Real-World Impact of Adjuvant Anti-HER2 Treatment on Characteristics and Outcomes of Women With HER2-Positive Metastatic Breast Cancer in the ESME Program.

BACKGROUND: Although adjuvant cancer treatments increase cure rates, they may induce clonal selection and tumor resistance. Information still lacks as whether (neo)adjuvant anti-HER2 treatments impact the patterns of recurrence and outcomes of HER2-positive (HER2+) metastatic breast cancer (MBC). We aimed to assess this in the large multicenter ESME real-world database. PATIENTS AND METHODS: We examined the characteristics and outcomes (overall survival (OS) and progression-free survival under first-line treatment (PFS1)) of HER2+ patients with MBC from the French ESME program with recurrent disease, as a function of the previous receipt of adjuvant trastuzumab. Multivariable analyses used Cox models adjusted for baseline demographic, prognostic factors, adjuvant treatment received, and disease-free interval. RESULTS: Two thousand one hundred and forty-three patients who entered the ESME cohort between 2008 and 2017 had a recurrent HER2+ MBC. Among them, 56% had received (neo)adjuvant trastuzumab and 2.5% another anti-HER2 in this setting. Patients pre-exposed to trastuzumab were younger, had a lower disease-free interval, more HR-negative disease and more metastatic sites. While the crude median OS appeared inferior in patients exposed to adjuvant trastuzumab, as compared to those who did not (37.2 (95%CI 34.4-40.3) versus 53.5 months (95% CI: 47.6-60.1)), this difference disappeared in the multivariable model (HR = 1.05, 95%CI 0.91-1.22). The same figures were observed for PFS1. CONCLUSIONS: Among patients with relapsed HER2+ MBC, the receipt of adjuvant trastuzumab did not independently predict for worse outcomes when adjusted to other prognostic factors.

Impact of breast cancer molecular subtypes on the incidence, kinetics and prognosis of central nervous system metastases in a large multicentre real-life cohort.

BACKGROUND: Metastatic breast cancer (MBC) behaviour differs depending on hormone receptors (HR) and human epidermal growth factor receptor (HER2) statuses. METHODS: The kinetics of central nervous system (CNS) metastases (CNS metastasis-free survival, CNSM-FS) and subsequent patient's prognosis (overall survival, OS) according to the molecular subtype were retrospectively assessed in 16703 MBC patients of the ESME nationwide multicentre MBC database (Kaplan-Meier method). RESULTS: CNS metastases occurred in 4118 patients (24.6%) (7.2% at MBC diagnosis and 17.5% later during follow-up). Tumours were HER2-/HR+ (45.3%), HER2+/HR+ (14.5%), HER2+/HR- (14.9%) and triple negative (25.4%). Median age at CNS metastasis diagnosis was 58.1 years (range: 22.8-92.0). The median CNSM-FS was 10.8 months (95% CI: 16.5-17.9) among patients who developed CNS metastases. Molecular subtype was independently associated with CNSM-FS (HR = 3.45, 95% CI: 3.18-3.75, triple-negative and HER2-/HR+ tumours). After a 30-month follow-up, median OS after CNS metastasis diagnosis was 7.9 months (95% CI: 7.2-8.4). OS was independently associated with subtypes: median OS was 18.9 months (HR = 0.57, 95% CI: 0.50-0.64) for HER2+/HR+ , 13.1 months (HR = 0.72, 95% CI: 0.65-0.81) for HER2+/HR-, 4.4 months (HR = 1.55, 95% CI: 1.42-1.69) for triple-negative and 7.1 months for HER2-/HR+ patients (p <0.0001). CONCLUSIONS: Tumour molecular subtypes strongly impact incidence, kinetics and prognosis of CNS metastases in MBC patients. CLINICAL TRIAL REGISTRATION: NCT03275311.

Obesity alters the gustatory perception of lipids in the mouse: plausible involvement of lingual CD36.

A relationship between orosensory detection of dietary lipids, regulation of fat intake, and body mass index was recently suggested. However, involved mechanisms are poorly understood. Moreover, whether obesity can directly modulate preference for fatty foods remains unknown. To address this question, exploration of the oral lipid sensing system was undertaken in diet-induced obese (DIO) mice. By using a combination of biochemical, physiological, and behavioral approaches, we found that i) the attraction for lipids is decreased in obese mice, ii) this behavioral change has an orosensory origin, iii) it is reversed in calorie-restricted DIO mice, revealing an inverse correlation between fat preference and adipose tissue size, iv) obesity suppresses the lipid-mediated downregulation of the lipid-sensor CD36 in circumvallate papillae, usually found during the refeeding of lean mice, and v) the CD36-dependent signaling cascade controlling the intracellular calcium levels ([Ca(2+)]i) in taste bud cells is decreased in obese mice. Therefore, obesity alters the lipid-sensing system responsible for the oral perception of dietary lipids. This phenomenon seems to take place through a CD36-mediated mechanism, leading to changes in eating behavior.

Long-Term Results with Everolimus in Advanced Hormone Receptor Positive Breast Cancer in a Multicenter National Real-World Observational Study.

Everolimus is the first oral targeted therapy widely used in advanced HR+/HER2- breast cancer. We sought to evaluate the impact of everolimus-based therapy on overall survival in the ESME-MBC database, a national metastatic breast cancer cohort that collects retrospective data using clinical trial-like methodology including quality assessments. We compared 1693 patients having received everolimus to 5928 patients not exposed to everolimus in the same period. Overall survival was evaluated according to treatment line, and a propensity score with the inverse probability of treatment weighting method was built to adjust for differences between groups. Crude and landmark overall survival analyses were all compatible with a benefit from everolimus-based therapy. Adjusted hazard ratios for overall survival were 0.34 (95% CI: 0.16-0.72, p = 0.0054), 0.34 (95% CI: 0.22-0.52, p < 0.0001), and 0.23 (95% CI: 0.14-0.36, p < 0.0001) for patients treated with everolimus in line 1, 2, and 3 and beyond, respectively. No clinically relevant benefit on progression-free survival was observed. Causes for everolimus discontinuation were progressive disease (56.2%), adverse events (27.7%), and other miscellaneous reasons. Despite the limitations inherent to such retrospective studies, these results suggest that adding everolimus-based therapy to the therapeutic sequences in patients with advanced HR+/HER2- breast cancer may favorably affect overall survival.

Real-world clinical and survival outcomes of patients with early relapsed triple-negative breast cancer from the ESME national cohort.

BACKGROUND: Early metastatic relapse of triple-negative breast cancer (mTNBC) after anthracyclins and/or taxanes based (A/T) primary treatment represents a highly aggressive cancer situation requiring urgent characterisation and handling. Epidemio-Strategy-Medico-Economical-Metastatic Breast Cancer (ESME-MBC) database, a multicenter, national, observational cohort (NCT03275311) provides recent data on this entity. METHODS: All ESME patients diagnosed between 2008 and 2020 with mTNBC occurring as a relapse after a systemic neoadjuvant/adjuvant taxane and/or anthracycline-based chemotherapy were included. Early relapses were defined by a metastatic diagnosis up to 12 months of the end of neo/adjuvant A/T chemotherapy. We assessed overall survival (OS) and progression-free-survival under first-line treatment (PFS1) by early versus late relapse (≥12 months). RESULTS: Patients with early relapse (N = 881, 46%) were younger and had a larger tumour burden at primary diagnosis than those with late relapses (N = 1045). Early relapse rates appeared stable over time. Median OS was 10.1 months (95% CI 9.3-10.9) in patients with early relapse versus 17.1 months (95% CI 15.7-18.2) in those with late relapse (adjusted hazard-ratio (aHR): 1.92 (95% CI 1.73-2.13); p < 0.001). The median PFS1 was respectively 3.1 months (95% CI 2.9-3.4) and 5.3 months (95% CI 5.1-5.8); (aHR: 1.66; [95% CI 1.50-1.83]; p < 0.001). Among early relapsed patients, a higher number of metastatic sites, visceral disease but not treatment types, were independently associated with a poorer OS. CONCLUSION: These real-world data provide strong evidence on the dismal prognosis, higher treatment resistance and major unmet medical need associated with early relapsed mTNBC. Database registration: clinicaltrials.gov Identifier NCT032753.

Lipid-mediated release of GLP-1 by mouse taste buds from circumvallate papillae: putative involvement of GPR120 and impact on taste sensitivity.

Glucagon-like peptide-1 (GLP-1) signaling modulates sweet-taste sensitivity in the mouse. Because circumvallate papillae (CVPs) express both GLP-1 and its receptor, a local regulation has been suggested. However, whether dietary lipids are involved in this regulation, as shown in the gut, is unknown. By using a combination of biochemical, immunohistochemical, and behavioral approaches, the present data i) confirm the role of GLP-1 signaling in the attraction for sucrose, ii) demonstrate that minute quantities of long-chain FAs (LCFAs) reinforce the attraction for sucrose in a GLP-1 receptor-dependent manner, iii) suggest an involvement of the LCFA receptor GPR120 expressed in taste buds in this system, and iv) support the existence of a regulation by GLP-1 of the lipid sensing mediated by lingual CD36. Therefore, oro-sensory detection of LCFAs may affect sweet and fatty taste responsiveness by controlling the secretion of lingual GLP-1. This regulatory loop, probably triggered by the LCFA-GPR120 interaction, might contribute to the high palatability of foods rich both in fat and sugar.

Association of Endocrine Therapy for HR+/ERBB2+ Metastatic Breast Cancer With Survival Outcomes.

Importance: Evidence suggests that patients with human epidermal growth factor receptor 2-positive (ERBB2+ [formerly HER2+]) metastatic breast cancer (MBC) have different clinical characteristics and outcomes according to their hormone receptor (HR) status. The place of endocrine therapy (ET) for patients with HR+/ERBB2+ is still not clearly defined in this setting. Objective: To evaluate the association of HR status and first-line inclusion of ET with outcomes among patients with ERBB2+ MBC. Design, Setting, and Participants: This cohort study was an analysis of clinical data from the French clinical Epidemiological Strategy and Medical Economics (ESME) cohort, including patients with MBC who started treatment between 2008 and 2017. The last date of follow-up was June 18, 2020. Data were analyzed from May 2021 to May 2022. Exposures: Patients were treated with first-line ERBB2-targeted therapy and either chemotherapy (CT) with or without ET or ET alone. For the study of the association of maintenance ET with outcomes, we included patients treated with first-line ERBB2-targeted therapy with CT and with or without maintenance ET. Main Outcomes and Measures: Median overall survival (OS) and median first-line progression-free survival (PFS) were reported using the Kaplan-Meier method. Cox proportional hazards models and a propensity score were constructed to report and adjust for prognostic factors. Multivariable analysis included age at MBC, time to MBC, number of metastatic sites, type of metastases, and Eastern Cooperative Oncology Group performance status. Results: Among 4145 women with ERBB2+ MBC, 2696 patients had HR+ (median [IQR] age, 58.0 [47.0-67.0] years) and 1449 patients had HR- (56.0 [47.0-64.0] years) tumors. The median OS for patients with HR+ vs HR- tumors was 55.9 months (95% CI, 53.7-59.4 months) vs 42.0 months (95% CI, 38.8-45.2 months), confirmed in multivariable analysis (hazard ratio, 1.40; 95% CI, 1.26-1.56; P < .001). The median PFS for patients with HR+ vs HR- tumors was 12.2 months (95% CI, 11.5-12.9 months) vs 9.8 months (95% CI, 9.2-11.0 months; P = .01), and the HR was 1.15 (95% CI, 1.06-1.26; P < .001). In multivariable analysis, no significant difference was found in OS or PFS for 1520 patients treated with ERBB2-targeted therapy with CT and with or without ET vs 203 patients receiving ERBB2-targeted therapy with ET, regardless of type of ERBB2-targeted therapy (trastuzumab or trastuzumab with pertuzumab). This result was confirmed by matching patients using a propensity score. Using the time-dependent ET variable among patients with ERBB2-targeted therapy with CT, those with maintenance ET had significantly better PFS (hazard ratio, 0.70; 95% CI, 0.60-0.82; P < .001) and OS (hazard ratio, 0.47; 95% CI, 0.39-0.57; P < .001). Conclusions and Relevance: These results suggest that ET-containing first-line regimens may be associated with benefits among a subgroup of patients with HR+/ERBB2+ MBC.

Clinicopathological characteristics and prognosis of breast cancer patients with isolated central nervous system metastases in the multicentre ESME database.

BACKGROUND: As a result of progress in diagnosis and treatment, there is a growing prevalence of metastatic breast cancer (MBC) with isolated CNS metastases. This study describes the largest-to-date real-life cohort of this clinical setting and compares it to other clinical presentations. METHODS: We retrospectively analysed the French Epidemiological Strategy and Medical Economics (ESME) MBC database including patients who initiated treatment for MBC between 2008 and 2016. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Descriptive statistics and multivariate Cox model were used. RESULTS: Of 22,266 patients, 647 (2.9%) and 929 (4.2%) patients had isolated first-site CNS metastases or combined with extra-CNS metastases, with longer OS for the group with isolated CNS metastases (16.9 versus 13.9 months, adjusted HR = 1.69 (95% CI: 1.50-1.91), p < 0.001). Among the 541 (2.4%) patients with isolated CNS metastases and no intrathecal therapy (excluding leptomeningeal metastases), HER2+ cases were preponderant over TN or HR+ /HER2- cases (41.6% versus 26.1% versus 28.5%, respectively, p < 0.01). The treatment strategy consisted of a combination of local treatment and systemic therapy (49.2%), local treatment only (35.5%) or systemic therapy only (11.4%), or symptomatic therapy only (3.9%). Median PFS was 6.1 months (95% CI: 5.7-6.8). Median OS was 20.7 months (95% CI: 17.3-24.3), reaching 37.9 months (95% CI: 25.9-47.6) in the HR+ /HER2+ subgroup. Older age, TN subtype, MBC-free interval of 6-12 months, lower performance status, and WBRT were associated with poorer survival. Patients who received systemic therapy within 3 months from MBC diagnosis had longer OS (24.1 versus 16.1 months, p = 0.031), but this was not significant on multivariate analysis [HR = 1.0 (95% CI: 0.7-1.3), p = 0.806]. CONCLUSIONS: Patients with isolated CNS metastases at MBC diagnosis represent a distinct population for which the role of systemic therapy needs to be further investigated in prospective studies.

Efficacy of trastuzumab emtansine (T-DM1) and lapatinib after dual HER2 inhibition with trastuzumab and pertuzumab in patient with metastatic breast cancer: Retrospective data from a French multicenter real-life cohort.

PURPOSE: Trastuzumab-emtansine (T-DM1), as well as lapatinib plus capecitabine were proven effective in two Phase III studies, following first-line trastuzumab plus a taxane. The introduction of dual HER2 blockade by trastuzumab and pertuzumab as first-line has positioned T-DM1 into second-line, and lapatinib plus capecitabine beyond, without formal evaluation of these strategies. METHODS: ESME Data Platform (NCT03275311) included individual data from all patients aged ≥18 years, in whom first-line treatment for metastatic breast cancer (MBC) was initiated between January 1, 2008 and December 31, 2016 in one of the 18 French Comprehensive Cancer Centers. The efficacy of T-DM1 and lapatinib plus capecitabine combination, following double blockade associating trastuzumab and pertuzumab were evaluated in this national real-life database. Eligibility criteria were: female, MBC, HER2+ tumor, first-line taxane-based chemotherapy and dual HER2-blockage by trastuzumab plus pertuzumab. Cohort A received second-line T-DM1, and Cohort B second-line T-DM1 and third or fourth-line lapatinib plus capecitabine. RESULTS: Cohort A comprised 233 patients, and Cohort B 47 patients. Median progression-free survival (PFS) was 7.1 months in Cohort A and 4.6 months in Cohort B. Median overall survival were 36.7 months and 12.9 months, respectively. PFS was significantly dependent on the preceding treatment line's duration. In cohort A, HER2 expression status was a significant predictive factor of PFS. CONCLUSION: First-line trastuzumab plus pertuzumab do not markedly diminish T-DM1's efficacy in second-line. Similarly, sequential treatment with trastuzumab plus pertuzumab then T-DM1 does not noticeably modify the efficacy of lapatinib plus capecitabine.

Impact of lobular versus ductal histology on overall survival in metastatic breast cancer: a French retrospective multicentre cohort study.

BACKGROUND: The impact of the histological lobular subtype on overall survival (OS) in metastatic breast cancer (MBC) is still under debate, with very few data available. PATIENTS AND METHODS: Using the French national multicentre Epidemiological Strategy and Medico Economics [ESME]) data platform, the primary objective was to compare the OS of patients with invasive lobular carcinoma (ILC) versus invasive ductal carcinoma (IDC) MBC, with adjustment on the main prognostic factors using two approaches: multivariable analysis and matching with a propensity score. Secondary objectives were to compare first-line progression-free survival (PFS1) and describe patients and tumour characteristics. RESULTS: Of the 16,703 patients with MBC in the ESME database, 13,111 met all inclusion criteria for the present analysis. One-thousand eight-hundred and four (13.8%) patients had ILC and 11.307 (86.2%) IDC. In the multivariable analysis, patients with ILC had a worse OS [hazard ratio (HR): 1.31; 95%CI 1.20-1.42; p < 0.0001] and a worse PFS1 (HR: 1.15; 95%CI 1.07-1.22; p < 0.0001) as compared with those with IDC, independently of hormone receptor and HER2 status. Interestingly, OS was better (HR 0.79; 95% confidence interval [CI] 0.64-0.98; p = 0.0302), worse (HR: 1.17; 95%CI 1.08-1.27; p = 0.0001) or similar (HR: 0.88; 95%CI 0.67-1.15; p = 0.3455) in patients with ILC with triple-negative, hormone receptor-positive/HER2-negative and HER2-positive MBC, respectively, compared with patients with IDC. CONCLUSION: Lobular histology is an independent adverse prognostic factor among women with MBC. ILC MBC could be considered a specific entity. Dedicated prospective studies are needed to tailor the management of these patients.

Real-life prognosis of 5041 bone-only metastatic breast cancer patients in the multicenter national observational ESME program.

BACKGROUND: Bone-only (BO) metastatic breast cancer (MBC) is considered a more favorable entity than other MBC presentations. However, only few retrospective series and data from selected randomized controlled trials have been reported so far. METHODS: Using the French national multicenter ESME (Epidemiological Strategy and Medico Economics) Data Platform, the primary objective of our study was to compare the overall survival (OS) of patients with BO versus non-BO MBC at diagnosis, with adjustment on main prognostic factors using a propensity score. Secondary objectives were to compare first-line progression-free survival (PFS1), describe treatment patterns, and estimate factors associated with OS. RESULTS: Out of 20,095 eligible women, 5041 (22.4%) patients had BO disease [hormone-receptor positive (HR+)/human epidermal growth-factor-receptor-2 negative (HER2-), n = 4 102/13,229 (31%); HER2+, n = 644/3909 (16.5%); HR-/HER2-, n = 295/2 957 (10%)]. BO MBC patients had a better adjusted OS compared with non-BO MBC [52.1 months (95% confidence interval (CI) 50.3-54.1) versus 34.7 months (95% CI 34.0-35.6) respectively]. The 5-year OS rate of BO MBC patients was 43.4% (95% CI 41.7-45.2). They also had a better PFS1 [13.1 months (95% CI 12.6-13.8) versus 8.5 months (95% CI 8.3-8.7), respectively]. This observation could be repeated in all subtypes. BO disease was an independent prognostic factor of OS [hazard ratio 0.68 (95% CI 0.65-0.72), p < 0.0001]. Results were concordant in all analyses. CONCLUSION: BO MBC patients have better outcomes compared with non-BO MBC, consistently, through all MBC subtypes.

Different effects of pioglitazone and rosiglitazone on lipid metabolism in mouse cultured liver explants.

BACKGROUND: Pioglitazone (PIO) and rosiglitazone (ROSI) are widely used as oral antidiabetic agents for treatment of type 2 diabetes. Although these medications exert similar effects on blood glucose, recent clinical studies indicated that PIO has a more pronounced beneficial effect on lipid parameters than ROSI. In order to get further insight into the lipid effects of both drugs, we tested whether PIO, compared to ROSI, could exert direct effects on lipid liver metabolism in relation with plasma lipids. METHODS: We performed in vitro studies using mice liver slices incubated 21 h either with ROSI (1 micromol/L) or PIO (7.5 micromol/L). RESULTS: We showed that both glitazones slightly reduced HMG-CoA reductase mRNA levels at the same degree but only PIO reduced intracellular cholesterol content, suggesting an alteration of cholesterol uptake rather than an inhibition of cholesterol biosynthesis. This concept was supported by the reduction of scavenger receptor class B type I expression, hepatic lipase activity and high-density lipoprotein cholesterol uptake in PIO-treated liver explants. Conversely, hepatic lipase mRNA levels were increased 3.5-fold. ROSI, but not PIO, induced acetyl-CoA carboxylase and fatty acid synthase gene expression and increased apoB secretion suggesting a stimulation of lipogenesis. Concurrently, peroxisome proliferator-activated receptor-gamma mRNA levels were induced by ROSI and not significantly changed by PIO. Besides, PIO appeared to be a more potent activator of AMP-Activated Protein Kinase than ROSI. CONCLUSIONS: PIO and ROSI exert specific direct effects on liver and extrapolating these data to humans could explain the significant improvements in plasma lipids observed in diabetic patients treated with PIO.

Palliative care delivery according to age in 12,000 women with metastatic breast cancer: Analysis in the multicentre ESME-MBC cohort 2008-2016.

INTRODUCTION: Patients with metastatic breast cancer (MBC) often require inpatient palliative care (IPC). However, mounting evidence suggests age-related disparities in palliative care delivery. This study aimed to assess the cumulative incidence function (CIF) of IPC delivery, as well as the influence of age. METHODS: The national ESME (Epidemio-Strategy-Medical-Economical)-MBC cohort includes consecutive MBC patients treated in 18 French Comprehensive Cancer Centres. ICD-10 palliative care coding was used for IPC identification. RESULTS: Our analysis included 12,375 patients, 5093 (41.2%) of whom were aged 65 or over. The median follow-up was 41.5 months (95% confidence interval [CI], 40.5-42.5). The CIF of IPC was 10.3% (95% CI, 10.2-10.4) and 24.8% (95% CI, 24.7-24.8) at 2 and 8 years, respectively. At 2 years, among triple-negative patients, young patients (<65 yo) had a higher CIF of IPC than older patients after adjusting for cancer characteristics, centre and period (65+/<65: ß = -0.05; 95% CI, -0.08 to -0.01). Among other tumour sub-types, older patients received short-term IPC more frequently than young patients (65+/<65: ß = 0.02; 95% CI, 0.01 to 0.03). At 8 years, outside large centres, IPC was delivered less frequently to older patients adjusted to cancer characteristics and period (65+/<65: ß = -0.03; 95% CI, -0.06 to -0.01). CONCLUSION: We found a relatively low CIF of IPC and that age influenced IPC delivery. Young triple-negative and older non-triple-negative patients needed more short-term IPCs. Older patients diagnosed outside large centres received less long-term IPC. These findings highlight the need for a wider implementation of IPC facilities and for more age-specific interventions.

Is the taste of fat regulated?

Over the last decade, converging data have been accumulated both in rodents and humans, supporting the existence of a sixth taste modality devoted to the perception of dietary lipids. It is well known that the sense of taste is determinant for the food choice and that the overconsumption of highly palatable energy-dense foods contributes to the current obesity epidemic. Thus, an important issue in terms of Public Health is to understand the mechanisms by which the oro-sensory perception of fat is regulated. An overview of our current knowledge in this field of investigations is proposed in this mini-review.

Obesity interferes with the orosensory detection of long-chain fatty acids in humans.

BACKGROUND: The association between the orosensory detection of lipids, preference for fatty foods, and body mass index (BMI; in kg/m(2)) is controversial in humans. OBJECTIVE: We explored the oral lipid-sensing system and the orosensory-induced autonomic reflex system in lean and obese subjects. DESIGN: Lean (BMI: 19 to <25; n = 30) and obese (BMI >30; n = 29) age-matched men were enrolled. Their oral threshold sensitivity to linoleic acid (LA) was determined by using a 3-alternative forced-choice ascending procedure, and their eating habits were established by the analysis of 4 consecutive 24-h food-consumption diaries. The effect of brief oral lipid stimulations on plasma triglyceride [(TG)pl] concentrations was analyzed in overnight-fasted lean and obese individuals subjected to a whole-mouth stimulation (sip-and-spit procedure) with a control or 1% LA emulsions for 5 min according to a within-subject randomized design. RESULTS: A large distribution of LA detection was shown in both groups. Mean detection thresholds were 0.053% (wt:wt) and 0.071% (wt:wt) in lean and obese subjects, respectively. No relation between the LA detection threshold and BMI was observed. The 5 subjects who detected only the higher concentration of LA (5% wt:wt) or were unable to distinguish properly between control and LA emulsions were obese. An analysis of dietary habits showed that these obese LA nontasters consumed more lipids and energy than did all other subjects. Brief whole-mouth stimulations (sip-and-spit procedure) with a control or 1% LA emulsion revealed an LA-mediated rise in (TG)pl concentrations in overnight-fasted, lean subjects. The origin of this change seemed to be hepatic. This (TG)pl upregulation was not shown in obese subjects, which suggested that obesity led to disturbances in the oral-brainstem-periphery loop. CONCLUSION: Altogether, these data strongly suggest that obesity may interfere with the orosensory system responsible for the detection of free long-chain fatty acids in humans. This trial was registered at clinicaltrials.gov as NCT02028975.

CD36 as a lipid sensor.

CD36 is a multifunctional protein homologous to the class B scavenger receptor SR-B1 mainly found in tissues with a sustained lipid metabolism and in several hematopoieic cells. CD36 is thought to be involved in various physiological and pathological processes like angiogenesis, thrombosis, atherogenesis, Alzheimer's disease or malaria. An additive emerging function for CD36 is a role as a lipid sensor. Location of CD36 and orthologue molecules in plasma membrane of cells in contact with the external environment (e.g. gustatory, intestinal or olfactory epithelia) allows the binding of exogenous-derived ligands including dietary lipids, diglycerides from bacterial wall in mammals and even a lipid-like pheromone in insects. Similar function might also exist in the brain in which a CD36-dependent sensing of fatty acids has been reported in ventromedial hypothalamic neurons in rodents. Specific recognition of lipid-related molecules by a receptor-like protein highly conserved throughout the evolution strongly suggests that lipid-sensing by CD36 is responsible for basic physiological functions in relation with behavior, energy balance and innate immunity.

The lipid-sensor candidates CD36 and GPR120 are differentially regulated by dietary lipids in mouse taste buds: impact on spontaneous fat preference.

BACKGROUND: Recent studies in rodents and humans suggest that the chemoreception of long-chain fatty acids (LCFA) in oral cavity is involved in the spontaneous preference for fatty foods and might contribute to the obesity risk. CD36 and GPR120 are LCFA receptors identified in rodent taste bud cells. The fact that CD36 or GPR120 gene inactivation leads to a decrease in the preference for lipids raises the question of the respective role(s) played by these gustatory lipid-sensor candidates. METHODOLOGY/PRINCIPAL FINDINGS: Using a combination of biochemical, nutritional and behavioural studies in wild-type, CD36(+/-)and CD36(-/-) mice, it was found that: 1°) CD36 and GPR120 display different diurnal rhythms in the gustatory circumvallate papillae, CD36 mRNA levels being down-regulated during the dark period in contrast to GPR120, 2°) this change is due to food intake and strictly dependent of the presence of lipids in the diet, 3°) CD36 protein levels are also rapidly but transiently decreased by the food intake, a two-fold drop in CD36 protein levels being found 1 h after refeeding, followed by a progressive return to the pre-prandial values, 4°) this down-regulation, which has a post-transcriptional origin, seems sufficient to alter the spontaneous fat preference, independently to change in the GPR120 gene expression. CONCLUSIONS/SIGNIFICANCE: In contrast to GPR120, CD36 appears to be a food-sensitive lipid sensor in the gustatory circumvallate papillae. Lipid-mediated change in lingual CD36 expression might modulate the motivation for fat during a meal, initially high and then gradually decreasing secondary to the food intake. This short-term lipid-mediated effect is reminiscent of sensory-specific satiety. These findings, which highlight the role played by CD36 in the oro-sensory perception of dietary lipids, raise the possibility of novel pharmacological strategies to modify attraction for fatty foods and decrease obesity risks.