Estrogen receptor beta expression in prostate adenocarcinoma

Promising Therapeutic Impact of a Selective Estrogen Receptor Downregulator, Fulvestrant, as Demonstrated In Vitro upon Low-Grade Serous Ovarian Carcinoma Cell Lines

Few studies have reported hormonal agent use in the treatment of low-grade serous ovarian carcinomas (LGSOCs), which are chemoresistant. Considering the need for novel effective therapies, we investigated the hormone receptor expression and hormonal inhibition efficacy in LGSOCs. Using immunohistochemistry, we assessed the estrogen receptor (ER) expression status in 33 cases of histologically confirmed serous ovarian tumors, including 10, 11, and 12 cases of LGSOCs, serous borderline tumors (SBTs), and serous cystadenomas (SCAs), respectively. The genetic background reported in our previous study was used in the current study. MPSC1 cells, which were established from LGSOCs, were used in cell proliferation assays. We observed a higher ER expression in LGSOCs and SBTs than in SCAs (70%, 81%, and 50%, respectively). Thus, LGSOCs and SBTs exhibit higher ER expression than SCAs. Moreover, the PIK3CA mutation positively correlated with ER expression in LGSOCs (p = 0.0113). MPSC1 cells showed low ER expression on Western blotting. MPSC1 cell proliferation was significantly inhibited by fulvestrant (a selective ER downregulator). The activation of ER and PI3K/AKT signaling pathways may play an important role in LGSOC carcinogenesis. ER downregulation with fulvestrant or combination therapy with PI3K inhibitors is a possible novel treatment for patients with LGSOCs.

ZFHX3 is indispensable for ERβ to inhibit cell proliferation via MYC downregulation in prostate cancer cells

Both estrogen receptor 2 (ESR2, also known as estrogen receptor beta (ERβ)) and the zinc-finger homeobox 3 (ZFHX3, also known as ATBF1 for AT motif-binding factor 1) modulate prostate development and suppress prostatic tumorigenesis in mice. ZFHX3 is integral to proper functions of ESR1 (i.e., estrogen receptor alpha (ERα)), which belongs to the same family of proteins as ESR2, but is hardly expressed in prostate epithelial cells. It is not clear how ZFHX3 suppresses prostatic tumorigenesis. In this study, we investigated whether ZFHX3 and ERβ functionally interact with each other in the suppression of prostatic tumorigenesis. In two androgen receptor (AR)-positive prostate cancer cell lines, C4-2B and LNCaP, we first validated ERβ’s tumor suppressor activity indicated by the inhibition of cell proliferation and repression of MYC expression. We found that loss of ZFHX3 increased cell proliferation and MYC expression, and downregulation of MYC was necessary for ZFHX3 to inhibit cell proliferation in the same cell lines. Importantly, loss of ZFHX3 prevented ERβ from suppressing cell proliferation and repressing MYC transcription. Biochemically, ERβ and ZFHX3 physically interacted with each other and they both occupied the same region of the common MYC promoter, even though ZFHX3 also bound to another region of the MYC promoter. Higher levels of ZFHX3 and ERβ in human prostate cancer tissue samples correlated with better patient survival. These findings establish MYC repression as a mechanism for ZFHX3’s tumor suppressor activity and ZFHX3 as an indispensable factor for ERβ’s tumor suppressor activity in prostate cancer cells. Our data also suggest that intact ZFHX3 function is required for using ERβ-selective agonists to effectively treat prostate cancer.

Association between decreased expression of estrogen receptor alpha, androgen receptor and phosphatase and tensin homolog immunoexpression in the canine prostate

ABSTRACT: Canine prostate gland is a hormonal dependent organ and its imbalance of estrogen and androgen receptor expressions are directly associated with the development of different diseases. Due to the lack of information regarding the behavior of the aforementioned receptors in canine prostate cancer (PC), this study aimed to identify estrogen receptor alpha (ERα), androgen receptor (AR), Ki67 and phosphatase and tensin homolog (PTEN) protein expressions in canine PC by immunohistochemistry. We found nuclear expression of ERα and AR in the epithelial cells of normal canine samples and a loss of protein expression in PC samples. Normal samples showed Ki67 expression in a few basal cells and the PC samples showed the highest mean of positive cells (253.1). Canine prostate cancer showed a high proliferative index, which was associated with independence of hormonal actuation. PTEN showed positive nuclear and cytoplasmic expression in normal canine samples and a loss in PC. Loss of ERα, AR and PTEN indicated that canine PC exhibits the same immunohistochemical phenotype as in human patients with PC resistant to hormonal therapy. Therefore, canine PC should be considered as a model to study human PC resistant to hormonal therapy.

In Vivo Study of the Effects of ERβ on Apoptosis and Proliferation of Hormone-Independent Prostate Cancer Cell Lines PC-3M

OBJECTIVE

To evaluate the in vivo therapeutic effects of attenuated Salmonella carrying PCDNA3.1-ERβ plasmid in hormone-independent prostatic cancer in nude mice and to clarify the mechanism by which estrogen receptor β (ERβ) induces apoptosis and proliferation in prostatic cancer cells in mice.

METHODS

The orthotopic prostatic cancer models of mice were randomly divided as follows: MOCK group, treated with PBS, PQ group, treated with attenuated Salmonella alone, PQ-PCDNA3.1 group, treated with attenuated Salmonella carrying PCDNA3.1 plasmid, and PQ-PCDNA3.1-ERβ group, treated with the attenuated Salmonella carrying PCDNA3.1-ERβ plasmid. Then, 10 μl of the plasmid-containing solution, comprising 1 × 107 cfu of the bacteria, was administered via intranasal delivery to each group except the MOCK group. The experimental methods included flow cytometry and terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) assay, immunohistochemistry, and western blotting.

RESULTS

Compared with the MOCK, PQ, and PQ-PCDNA3.1 groups, the weights of tumors in the PQ-PCDNA3.1-ERβ group were significantly reduced. The results of flow cytometry and TUNEL assay revealed that the number of apoptotic cells in the PQ-PCDNA3.1-ERβ group significantly increased. Compared with PQ-PCDNA3.1 group, the protein expression levels of ERβ, Bad, p-caspase 9, p-caspase 3, and cleaved PARP in the PQ-PCDNA3.1-ERβ group were significantly increased, while the expression levels of Akt, p-Akt, and Bcl-xl were decreased (P < 0.05).

CONCLUSION

The attenuated Salmonella carrying PCDNA3.1-ERβ plasmid could inhibit the growth of orthotopic prostatic cancer in mice by increasing the expression of ERβ.

Role of co-expression of estrogen receptor beta and Ki67 in prostate adenocarcinoma

Purpose

To evaluate the expression of estrogen receptor (ER)-beta and Ki67 in prostate cancer and study their relationship.

Materials and Methods

We analyzed 101 cases of prostate adenocarcinoma diagnosed from January 2011 to June 2015 in 100 patients. Immunohistochemical staining of ER-beta and Ki67 was analyzed according to Gleason score categorized into prognostic groups of 1 to 5. Double-immunofluorescent staining of ER-beta and Ki67 was performed in a total of 20 cases to study the co-expression and the relationship between these markers within the same tumor.

Results

A total of 53 of 101 cases (52.5%) were positive for ER-beta expression. There was a positive correlation whereby a high percentage of ER-beta expression was seen in the higher prognostic groups (groups 4 and 5; p=0.007). High Ki67 expression was observed in the higher prognostic group, whereas low Ki67 or negative expression was found in the lower prognostic group (p<0.001). The majority of cases evaluated with double-immunofluorescent staining (14/20) showed co-expression of ER-beta and Ki67 at the individual cell level.

Conclusions

ER-beta and Ki67 are independent tumor markers in high prognostic groups. Hence, co-expression of ER-beta and Ki67 indicates a more aggressive tumor with a poorer prognosis.

Increased Expression of ALDH1A1 in Prostate Cancer is Correlated With Tumor Aggressiveness: A Tissue Microarray Study of Iranian Patients

INTRODUCTION

Subpopulations of prostate cancer (PCa) cells expressing putative stem cell markers possess the ability to promote tumor growth, maintenance, and progression. This study aimed to evaluate the expression patterns and clinical significance of putative stem cell marker aldehyde dehydrogenase 1 A1 (ALDH1A1) in prostate tumor tissues.

MATERIALS AND METHODS

ALDH1A1 expression was examined in a well-defined series of prostate tissues, including 105 (68%) samples of PCa, 21 (13%) samples of high-grade prostatic intraepithelial neoplasia, and 31 (19%) samples of benign prostate hyperplasia, which were embedded in tissue microarray blocks. The correlation of ALDH1A1 expression with clinicopathologic parameters was also assessed.

RESULTS

There was a significant difference between the expression level of ALDH1A1 in PCa compared with the high-grade prostatic intraepithelial neoplasia and benign prostate hyperplasia samples (P<0.001). PCa cells expressing ALDH1A1 were more often seen in samples with advanced Gleason score (P=0.05) and high serum prostate specific antigen level (P=0.02). In addition, a positive correlation was found between ALDH1A1 expression and primary tumor stage and regional lymph node involvement (P=0.04 and 0.03, respectively).

CONCLUSIONS

The significant association between ALDH1A1 expressions with Gleason score indicates the potential role of this protein in PCa tumorigenesis and aggressive behavior; therefore, this cancer stem cell marker can be used as a promising candidate for targeted therapy of PCa, especially those with high Gleason score.

Involvement of estrogen receptor β in androgen receptor-induced growth inhibition in prostate cancer PC-3 cells

Previous studies have suggested that changes in sex hormone receptor expression may be associated with the initiation and progression of prostate cancer (PCa). Therefore, the present study aimed to investigate the association and possible pathways between two sex hormone receptors and PCa by measuring the expression levels of the androgen receptor (AR) and the estrogen receptor subtypes alpha (ERα) and beta (ERβ) in prostatic cancer PC-3 cell lines. The pcDNA3.1-hERβ plasmid was transfected into PC-3 cell lines. The expression levels of AR, ERα and ERβ were detected at the mRNA level by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR). The results demonstrated that the expression levels of AR, ERβ and ERα were downregulated to different degrees: ERβ test group vs. PC-3 cell group (P=0.000; 95% confidence interval: 0.9803-1.6331). ERβ and AR expression was detected continuously in the PC-3 cells, but the expression of ERα was not. AR expression levels exhibited an upward trend whilst the expression of ERβ demonstrated a marked downward trend. There is a correlation between the expression levels of ERβ and the incidence of PCa, and ERβ may inhibit the growth of PC-3 cell lines by regulating the expression levels of AR. ERβ may provide a novel target for PCa therapies.

27-hydroxycholesterol: A novel player in molecular carcinogenesis of breast and prostate cancer

Several studies have suggested an etiological role for hypercholesterolemia in the pathogenesis of breast cancer and prostate cancer (PCa). However, the molecular mechanisms that underlie and mediate the hypercholesterolemia-fostered increased risk for breast cancer and PCa are yet to be determined. The discovery that the most abundant cholesterol oxidized metabolite in the plasma, 27 hydroxycholesterol (27-OHC), is a selective estrogen receptor modulator (SERM) and an agonist of Liver X receptors (LXR) partially fills the void in our understanding and knowledge of the mechanisms that may link hypercholesterolemia to development and progression of breast cancer and PCa. The wide spectrum and repertoire of SERM and LXR-dependent effects of 27-OHC in the context of all facets and aspects of breast cancer and prostate cancer biology are reviewed in this manuscript in a very comprehensive manner. This review highlights recent findings pertaining to the role of 27-OHC in breast cancer and PCa and delineates the signaling mechanisms involved in the governing of different facets of tumor biology, that include tumor cell proliferation, epithelial-mesenchymal transition (EMT), as well as tumor cell invasion, migration, and metastasis. We also discuss the limitations of contemporary studies and lack of our comprehension of the entire gamut of effects exerted by 27-OHC that may be relevant to the pathogenesis of breast cancer and PCa. We unveil and propose potential future directions of research that may further our understanding of the role of 27-OHC in breast cancer and PCa and help design therapeutic interventions against endocrine therapy-resistant breast cancer and PCa.

Profile of cell proliferation and apoptosis activated by the intrinsic and extrinsic pathways in the prostate of aging rats

BACKGROUND

Estrogens acting through the receptors ERα and ERβ participate in prostate normal growth and cancer. ERβ is highly expressed in the prostate epithelium, playing pro-apoptotic, anti-proliferative, and pro-differentiation roles. Apoptosis is activated by the intrinsic pathway after castration and by the extrinsic pathway after ERβ agonist treatment. This differential activation of apoptotic pathways is important since a major problem in the treatment of prostate cancer is the recurrence of tumors after androgen withdrawal. However, a comprehensive study about the pattern of apoptosis in the aging prostate is lacking, a knowledge gap that we aimed to address herein.

METHODS

Cellular age-related proliferative and apoptotic profiles of prostate tissue obtained from aging Wistar rats were evaluated. Cell death (caspase-3, -8, -9, TNFα) was assessed by immunohistochemistry, immunofluorescence, and TUNEL. Cell proliferation (MCM7) and cell survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) were determined by immunohistochemistry.

RESULTS

As the rats aged, the number of proliferating cells gradually reduced in the normal epithelium of all prostate lobes, while increasing in focal areas of intraepithelial proliferation. Interestingly, in areas of intraepithelial proliferation, we observed a reduction in the number of cells positive for caspase-3, -8, and -9. Regardless the animal's age, few prostate epithelial cells were positive for caspase-3, caspase-9, and TUNEL. In contrast, a progressive increase was seen in the positivity for caspase-8, especially in the atrophic epithelium of ventral prostate, which coincided with a reduction in TNFα immunoreaction. However, morphology of most caspase-8 positive cells suggests that they were not apoptotic. We also found reduced ERβ expression in the same areas. Possibly, low levels of the pro-apoptotic inductors TNFα and ERβ direct caspase-8 activity to an alternative pro-survival role in the atrophic epithelium. This hypothesis is supported by the increased expression of the key survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) in these areas.

CONCLUSIONS

Our findings reveal that, as the animals age, there is an increase of proliferation in restricted areas of the prostate epithelium, and a concomitant reduction of the apoptosis rate with an increase in cell survival induced by caspase-8, indicating a focused and spontaneous disruption of tissue homeostasis.

Dual action of high estradiol doses on MNU-induced prostate neoplasms in a rodent model with high serum testosterone: Protective effect and emergence of unstable epithelial microenvironment

BACKGROUND

Estrogens are critical players in prostate growth and disease. Estrogen therapy has been the standard treatment for advanced prostate cancer for several decades; however, it has currently been replaced by alternative anti-androgenic therapies. Additionally, studies of its action on prostate biology, resulting from an association between carcinogens and estrogen, at different stages of life are scarce or inconclusive about its protective and beneficial role on induced-carcinogenesis. Thus, the aim of this study was to determine whether estradiol exerts a protective and/or stimulatory role on N-methyl-N-nitrosurea-induced prostate neoplasms.

METHODS

We adopted a rodent model that has been used to study induced-prostate carcinogenesis: the Mongolian gerbil. We investigated the occurrence of neoplasms, karyometric patterns, androgen and estrogen receptors, basal cells, and global methylation status in ventral and dorsolateral prostate tissues.

RESULTS

Histopathological analysis showed that estrogen was able to slow tumor growth in both lobes after prolonged treatment. However, a true neoplastic regression was observed only in the dorsolateral prostate. In addition to the protective effects against neoplastic progression, estrogen treatment resulted in an epithelium that exhibited features distinctive from a normal prostate, including increased androgen-insensitive basal cells, high androgens and estrogen receptor positivity, and changes in DNA methylation patterns.

CONCLUSIONS

Estrogen was able to slow tumor growth, but the epithelium exhibited features distinct from a normal prostatic epithelium, and this unstable microenvironment could trigger lesion recurrence over time.

Comprehensive assessment of estrogen receptor beta antibodies in cancer cell line models and tissue reveals critical limitations in reagent specificity

Estrogen Receptor-β (ERβ) has been implicated in many cancers. In prostate and breast cancer its function is controversial, but genetic studies implicate a role in cancer progression. Much of the confusion around ERβ stems from antibodies that are inadequately validated, yet have become standard tools for deciphering its role. Using an ERβ-inducible cell system we assessed commonly utilized ERβ antibodies and show that one of the most commonly used antibodies, NCL-ER-BETA, is non-specific for ERβ. Other antibodies have limited ERβ specificity or are only specific in one experimental modality. ERβ is commonly studied in MCF-7 (breast) and LNCaP (prostate) cancer cell lines, but we found no ERβ expression in either, using validated antibodies and independent mass spectrometry-based approaches. Our findings question conclusions made about ERβ using the NCL-ER-BETA antibody, or LNCaP and MCF-7 cell lines. We describe robust reagents, which detect ERβ across multiple experimental approaches and in clinical samples.

Expression of estrogen and progesterone receptors across human malignancies: new therapeutic opportunities

Estrogen and progesterone receptors (ERs and PRs) are known for their prognostic as well as treatment predictive value in breast cancer. Although these receptors are differentially expressed in some other malignancies, and likely participate in the biology of those cancer types, the relevance to outcome and therapy is not well established. The use of ER as a highly effective therapeutic target in oncology was pioneered in breast cancer, and the lessons learned from its success could potentially benefit patients with several other malignancies in which hormone receptors are highly expressed. Indeed, there are several potent drugs available that target hormone receptors. These agents show incontrovertible evidence of benefit in patients with hormone receptor-positive breast cancer. It is conceivable that these drugs may have salutary effects in a variety of cancers other than those originating in the breast, based on the overexpression of hormone receptors in some patients, and the preclinical and clinical reports showing responses to these drugs in diverse cancers, albeit in small series or anecdotally. We therefore undertook a literature review in order to summarize the current data regarding the biologic and clinical implications of expression of estrogen and progesterone receptors in various malignancies and the possibilities for deployment of hormone manipulation beyond breast cancer.

Changes in Estrogen Receptor ERβ (ESR2) Expression without Changes in the Estradiol Levels in the Prostate of Aging Rats

Although the prostate is androgen-dependent, it is also influenced by estrogens, which act via the estrogen receptors ERα and ERβ. In the prostate, ERβ is highly expressed in the epithelium and appears to participate in the regulation of cell proliferation, apoptosis and differentiation. Evidence shows that ERβ is decreased in malignant prostate, suggesting that it plays an important role in protecting this tissue. Despite the relationship between reductions in ERβ and abnormal growth of the gland, little is known about the age-dependent variation of this receptor. Therefore, we aimed to investigate ERβ expression in the prostatic lobes of aging Wistar rats (3 to 24 months). Histopathological alterations, including hyperplasia, intraluminal concretions, nuclear atypia and prostate intraepithelial neoplasias (PIN), were observed in the prostates of aging rats. Epithelial proliferation led to cribriform architecture in some acini, especially in the ventral prostate (VP). In the VP, areas of epithelial atrophy were also observed. Furthermore, in the lateral prostate, there was frequent prostatitis. Immunohistochemistry revealed that the expression of ERβ is reduced in specific areas related to PIN, atrophic abnormalities and cellular atypia in the prostate epithelium of senile rats. Corroborating the involvement of the receptor with proliferative activity, the punctual reduction in ERβ paralleled the increase in cell proliferation especially in areas of PIN and nuclear atypies. The decrease in ERβ reactivity occurred in a hormonal milieu characterized by a constant concentration of estradiol and decreased plasmatic and tissue DHT. This paper is a pioneering study that reveals focal ERβ reduction in the prostate of aging rats and indicates a potential disorder in the ERβ pathway. These data corroborate previous data from humans and dogs that silencing of this receptor may be associated with premalignant or malignant conditions in the prostate.

Expression of estrogen receptor β and Ki 67 in benign & malignant human prostate lesions by immunohistochemistry

Estrogen regulates the growth of prostate through two receptors Estrogen receptor α & β of which ERβ is proposed to be antiproliferative. There is a wide variation in the results of various studies regarding the localisation, level of expression of ERβ in benign & malignant lesions of prostate and its relation to the grade of tumor emphasizing the need for additional studies to standardize the distribution of this receptor in prostate. This was a prospective study conducted in Department of Pathology, UCMS, Delhi, evaluating ERβ & Ki 67 immunoexpression in 60 cases of benign and malignant lesions of prostate (30 each). Tissue for study included prostatic core biopsy and TURP chips. After histomorphological diagnosis, immunohistochemical staining was performed using a monoclonal antibody. Nuclear expression of ERβ & Ki67 was evaluated and compared between the two study groups (benign & malignant lesions) using Pearson chi square test. ERβ was predominantly localized to nuclei of secretory epithelium of prostatic glands. Expression of ERβ was higher in benign glands compared to carcinoma. However, majority of carcinomas retained ERβ expression though at much lower levels. Expression of Ki 67 was higher in carcinoma than benign hyperplasia. There was no correlation between the ERβ status, Ki 67 expression & grade of tumor. Expression of ERβ is downregulated in carcinoma compared to benign hyperplasia and is consistent with its chemopreventive role in prostate. It might have a therapeutic implication as agonists' targeting this receptor could be a part of treatment protocol for those patients of carcinoma who retain this receptor at significant levels.

Estrogen receptor beta in prostate cancer: friend or foe?

Prostate cancer is the commonest, non-cutaneous cancer in men. At present, there is no cure for the advanced, castration-resistant form of the disease. Estrogen has been shown to be important in prostate carcinogenesis, with evidence resulting from epidemiological, cancer cell line, human tissue and animal studies. The prostate expresses both estrogen receptor alpha (ERA) and estrogen receptor beta (ERB). Most evidence suggests that ERA mediates the harmful effects of estrogen in the prostate, whereas ERB is tumour suppressive, but trials of ERB-selective agents have not translated into improved clinical outcomes. The role of ERB in the prostate remains unclear and there is increasing evidence that isoforms of ERB may be oncogenic. Detailed study of ERB and ERB isoforms in the prostate is required to establish their cell-specific roles, in order to determine if therapies can be directed towards ERB-dependent pathways. In this review, we summarise evidence on the role of ERB in prostate cancer and highlight areas for future research.

Tumor attributes predicting cutaneous metastatic destiny: a report of two interesting cases

Cutaneous metastases are the result of complex interaction between the tumor cells ("seed") and the host environment ("soil"). Metastases to the skin can be an early sign of internal malignancy or represent recurrence of the primary tumor and portends a poorer prognosis. Invasion and metastasis are the hallmarks of on cogenesis. Skin is the largest organ in the body, but the incidence of metastases is low. With advances in molecular biology, factors responsible for the initiation and perpetuation of metastatic tumor cells at distant sites are being elucidated. The concept of "pre-metastatic niche" and interaction between various chemokines has given a new outlook in understanding the organ specificity of metastatic tumor cells. We present two cases of cutaneous metastases with interesting clinical findings correlating with its biologic subtypes.

Factors associated with the survival of prostate cancer patients with rectal involvement

BACKGROUND

Prostate cancer patients with rectal involvement are rare, and the factors associated with the survival of these patients are yet to be elucidated.

PATIENTS AND METHODS

We collected data on patients who were admitted to our hospital for prostate cancer in the last thirteen years and of those in studies in the literature. The associations of clinical characteristics with survival were evaluated using Cox regression models.

RESULTS

This study included 94 patients (5 admitted to our hospital and 89 from studies in the literature) of prostate cancer with rectal involvement. 11 patients in the group of synchronous rectal involvement at first cancer diagnosis (n = 58) and 23 patients in the group of metachronous diagnosis of rectal involvement (n = 29) died at the latest follow up. The estimated overall survival rate (% ± SE) at 1, 3, and 5 years were 68.3 ± 5.3%, 54.4 ± 7.2%, and 38.1 ± 11.1%, respectively. In the Cox univariate analysis, Asian prostate cancer (p = 0.001) was associated with better survival, while rectal bleeding (p = 0.043), metachronous presentation of development of rectal involvement (p = 0.000), prior hormonal therapy (p = 0.000) and extrarectal metastases (p = 0.054) were associated with poor survival. In multivariate analysis, prior hormone therapy (HR = 14.540, p = 0.000) and rectal bleeding (HR = 2.195, p = 0.041) retained independent poor prognostic values. There were 13 patients survived for more than 3 years, the longest survival time was 96 months. Total pelvic extenteration (TPE) combined with hormonal therapy in 12 hormone-untreated prostate cancer give us six of thirteen long-term survivors for more than 3 years in this series.

CONCLUSIONS

Our findings suggest that rectal involvement does not necessarily predict a worse outcome when presenting as a previously hormone-untreated disease and that the prognosis was worse when presenting as a hormone relapsed disease. Prior hormone therapy and rectal bleeding were associated independently with a significantly poor overall survival in prostate cancer patients with rectal involvement. TPE combined with hormonal therapy appears to confer better overall survival in hormonally untreated patients.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1604504118106105.

Expression of prostate stem cell antigen (PSCA) in prostate cancer: a tissue microarray study of Iranian patients

Proteins expressed in prostate cancer, including prostate stem cell antigen (PSCA), have been investigated as biomarkers for diagnosis and therapy of prostate cancer. Immunohistochemical analysis of PSCA expression was performed on tissue microarrays of 185 paraffin-embedded tissues of Iranian patients, including 114 prostate cancers (PCa), 21 High Grade Prostatic Intraepithelial Neoplasias (HGPIN) and 50 samples of benign prostate tissue. The level of PSCA expression was compared between benign tissues, HGPIN and PCa. Then the correlations of PSCA expression with clinicopathologic parameters were assessed in PCa. The PSCA expression was detected in the membrane and cytoplasm of epithelial secretory cells in normal prostate tissues, HGPIN and PCa with a variety of intensities. The intensity of PSCA staining was significantly increased in the PCa group as compared with HGPIN and benign prostate tissues (P-value<0.05). Moreover, the level of PSCA expression was increased with higher Gleason score of PCa (P-value=0.036). The data presented here revealed that expression of PSCA as a cell surface marker increased from benign prostate tissues (BPH) and HGPIN to PCa, and its expression in PCa was positively associated with poor cell differentiation, suggesting that PSCA could be considered as a valuable target for diagnosis and therapy of PCa.

Steroid hormone receptor expression in ovarian cancer: progesterone receptor B as prognostic marker for patient survival

BACKGROUND

There is partially conflicting evidence on the influence of the steroid hormones estrogen (E) and progesterone (P) on the development of ovarian cancer (OC). The aim of this study was to assess the expression of the receptor isoforms ER-α/-β and PR-A/-B in OC tissue and to analyze its impact on clinical and pathological features and patient outcome.

METHODS

155 OC patients were included who had been diagnosed and treated between 1990 and 2002. Patient characteristics, histology and follow-up data were available. ER-α/-β and PR-A/-B expression were determined by immunohistochemistry.

RESULTS

OC tissue was positive for ER-α/-β in 31.4% and 60.1% and PR-A/-B in 36.2% and 33.8%, respectively. We identified significant differences in ER-β expression related to the histological subtype (p=0.041), stage (p=0.002) and grade (p=0.011) as well as PR-A and tumor stage (p=0.03). Interestingly, median receptor expression for ER-α and PR-A/-B was significantly higher in G1 vs. G2 OC. Kaplan Meier analysis revealed a good prognosis for ER-α positive (p=0.039) and PR-B positive (p<0.001) OC. In contrast, ER-β negative OC had a favorable outcome (p=0.049). Besides tumor grade and stage, Cox-regression analysis showed PR-B to be an independent prognostic marker for patient survival (p=0.009, 95% CI 0.251-0.823, HR 0.455).

CONCLUSION

ER-α/-β and PR-A/-B are frequently expressed in OC with a certain variability relating to histological subtype, grade and stage. Univariate analysis indicated a favorable outcome for ER-α positive and PR-B positive OC, while multivariate analysis showed PR-B to be the only independent prognostic marker for patient survival. In conclusion, ER and PR receptors may be useful targets for a more individualized OC therapy.

Prostate carcinoma metastatic to the skin as an extrammamary Paget's disease

AIM

The current paper describes a case of prostatic adenocarcinoma metastatic to the skin presenting as an extrammamary Paget's disease, a very rare and poorly characterised morphological entity. We report a case of prostatic carcinoma metastatic to skin showing a pattern of extramammary Paget's disease which has not been clearly illustrated in the literature Case presentation: A 63 year-old man with prostatic adenocarcinoma developed cutaneous metastases after 16 years. The inguinal metastases were sessile and 'keratotic.' The tumour displayed solid, glandular areas as well as a polypoid region suggestive of extramammary Paget's disease were identified.

DISCUSSION AND CONCLUSIONS

We review the diagnostic criteria that have led to the correct histopathological diagnosis in this case. A differential diagnosis of the pagetoid spread in the skin and various forms of cutaneous metastases determined by a prostatic adenocarcinoma as well as the role of immunohistochemistry in establishing the prostatic origin are presented in the context of this case. Although, morphologically the cells presented in the skin deposits were not characteristic for adenocarcinoma of prostate, immunohistochemistry for PSA and PSAP suggested a prostatic origin.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1395450057455276.

The impact of cow's milk-mediated mTORC1-signaling in the initiation and progression of prostate cancer

Prostate cancer (PCa) is dependent on androgen receptor signaling and aberrations of the PI3K-Akt-mTORC1 pathway mediating excessive and sustained growth signaling. The nutrient-sensitive kinase mTORC1 is upregulated in nearly 100% of advanced human PCas. Oncogenic mTORC1 signaling activates key subsets of mRNAs that cooperate in distinct steps of PCa initiation and progression. Epidemiological evidence points to increased dairy protein consumption as a major dietary risk factor for the development of PCa. mTORC1 is a master regulator of protein synthesis, lipid synthesis and autophagy pathways that couple nutrient sensing to cell growth and cancer. This review provides evidence that PCa initiation and progression are promoted by cow´s milk, but not human milk, stimulation of mTORC1 signaling. Mammalian milk is presented as an endocrine signaling system, which activates mTORC1, promotes cell growth and proliferation and suppresses autophagy. Naturally, milk-mediated mTORC1 signaling is restricted only to the postnatal growth phase of mammals. However, persistent consumption of cow´s milk proteins in humans provide highly insulinotropic branched-chain amino acids (BCAAs) provided by milk´s fast hydrolysable whey proteins, which elevate postprandial plasma insulin levels, and increase hepatic IGF-1 plasma concentrations by casein-derived amino acids. BCAAs, insulin and IGF-1 are pivotal activating signals of mTORC1. Increased cow´s milk protein-mediated mTORC1 signaling along with constant exposure to commercial cow´s milk estrogens derived from pregnant cows may explain the observed association between high dairy consumption and increased risk of PCa in Westernized societies. As well-balanced mTORC1-signaling plays an important role in appropriate prostate morphogenesis and differentiation, exaggerated mTORC1-signaling by high cow´s milk consumption predominantly during critical growth phases of prostate development and differentiation may exert long-term adverse effects on prostate health. Attenuation of mTORC1 signaling by contemporary Paleolithic diets and restriction of dairy protein intake, especially during mTORC1-dependent phases of prostate development and differentiation, may offer protection from the most common dairy-promoted cancer in men of Western societies.

Synthesis and biological evaluation of two agents for imaging estrogen receptor β by positron emission tomography: challenges in PET imaging of a low abundance target

INTRODUCTION

Independent measurement of the levels of both the estrogen receptors, ERα and ERβ, in breast cancer could improve prediction of benefit from endocrine therapies. While ERα levels can be measured by positron emission tomography (PET) using 16α-[(18)F]fluoroestradiol (FES), no effective agent for imaging ERβ by PET has yet been reported.

METHODS

We have prepared the fluorine-18 labeled form of 8β-(2-fluoroethyl)estradiol (8BFEE(2)), an analog of an ERβ-selective steroidal estrogen, 8β-vinylestradiol; efficient incorporation of fluorine-18 was achieved, but required very vigorous conditions. We have examined the biodistribution of this compound, as well as of Br-041, an analog of a known non-steroidal ERβ-selective ligand (ERB-041), labeled with bromine-76. Studies were done in immature female rodents, with various pharmacological and endocrine perturbations to assess ERβ selectivity of uptake.

RESULTS

Little evidence of ERβ-mediated uptake was observed with either [(18)F]8BFEE(2) or [(76)Br]Br-041. Attempts to increase the ERβ content of target tissues were not effective and failed to improve biodistribution selectivity.

CONCLUSIONS

Because on an absolute basis level, ERβ levels are low in all target tissues, these studies have highlighted the need to develop improved in vivo models for evaluating ERβ-selective radiopharmaceuticals for use in PET imaging. Genetically engineered breast cancer cells that are being developed to express either ERα or ERβ in a regulated manner, grown as xenografts in immune-compromised mice, could prove useful for future studies to develop ER subtype-selective radiopharmaceuticals.