists on cell proliferation, cell cycle, apoptosis, colony formation, cell migration, and expression of tumor suppressor proteins were analyzed. The expression of ESR2 and genes containing ERE-AP1 composite response elements was examined in ERα+ human breast cancer samples to determine the correlation between ESR2 expression and overall survival and that of putative ESR2-regulated genes.

Results

In this study, we demonstrate the efficacy of highly selective ERβ agonists in ERα+ breast cancer cell lines and drug-resistant derivatives. ERβ agonists blocked cell proliferation, migration, and colony formation and induced apoptosis and S and/or G2/M cell-cycle arrest of ERα+ breast cancer cell lines. Also, increases in the expression of the key tumor suppressors FOXO1 and FOXO3a were noted. Importantly, the strong synergy between ERβ agonists and ERα antagonists suggested that the efficacy of ERβ agonists is maximized by combination with ERα blockade. Lastly, ESR2 (ERβ gene) expression was negatively correlated with ESR1 (ERα gene) and CCND1 RNA expression in human metastatic ERα+/HER2- breast cancer samples.

Conclusion

Our results demonstrate that highly selective ERβ agonists attenuate the viability of ERα+ breast cancer cell lines in vitro and suggest that this therapeutic strategy merits further evaluation for ERα+ breast cancer.

Degradation of crude oil by marine cyanobacteria

The marine cyanobacteria Oscillatoria salina Biswas, Plectonema terebrans Bornet et Flahault and Aphanocapsa sp. degraded Bombay High crude oil when grown in artificial seawater nutrients as well as in plain natural seawater. Oil removal was measured by gravimetric and gas chromatographic methods. Around 45-55% of the total fractions of crude oil (containing 50% aliphatics, 31% waxes and bitumin, 14% aromatics and 5% polar compounds) were removed in the presence of these cultures within 10 days. Between 50% and 65% of pure hexadecane (model aliphatic compound) and 20% and 90% of aromatic compounds (anthracene and phenantherene) disappeared within 10 days. Mixed cultures of the three cyanobacterial species removed over 40% of the crude. Additionally, these cultures formed excellent cyanobacterial mats when grown in mixed cultures, and thus have the potential for use in mitigating oil pollution on seashores, either individually or in combination.

The use of demeclocycline in the treatment of patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Eight patients (7 men and 1 woman, mean age 43.1 +/- 8.9 years) with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent treatment with demeclocycline in an effort to normalize serum sodium levels and thereby protect the PIP patients against complications including hyponatremic seizures and coma. There tended to be an improvement (p = .080) in early morning serum sodium following treatment with demeclocycline (baseline 132.6 +/- SD 3.3 and treatment serum sodium 134.8 +/- SD 3.3 mEq/1). At the same time, there was an increase (p = .043) in urinary specific gravity following treatment with demeclocycline (baseline 1.0047 +/- SD .0029 and treatment urinary specific gravity 1.0063 +/- SD .0026). Clinical indications for and potential mechanisms of action of demeclocycline treatment in the PIP syndrome are discussed.

Treatment of psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) using lithium and phenytoin

Six patients [5 men and 1 woman, mean age 37.3 +/- 8.2 (SD) years] with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent a sequence of treatments in an effort to normalize basal serum sodium levels and thereby protect the patients against complications, including hyponatremic seizures and coma. The morning baseline group mean basal serum sodium value was 132.5 +/- 3.8 meq/liter. Over a 20-month period, the sequence of treatments was salt-added diet, lithium and phenytoin, and lithium alone. Each treatment program yielded morning group mean basal serum sodium determinations superior to baseline values, except for the program of lithium alone, which could not be tolerated. The combination of lithium and phenytoin provided a morning group mean basal serum sodium level of 140.6 +/- 3.2 meq/liter, which was superior (p less than 0.01) to all other treatment modalities. Early morning hyposthenuria persisted throughout the 20-month period of observation.

Diurnal variation of urinary excretion for patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome)

Ten patients [8 men and 2 women, mean age (SD) 37.6 +/- 6.5 years] with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome) underwent serial determinations at 6:00 AM, 12 noon, 6:00 PM, and 12 midnight of levels of urinary creatinine concentration (UCR), urinary specific gravity (SPGR), and urinary osmolality (UOSM) on 8 consecutive Thursdays. Diurnal variation (p less than 0.015) was present in the case of each parameter of urinary excretion (UCR, SPGR, and UOSM). These three parameters remained very low throughout the day (mean UCR 19.0 mg/dl, mean SPGR 1.0033, and mean UOSM 112.6 mosmol/kg), which is consistent with severe and persistent hyposthenuria, and each parameter correlated well with the other two parameters (r between 0.78 and 0.93, p less than 0.001). The 6:00 PM (UC6PM) value for UCR correlated best with the daily mean UCR (UCM), providing the simple linear regression UCM = 0.7615 X UC6PM + 6.1503 (r = 0.912, p = 0.0005) for the 10 PIP patients. Twenty-four-hour urinary volume (24UV) could then be estimated using UCM and values of 17.5 and 12.5 mg creatinine/kg body weight for male and female PIP patients, respectively, to calculate the daily urinary excretion of urinary creatinine. The group mean 24UV was 6963 ml, with a range of 4934-9884 ml. We hope that information about the diurnal variation of urinary excretion (21.6%, 20.5%, 27.4%, and 30.4% of 24UV excreted in consecutive quartiles commencing with the 12 midnight to 6:00 AM quartile), coupled with the utilization of the equation UCM = 0.7615 X UC6PM + 6.1503 (r = 0.912, p = 0.0005) to estimate UCM as an index of 24UV in the PIP syndrome, will provide tools to better elucidate the relationship between psychosis and water dysregulation.

Correlation of cigarette-induced increase in serum nicotine levels with arginine vasopressin concentrations in the syndrome of self-induced water intoxication and psychosis (SIWIP)

Ten patients [9 men and 1 woman; mean age 42.4 +/- 8.5 (+/- SD) years] who were smokers and who suffered the complications of self-induced water intoxication and psychosis (SIWIP) (8 patients with schizophrenic disorders, 1 patient with manic-depressive illness, 1 patient with dementia) are reported. Each patient underwent serial determinations of parameters of water metabolism including plasma and urine osmolality and plasma arginine vasopressin (AVP). The syndrome of inappropriate antidiuresis (SIAD) was found in each patient. Because of the reported effect that cigarette smoking has on antidiuresis, we correlated serum nicotine (NIC) levels with plasma and urine osmolality, AVP, and 24-hour urine volume (24 degrees-UV). We found no relationship between NIC and plasma or urine osmolality, AVP, or 24 degrees-UV. In the presence of SIWIP and SIAD, we infer the limbic-hypothalamic neurotransmitters in these psychotic patients are sufficiently powerful in stimulating both compulsive water drinking and inappropriate release of AVP so as to overshadow any effects that NIC may have on water metabolism.

Polyuria among patients with psychosis

Using the criterion of early morning urinary specific gravity (SPGR) of 1.008 or less to define the presence of polyuria, we identified 26 of 72 male (36 percent) and 14 of 31 female (45 percent) institutionalized chronically psychotic patients as polyuric during a comprehensive survey of one of the chronic care units at a State mental hospital. Factors including diagnosis, sex, age, weight, and serum sodium did not distinguish the polyuric from the nonpolyuric patients. For men, administration of lithium was associated with polyuria. Urinary creatinine concentration (UCR) correlated well with SPGR, and UCR may provide an alternate index to separate polyuric from nonpolyuric patients. The clinical implications of our findings are discussed.

Psychogenic polydipsia and water intoxication--concepts that have failed

Ten patients (8 men, 2 women; mean age 38.7 +/- 8.1 years), 7 of whom had schizophrenic disorders and 3 of whom had bipolar disorder (manic-depressive illness), manifested psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome). The relationship between serum sodium and urinary water excretion among the 10 PIP patients is described in detail. The success of lithium in improving serum sodium levels and in decreasing urinary water excretion among the three PIP patients with bipolar disorder and the failure of changes in urinary water excretion to explain changes in serum sodium levels among the 10 PIP patients argue against "psychogenesis" as the explanation for the polydipsia and excessive water intake as the sole explanation for hyponatremia or complications ascribed to water intoxication.

Patterns of urinary excretion among patients with self-induced water intoxication and psychosis

Parameters of water metabolism were measured serially in nine patients with the syndrome of self-induced water intoxication and psychosis (SIWIP). Clinical and laboratory findings indicated that SIWIP patients are type A of the syndrome of inappropriate antidiuresis. Estimated 24-hour urinary excretion of creatinine and early morning urinary creatinine concentration measurements were used to calculate 24-hour urine volumes. Polyuria was considered present for male patients when excretion was estimated to be greater than 2,600 ml of urine/24 hours or early morning urinary specific gravity was less than or equal to 1.003. Male patients with a specific gravity of less than or equal to 1.003 predictably excreted 28,000 ml of urine/day. Severe hyposthenuria may be a biological marker for a population at risk to develop complications of SIWIP, including seizures, coma, and death.

Death from self-induced water intoxication among patients with schizophrenic disorders

Review of 60 consecutive records of patients who died before the age of 53 years in a state mental hospital revealed that 27 of those patients (45%) had a schizophrenic disorder. Of those 27 patients, five (18.5%) died of the complications of self-induced water intoxication and schizophrenic disorders (SIWIS). Clinical, laboratory, and autopsy features of those five SIWIS patients and of an additional five SIWIS cases obtained from the literature include psychosis, polydipsia, polyuria, severe hyposthenuria (specific gravity 1.003 or less), hyponatremia, seizures, coma, and cerebral and visceral edema. SIWIS characteristically develops during Arieti's third or "preterminal" stage (5 to 15 years after onset of psychosis) of schizophrenic disorders and it must be included in the differential diagnosis of unexplained death among psychiatric patients. As there are no pathognomonic SIWIS tissue changes, the pathologist must carefully integrate clinical, laboratory, and autopsy findings to arrive at the proper diagnosis. When premortem findings of polydipsia and hyponatremia are not available, evidence of antecedent severe hyposthenuria and postmortem vitreous humor hyponatremia of less than 120 mEq/1 are strongly supportive of the diagnosis of death due to SIWIS.

Oral sodium chloride in the management of schizophrenic patients with self-induced water intoxication

Hyponatremia is always present in patients with water intoxication and accounts for many of the life-threatening symptoms and signs found in this population. In schizophrenic patients, water restriction, a cornerstone in the treatment of water intoxication, may be impossible to implement over the course of long-term management. The use of oral sodium chloride administration in such patients and its short-term efficacy in preventing major motor seizures are described.

Evaluation of patients with self-induced water intoxication and schizophrenic disorders (SIWIS)

The complications of water intoxication are well documented in the medical literature. Less well appreciated is the frequent appearance of self-induced water intoxication in patients with schizophrenic disorders. Six such patients are described and compared with the findings in the literature. Nonedematous, nonhypovolemic hyponatremia is the invariable biochemical abnormality in this syndrome and its multiple causes are discussed, including the syndrome of inappropriate antidiuresis. Severe hyposthenuria (urinary specific gravity 1.003 or less) is the silent biological marker that always antedates the complications of self-induced water intoxication and schizophrenic disorders (SIWIS). While recognizing that all patients with polydipsia do not go on to develop water intoxication, this biological marker provides the means to detect patients who may be destined to develop SIWIS; early recognition may prevent the major complications of this syndrome.

[Malignant syndrome in burned children. Nosologic and therapeutic approach]

A malignant syndrome was observed in 7 children less than 3 years old; the extent of burn was between 5 and 25 p. cent. This syndrome appeared between the second and the fifth days. It was characterized by fever, autonomic disorders and finally coma. The clinical, biological and anatomical features look like the syndrome of Reye. The use of dopamine before coma allowed healing.