Laparoscopic versus open approach for interval cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) in advanced epithelial ovarian cancer: a matched comparative study.

BACKGROUND: The use of the laparoscopic approach for the treatment of carcinomatosis from epithelial ovarian cancer (EOC) is controversial. The aim of this study was to compare the short-term outcomes of both laparoscopic and open approach for interval CRS+HIPEC in a matched cohort of patients with advanced EOC. METHODS: A retrospective analysis of a prospectively maintained database including 254 patients treated with interval CRS-HIPEC between January 2016 and December 2021 was performed. Patients with primary disease and limited carcinomatosis (PCI ≤ 10) were selected. A comparative analysis of patients treated by either open (O-CRS-HIPEC) or the laparoscopic (L-CRS-HIPEC) approach was conducted. Overall survival (OS), disease-free survival (DFS), and perioperative outcomes were analysed. RESULTS: Fifty-three patients were finally selected and enrolled into two comparable groups in this study. Of these, 14 patients were treated by interval L-CRS-HIPEC and 39 by interval O-CRS-HIPEC. The L-CRS-HIPEC group had a shorter hospital stay (5.6 ± 1.9 vs. 9.7 ± 9.8 days; p < 0.001) and a shorter time to return to systemic chemotherapy (4.3 ± 1.9 vs. 10.3 ± 16.8 weeks; p = 0.003). There were no significant differences in postoperative complications between both groups. The 2-year OS and DFS was 100% and 62% in the L-CRS-HIPEC group versus 92% and 60% in the O-CRS-HIPEC group, respectively (p = 0.96; p = 0.786). CONCLUSION: This study suggests that the use of interval L-CRS-HIPEC for primary advanced EOC is associated with shorter hospital stay and return to systemic treatment while obtaining similar oncological results compared to the open approach. Further prospective research is needed to recommend this new approach for these strictly selected patients.

Antitumor effect of a small-molecule inhibitor of KRASG12D in xenograft models of mucinous appendicular neoplasms.

Pseudomyxoma peritonei (PMP) is a rare disease characterized by a massive accumulation of mucus in the peritoneal cavity. The only effective treatment is aggressive surgery, aimed at removing all visible tumors. However, a high percentage of patients relapse, with subsequent progression and death. Recently, there has been an increase in therapies that target mutated oncogenic proteins. In this sense, KRAS has been reported to be highly mutated in PMP, with KRASG12D being the most common subtype. Here, we tested the efficacy of a small-molecule KRASG12D inhibitor, MRTX1133, in a high-grade PMP xenograft mouse model carrying a KRASG12D mutation. The results obtained in this work showed a profound inhibition of tumor growth, which was associated with a reduction in cell proliferation, an increase in apoptosis, and a reduction in the MAPK and PI3K/AKT/mTOR signaling pathways. In conclusion, these results demonstrate the high potency and efficacy of MRTX1133 in KRASG12D-PMP tumors and provide a rationale for clinical trials.

Efficacy and Safety of Intraoperative Hyperthermic Intraperitoneal Chemotherapy for Locally Advanced Colon Cancer: A Phase 3 Randomized Clinical Trial.

Importance: Peritoneal metastasis in patients with locally advanced colon cancer (T4 stage) is estimated to recur at a rate of approximately 25% at 3 years from surgical resection and is associated with poor prognosis. There is controversy regarding the clinical benefit of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) in these patients. Objective: To assess the efficacy and safety of intraoperative HIPEC in patients with locally advanced colon cancer. Design, Setting, and Participants: This open-label, phase 3 randomized clinical trial was conducted in 17 Spanish centers from November 15, 2015, to March 9, 2021. Enrolled patients were aged 18 to 75 years with locally advanced primary colon cancer diagnosed preoperatively (cT4N02M0). Interventions: Patients were randomly assigned 1:1 to receive cytoreduction plus HIPEC with mitomycin C (30 mg/m2 over 60 minutes; investigational group) or cytoreduction alone (comparator group), both followed by systemic adjuvant chemotherapy. Randomization of the intention-to-treat population was done via a web-based system, with stratification by treatment center and sex. Main Outcomes and Measures: The primary outcome was 3-year locoregional control (LC) rate, defined as the proportion of patients without peritoneal disease recurrence analyzed by intention to treat. Secondary end points were disease-free survival, overall survival, morbidity, and rate of toxic effects. Results: A total of 184 patients were recruited and randomized (investigational group, n = 89; comparator group, n = 95). The mean (SD) age was 61.5 (9.2) years, and 111 (60.3%) were male. Median duration of follow-up was 36 months (IQR, 27-36 months). Demographic and clinical characteristics were similar between groups. The 3-year LC rate was higher in the investigational group (97.6%) than in the comparator group (87.6%) (log-rank P = .03; hazard ratio [HR], 0.21; 95% CI, 0.05-0.95). No differences were observed in disease-free survival (investigational, 81.2%; comparator, 78.0%; log-rank P = .22; HR, 0.71; 95% CI, 0.41-1.22) or overall survival (investigational, 91.7%; comparator, 92.9%; log-rank P = .68; HR, 0.79; 95% CI, 0.26-2.37). The definitive subgroup with pT4 disease showed a pronounced benefit in 3-year LC rate after investigational treatment (investigational: 98.3%; comparator: 82.1%; log-rank P = .003; HR, 0.09; 95% CI, 0.01-0.70). No differences in morbidity or toxic effects between groups were observed. Conclusions and Relevance: In this randomized clinical trial, the addition of HIPEC to complete surgical resection for locally advanced colon cancer improved the 3-year LC rate compared with surgery alone. This approach should be considered for patients with locally advanced colorectal cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT02614534.

Learning curve for minimal invasive cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) procedures.

PURPOSE: The benefits of the minimally invasive approach for performing cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (L-CRS + HIPEC) have been described previously, associating an early recovery with similar oncologic outcomes in patients with limited peritoneal carcinomatosis. Currently, no studies are focusing on the learning curve for this emerging procedure. This study aimed to evaluate the L-CRS + HIPEC learning curve and its knock-on effect on the perioperative outcomes. METHODS: We identified all consecutive unselected patients who underwent L-CRS + HIPEC by a single surgeon between April 2016 and January 2022 (n = 51). Patients who underwent risk-reducing CRS + HIPEC (PCI = 0) or initial conversion due to an intraoperative PCI > 10 were excluded from the final analysis. To evaluate the learning curve, perioperative data were analysed using the cumulative sum (CUSUM) analysis. RESULTS: Twenty-six patients were included in the final analysis. Major morbidity occurred in one patient (3.8%). The difficulty of the L-CRS + HIPEC procedures was categorised as low in 23.1% (n = 6), intermediate in 19.2% (n = 5), and advanced in 57.7% (n = 15). The mean length of hospital stay was 5.4 ± 1.5 days. No patient had a conversion to open surgery. The learning curve was divided into two distinct phases: the learning phase (1-14) and the consolidation phase (15-26). A significant decrease in the operative time (375 ± 103.1 vs 239.2 ± 63.6 min) was observed with no differences in complexity, the number of peritonectomy procedures, or morbidity. CONCLUSION: L-CRS + HIPEC is a complex procedure that must be performed in a high-volume and experienced oncologic unit, requiring a learning curve to achieve the consolidation condition, which could be established after 14 procedures.

Intraoperative oxygen tension and redox homeostasis in Pseudomyxoma peritonei: A short case series.

Introduction: Pseudomyxoma peritonei (PMP) is a rare malignant disease characterized by a massive multifocal accumulation of mucin within the peritoneal cavity. The current treatment option is based on complete cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy. However, the recurrence is frequent with subsequent progression and death. To date, most of the studies published in PMP are related to histological and genomic analyses. Thus, the need for further studies unveiling the underlying PMP molecular mechanisms is urgent. In this regard, hypoxia and oxidative stress have been extensively related to tumoral pathologies, although their contribution to PMP has not been elucidated. Methods: In this manuscript, we have evaluated, for the first time, the intratumoral real-time oxygen microtension (pO2mt) in the tumor (soft and hard mucin) and surrounding healthy tissue from five PMP patients during surgery. In addition, we measured hypoxia (Hypoxia Inducible Factor-1a; HIF-1α) and oxidative stress (catalase; CAT) markers in soft and hard mucin from the same five PMP patient samples and in five control samples. Results: The results showed low intratumoral oxygen levels, which were associated with increased HIF-1α protein levels, suggesting the presence of a hypoxic environment in these tumors. We also found a significant reduction in CAT activity levels in soft and hard mucin compared with healthy tissue samples. Discussion: In conclusion, our study provides the first evidence of low intratumoral oxygen levels in PMP patients associated with hypoxia and oxidative stress markers. However, further investigation is required to understand the potential role of oxidative stress in PMP in order to find new therapeutic strategies.

Intraoperative metabolic changes associated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

BACKGROUND: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) causes considerable hemodynamic, respiratory, and metabolic changes during the perioperative period. OBJECTIVES: To evaluate metabolic changes associated with this procedure. Understanding perioperative factors and their association with morbidity may improve the perioperative management of patients undergoing this treatment. METHODS: A retrospective review of a prospectively maintained database was performed. All consecutive unselected patients who underwent CRS plus HIPEC between January 2018 and December 2020 (n = 219) were included. RESULTS: The mean age was 58 ± 11.7 years and 167 (76.3%) were female. The most frequent histology diagnosis was serous ovarian carcinoma 49.3% (n = 108) and colon carcinoma 36.1% (n = 79). Mean peritoneal cancer index was 14.07 ± 10.47. There were significant variations in pH, lactic acid, sodium, potassium, glycemia, bicarbonate, excess bases, and temperature (p < 0.05) between the pre-HIPEC and post-HIPEC periods. The closed HIPEC technique resulted in higher levels of temperature than the open technique (p < 0.05). Age, potassium level post-HIPEC potassium level, and pre-HIPEC glycemia were identified as prognostic factors for morbidity in multivariate analysis. CONCLUSION: The administration of HIPEC after CRS causes significant changes in internal homeostasis. Although the closed technique causes a greater increase in temperature, it is not related to higher morbidity rates. The patient's age, post-HIPEC potassium level, and pre-HIPEC glycemia are predictive factors for morbidity.

The Role of Intraperitoneal Intraoperative Chemotherapy with Paclitaxel in the Surgical Treatment of Peritoneal Carcinomatosis from Ovarian Cancer-Hyperthermia versus Normothermia: A Randomized Controlled Trial.

BACKGROUND: The treatment of ovarian carcinomatosis with cytoreductive surgery and HIPEC is still controversial. The effect and pharmacokinetics of the chemotherapeutics used (especially taxanes) are currently under consideration. METHODS: A phase II, simple blind and randomized controlled trial (NTC02739698) was performed. The trial included 32 patients with primary or recurrent ovarian carcinomatosis undergoing cytoreductive surgery (CRS) and intraoperative intraperitoneal chemotherapy with paclitaxel (PTX): 16 in hyperthermic (42-43 °C) and 16 in normothermic (37 °C) conditions. Tissue, serum and plasma samples were taken in every patient before and after intraperitoneal chemotherapy to measure the concentration of PTX. To analyze the immunohistochemical profile of p53, p27, p21, ki67, PCNA and caspase-3 and the pathological response, a scale of intensity and percentage of expression and a grouped Miller and Payne system were used, respectively. Perioperative characteristics and morbi-mortality were also analyzed. RESULTS: The main characteristics of patients, surgical morbidity, hemotoxicity and nephrotoxicity were similar in both groups. The concentration of paclitaxel in the tissue was higher than that observed in plasma and serum, although no statistically significant differences were found between the two groups. No statistically significant association regarding pathological response and apoptosis (caspase-3) between both groups was proved. There were no statistically significant differences between the normothermic and the hyperthermic group for pathological response and apoptosis. CONCLUSIONS: The use of intraperitoneal PTX has proven adequate pharmacokinetics with reduction of cell cycle and proliferation markers globally without finding statistically significant differences between its administration under hyperthermia versus normothermia conditions.

Connecting nutritional deprivation and pubertal inhibition via GRK2-mediated repression of kisspeptin actions in GnRH neurons.

BACKGROUND: Perturbations in the timing of puberty, with potential adverse consequences in later health, are increasingly common. The underlying neurohormonal mechanisms are unfolded, but nutritional alterations are key contributors. Efforts to unveil the basis of normal puberty and its metabolic control have focused on mechanisms controlling expression of Kiss1, the gene encoding the puberty-activating neuropeptide, kisspeptin. However, other regulatory phenomena remain ill-defined. Here, we address the putative role of the G protein-coupled-receptor kinase-2, GRK2, in GnRH neurons, as modulator of pubertal timing via repression of the actions of kisspeptin, in normal maturation and conditions of nutritional deficiency. METHODS: Hypothalamic RNA and protein expression analyses were conducted in maturing female rats. Pharmacological studies involved central administration of GRK2 inhibitor, ßARK1-I, and assessment of gonadotropin responses to kisspeptin or phenotypic and hormonal markers of puberty, under normal nutrition or early subnutrition in female rats. In addition, a mouse line with selective ablation of GRK2 in GnRH neurons, aka G-GRKO, was generated, in which hormonal responses to kisspeptin and puberty onset were monitored, in normal conditions and after nutritional deprivation. RESULTS: Hypothalamic GRK2 expression increased along postnatal maturation in female rats, especially in the preoptic area, where most GnRH neurons reside, but decreased during the juvenile-to-pubertal transition. Blockade of GRK2 activity enhanced Ca+2 responses to kisspeptin in vitro, while central inhibition of GRK2 in vivo augmented gonadotropin responses to kisspeptin and advanced puberty onset. Postnatal undernutrition increased hypothalamic GRK2 expression and delayed puberty onset, the latter being partially reversed by central GRK2 inhibition. Conditional ablation of GRK2 in GnRH neurons enhanced gonadotropin responses to kisspeptin, accelerated puberty onset, and increased LH pulse frequency, while partially prevented the negative impact of subnutrition on pubertal timing and LH pulsatility in mice. CONCLUSIONS: Our data disclose a novel pathway whereby GRK2 negatively regulates kisspeptin actions in GnRH neurons, as major regulatory mechanism for tuning pubertal timing in nutritionally-compromised conditions.

A Proposal for Modification of the PSOGI Classification According to the Ki-67 Proliferation Index in Pseudomyxoma Peritonei.

BACKGROUND: Pseudomyxoma peritonei (PMP) is a rare malignancy, classified according to the Peritoneal Surface Oncology Group International (PSOGI) classification, whose response to treatment remains highly heterogeneous within the high-grade (HG) category. Molecular profiling of PMP cases might help to better categorize patients and predict treatment responses. METHODS: We studied the Ki-67 proliferation rate and P53 overexpression in tissue samples from our historical cohort of HG-PMP patients. We established as cut-off levels the third quartile of each marker to perform univariate and multivariate Cox regression survival analyses. According to these results, the HG-PMP category was divided into subcategories and a new survival analysis was performed. RESULTS: A total of 90/117 patients with PMP undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) were selected for secondary analysis. The survival analysis of the HG-PMP category for preoperative variables showed that a proliferation index defined by Ki-67 >15% is a bad prognostic factor, with a hazard ratio (HR) of 3.20 (95% confidence interval [CI] 1.24-8.25). Accordingly, the HG-PMP group was divided using the Ki-67 15% cut-off. The new PSOGI/Ki-67 variable was an independent prognostic factor for overall survival (OS), with an HR of 3.74 (95% CI 1.88-7.47), and disease-free survival (DFS), with an HR of 4.184 (95% CI 1.79-9.75). The estimated 5-year OS rate was 100%, 70% and 24% for the LG-PMP, HG-PMP ≤15% and HG-PMP >15% groups, respectively (p = 0.0001), while the 5-year DFS rate was 90%, 44% and 0%, respectively (p = 0.0001). CONCLUSION: Division of the HG-PMP category of the PSOGI classification, according to the Ki-67 proliferation index, provides two well-defined subcategories, with significant differences in terms of OS and DFS, and hence high prognostic value.

Molecular diagnosis of polycystic ovary syndrome in obese and non-obese women by targeted plasma miRNA profiling.

OBJECTIVE: Polycystic ovary syndrome (PCOS) is diagnosed based on the clinical signs, but its presentation is heterogeneous and potentially confounded by concurrent conditions, such as obesity and insulin resistance. miRNA have recently emerged as putative pathophysiological and diagnostic factors in PCOS. However, no reliable miRNA-based method for molecular diagnosis of PCOS has been reported. The aim of this study was to develop a tool for accurate diagnosis of PCOS by targeted miRNA profiling of plasma samples, defined on the basis of unbiased biomarker-finding analyses and biostatistical tools. METHODS: A case-control PCOS cohort was cross-sectionally studied, including 170 women classified into four groups: non-PCOS/lean, non-PCOS/obese, PCOS/lean, and PCOS/obese women. High-throughput miRNA analyses were performed in plasma, using NanoString technology and a 800 human miRNA panel, followed by targeted quantitative real-timePCR validation. Statistics were applied to define optimal normalization methods, identify deregulated biomarker miRNAs, and build classification algorithms, considering PCOS and obesity as major categories. RESULTS: The geometric mean of circulating hsa-miR-103a-3p, hsa-miR-125a-5p, and hsa-miR-1976, selected among 125 unchanged miRNAs, was defined as optimal reference for internal normalization (named mR3-method). Ten miRNAs were identified and validated after mR3-normalization as differentially expressed across the groups. Multinomial least absolute shrinkage and selection operator regression and decision-tree models were built to reliably discriminate PCOS vs non-PCOS, either in obese or non-obese women, using subsets of these miRNAs as performers. CONCLUSIONS: We define herein a robust method for molecular classification of PCOS based on unbiased identification of miRNA biomarkers and decision-tree protocols. This method allows not only reliable diagnosis of non-obese women with PCOS but also discrimination between PCOS and obesity. CAPSULE: We define a novel protocol, based on plasma miRNA profiling, for molecular diagnosis of PCOS. This tool not only allows proper discrimination of the condition in non-obese women but also permits distinction between PCOS and obesity, which often display overlapping clinical presentations.

Physical comorbidities as a marker for high risk of psychological distress in cancer patients.

AIMS: Physical and psychiatric comorbidities are common in cancer patients and could impact their treatment and prognosis. However, the evidence base regarding the influence of comorbidities in the management and health service use of patients is still scant. In this research we investigated how physical comorbidities are related to the mental health and help-seeking of cancer patients. METHODS: Data were obtained from the representative National Health Survey of Spain (2017). Participants were respondents who reported a cancer diagnosis (n = 484). These were also matched with controls without cancer history (n = 484) based on age, gender, and region. Four alternative physical comorbidities indices were created based on information regarding 28 chronic conditions. Outcomes of interest were psychological distress and having consulted a mental healthcare professional in the year before the survey. RESULTS: Thirty percent of cancer patients reported significant psychological distress but only 10% had consulted a professional. After adjusting for sociodemographic variables, among cancer patients each additional comorbidity was associated with 9% higher odds of reporting high psychological distress (odds ratio [OR] = 1.09, 95% confidence interval [CI]: 1.01-1.16) and 21% higher odds of having consulted a mental healthcare professional (OR = 1.21, 95% CI: 1.09-1.34). The effects of comorbidities depended on the type of index and were different in controls without cancer history. CONCLUSION: Physical comorbidities in cancer patients are associated with higher risk of psychological distress and higher demand for mental health services. We encourage further research on this issue as it could improve mental health screening and management in oncologic care.

From the Ronnett to the PSOGI Classification System for Pseudomyxoma Peritonei: A Validation Study.

BACKGROUND: Several classifications have been used for pseudomyxoma peritonei (PMP), and among these, the Ronnett classification is the most commonly used. However, a new consensual Peritoneal Surface Oncology Group International (PSOGI) classification has recently been proposed. Nonetheless, to date, the ability of the PSOGI classification to predict survival based on its different disease histologic categories has not been validated. METHODS: This study enrolled 117 patients with PMP who had undergone cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) between 1997 and 2020. Cox proportional hazards regression models and time-dependent curve receiver operating characteristic (ROC) analyses were used to assess the predictive capacity of both classification systems for the overall survival (OS) and disease-free survival (DFS) of these patients. RESULTS: Significant differences in the 5-year OS rate were found for the different histologic grades according to each of the classifications. The completeness of cytoreduction score (CCS) was identified as a factor that predicted patient OS prognosis (p = 0.006). According to the time-dependent ROC curves at the "100" time point, adjusted by the CCS and DFS, the capacity to predict OS was optimal and achieved an area under the curve (AUC) of about 69% for OS and approximately 62% for DFS. CONCLUSIONS: Both the Ronnett and PSOGI classifications were able to predict survival optimally for this patient cohort. However, when the classifications were adjusted by the CCS, the predictive availability for OS was better with the PSOGI classification than with the Ronnett classification.

Congenital ablation of Tacr2 reveals overlapping and redundant roles of NK2R signaling in the control of reproductive axis.

Tachykinin (TAC) signaling is an important element in the central control of reproduction. TAC family is mainly composed of substance P (SP), neurokinin A (NKA), and NKB, which bind preferentially to NK1, NK2, and NK3 receptors, respectively. While most studies have focused on the reproductive functions of NKB/NK3R, and to a lesser extent SP/NK1R, the relevance of NK2R, encoded by Tacr2, remains poorly characterized. Here, we address the physiological roles of NK2R in regulating the reproductive axis by characterizing a novel mouse line with congenital ablation of Tacr2. Activation of NK2R evoked acute luteinizing hormone (LH) responses in control mice, similar to those of agonists of NK1R and NK3R. Despite the absence of NK2R, Tacr2-/- mice displayed only partially reduced LH responses to an NK2R agonist, which, nonetheless, were abrogated after blockade of NK3R in Tacr2-/- males. While Tacr2-/- mice displayed normal pubertal timing, LH pulsatility was partially altered in Tacr2-/- females in adulthood, with suppression of basal LH levels, but no changes in the number of LH pulses. In addition, trends for increase in breeding intervals were detected in Tacr2-/- mice. However, null animals of both sexes were fertile, with no changes in estrous cyclicity or sex preference in social behavioral tests. In conclusion, stimulation of NK2R elicited LH responses in mice, while congenital ablation of Tacr2 partially suppressed basal and stimulated LH secretion, with moderate reproductive impact. Our data support a modest, albeit detectable, role of NK2R in the control of the gonadotropic axis, with partially overlapping and redundant functions with other tachykinin receptors.NEW & NOTEWORTHY We have explored here the impact of congenital ablation of the gene (Tacr2) encoding the tachykinin receptor, NK2R, in terms of neuroendocrine control of the reproductive axis, using a novel Tacr2 KO mouse line. Our data support a modest, albeit detectable, role of NK2R in the control of the gonadotropic axis, with partially overlapping and redundant functions with other tachykinin receptors.

Gonadal hormone-dependent vs. -independent effects of kisspeptin signaling in the control of body weight and metabolic homeostasis.

BACKGROUND: Kisspeptins, encoded by Kiss1, have emerged as essential regulators of puberty and reproduction by primarily acting on GnRH neurons, via their canonical receptor, Gpr54. Mounting, as yet fragmentary, evidence strongly suggests that kisspeptin signaling may also participate in the control of key aspects of body energy and metabolic homeostasis. However, characterization of such metabolic dimension of kisspeptins remains uncomplete, without an unambiguous discrimination between the primary metabolic actions of kisspeptins vs. those derived from their ability to stimulate the secretion of gonadal hormones, which have distinct metabolic actions on their own. In this work, we aimed to tease apart primary vs. secondary effects of kisspeptins in the control of key aspects of metabolic homeostasis using genetic models of impaired kisspeptin signaling and/or gonadal hormone status. METHODS: Body weight (BW) gain and composition, food intake and key metabolic parameters, including glucose tolerance, were comparatively analyzed, in lean and obesogenic conditions, in mice lacking kisspeptin signaling due to global inactivation of Gpr54 (displaying profound hypogonadism; Gpr54-/-) vs. Gpr54 null mice with selective re-introduction of Gpr54 expression only in GnRH cells (Gpr54-/-Tg), where kisspeptin signaling elsewhere than in GnRH neurons is ablated but gonadal function is preserved. RESULTS: In male mice, global elimination of kisspeptin signaling resulted in decreased BW, feeding suppression and increased adiposity, without overt changes in glucose tolerance, whereas Gpr54-/- female mice displayed enhanced BW gain at adulthood, increased adiposity and perturbed glucose tolerance, despite reduced food intake. Gpr54-/-Tg rescued mice showed altered postnatal BW gain in males and mildly perturbed glucose tolerance in females, with intermediate phenotypes between control and global KO animals. Yet, body composition and leptin levels were similar to controls in gonadal-rescued mice. Exposure to obesogenic insults, such as high fat diet (HFD), resulted in exaggerated BW gain and adiposity in global Gpr54-/- mice of both sexes, and worsening of glucose tolerance, especially in females. Yet, while rescued Gpr54-/-Tg males displayed intermediate BW gain and feeding profiles and impaired glucose tolerance, rescued Gpr54-/-Tg females behaved as controls, except for a modest deterioration of glucose tolerance after ovariectomy. CONCLUSION: Our data support a global role of kisspeptin signaling in the control of body weight and metabolic homeostasis, with a dominant contribution of gonadal hormone-dependent actions. However, our results document also discernible primary effects of kisspeptin signaling in the regulation of body weight gain, feeding and responses to obesogenic insults, which occur in a sexually-dimorphic manner. SUMMARY OF TRANSLATIONAL RELEVANCE: Kisspeptins, master regulators of reproduction, may also participate in the control of key aspects of body energy and metabolic homeostasis; yet, the nature of such metabolic actions remains debatable, due in part to the fact that kisspeptins modulate gonadal hormones, which have metabolic actions on their own. By comparing the metabolic profiles of two mouse models with genetic inactivation of kisspeptin signaling but different gonadal status (hypogonadal vs. preserved gonadal function), we provide herein a systematic dissection of gonadal-dependent vs. -independent metabolic actions of kisspeptins. Our data support a global role of kisspeptin signaling in the control of body weight and metabolic homeostasis, with a dominant contribution of gonadal hormone-dependent actions. However, our results document also discernible primary effects of kisspeptin signaling in the regulation of body weight gain, feeding and responses to obesogenic insults, which occur in a sexually-dimorphic manner. These data pave the way for future analyses addressing the eventual contribution of altered kisspeptin signaling in the development of metabolic alterations, especially in conditions linked to reproductive dysfunction.

Deregulation of miR-324/KISS1/kisspeptin in early ectopic pregnancy: mechanistic findings with clinical and diagnostic implications.

BACKGROUND: Ectopic pregnancy is a life-threatening condition for which novel screening tools that would enable early accurate diagnosis would improve clinical outcomes. Kisspeptins, encoded by KISS1, play an essential role in human reproduction, at least partially by regulating placental function and possibly embryo implantation. Kisspeptin levels are elevated massively in normal pregnancy and reportedly altered in various gestational pathologic diseases. Yet, the pathophysiologic role of KISS1/kisspeptin in ectopic pregnancy has not been investigated previously. OBJECTIVE: The purpose of this study was to evaluate changes of KISS1/kisspeptin levels in ectopic pregnancy and their underlaying molecular mechanisms and to ascertain the diagnostic implications of these changes. STUDY DESIGN: A total of 122 women with normal pregnancy who underwent voluntary termination of pregnancy and 84 patients who experienced tubal ectopic pregnancy were recruited. Measurements of plasma kisspeptins and KISS1 expression analyses in human embryonic/placental tissue were conducted in ectopic pregnancy and voluntary termination of pregnancy control subjects during the early gestational window (<12 weeks). Putative microRNA regulators of KISS1 were predicted in silico, followed by expression analyses of selected microRNAs and validation of repressive interactions in vitro. Circulating levels of these microRNAs were also assayed in ectopic pregnancy vs voluntary termination of pregnancy. RESULTS: Circulating kisspeptins gradually increased during the first trimester of normal pregnancy but were reduced markedly in ectopic pregnancy. This profile correlated with the expression levels of KISS1 in human embryonic/placental tissue, which increased in voluntary termination of pregnancy but remained suppressed in ectopic pregnancy. Bioinformatic predictions and expression analyses identified miR-27b-3p and miR-324-3p as putative repressors of KISS1 in human embryonic/placental tissue at <12 weeks gestation, when expression of microRNAs was low in voluntary termination of pregnancy control subjects but significantly increased in ectopic pregnancy. Yet, a significant repressive interaction was documented only for miR-324-3p, occurring at the predicted 3'-UTR of KISS1. Interestingly, circulating levels of miR-324-3p, but not of miR-27b-3p, were suppressed distinctly in ectopic pregnancy, despite elevated tissue expression of the pre-microRNA. A decision-tree model that used kisspeptin and miR-324-3p levels was successful in discriminating ectopic pregnancy vs voluntary termination of pregnancy, with a receiver-operating characteristic area under the curve of 0.95±0.02 (95% confidence interval). CONCLUSION: Our results document a significant down-regulation of KISS1/kisspeptins in early stages of ectopic pregnancy via, at least partially, a repressive interaction with miR-324-3p. Our data identify circulating kisspeptins and miR-324-3p as putative biomarkers for accurate screening of ectopic pregnancy at early gestational ages.

Sex-Biased Physiological Roles of NPFF1R, the Canonical Receptor of RFRP-3, in Food Intake and Metabolic Homeostasis Revealed by its Congenital Ablation in mice.

BACKGROUND: RF-amide-related peptide-3 (RFRP-3), the mammalian ortholog of gonadotropin-inhibiting hormone, operates as inhibitory signal for the reproductive axis. Recently, RFRP-3 has been also suggested to stimulate feeding, and therefore might contribute to the control of body weight and its alterations. Yet, characterization of the metabolic actions of RFRP-3 has been so far superficial and mostly pharmacological. Here, we aim to investigate the physiological roles of RFRP-3 signaling in the control of feeding and metabolic homeostasis using a novel mouse model of genetic ablation of its canonical receptor, NPFF1R. METHODS: Food intake, body weight gain and composition, and key metabolic parameters, including glucose tolerance and insulin sensitivity, were monitored in mice with constitutive inactivation of NPFF1R. RESULTS: Congenital elimination of NPFF1R in male mice resulted in changes in feeding patterns, with a decrease in spontaneous food intake and altered responses to leptin and ghrelin: leptin-induced feeding suppression was exaggerated in NPFF1R null mice, whereas orexigenic responses to ghrelin were partially blunted. Concordant with this pro-anorectic phenotype, hypothalamic expression of Pomc was increased in NPFF1R null mice. In contrast, spontaneous feeding and neuropeptide expression remained unaltered in NPFF1R KO female mice. Despite propensity for reduced feeding, ablation of NPFF1R signaling in male mice did not cause overt alterations in body weight (BW) gain or composition, neither it affected BW responses to high fat diet (HFD), total energy expenditure or RQ ratios. Yet, NPFF1R KO males showed a decrease in locomotor activity. Conversely, NPFF1R null female mice tended to be heavier and displayed exaggerated BW increases in response to obesogenic insults, such as HFD or ovariectomy. These were associated to increased fat mass, decreased total energy expenditure in HFD, and unaltered RQ ratios or spontaneous locomotor activity. Finally, lack of NPFF1R signaling worsened the metabolic impact of HFD on glycemic homeostasis in males, as revealed by impaired glucose tolerance and insulin sensitivity, while female mice remained unaffected. CONCLUSION: Our data support a discernible orexigenic role of NPFF1R signaling selectively in males, which might modulate the effects of leptin and ghrelin on food intake. In addition, our study is the first to disclose the sex-biased, deleterious impact of the lack of NPFF1R signaling on body weight and fat composition, energy expenditure, locomotor activity and glucose balance, which exaggerates some of the metabolic consequences of concurrent obesogenic insults, such as HFD, in a sexually dimorphic manner. SUMMARY OF TRANSLATIONAL RELEVANCE: Our data are the first to document the nature and magnitude of the regulatory actions of RFRP-3/NPFF1R signaling in the control of feeding and metabolic homeostasis in a physiological setting. Our results not only suggest an orexigenic action of endogenous RFRP-3, specifically in males, but reveal also the detrimental impact of ablation of NPFF1R signaling on body composition, energy expenditure, locomotor activity or glucose balance, especially when concurrent with other obesogenic insults, as HFD, thereby providing the first evidence for additional metabolic effects of RFRP-3, other that the mere control of feeding. Interestingly, alterations of such key metabolic parameters occurred in a sex-biased manner, with males being more sensitive to deregulation of locomotor activity and glycemic control, while females displayed clearer obesogenic responses and deregulated energy expenditure. While our study cannot discard the possibility of RFRP-3 actions via alternative pathways, such as NPFF2R, our data pave the way for future analyses addressing the eventual contribution of altered RFRP-3/NPFF1R signaling in the development of metabolic alterations (including obesity and its comorbidities), especially in conditions associated to reproductive dysfunction.