Type 1 Nuclear Receptor Activity in Breast Cancer: Translating Preclinical Insights to the Clinic

The nuclear receptor (NR) family of transcription factors is intimately associated with the development, progression and treatment of breast cancer. They are used diagnostically and prognostically, and crosstalk between nuclear receptor pathways and growth factor signalling has been demonstrated in all major subtypes of breast cancer. The majority of breast cancers are driven by estrogen receptor α (ER), and anti-estrogenic therapies remain the backbone of treatment, leading to clinically impactful improvements in patient outcomes. This serves as a blueprint for the development of therapies targeting other nuclear receptors. More recently, pivotal findings into modulating the progesterone (PR) and androgen receptors (AR), with accompanying mechanistic insights into NR crosstalk and interactions with other proliferative pathways, have led to clinical trials in all of the major breast cancer subtypes. A growing body of evidence now supports targeting other Type 1 nuclear receptors such as the glucocorticoid receptor (GR), as well as Type 2 NRs such as the vitamin D receptor (VDR). Here, we reviewed the existing preclinical insights into nuclear receptor activity in breast cancer, with a focus on Type 1 NRs. We also discussed the potential to translate these findings into improving patient outcomes.

An Exploratory Pilot Study of Changes in Global DNA Methylation in Patients Undergoing Major Breast Surgery Under Opioid-Based General Anesthesia

This study aimed to investigate DNA methylation levels in patients undergoing major breast surgery under opioid-based general anesthesia. Blood samples were collected from eleven enrolled patients, before, during and after anesthesia. PBMC were isolated and global DNA methylation levels as well as DNA methyltransferase (DNMT) and cytokine gene expression were assessed. DNA methylation levels significantly declined by 26%, reversing the direction after the end of surgery. Likewise, DNMT1a mRNA expression was significantly reduced at all time points, with lowest level of −68%. DNMT3a and DNMT3b decreased by 65 and 71%, respectively. Inflammatory cytokines IL6 and TNFα mRNA levels showed a trend for increased expression at early time-points to end with a significant decrease at 48 h after surgery. This exploratory study revealed for the first time intraoperative global DNA hypomethylation in patients undergoing major breast surgery under general anesthesia with fentanyl. The alterations of global DNA methylation here observed seem to be in agreement with DNMTs gene expression changes. Furthermore, based on perioperative variations of IL6 and TNFα gene expression, we hypothesize that DNA hypomethylation may occur as a response to surgical stress rather than to opiate exposure.

SHORT TERM OUTCOMES OF A COMPARATIVE ANALYSIS BETWEEN LOCAL ANESTHETIC WOUND INFILTRATION AND REGIONAL ANESTHESIA IN BREAST SURGERY: SHOULD WE OPT FOR A SELECTIVE APPROACH?

Background: Full short-term effects of regional anesthesia in breast surgery is not well known. We aimed to assess any differences in the short-term outcomes of regional block and local anesthetic (LA) wound inltration in breast surgery. Materials and methods: A prospective non-randomized observational study of elective breast surgical procedures between 01/06/2018 and 28/02/3019 was performed at a district general hospital in the North-West England. Data comprised of patientand procedure-specic demographics, relevant health conditions, pain scale, blood pressure, analgesia requirement, Postoperative Nausea and Vomiting (PONV) score and Length of stay (LoS). Operations were classed as minor/ moderate and major. Regional anesthesia (RA) comprised of paravertebral, intercostal, pectoral and serratus blocks. Results: A total of 143 events (regional anesthesia, n=58; LA wound inltration, n=85) were analysed. Reduced pain score and longer anesthetic time were noted in the regional anesthesia group (p<0.001). A trend of reduced strong opioid requirement was also noted in the major procedure group receiving regional anesthesia. PONV scale was higher in the major surgery groups, signicantly so in the LA group (p<0.001). No signicant association was noted with various past medical histories, and LoS. A signicant increase in occurrence of wound-site haematoma (5.6%) along with per-operative hypotension was noted in the paravertebral block group. Levo-Bupivacaine was associated with least overall opioid requirement (p=0.01). Conclusions: A selective approach to provide regional anesthesia using Levo-Bupivacaine in major breast cases, irrespective of common health conditions, would likely to result in reduced pain score and opioid requirements, and offset the longer anesthetic time. Association between haematoma formation and paravertebral block merits further larger study. Plain Language Summary Ÿ Regional anesthesia in breast surgery warrants specialist skill, extra time and has potential side effects as well as benets. Ÿ Short term benets of regional anesthesia in breast surgery were assessed in this non-randomized study in comparison to traditional local anesthetic wound inltration. Ÿ Most benets, in terms of improved pain score and reduced morphine requirements, were noted in association with regional anesthesia using Levo-Bupivacaine in major breast cases. This would allow a selective approach whilst planning for most effective anesthetic and analgesic effect in breast surgery. Ÿ Higher occurrence of post-operative wound haematoma was noted mostly in association with paravertebral block, the particular type of regional anesthesia where drop of blood pressure was also signicant. Further study would help clarify the signicance of these ndings.

Studying the Effects of Collagenase (Type 1) on the Collagen in Woody Breast Meat

Abnormal collagen infiltration in the Pectoralis major, breast muscle, of fast-growing big broilers has led to woody breast (WB) myopathy resulting in meat quality issues. Mechanisms to degrade the collagen were investigated to potentially improve WB texture. Freshly deboned WB fillets (n = 5 per trial; 3 trials) were ground and divided in to 25 g portions. Aqueous collagenase Type I solution (1 mL) from concentrations of 2.5, 5, and 10 mg/mL were incorporated in ground WB samples (n = 3 samples/treatment × 3 trials). Ground WB with 1 mL water acted as a control. All the samples were placed at 4 °C for 24 h and frozen at −80 °C. Control samples without any treatment or water addition (n = 3/trial) were frozen immediately upon grinding. Data collected on total (TC), soluble (SC), and insoluble collagen (IC) content was analyzed using one-way ANOVA with Tukey’s honestly significant difference (HSD) (p ≤ 0.05). Fresh WB fillets had TC, SC, and IC content of 19.5, 4.9, and 14.6 mg/g, respectively. The addition of collagenase decreased (p ≤ 0.05) the IC to 5.8 mg/g in the 10 mg/mL treatment after 24 h. Converting IC to SC using collagenase can potentially help the poultry industry to reduce WB toughness.

Single cell transcriptomic heterogeneity in invasive ductal and lobular breast cancer cells

Invasive lobular breast carcinoma (ILC), one of the major breast cancer histological subtypes, exhibits unique clinical and molecular features compared to the other well-studied ductal cancer subtype (IDC). The pathognomonic feature of ILC is loss of E-cadherin, mainly caused by inactivating mutations within the CDH1 gene, but the extent of contribution of this genetic alteration to ILC-specific molecular characteristics remains largely understudied. To profile these features transcriptionally, we conducted single cell RNA sequencing on a panel of IDC and ILC cell lines, as well as an IDC cell line (T47D) with CRISPR-Cas9-mediated knock out (KO) of CDH1. Inspection of intra-cell line heterogeneity illustrated genetically and transcriptionally distinct subpopulations in multiple cell lines and highlighted rare populations of MCF7 cells highly expressing an apoptosis-related signature, positively correlated with a pre-adaptation signature to estrogen deprivation. Investigation of CDH1 KO-induced alterations showed transcriptomic membranous systems remodeling, elevated resemblance to ILCs in regulon activation, and suggests IRF1 as a potential mediator of reduced proliferation and increased cytokine-mediated immune-reactivity in ILCs.

Batwing mammoplasty: a safe oncoplastic technique for breast conservation in breast cancer patients with gigantomastia

Background Surgical management of breast cancer with gigantomastia can be challenging when planning breast conservation, as major breast reduction is required. Complex oncoplastic procedures can carry an additional surgical risk in this situation. We suggest batwing mammoplasty as a simple and safe oncoplastic procedure for those patients. Materials and methods Fourteen patients with gigantomastia diagnosed with breast cancer were included in this prospective cohort study. All underwent batwing mammoplasty and contralateral symmetrisation procedure between May 2016 and June 2018. Patient satisfaction assessed by the Breast-Q questionnaire. Results All patients had a body mass index above 30kg/m2 with a mean of 36.7kg/m2 (range 31.6–44.9kg/m2). The mean distance from midclavicular point to nipple was 42cm (range 38–50cm). The mean operative time was 83 minutes for procedures done by a single surgeon. Mean specimen weight was 1.2kg (ranging from 1.035–1.63kg). Postoperative complications occurred in 14.2% of patients. Nipple–areola complex viability was not compromised nor sensation impaired. The mean Breast-Q score for patient satisfaction with breasts was 68.6 (range 61–74). The mean score for physiological wellbeing was 77.3 (range 64–84) and the mean score for physical wellbeing was 35 (range 31–40). Conclusion Batwing mammoplasty is a safe and simple oncoplastic procedure in patients who have breast cancer with gigantomastia. It has short operative time and low complications rate. In our cohort of patients, there was no delay in the delivery of adjuvant treatment. The cosmetic outcome was favourable with a high patient satisfaction.