Bamimore, Michael

Abstract INTRODUCTION Lung cancer is the most common tumor to metastasize to the brain, as 40% of patients develop brain metastasis (BM). Once diagnosed, survival is only 6.5-10 months. A potential target to prevent BM is circulating tumor cells (CTCs). The mechanisms that mediate a CTCs adaptation to the harsh environment of circulation and BM have not been elucidated. We have demonstrated that primary lung cancer cells (LCCs) subjected to circulation have increased migration across brain endothelial cell monolayers, increased side population, and decrease survival in rodents when injected intracardially vs plated controls. METHODS We engineered a microfluidic device capable of subjecting tumor cells to prolonged circulatory shear stress (CSS) that allows the isolation/modeling of CTC-like cells. Primary LCCs (A549, H1563) were subjected to circulation, suspension, or plated (2D) for 72h as controls. At this time point, LCCs were collected, and total mRNA was extracted. Samples were submitted for RNA sequencing. Weighted gene co-expression network analysis (WCGNA) and Ingenuity Pathway Analysis were performed. (FC >2 and p-value <0.05). RESULTS Transcriptomic analysis indicates that cells subjected to CSS activate specific gene networks involved in cell survival, migration, invasion, adhesion of tumor cells, and cytoskeletal reorganization (z-score: >2, p-value: 0.05). Canonical pathways in CTCs included ILK-signaling and Xenobiotic Metabolism. LCCs exposed to CSS had increased expression of multidrug resistance pumps ABCC2, ABCF2 (P:<0.001), and side population on flow cytometry (P: <0.05). The top differentially expressed genes in CTC-like cells (MMP1, ANGPTL4, and CEMIP) were involved in the invasion, angiogenesis, and pre-metastatic niche (PMN) formation of BM. CONCLUSION LCCs that survive CSS have increased expression of genes associated with migration, invasion, and chemoresistance compared to 2D controls. Targeting genes in CTCs that mediate survival and preparation of the PMN may be useful in preventing BM.

Introduction Poor‐grade aneurysmal subarachnoid hemorrhage (aSAH) is associated with high mortality. Overall, 20–30% of aSAH are described as poor grade. Despite recent advances in management strategies, prognosis of poor‐grade aSAH remains dismal. As such, we review the most current literature regarding management strategies that can be used to decrease the risk of the four most common causes of secondary brain injury: 1) aneurysm re‐rupture, 2) hydrocephalus, 3) cerebral salt wasting, and 4) delayed cerebral ischemia/vasospasm. Methods We present a 46‐year‐old female patient with poor‐grade aSAH after a loss of consciousness following thunderclap headache. Examination showed a dilated left pupil and Glasgow Coma Scale (GCS) of 4. Imaging revealed a ruptured anterior communicating artery aneurysm, and she was subsequently taken to the neuro‐interventional radiology suite for EVD placement. On POD 7 Transcranial Doppler (TCD) suggested moderate vasospam of left MCA. Two successful balloon angioplasties of the basilar, ACA‐A1, and MCA‐M1 were successfully performed on separate consecutive days. By POD 10, intermittent severe ICP spikes required targeted temperature management (TTM) with hypothermia. On POD 24, her ICP normalized, she was no longer comatose, and her EVD was clamped and removed. She was rapidly weaned off ventilator and transitioned to rehabilitation. 3‐months postoperatively, Modified Rankin Scale score was 0. Results Based upon the result of our literature review, we propose maintaining blood pressure below 160 mmHg prior to intervention, after which it can be increased to 160–240 mmHg to prevent vasospasm. Transcranial Doppler is essential to detect vasospasm as the aSAH symptoms subtle; once identified, vasospasm can be successfully treated with balloon angioplasty. Finally, targeted temperature management, mannitol, hypertonic saline, and neuromuscular paralysis are essential for postoperative management of ICP levels. Conclusions The multimodal approach should be considered when managing poor grade aSAH. Further research in aSAH management would benefit the patients who present with poor prognosis, thereby improving patient care and leading to a standard, effective approach for aSAH management.

Leptomeningeal carcinomatosis (LMC) is a fatal but uncommon complication occurring in 5–15% of patients with stage IV cancer. Current treatment options are ineffective at managing leptomeningeal spread, with a median overall survival (mOS) of 2–6 months. We aimed to conduct a systematic review of the literature to identify past and future therapies for LMC from solid tumors. Forty-three clinical trials (CTs) published between 1982–2022 were identified. Of these, 35 (81.4%) were non-randomized CTs and 8 (18.6%) were randomized CTs. The majority consisted of phase I (16.3%) and phase II CTs (65.1%). Trials enrolled patients with LMC from various primary histology (n = 23, 57.5%), with one CT evaluating LCM from melanoma (2.4%). A total of 21 trials evaluated a single modality treatment. Among CTs, 23.7% closed due to low accrual. Intraventricular (ITV)/intrathecal (IT) drug delivery was the most common route of administration (n = 22, 51.2%) vs. systemic drug delivery (n = 13, 30.3%). Two clinical trials evaluated the use of craniospinal irradiation for LMC with favorable results. LMC continues to carry a dismal prognosis, and over the years, increments in survival have remained stagnant. A paradigm shift towards targeted systemic therapy with continued standardization of efficacy endpoints will help to shed light on promising treatments.