Association of prolactin receptor (PRLR) variants with prolactinomas

Prolactinomas are the most frequent type of pituitary tumors, which represent 10–20% of all intracranial neoplasms in humans. Prolactinomas develop in mice lacking the prolactin receptor (PRLR), which is a member of the cytokine receptor superfamily that signals via Janus kinase-2-signal transducer and activator of transcription-5 (JAK2-STAT5) or phosphoinositide 3-kinase-Akt (PI3K-Akt) pathways to mediate changes in transcription, differentiation and proliferation. To elucidate the role of the PRLR gene in human prolactinomas, we determined the PRLR sequence in 50 DNA samples (35 leucocytes, 15 tumors) from 46 prolactinoma patients (59% males, 41% females). This identified six germline PRLR variants, which comprised four rare variants (Gly57Ser, Glu376Gln, Arg453Trp and Asn492Ile) and two low-frequency variants (Ile76Val, Ile146Leu), but no somatic variants. The rare variants, Glu376Gln and Asn492Ile, which were in complete linkage disequilibrium, and are located in the PRLR intracellular domain, occurred with significantly higher frequencies (P 1.3-fold, P < 0.02) and proliferation (1.4-fold, P < 0.02), but did not affect pSTAT5 signaling. Treatment of cells with an Akt1/2 inhibitor or everolimus, which acts on the Akt pathway, reduced Asn492Ile signaling and proliferation to WT levels. Thus, our results identify an association between a gain-of-function PRLR variant and prolactinomas and reveal a new etiology and potential therapeutic approach for these neoplasms

French Endocrine Society Guidance on endocrine side-effects of immunotherapy

The management of cancer patients has changed due to the considerably more frequent use of immune checkpoint inhibitors (ICPI). However, the use of ICPI has a risk of side-effects, particularly endocrine toxicity. Since the indications for ICPI are constantly expanding due to their efficacy, it is important that endocrinologists and oncologists know how to look for this type of toxicity and how to treat it when it arises. In view of this, the French Endocrine Society initiated the formulation of a consensus document on ICPI-related endocrine toxicity. In this paper, we will introduce data on the general pathophysiology of endocrine toxicity, we will then outline expert opinion focusing primarily on methods for screening, management and monitoring for endocrine side-effects in patients treated by ICPI. We will then look in turn at endocrinopathies that are induced by ICPI including dysthyroidism, hypophysitis, primary adrenal insufficiency and fulminant diabetes. In each chapter, expert opinion will be given on the diagnosis, management and monitoring for each complication. These expert opinions will also discuss the methodology for categorizing these side-effects in oncology using \u27Common terminology criteria for adverse events\u27 (CTCAE) and the difficulties in applying this to endocrine side-effects in the case of these anti-cancer therapies. This is shown in particular by certain recommendations that are used for other side-effects (high-dose corticosteroids, contra-indicated in ICPI for example), and that cannot be considered as appropriate in the management of endocrine toxicity, as it usually does not require ICPI withdrawal or high dose glucocorticoid intake

Medical treatment of prolactinomas.

Prolactinomas, the most prevalent type of neuroendocrine disease, account for approximately 40% of all pituitary adenomas. The most important clinical problems associated with prolactinomas are hypogonadism, infertility and hyposexuality. In patients with macroprolactinomas, mass effects, including visual field defects, headaches and neurological disturbances, can also occur. The objectives of therapy are normalization of prolactin levels, to restore eugonadism, and reduction of tumor mass, both of which can be achieved in the majority of patients by treatment with dopamine agonists. Given their association with minimal morbidity, these drugs currently represent the mainstay of treatment for prolactinomas. Novel data indicate that these agents can be successfully withdrawn in a subset of patients after normalization of prolactin levels and tumor disappearance, which suggests the possibility that medical therapy may not be required throughout life. Nevertheless, multimodal therapy that involves surgery, radiotherapy or both may be necessary in some cases, such as patients who are resistant to the effects of dopamine agonists or for those with atypical prolactinomas. This Review reports on efficacy and safety of pharmacotherapy in patients with prolactinomas

Evidence that pain sensitivity is rhythmic in humans, mainly driven by the endogenous circadian system and little by sleep

Abstract Pain intensity has been reported to fluctuate during the day in some experimental and clinical conditions, but the mechanisms underlying these fluctuations are unknown. Although the circadian timing system is known to regulate a wide range of physiological functions, its implication in pain regulation is unknown. We show here, using highly controlled laboratory constant routine conditions, that pain sensitivity is rhythmic over the 24-hours and strongly controlled by the endogenous circadian timing system. We find that pain sensitivity follows a sinusoidal circadian rhythmicity, with a maximum in the middle of the night and a minimum in the afternoon. We also find a weak homeostatic control of pain sensitivity, with a linear increase over the 34 hours of prolonged wakefulness, which parallels that of sleep pressure. Using mathematical modelling, we describe that the circadian system accounts for 80% of the full magnitude of pain sensitivity over the 24 hours, and that sleep-related processes account for only 20%. This result reveals that nocturnal analgesia is predominantly induced by the circadian system and has been wrongly attributed only to sleep. Our findings highlight the need to consider the time of day in pain assessment, and suggest that personalized circadian medicine may be a promising approach to pain management. Significance statement We discovered that sensitivity to pain is rhythmic in healthy humans, that sensitivity is maximal at night and minimal in the afternoon. Contrarily to the current thinking that sleep is the best painkiller, we find that the 24-h rhythmicity of sensitivity to pain is mainly controlled by a biological circadian clock in our body, and very little by our sleep. Our article reveals the neurobiological mechanisms involved in driving the rhythmicity of pain perception in humans, with the main time-piece located in the brain (the suprachiasmatic nuclei in the hypothalamus). Our findings challenge the current vision of pain physiology, and reveal the need to consider time-of-day and internal biological time for pain evaluation and pain management