[The triglyceride glucose index predicts the risk of nonfatal cardio-cerebrovascular disease in the Beijing community: a prospective cohort study].

Objective: To explore the characteristics of the association between the triglyceride glucose (TyG) index and nonfatal cardio-cerebrovascular disease risk in a community population. Method: This was a prospective cohort study. From December 2011 to April 2012, the first investigation was conducted among subjects with more than 40-year old who were from Shijingshan district and Pingguoyuan community in Beijing. The second investigation was conducted from April to October 2015. All the subjects were divided into three groups according to the tertile of the TyG index at baseline. The multivariate Cox proportional risk regression model was established to explore the correlation between the TyG index and nonfatal cardio-cerebrovascular disease risk and the Kaplan-Meier survival curve of the TyG index group was drawn. Subgroup analyses were performed according to age, gender, body mass index, type 2 diabetes mellitus (T2DM), hypertension, and hyperlipidemia to determine the correlation characteristics between the TyG index and nonfatal cardio-cerebrovascular disease among subgroups. Results: A total of 9 577 subjects were finally included to analyze. The mean follow-up time of this study was (34.14±3.84) months. During the follow-up, 363 subjects (3.8%) occurred nonfatal cardio-cerebrovascular disease. The multivariate Cox regression analysis results showed that the hazard ratio (HR) of nonfatal cardio-cerebrovascular disease in the high TyG index group was 1.54 (95%CI 1.19-1.98), 1.60 (95%CI 1.23-2.10), and 1.57 (95%CI 1.20-2.05) in the three models, compared with the low TyG index group. The Kaplan-Meier analysis showed that the risk of nonfatal cardio-cerebrovascular disease increased from the low-TyG index group to the high-TyG index group (P=0.015). In the six subgroups analysis, only gender was shown to have a significant interaction effect with the TyG index and nonfatal cardio-cerebrovascular disease risk. In the female population, the risk of nonfatal cardio-cerebrovascular disease is significantly increased with the increase in the TyG index level (P<0.001). Conclusions: A high TyG index is independently related to the increased risk of nonfatal cardio-cerebrovascular disease in the Beijing community population. Gender has a significant interaction with the TyG index and nonfatal cardio-cerebrovascular disease risk. Therefore, the TyG index may be a useful marker to predict the nonfatal cardio-cerebrovascular disease risk of a community population.

[Diagnosis and treatment of 21-hydroxylase deficiency with testicular adrenal rest tumors:a report of three cases and literature review].

Objective: To provide insight into the diagnosis for clinicians, the clinical characteristics, diagnosis and treatment history of 3 patients with 21-hydroxylase deficiency (21-OHD) and testicular adrenal rest tumors (TART) were analyzed. Methods: The clinical, laboratory and imaging data of 3 male patients with 21-OHD and TART, confirmed with CYP21 gene sequencing, from May 2010 to May 2021 in the First Medical Center of Chinese PLA General Hospital were analyzed retrospectively. The treatment strategy and clinical outcome were followed up. Results: All the 3 patients were first diagnosed with bilateral adrenal mass at the age of 27-42 years old. They were 145-162 cm tall. The levels of progesterone, 17-hydroxyprogesterone, and adrenocorticotropic hormone (ACTH) of the 3 patients were relatively high, and that of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) of the 3 patients were low. Testosterone level of 1 patient was significantly elevated, and that of the other 2 patients was below the lower limit of normal range. Testicular ultrasound showed heterogeneous hyperechoic masses in both testes. CT of the adrenal glands showed bilateral adrenal enlargement with mass. All 3 patients were treated with dexamethasone. After 4-96 months of follow-up, 17-hydroxyprogesterone level was kept above the median normal level. One of the patients got married and had a baby after treatment. The sizes of adrenal hyperplasia and testicular masses reduced to various degrees with the change of the testicular masses being proportional to that of adrenal hyperplasia. Conclusions: Patients with 21-OHD are prone to have TART, leading to the impaired testicular function. Early glucocorticold therapy is beneficial to the reduction of TART and restoration of testicular function.

[Clinical aspects of pregnancy-related lymphocytic hypophysitis].

Objective: To analyze clinical features, diagnosis, treatment and prognosis of pregnancy-related lymphocytic hypophysitis (LyH). Methods: The clinical data of 16 cases diagnosed as pregnancy-related LyH at Chinese PLA General Hospital between October 2010 and November 2019 were reviewed. Results: Sixteen patients were included (aged 20-40 years). All patients' symptoms occurred from the last 2 months of pregnancy to 12 months postpartum, with 6 cases in the third trimester and 10 cases during postpartum, and all the patients were diagnosed after delivery. Six patients had lymphocytic adenohypophysitis (LAH), 4 patients had lymphocytic infundibuloneurohypophysitis (LINH), 4 patients had lymphocytic panhypophysitis (LPH), and 2 had lymphocytic hypothalamitis. Eight patients presented with symptoms of intracranial space-occupying lesions, 14 patients had symptoms of anteriorpituitary hormone deficiencies, 9 patients had central diabetes insipidus (CDI), and 2 had hyperprolactinemia. Pituitary MRI showed that the pituitary presented with diffuse enlargement, pituitary stalk thickening, disappearing of high-intensity signals in posterior pituitary and space-occupying lesions in the infundibulum of hypothalamus. Nine patients were treated with immunosuppressive agent, 3 patients alleviated the space-occupying effects after surgery, and 4 patients recovered spontaneously. Fourteen patients were followed up with a period of 3-98 months. Four patients had a relapse, 2 patients had a complete remission, and 12 patients needed long-term hormone replacement therapy. Conclusions: Clinical manifestations of pregnancy-related LyH are diverse. LyH should be suspected in pregnant or postpartum women with a sellar mass to avoid missed diagnosis or misdiagnosis. Immunosuppressant therapy is effective. Overall, LyH patients have a favorable prognosis.

[Differences of brain functional alterations between subtypes of Cushing's syndrome patients].

Objective: To compare the differences of brain functional damage of subtypes of patients with Cushing's syndrome (CS). Methods: A total of 11 adrenocorticotropic hormone (ACTH)-dependent CS patients and 29 ACTH-independent CS patients were recruited from Chinese PLA General Hospital between September 2015 and March 2017 with confirmed CS. The psychiatric scales and brain task functional magnetic resonance imaging (fMRI) were evaluated. Results: A total of 40 patients (34 females, 6 males) with a mean age of (39.20±12.10) years and a median education level of 12 (9, 16) years were enrolled. ACTH-dependent patients had significantly worse performance than the ACTH-independent patients in response to the depression evaluation (64.6±6.1 vs 56.2±12.8, P=0.008), positive emotion (17.8±4.2 vs 24.3±7.2, P=0.008) and CS life quality [31(29,33) vs 42(29,51), P=0.040]. In the reaction to positive target pictures, ACTH-dependent CS patients showed stronger activation in left superior temporal gyrus compared with patients in ACTH-independent group, while the activation degree of their bilateral dorsal anterior cingulate cortex, bilateralsuperior frontal gyrus and left middle frontal gyrus was much worse. In the reactions to negative target pictures, ACTH-dependent CS patients had weaker activation in bilateral cerebellum, left superior frontal gyrus, left middle frontal gyrus, left precuneus and right postcentral gyrus, compared with patients in the ACTH-independent CS group (P<0.01, AlphaSim corrected). The activation degree of some regions whose brain function was different between the two groups was correlated to the cortisol level, ACTH level, 24 h urinary free cortisol (UFC) level, depression evaluation and negative emotion assessment (all P<0.05). Conclusions: The severity of the depression and the life quality of patients in ACTH-dependent group are worse than ACTH-independent CS patients. The brain function of ACTH-dependent CS patients is much weaker.

[Associated factors of intraoperative hemodynamic instability in patients with incidental pheochromocytomas].

Objective: To analyze the associated factors of intraoperative hemodynamic instability (HI) in patients with incidental pheochromocytomas. Methods: The data of 104 patients with a pathological diagnosis of pheochromocytoma at Chinese PLA General Hospital between January 2011 and December 2016 was retrospectively analyzed. The patients were divided into hemodynamic stability (HS) group (n=56) and HI group (n=48) according to hemodynamic characteristics. The clinical features, biochemical test, preoperative and intraoperative hemodynamics were analyzed. Multivariate logistic regression analysis was used to explore the associated factors of HI. Results: The age [(44.7±12.7) years vs (52.1±12.8) years], tumor diameter [(47.9±16.3) mm vs (57.9±21.6) mm], preoperative blood pressure [(121.3±11.5) mmHg vs (127.2±13.3) mmHg] in HS group were less than those in HI group (all P<0.05). The proportion of age ≥ 50 years (28.6% vs 64.6%), tumor diameter ≥ 45 mm (48.2% vs 68.8%) and hematocrit < 0.38 (25.0% vs 51.3%) in HS group were less than that in HI group (all P<0.05). Multivariate logistic regression analysis indicated that age ≥ 50 years (OR=7.940, 95% CI: 2.480-25.417, P<0.001), tumor diameter ≥ 45 mm (OR=5.042, 95% CI: 1.482-17.156, P=0.010), blood pressure ≥ 130/80 mmHg (OR=3.127, 95% CI: 1.034-9.463, P=0.044) and hematocrit < 0.38 (OR=6.273, 95% CI: 1.893-20.788, P=0.003) were independent associated factors of HI. The proportion of HI ( χ(2)=9.033, P=0.003) and intensive care unit (ICU) admission ( χ(2)=16.641, P<0.001) increased along with increasing associated factors. Conclusion: Adequate preoperative medical preparation and volume expansion for appropriate blood pressure are important for elder patients with large tumor to prevent HI in patients with incidental pheochromocytomas.

[Clinical characteristics of central diabetes insipidus: a retrospective analysis of 230 cases].

Objective: To evaluate the clinical characteristics and etiologies of central diabetes insipidus (CDI). Methods: The clinical data of 230 patients with CDI in the Department of Endocrinology of Chinese PLA General Hospital from 2008 June to 2014 December were collected and analyzed retrospectively. Results: The three most common causes of CDI were idiopathic CDI, lymphocytic hypophysitis and intracranial germ cell tumors. Among all the CDI, the idiopathic CDI accounted for 37.48%. There were significant differences in age onset and gender distribution among the different causes of CDI. The patients with intracranial germ cell tumors [age of onset(19.2±10.2) years] were younger than the other types of CDI. Germ cell tumors patients were more common in male, and lymphocytic hypophysitis patients were more common in female. The most frequent abnormality of anterior pituitary in patients with CDI was growth hormone deficiency, followed by hypogonadism, adrenal insufficiency and hypothyroidism. The dysfunction of thyroid axis and adrenal axis in patients with germ cell tumor was more common than those in patients with idiopathic and lymphocytic hypophysitis. Conclusions: The most common causes of central diabetes insipidus were idiopathic CDI, lymphocytic hypophysitis and intracranial germ cell tumors. There were differences in age of onset, gender distribution and abnormal production of anterior pituitary hormones among all causes of CDI patients.

[Clinical features and prognosis of 18 cases of primary lymphocytic hypophysitis].

Objective: To analyze clinical features, prognosis and treatment of lymphocytic hypophysitis (LYH). Methods: The clinical data, treatments and outcomes of 18 cases diagnosed as LYH at Chinese PLA General Hospital between January 2001 and July 2017 was respectively reviewed. Results: Eighteen patients with histology-proven LYH (13 females and 5 males ) were identified. All lymphocytic adenohypophysitis (LAH) were females(n=6), two of whom were associated with pregnancy. Eleven patients (6 females and 5 males) had lymphocytic panhypophysitis (LPH) and one(female) had hypothalamitis. Pre-treatment evaluation revealed that 11 patients presented with symptoms of intracranial space-occupying lesions, 12 patients had symptoms of anterior pituitary hormone deficiencies, and 12 patients had central diabetes insipidus (CDI). All patients had space-occupying lesions on magnetic resonance imaging (MRI), which were symmetrically enlarged and homogenously enhanced with or without pituitary stalk thickening. Before or after surgery, 11 patients received immunosuppressant therapy or radiotherapy to alleviate space-occupying effect. After 4-204 months follow-up, 5 patients had a relapse and received immunosuppressants, radiotherapy or surgery to achieve remission. Full recovery (both symptomatic and radiographic) was seen in 6 patients, and 11 patients maintained stable replacement therapy. Conclusions: LYH presents with acute space-occupying effects such as headache, visual disturbances, hypopituitarism, CDI and mild hyperprolactinemia, especially with characteristic radiographic manifestations. Usually, surgery reliably establishes diagnosis, and immunosuppressant therapy is a necessity. On the whole, LYH has a good prognosis.

[Diagnostic value of urinary free cortisol in the subclinical Cushing's syndrome in patients with adrenal incidentaloma].

Objective: To evaluate the efficacy of 24 h urinary free cortisol (24 h UFC) in the diagnosis of subclinical Cushing's syndrome (SCS), and explore the best diagnostic cut-off value. Methods: The clinical data of patients with adrenal incidentaloma in Chinese PLA General Hospital between January 2008 and December 2016 was retrospectively reviewed and analyzed. All SCS patients were diagnosed based on the current Cushing's syndrome (CS) guidelines and confirmed by histopathology and then treated as study group, and additional patients with non-functional adrenal adenoma (NFA) were enrolled as control group. ROC curve was used to evaluate efficacy of 24 h UFC and 24 h UFC to creatinine ratio (UFCCR), and explore their best cut-off values. Results: There were 161 patients with NFA, of which contained 84 males and 77 females, with a mean age of (51.02±10.49) years old. There were 88 patients with SCS, of which contained 26 males and 62 females, with a mean age of (51.74±10.29) years old. The 24 h UFC and UFCCR levels were significant higher in SCS group than those in NFA group[510 (363, 698) nmol vs 335 (209, 467) nmol for 24 h UFC, and 7.82(4.79, 12.13) ml vs 4.82(2.41, 6.57)ml for UFCCR, both P<0.05]. ROC analysis showed that the optimal cut-off for 24 h UFC was 480 nmol (AUC 0.716, 95% CI: 0.648-0.784, with a sensitivity of 58.0% and a specificity of 79.4%) and the optimal cut-off for UFCCR was 6.84 ml (AUC 0.729, 95% CI: 0.662-0.796, with a sensitivity of 59.1% and a specificity of 78.7%). Conclusions: The recommended cut-off points of 24 h UFC and UFCCR for diagnosing SCS in AI patients were 480 nmol and 6.84 ml, respectively.

[Clinical characteristics of 128 hospitalized patients with syndrome of inappropriate antidiuretics of different etiologies].

Objective: To summarize and analyze the clinical features and etiologies in hospitalized patients with syndrome of inappropriate antidiuretics (SIAD) during the past 25 years. Methods: All data of 128 patients with SIAD admitted to Chinese PLA General Hospital since January 1991 to January 2016 were collected. SIAD was diagnosed based on the 1957 criterion. Results: (1) The most frequent causes of increased inappropriate secretion of vasopressin were malignant tumors, lung diseases (e. g. pneumonia), and central nervous system diseases, in which malignant tumors accounted for 38.28% of the SIAD. (2) During the past 25 years, the proportion of malignant diseases declined from 4/7 to 35.29%, while, the proportion of pulmonary infection increased from 1/7 to 35.29% (P<0.05). (3) The patients with malignant tumors had the lowest serum sodium and serum osmolality among all SIAD patients. (4) CT scan had a high diagnostic value for chest and brain detection. (5) Among three SIAD subjects with unknown reasons at onset, two were diagnosed with small cell lung cancer and one with gastric cancer during follow-up. Conclusion: The etiology of SIAD is complex and it could be attributed to multifarious etiological factors. Malignant tumors account for the largest proportion of all patients, and pulmonary infection was ranked in second place. Cautions on tumors have to be taken when serum sodium of a SIAD patient is below 118.1 mmol/L.

[Clinical value of tumor size in the evaluation of adrenal incidentalomas].

Objective: To investigate the clinical value of tumor size in the evaluation of endocrinological and histological natures regarding adrenal incidentaloma (AI) patients. Methods: A total of 1 941 AI patients who were hospitalized in Department of Endocrinology, Chinese PLA General Hospital between January 1997 and December 2016 were retrospectively reviewed. The demographics of patients, imaging features, functional status and histological results were analyzed. Results: Of 1 941 patients, 984 (50.70%) were males, and 957 (49.30%) were females. The median age was 52 years old. Endocrine evaluation according to the mass size showed that the proportion of non-functional AI and primary aldosteronism (PA) was declined from 84.55% (558/660) to 27.95% (45/161) and from 6.82% (45/660) to 0, respectively. The highest frequency of subclinical Cushing's syndrome (SCS), PA and pheochromocytomas were observed in 2.1-4.0, ≤2.0 and 4.0-6.0 cm group, respectively. Histological results showed that in>6 cm group, the frequency of malignancy were sharply increased. Multivariate logistical regression analysis indicated tumor size had a significant association with the presence of malignancy (OR=1.043, 95% CI: 1.033-1.054, P<0.001). A mass size of 4.0 cm was of great value in distinguishing malignant tumors from the benign ones, with a sensitivity of 89.19%, and a specificity of 69.91%. Conclusion: Mass size was of great value in the endocrinological evaluation, as well as distinguishing malignant tumors from the benign ones in AI patients.

[Surgery versus conservative management for subclinical Cushing's syndrome in adrenal incidentalomas].

Objective: To determine the effect of the surgical and conservative approaches on the metabolic profiles in patients with subclinical Cushing's syndrome (SCS) in adrenal incidentalomas (AI). Methods: A hundred and thirty AI patients with SCS in Department of Endocrinology, PLA General Hospital between January 2008 and December 2016 were studied, surgery was performed in 88 patients (surgical group), and the rest received conservative approach (conservative group). The improvement/worsening of blood pressure, blood glucose, lipid profiles and body weight after a duration of >18 months follow-up were analyzed, respectively. Results: Baseline demographics, clinical characteristics were similar between surgical and conservative groups. In the surgical group, blood pressure, blood glucose, lipid profiles and body weight improved more frequently than that in conservative group (29.69% vs 3.12%, P=0.003; 10.94% vs 3.12%, P=0.262; 7.81% vs 3.12%, P=0.660; 39.06% vs 9.38%, P=0.004, respectively). In conservative group, blood pressure, blood glucose, lipid profiles and body weight worsened more frequently than that in surgical group (28.13% vs 0, P<0.001; 25.0% vs 0, P<0.001; 18.75% vs 0, P=0.003; 40.62% vs 20.31%, P=0.051, respectively). Logistic regression analysis indicated surgical treatment was associated with improvement of blood pressure (OR=10.687, 95%CI: 1.279-89.299) and weight loss (OR=5.541, 95%CI: 1.404-21.872) independently of gender, age, duration of follow-up, serum cortisol level after 1 mg-dexamethasone suppression test and the mass size. Conclusion: In AI patients with SCS, surgery was beneficial in the aspect of metabolic profiles.

[An analysis of four cases of misdiagnosed primary lymphocytic hypophysitis].

To improve the differential diagnosis of sellar region mass, 4 cases with sellar mass and misdiagnosed as lymphocytic hypophysitis (LYH) were reviewed retrospectively.The 4 patients (2 male and 2 female) aged 20-60 years old were all presented with symptoms of headache, polydipsia and polyuria.Biochemical studies confirmed the diagnoses of central diabetes insipidus and hypopituitarism.Head MRI scans showed LYH like image for all the cases, and, thus, high dose methylprednisolone pulse therapy (HDMPT) was applied to the patients.Their symptoms deteriorated and the sellar mass enlarged after a short period of partial improvement.Operations were performed in all the patients.Histology study showed craniopharyngioma with abscess, primary abscess, secondary hypophysitis caused by Wegener's granulomatosis, and germinoma with secondary hypophysitis, respectively.In conclusion, surgery or biopsy is necessary for those who presented with sellar region mass and was suspected to be with LYH, but with poor response or even worse after HDMPT.

[An evaluation of plasma aldosterone-to-active-renin ratio in different postures in combination with aldosterone concentration in the diagnosis of aldosteronoma].

OBJECTIVE: To investigate the diagnostic value of plasma aldosterone-to-active-renin ratio(ARR)in combination with plasma aldosterone concentration(PAC)in the predication of aldosteronoma(APA). METHODS: A total of 85 APA and 155 essential hypertension(EH)patients from January 2012 to December 2014 in Chinese PLA General Hospital were enrolled. The ROC curve was applied to calculate the optimal cut-off points of ARR for APA. RESULTS: (1)The optimal cut-off point of supine ARR was 1 707.4(pmol/L)/(µg·L(-1)·h(-1))[61.64(ng/dl)/(µg·L(-1)·h(-1))] with the sensitivity, specificity and accuracy of 89.41%, 80.65% and 83.75%, respectively. The specificity and accuracy of the diagnostic value for APA increased (89.03% and 87.5% respectively) when supine ARR cut-off point were used in combination with supine PAC over 329.4 pmol/L. (2) The optimal cut-off point of upright ARR was 741.5 (pmol/L)/(µg·L(-1)·h(-1))[26.77(ng/dl)/(µg·L(-1)·h(-1) )]with the sensitivity, specificity and accuracy of 85.88%, 91.61% and 89.58%, respectively. Similarly, the specificity and accuracy greatly improved (94.84% and 91.67%, respectively) when upright ARR were applied together with upright PAC over 323.1 pmol/L. CONCLUSIONS: Both spine and upright ARR can be used in screening for APA. Moreover, the specificity and accuracy could be improved when ARR and PAC were used together both in the supine and upright position.

[Clinical features and outcomes of congenital adrenal hyperplasia with adenomatoid adrenal gland].

Objective: To analyze the clinical features and outcomes of congenital adrenal hyperplasia (CAH) with adenomatoid adrenal gland. Methods: Nineteen patients clinically confirmed as CAH with adenomatoid adrenal gland, from 2008 to 2015 in Deparment of Endocrinology of Chinese PLA General Hospital, were retrospectively analyzed, and the outcomes of the treatment were followed up. Results: Seventy-six patients were clinically confirmed as CAH, from 2008 to 2015 in PLA hospital. Nineteen of them have accompanied with adenomatoid adrenal gland. Of the 19 confirmed cases, 7 were male, and 12 were female. The mean age was (33.3±14.8) years old. Nineteen confirmed cases were consisted of 10 cases of 21-hydroxylase deficiency (OHD), 6 cases of 17α-OHD, and 3 cases of 11ß-OHD. Of the 19 cases, 5 cases presented with adrenal hyperplasia with left side adenomatoid solid lesion, 2 cases presented with adrenal hyperplasia with right side adenomatoid solid lesion, and 8 cases presented with double side adenomatoid solid lesion. The proportion of adrenal hyperplasia with unilateral cystic or calcified changes was 21.1%. Nine of the 19 patients underwent operation or fine needle biopsy. The pathology showed 7 adenomas (21-OHD/17α-OHD 5/2) and 2 myelolipomas (21-OHD/17α-OHD 1/1). Four patients were admitted into hospital because of the incidentaloma, while others because of the clinical symptoms. The average follow-up time was 31 months. CT images were rechecked among 7 patients. After the treatment, 1 patient's tumor shrunk, 4 cases had no recurrence, 1 case's tumor disappeared, and the other one case had no change. Symtoms of eleven followed-up patients relieved. Conclusions: The image of adrenal of CAH with adenomatoid adrenal gland is various. It may occur in each type of CAH presented as unilateral or bilateral, adenoma or myelolipoma.

Estrogenically regulated LRP16 interacts with estrogen receptor alpha and enhances the receptor's transcriptional activity.

Previous studies have shown that leukemia related protein 16 (LRP16) is estrogenically regulated and that it can stimulate the proliferation of MCF-7 breast cancer cells, but there are no data on the mechanism of this pathway. Here, we demonstrate that the LRP16 expression is estrogen dependent in several epithelium-derived tumor cells. In addition, the suppression of the endogenous LRP16 in estrogen receptor alpha (ERalpha)-positive MCF-7 cells not only inhibits cells growth, but also significantly attenuates the cell line's estrogen-responsive proliferation ability. However, ectopic expression of LRP16 in ERalpha-negative MDA-MB-231 cells has no effect on proliferation. These data suggest the involvement of LRP16 in estrogen signaling. We also provide novel evidence by both ectopic expression and small interfering RNA knockdown approaches that LRP16 enhances ERalpha-mediated transcription activity. In stably LRP16-inhibitory MCF-7 cells, the estrogen-induced upregulation of several well-known ERalpha target genes including cyclin D1 and c-myc is obviously impaired. Results from glutathione S-transferase pull-down and coimmunoprecipitation assays revealed that LRP16 physically interacts with ERalpha in a manner that is estrogen independent but is enhanced by estrogen. Furthermore, a mammalian two-hybrid assay indicated that the binding region of LRP16 localizes to the A/B activation function 1 domain of ERalpha. Taken together, these results present new data supporting a role for estrogenically regulated LRP16 as an ERalpha coactivator, providing a positive feedback regulatory loop for ERalpha signal transduction.