Identification of a Panel of miRNAs Associated with Resistance to Palbociclib and Endocrine Therapy.

We investigated whether we could identify a panel of miRNAs associated with response to treatment in tumor tissues of patients with Hormone Receptor-positive/HER2-negative metastatic breast cancer treated with endocrine therapy (ET) and the CDK4/6 inhibitor (CDK4/6i)i palbociclib. In total, 52 patients were evaluated, with 41 receiving treatment as the first line. The overall median PFS was 20.8 months (range 2.5-66.6). In total, 23% of patients experienced early progression (<6 months). Seven miRNAs (miR-378e, miR-1233, miR-99b-5p, miR-1260b, miR-448, -miR-1252-5p, miR-324-3p, miR-1233-3p) showed a statistically significant negative association with PFS. When we considered PFS < 6 months, miR-378e, miR-99b-5p, miR-877-5p, miR-1297, miR-455-5p, and miR-4536-5p were statistically associated with a poor outcome. In the multivariate analysis, the first three miRNAs confirmed a significant and independent impact on PFS. The literature data and bioinformatic tools provide an underlying molecular rationale for most of these miRNAs, mainly involving the PI3K/AKT/mTOR pathway and cell-cycle machinery as cyclin D1, CDKN1B, and protein p27Kip1 and autophagy. Our findings propose a novel panel of miRNAs associated with a higher likelihood of early progression in patients treated with ET and Palbociclib and may contribute to shed some light on the mechanisms of de novo resistance to CDK4/6i, but this should be considered exploratory and evaluated in larger cohorts.

Predictors of fulvestrant long-term benefit in hormone receptor-positive/HER2 negative advanced breast cancer.

We retrospectively investigated in women treated with fulvestrant for HR+/HER2 negative advanced breast cancer clinical, pathological and molecular features associated with long-term benefit from treatment defined as being progression-free at 18 months. Specifically, we analyzed on formalin-fixed paraffin-embedded tumor samples ESR1 and PI3KCA mutations and miRNAs profiles. 59 patients were evaluable (median age of 67 years, range 32-92). 18-month PFS rate was 27%; the lack of visceral metastases significantly predicted the likelihood of being progression-free at 18 months, while PI3KCA mutations, found in 36% of patients, were not associated with 18-month PFS. As of miRNAs, miR-549a, miR-644a, miR-16-5p were negatively while let-7c-5p was positively associated with 18-month PFS. In addition, miR-520d-3p and miR-548g-3p values were significantly lower while miR-603, miR-181a-5p and miR-199a-miR-199b-3p values were significantly higher in patients achieving 18-month PFS. In silico analysis of targets modulated by these two latter groups of miRNAs show that in patients achieving 18-month PFS the Hippo and Wnt signaling pathways were predicted to be upregulated while endocrine resistance was potentially repressed by miR-603, miR-181a-5p and miR-199a-miR-199b-3p. Our results provide additional clues on the molecular mechanisms involved in fulvestrant activity and resistance. Underlying pathways should be further elucidated and confirmed in larger cohorts.

Is Anti-Müllerian Hormone a Marker of Ovarian Reserve in Young Breast Cancer Patients Receiving a GnRH Analog during Chemotherapy?

Introduction: Anti-Müllerian hormone (AMH) is the most reliable biomarker of ovarian reserve; however, its role in predicting ovarian recovery after chemotherapy is unclear. Administration of a GnRH analog (GnRHa) during chemotherapy significantly reduces the ovarian failure rate and increases the pregnancy rate. The available data on the behavior of AMH during concurrent administration of chemotherapy and GnRHa are inconsistent. We investigated whether concurrent administration of triptorelin and adjuvant chemotherapy might reduce the expected drop of AMH. Methods: Eligible patients were premenopausal women aged <40 years, with a diagnosis of early breast cancer, and candidates to 4-8 cycles of adjuvant chemotherapy. Triptorelin (3.75 mg i.m.) was started before chemotherapy and administered every 4 weeks thereafter. The principal endpoint was the proportion of patients with an AMH percent change ≤50% between 12 months after chemotherapy and basal levels. The secondary endpoint was the proportion of patients achieving postchemotherapy AMH levels above the threshold of 0.2 ng/mL. Results: Fifty patients were enrolled, 31 of whom had blood samples available at baseline and 1 year after the end of chemotherapy. AMH decreased to nearly undetectable levels after chemotherapy and recovered after 12 months, but they did not exceed 1 tenth of the pretreatment levels. As for the secondary endpoint, 15 of the 31 patients recovered AMH levels above the threshold. Conclusions: This study did not reach its principal endpoint; however, the rate of 48% of patients who recovered AMH above threshold levels favorably compared with those in studies without concurrent GnRHa, supporting a better recovery of AMH with triptorelin.

Iron supplementation during treatment with erythropoiesis-stimulating agents for cancer-related anemia.

Unresponsiveness to erythropoiesis-stimulating agents is a major limitation to the treatment of chemotherapy-related anemia. This is often related to a disregulation of iron metabolism leading to functional iron deficiency. However, the use of iron supplementation during treatment with erythropoiesis-stimulating agents has not been as rigorously pursued in anemic patients with cancer as it has in chronic kidney disease. In this article, we review and discuss the role of iron supplementation in the setting of chemotherapy-related anemia in view of recently published clinical trials addressing this issue.