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Background: Treatment of estrogen receptor (ER)-positive breast cancer with selective estrogen receptor degraders (SERDs) frequently results in the loss or reduction of ER expression. Whether these changes are due to on-target effects of SERDs degrading ER or arise as a mechanism of tumor resistance with associated changes in cellular phenotypes remains unknown. It is critical to distinguish between these possibilities to accurately assess treatment response and determine the most appropriate subsequent therapy. To this end, we created and conducted molecular analyses on patient-derived organoid cultures from post-treatment tissue in patients receiving neoadjuvant SERD therapy for early-stage ER+ breast cancer in the I-SPY2 Endocrine Optimization Protocol (EOP). Methods: The I-SPY2 EOP study is a prospective, randomized substudy within the I-SPY TRIAL testing the oral SERD amcenestrant alone or in combination with letrozole or abemaciclib in stage 2/3 ER+ Her2-negative breast cancer. Enrollment is ongoing, with patients receiving amcenestrant neoadjuvantly for 6 months until the day before surgery. Tumor tissue is collected at baseline, 3 weeks, and at surgery. Organoids were generated from post-treatment surgical samples. Organoid cultures were optimized based on established methods (Dekkers et al., Nature Protocols, 2021) to assess ER levels and activity. Pre- and post-treatment tissue samples were also assessed for ER, PR, Ki67, and GATA3, a luminal marker and transcription factor that is functionally linked with ER, via immunohistochemistry. Results: In 7 patients with both pre- and post-treatment tissue samples including fresh surgical samples for organoid generation, the ER in baseline tumor tissue was >=90% in all patients, PR ranged from 40-90%, and Ki67 ranged from 5-30%. In post-treatment surgical tissue from these cases, ER ranged from 0-30%, PR from 0-50%, Ki67 from < 1%-10%, and GATA3 was positive in 5 of 5 cases tested to-date. The creation of organoids from residual disease at surgery was attempted for these 7 patients, with organoids successfully propagated in 5 cases thus far. 3 of 5 organoid cultures were ready for analysis and in all cases strong ER and PR expression in organoids was observed after culture for > 1 month in the absence of amcenestrant. Detailed gene expression profiling (including Mammaprint/Blueprint) and gene set enrichment analyses (GSEA) to assess for intrinsic breast cancer subtype and ER activity in each sample and corresponding organoid culture are in progress and will be reported with the full dataset. Conclusion: Patient-derived organoid culturing of residual disease after neoadjuvant endocrine therapy is feasible. Neoadjuvant treatment with a SERD can render ER and PR low or absent at the time of surgical resection, which does not necessarily imply the presence of endocrine therapy resistant disease. The use of organoids and additional IHC markers (GATA3) demonstrate that receptor negativity may be an indicator of the drug hitting its target, suggesting ER signaling is still intact. In general, patient-derived tumor organoid cultures modeling residual disease states can be a useful adjunct to existing methods used to monitor the effects of neoadjuvant endocrine therapy and is being explored in the I-SPY EOP trial. Citation Format: Jennifer Rosenbluth, Christopher J. Schwartz, Tam Binh Bui, Shruti Warhadpande, Pravin Phadatare, Sigal Eini, Michael Bruck, Julissa Molina-Vega, Kami Pullakhandam, Nicole Schindler, Lamorna A. Brown Swigart, Christina Yau, Gillian Hirst, Rita Mukhtar, Karthik V. Giridhar, Olufunmilayo I. Olopade, Kevin Kalinsky, Cheryl A. Ewing, Jasmine M. Wong, Michael D. Alvarado, Laura Van’t Veer, Laura J. Esserman, Jo Chien. Characterization of residual disease after neoadjuvant selective estrogen receptor degrader (SERD) therapy using tumor organoids in the I-SPY Endocrine Optimization Protocol (EOP) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-09-01.

Spinal stenosis is the compression of nerve roots by bone or soft tissue secondary to the narrowing of the spinal canal, lateral recesses, or intervertebral foramina. Spinal stenosis may have acquired or congenital origins. Most cases are acquired and caused by hypertrophy of the ligamentum flavum, enlarged osteophytes, degenerative arthritis, disk herniations, and various systemic illnesses. The ligamentum flavum (LF) is a highly specialized elastic ligament that connects the laminae of the spine and fuses them to the facet joint capsules. There are a number of treatment options available for spinal stenosis. Implants and surgical interventions have grown in popularity recently, and a number of these have been shown to have varying efficacy, including the minimally invasive lumbar decompression (MILD®), Vertiflex®, Coflex® Interlaminar Stabilization, and MinuteMan G3® procedures. Minimally invasive lumbar decompression (MILD®) is a minimally invasive outpatient procedure to treat spinal stenosis related to hypertrophied ligamentum flavum. The Superion® Interspinous Spacer, also known as Vertiflex®, is a titanium implant that is delivered percutaneously to relieve back pain caused by lumbar spinal stenosis. The MinuteMan® is a minimally invasive, interspinous-interlaminar fusion device planned for the temporary fixation of the thoracic, lumbar, and sacral spine, which eventually results in bony fusion. Based on our review of the available current scientific literature, the novel interventions for symptomatic lumbar spinal stenosis, such as the MILD® procedure and the Superion® interspinous spacer, generally appear to be safe and effective. There is a possibility in the future that these interventions could disrupt current treatment algorithms for lumbar spinal stenosis.

Acute and chronic pain are public health issues that clinicians have been battling for years. Opioid medications have been a treatment option for both chronic and acute pain; however, they can cause unwanted complications and are a major contributor to our present opioid epidemic. The sacroiliac (SI) joint is a common cause of both acute and chronic low back pain. It affects about 15-25% of patients with axial low back pain, and up to 40% of patients with ongoing pain following lumbar fusion. Recent advances in the treatment of SI joint pain have led to the development of a wide variety of SI joint fusion devices. These fusion devices seek to stabilize the joints themselves in order that they become immobile and, in theory, can no longer be a source for pain. This is a minimally invasive procedure aimed to address chronic pain without subjecting patients to lengthy surgery or medications, including opioids with the potential for addiction and abuse. Minimally invasive SI fusion can be performed by a lateral approach (i.e., iFuse, Tricor) or posterior approach (i.e., CornerLoc, LinQ, Rialto). The posterior approach requires the patient to be in the prone position but allows for less disruption of muscles with entry. More data are necessary to determine which fusion system may be best for a particular patient. SI fusion devices are a promising way of treating chronic lower back pain related to the SI joint. This narrative review will discuss various types of SI fusion devices, and their potential use in terms of their safety and efficacy.

Significance TRPML1 (transient receptor potential mucolipin 1) is a Ca2+-permeable, nonselective cation channel that is localized to late endosomes and lysosomes. Here, we investigated the function of TRPML1 channels in regulating lower urinary tract (LUT) smooth muscle cell (SMC) contractility. We found that TRPML1 forms a stable signaling complex with ryanodine receptors (RyRs) in the sarcoplasmic reticulum (SR). We further showed that TRPML1 channels are important for initiating an essential Ca2+-signaling negative feedback mechanism between RyRs on SR membranes and K+ channels on the plasma membrane. Knockout of TRPML1 channels in mice impaired this pathway, resulting in LUT smooth muscle hypercontractility and symptoms of overactive bladder. Our findings demonstrate a critical role for TRPML1 in LUT function., TRPML1 (transient receptor potential mucolipin 1) is a Ca2+-permeable, nonselective cation channel that is predominantly localized to the membranes of late endosomes and lysosomes (LELs). Intracellular release of Ca2+ through TRPML1 is thought to be pivotal for maintenance of intravesicular acidic pH as well as the maturation, fusion, and trafficking of LELs. Interestingly, genetic ablation of TRPML1 in mice (Mcoln1−/−) induces a hyperdistended/hypertrophic bladder phenotype. Here, we investigated this phenomenon further by exploring an unconventional role for TRPML1 channels in the regulation of Ca2+-signaling activity and contractility in bladder and urethral smooth muscle cells (SMCs). Four-dimensional (4D) lattice light-sheet live-cell imaging showed that the majority of LELs in freshly isolated bladder SMCs were essentially immobile. Superresolution microscopy revealed distinct nanoscale colocalization of LEL-expressing TRPML1 channels with ryanodine type 2 receptors (RyR2) in bladder SMCs. Spontaneous intracellular release of Ca2+ from the sarcoplasmic reticulum (SR) through RyR2 generates localized elevations of Ca2+ (“Ca2+ sparks”) that activate plasmalemmal large-conductance Ca2+-activated K+ (BK) channels, a critical negative feedback mechanism that regulates smooth muscle contractility. This mechanism was impaired in Mcoln1−/− mice, which showed diminished spontaneous Ca2+ sparks and BK channel activity in bladder and urethra SMCs. Additionally, ex vivo contractility experiments showed that loss of Ca2+ spark–BK channel signaling in Mcoln1−/− mice rendered both bladder and urethra smooth muscle hypercontractile. Voiding activity analyses revealed bladder overactivity in Mcoln1−/− mice. We conclude that TRPML1 is critically important for Ca2+ spark signaling, and thus regulation of contractility and function, in lower urinary tract SMCs.

Background: Ductal carcinoma in situ (DCIS) now represents nearly a quarter of newly diagnosed breast cancers in the United States. Standard-of-care treatment for DCIS is aggressive local therapy consisting of either mastectomy or breast conserving surgery with radiation. However, DCIS mortality is low regardless of initial treatment, suggesting opportunities to explore a spectrum of treatment options. With these treatment options, there is the potential to create risk-adapted treatment plans, but the question of how to assess risk remains. Molecular tests can help to personalize treatment by stratifying disease sub-types and providing prognosis. One such tool is the Oncotype DX® Breast DCIS Score, a risk measure which was validated in a meta-analysis of 773 patients from the E5194 and Ontario DCIS Cohort studies. Along with calculating a Breast DCIS Score™ from the expression levels of 12 genes, the test provides a predicted 10-year risk of local recurrence from the score result, age, and tumor size for patients who receive breast conserving surgery alone. Understanding how such a tool might impact decision-making will inform its implementation. Eligibility & trial design: The ATHENA Breast Health Network is a consortium of the five University of California Medical centers. Through ATHENA, patients with histologically confirmed DCIS and no concurrent invasive cancer are approached to participate in the Athena DCIS Registry. Patients in the registry facing an active management decision are eligible to participate in the Oncotype DX® DCIS prospective study. Specific aims: The primary aim of the study is to determine whether the additional diagnostic information (i.e. the DCIS Score™) impacts patient treatment decisions and physician recommendation. Additional goals are to correlate the DCIS Score™ with mammographic findings, pathological variables, and treatment recommendations, and to estimate risk within each DCIS Score™ group. Participants and their physicians answer survey questions both before and after receiving the score to evaluate the impact of the DCIS Score™ on treatment recommendations and decisions. Statistical methods: The study will assess the percentage of patients who thought the DCIS risk score influenced their treatment decision. The study will also assess whether a significant proportion of physicians changed their recommendations after considering the DCIS Score™ using the chi-square test. Similarly, the patients’ preferred treatment option pre- and post- test surveys will be evaluated. In addition, the concordance between physicians’ and patients’ choices will be assessed by the Kappa statistic before and after the score. The patients’ and physicians’ confidence levels in their treatment recommendation and decision pre- and post- test will be compared using a Wilcoxon signed-rank test, as well as the percentage of patients and physicians who are glad they used the test. In addition, the study will assess whether the DCIS test influences a patient’s perception of their recurrence risk by comparing the self-reported 10-year breast cancer recurrence risk in their pre- and post- test questionnaires using a Wilcoxon signed-rank test. Current and target accrual: The current accrual across all sites in the Oncotype study is 94 patients. The target accrual for the initial pilot phase data is defined as the first 100 patients accrued. If interested in learning more about the study, please contact Rita Mukhtar, MD (Rita.Mukhtar@ucsf.edu). Citation Format: Jane M Wei, Paul Kim, Cheryl Ewing, Jasmine Wong, Laura J Esserman, Michael D Alvarado, Abimbola O Olusanya, Skye Stewart, Ashley Tydon, Parima Daroui, Jeffrey V Kuo, Hannah L Park, Karen T Lane, Eliza Jeong, Kelsey Brown, Ava Hosseini, Barbara A Parker, Sarah L Blair, Athena Breast Health Network Investigators, Frederick Baehner, Olivier Harismendy, Antonia Petruse, Carlie K Thompson, Helena R Chang, Alexander D Borowsky, Christina Yau, Gillian L Hirst, Richard J Bold, Rita A Mukhtar. Use of Oncotype DX DCIS for disease management in a prospective DCIS registry [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-09-01.

The treatment of pain, both acute and chronic, has been a focus of medicine for generations. Physicians have tried to develop novel ways to effectively manage pain in surgical and post-surgical settings. One intervention demonstrating efficacy is nerve blocks. Single-injection peripheral nerve blocks (PNBs) are usually preferred over continuous PNBs, since they are not associated with longer lengths of stay. The challenge of single injection PNBs is their length of duration, which at present is a major limitation. Novel preparations of local anesthetics have also been studied, and these new preparations could allow for extended duration of action of anesthetics. An emerging preparation of bupivacaine, exparel, uses a multivesicular liposomal delivery system which releases medication in a steady, controlled manner. Another extended-release local anesthetic, HTX-011, consists of a combination of bupivacaine and low-dose meloxicam. Tetrodotoxin, a naturally occurring reversible site 1 sodium channel toxin derived from pufferfish and shellfish, has shown the potential to block conduction of isolated nerves. Neosaxitoxin is a more potent reversible site 1 sodium channel toxin also found in shellfish that can also block nerve conduction. These novel formulations show great promise in terms of the ability to prolong the duration of single injection PNBs. This field is still currently in development, and more researchers will need to be done to ensure the efficacy and safety of these novel formulations. These formulations could be the future of pain management if ongoing research continues to prove positive effects and low side effect profiles.

El trabajo “Un software para la educación medioambiental en el área de Estudios Sociales”, reflexiona históricamente acerca de la problemática medio ambiental. Ante la interrogante de cómo educar al hombre para detener y revertir la crisis medio ambiental a que hoy se asiste, o cómo educar en cuanto se refiere al cuidado y conservación del medio ambiente, los autores proponen laborar por una educación ambiental que tenga como objetivo apropiar al estudiante del conocimiento de la problemática. Como resultado se han de favorecer modos de actuación tendentes a la solución de la misma. Para ello, se propone el empleo de un software educativo, aplicado en la asignatura Estudios Sociales, en el octavo grado de una escuela. La aplicación interactiva contará con actividades motivadoras y reflexivas, dirigidas a motivar el cuidado del medioambiente, a partir de dicha materia.

Peripheral coupling between the sarcoplasmic reticulum (SR) and plasma membrane (PM) forms signaling complexes that regulate the membrane potential and contractility of vascular smooth muscle cells (VSMCs). The mechanisms responsible for these membrane interactions are poorly understood. In many cells, STIM1 (stromal interaction molecule 1), a single-transmembrane-domain protein that resides in the endoplasmic reticulum (ER), transiently moves to ER-PM junctions in response to depletion of ER Ca2+ stores and initiates store-operated Ca2+ entry (SOCE). Fully differentiated VSMCs express STIM1 but exhibit only marginal SOCE activity. We hypothesized that STIM1 is constitutively active in contractile VSMCs and maintains peripheral coupling. In support of this concept, we found that the number and size of SR-PM interacting sites were decreased, and SR-dependent Ca2+-signaling processes were disrupted in freshly isolated cerebral artery SMCs from tamoxifen-inducible, SMC-specific STIM1-knockout (Stim1-smKO) mice. VSMCs from Stim1-smKO mice also exhibited a reduction in nanoscale colocalization between Ca2+-release sites on the SR and Ca2+-activated ion channels on the PM, accompanied by diminished channel activity. Stim1-smKO mice were hypotensive, and resistance arteries isolated from them displayed blunted contractility. These data suggest that STIM1 – independent of SR Ca2+ store depletion – is critically important for stable peripheral coupling in contractile VSMCs.

Spinal stenosis is the compression of nerve roots by bone or soft tissue secondary to the narrowing of the spinal canal, lateral recesses, or intervertebral foramina. Spinal stenosis may have acquired or congenital origins. Most cases are acquired and caused by hypertrophy of the ligamentum flavum, enlarged osteophytes, degenerative arthritis, disk herniations, and various systemic illnesses. The ligamentum flavum (LF) is a highly specialized elastic ligament that connects the laminae of the spine and fuses them to the facet joint capsules. There are a number of treatment options available for spinal stenosis. Implants and surgical interventions have grown in popularity recently, and a number of these have been shown to have varying efficacy, including the minimally invasive lumbar decompression (MILD

TRPA1 (transient receptor potential ankyrin 1), the lone member of the mammalian ankyrin TRP subfamily, is a Ca2+-permeable, non-selective cation channel. TRPA1 channels are localized to the plasma membranes of various cells types, including sensory neurons and vascular endothelial cells. The channel is endogenously activated by byproducts of reactive oxygen species, such as 4-hydroxy-2-noneal, as well as aromatic, dietary molecules including allyl isothiocyanate, a derivative of mustard oil. Several studies have implicated TRPA1 as a regulator of vascular tone that acts through distinct mechanisms. First, TRPA1 on adventitial sensory nerve fibers mediates neurogenic vasodilation by stimulating the release of the vasodilator, calcitonin gene-related peptide. Second, TRPA1 is expressed in the endothelium of the cerebral vasculature, but not in other vascular beds, and its activation results in localized Ca2+ signals that drive endothelium-dependent vasodilation. Finally, TRPA1 is functionally present on brain capillary endothelial cells, where its activation orchestrates a unique biphasic propagation mechanism that dilates upstream arterioles. This response is vital for neurovascular coupling and functional hyperemia in the brain. This review provides a brief overview of the biophysical and pharmacological properties of TRPA1 and discusses the importance of the channel in vascular control and pathophysiology.

Blood flow regulation in the brain is dynamically regulated to meet the metabolic demands of active neuronal populations. Recent evidence has demonstrated that capillary endothelial cells are essential mediators of neurovascular coupling that sense neuronal activity and generate a retrograde, propagating, hyperpolarizing signal that dilates upstream arterioles. Here, we tested the hypothesis that transient receptor potential ankyrin 1 (TRPA1) channels in capillary endothelial cells are significant contributors to functional hyperemic responses that underlie neurovascular coupling in the brain. Using an integrative ex vivo and in vivo approach, we demonstrate the functional presence of TRPA1 channels in brain capillary endothelial cells, and show that activation of these channels within the capillary bed, including the post-arteriole transitional region covered by ensheathing mural cells, initiates a retrograde signal that dilates upstream parenchymal arterioles. Notably, this signaling exhibits a unique biphasic mode of propagation that begins within the capillary network as a short-range, Ca2+ signal dependent on endothelial pannexin-1 channel/purinergic P2X receptor communication pathway and then is converted to a rapid, inward-rectifying K+ channel-mediated electrical signal in the post-arteriole transitional region that propagates upstream to parenchymal arterioles. Two-photon laser-scanning microscopy further demonstrated that conductive vasodilation occurs in vivo, and that TRPA1 is necessary for functional hyperemia within the somatosensory cortex of mice. Together, these data establish a role for endothelial TRPA1 channels as sensors of neuronal activity and show that they respond accordingly by initiating a vasodilatory response that redirects blood to regions of metabolic demand.

Cerebral blood flow is dynamically regulated by neurovascular coupling to meet the dynamic metabolic demands of the brain. We hypothesized that TRPA1 channels in capillary endothelial cells are stimulated by neuronal activity and instigate a propagating retrograde signal that dilates upstream parenchymal arterioles to initiate functional hyperemia. We find that activation of TRPA1 in capillary beds and post-arteriole transitional segments with mural cell coverage initiates retrograde signals that dilate upstream arterioles. These signals exhibit a unique mode of biphasic propagation. Slow, short-range intercellular Ca2+ signals in the capillary network are converted to rapid electrical signals in transitional segments that propagate to and dilate upstream arterioles. We further demonstrate that TRPA1 is necessary for functional hyperemia and neurovascular coupling within the somatosensory cortex of mice in vivo. These data establish endothelial cell TRPA1 channels as neuronal activity sensors that initiate microvascular vasodilatory responses to redirect blood to regions of metabolic demand.

Advances in the surgical management of the axilla in patients treated with neoadjuvant chemotherapy, especially those with node positive disease at diagnosis, have led to changes in practice and more judicious use of axillary lymph node dissection that may minimize morbidity from surgery. However, there is still significant confusion about how to optimally manage the axilla, resulting in variation among practices. From the viewpoint of drug development, assessment of response to neoadjuvant chemotherapy remains paramount and appropriate assessment of residual disease—the primary endpoint of many drug therapy trials in the neoadjuvant setting—is critical. Therefore decreasing the variability, especially in a multicenter clinical trial setting, and establishing a minimum standard to ensure consistency in clinical trial data, without mandating axillary lymph node dissection, for all patients is necessary. The key elements which include proper staging and identification of nodal involvement at diagnosis, and appropriately targeted management of the axilla at the time of surgical resection are presented. The following protocols have been adopted as standard procedure by the I-SPY2 trial for management of axilla in patients with node positive disease, and present a framework for prospective clinical trials and practice.

The RET receptor tyrosine kinase is crucial for the development of the enteric nervous system (ENS), acting as a receptor for Glial cell line-derived neurotrophic factor (GDNF) via GFR co-receptors. Drosophila has a well-conserved RET homolog (Ret) that has been proposed to function independently of the Gfr-like co-receptor (Gfrl). We find that Ret is required for development of the stomatogastric (enteric) nervous system in both embryos and larvae, and its loss results in feeding defects. Live imaging analysis suggests that peristaltic waves are initiated but not propagated in mutant midguts. Examination of axons innervating the midgut reveals increased branching but the area covered by the branches is decreased. This phenotype can be rescued by Ret expression. Additionally, Gfrl shares the same ENS and feeding defects, suggesting that Ret and Gfrl might function together via a common ligand. We identified the TGFβ family member Maverick (Mav) as a ligand for Gfrl and a Mav chromosomal deficiency displayed similar embryonic ENS defects. Our results suggest that the Ret and Gfrl families co-evolved before the separation of invertebrate and vertebrate lineages.

The RET receptor tyrosine kinase is critical for the development of the enteric nervous system (ENS), acting as a receptor for Glial Cell Line-Derived Neurotrophic Factor (GDNF) via GFR co-receptors. Drosophila has a well-conserved RET homologue (Ret) that has been proposed to function independently of the Gfr-like co-receptor (Gfrl). We find that Ret is required for development of the stomatogastric (enteric) nervous system (SNS) in both embryos and larvae, and its loss results in feeding defects. Live imaging analysis suggests that peristaltic waves are initiated but not propagated in mutant midguts. Examination of axons innervating the midgut reveals increased branching but the area covered by the branches is decreased. This phenotype can be rescued by Ret expression. Additionally, Gfrl shares the same ENS and feeding defects, suggesting that Ret and Gfrl might function together to respond to a ligand. We identified the TGFβ family member Maverick (Mav) as a ligand for Gfrl and a Mav chromosomal deficiency displayed similar embryonic ENS defects. Our results suggest that the Ret and Gfrl families co-evolved before the separation of invertebrate and vertebrate lineages.