Cancer risk in hyperprolactinemia patients: a population-based cohort study

Prolactin receptor signaling induces acquisition of chemoresistance and reduces clonogenicity in acute myeloid leukemia

BACKGROUND

Development of precision medicine requires the identification of easily detectable and druggable biomarkers. Despite recent targeted drug approvals, prognosis of acute myeloid leukemia (AML) patients needs to be greatly improved, as relapse and refractory disease are still difficult to manage. Thus, new therapeutic approaches are needed. Based on in silico-generated preliminary data and the literature, the role of the prolactin (PRL)-mediated signaling was interrogated in AML.

METHODS

Protein expression and cell viability were determined by flow cytometry. Repopulation capacity was studied in murine xenotransplantation assays. Gene expression was measured by qPCR and luciferase-reporters. SA-β-Gal staining was used as a senescence marker.

RESULTS

The prolactin receptor (PRLR) was upregulated in AML cells, as compared to their healthy counterpart. The genetic and molecular inhibition of this receptor reduced the colony-forming potential. Disruption of the PRLR signaling, either using a mutant PRL or a dominant-negative isoform of PRLR, reduced the leukemia burden in vivo, in xenotransplantation assays. The expression levels of PRLR directly correlated with resistance to cytarabine. Indeed, acquired cytarabine resistance was accompanied with the induction of PRLR surface expression. The signaling associated to PRLR in AML was mainly mediated by Stat5, in contrast to the residual function of Stat3. In concordance, Stat5 mRNA was significantly overexpressed at mRNA levels in relapse AML samples. A senescence-like phenotype, measured by SA-β-gal staining, was induced upon enforced expression of PRLR in AML cells, partially dependent on ATR. Similar to the previously described chemoresistance-induced senescence in AML, no cell cycle arrest was observed. Additionally, the therapeutic potential of PRLR in AML was genetically validated.

CONCLUSIONS

These results support the role of PRLR as a therapeutic target for AML and the further development of drug discovery programs searching for specific PRLR inhibitors.

Hyperprolactinaemia is common in Chinese premenopausal women with breast diseases

Purpose: Hyperprolactinaemia has been proposed to play a role in breast lesions pathophysiology. Thus far, controversial results have been reported for the relationship between hyperprolactinaemia and breast lesions. Moreover, the prevalence of hyperprolactinaemia in a population with breast lesions is scarcely reported. We aimed to investigate the prevalence of hyperprolactinaemia in Chinese premenopausal women with breast diseases, and explore the associations between hyperprolactinaemia with different clinical characteristics. Methods: This was a retrospective cross-sectional study performed in the department of breast surgery of Qilu hospital of Shandong University. Overall, 1,461 female patients who underwent the serum prolactin (PRL) level assay before breast surgery from January 2019 to December 2020 were included. Patients were divided into two groups: before and after menopause. Data were analyzed using SPSS 18.0 software. Results: The results showed an elevated PRL level in 376 of the 1,461 female patients with breast lesions (25.74%). Furthermore, the proportion of hyperprolactinemia among premenopausal patients with breast disease (35.75%, 340/951) was significantly higher than among postmenopausal patients with breast disease (7.06%, 36/510). In premenopausal patients, the proportion of patients with hyperprolactinaemia and the mean serum PRL level were significantly higher in those diagnosed with fibroepithelial tumours (FETs) and in younger patients (aged < 35 years) than in those with non-neoplastic lesions and in those aged ≥ 35 years (both p < 0.05). Especially, the prolactin level exhibited steady ascending tendency for positive correlation with FET. Conclusion: Hyperprolactinaemia is prevalent in Chinese premenopausal patients with breast diseases, especially in those with FETs, which implies a potential association, to some extent, between the PRL levels in various breast diseases.

Association between schizophrenia and prostate cancer risk: Results from a pool of cohort studies and Mendelian randomization analysis

BACKGROUND

Observational studies analyzing the risk of prostate cancer in schizophrenia patients have generated mixed results. We performed a meta-analysis and a Mendelian randomization (MR) analysis to evaluate the relationship and causality between schizophrenia and the risk of prostate cancer.

METHODS

A comprehensive and systematic search of cohort studies was conducted, and a random-effects model meta-analysis was performed to calculate the standardized incidence ratios (SIRs) for prostate cancer incidence among schizophrenia patients versus the general population. To investigate the correlation between genetically-predicted schizophrenia and prostate cancer risk, we used summary statistics from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium (61,106 controls and 79,148 cases), and 75 schizophrenia-associated single nucleotide polymorphisms (SNP) from European descent as the instrumental variable.

RESULTS

In the meta-analysis of 13 cohort studies with 218,076 men involved, a decreased risk of prostate cancer was observed among schizophrenia patients [SIR 0.610; 95% confidence interval (CI) 0.500-0.740; p < 0.001] with significant heterogeneity (I² = 83.3%; p < 0.001). However, MR analysis did not sustain the link between genetically-predicted schizophrenia and prostate cancer [odds ratio (OR) 1.033; 95% CI 0.998-1.069; p = 0.065]. The result was robust against extensive sensitivity analyses.

CONCLUSIONS

Our study indicated a decreased risk of prostate cancer in schizophrenia patients through meta-analysis, while MR analysis did not support the connection between schizophrenia and prostate cancer. Due to the interaction of genetic variants between binary exposures, we need to be cautious in interpreting and presenting causal associations. Moreover, further research is needed to investigate underlying factors that might link schizophrenia to the risk of prostate cancer.

Thyroid Diseases and Breast Cancer

Epidemiological studies aimed at defining the association of thyroid diseases with extra-thyroidal malignancies (EM) have aroused considerable interest in the possibility of revealing common genetic and environmental factors underlying disease etiology and progression. Over the years, multiple lines of evidence indicated a significant relationship between thyroid carcinomas and other primary EM, especially breast cancer. For the latter, a prominent association was also found with benign thyroid diseases. In particular, a meta-analysis revealed an increased risk of breast cancer in patients with autoimmune thyroiditis, and our recent work demonstrated that the odds ratio (OR) for breast cancer was raised in both thyroid autoantibody-positive and -negative patients. However, the OR was significantly lower for thyroid autoantibody-positive patients compared to the negative ones. This is in agreement with findings showing that the development of thyroid autoimmunity in cancer patients receiving immunotherapy is associated with better outcome and supports clinical evidence that breast cancer patients with thyroid autoimmunity have longer disease-free interval and overall survival. These results seem to suggest that factors other than oncologic treatments may play a role in the initiation and progression of a second primary malignancy. The molecular links between thyroid autoimmunity and breast cancer remain, however, unidentified, and different hypotheses have been proposed. Here, we will review the epidemiological, clinical, and experimental data relating thyroid diseases and breast cancer, as well as the possible hormonal and molecular mechanisms underlying such associations.

Pituitary tumors and the risk of other malignancies: is the relationship coincidental or causal?

Pituitary adenomas are benign neoplasms of the pituitary. The most prevalent are prolactinomas and non-functioning pituitary adenomas, followed by growth hormone- and ACTH-secreting adenomas. Most pituitary adenomas seem to be sporadic and their persistent growth is very atypical. No molecular markers predict their behavior. The occurrence of pituitary adenomas and malignancies in the same patient can be either pure coincidence or caused by shared underlying genetic susceptibility involved in tumorigenesis. Detailed family history on cancers/tumors in the first, second and third generation of family members on each side of the family has been reported in a few studies. They found an association of pituitary tumors with positive family history for breast, lung and colorectal cancer. We have reported that in about 50% of patients with pituitary adenomas, an association with positive family history for cancer has been found independent of secretory phenotype (acromegaly, prolactinoma, Cushing's disease or non-functioning pituitary adenomas). We also found earlier onset of pituitary tumors (younger age at diagnosis of pituitary tumors) in patients with a strong family history of cancer. In our recent unpublished series of 1300 patients with pituitary adenomas, 6.8% of patients were diagnosed with malignancy. The latency period between the diagnosis of pituitary adenoma and cancer was variable, and in 33% of patients, it was longer than 5 years. Besides the inherited trophic mechanisms (shared underlying genetic variants), the potential influence of shared complex epigenetic influences (environmental and behavioral factors - obesity, smoking, alcohol intake and insulin resistance) is discussed. Further studies are needed to better understand if patients with pituitary adenomas are at increased risk for cancer.

Integrating machine learning with electronic health record data to facilitate detection of prolactin level and pharmacovigilance signals in olanzapine-treated patients

BACKGROUND AND AIM

Available evidence suggests elevated serum prolactin (PRL) levels in olanzapine (OLZ)-treated patients with schizophrenia. However, machine learning (ML)-based comprehensive evaluations of the influence of pathophysiological and pharmacological factors on PRL levels in OLZ-treated patients are rare. We aimed to forecast the PRL level in OLZ-treated patients and mine pharmacovigilance information on PRL-related adverse events by integrating ML and electronic health record (EHR) data.

METHODS

Data were extracted from an EHR system to construct an ML dataset in 672×384 matrix format after preprocessing, which was subsequently randomly divided into a derivation cohort for model development and a validation cohort for model validation (8:2). The eXtreme gradient boosting (XGBoost) algorithm was used to build the ML models, the importance of the features and predictive behaviors of which were illustrated by SHapley Additive exPlanations (SHAP)-based analyses. The sequential forward feature selection approach was used to generate the optimal feature subset. The co-administered drugs that might have influenced PRL levels during OLZ treatment as identified by SHAP analyses were then compared with evidence from disproportionality analyses by using OpenVigil FDA.

RESULTS

The 15 features that made the greatest contributions, as ranked by the mean (|SHAP value|), were identified as the optimal feature subset. The features were gender_male, co-administration of risperidone, age, co-administration of aripiprazole, concentration of aripiprazole, concentration of OLZ, progesterone, co-administration of sulpiride, creatine kinase, serum sodium, serum phosphorus, testosterone, platelet distribution width, α-L-fucosidase, and lipoprotein (a). The XGBoost model after feature selection delivered good performance on the validation cohort with a mean absolute error of 0.046, mean squared error of 0.0036, root-mean-squared error of 0.060, and mean relative error of 11%. Risperidone and aripiprazole exhibited the strongest associations with hyperprolactinemia and decreased blood PRL according to the disproportionality analyses, and both were identified as co-administered drugs that influenced PRL levels during OLZ treatment by SHAP analyses.

CONCLUSIONS

Multiple pathophysiological and pharmacological confounders influence PRL levels associated with effective treatment and PRL-related side-effects in OLZ-treated patients. Our study highlights the feasibility of integration of ML and EHR data to facilitate the detection of PRL levels and pharmacovigilance signals in OLZ-treated patients.

Pituitary neuroendocrine tumors and differentiated thyroid cancer: do metabolic and inflammatory risk factors play roles?

PURPOSE

It is postulated that patients with different types of pituitary neuroendocrine tumors (PitNETs) may present a higher incidence of cancer. Factors underlying individuals becoming overweight, such as insulin resistance, hyperleptinemia, and low-grade inflammation, may play a role in the risk of differentiated thyroid carcinoma (DTC) in such patients. This study aimed to investigate the frequency of and obesity-related risk factors associated with DTC in patients with PitNETs.

METHODS

This cross-sectional study involved 149 patients with nonacromegalic PitNETs (AG group), 71 patients with acromegaly (ACRO group), and 156 controls (CG group). All participants underwent insulin and blood glucose measurements with the determination of the homeostatic model assessment-insulin resistance (HOMA-IR) index, leptin, and high-sensitivity C-reactive protein (hsCRP), and they also underwent thyroid ultrasound. Clinically significant nodules were biopsied for subsequent cytopathological evaluation, and participants were operated on when indicated.

RESULTS

Patients in the AG group had high levels of insulin resistance and significantly higher levels of leptin and hsCRP compared with those of patients in the ACRO group. There were no cases of DTC in the AG group; two findings, one incidental, of DTC occurred in the CG group, and three cases of DTC were present in the ACRO group. Acromegaly was associated with DTC after adjusted analysis.

CONCLUSIONS

Our findings in patients with nonacromegalic PitNETs do not indicate a high risk for DTC despite the presence of metabolic and inflammatory risk factors for neoplastic events. In contrast, acromegaly promotes a greater risk of DTC.

Prolactinomas and menopause: any changes in management?

PURPOSE

Treatment goals in prolactinomas are to correct hypogonadism, restore fertility and control tumor mass in case of macroadenomas. According to current guidelines, medical treatment of asymptomatic postmenopausal women is not indicated. The purpose of this study was to review the current literature pertaining to biological behavior of prolactinomas during menopause, likelihood of successful dopamine agonist withdrawal during this period and possible prolactin-mediated increased morbidity that could modify current management.

METHODS

A comprehensive literature search including papers published until July 2019 was conducted using PubMed and Medline databases.

RESULTS

Women with prolactinomas entering menopause have a higher chance of prolactin normalization of treatment compared with women in their reproductive years. Although most prolactin secreting adenomas diagnosed during menopause are large, they respond well to dopamine agonist treatment. Data directly linking hyperprolactinemia with an increased risk of cancer and cardiovascular and metabolic morbidity are inconsistent. There is no data indicating that correction of hyperprolactinemia improves clinical outcomes in asymptomatic patients bearing microadenomas.

CONCLUSION

There is no evidence that justifies changing current recommendations to withhold medical treatment of microprolactinomas in asymptomatic post-menopausal women. Macroprolactinoma patients should be treated according to standard clinical practice.

Interrelationship between oxidative stress, DNA damage and cancer risk in diabetes (Type 2) in Riyadh, KSA

Type 2 Diabetes Mellitus (T2DM) is the most widely known type of disorder of the endocrine system marked by hyperglycemia resulting either due to deficiency of insulin and or resistance. Persistent hyperglycemia induces oxidative stress and is suggested to play a prominent role in the pathophysiology underlying T2DM. Besides, oxidative stress can result in DNA damage leading to high cancer risk. Current study aimed to evaluate status of oxidative damage, damage to DNA and cancer biomarkers in regard to increased glucose in T2DM patients and to correlate the glycemic state with cancer. A total of 150 subjects consisting of control (50) and T2DM patients (1 0 0) were enrolled. Additionally, three tertiles were created among the two groups based on levels of HbA1c (Tertile I = 5.37 ± 0.34, n = 50; Tertile II = 6.74 ± 0.20, n = 50; Tertile III = 9.21 ± 1.47, n = 50). Oxidative stress parameters including malondialedehyde (MDA) and antioxidant enzymes were measured. Damage to DNA was analyzed by measuring the levels of DNA damage adduct-8 hydroxy deoxy Guanosine (8-OHdG). To detect cancer resulting from oxidative stress, cancer biomarkers CEA, AFP, CA125, CA-15, CA19-9, prolactin were measured in these subjects. All measurements were analysed by SPSS software. Levels of MDA and antioxidant enzymes altered significantly in T2DM group at p < 0.001 and p < 0.05 level of significance. Significant DNA damage accompanied with elevated levels of CEA, CA19-9 and decreased CA125, AFP and prolactin were noted in T2DM group. CA 19-9 and CEA levels increased at p < 0.05, whereas levels of prolactin decreased significantly (p < 0.001) in T2DM group compared to control. Additionally the mean values of DNA damage adduct 8-OHdG differ significantly at P < 0.01 between the two groups. However, no significant correlation in oxidative stress parameter, antioxidant enzymes, DNA damage and neither with the highest tertile of HbA1c (>7.5%) was noted. Based on the results obtained in the present study, we conclude that there is considerable change in oxidative stress and DNA damage in T2DM patients. Hence, assumption that the oxidative stress could cause cancer in T2DM as a result of hyperglycemic state was not speculated in this study.

Hyperprolactinemia in psychotic patients treated in monotherapy with long-acting injectable antipsychotics

Objectives: Hyperprolactinemia (HPRL), defined as plasma prolactin (PRL) >25 ng/ml, is a frequent adverse effect of the treatment with some antipsychotics. The objectives of this study were to determine the prevalence of HPRL among schizophrenic patients treated with long-acting injectable (LAI) antipsychotic drugs at our hospital, and to estimate gender effects in PRL levels in these patients. Methods: This cross-sectional, retrospective, study analyzed 165 psychotic patients treatment with LAI antipsychotics in monotherapy from February to May of 2017 at the Psychiatry Specialized Care Units of the Elche General Hospital (Spain). Results: The prevalence of antipsychotic-derived HPRL in our hospital was 52.41%. Patients treated with LAI formulations of paliperidone and risperidone presented the highest levels of HPRL. A linear regression model showed that female patients presented 24.95 ng/ml (CI95 = 16.85, 33.05) higher levels of PRL than male patients (p < .0001). For women, age >45 years was associated to reduced levels of PRL with respect to younger patients (mean= -18.86 ng/ml, CI95 = -35.59, -2.13, p < .05). Conclusions: Our study confirmed the effects of LAI paliperidone and risperidone on PRL levels. Sex and age were significantly associated with PRL levels in patients treated with LAI antipsychotics, with younger women presenting higher rates of HPRL than men. Key points HPRL is a common adverse effect of the treatment with antipsychotics, detectable in over half of the patients treated in our hospital. Our study showed that treatment with LAI formulations of paliperidone and risperidone resulted in the highest levels of HPRL. Sex and age were significantly associated with PRL levels in patients treated with LAI antipsychotic drugs, with younger women presenting higher rates of HPRL than men.

STAT5a/b Deficiency Delays, but does not Prevent, Prolactin-Driven Prostate Tumorigenesis in Mice

The canonical prolactin (PRL) Signal Transducer and Activator of Transcription (STAT) 5 pathway has been suggested to contribute to human prostate tumorigenesis via an autocrine/paracrine mechanism. The probasin (Pb)-PRL transgenic mouse models this mechanism by overexpressing PRL specifically in the prostate epithelium leading to strong STAT5 activation in luminal cells. These mice exhibit hypertrophic prostates harboring various pre-neoplastic lesions that aggravate with age and accumulation of castration-resistant stem/progenitor cells. As STAT5 signaling is largely predominant over other classical PRL-triggered pathways in Pb-PRL prostates, we reasoned that Pb-Cre recombinase-driven genetic deletion of a floxed Stat5a/b locus should prevent prostate tumorigenesis in so-called Pb-PRL^ΔSTAT5 mice. Anterior and dorsal prostate lobes displayed the highest Stat5a/b deletion efficiency with no overt compensatory activation of other PRLR signaling cascade at 6 months of age; hence the development of tumor hallmarks was markedly reduced. Stat5a/b deletion also reversed the accumulation of stem/progenitor cells, indicating that STAT5 signaling regulates prostate epithelial cell hierarchy. Interestingly, ERK1/2 and AKT, but not STAT3 and androgen signaling, emerged as escape mechanisms leading to delayed tumor development in aged Pb-PRL^ΔSTAT5 mice. Unexpectedly, we found that Pb-PRL prostates spontaneously exhibited age-dependent decline of STAT5 signaling, also to the benefit of AKT and ERK1/2 signaling. As a consequence, both Pb-PRL and Pb-PRL^ΔSTAT5 mice ultimately displayed similar pathological prostate phenotypes at 18 months of age. This preclinical study provides insight on STAT5-dependent mechanisms of PRL-induced prostate tumorigenesis and alternative pathways bypassing STAT5 signaling down-regulation upon prostate neoplasia progression.

Hyperprolactinemia/Prolactinomas in the Postmenopausal Period: Challenges in Diagnosis and Management

Hyperprolactinemia is not a common finding in postmenopausal women. Prolactinomas detected after menopause are usually macroadenomas. Due to atypical clinical features they may remain unrecognized for a long period of time. Interestingly the growth potential of prolactinomas remains after menopause. Most tumors are invasive and present with high prolactin levels. They respond to medical treatment with dopamine agonists in terms of prolactin normalization, tumor shrinkage, and improvement in pituitary function. Treatment with dopamine agonists is usually long term. Reducing doses of cabergoline to the lowest that keeps prolactin levels normal prior to withdrawal is proposed to patients with macroprolactinomas who normalize prolactin after > 5 years of treatment and who do not have cavernous sinus invasion. Cabergoline can achieve a high percentage of remission maintenance in the first years after withdrawal. However, the percentage of relapse-free patients 5 years after withdrawal is significantly lower. Besides recurrent hyper-prolactinemia in a subgroup of macroprolactinomas after a long-interval tumor regrowth may be detected. Menopause cannot ensure remission of the tumor so long-term surveillance is suggested. In patients with microadenomas data on long-term remission rates (normalization of prolactin and disappearance of the tumor) after suspension of treatment with dopamine agonists are highly variable. The current strategy for microprolactinomas is not to treat hyperprolactinemia in menopause if it recurrs after discontinuation of dopamine agonists. This is based on: (1) reports that elevated prolactin levels may normalize in some women after menopause, (2) the fact that the association between prolactin levels and breast cancer is inconsistent in postmenopausal women, (3) the lack of clinical evidence that normalization of prolactin levels in postmenopausal women improves bone mineral density or reduces the risk of fracture, and (4) the fact that, concerning the metabolic syndrome, no data are available on metabolic parameters after suspension of treatment with dopamine agonists. For a change in strategy, i.e., for the potential benefits from treatment of hyperprolactinemia in the postmenopausal period with dopamine agonists concerning weight loss, improved insulin sensitivity, decreased fracture risk, and improved sexuality, more evidence is needed.

Giant prolactinoma, germline BRCA1 mutation, and depression: a case report

Background

Giant prolactinomas are very rare pituitary tumors that may exhibit an aggressive behavior and present with a life-threatening condition.

Case presentation

A 25-year-old white woman was admitted to our hospital with a headache, psychomotor retardation, reduced vision, and loss of autonomy in daily activities. Her past medical history was significant for having oligomenorrhea and a depressive syndrome since her mother’s death. She also had a breast cancer gene 1 (BRCA1) mutation and a family history of breast cancer. She had marked hyperprolactinemia (7615 ng/dL), central hypocortisolism, growth hormone deficiency, and a giant pituitary tumor (52 × 30 × 33 mm) which was shown in magnetic resonance imaging with obstructive hydrocephalus, requiring emergency surgery. Treatment with cabergoline led to a 99.8% reduction in serum prolactin levels and significant tumor shrinkage. Her depressive symptoms progressively improved and psychiatric drugs were withdrawn after 3 months of cabergoline treatment. Currently, she is being followed in Endocrinology, Neurosurgery, and Neurophthalmology out-patient clinics and in a breast cancer unit. Careful monitoring, support, and follow-up will be essential throughout this patient’s life.

Conclusions

This case is a rare presentation of a giant prolactinoma in a young woman, who presented a life-threatening event. She also had an unexpected association between diseases or symptoms that may have contributed to the delay in diagnosis. Given the concomitant presence of a giant prolactinoma, a BRCA1 mutation, and depressive symptoms, a possible association was hypothesized. The breast cancer risk in a BRCA1 mutation carrier and the possible interference of hyperprolactinemia and life events were also discussed. However this hypothesis requires further investigation.

Macroprolactinoma causing VI, X, XII cranial nerve palsies nearly 30 years after initial treatment

A 48-year-old man was diagnosed with a large macroprolactinoma in 1982 treated with surgery, adjuvant radiotherapy and bromocriptine. Normal prolactin was achieved in 2005 but in 2009 it started rising. Pituitary MRIs in 2009, 2012, 2014 and 2015 were reported as showing empty pituitary fossa. Prolactin continued to increase (despite increasing bromocriptine dose). Trialling cabergoline had no effect (prolactin 191,380 mU/L). In January 2016, he presented with right facial weakness and CT head was reported as showing no acute intracranial abnormality. In late 2016, he was referred to ENT with hoarse voice; left hypoglossal and recurrent laryngeal nerve palsies were found. At this point, prolactin was 534,176 mU/L. Just before further endocrine review, he had a fall and CT head showed a basal skull mass invading the left petrous temporal bone. Pituitary MRI revealed a large enhancing mass within the sella infiltrating the clivus, extending into the left petrous apex and occipital condyle with involvement of the left Meckel's cave, internal acoustic meatus, jugular foramen and hypoglossal canal. At that time, left abducens nerve palsy was also present. CT thorax/abdomen/pelvis excluded malignancy. Review of previous images suggested that this lesion had started becoming evident below the fossa in pituitary MRI of 2015. Temozolomide was initiated. After eight cycles, there is significant tumour reduction with prolactin 1565 mU/L and cranial nerve deficits have remained stable. Prolactinomas can manifest aggressive behaviour even decades after initial treatment highlighting the unpredictable clinical course they can demonstrate and the need for careful imaging review.

Learning points

Aggressive behaviour of prolactinomas can manifest even decades after first treatment highlighting the unpredictable clinical course these tumours can demonstrate.Escape from control of hyperprolactinaemia in the absence of sellar adenomatous tissue requires careful and systematic search for the anatomical localisation of the lesion responsible for the prolactin excess.Temozolomide is a valuable agent in the therapeutic armamentarium for aggressive/invasive prolactinomas, particularly if they are not amenable to other treatment modalities.

Domperidone use and risk of primary liver cancer in the Clinical Practice Research Datalink

BACKGROUND

Pronounced sex-disparity in liver cancer suggests a role for hormones, one of which could be prolactin. Stimulation of prolactin production in mice via domperidone has been reported to decrease hepatocarcinogenesis, thus may have chemopreventive potential. To study the effect of domperidone in humans, a large medical records study was conducted.

METHODS

Based in the Clinical Practice Research Datalink, 1921 liver cancer cases and 7681 controls were identified. Conditional logistic regression was employed to estimate odds ratios (OR) and 95% confidence intervals (CI). Domperidone use was analyzed overall, and by number of prescriptions and cumulative dose.

RESULTS

Comparing ever- versus never-use, there was no association between domperidone and liver cancer among men (OR = 1.06, 95% CI: 0.76-1.48) or women (OR = 1.21, 95% CI: 0.82-1.76). Among men, there was no association with dose or number of prescriptions, while among women who received the highest doses (OR_{2700 mg vs. 0 mg} = 2.52, 95% CI: 1.18-5.41, p-trend = 0.02) and greatest number of prescriptions (OR_{≥11 Rx vs. 0 Rx} = 3.17, 95% CI: 1.07-9.40, p-trend = 0.02) there was a significantly increased risk, although there was no evidence of heterogeneity in the results by gender.

CONCLUSION

Domperidone use was not associated with decreased liver cancer risk among all study participants. Among women, an increased risk at highest levels of exposure warrants further study.

Prolactinoma through the female life cycle

Prolactinomas are the most common secretory pituitary adenoma. They typically occur in women in the 3rd-6th decade of life and rarely in the pediatric population or after menopause. Most women present with irregular menses and/or infertility. Dopamine (DA) agonists, used in their treatment, are safe during pregnancy, but in most cases are discontinued at conception with close monitoring for signs or symptoms of tumor growth. Breastfeeding is safe postpartum, provided there was no significant growth during pregnancy. Some women will experience normalization of prolactin levels postpartum. Menopause may also decrease prolactin levels and even those with macroprolactinomas may consider discontinuing their DA agonist with close follow-up. Prolactinomas may be associated with decreased quality of life scores in women, and play a role in bone health and cardiovascular risk factors. This review discusses the current literature and clinical understanding of prolactinomas throughout the entirety of the female life cycle.

Cancer prevalence in Israeli men and women with schizophrenia

The aim of this cross-sectional study was to compare cancer prevalence rates among patients with schizophrenia to those of the non-schizophrenia population. The study population included members of Clalit Health Services aged 25 to 74 years and all data was taken from patients' electronic health records. Of the 2,060,314 members who were included in the study, 32,748 had a diagnosis of schizophrenia. Cancer prevalence rates in women with and without schizophrenia were 491 per 10,000 and 439 per 10,000, respectively; in men, cancer prevalence rates were 226 per 10,000 and 296 per 10,000, respectively. The age-adjusted prevalence rate of all-type cancer was significantly lower among men with schizophrenia, compared to men without schizophrenia; specifically, men with schizophrenia had a lower rate of prostate cancer, and of cancers in the "other" category, compared to men without schizophrenia. Reduced cancer rates in men with schizophrenia may reflect under-diagnosis of some cancer types, likely due to insufficient medical attention. An effort to improve screening regimes should be made.

Morbidity and mortality in patients with hyperprolactinaemia: the PROLEARS study

PURPOSE

High serum prolactin concentrations have been associated with adverse health outcomes in some but not all studies. This study aimed to examine the morbidity and all-cause mortality associated with hyperprolactinaemia.

METHODS

A population-based matched cohort study in Tayside (Scotland, UK) from 1988 to 2014 was performed. Record-linkage technology was used to identify patients with hyperprolactinaemia that were compared to an age-sex-matched cohort of patients free of hyperprolactinaemia. The number of deaths and incident admissions with diabetes mellitus, cardiovascular disease, cancer, breast cancer, bone fractures and infectious conditions were compared by the survival analysis.

RESULTS

Patients with hyperprolactinaemia related to pituitary tumours had no increased risk of diabetes, cardiovascular disease, bone fractures, all-cause cancer or breast cancer. Whilst no increased mortality was observed in patients with pituitary microadenomas (HR = 1.65, 95% CI: 0.79-3.44), other subgroups including those with pituitary macroadenomas and drug-induced and idiopathic hyperprolactinaemia demonstrated an increased risk of death. Individuals with drug-induced hyperprolactinaemia also demonstrated increased risks of diabetes, cardiovascular disease, infectious disease and bone fracture. However, these increased risks were not associated with the degree of serum prolactin elevation (P_trend > 0.3). No increased risk of cancer was observed in any subgroup.

CONCLUSIONS

No excess morbidity was observed in patients with raised prolactin due to pituitary tumours. Although the increased morbidity and mortality associated with defined patient subgroups are unlikely to be directly related to the elevation in serum prolactin, hyperprolactinaemia might act as a biomarker for the presence of some increased disease risk in these patients.

Prolactinoma in a Dog

A 12-year-old male Yorkshire Terrier was presented because of decreased appetite. Physical examination revealed mammary gland swelling and galactorrhea. Contrast-enhanced computed tomographic scanning of the skull indicated an enlarged pituitary gland, compatible with a pituitary tumor. The serum prolactin concentration was markedly elevated. One week after the start of treatment with the dopamine agonist cabergoline, the serum prolactin concentration normalized and the galactorrhea resolved. Cabergoline was administered for approximately 4 months and then discontinued. Subsequently, serum prolactin concentration increased again, and mammary gland swelling and galactorrhea reappeared. The dog was euthanized 10 months after the first detection of the galactorrhea because of problems not directly related to pituitary disease. Postmortem examination revealed an infiltrative adenoma of the pituitary gland with immunolabeling for prolactin. The clinical and histopathologic findings indicated the diagnosis of a functional prolactinoma in a male dog.

Risk of breast cancer in risperidone users: A nationwide cohort study

BACKGROUND

Several antipsychotics, especially risperidone, are known to increase serum prolactin. Hyperprolactinemia has been linked to the development of mammary gland tumors in animal studies. We therefore investigated the risk of breast cancer in a nationwide cohort of women using risperidone or other antipsychotics.

METHODS

All women, 18years or older, who initiated treatment with risperidone or any other antipsychotic between 2006 and 2012 were identified in Swedish nationwide registers. Patients with two consecutive dispensations of the same antipsychotic within 3months, no previous cancer diagnosis, and no previous dispensations of paliperidone were included. The final cohort consisted of 55976 women of whom 22908, 24524, and 8544 were exposed to risperidone, other atypical antipsychotics, and typical antipsychotics, respectively. A Cox regression model was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between antipsychotics and breast cancer.

RESULTS

Patients were followed prospectively, the mean follow-up time ranging from 2.4 to 2.8years between treatment groups. After adjusting for age, there was no increased risk for breast cancer among risperidone users compared to patients exposed to another atypical antipsychotic (HR 0.94, 95% CI 0.72-1.22) or a typical antipsychotic (HR 1.25, 95% CI 0.94-1.66). Analyses stratified by tumor stage, using active treatment follow-up time, or including only treatment naïve patients did not reveal any noteworthy change in the results.

CONCLUSION

Risperidone use does not confer an increased short-term risk of breast cancer compared to other antipsychotic agents.

Breast carcinoma associated with prolactinoma: A case report

We report a 28-year-old woman who presented with a 6-year history of milk-like discharge from both of her nipples and was diagnosed with prolactinoma based on computed tomography (CT) findings and serum prolactin level. Further breast examination revealed a mass located in the upper outer region of the left breast. She underwent subtotal pituitary tumor resection. Thereafter, modified radical mastectomy was performed for left breast cancer. Twelve years after treatment, prolactinoma recurrence was detected, and bromocriptine therapy was administered. No recurrence of breast cancer was discovered. Based on this case report, we stress the importance of prolactin levels due to their possible biologic effects on breast cancer induction or growth.

Monitoring of prolactin levels in children and adolescents prescribed antipsychotic medication: a complete audit cycle

Aims and methods Antipsychotics have proven benefits in children and adolescents with autism spectrum disorders. However, notwithstanding some therapeutic benefits significant side effects are associated with the use of antipsychotics, such as hyperprolactinaemia. We completed an audit cycle between April 2013 and December 2013 to evaluate the practice in the Beechpark Autism Service with respect to monitoring and managing hyperprolactinaemia in children and adolescents prescribed antipsychotics. The re-audit assessed whether the recommended guidelines and changes had been implemented. The National Institute for Health and Care Excellence guidelines were used as a gold standard for this audit.

RESULTS

Basal determinations of serum prolactin improved significantly at the end of the audit cycle (28.6% v. 57%) with slight improvement in six monthly repeat prolactin monitoring (28.6% v. 39.1%) showing some change in clinical practice. However, there was minimal improvement in managing hyperprolactinaemia (0% v. 12.5%). Clinical implication There is growing awareness about hyperprolactinaemia associated with the use of antipsychotic medication in children and adolescents and the long-term effects. Clear documented guidelines will help increase and improve the monitoring and management of hyperprolactinaemia in these groups of patients. However, more needs to be done in improving the practice of monitoring and managing hyperprolactinaemia in children and adolescent prescribed antipsychotic medication giving the documented long-term effects.

Differentiated thyroid cancer in patients with prolactinoma

BACKGROUND/AIM

Increasing evidence is available about the role of prolactin in the development of various cancers. The purpose of this study is to evaluate the frequency of thyroid cancer in patients with prolactinoma followed at a single site.

MATERIALS AND METHODS

The medical records of 182 patients diagnosed with prolactinoma were reviewed retrospectively. Serum prolactin, antithyroglobulin, antithyroid peroxidase antibody, thyroid-stimulating hormone, free T4, and free T3 values and pituitary gland magnetic resonance imaging and thyroid ultrasound reports were evaluated.

RESULTS

Forty-five (39.5%) patients were found to have a thyroid nodule (13 solitary, 32 multiple). Ten patients were administered a thyroidectomy, and differentiated thyroid cancer (DTC) was detected in 6 of these patients (6/114, 5.3%). One patient had lung metastasis. The control group consisted of 113 individuals (101 females, 12 males with a mean age of 32.1 ± 9.1). In the ultrasound reports, 28 of these individuals (24.8%) had a thyroid nodule (5 solitary, 23 multiple), and one individual (1/113, 0.8%) had DTC.

CONCLUSION

When compared to the control group, thyroid volume and thyroid nodularity were significantly higher in patients with prolactinoma (P < 0.001, P = 0.018, respectively); however, no statistically significant difference existed for the incidence of thyroid cancer (P = 0.196).

Spanish consensus on the risks and detection of antipsychotic drug-related hyperprolactinaemia

INTRODUCTION

Iatrogenic hyperprolactinaemia (IHPRL) has been more frequently related to some antipsychotic drugs that provoke an intense blockade of dopamine D2 receptors. There is a wide variation in clinical practice, and perhaps some more awareness between clinicians is needed. Due to the high frequency of chronic treatment in severe mental patients, careful attention is recommended on the physical risk. IHPRL symptoms could be underestimated without routine examination.

METHODOLOGY

An intense scientific literature search was performed in order to draw up a multidisciplinary consensus, including different specialists of psychiatry, endocrinology, oncology and internal medicine, and looking for a consensus about clinical risk and detection of IHPRL following evidence-based medicine criteria levels (EBM I- IV).

RESULTS

Short-term symptoms include amenorrhea, galactorrhoea, and sexual dysfunction with decrease of libido and erectile difficulties related to hypogonadism. Medium and long-term symptoms related to oestrogens are observed, including a decrease bone mass density, hypogonadism, early menopause, some types of cancer risk increase (breast and endometrial), cardiovascular risk increase, immune system disorders, lipids, and cognitive dysfunction. Prolactin level, gonadal hormones and vitamin D should be checked in all patients receiving antipsychotics at baseline although early symptoms (amenorrhea-galactorrhoea) may not be observed due to the risk of underestimating other delayed symptoms that may appear in the medium term. Routine examination of sexual dysfunction is recommended due to possible poor patient tolerance and low compliance. Special care is required in children and adolescents, as well as patients with PRL levels >50ng/ml (moderate hyperprolactinaemia). A possible prolactinoma should be investigated in patients with PRL levels >150ng/ml, with special attention to patients with breast/endometrial cancer history. Densitometry should be prescribed for males >50 years old, amenorrhea>6 months, or early menopause to avoid fracture risk.

Relationship between prolactin, breast cancer risk, and antipsychotics in patients with schizophrenia: a critical review

OBJECTIVE

A recent meta-analysis showed that breast cancer probably is more common in female patients with schizophrenia than in the general population (effect size = 1.25, P < 0.05). Increasing experimental and epidemiological data have alerted researchers to the influence of prolactin (PRL) in mammary carcinogenesis. We therefore investigated the possible relationship between antipsychotic-induced hyperprolactinemia (HPRL) and breast cancer risk in female patients with schizophrenia.

METHOD

A literature search (1950 until January 2015), using the MEDLINE database, was conducted for English-language published clinical trials to identify and synthesize data of the current state of knowledge concerning breast cancer risk (factors) in women with schizophrenia and its (their) relationship between HPRL and antipsychotic medication.

RESULTS

Although an increasing body of evidence supports the involvement of PRL in breast carcinogenesis, results of human prospective studies are limited, equivocal, and correlative (with risk ratios ranging from 0.70 to 1.9 for premenopausal women and from 0.76 to 2.03 for postmenopausal women). Moreover, these studies equally do not take into account the local production of PRL in breast epithelium, although amplification or overexpression of the local autocrine/paracrine PRL loop may be a more important mechanism in tumorigenesis. Until now, there is also no conclusive evidence that antipsychotic medication can increase the risk of breast malignancy and mortality.

CONCLUSION

Other breast risk factors than PRL, such as nulliparity, obesity, diabetes mellitus, and unhealthy lifestyle behaviours (alcohol dependence, smoking, low physical activity), probably are of greater relevance in individual breast cancer cases within the population of female patients with schizophrenia.

Increased micronucleus, nucleoplasmic bridge, nuclear bud frequency and oxidative DNA damage associated with prolactin levels and pituitary adenoma diameters in patients with prolactinoma

Prolactinoma is the most common pituitary tumor. Most pituitary tumors are benign, but they often are clinically significant. We investigated cytokinesis-block micronucleus cytome (CBMN cyt) assay parameters and oxidative DNA damage in patients with prolactinoma to assess the relations among age, prolactin level, pituitary adenoma diameter and 8-hydroxy-2'-deoxyguanosine (8-OHdG) level in patients with prolactinoma. We investigated 27 patients diagnosed with prolactinoma and 20 age- and sex-matched healthy controls. We measured CBMN cyt parameters and plasma 8-OHdG levels in peripheral blood lymphocytes of patients with prolactinoma and controls. The frequencies of micronucleus (MN), nucleoplasmic bridge, nuclear bud, apoptotic and necrotic cells, and plasma 8-OHdG levels in patients with prolactinoma were significantly greater than controls. MN frequency was correlated positively with age, prolactin levels and pituitary adenoma diameters in patients with prolactinoma. The increased chromosomal and oxidative DNA damage, and the positive correlation between MN frequency, prolactin levels and pituitary adenoma diameters may be associated with increased risk of cancer in patients with prolactinoma, because increased MN frequency is a predictor of cancer risk.

STAT3 activation is required for the antiapoptotic effects of prolactin in cervical cancer cells

BACKGROUND

Prolactin (PRL) has been implicated in the development of different types of cancer. However, signaling pathways might be activated depending on various forms of prolactin receptor (PRLR). JAK/STAT is an important pathway associated with PRL effects. The activation of JAK/STAT pathway might activate antiapoptotic genes that could importantly lead to progression of tumorigenesis. Recently, we have reported that PRL is associated with cell survival by inhibition of apoptosis and the precise activated signaling pathways for this process are still questioned. The purpose of this study was to evaluate the activation of different signaling pathways in response to PRL as well as to identify the induction of antiapoptotic genes.

METHODS

Cervical cancer cell lines HeLa, SiHa and C-33 A were stimulated with PRL (200 ng/mL) for 30 and 60 min and non stimulated cells were used to measure basal protein expression. Inhibition assays were performed by using Jak2 specific inhibitor AG490, either alone or in combination with PRL for 48 h. Western blot were carried out to evaluate protein induction of the different signaling pathways and antiapoptotic proteins. Significant effects were determined by using ANOVA test.

RESULTS

STAT3 was significantly activated in cervical cancer lines in comparison with non-tumorigenic keratinocytes HaCaT. No significant differences were found when analyzing MAPK and PI3K signaling pathways. An increase of antiapoptotic genes Bcl-xl, Bcl-2, survivin and Mcl-1 was observed after stimulus with PRL; however, after inhibition with AG490, the induction of antiapoptotic genes was decreased.

CONCLUSION

Our data suggests that STAT3 is an important signaling pathway activated by PRL in cervical cancer cells and it modulates the induction of antiapoptotic genes. Blocking STAT3 could represent a possible therapeutic strategy in cervical cancer.

Breast cancer risk in hyperprolactinemia: a population-based cohort study and meta-analysis of the literature

OBJECTIVE

To enhance the precision of the risk estimate for breast cancer in hyperprolactinemia patients by collecting more data and pooling our results with available data from former studies in a meta-analysis.

DESIGN

Population-based cohort study and meta-analysis of the literature.

METHODS

Using nationwide registries, we identified all patients with a first-time diagnosis of hyperprolactinemia during 1994-2012 including those with a new breast cancer diagnoses after the start of follow-up. We calculated standardised incidence ratios (SIRs) as a measure of relative risk (RR) using national cancer incidence rates. We performed a meta-analysis, combining data from our study with data in the existing literature.

RESULTS

We identified 2457 patients with hyperprolactinemia and 20 breast cancer cases during 19,411 person-years of follow-up, yielding a SIR of 0.99 (95% CI 0.60-1.52). Data from two additional cohort studies were retrieved and analyzed. When the three risk estimates were pooled, the combined RR was 1.04 (95% CI 0.75-1.43).

CONCLUSIONS

We found no increased risk of breast cancer among patients with hyperprolactinemia.

The prolactin receptor as a therapeutic target in human diseases: browsing new potential indications

INTRODUCTION

Prolactin (PRL) signaling has emerged as a relevant target in breast and prostate cancers. This has encouraged various laboratories to develop compounds targeting the PRL receptor (PRLR). As the latter is widely distributed, it is timely to address whether other conditions could also benefit from such inhibitors.

AREAS COVERED

The authors briefly overview the two classes of PRLR blockers, which involve: i) PRL-core based analogs that have been validated as competitive antagonists in various preclinical models, and ii) anti-PRLR neutralizing antibodies that are currently in clinical Phase I for advanced breast and prostate cancers. The main purpose of this review is to discuss the multiple organs/diseases that may be considered as potential targets/indications for such inhibitors. This is done in light of reports suggesting that PRLR expression/signaling is increased in disease, and/or that systemic or locally elevated PRL levels correlate with (or promote) organ pathogenesis.

EXPERT OPINION

The two immediate challenges in the field are i) to provide the scientific community with potent anti-prolactin receptor antibodies to map prolactin receptor expression in target organs, and ii) to take advantage of the availability of functionally validated PRLR blockers to establish the relevance of these potential indications in humans.

New insights in prolactin: pathological implications

Prolactin is a hormone that is mainly secreted by lactotroph cells of the anterior pituitary gland, and is involved in many biological processes including lactation and reproduction. Animal models have provided insights into the biology of prolactin proteins and offer compelling evidence that the different prolactin isoforms each have independent biological functions. The major isoform, 23 kDa prolactin, acts via its membrane receptor, the prolactin receptor (PRL-R), which is a member of the haematopoietic cytokine superfamily and for which the mechanism of activation has been deciphered. The 16 kDa prolactin isoform is a cleavage product derived from native prolactin, which has received particular attention as a result of its newly described inhibitory effects on angiogenesis and tumorigenesis. The discovery of multiple extrapituitary sites of prolactin secretion also increases the range of known functions of this hormone. This Review summarizes current knowledge of the biology of prolactin and its receptor, as well as its physiological and pathological roles. We focus on the role of prolactin in human pathophysiology, particularly the discovery of the mechanism underlying infertility associated with hyperprolactinaemia and the identification of the first mutation in human PRLR.

[Prolactinoma]

Prolactinomas are the most common pituitary adenomas that affect young women at fertile age. Hyperprolactinemia causes hypogonadism, menstrual irregularities or amenorrhea in women, low serum testosterone levels in men, and infertility and sexual dysfunction in both men and women. Macroprolactinomas may cause cephalea, visual disturbance, and hypopituitarism. Clinical treatment with dopamine agonists is the gold standard, with cabergoline as the first choice due to its greater efficiency and tolerability. In about 20% of the cases, treatment is partially or completely ineffective, a situation in which surgery, in general by transsphenoidal route, is indicated. Radiotherapy is indicated only in the control of tumor growth in invasive/aggressive cases. In invasive macroprolactinoma, the necessary approach, in general, is the combination of several therapeutic modalities, including debulking and recently-approved drugs, such as temozolamide. As for pregnancy, the drug of choice to induce ovulation still is bromocriptine. In the cases of microprolactinomas and intrasselar macroprolactinomas, the treatment with dopaminergic agonists may be suspended after pregnancy is confirmed. In macroprolactinomas, management should be individualized.

Minireview: prolactin regulation of adult stem cells

Adult stem/progenitor cells are found in many tissues, where their primary role is to maintain homeostasis. Recent studies have evaluated the regulation of adult stem/progenitor cells by prolactin in various target tissues or cell types, including the mammary gland, the prostate, the brain, the bone marrow, the hair follicle, and colon cancer cells. Depending on the tissue, prolactin can either maintain stem cell quiescence or, in contrast, promote stem/progenitor cell expansion and push their progeny towards differentiation. In many instances, whether these effects are direct or involve paracrine regulators remains debated. This minireview aims to overview the current knowledge in the field.

Risk of prostate cancer in patients with schizophrenia

OBJECTIVES

To examine the rate of prostate cancer in a cohort of schizophrenia in-patients in the PSA-era as compared to expected rates. There is conflicting evidence on the relative risk of prostate cancer in men with schizophrenia.

METHODS

the study sample was comprised of schizophrenia patients who had been admitted to a tertiary care mental health center between 1990 and 2011. The data for the sample was cross-referenced with the National Cancer Registry. Analyses of Standardized Incidence Rates (SIR) for prostate cancer and for lung cancer (representing an organ system not sensitive to sex hormones) were performed.

RESULTS

Of 4,326 schizophrenia patients included in the present study, 181 (4.2%) were diagnosed with cancer at any site. Only 10 of these patients were diagnosed with prostate cancer. This reflects a reduced risk; SIR of 0.56 (95% CI 0.27-1.03). In the same cohort, 33 schizophrenia patients were diagnosed with lung cancer presenting a SIR of 1.43 (95% CI 0.98-2.01) in this sample.

CONCLUSIONS

The present study suggests a reduced rate of prostate cancer in patients admitted for schizophrenia. There are several possible explanations for this finding including chronic state of hyperprolactinemia induced by antipsychotic drugs.

Urinary nickel and prolactin in workers exposed to urban stressors

The aim of our study is to verify whether the exposure to low Ni doses in urban air may have some effects on the prolactin values of outdoor workers exposed to urban pollutants. 334 workers have been included in the study and divided on the basis of gender, job, age, length of service and smoking habits. Each worker underwent urinary Ni and prolactin sampling. The t-test for independent samples, the Mann-Whitney U test for two mode variables (gender, smoking habit), the univariate ANOVA test and the Kruskal Wallis test for the variables in more than two modes (age, length of service and job duties) were performed on the total sample. Pearson's correlation coefficient (p two-tailed) among the parameters was evaluated both in the total sample and after the stratification by gender, smoking habit and job. Multiple linear regression was performed after taking account of the major confounding factors on the total sample and on the subcategories. The statistical tests showed a significant correlation between urinary Ni and prolactin both in the total sample and in the subcategories. We believe that the occupational exposure to low doses of Ni present in urban pollution may influence the prolactin values in exposed workers.

Circulatory estrogen level protects against breast cancer in obese women

Literary data suggest apparently ambiguous interaction between menopausal status and obesity-associated breast cancer risk based on the principle of the carcinogenic capacity of estrogen. Before menopause, breast cancer incidence is relatively low and adiposity is erroneously regarded as a protective factor against this tumor conferred by the obesity associated defective estrogen-synthesis. By contrast, in postmenopausal cases, obesity presents a strong risk factor for breast cancer being mistakenly attributed to the presumed excessive estrogen-production of their adipose-tissue mass. Obesity is associated with dysmetabolism and endangers the healthy equilibrium of sexual hormone-production and regular menstrual cycles in women, which are the prerequisites not only for reproductive capacity but also for somatic health. At the same time, literary data support that anovulatory infertility is a very strong risk for breast cancer in young women either with or without obesity. In the majority of premenopausal women, obesity associated insulin resistance is moderate and may be counteracted by their preserved circulatory estrogen level. Consequently, it is not obesity but rather the still sufficient estrogen-level, which may be protective against breast cancer in young adult females. In obese older women, never using hormone replacement therapy (HRT) the breast cancer risk is high, which is associated with their continuous estrogen loss and increasing insulin-resistance. By contrast, obese postmenopausal women using HRT, have a decreased risk for breast cancer as the protective effect of estrogen-substitution may counteract to their obesity associated systemic alterations. The revealed inverse correlation between circulatory estrogen-level and breast cancer risk in obese women should advance our understanding of breast cancer etiology and promotes primary prevention measures. New patents recommend various methods for the prevention and treatment of obesity-related systemic disorders and the associated breast cancer.

SOCS2 mediates the cross talk between androgen and growth hormone signaling in prostate cancer

Anabolic signals such as androgens and the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis play an essential role in the normal development of the prostate but also in its malignant transformation. In this study, we investigated the role of suppressor of cytokine signaling 2 (SOCS2) as mediator of the cross talk between androgens and GH signals in the prostate and its potential role as tumor suppressor in prostate cancer (PCa). We observed that SOCS2 protein levels assayed by immunohistochemistry are elevated in hormone therapy-naive localized prostatic adenocarcinoma in comparison with benign tissue. In contrast, however, castration-resistant bone metastases exhibit reduced levels of SOCS2 in comparison with localized or hormone naive, untreated metastatic tumors. In PCa cells, SOCS2 expression is induced by androgens through a mechanism that requires signal transducer and activator of transcription 5 protein (STAT5) and androgen receptor-dependent transcription. Consequentially, SOCS2 inhibits GH activation of Janus kinase 2, Src and STAT5 as well as both cell invasion and cell proliferation in vitro. In vivo, SOCS2 limits proliferation and production of IGF-1 in the prostate in response to GH. Our results suggest that the use of GH-signaling inhibitors could be of value as a complementary treatment for castration-resistant PCa.

SUMMARY

Androgen induced SOCS2 ubiquitin ligase expression and inhibited GH signaling as well as cell proliferation and invasion in PCa, whereas reduced SOCS2 was present in castration-resistant cases. GH-signaling inhibitors might be a complementary therapeutic option for advanced PCa.

Association of craniopharyngioma and pituitary adenoma

Intracranial tumors of different histologic types infrequently affect patients with pituitary adenomas and no history of head irradiation. The association with craniopharyngioma is extremely rare. Aims of this paper are: (1) to provide a critical literature review of typical features of pituitary adenoma presenting in association with craniopharyngioma; (2) to describe the first documented (clinically, biochemically, histologically, and radiologically) case of aggressive, suprasellar papillary craniopharyngioma presenting with amenorrhea, progressive reduction of visual field, and severe headache in a 38-year-old woman, a decade after surgical cure for microprolactinoma associated with empty sella, during which she had carried two pregnancies; and (3) to discuss common etiopathogenetic mechanisms, in relation to the management of these lesions. Systematic literature search for English literature focusing on the association of craniopharyngioma and pituitary adenoma was performed using PubMed database. Additional relevant articles from references lists were also included. Clinical, laboratory, and radiological examinations performed in our patient for the two brain lesions at diagnosis and follow up were collected. Literature search retrieved nine articles. Typically, craniopharyngioma were of adamantinomatous type, occurred simultaneously to pituitary adenoma, presented with headache and visual loss, and affected men. No case of clearly documented metachronous lesion affecting a woman after pregnancy had been described before. Although very rare and with uncertain etiopathogenesis, second tumors (i.e., craniopharyngioma) should be considered in patients with a history of pituitary adenoma, presenting with suggestive signs and symptoms, even after a long disease-free period, in order to provide proper and prompt treatment.

A 20-year prospective study of plasma prolactin as a risk marker of breast cancer development

Understanding how the timing of exposure to endogenous hormones influences cancer development is critical to elucidating disease etiology. Prolactin increases proliferation and cell motility, processes important in later stage tumor development, suggesting that levels proximate (versus distant) to diagnosis may better predict risk. Thus, we calculated relative risks (RR) and 95% confidence intervals (CI) for prolactin levels on samples collected <10 (proximate) versus ≥10 (distant) years before diagnosis in the Nurses' Health Study (NHS) and NHSII with breast cancer risk, including in a subset of NHS women providing two samples 10 years apart. We measured prolactin via immunoassay in cases diagnosed from 1990 to 2010 (NHS) and 1999 to 2009 (NHSII) and matched controls. Overall, 2,468 cases and 4,021 controls had prolactin measured <10 years and 953 cases and 1,339 controls >10 years before diagnosis/reference date. There was an increased risk for higher proximate prolactin levels [RR, >15.7 vs. ≤8.1 ng/mL (i.e., top vs. bottom quartiles) = 1.20; 95% CI, 1.03-1.40; Ptrend = 0.005], but not for distant levels (RR = 0.97; Ptrend = 0.94); results were similar among women with two blood samples (Pinteraction, proximate vs. distant = 0.07). The positive association was stronger for ER(+) disease (RR = 1.28; Ptrend = 0.003) and postmenopausal women (RR = 1.37; Ptrend = 0.0002). Among postmenopausal women, the association was strongest for ER(+) disease (RR = 1.52) and lymph node-positive cases (RR = 1.63). Our data suggest that prolactin levels measured <10 years before diagnosis are most strongly associated with postmenopausal breast cancer risk, especially for ER(+) tumors and metastatic disease. This corresponds with biologic data that prolactin is etiologically important in tumor promotion.

Changes in pituitary function with ageing and implications for patient care

The pituitary gland has a role in puberty, reproduction, stress-adaptive responses, sodium and water balance, uterine contractions, lactation, thyroid function, growth, body composition and skin pigmentation. Ageing is marked by initially subtle erosion of physiological signalling mechanisms, resulting in lower incremental secretory-burst amplitude, more disorderly patterns of pituitary hormone release and blunted 24 h rhythmic secretion. Almost all pituitary hormones are altered by ageing in humans, often in a manner dependent on sex, body composition, stress, comorbidity, intercurrent illness, medication use, physical frailty, caloric intake, immune status, level of exercise, and neurocognitive decline. The aim of this article is to critically discuss the mechanisms mediating clinical facets of changes in the hypothalamic-pituitary axis during ageing, and the extent to which confounding factors operate to obscure ageing-related effects.

Prolactin and cancer: Has the orphan finally found a home?

Prolactin has, for long, been associated with galactorrhea and infertility in women while its role in men is largely unknown. Recently, expression of prolactin in various other tissues like the breast, prostate, decidua, and the brain has been recognized. This has led to evaluation of paracrine and autocrine actions of prolactin at these tissues and a possible role in development of various cancers. Increased expression of PRL receptors has also been implicated in carcinogenesis. Breast cancer has the strongest association with increased prolactin and prolactin receptor levels. Prostate cancer also has reported significant association, while the role of prolactin in colorectal, gynecological, laryngeal, and hepatocellular cancers is more tenuous. Prolactin/prolactin receptor pathway has also been implicated in development of resistance to chemotherapy. Thus, the effects of this pathway in carcinogenesis seem widespread. At the same time, they also offer an exciting new approach to hormonal manipulation of cancers, especially the treatment-resistant cancers.