Ribociclib plus Endocrine Therapy in Early Breast Cancer.

BACKGROUND: Ribociclib has been shown to have a significant overall survival benefit in patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether this benefit in advanced breast cancer extends to early breast cancer is unclear. METHODS: In this international, open-label, randomized, phase 3 trial, we randomly assigned patients with HR-positive, HER2-negative early breast cancer in a 1:1 ratio to receive ribociclib (at a dose of 400 mg per day for 3 weeks, followed by 1 week off, for 3 years) plus a nonsteroidal aromatase inhibitor (NSAI; letrozole at a dose of 2.5 mg per day or anastrozole at a dose of 1 mg per day for ≥5 years) or an NSAI alone. Premenopausal women and men also received goserelin every 28 days. Eligible patients had anatomical stage II or III breast cancer. Here we report the results of a prespecified interim analysis of invasive disease-free survival, the primary end point; other efficacy and safety results are also reported. Invasive disease-free survival was evaluated with the use of the Kaplan-Meier method. The statistical comparison was made with the use of a stratified log-rank test, with a protocol-specified stopping boundary of a one-sided P-value threshold of 0.0128 for superior efficacy. RESULTS: As of the data-cutoff date for this prespecified interim analysis (January 11, 2023), a total of 426 patients had had invasive disease, recurrence, or death. A significant invasive disease-free survival benefit was seen with ribociclib plus an NSAI as compared with an NSAI alone. At 3 years, invasive disease-free survival was 90.4% with ribociclib plus an NSAI and 87.1% with an NSAI alone (hazard ratio for invasive disease, recurrence, or death, 0.75; 95% confidence interval, 0.62 to 0.91; P = 0.003). Secondary end points - distant disease-free survival and recurrence-free survival - also favored ribociclib plus an NSAI. The 3-year regimen of ribociclib at a 400-mg starting dose plus an NSAI was not associated with any new safety signals. CONCLUSIONS: Ribociclib plus an NSAI significantly improved invasive disease-free survival among patients with HR-positive, HER2-negative stage II or III early breast cancer. (Funded by Novartis; NATALEE ClinicalTrials.gov number, NCT03701334.).

Overall Survival with Ribociclib plus Letrozole in Advanced Breast Cancer.

BACKGROUND: In a previous analysis of this phase 3 trial, first-line ribociclib plus letrozole resulted in significantly longer progression-free survival than letrozole alone among postmenopausal patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether overall survival would also be longer with ribociclib was not known. METHODS: Here we report the results of the protocol-specified final analysis of overall survival, a key secondary end point. Patients were randomly assigned in a 1:1 ratio to receive either ribociclib or placebo in combination with letrozole. Overall survival was assessed with the use of a stratified log-rank test and summarized with the use of Kaplan-Meier methods after 400 deaths had occurred. A hierarchical testing strategy was used for the analysis of progression-free survival and overall survival to ensure the validity of the findings. RESULTS: After a median follow-up of 6.6 years, 181 deaths had occurred among 334 patients (54.2%) in the ribociclib group and 219 among 334 (65.6%) in the placebo group. Ribociclib plus letrozole showed a significant overall survival benefit as compared with placebo plus letrozole. Median overall survival was 63.9 months (95% confidence interval [CI], 52.4 to 71.0) with ribociclib plus letrozole and 51.4 months (95% CI, 47.2 to 59.7) with placebo plus letrozole (hazard ratio for death, 0.76; 95% CI, 0.63 to 0.93; two-sided P = 0.008). No new safety signals were observed. CONCLUSIONS: First-line therapy with ribociclib plus letrozole showed a significant overall survival benefit as compared with placebo plus letrozole in patients with HR-positive, HER2-negative advanced breast cancer. Median overall survival was more than 12 months longer with ribociclib than with placebo. (Funded by Novartis; MONALEESA-2 ClinicalTrials.gov number, NCT01958021.).

Single-cell sequencing provides insights into the landscape of ovary in PCOS and alterations induced by CUMS.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder related to psychological distress. However, the mechanism underlying increased prevalence of depression in PCOS remained unclear. This study aimed to explore the unique transcriptional landscape of ovary and offered a platform to explore the mechanism of PCOS, as well as the influences caused by depression. The PCOS rat model was established by letrozole whereas PCOS rat model with depression was established by letrozole combined with chronic unpredicted mild stress (CUMS). Then single-cell RNA sequencing (scRNA-Seq) was applied to analyze the transcriptional features of rat ovaries. Granulosa cells (GCs) and fibroblasts (Fibros) accounted for the top two clusters of total 12 cell types. There were nine clusters in GCs, related to inflammatory response, endoplasmic reticulum (ER) stress, and steroidogenesis. The expression of differentially expressed genes (DEG) Hes1 was higher in PCOS and PCOS + CUMS groups, exhibiting enhanced expression by pseudotime and positively related to inflammation. Pseudotemporal analysis revealed that inflammation contributed to the different GCs distributions. Moreover, analysis of DEGs and gene ontology (GO) function enrichment revealed CUMS aggravated inflammation in PCOS GCs possibly via interferon signaling pathway. In theca cells (TCs), nine clusters were observed and some of them were relevant to inflammation, ER stress, and lipid metabolism. DEGs Ass1, Insl3, and Ifi27 were positively related to Cyp17a1, and Ces1d might contribute to the different trajectory of TCs. Subsequent scRNA-seq revealed a signature profile of endothelial cells (ECs) and Fibros, which suggest that inflammation-induced damage of ECs and Fibro, further exacerbated by CUMS. Finally, analysis of T cells and mononuclear phagocytes (MPs) revealed the existence of immune dysfunction, among which interferon signaling played a critical role. These findings provided more knowledge for a better understanding PCOS from the view of inflammation and identified new biomarkers and targets for the treatment of PCOS with psychological diseases.NEW & NOTEWORTHY In this study, we mapped the landscape of polycystic ovary syndrome (PCOS) ovary with rat model induced by letrozole and provided a novel insight into the molecular mechanism of PCOS accompanied by chronic unpredicted mild stress (CUMS) at single-cell transcriptomic level. These observations highlight the importance of inflammation in the pathogenesis of PCOS, which might also be the bridge between PCOS and psychological diseases.

Ameliorative effect of sesame oil on experimentally induced polycystic ovary syndrome: A cross-link between XBP-1/PPAR-1, regulatory proteins for lipogenesis/steroids.

Polycystic ovary syndrome (PCOS) is a mixed endocrine/metabolic/reproductive disorder in women of reproductive age. Sesame oil (SO) contains sesame lignans & vitamin E with broad-spectrum antioxidant and anti-inflammatory effects. This study investigates the ameliorative effect of SO on experimentally induced PCOS and elucidates the possible molecular mechanisms with a deeper focus on the different signaling pathways involved. The study was carried out on 28 nonpregnant female Wister albino rats that were divided into four equal groups; Group I (control group) received oral 0.5% wt/vol carboxymethyl cellulose daily. Group II (SO group): orally administered SO (2 mL/kg body wt./day) for 21 days. Group III (PCOS group) received letrozole daily, 1 mg/kg, for 21 days. Group IV (PCOS + SO group): concomitantly administered letrozole and SO for 21 days. The serum hormonal and metabolic panel and the homogenate ATF-1, StAR, MAPK, PKA, and PI3K levels of the ovarian tissue were calorimetrically evaluated. However, endoplasmic reticulum (ER) stress was evaluated by ovarian XBP1 and PPAR-γ messenger RNA expression level using the qRT-PCR technique. Ovarian COX-2 was detected immunohistochemically. The results suggest that SO-treated PCOS rats showed a significantly improved hormonal, metabolic panel, inflammatory, and ER stress status with concomitant decreases in ATF-1, StAR, MAPK, PKA, and PI3K in ovarian rats compared to the correspondent values in PCOS without treatment. CONCLUSIONS: The protective effects of SO against PCOS are triggered by ameliorating regulatory proteins of ER stress, lipogenesis, and steroidogenesis through the PI3K/PKA and MAPK/ERK2 signaling cascades. SIGNIFICANCE STATEMENT: Polycystic ovary syndrome (PCOS) is the most common mixed endocrine-metabolic dysfunction among women within the reproductive period, with an estimated prevalence of 5%-26% worldwide. Doctors traditionally recommend metformin for PCOS patients. However, metformin is known to be associated with significant adverse effects and contraindications. This work aimed at shedding light on the ameliorative effect of sesame oil (SO), natural polyunsaturated fatty acids-rich oil, on the induced PCOS model. SO proved to have a marvelous effect on the metabolic and endocrine derangements in the PCOS rat model. We hoped to provide a valuable alternative treatment for PCOS patients to avoid the side effects of metformin and to help PCOS patients for whom metformin is contraindicated.

Naringenin improves ovarian health by reducing the serum androgen and eliminating follicular cysts in letrozole-induced polycystic ovary syndrome in the Sprague Dawley rats.

Polycystic ovary syndrome (PCOS) is most common in women of reproductive age, giving rise to androgen excess and anovulation, leading to infertility and non-reproductive complications. We explored the ameliorating effect of naringenin in PCOS using the Sprague Dawley (SD) rat model and human granulosa cells. Letrozole-induced PCOS rats were given either naringenin (50 mg/kg/day) alone or in combination with metformin (300 mg/kg/day), followed by the estrous cycle, hormonal analysis, and glucose sensitivity test. To evaluate the effect of naringenin on granulosa cell (hGC) steroidogenesis, we treated cells with naringenin (2.5 µM) alone or in combination with metformin (1 mM) in the presence of forskolin (10 µM). To determine the steroidogenesis of CYP-17A1, -19A1, and 3ßHSD2, the protein expression levels were examined. Treatment with naringenin in the PCOS animal groups increased ovulation potential and decreased cystic follicles and levels of androgens. The expression levels of CYP-17A1, -19A1, and 3ßHSD2, were seen restored in the ovary of PCOS SD rats' model and in the human ovarian cells in response to the naringenin. We found an increased expression level of phosphorylated-AKT in the ovary and hGCs by naringenin. Naringenin improves ovulation and suppress androgens and cystic follicles, involving AKT activation.

Low-dose spironolactone ameliorates adipose tissue inflammation and apoptosis in letrozole-induced PCOS rat model.

BACKGROUND OF STUDY: Globally, many reproductive aged women are affected by polycystic ovarian syndrome (PCOS), which is a common endocrine and metabolic disorder that is linked with adipose dysfunction and chronic low-grade inflammation. Spironolactone (SPL), a mineralocorticoid receptor blocker has been documented as a metabolic modulator. However, its immunomodulatory effect in PCOS is unknown. Therefore, the present study hypothesized that SPL would ameliorate adipose dysfunction and inflammation in experimental PCOS animals. MATERIALS AND METHODS: Female Wistar rats that were 8 weeks old were allocated into three groups. Group 1 received vehicle (distilled water; p.o.), group 2 received letrozole (1 mg/kg; p.o.) and group 3 received letrozole plus SPL (0.25 mg/kg, p.o.). The administration was performed once daily for 21 days. RESULTS: The experimental PCOS animals showed insulin resistance, hyperinsulinemia and hyperandrogenism as well as oxidative stress and elevated inflammatory biomarkers (NF-kB/TNF-/IL-6) as well as a significant decrease in triglycerides, total cholesterol, free fatty acids, GSH and G6PD in the adipose tissue of PCOS animals. In addition, immunohistochemical assessment of adipose tissue showed significant expression of BAX and inflammasome, indicating apoptosis and inflammation compared to control animals. Nevertheless, administration of SPL attenuated these perturbations. CONCLUSION: Altogether, the present study suggests that low-dose spironolactone confers protection against adipose dysfunction in experimental PCOS animals by attenuating inflammation, oxidative stress and cellular apoptosis.

Genome-wide association study of aromatase inhibitor discontinuation due to musculoskeletal symptoms.

OBJECTIVE: Aromatase inhibitors (AIs) are commonly used to treat hormone receptor positive (HR +) breast cancer. AI-induced musculoskeletal syndrome (AIMSS) is a common toxicity that causes AI treatment discontinuation. The objective of this genome-wide association study (GWAS) was to identify genetic variants associated with discontinuation of AI therapy due to AIMSS and attempt to replicate previously reported associations. METHODS: In the Exemestane and Letrozole Pharmacogenetics (ELPh) study, postmenopausal patients with HR + non-metastatic breast cancer were randomized to letrozole or exemestane. Genome-wide genotyping of germline DNA was conducted followed by imputation. Each imputed variant was tested for association with time-to-treatment discontinuation due to AIMSS using a Cox proportional hazards model assuming additive genetic effects and adjusting for age, baseline pain score, prior taxane treatment, and AI arm. Secondary analyses were conducted within each AI arm and analyses of candidate variants previously reported to be associated with AIMSS risk. RESULTS: Four hundred ELPh participants were included in the combined analysis. Two variants surpassed the genome-wide significance level in the primary analysis (p value < 5 × 10-8), an intronic variant (rs79048288) within CCDC148 (HR = 4.42, 95% CI: 2.67-7.33) and an intergenic variant (rs912571) upstream of PPP1R14C (HR = 0.30, 95% CI: 0.20-0.47). In the secondary analysis, rs74418677, which is known to be associated with expression of SUPT20H, was significantly associated with discontinuation of letrozole therapy due to AIMSS (HR = 5.91, 95% CI: 3.16-11.06). We were able to replicate associations for candidate variants previously reported to be associated with AIMSS in this cohort, but were not able to replicate associations for any other variants previously reported in other patient cohorts. CONCLUSIONS: Our GWAS findings identify several candidate variants that may be associated with AIMSS risk from AI generally or letrozole specifically. Validation of these associations in independent cohorts is needed before translating these findings into clinical practice to improve treatment outcomes in patients with HR + breast cancer.

Extended therapy with letrozole as adjuvant treatment of postmenopausal patients with early-stage breast cancer: a multicentre, open-label, randomised, phase 3 trial.

BACKGROUND: The benefit of extending aromatase inhibitor therapy beyond 5 years in the context of previous aromatase inhibitors remains controversial. We aimed to compare extended therapy with letrozole for 5 years versus the standard duration of 2-3 years of letrozole in postmenopausal patients with breast cancer who have already received 2-3 years of tamoxifen. METHODS: This multicentre, open-label, randomised, phase 3 trial was done at 69 hospitals in Italy. Women were eligible if they were postmenopausal at the time of study entry, had stage I-III histologically proven and operable invasive hormone receptor-positive breast cancer, had received adjuvant tamoxifen therapy for at least 2 years but no longer than 3 years and 3 months, had no signs of disease recurrence, and had an Eastern Cooperative Oncology Group performance status of 2 or lower. Patients were randomly assigned (1:1) to receive 2-3 years (control group) or 5 years (extended group) of letrozole (2·5 mg orally once a day). Randomisation, with stratification by centre, with permuted blocks of size 12, was done with a centralised, interactive, internet-based system that randomly generated the treatment allocation. Participants and investigators were not masked to treatment assignment. The primary endpoint was invasive disease-free survival in the intention-to-treat population. Safety analysis was done for patients who received at least 1 month of study treatment. This trial was registered with EudraCT, 2005-001212-44, and ClinicalTrials.gov, NCT01064635. FINDINGS: Between Aug 1, 2005, and Oct 24, 2010, 2056 patients were enrolled and randomly assigned to receive letrozole for 2-3 years (n=1030; control group) or for 5 years (n=1026; extended group). After a median follow-up of 11·7 years (IQR 9·5-13·1), disease-free survival events occurred in 262 (25·4%) of 1030 patients in the control group and 212 (20·7%) of 1026 in the extended group. 12-year disease-free survival was 62% (95% CI 57-66) in the control group and 67% (62-71) in the extended group (hazard ratio 0·78, 95% CI 0·65-0·93; p=0·0064). The most common grade 3 and 4 adverse events were arthralgia (22 [2·2%] of 983 patients in the control group vs 29 [3·0%] of 977 in the extended group) and myalgia (seven [0·7%] vs nine [0·9%]). There were three (0·3%) serious treatment-related adverse events in the control group and eight (0·8%) in the extended group. No deaths related to toxic effects were observed. INTERPRETATION: In postmenopausal patients with breast cancer who received 2-3 years of tamoxifen, extended treatment with 5 years of letrozole resulted in a significant improvement in disease-free survival compared with the standard 2-3 years of letrozole. Sequential endocrine therapy with tamoxifen for 2-3 years followed by letrozole for 5 years should be considered as one of the optimal standard endocrine treatments for postmenopausal patients with hormone receptor-positive breast cancer. FUNDING: Novartis and the Italian Ministry of Health. TRANSLATION: For the Italian translation of the abstract see Supplementary Materials section.

Abemaciclib in combination with endocrine therapy for East Asian patients with HR+, HER2- advanced breast cancer: MONARCH 2 & 3 trials.

This post hoc analysis of MONARCH 2 and MONARCH 3 assesses the efficacy, safety, and pharmacokinetics (PK) of abemaciclib in combination with endocrine therapy (ET) in East Asian patients with hormone receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer. MONARCH 2 and MONARCH 3 are global, randomized, double-blind, phase 3 studies of abemaciclib/placebo + fulvestrant and abemaciclib/placebo + nonsteroidal aromatase inhibitor (NSAI, anastrozole or letrozole), respectively. The East Asian population comprised 212 (31.7%) of the 669 intent-to-treat (ITT) population in the MONARCH 2 trial and 144 (29.2%) of the 493 ITT patients in the MONARCH 3 trial. In the East Asian population, median progression-free survival (PFS) was significantly prolonged in the abemaciclib arm compared with placebo in both MONARCH 2 (hazard ratio [HR], 0.520; 95% confidence interval [CI], 0.362 to 0.747; P < .001; median: 21.2 vs 11.6 months) and MONARCH 3 (HR, 0.326; 95% CI, 0.200 to 0.531, P < .001; median: not reached vs 12.82 months). Diarrhea (MONARCH 2: 90%; MONARCH 3: 88%) and neutropenia (MONARCH 2: 68%; MONARCH 3: 58%) were the most frequent adverse events observed in the East Asian populations. Abemaciclib exposures and PK were similar in East Asians and the non-East Asian populations of both trials. Abemaciclib in combination with ET in the East Asian populations of MONARCH 2 and MONARCH 3 provided consistent results with the ITT populations, demonstrating improvements in efficacy with generally tolerable safety profiles for patients with HR+, HER2- advanced breast cancer.

Cumulative incidence of cardiovascular events under tamoxifen and letrozole alone and in sequence: a report from the BIG 1-98 trial.

BACKGROUND: Compared to tamoxifen, adjuvant treatment with aromatase inhibitors improves disease outcomes of postmenopausal women with hormone receptor-positive early breast cancer. In the international, randomized, double-blind BIG 1-98 trial, 8010 women were randomized to receive tamoxifen, letrozole, or sequential use of the agents for 5 years. With a focus on switching between agents, we investigated cardiovascular events over the entire 5-year treatment period. METHODS: Of the 6182 patients enrolled, 6144 started trial treatment and were included in this analysis. Adverse events occurring during study treatment until 30 days after cessation were considered. Eight cardiovascular event types were defined. Cumulative incidence of events were estimated using the Kaplan-Meier method, without consideration for competing events. Multivariable Cox models estimated hazard ratios (HR) with 95% confidence intervals (CI) for pairwise comparisons of treatment arms. RESULTS: While on study treatment, 6.5% of patients (n = 397) had any cardiac events reported; for 2.4%, the event was grades 3-5, of which 11 (0.2%) were grade 5. Letrozole monotherapy was associated with higher risk of grade 1-5 ischemic heart disease (HR = 1.81; 95% CI, 1.06-3.08) compared with tamoxifen monotherapy. Patients assigned sequential tamoxifen →letrozole (HR = 1.59; 95% CI, 0.92-2.74) or sequential letrozole → tamoxifen (HR = 1.20; 95% CI, 0.68-2.14) showed a lesser degree of risk elevation. Patients assigned to tamoxifen-containing regimens had significantly higher risk of grade 1-5 thromboembolic events (tamoxifen monotherapy HR = 2.10; 95% CI, 1.42-3.12; tamoxifen → letrozole HR = 1.96; 95% CI, 1.32-2.92; letrozole → tamoxifen HR = 1.56; 95% CI 1.03-2.35) as compared with patients assigned letrozole alone. CONCLUSION: When initiating or switching between adjuvant endocrine treatments in postmenopausal patients, age and medical history, with special attention to prior cardiovascular events, should be balanced with expected benefit of the treatment.

Does the additional use of clomiphene citrate or letrozole for in vitro fertilization deserve more attention?

BACKGROUND: Adding clomiphene citrate (CC) and/or letrozole (LE) to in vitro fertilization (IVF) cycles for mild ovarian stimulation is a general approach. Although lots of researches have demonstrated partial benefits of the strategy, all-around effects of oral medications remained deficient. This paper aims to assess whether an addition of oral medication will result in considerable outcomes on T-Gn (total dose of gonadotropin), Gn days, total retrieved ova, high quality embryos, blastocyst number, ovarian hyperstimulation syndrome (OHSS) rate, clinical pregnancy rate and cumulative pregnancy rate, even if it was not conventional mild/minimal stimulations. RESULTS: Participants were categorized to three diverse populations as high responders, normal responders and poor responders according to basal antral follicle count. T-Gn in patients treated with CC/LE distinctly decreased from 2496.96 IU/d to 1827.68 IU/d, from 2860.28 IU/d to 2119.99 IU/d, and from 3182.15 IU/d to 1802.84 IU/d, respectively. For high ovary responders and normal responders, the OHSS incidence rate also declined from 29.2 to 4.3% (P < 0.001) and from 1.1 to 0.0% (P = 0.090). Other, there was no statistical difference with respect to the T-retrieved ova (total retrieved ova), high quality embryos, cultured blastocyst and blastocyst number in high responders. For normal responders and poor ovary responders, T-Gn, Gn days, T-retrieved ova, high quality embryos, cultured blastocyst and blastocysts number in oral medications group all apparently decreased. Clinical pregnancy rate per fresh cycle of poor responders with prior oral medications was significantly decreased (25.7% vs. 50.8%, P = 0.005), and no significant differences in high responders and normal responders were expressed (52.5% vs. 44.2%, P = 0.310; 51.9% vs. 42.4%, P = 0.163) between two groups of participants. The numbers of cumulative pregnancy rates were lower in the conventional group compared to the add group for high (75.90% versus 81.03%, P = 0.279), normal (62.69% versus 71.36%, P = 0.016) and poor (39.74% versus 68.21%, P < 0.001) responders. CONCLUSIONS: The addition of CC/LE to the ovulation induction during IVF has certain efficacy in terms of low cost, low OHSS incidence. CC/LE deserves more recommendations as a responsible strategy in high responders due to advantageous pregnancy outcomes. For normal responders, the strategy needs to be considered with more comprehensive factors.

Adverse Effects of Aromatase Inhibition on the Brain and Behavior in a Nonhuman Primate.

Breast cancer patients using aromatase inhibitors (AIs) as an adjuvant therapy often report side effects, including hot flashes, mood changes, and cognitive impairment. Despite long-term use in humans, little is known about the effects of continuous AI administration on the brain and cognition. We used a primate model of human cognitive aging, the common marmoset, to examine the effects of a 4-week daily administration of the AI letrozole (20 µg, p.o.) on cognition, anxiety, thermoregulation, brain estrogen content, and hippocampal pyramidal cell physiology. Letrozole treatment was administered to both male and female marmosets and reduced peripheral levels of estradiol (E2), but unexpectedly increased E2 levels in the hippocampus. Spatial working memory and intrinsic excitability of hippocampal neurons were negatively affected by the treatment possibly due to increased hippocampal E2. While no changes in hypothalamic E2 were observed, thermoregulation was disrupted by letrozole in females only, indicating some impact on hypothalamic activity. These findings suggest adverse effects of AIs on the primate brain and call for new therapies that effectively prevent breast cancer recurrence while minimizing side effects that further compromise quality of life.SIGNIFICANCE STATEMENT Aromatase inhibitors (AIs) are used as an adjuvant therapy for estrogen-receptor-positive breast cancer and are associated with side effects, including hot flashes, depression/anxiety, and memory deficits severe enough for many women to discontinue this life-saving treatment. AIs are also used by men, yet sex differences in the reported side effects have not been systematically studied. We show that AI-treated male and female marmosets exhibit behavioral changes consistent with these CNS symptoms, as well as elevated hippocampal estradiol and compromised hippocampal physiology. These findings illustrate the need for (1) a greater understanding of the precise mechanisms by which AIs impact brain function and (2) the development of new treatment approaches for breast cancer patients that minimize adverse effects on the brain.

Genetic and clinical predictors of arthralgia during letrozole or anastrozole therapy in breast cancer patients.

PURPOSE: Female patients with breast cancer frequently develop arthralgia when treated with aromatase inhibitors (AI). Although the mechanism of AI-induced arthralgia is unknown, potential biomarkers have been identified. The purpose of this study was to investigate the clinical and genetic predictors of AI-induced arthralgia in a prospective cohort of patients with estrogen receptor-positive breast cancer. METHODS: One hundred and ninety-six patients were enrolled at initiation of AI therapy with either letrozole or anastrozole. Patients completed two validated self-report questionnaires assessing pain, stiffness, and physical function at baseline, and repeated the questionnaires at two and at six months after the initiation of treatment with an AI. Germline DNA of all patients was genotyped for seven single-nucleotide polymorphisms (SNPs) previously identified by genetic screens and genome-wide association studies as associated with AI-induced arthralgia. RESULTS: More than 50% of the study group experienced arthralgia symptoms. Genetic analysis revealed that four SNPs, in CYP19A1 (rs4775936) and ESR1 (rs9322336, rs2234693, rs9340799), were associated with the development of arthralgia (adjusted P = 0.016, 0.018, 0.017, 0.047). High body mass index (BMI) was also associated with the development of arthralgia symptoms (adjusted P = 0.001). Patients prescribed letrozole were significantly more likely to develop arthralgia than patients on anastrozole (P = 0.018), and also more likely to discontinue AI therapy due to arthralgia. The CYP19A1 (rs4775936) SNP was significantly associated with discontinuation of therapy due to intolerable arthralgia. CONCLUSIONS: Our results suggested that BMI and AI drug (letrozole versus anastrozole) were clinical predictors of arthralgia, while genetic variants rs4775936, rs9322336, rs2234693, and rs9340799 were genetic predictors of AI-induced arthralgia. Significantly, rs4775936 was also a predictor of discontinuation of therapy.

Association of CYP19A1 gene variations with adjuvant letrozole-induced adverse events in South Indian postmenopausal breast cancer cohort expressing hormone-receptor positivity.

PURPOSE: Musculoskeletal adverse events (MS-AEs) and vasomotor symptoms (VMSs) are the major side-effects of newer generation non-steroidal aromatase inhibitor (AI), letrozole. Single-nucleotide polymorphisms (SNPs) in CYP19A1 gene coding for the enzyme aromatase are related to AI treatment-associated adverse drug reactions. Therefore, we aimed to determine whether SNPs in the CYP19A1 gene are associated with adjuvant letrozole-induced 'specific' AEs in postmenopausal hormone receptor-positive (HR+) breast cancer patients. METHODS: Genomic DNA was isolated from 198 HR+ breast cancer patients by the phenol-chloroform method, and eleven SNPs in the CYP19A1 gene were genotyped by TaqMan genotyping assays on the qRT-PCR system. Toxicity was assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0, and the data were analyzed using SPSS v19.0 and Haploview v4.2 statistical software. RESULTS: Subjects carrying the genetic variants of CYP19A1 gene SNP rs700519 had significantly higher odds (OR 2.33; 95% CI [1.29-4.20], P = 0.0057) of MS-AEs under dominant statistical effect. The frequency of the two distinct haplotypes that include the variant allele 'T' at rs700519 locus, H5-GCTATCTGGCG (P = 0.042) and H11-GCTATTGCACG (P = 0.013) were significantly higher in patients with musculoskeletal toxicity than in those without MS-AEs and thus predisposing to MS-AEs. Similarly, H6-GCCAGCTGGCG (P = 0.037) haplotype exhibited higher frequencies in patients presented with VMSs. However, no such association was observed between CYP19A1 genotypes and VMSs. CONCLUSIONS: To the best of our knowledge, this is the first study assessing the impact of CYP19A1 genetic variations with adjuvant letrozole treatment-associated AEs in Indian women. Genetic variations in the CYP19A1 gene is associated with letrozole-induced AEs and warrants further investigation in larger cohorts to validate this finding.

ΔKi67 proliferation index as independent predictive and prognostic factor of outcome in luminal breast cancer: data from neoadjuvant letrozole-based treatment.

A key tool for monitoring breast cancer patients under neoadjuvant treatment is the identification of reliable predictive markers. Ki67 has been identified as a prognostic and predictive marker in ER-positive breast cancer. Ninety ER-positive, HER2 negative locally advanced breast cancer patients received letrozole (2.5 mg daily) and cyclophosphamide (50 mg daily) with/without Sorafenib (400 mg/bid daily) for 6 months before undergoing surgery. Ki67 expression and tumor size measured with caliber were determined at baseline, after 30 days of treatment and at the end of treatment. Patients were assigned to a clinical response category according to Response Evaluation Criteria in Solid Tumors, both at 30 days and before surgery and further classified as high-responder and low-responder according to the median variation of Ki67 values between biopsy and 30 days and between biopsy and surgery time. The predictive role of Ki67 and its changes with regard to clinical response and survival was analyzed. No differences in terms of survival outcomes emerged between the arms of treatment, while we observed a higher percentage of women with progression or stable disease in arm with the combination containing Sorafenib (20.5% vs 7.1%, p = 0.06). Clinical complete responders experienced a greater overall variation in Ki67 when compared with partial responders and patients with progressive/stable disease (66.7% vs 30.7%, p = 0.009). High responders showed a better outcome than low responders in terms of both disease-free survival (p = 0.009) and overall survival (p = 0.002). ΔKi67 score evaluated between basal and residual tumor at definitive surgery showed to be highly predictive of clinical complete response, and a potential parameter to be used for predicting disease-free survival and overall survival in luminal breast cancer treated with neoadjuvant endocrine-based therapy.

Subacute cutaneous lupus erythematosus with positive anti-Ro antibodies following palbociclib and letrozole treatment: A case report and literature review.

Drug-induced subacute cutaneous lupus erythematosus (DI-SCLE) is an uncommon but well-described phenomenon, most often seen in association with antihypertensives and antifungal medications. In recent years, rare reports of DI-SCLE have been described in patients being treated with targeted therapies. Herein, we describe a case of DI-SCLE in association with palbociclib and letrozole treatment for metastatic breast cancer. This report is the first known case of DI-SCLE with positive anti-Ro antibodies in this setting. We also summarize the literature describing DI-SCLE in association with targeted therapies to date and its possible association with dysregulation of the vascular endothelial growth factor pathway.

Letrozole Rat Model Mimics Human Polycystic Ovarian Syndrome and Changes in Insulin Signal Pathways.

BACKGROUND The aim of this study was to explore whether letrozole and high-fat diets (HFD) can induce obese insulin-resistant polycystic ovary syndrome (PCOS) with all reproductive and metabolic phenotypes in a rat model. MATERIAL AND METHODS Twenty-four 3-week-old female Sprague-Dawley rats were randomized into 4 groups: control, Letrozole, HFD, and Letrozol+HFD. The PCOS model was induced by 12 weeks of Letrozole treatment (1 mg/kg p.o. dissolved in 0.5% CMC solutions once daily) and HFD. Ovarian morphology, estrous cyclicity, hormonal status, body weight, glucose and insulin tolerance, lipid profile, and insulin signaling pathway were investigated. RESULTS The rat model manifests anovulatory cycles and PCO morphology, increased body weight, elevated testosterone levels, abnormal glucose and lipid metabolism, and insulin resistance. The rat model also expresses significantly decreased phosphorylation of 6 essential signaling proteins - INSR, IRS, PI3K, AKT, ERK1, ERK2 - in the PI3K/AKT and MAPK/ERK pathways in the classic insulin-sensitive tissues (e.g., quadriceps femoris muscle, omentum majus, and liver), as well as non-classic target ovary tissues. Disrupted insulin signaling contributes to the decrease in insulin sensitivity and compensatory hyperinsulinemia in PCOS rats. CONCLUSIONS Continuous administration of letrozole and high-fat diets can induce PCOS, metabolic phenotypes, and disrupted activation of the insulin signaling pathway.

Necrotizing leukocytoclastic small vessel vasculitis associated with letrozole: A case report.

INTRODUCTION: Letrozole is an aromatase inhibitor that used to treat breast cancers. Letrozole-associated skin vasculitis is a rare side effect of this medication, in this study we report a case of necrotizing type of Small vessel cutaneous vasculitis associated with letrozole consumption. CASE PRESENTATION: A 45-year-old woman was referred to the dermatology clinic with painful necrotic annular lesions on the lower limbs. Her past medical history showed evidence of breast cancer and taking letrozole. Five months after the start of letrozole, the patient's signs and symptoms had appeared. Physical examination revealed annular plaques with erythematous margin and multiple necrotic centers that were painful to touch. The histopathology showed extravasated red blood cells and leukocytoclasis as well as neutrophils surrounding and infiltrating the wall of blood vessels in superficial and mid dermis. We discontinued letrozole, then prescribed topical clobetasol, systemic prednisolone, and colchicine; the lesions began to heal after 1 month from the start of treatment, and did not recur after discontinuing the treatment. DISCUSSION: Pathogenesis of vasculitis caused by aromatase inhibitors is not fully elucidated, but estrogen depletion and idiosyncratic drug reaction has been proposed. Cutaneous leukocytoclastic small vessel vasculitis (CLSVV) resulting from aromatase inhibitors is relatively rare so it is recommended to consider drug-induced CLSVV in other patients treated with aromatase inhibitors.

Neoadjuvant letrozole plus taselisib versus letrozole plus placebo in postmenopausal women with oestrogen receptor-positive, HER2-negative, early-stage breast cancer (LORELEI): a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial.

BACKGROUND: Endocrine therapy-based neoadjuvant treatment for luminal breast cancer allows efficient testing of new combinations before surgery. The activation of the phosphatidylinositol-3-kinase (PI3K) pathway is a known mechanism of resistance to endocrine therapy. Taselisib is an oral, selective PI3K inhibitor with enhanced activity against PIK3CA-mutant cancer cells. The LORELEI trial tested whether taselisib in combination with letrozole would result in an increased proportion of objective responses and pathological complete responses. METHODS: In this multicentre, randomised, double-blind, parallel-cohort, placebo-controlled phase 2, study, we enrolled postmenopausal women (aged ≥18 years) with histologically confirmed, oestrogen receptor (ER)-positive, HER2-negative, stage I-III, operable breast cancer, from 85 hospitals in 22 countries worldwide. To be eligible, patients had have an Eastern Cooperative Oncology Group (ECOG) performance status 0-1, adequate organ function, and had to have evaluable tumour tissue for PIK3CA genotyping. Patients were randomly assigned (1:1) by means of a permuted block algorithm (block size of four) via an interactive voice or web-based response system, to receive letrozole (2·5 mg/day orally, continuously) with either 4 mg of oral taselisib or placebo (on a 5 days-on, 2 days-off schedule) for 16 weeks, followed by surgery. Randomisation was stratified by tumour size and nodal status. Site staff, patients, and the sponsor were masked to treatment assignment. Coprimary endpoints were the proportion of patients who achieved an objective response by centrally assessed breast MRI and a locally assessed pathological complete response in the breast and axilla (ypT0/Tis, ypN0) at surgery in all randomly assigned patients and in patients with PIK3CA-mutant tumours. Analyses were done in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT02273973, and is closed to accrual. FINDINGS: Between Nov 12, 2014, and Aug 12, 2016, 334 participants were enrolled and randomly assigned to receive letrozole and placebo (n=168) or letrozole and taselisib (n=166). Median follow-up was 4·9 months (IQR 4·7-5·1). The study met one of its primary endpoints: the addition of taselisib to letrozole was associated with a higher proportion of patients achieving an objective response in all randomly assigned patients (66 [39%] of 168 patients in the placebo group vs 83 [50%] of 166 in the taselisib group; odds ratio [OR] 1·55, 95% CI 1·00-2·38; p=0·049) and in the PIK3CA-mutant subset (30 [38%] of 79 vs 41 [56%] of 73; OR 2·03, 95% CI 1·06-3·88; p=0·033). No significant differences were observed in pathological complete response between the two groups, either in the overall population (three [2%] of 166 in the taselisib group vs one [1%] of 168 in the placebo group; OR 3·07 [95% CI 0·32-29·85], p=0·37) or in the PIK3CA-mutant cohort (one patient [1%) vs none [0%]; OR not estimable, p=0·48). The most common grade 3-4 adverse events in the taselisib group were gastrointestinal (13 [8%] of 167 patients), infections (eight [5%]), and skin-subcutaneous tissue disorders (eight [5%]). In the placebo group, four (2%) of 167 patients had grade 3 or worse vascular disorders, two (1%) had gastrointestinal disorders, and two (1%) patients had grade 3 or worse infections and infestations. There was no grade 4 hyperglycaemia and grade 3 cases were asymptomatic. Serious adverse events were more common in the taselisib group (eight [5%] patients with infections and seven [4%] with gastrointestinal effects) than in the placebo group (one [1%] patient each with grade 3 postoperative wound and haematoma infection, grade 4 hypertensive encephalopathy, grade 3 acute cardiac failure, and grade 3 breast pain). One death occurred in the taselisib group, which was not considered to be treatment-related. INTERPRETATION: The increase in the proportion of patients who achieved an objective response from the addition of taselisib to endocrine therapy in a neoadjuvant setting is consistent with the clinical benefit observed in hormone receptor-positive, HER2-negative, metastatic breast cancer. FUNDING: Genentech and F Hoffmann-La Roche.

Use of letrozole after aromatase inhibitor-based therapy in postmenopausal breast cancer (NRG Oncology/NSABP B-42): a randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: The optimal duration of extended therapy with aromatase inhibitors in patients with postmenopausal breast cancer is unknown. In the NSABP B-42 study, we aimed to determine whether extended letrozole treatment improves disease-free survival after 5 years of aromatase inhibitor-based therapy in women with postmenopausal breast cancer. METHODS: This randomised, double-blind, placebo-controlled, phase 3 trial was done in 158 centres in the USA, Canada, and Ireland. Postmenopausal women with stage I-IIIA hormone receptor-positive breast cancer, who were disease-free after about 5 years of treatment with an aromatase inhibitor or tamoxifen followed by an aromatase inhibitor, were randomly assigned (1:1) to receive 5 years of letrozole (2·5 mg orally per day) or placebo. Randomisation was stratified by pathological node status, previous tamoxifen use, and lowest bone mineral density T score in the lumbosacral spine, total hip, or femoral neck. The primary endpoint was disease-free survival, defined as time from randomisation to breast cancer recurrence, second primary malignancy, or death, and was analysed by intention to treat. To adjust for previous interim analyses, the two-sided statistical significance level for disease-free survival was set at 0·0418. This study is registered with ClinicalTrials.gov, number NCT00382070, is active, and is no longer enrolling patients. FINDINGS: Between Sept 28, 2006, and Jan 6, 2010, 3966 patients were randomly assigned to receive letrozole (n=1983) or placebo (n=1983). Follow-up information was available for 3903 patients for the analyses of disease-free survival. Median follow-up was 6·9 years (IQR 6·1-7·5). Letrozole treatment did not significantly improve disease-free survival (339 disease-free survival events were reported in the placebo group and 292 disease-free survival events were reported in the letrozole group; hazard ratio 0·85, 95% CI 0·73-0·999; p=0·048). 7-year disease-free survival estimate was 81·3% (95% CI 79·3-83·1) in the placebo group and 84·7% (82·9-86·4) in the letrozole group. The most common grade 3 adverse events were arthralgia (47 [2%] of 1933 patients in the placebo group vs 50 [3%] of 1941 patients in the letrozole group) and back pain (44 [2%] vs 38 [2%]). The most common grade 4 adverse event in the placebo group was thromboembolic event (eight [<1%]) and the most common grade 4 adverse events in the letrozole group were urinary tract infection, hypokalaemia, and left ventricular systolic dysfunction (four [<1%] each). INTERPRETATION: After 5 years of aromatase inhibitor-based therapy, 5 years of letrozole therapy did not significantly prolong disease-free survival compared with placebo. Careful assessment of potential risks and benefits is required before recommending extended letrozole therapy to patients with early-stage breast cancer. FUNDING: National Cancer Institute, Korea Health Technology R&D Project, Novartis.