Clinicopathological prognostic features have limited value to identify with precision newly diagnosed patients with hormone receptor (HR)-positive, HER2-negative breast cancer (BC), who would benefit from chemotherapy (CT) in addition to adjuvant hormonal therapy (HT). The 21-gene Oncotype DX Breast Recurrence Score® (RS) assay has been demonstrated to predict CT benefit, hence supporting personalized decisions on adjuvant CT. The multicenter, prospective, observational study PONDx investigated the real-life use of RS® results in Italy and its impact on treatment decisions. Physicians’ treatment recommendations (HT ± CT) were documented before and after availability of RS results, and changes in recommendations were determined. In the HR+ HER2− early BC population studied (N = 1738), physicians recommended CT + HT in 49% of patients pre-RS. RS-guided treatment decisions resulted in 36% reduction of CT recommendations. PONDx confirms that RS results provide clinically relevant information for CT recommendation in early-stage BC, resulting in a reduction of more than a third of CT use.
The addition of bevacizumab to standard chemotherapy has improved progression-free survival (PFS) and overall survival (OS) in patients with metastatic colorectal cancer (mCRC) in both first- and second line treatment, but the role of maintenance bevacizumab remains controversial. The association of various clinical factor and survival was examined in this retrospective cohort analysis. The clinical data from 220 previously untreated patients with mCRC, not progressive at the end of standard chemotherapy plus bevacizumab, were collected and analyzed. Patients were classified into two subgroups: those given with maintenance bevacizumab: "maintenance bevacizumab cohort (n = 118; MB)", and those discontinuing bevacizumab as a result of physician's or patient's decision: "no maintenance bevacizumab cohort (n = 102; noMB)". The baseline factors were well balanced between the study subgroups. Median PFS and OS for the general population was 10 months (range 7-15) and 22.5 months (range 18-26), respectively. Median PFS was 13 and 8 months in the BM and noBM cohorts, respectively (p < 0.0001). In the multivariate analysis, maintenance therapy resulted independently associated with improved PFS (HR 1.73; p < 0.001), but only objective response (OR) after first-line chemotherapy was associated with improved OS. Maintenance chemotherapy cannot be considered a standard of care after induction chemotherapy for mCRC, because the optimal balance between efficacy and safety of maintenance therapy remains a significant challenge. The results of our retrospective study suggest that maintenance therapy with bevacizumab is a safe and valuable option, particularly in those patients achieving an objective response after first-line chemotherapy.
Chronic stress can increase the risk of developing a substance use disorder in vulnerable individuals. Numerous models have been developed to probe the underlying neurobiological mechanisms, however, most prior work has been restricted to male rodents, conducted only in rats, or introduces physical injury that can complicate opioid studies. Here we sought to establish how chronic psychosocial stress influences fentanyl consumption in male and female C57BL/6 mice. We used chronic social defeat stress (CSDS), or the modified vicarious chronic witness defeat stress (CWDS), and used social interaction to stratify mice as stress-susceptible or resilient. We then subjected mice to a 15 days fentanyl drinking paradigm in the home cage that consisted of alternating forced and choice periods with increasing fentanyl concentrations. Male mice susceptible to either CWDS or CSDS consumed more fentanyl relative to unstressed mice. CWDS-susceptible female mice did not differ from unstressed mice during the forced periods, but showed increased preference for fentanyl over time. We also found decreased expression of nucleus accumbens Rho GTPases in male, but not female mice following stress and fentanyl drinking. We also compare fentanyl drinking behavior in mice that had free access to plain water throughout. Our results indicate that stress-sensitized fentanyl consumption is dependent on both sex and behavioral outcomes to stress.
Brain-derived neurotrophic factor (BDNF) has a critical role in stress response including neuropsychiatric disorders that are precipitated by stress, such as major depressive disorder (MDD). BDNF acts through its full-length BDNF receptor tyrosine kinase B (TrkB) to trigger a pro-plasticity effect. In contrast, the truncated isoform of the BDNF receptor (TrkB.t1) triggers an anti-plasticity effect. In stress outcomes, BDNF acting in the hippocampus has a stress resilience effect, and, inversely, in the nucleus accumbens (NAc), BDNF acts as a stress susceptible molecule. It is unknown if BDNF-TrkB acts on a specific NAc projection neuron, i.e., medium spiny neuron (MSN or spiny projection neuron), a subtype in stress outcomes. To determine this, we performed chronic social or vicarious witness defeat stress (CSDS or CWDS) in mice expressing TrkB.t1 in dopamine receptor 1 or 2 containing MSNs (D1- or D2-MSNs). Our results showed that TrkB.t1 overexpression in NAc D2-MSNs prevented the CSDS-induced social avoidance or other stress susceptible behaviors in male and female mice. We further showed that this overexpression in D2-MSNs blocked stress susceptible behavior induced by intra-NAc BDNF infusion. In contrast, our results demonstrate that overexpression of TrkB.t1 on NAc D1-MSNs facilitates the SDS susceptible behaviors. Our study provides enhanced details into the NAc cell subtype role of BDNF-TrkB signaling in stress outcomes.
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