One step 4× and 12× 3D-ExM enables robust super-resolution microscopy of nanoscale cellular structures.

Super-resolution microscopy has become an indispensable tool across diverse research fields, offering unprecedented insights into biological architectures with nanometer scale resolution. Compared with traditional nanometer-scale imaging methods such as electron microscopy, super-resolution microscopy offers several advantages, including the simultaneous labeling of multiple target biomolecules with high specificity and simpler sample preparation, making it accessible to most researchers. In this study, we introduce two optimized methods of super-resolution imaging: 4-fold and 12-fold 3D-isotropic and preserved Expansion Microscopy (4× and 12× 3D-ExM).

One step 4x and 12x 3D-ExM: robust super-resolution microscopy in cell biology.

Super-resolution microscopy has become an indispensable tool across diverse research fields, offering unprecedented insights into biological architectures with nanometer scale resolution. Compared to traditional nanometer-scale imaging methods such as electron microscopy, super-resolution microscopy offers several advantages, including the simultaneous labeling of multiple target biomolecules with high specificity and simpler sample preparation, making it accessible to most researchers. In this study, we introduce two optimized methods of super-resolution imaging: 4-fold and 12-fold 3D-isotropic and preserved Expansion Microscopy (4x and 12x 3D-ExM).

CENP-E Inhibition Induces Chromosomal Instability and Synergizes with Diverse Microtubule-Targeting Agents in Breast Cancer.

Drugs that perturb microtubules are commonly used to treat breast cancers of all subtypes in both early stage and metastatic disease, but they are effective in only approximately 50% of patients. High concentrations of microtubule-targeting agents can elicit mitotic arrest in cell culture models; however, recent evidence from primary and metastatic breast cancers has revealed that these agents only accumulate at intratumoral levels capable of inducing abnormal multipolar mitotic spindles, not mitotic arrest. Although the maintenance of multipolar spindles can generate cytotoxic rates of chromosomal instability (CIN), focusing of aberrant multipolar spindles into normal bipolar spindles can dramatically reduce CIN and confer resistance to microtubule poisons.

Genetic Testing Utilization: Discrepancies Between Somatic and Germline Results in Patients With Cancer Reviewed at the UW Health Precision Medicine Molecular Tumor Board.

Purpose: Somatic and germline testing are increasingly used to estimate risks for patients with cancer. Although both germline testing and somatic testing can identify genetic variants that could change a patient's care and eligible treatments, the aims of these tests and their technologies are fundamentally different and cannot be used interchangeably. This study examines the timing and results of somatic and germline genetic testing for patients with cancer at UW Health.

A survey of chromosomal instability measures across mechanistic models.

Chromosomal instability (CIN) is the persistent reshuffling of cancer karyotypes via chromosome mis-segregation during cell division. In cancer, CIN exists at varying levels that have differential effects on tumor progression. However, mis-segregation rates remain challenging to assess in human cancer despite an array of available measures.

The Right Dose: Results of a Patient Advocate-Led Survey of Individuals With Metastatic Breast Cancer Regarding Treatment-Related Side Effects and Views About Dosage Assessment to Optimize Quality of Life.

Purpose: Although patients with metastatic breast cancer (MBC) have been living longer with the advent of more effective treatments such as targeted therapy and immunotherapy, the disease remains incurable, and most patients will undergo therapy indefinitely. When beginning therapy, patients are typically prescribed dose often based upon the maximum tolerated dose identified in phase I clinical trials. However, patients' perspectives about tolerability and willingness to discuss individualized dosing of drugs upon initiation of a new regimen and throughout the course of treatment have not been comprehensively evaluated.

The reckoning of chromosomal instability: past, present, future.

Quantitative measures of CIN are crucial to our understanding of its role in cancer. Technological advances have changed the way CIN is quantified, offering increased accuracy and insight. Here, we review measures of CIN through its rise as a field, discuss considerations for its measurement, and look forward to future quantification of CIN.

Diverse microtubule-targeted anticancer agents kill cells by inducing chromosome missegregation on multipolar spindles.

Microtubule-targeted agents are commonly used for cancer treatment, though many patients do not benefit. Microtubule-targeted drugs were assumed to elicit anticancer activity via mitotic arrest because they cause cell death following mitotic arrest in cell culture. However, we recently demonstrated that intratumoral paclitaxel concentrations are insufficient to induce mitotic arrest and rather induce chromosomal instability (CIN) via multipolar mitotic spindles.

Association of Neighborhood Disadvantage with Short- and Long-Term Outcomes After Pancreatectomy for Pancreatic Ductal Adenocarcinoma.

Background: While lower socioeconomic status has been shown to correlate with worse outcomes in cancer care, data correlating neighborhood-level metrics with outcomes are scarce. We aim to explore the association between neighborhood disadvantage and both short- and long-term postoperative outcomes in patients undergoing pancreatectomy for pancreatic ductal adenocarcinoma (PDAC).

Patients And Methods: We retrospectively analyzed 243 patients who underwent resection for PDAC at a single institution between 1 January 2010 and 15 September 2021.

Validation of Immunotherapy Response Score as Predictive of Pan-solid Tumor Anti-PD-1/PD-L1 Benefit.

Unlabelled: Immunotherapy response score (IRS) integrates tumor mutation burden (TMB) and quantitative expression biomarkers to predict anti-PD-1/PD-L1 [PD-(L)1] monotherapy benefit. Here, we evaluated IRS in additional cohorts. Patients from an observational trial (NCT03061305) treated with anti-PD-(L)1 monotherapy were included and assigned to IRS-High (-H) versus -Low (-L) groups.

A survey of CIN measures across mechanistic models.

Chromosomal instability (CIN) is the persistent reshuffling of cancer karyotypes via chromosome mis-segregation during cell division. In cancer, CIN exists at varying levels that have differential effects on tumor progression. However, mis-segregation rates remain challenging to assess in human cancer despite an array of available measures.

Accuracy of models to prognosticate survival after surgery for pancreatic cancer in the era of neoadjuvant therapy.

Background: Outcomes for pancreatic adenocarcinoma (PDAC) remain difficult to prognosticate. Multiple models attempt to predict survival following the resection of PDAC, but their utility in the neoadjuvant population is unknown. We aimed to assess their accuracy among patients that received neoadjuvant chemotherapy (NAC).

Misaligned Chromosomes are a Major Source of Chromosomal Instability in Breast Cancer.

Unlabelled: Chromosomal instability (CIN), the persistent reshuffling of chromosomes during mitosis, is a hallmark of human cancers that contributes to tumor heterogeneity and has been implicated in driving metastasis and altering responses to therapy. Though multiple mechanisms can produce CIN, lagging chromosomes generated from abnormal merotelic attachments are the major cause of CIN in a variety of cell lines, and are expected to predominate in cancer. Here, we quantify CIN in breast cancer using a tumor microarray, matched primary and metastatic samples, and patient-derived organoids from primary breast cancer.

Development and validation of an integrative pan-solid tumor predictor of PD-1/PD-L1 blockade benefit.

Background: Anti-PD-1 and PD-L1 (collectively PD-[L]1) therapies are approved for many advanced solid tumors. Biomarkers beyond PD-L1 immunohistochemistry, microsatellite instability, and tumor mutation burden (TMB) may improve benefit prediction.

Methods: Using treatment data and genomic and transcriptomic tumor tissue profiling from an observational trial (NCT03061305), we developed Immunotherapy Response Score (IRS), a pan-tumor predictive model of PD-(L)1 benefit.

Increased Aurora B expression reduces substrate phosphorylation and induces chromosomal instability.

Increased Aurora B protein expression, which is common in cancers, is expected to increase Aurora B kinase activity, yielding elevated phosphorylation of Aurora B substrates. In contrast, here we show that elevated expression of Aurora B reduces phosphorylation of six different Aurora B substrates across three species and causes defects consistent with Aurora B inhibition. Complexes of Aurora B and its binding partner INCENP autophosphorylate in trans to achieve full Aurora B activation.

Patient-centered dosing: oncologists' perspectives about treatment-related side effects and individualized dosing for patients with metastatic breast cancer (MBC).

Purpose: Although metastatic breast cancer (MBC) is treatable, it is not curable and most patients remain on treatment indefinitely. While oncologists commonly prescribe the recommended starting dose (RSD) from the FDA-approved label, patient tolerance may differ from that seen in clinical trials. We report on a survey of medical oncologists' perspectives about treatment-related toxicity and willingness to discuss flexible dosing with patients.

Quantifying chromosomal instability from intratumoral karyotype diversity using agent-based modeling and Bayesian inference.

Chromosomal instability (CIN)-persistent chromosome gain or loss through abnormal mitotic segregation-is a hallmark of cancer that drives aneuploidy. Intrinsic chromosome mis-segregation rate, a measure of CIN, can inform prognosis and is a promising biomarker for response to anti-microtubule agents. However, existing methodologies to measure this rate are labor intensive, indirect, and confounded by selection against aneuploid cells, which reduces observable diversity.

Clinical utility of a regional precision medicine molecular tumor board and challenges to implementation.

Purpose: Molecular tumor boards provide precision treatment recommendations based on cancer genomic profile. However, practical barriers limit their benefits. We studied the clinical utility of the precision medicine molecular tumor board (PMMTB) and described challenges with PMMTB implementation.

Breast cancer immunotherapy: current biomarkers and the potential of assays.

Breakthroughs in metastatic breast cancer care require new model systems that can identify the unique features and vulnerabilities of each cancer. Primary tumor cultures are proposed to efficiently screen multiple treatment options in a patient-specific strategy to maximize therapeutic benefit, minimize toxicity, and enable mechanistic insights that inspire future biomarkers for patient selection. To realize the potential of patient-specific cultures, new tools are needed to capture cell-by-cell variability in behavior and dynamic response to treatments in living 3D specimens.

Classes of therapeutics to amplify the immune response.

Purpose: Conventional chemotherapies are a mainstay for metastatic breast cancers, though durable response is rare. Immunotherapies promise long-term responses thorough immune activation but have been underwhelming in breast cancer relative to other cancer types. Here, we review the mechanisms of existing strategies including chemotherapies and how they may cause breast cancers to become immunogenic to identify potential biomarkers for combinations of conventional and immunotherapies.

Chromosomal instability sensitizes patient breast tumors to multipolar divisions induced by paclitaxel.

Paclitaxel (Taxol) is a cornerstone of cancer treatment. However, its mechanism of cytotoxicity is incompletely understood and not all patients benefit from treatment. We show that patients with breast cancer did not accumulate sufficient intratumoral paclitaxel to induce mitotic arrest in tumor cells.

Real-World Performance of a Comprehensive Genomic Profiling Test Optimized for Small Tumor Samples.

Purpose: Tissue-based comprehensive genomic profiling (CGP) is increasingly used for treatment selection in patients with advanced cancer; however, tissue availability may limit widespread implementation. Here, we established real-world CGP tissue availability and assessed CGP performance on consecutively received samples.

Materials And Methods: We conducted a post hoc, nonprespecified analysis of 32,048 consecutive tumor tissue samples received for StrataNGS, a multiplex polymerase chain reaction (PCR)-based comprehensive genomic profiling (PCR-CGP) test, as part of an ongoing observational trial (NCT03061305).

E2112: Randomized Phase III Trial of Endocrine Therapy Plus Entinostat or Placebo in Hormone Receptor-Positive Advanced Breast Cancer. A Trial of the ECOG-ACRIN Cancer Research Group.

Purpose: Endocrine therapy resistance in advanced breast cancer remains a significant clinical problem that may be overcome with the use of histone deacetylase inhibitors such as entinostat. The ENCORE301 phase II study reported improvement in progression-free survival (PFS) and overall survival (OS) with the addition of entinostat to the steroidal aromatase inhibitor (AI) exemestane in advanced hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

Patients And Methods: E2112 is a multicenter, randomized, double-blind, placebo-controlled phase III study that enrolled men or women with advanced HR-positive, HER2-negative breast cancer whose disease progressed after nonsteroidal AI.