High-dose chemotherapy and peripheral blood stem cell transplantation as salvage therapy in primary mediastinal nonseminomatous germ cell tumors: The Indiana University experience.

BACKGROUND: Patients with relapsed primary mediastinal nonseminomatous germ cell tumor have low cure rates with salvage chemotherapy or surgery. The authors report survival outcomes of patients who received high-dose chemotherapy (HDCT) and peripheral blood stem cell transplantation (PBSCT) at Indiana University. METHODS: The prospectively maintained Indiana University germ cell tumor database identified 32 patients with primary mediastinal nonseminomatous germ cell tumor who progressed after first-line cisplatin-based combination chemotherapy and received HDCT and PBSCT between 2006 and 2021. Therapy included two consecutive courses of HDCT consisting of 700 mg/m2 carboplatin and 750 mg/m2 etoposide, each for 3 consecutive days, and each followed by PBSCT. A second course was not given if the patient experienced progressive disease or prohibitive toxicity. Progression-free survival and overall survival were analyzed using the Kaplan-Meier method. Medians with 95% confidence intervals were also calculated along with 2-year probabilities. RESULTS: The median age at HDCT was 30 years (range, 18-61 years). With a median follow-up of 4.7 years (range, 1-14 years), the 2-year progression-free survival rate was 31% (95% confidence interval, 16%-47%), and the 2-year overall survival rate was 35% (95% confidence interval, 19%-52%). At last follow-up, nine patients (28%) remained without evidence of disease, including two platinum-refractory patients and two patients who were receiving HDCT as third-line therapy. There were three treatment-related deaths. CONCLUSIONS: Salvage HDCT and PBSCT is an active combination in patients who have relapsed primary mediastinal nonseminomatous germ cell tumor with curative potential and prolonged survival, including in platinum-refractory and third-line settings. The authors recommend this approach for initial salvage chemotherapy in this patient population.

Adenocarcinoma Harboring EGFR-RAD51 Fusion Treated With Osimertinib: A Case Report.

EGFR mutations are among the most common driver mutations in lung adenocarcinoma. Rare alterations, such as the EGFR-RAD51 fusion, respond to treatment with EGFR tyrosine kinase inhibitors but can be missed by limited genomic sequencing panels. Here, we report a case of metastatic lung adenocarcinoma in a never-smoker patient who initially did not have a targetable alteration identified on two different sequencing panels. The initial response to combination chemoimmunotherapy was short-lived. A rare EGFR-RAD51 fusion was then identified using a more in-depth sequencing panel. The patient experienced a dramatic and durable response to osimertinib. This case highlights the rarity of EGFR-RAD51 fusions, the efficacy of EGFR tyrosine kinase inhibitors, and the importance of a thorough search for targetable alterations in never-smokers with lung adenocarcinoma.

Late Relapse of Germ Cell Tumors After Prior Chemotherapy or Surgery-only.

BACKGROUND: Late relapse (LR) of germ cell tumor (GCT) is defined as relapsed disease >2 years from initial treatment. LR remains a challenge both for optimal screening methods and management. We report the method of detection, treatments received, and outcomes in patients with chemotherapy-exposed vs chemotherapy-naïve LR GCT. PATIENTS AND METHODS: The Indiana University testicular cancer database was queried identifying 131 patients with LR GCT evaluated at Indiana University from January 2000 to January 2019. Method of detection of LR was recorded along with site, treatment received, and survival outcomes. The cohort was divided into 4 groups according to seminoma versus non-seminoma GCT (NSGCT) and chemotherapy-exposed vs chemotherapy-naïve LR. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and compared using the log-rank test. Medians with 95% confidence intervals were also calculated along with the 2-year probabilities. RESULTS: Median age at LR was 38.3 (range, 19.3-56.8). Chemotherapy-exposed accounted for 75 (57%) and chemotherapy-naïve for 56 (43%) of cases. The 2-year OS comparing chemotherapy-exposed versus chemotherapy-naïve was 78.2% versus 100% (P = .0003). For the 72 chemo-exposed NSGCT LR pts, 2-year PFS based on treatment: surgery vs chemotherapy versus surgery + chemotherapy was 67.1% versus 0% versus 47.1% (P < 0.0001). Fifty-nine percent of chemotherapy-exposed LR had elevation of alpha fetoprotein (AFP) at LR diagnosis. CONCLUSION: GCT pts require lifetime follow-up with annual physical exam and tumor markers. Surgical resection, when feasible, remains the preferred treatment for chemotherapy-exposed LR. Chemotherapy-exposed LR has worse outcomes compared to chemotherapy-naïve LR patients.

Tuning the performance of CAR T cell immunotherapies.

BACKGROUND: Simultaneous advances in gene editing, T cell engineering and biotechnology currently provide an opportunity for rapid progress in medicine. The approval of chimeric antigen receptor (CAR) T cell therapies by the US Food and Drug Administration (FDA) and the European Commission have generated substantial momentum for these first-in-class therapies to be used in patients with B cell malignancies. MAIN BODY: Considerable efforts focus on improved outcomes and reduced side effects of the newly approved therapies. Using innovative strategies, researchers aim to extend CAR T cell use to tackle difficulties inherent in solid tumors. Efforts are underway to broaden the applications of CAR T cells, and the strategy has been successful in chronic viral infections and preclinical models of autoimmunity. Research is in progress to generate "off-the-shelf" CAR T cells, an advance, which would greatly increase patient availability and reduce treatment cost. CONCLUSIONS: In this thematic review, we highlight advances that may help develop genetically engineered cells into a new category of medical therapies.

Prostate-specific membrane antigen (PSMA)-mediated laminin proteolysis generates a pro-angiogenic peptide.

Prostate-specific membrane antigen (PSMA) is a membrane-bound glutamate carboxypeptidase expressed in a number of tissues. PSMA participates in various biological functions depending on the substrate available in the particular tissue; in the brain, PSMA cleaves the abundant neuropeptide N-acetyl-aspartyl-glutamate to regulate release of key neurotransmitters, while intestinal PSMA cleaves polyglutamated peptides to supply dietary folate. PSMA expression is also progressively upregulated in prostate cancer where it correlates with tumor progression as well as in tumor vasculature, where it regulates angiogenesis. The previous research determined that PSMA cleavage of small peptides generated via matrix metalloprotease-mediated proteolysis of the extracellular matrix protein laminin potently activated endothelial cells, integrin signaling and angiogenesis, although the specific peptide substrates were not identified. Herein, using enzymatic analyses and LC/MS, we unequivocally demonstrate that several laminin-derived peptides containing carboxy-terminal glutamate moieties (LQE, IEE, LNE) are bona fide substrates for PSMA. Subsequently, the peptide products were tested for their effects on angiogenesis in various models. We report that LQ, the dipeptide product of PSMA cleavage of LQE, efficiently activates endothelial cells in vitro and enhances angiogenesis in vivo. Importantly, LQE is not cleaved by an inactive PSMA enzyme containing an active site mutation (E424S). Endothelial cell activation by LQ was dependent on integrin beta-1-induced activation of focal adhesion kinase. These results characterize a novel PSMA substrate, provide a functional rationale for the upregulation of PSMA in cancer cells and tumor vasculature and suggest that inhibition of PSMA could lead to the development of new angiogenic therapies.